Fix ringbuffer tests for newline

The use of "final" differed between ansicolor_sink and wincolor_sink,
resulting in the code inheriting from std{err,out}_color_sink classes,
which are defined as one or the other on different platforms, being able
to override most of the functions under non-Windows platforms, but not
under Windows.

This seems gratuitously inconsistent, so just remove all "final"
keywords from both classes, especially because there doesn't seem any
good reason to use it and the other sink classes don't use it (with the
exception of base_sink, which is special).

This also incidentally fixes using "final override" in most places but
"override final" in wincolor_sink.h.

Fixes #3429.

.clang-format

@@ -1,108 +1,19 @@
 ---
 Language:        Cpp
-# BasedOnStyle:  LLVM
+BasedOnStyle:  Google
 AccessModifierOffset: -4
-AlignAfterOpenBracket: DontAlign
-AlignConsecutiveAssignments: false
-AlignConsecutiveDeclarations: false
-AlignEscapedNewlines: Right
-AlignOperands:   true
-AlignTrailingComments: true
-AllowAllParametersOfDeclarationOnNextLine: true
-AllowShortBlocksOnASingleLine: true
-AllowShortCaseLabelsOnASingleLine: false
-AllowShortFunctionsOnASingleLine: Empty
-AllowShortIfStatementsOnASingleLine: false
-AllowShortLoopsOnASingleLine: false
-AlwaysBreakAfterDefinitionReturnType: None
-AlwaysBreakAfterReturnType: None
-AlwaysBreakBeforeMultilineStrings: false
-AlwaysBreakTemplateDeclarations: true
-BinPackArguments: true
-BinPackParameters: true
-BraceWrapping:     
-  AfterClass:      true
-  AfterControlStatement: true
-  AfterEnum:       true
-  AfterFunction:   true
-  AfterNamespace:  false
-  AfterObjCDeclaration: true
-  AfterStruct:     true
-  AfterUnion:      true
-  BeforeCatch:     true
-  BeforeElse:      true
-  IndentBraces:    false
-  SplitEmptyFunction: false
-  SplitEmptyRecord: false
-  SplitEmptyNamespace: false
-BreakBeforeBinaryOperators: None
-BreakBeforeBraces: Custom
-BreakBeforeInheritanceComma: false
-BreakBeforeTernaryOperators: true
-BreakConstructorInitializersBeforeComma: true
-BreakConstructorInitializers: BeforeColon
-BreakAfterJavaFieldAnnotations: false
-BreakStringLiterals: true
-ColumnLimit:     140
-CommentPragmas:  '^ IWYU pragma:'
-CompactNamespaces:  false
-ConstructorInitializerAllOnOneLineOrOnePerLine: false
-ConstructorInitializerIndentWidth: 4
-ContinuationIndentWidth: 4
-Cpp11BracedListStyle: true
-DerivePointerAlignment: false
-DisableFormat:   false
-ExperimentalAutoDetectBinPacking: false
-FixNamespaceComments: true
-ForEachMacros:   
-  - foreach
-  - Q_FOREACH
-  - BOOST_FOREACH
-IncludeCategories: 
-  - Regex:           '^"(llvm|llvm-c|clang|clang-c)/'
-    Priority:        2
-  - Regex:           '^(<|"(gtest|gmock|isl|json)/)'
-    Priority:        3
-  - Regex:           '.*'
-    Priority:        1
-IncludeIsMainRegex: '(Test)?$'
-IndentCaseLabels: false
+Standard:        c++17
 IndentWidth:     4
-IndentWrappedFunctionNames: false
-JavaScriptQuotes: Leave
-JavaScriptWrapImports: true
-KeepEmptyLinesAtTheStartOfBlocks: true
-MacroBlockBegin: ''
-MacroBlockEnd:   ''
-MaxEmptyLinesToKeep: 1
-NamespaceIndentation: None
-ObjCBlockIndentWidth: 2
-ObjCSpaceAfterProperty: false
-ObjCSpaceBeforeProtocolList: true
-PenaltyBreakAssignment: 2
-PenaltyBreakBeforeFirstCallParameter: 19
-PenaltyBreakComment: 300
-PenaltyBreakFirstLessLess: 120
-PenaltyBreakString: 1000
-PenaltyExcessCharacter: 1000000
-PenaltyReturnTypeOnItsOwnLine: 60
-PointerAlignment: Right
-ReflowComments:  true
-SortIncludes:    false
-SortUsingDeclarations: true
-SpaceAfterCStyleCast: false
-SpaceAfterTemplateKeyword: false
-SpaceBeforeAssignmentOperators: true
-SpaceBeforeParens: ControlStatements
-SpaceInEmptyParentheses: false
-SpacesBeforeTrailingComments: 1
-SpacesInAngles:  false
-SpacesInContainerLiterals: true
-SpacesInCStyleCastParentheses: false
-SpacesInParentheses: false
-SpacesInSquareBrackets: false
-Standard:        Cpp11
-TabWidth:        8
+TabWidth:        4
 UseTab:          Never
+ColumnLimit:     100
+AlignAfterOpenBracket: Align
+BinPackParameters: false
+AlignEscapedNewlines: Left
+AlwaysBreakTemplateDeclarations: Yes
+PackConstructorInitializers: Never
+BreakConstructorInitializersBeforeComma: false
+IndentPPDirectives: BeforeHash
+SortIncludes:    Never
 ...
 

.clang-tidy

@@ -2,7 +2,7 @@ Checks: 'cppcoreguidelines-*,
 performance-*,
 modernize-*,
 google-*,
-misc-*,
+misc-*
 cert-*,
 readability-*,
 clang-analyzer-*,
@@ -27,7 +27,6 @@ clang-analyzer-*,
 
 WarningsAsErrors: ''
 HeaderFilterRegex: '*spdlog/[^f].*'
-AnalyzeTemporaryDtors: false
 FormatStyle:     none
 
 CheckOptions:    

.git-blame-ignore-revs

@@ -0,0 +1,6 @@
+# clang-format
+1a0bfc7a89f2d58e22605a4dc7e18a9a555b65aa
+95c226e9c92928e20ccdac0d060e7241859e282b
+9d52261185b5f2c454c381d626ec5c84d7b195f4
+4b2a8219d5d1b40062d030441adde7d1fb0d4f84
+0a53eafe18d983c7c8ba4cadd02d0cc7f7308f28

.github/workflows/coverity_scan.yml

@@ -0,0 +1,52 @@
+name: coverity-linux
+
+on: [push, pull_request]
+
+permissions:
+  contents: read
+
+jobs:
+  coverity_scan:
+    runs-on: ubuntu-latest
+    name: Coverity Scan
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Install dependencies
+        run: |
+          sudo apt-get update
+          sudo apt-get install -y curl build-essential cmake pkg-config libsystemd-dev
+
+      - name: Download Coverity Tool
+        run: |
+          curl -s -L --output coverity_tool.tgz "https://scan.coverity.com/download/linux64?token=${{ secrets.COVERITY_TOKEN }}&project=gabime%2Fspdlog"
+          mkdir coverity_tool
+          tar -C coverity_tool --strip-components=1 -xf coverity_tool.tgz
+          echo "$PWD/coverity_tool/bin" >> $GITHUB_PATH
+
+      - name: Build with Coverity
+        run: |
+          mkdir build && cd build
+          cmake .. -DCMAKE_BUILD_TYPE=Release -DCMAKE_CXX_STANDARD=17
+          cd ..
+          cov-build --dir cov-int make -C build -j4
+
+      - name: Submit results to Coverity
+        run: |
+          tar czf cov-int.tgz cov-int
+          response=$(curl --silent --show-error --fail \
+            --form email="${{ secrets.EMAIL }}" \
+            --form token="${{ secrets.COVERITY_TOKEN }}" \
+            --form file=@cov-int.tgz \
+            --form version="GitHub PR #${{ github.event.pull_request.number }}" \
+            --form description="CI run for PR" \
+            https://scan.coverity.com/builds?project=gabime%2Fspdlog)
+
+          echo "$response"
+
+          if echo "$response" | grep -qi "Build successfully submitted"; then
+            echo "Coverity upload succeeded"
+          else
+            echo "Coverity upload failed or was rejected"
+            exit 1
+          fi

.github/workflows/linux.yml

@@ -0,0 +1,87 @@
+name: linux
+
+on: [push, pull_request]
+
+permissions:
+  contents: read
+
+jobs:
+  # -----------------------------------------------------------------------
+  # Linux build matrix
+  # -----------------------------------------------------------------------
+  build:
+    runs-on: ubuntu-latest
+    defaults:
+      run:
+        shell: bash
+    strategy:
+      fail-fast: false
+      matrix:
+        config:
+          - { compiler: gcc, version: 7, build_type: Release, cppstd: 11 }
+          - { compiler: gcc, version: 9, build_type: Release, cppstd: 17 }
+          - { compiler: gcc, version: 11, build_type: Debug, cppstd: 20 }
+          - { compiler: gcc, version: 12, build_type: Release, cppstd: 20 }
+          - { compiler: gcc, version: 12, build_type: Debug, cppstd: 20, asan: ON }
+          - { compiler: clang, version: 12, build_type: Debug, cppstd: 17 }
+          - { compiler: clang, version: 15, build_type: Release, cppstd: 20, tsan: ON }
+    container:
+      image: ${{ matrix.config.compiler == 'clang' && 'teeks99/clang-ubuntu' || matrix.config.compiler }}:${{ matrix.config.version }}
+    name: "${{ matrix.config.compiler}} ${{ matrix.config.version }} (C++${{ matrix.config.cppstd }} ${{ matrix.config.build_type }} ${{ matrix.config.asan == 'ON' && 'ASAN' || '' }}${{ matrix.config.tsan == 'ON' && 'TSAN' || '' }})"
+    steps:
+      - uses: actions/checkout@v4
+      - name: Setup
+        run: |
+          apt-get update
+          apt-get install -y curl git pkg-config libsystemd-dev
+          CMAKE_VERSION="3.24.2"
+          curl -sSL https://github.com/Kitware/CMake/releases/download/v${CMAKE_VERSION}/cmake-${CMAKE_VERSION}-linux-x86_64.sh -o install-cmake.sh
+          chmod +x install-cmake.sh
+          ./install-cmake.sh --prefix=/usr/local --skip-license
+      - name: Setup Compiler
+        if: matrix.config.compiler == 'clang'
+        run: |
+          scripts/ci_setup_clang.sh "${{ matrix.config.version }}"
+          echo "CXXFLAGS=-stdlib=libc++" >> $GITHUB_ENV          
+          echo "CC=clang-${{ matrix.config.version }}" >> $GITHUB_ENV
+          echo "CXX=clang++-${{ matrix.config.version }}" >> $GITHUB_ENV
+      - name: Build
+        run: |
+          mkdir -p build && cd build
+          cmake .. \
+            -DCMAKE_BUILD_TYPE=${{ matrix.config.build_type }} \
+            -DCMAKE_CXX_STANDARD=${{ matrix.config.cppstd }} \
+            -DSPDLOG_BUILD_EXAMPLE=${{ matrix.config.examples || 'ON' }} \
+            -DSPDLOG_BUILD_EXAMPLE_HO=${{ matrix.config.examples || 'ON' }} \
+            -DSPDLOG_BUILD_WARNINGS=ON \
+            -DSPDLOG_BUILD_BENCH=OFF \
+            -DSPDLOG_BUILD_TESTS=ON \
+            -DSPDLOG_BUILD_TESTS_HO=OFF \
+            -DSPDLOG_SANITIZE_ADDRESS=${{ matrix.config.asan || 'OFF' }} \
+            -DSPDLOG_SANITIZE_THREAD=${{ matrix.config.tsan || 'OFF' }}
+          make -j 4
+          ctest -j 4 --output-on-failure
+
+  # -----------------------------------------------------------------------
+  # OS X build matrix
+  # -----------------------------------------------------------------------
+  build_osx:
+    runs-on: macOS-latest
+    name: "OS X Clang (C++11, Release)"
+    steps:
+      - uses: actions/checkout@v4
+      - name: Build
+        run: |
+          mkdir -p build && cd build
+          cmake .. \
+            -DCMAKE_BUILD_TYPE=Release \
+            -DCMAKE_CXX_STANDARD=11 \
+            -DSPDLOG_BUILD_EXAMPLE=ON \
+            -DSPDLOG_BUILD_EXAMPLE_HO=ON \
+            -DSPDLOG_BUILD_WARNINGS=ON \
+            -DSPDLOG_BUILD_BENCH=OFF \
+            -DSPDLOG_BUILD_TESTS=ON \
+            -DSPDLOG_BUILD_TESTS_HO=OFF \
+            -DSPDLOG_SANITIZE_ADDRESS=OFF
+          make -j 4
+          ctest -j 4 --output-on-failure

.github/workflows/macos.yml

@@ -0,0 +1,38 @@
+name: macos
+
+on: [push, pull_request]
+
+permissions:
+  contents: read
+
+jobs:
+  build:
+    runs-on: macOS-latest
+    name: "macOS Clang (C++11, Release)"
+    strategy:
+      fail-fast: true
+      matrix:
+        config:
+            - USE_STD_FORMAT: 'ON'
+              BUILD_EXAMPLE: 'OFF'
+            - USE_STD_FORMAT: 'OFF'
+              BUILD_EXAMPLE: 'ON'
+              
+    steps:
+      - uses: actions/checkout@v4
+      - name: Build
+        run: |
+          mkdir -p build && cd build
+          cmake .. \
+            -DCMAKE_BUILD_TYPE=Release \
+            -DCMAKE_CXX_STANDARD=11 \
+            -DSPDLOG_BUILD_EXAMPLE=${{ matrix.config.BUILD_EXAMPLE }} \
+            -DSPDLOG_BUILD_EXAMPLE_HO=${{ matrix.config.BUILD_EXAMPLE }} \
+            -DSPDLOG_BUILD_WARNINGS=ON \
+            -DSPDLOG_BUILD_BENCH=OFF \
+            -DSPDLOG_BUILD_TESTS=ON \
+            -DSPDLOG_BUILD_TESTS_HO=OFF \
+            -DSPDLOG_USE_STD_FORMAT=${{ matrix.config.USE_STD_FORMAT }} \
+            -DSPDLOG_SANITIZE_ADDRESS=OFF
+          make -j 4
+          ctest -j 4 --output-on-failure

.github/workflows/windows.yml

@@ -0,0 +1,148 @@
+name: windows
+
+on: [push, pull_request]
+
+permissions:
+  contents: read
+
+jobs:
+  build:
+    runs-on: windows-latest
+    strategy:
+      fail-fast: true
+      matrix:
+        config:
+          - GENERATOR: "Visual Studio 17 2022"
+            BUILD_TYPE: Release
+            BUILD_SHARED: 'ON'
+            FATAL_ERRORS: 'ON'
+            WCHAR: 'OFF'
+            WCHAR_FILES: 'OFF'
+            BUILD_EXAMPLE: 'OFF'
+            USE_STD_FORMAT: 'ON'
+            CXX_STANDARD: 20
+          - GENERATOR: "Visual Studio 17 2022"
+            BUILD_TYPE: Release
+            BUILD_SHARED: 'ON'
+            FATAL_ERRORS: 'ON'
+            WCHAR: 'ON'
+            WCHAR_FILES: 'ON'
+            BUILD_EXAMPLE: 'OFF'
+            USE_STD_FORMAT: 'ON'
+            CXX_STANDARD: 20
+          - GENERATOR: "Visual Studio 17 2022"
+            BUILD_TYPE: Release
+            BUILD_SHARED: 'ON'
+            FATAL_ERRORS: 'ON'
+            WCHAR: 'OFF'
+            WCHAR_FILES: 'OFF'
+            BUILD_EXAMPLE: 'ON'
+            USE_STD_FORMAT: 'OFF'
+            CXX_STANDARD: 17
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+
+      - name: CMake ${{ matrix.config.GENERATOR }} CXX=${{matrix.config.CXX_STANDARD}} WCHAR=${{matrix.config.WCHAR_FILES}} STD_FORMAT=${{matrix.config.USE_STD_FORMAT}}
+        shell: pwsh
+        run: |
+          mkdir build
+          cd build
+          cmake -G "${{ matrix.config.GENERATOR }}"  -A x64 `
+            -D CMAKE_BUILD_TYPE=${{ matrix.config.BUILD_TYPE }} `
+            -D BUILD_SHARED_LIBS=${{ matrix.config.BUILD_SHARED }} `
+            -D SPDLOG_WCHAR_SUPPORT=${{ matrix.config.WCHAR }} `
+            -D SPDLOG_WCHAR_FILENAMES=${{ matrix.config.WCHAR_FILES }} `
+            -D SPDLOG_BUILD_EXAMPLE=${{ matrix.config.BUILD_EXAMPLE }} `
+            -D SPDLOG_BUILD_EXAMPLE_HO=${{ matrix.config.BUILD_EXAMPLE }} `
+            -D SPDLOG_BUILD_TESTS=ON `
+            -D SPDLOG_BUILD_TESTS_HO=OFF `
+            -D SPDLOG_BUILD_WARNINGS=${{ matrix.config.FATAL_ERRORS }} `
+            -D SPDLOG_USE_STD_FORMAT=${{ matrix.config.USE_STD_FORMAT }} `
+            -D CMAKE_CXX_STANDARD=${{ matrix.config.CXX_STANDARD }} ..
+
+      - name: Build
+        shell: pwsh
+        run: |
+          cd build
+          cmake --build  . --parallel --config ${{ matrix.config.BUILD_TYPE }}
+
+      - name: Run Tests
+        shell: pwsh
+        env:
+          PATH: ${{ env.PATH }};${{ github.workspace }}\build\_deps\catch2-build\src\${{ matrix.config.BUILD_TYPE }};${{ github.workspace }}\build\${{ matrix.config.BUILD_TYPE }}
+        run: |
+          build\tests\${{ matrix.config.BUILD_TYPE }}\spdlog-utests.exe
+
+  # -----------------------------------------------------------------------
+  # MSVC 2019 build matrix
+  # -----------------------------------------------------------------------
+  build_2019:
+    runs-on: windows-2019
+    strategy:
+      fail-fast: true
+      matrix:
+        config:
+          - GENERATOR: "Visual Studio 16 2019"
+            BUILD_TYPE: Release
+            BUILD_SHARED: 'ON'
+            FATAL_ERRORS: 'ON'
+            WCHAR: 'OFF'
+            WCHAR_FILES: 'OFF'
+            BUILD_EXAMPLE: 'ON'
+            USE_STD_FORMAT: 'OFF'
+            CXX_STANDARD: 17
+          - GENERATOR: "Visual Studio 16 2019"
+            BUILD_TYPE: Release
+            BUILD_SHARED: 'ON'
+            FATAL_ERRORS: 'ON'
+            WCHAR: 'OFF'
+            WCHAR_FILES: 'OFF'
+            BUILD_EXAMPLE: 'ON'
+            USE_STD_FORMAT: 'OFF'
+            CXX_STANDARD: 14
+          - GENERATOR: "Visual Studio 16 2019"
+            BUILD_TYPE: Release
+            BUILD_SHARED: 'ON'
+            FATAL_ERRORS: 'ON'
+            WCHAR: 'OFF'
+            WCHAR_FILES: 'OFF'
+            BUILD_EXAMPLE: 'ON'
+            USE_STD_FORMAT: 'OFF'
+            CXX_STANDARD: 11
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+
+      - name: CMake ${{ matrix.config.GENERATOR }} CXX=${{matrix.config.CXX_STANDARD}} WCHAR=${{matrix.config.WCHAR_FILES}} STD_FORMAT=${{matrix.config.USE_STD_FORMAT}}
+        shell: pwsh
+        run: |
+          mkdir build
+          cd build
+          cmake -G "${{ matrix.config.GENERATOR }}"  -A x64 `
+            -D CMAKE_BUILD_TYPE=${{ matrix.config.BUILD_TYPE }} `
+            -D BUILD_SHARED_LIBS=${{ matrix.config.BUILD_SHARED }} `
+            -D SPDLOG_WCHAR_SUPPORT=${{ matrix.config.WCHAR }} `
+            -D SPDLOG_WCHAR_FILENAMES=${{ matrix.config.WCHAR_FILES }} `
+            -D SPDLOG_BUILD_EXAMPLE=${{ matrix.config.BUILD_EXAMPLE }} `
+            -D SPDLOG_BUILD_EXAMPLE_HO=${{ matrix.config.BUILD_EXAMPLE }} `
+            -D SPDLOG_BUILD_TESTS=ON `
+            -D SPDLOG_BUILD_TESTS_HO=OFF `
+            -D SPDLOG_BUILD_WARNINGS=${{ matrix.config.FATAL_ERRORS }} `
+            -D SPDLOG_USE_STD_FORMAT=${{ matrix.config.USE_STD_FORMAT }} `
+            -D CMAKE_CXX_STANDARD=${{ matrix.config.CXX_STANDARD }} ..
+
+      - name: Build
+        shell: pwsh
+        run: |
+          cd build
+          cmake --build  . --parallel --config ${{ matrix.config.BUILD_TYPE }}
+
+      - name: Run Tests
+        shell: pwsh
+        env:
+          PATH: ${{ env.PATH }};${{ github.workspace }}\build\_deps\catch2-build\src\${{ matrix.config.BUILD_TYPE }};${{ github.workspace }}\build\${{ matrix.config.BUILD_TYPE }}
+        run: |
+          build\tests\${{ matrix.config.BUILD_TYPE }}\spdlog-utests.exe

.gitignore

@@ -1,4 +1,6 @@
 # Auto generated files
+[Dd]ebug/
+[Rr]elease/
 build/*
 *.slo
 *.lo
@@ -55,6 +57,7 @@ example/*
 
 # generated files
 generated
+version.rc
 
 # Cmake
 CMakeCache.txt
@@ -67,9 +70,14 @@ install_manifest.txt
 /tests/tests.VC.db
 /tests/tests
 /tests/logs/*
+spdlogConfig.cmake
+spdlogConfigVersion.cmake
+compile_commands.json
 
 # idea
 .idea/
+.cache/
+.vscode/
 cmake-build-*/
 *.db
 *.ipch
@@ -81,3 +89,10 @@ cmake-build-*/
 *.tcl
 *.user
 *.sln
+
+# macos
+*.DS_store
+*.xcodeproj/
+/.vs
+/out/build
+/CMakeSettings.json

.travis.yml

@@ -1,112 +0,0 @@
-# Adapted from various sources, including:
-# - Louis Dionne's Hana: https://github.com/ldionne/hana
-# - Paul Fultz II's FIT: https://github.com/pfultz2/Fit
-# - Eric Niebler's range-v3: https://github.com/ericniebler/range-v3
-sudo: required
-language: cpp
-
-# gcc 4.8
-addons: &gcc48
-  apt:
-    packages:
-      - g++-4.8
-    sources:
-      - ubuntu-toolchain-r-test
-
-# gcc 7.0
-addons: &gcc7
-  apt:
-    packages:
-      - g++-7
-    sources:
-      - ubuntu-toolchain-r-test
-
-# Clang 3.5
-addons: &clang35
-  apt:
-    packages:
-      - clang-3.5
-    sources:
-      - ubuntu-toolchain-r-test
-      - llvm-toolchain-precise-3.5
-      
-
-addons: &clang10
-  apt:
-    packages:
-      - clang-10
-      - lldb-10
-      - lld-10
-    sources:
-      - sourceline: "deb http://apt.llvm.org/bionic/ llvm-toolchain-bionic-10 main"
-        key_url: "https://apt.llvm.org/llvm-snapshot.gpg.key"
-
-
-matrix:
-  include:
-    # Test gcc-4.8: C++11, Build=Debug/Release
-    - env: GCC_VERSION=4.8 BUILD_TYPE=Debug CPP=11
-      os: linux
-      addons: *gcc48
-
-    - env: GCC_VERSION=4.8 BUILD_TYPE=Release CPP=11
-      os: linux
-      addons: *gcc48
-
-    - env: GCC_VERSION=7 BUILD_TYPE=Release CPP=11
-      os: linux
-      addons: *gcc7
-
-    # Test clang-3.5: C++11, Build=Debug/Release
-    - env: CLANG_VERSION=3.5 BUILD_TYPE=Debug CPP=11
-      os: linux
-      addons: *clang35
-
-    - env: CLANG_VERSION=3.5 BUILD_TYPE=Release CPP=11
-      os: linux
-      addons: *clang35
-
-      # osx
-    - env: BUILD_TYPE=Release CPP=11 ASAN=Off TSAN=Off
-      os: osx
-
-    # Test clang-10.0: C++11, Build=Debug/Release
-    - env: CLANG_VERSION=10 BUILD_TYPE=Debug CPP=11
-      os: linux
-      dist: bionic
-      addons: *clang10
-
-    - env: CLANG_VERSION=10 BUILD_TYPE=Release CPP=11 ASAN=On
-      os: linux
-      dist: bionic
-      addons: *clang10
-
-
-before_script:
-  - if [ -n "$GCC_VERSION" ]; then export CXX="g++-${GCC_VERSION}" CC="gcc-${GCC_VERSION}"; fi
-  - if [ -n "$CLANG_VERSION" ]; then export CXX="clang++-${CLANG_VERSION}" CC="clang-${CLANG_VERSION}"; fi
-  - if [[ "$TRAVIS_OS_NAME" == "osx" ]]; then export CXX="clang++" CC="clang"; fi
-  - which $CXX
-  - which $CC
-  - $CXX --version
-  - cmake --version
-
-script:
-  - cd ${TRAVIS_BUILD_DIR}
-  - mkdir -p build && cd build
-  - |
-    cmake .. \
-      --warn-uninitialized \
-      -DCMAKE_BUILD_TYPE=$BUILD_TYPE \
-      -DCMAKE_CXX_STANDARD=$CPP \
-      -DSPDLOG_BUILD_EXAMPLE=ON \
-      -DSPDLOG_BUILD_EXAMPLE_HO=ON \
-      -DSPDLOG_ENABLE_WARNINGS=ON \
-      -DSPDLOG_BUILD_BENCH=OFF \
-      -DSPDLOG_BUILD_TESTS=ON \
-      -DSPDLOG_BUILD_TESTS_HO=OFf \
-      -DSPDLOG_SANITIZE_ADDRESS=$ASAN 
-      
-  - make VERBOSE=1 -j2
-  - ctest -j2 --output-on-failure
-  

CMakeLists.txt

@@ -1,14 +1,6 @@
 # Copyright(c) 2019 spdlog authors Distributed under the MIT License (http://opensource.org/licenses/MIT)
 
-cmake_minimum_required(VERSION 3.2)
-
-if(${CMAKE_VERSION} VERSION_LESS 3.11)
-    cmake_policy(VERSION ${CMAKE_MAJOR_VERSION}.${CMAKE_MINOR_VERSION})
-else()
-    cmake_policy(VERSION 3.11)
-endif()
-
-enable_language(C)
+cmake_minimum_required(VERSION 3.10...3.21)
 
 # ---------------------------------------------------------------------------------------
 # Start spdlog project
@@ -26,21 +18,24 @@ include(GNUInstallDirs)
 # ---------------------------------------------------------------------------------------
 # Set default build to release
 # ---------------------------------------------------------------------------------------
-if(NOT CMAKE_BUILD_TYPE)
+if(NOT CMAKE_BUILD_TYPE AND NOT CMAKE_CONFIGURATION_TYPES)
     set(CMAKE_BUILD_TYPE "Release" CACHE STRING "Choose Release or Debug" FORCE)
 endif()
 
 # ---------------------------------------------------------------------------------------
 # Compiler config
 # ---------------------------------------------------------------------------------------
-if(NOT CMAKE_CXX_STANDARD)
+if(SPDLOG_USE_STD_FORMAT)
+    set(CMAKE_CXX_STANDARD 20)
+    set(CMAKE_CXX_STANDARD_REQUIRED ON)
+elseif(NOT CMAKE_CXX_STANDARD)
     set(CMAKE_CXX_STANDARD 11)
     set(CMAKE_CXX_STANDARD_REQUIRED ON)
 endif()
 
 set(CMAKE_CXX_EXTENSIONS OFF)
 
-if(CMAKE_SYSTEM_NAME MATCHES "CYGWIN")
+if(CMAKE_SYSTEM_NAME MATCHES "CYGWIN" OR CMAKE_SYSTEM_NAME MATCHES "MSYS" OR CMAKE_SYSTEM_NAME MATCHES "MINGW")
     set(CMAKE_CXX_EXTENSIONS ON)
 endif()
 
@@ -64,6 +59,9 @@ option(SPDLOG_BUILD_SHARED "Build shared library" OFF)
 # precompiled headers option
 option(SPDLOG_ENABLE_PCH "Build static or shared library using precompiled header to speed up compilation time" OFF)
 
+# build position independent code
+option(SPDLOG_BUILD_PIC "Build position independent code (-fPIC)" OFF)
+
 # example options
 option(SPDLOG_BUILD_EXAMPLE "Build example" ${SPDLOG_MASTER_PROJECT})
 option(SPDLOG_BUILD_EXAMPLE_HO "Build header only example" OFF)
@@ -77,12 +75,18 @@ option(SPDLOG_BUILD_BENCH "Build benchmarks (Requires https://github.com/google/
 
 # sanitizer options
 option(SPDLOG_SANITIZE_ADDRESS "Enable address sanitizer in tests" OFF)
+option(SPDLOG_SANITIZE_THREAD "Enable thread sanitizer in tests" OFF)
+if(SPDLOG_SANITIZE_ADDRESS AND SPDLOG_SANITIZE_THREAD)
+    message(FATAL_ERROR "SPDLOG_SANITIZE_ADDRESS and SPDLOG_SANITIZE_THREAD are mutually exclusive")
+endif()
 
 # warning options
 option(SPDLOG_BUILD_WARNINGS "Enable compiler warnings" OFF)
 
 # install options
+option(SPDLOG_SYSTEM_INCLUDES "Include as system headers (skip for clang-tidy)." OFF)
 option(SPDLOG_INSTALL "Generate the install target" ${SPDLOG_MASTER_PROJECT})
+option(SPDLOG_USE_STD_FORMAT "Use std::format instead of fmt library." OFF)
 option(SPDLOG_FMT_EXTERNAL "Use external fmt library instead of bundled" OFF)
 option(SPDLOG_FMT_EXTERNAL_HO "Use external fmt header-only library instead of bundled" OFF)
 option(SPDLOG_NO_EXCEPTIONS "Compile with -fno-exceptions. Call abort() on any spdlog exceptions" OFF)
@@ -91,14 +95,33 @@ if(SPDLOG_FMT_EXTERNAL AND SPDLOG_FMT_EXTERNAL_HO)
     message(FATAL_ERROR "SPDLOG_FMT_EXTERNAL and SPDLOG_FMT_EXTERNAL_HO are mutually exclusive")
 endif()
 
+if(SPDLOG_USE_STD_FORMAT AND SPDLOG_FMT_EXTERNAL_HO)
+    message(FATAL_ERROR "SPDLOG_USE_STD_FORMAT and SPDLOG_FMT_EXTERNAL_HO are mutually exclusive")
+endif()
+
+if(SPDLOG_USE_STD_FORMAT AND SPDLOG_FMT_EXTERNAL)
+    message(FATAL_ERROR "SPDLOG_USE_STD_FORMAT and SPDLOG_FMT_EXTERNAL are mutually exclusive")
+endif()
+
 # misc tweakme options
 if(WIN32)
     option(SPDLOG_WCHAR_SUPPORT "Support wchar api" OFF)
     option(SPDLOG_WCHAR_FILENAMES "Support wchar filenames" OFF)
+    option(SPDLOG_WCHAR_CONSOLE "Support wchar output to console" OFF)
+else()
+    set(SPDLOG_WCHAR_SUPPORT OFF CACHE BOOL "non supported option" FORCE)
+    set(SPDLOG_WCHAR_FILENAMES OFF CACHE BOOL "non supported option" FORCE)
+    set(SPDLOG_WCHAR_CONSOLE OFF CACHE BOOL "non supported option" FORCE)
 endif()
+
+if(MSVC)
+    option(SPDLOG_MSVC_UTF8 "Enable/disable msvc /utf-8 flag required by fmt lib" ON)
+endif()
+
 if(${CMAKE_SYSTEM_NAME} STREQUAL "Linux")
-    option(SPDLOG_CLOCK_COARSE
-           "Use the much faster (but much less accurate) CLOCK_REALTIME_COARSE instead of the regular clock," OFF)
+    option(SPDLOG_CLOCK_COARSE "Use CLOCK_REALTIME_COARSE instead of the regular clock," OFF)
+else()
+    set(SPDLOG_CLOCK_COARSE OFF CACHE BOOL "non supported option" FORCE)
 endif()
 
 option(SPDLOG_PREVENT_CHILD_FD "Prevent from child processes to inherit log file descriptors" OFF)
@@ -108,11 +131,11 @@ option(
     SPDLOG_NO_ATOMIC_LEVELS
     "prevent spdlog from using of std::atomic log levels (use only if your code never modifies log levels concurrently"
     OFF)
+option(SPDLOG_DISABLE_DEFAULT_LOGGER "Disable default logger creation" OFF)
+option(SPDLOG_FWRITE_UNLOCKED "Use the unlocked variant of fwrite. Leave this on unless your libc doesn't have it" ON)
 
 # clang-tidy
-if(${CMAKE_VERSION} VERSION_GREATER "3.5")
-    option(SPDLOG_TIDY "run clang-tidy" OFF)
-endif()
+option(SPDLOG_TIDY "run clang-tidy" OFF)
 
 if(SPDLOG_TIDY)
     set(CMAKE_CXX_CLANG_TIDY "clang-tidy")
@@ -120,30 +143,34 @@ if(SPDLOG_TIDY)
     message(STATUS "Enabled clang-tidy")
 endif()
 
+if(SPDLOG_BUILD_PIC)
+    set(CMAKE_POSITION_INDEPENDENT_CODE ON)
+endif()
+
 find_package(Threads REQUIRED)
 message(STATUS "Build type: " ${CMAKE_BUILD_TYPE})
 # ---------------------------------------------------------------------------------------
-# Static/Shared library (shared not supported in windows yet)
+# Static/Shared library
 # ---------------------------------------------------------------------------------------
 set(SPDLOG_SRCS src/spdlog.cpp src/stdout_sinks.cpp src/color_sinks.cpp src/file_sinks.cpp src/async.cpp src/cfg.cpp)
 
-if(NOT SPDLOG_FMT_EXTERNAL AND NOT SPDLOG_FMT_EXTERNAL_HO)
-    list(APPEND SPDLOG_SRCS src/fmt.cpp)
+if(NOT SPDLOG_USE_STD_FORMAT AND NOT SPDLOG_FMT_EXTERNAL AND NOT SPDLOG_FMT_EXTERNAL_HO)
+    list(APPEND SPDLOG_SRCS src/bundled_fmtlib_format.cpp)
 endif()
 
-if(WIN32 AND SPDLOG_BUILD_SHARED)
-    list(APPEND SPDLOG_SRCS ${CMAKE_CURRENT_BINARY_DIR}/version.rc)
-endif()
-
-if(SPDLOG_BUILD_SHARED)
+if(SPDLOG_BUILD_SHARED OR BUILD_SHARED_LIBS)
+    if(WIN32)
+        configure_file(${CMAKE_CURRENT_SOURCE_DIR}/cmake/version.rc.in ${CMAKE_CURRENT_BINARY_DIR}/version.rc @ONLY)
+        list(APPEND SPDLOG_SRCS ${CMAKE_CURRENT_BINARY_DIR}/version.rc)
+    endif()
     add_library(spdlog SHARED ${SPDLOG_SRCS} ${SPDLOG_ALL_HEADERS})
     target_compile_definitions(spdlog PUBLIC SPDLOG_SHARED_LIB)
-    if(WIN32)
-        target_compile_options(spdlog PUBLIC /wd4251 /wd4275)
-        configure_file(${CMAKE_CURRENT_SOURCE_DIR}/cmake/version.rc.in ${CMAKE_CURRENT_BINARY_DIR}/version.rc @ONLY)
+    if(CMAKE_CXX_COMPILER_ID STREQUAL "MSVC")
+        target_compile_options(spdlog PUBLIC $<$<AND:$<CXX_COMPILER_ID:MSVC>,$<NOT:$<COMPILE_LANGUAGE:CUDA>>>:/wd4251
+                                             /wd4275>)
     endif()
-    if(NOT SPDLOG_FMT_EXTERNAL AND NOT SPDLOG_FMT_EXTERNAL_HO)
-        target_compile_definitions(spdlog PRIVATE FMT_EXPORT PUBLIC FMT_SHARED)
+    if(NOT SPDLOG_USE_STD_FORMAT AND NOT SPDLOG_FMT_EXTERNAL AND NOT SPDLOG_FMT_EXTERNAL_HO)
+        target_compile_definitions(spdlog PRIVATE FMT_LIB_EXPORT PUBLIC FMT_SHARED)
     endif()
 else()
     add_library(spdlog STATIC ${SPDLOG_SRCS} ${SPDLOG_ALL_HEADERS})
@@ -151,13 +178,19 @@ endif()
 
 add_library(spdlog::spdlog ALIAS spdlog)
 
+set(SPDLOG_INCLUDES_LEVEL "")
+if(SPDLOG_SYSTEM_INCLUDES)
+    set(SPDLOG_INCLUDES_LEVEL "SYSTEM")
+endif()
+
 target_compile_definitions(spdlog PUBLIC SPDLOG_COMPILED_LIB)
-target_include_directories(spdlog PUBLIC "$<BUILD_INTERFACE:${CMAKE_CURRENT_LIST_DIR}/include>"
-                                         "$<INSTALL_INTERFACE:${CMAKE_INSTALL_INCLUDEDIR}>")
+target_include_directories(spdlog ${SPDLOG_INCLUDES_LEVEL} PUBLIC "$<BUILD_INTERFACE:${CMAKE_CURRENT_LIST_DIR}/include>"
+                                                                  "$<INSTALL_INTERFACE:${CMAKE_INSTALL_INCLUDEDIR}>")
 target_link_libraries(spdlog PUBLIC Threads::Threads)
 spdlog_enable_warnings(spdlog)
 
-set_target_properties(spdlog PROPERTIES VERSION ${SPDLOG_VERSION} SOVERSION ${SPDLOG_VERSION_MAJOR})
+set_target_properties(spdlog PROPERTIES VERSION ${SPDLOG_VERSION} SOVERSION
+                                                                  ${SPDLOG_VERSION_MAJOR}.${SPDLOG_VERSION_MINOR})
 set_target_properties(spdlog PROPERTIES DEBUG_POSTFIX d)
 
 if(COMMAND target_precompile_headers AND SPDLOG_ENABLE_PCH)
@@ -165,14 +198,22 @@ if(COMMAND target_precompile_headers AND SPDLOG_ENABLE_PCH)
     target_precompile_headers(spdlog PRIVATE ${PROJECT_BINARY_DIR}/spdlog_pch.h)
 endif()
 
+# sanitizer support
+if(SPDLOG_SANITIZE_ADDRESS)
+    spdlog_enable_addr_sanitizer(spdlog)
+elseif(SPDLOG_SANITIZE_THREAD)
+    spdlog_enable_thread_sanitizer(spdlog)
+endif()
+
 # ---------------------------------------------------------------------------------------
 # Header only version
 # ---------------------------------------------------------------------------------------
 add_library(spdlog_header_only INTERFACE)
 add_library(spdlog::spdlog_header_only ALIAS spdlog_header_only)
 
-target_include_directories(spdlog_header_only INTERFACE "$<BUILD_INTERFACE:${CMAKE_CURRENT_LIST_DIR}/include>"
-                                                        "$<INSTALL_INTERFACE:${CMAKE_INSTALL_INCLUDEDIR}>")
+target_include_directories(
+    spdlog_header_only ${SPDLOG_INCLUDES_LEVEL} INTERFACE "$<BUILD_INTERFACE:${CMAKE_CURRENT_LIST_DIR}/include>"
+                                                          "$<INSTALL_INTERFACE:${CMAKE_INSTALL_INCLUDEDIR}>")
 target_link_libraries(spdlog_header_only INTERFACE Threads::Threads)
 
 # ---------------------------------------------------------------------------------------
@@ -180,12 +221,12 @@ target_link_libraries(spdlog_header_only INTERFACE Threads::Threads)
 # ---------------------------------------------------------------------------------------
 if(SPDLOG_FMT_EXTERNAL OR SPDLOG_FMT_EXTERNAL_HO)
     if(NOT TARGET fmt::fmt)
-        find_package(fmt 5.3.0 REQUIRED)
+        find_package(fmt CONFIG REQUIRED)
     endif()
     target_compile_definitions(spdlog PUBLIC SPDLOG_FMT_EXTERNAL)
     target_compile_definitions(spdlog_header_only INTERFACE SPDLOG_FMT_EXTERNAL)
 
-    # use external fmt-header-nly
+    # use external fmt-header-only
     if(SPDLOG_FMT_EXTERNAL_HO)
         target_link_libraries(spdlog PUBLIC fmt::fmt-header-only)
         target_link_libraries(spdlog_header_only INTERFACE fmt::fmt-header-only)
@@ -198,53 +239,80 @@ if(SPDLOG_FMT_EXTERNAL OR SPDLOG_FMT_EXTERNAL_HO)
 endif()
 
 # ---------------------------------------------------------------------------------------
-# Misc definitions according to tweak options
+# Check if fwrite_unlocked/_fwrite_nolock is available
 # ---------------------------------------------------------------------------------------
-if(SPDLOG_WCHAR_SUPPORT)
-    target_compile_definitions(spdlog PUBLIC SPDLOG_WCHAR_TO_UTF8_SUPPORT)
-    target_compile_definitions(spdlog_header_only INTERFACE SPDLOG_WCHAR_TO_UTF8_SUPPORT)
-endif()
-
-if(SPDLOG_WCHAR_FILENAMES)
-    target_compile_definitions(spdlog PUBLIC SPDLOG_WCHAR_FILENAMES)
-    target_compile_definitions(spdlog_header_only INTERFACE SPDLOG_WCHAR_FILENAMES)
-endif()
-
-if(SPDLOG_NO_EXCEPTIONS)
-    target_compile_definitions(spdlog PUBLIC SPDLOG_NO_EXCEPTIONS)
-
-    target_compile_definitions(spdlog_header_only INTERFACE SPDLOG_NO_EXCEPTIONS)
-
-    if(NOT MSVC)
-        target_compile_options(spdlog PRIVATE -fno-exceptions)
+if(SPDLOG_FWRITE_UNLOCKED)
+    include(CheckSymbolExists)
+    if(WIN32)
+        check_symbol_exists(_fwrite_nolock "stdio.h" HAVE_FWRITE_UNLOCKED)
+    else()
+        check_symbol_exists(fwrite_unlocked "stdio.h" HAVE_FWRITE_UNLOCKED)
+    endif()
+    if(HAVE_FWRITE_UNLOCKED)
+        target_compile_definitions(spdlog PRIVATE SPDLOG_FWRITE_UNLOCKED)
+        target_compile_definitions(spdlog_header_only INTERFACE SPDLOG_FWRITE_UNLOCKED)
     endif()
 endif()
 
-if(SPDLOG_CLOCK_COARSE)
-    target_compile_definitions(spdlog PRIVATE SPDLOG_CLOCK_COARSE)
-    target_compile_definitions(spdlog_header_only INTERFACE SPDLOG_CLOCK_COARSE)
+# ---------------------------------------------------------------------------------------
+# Add required libraries for Android CMake build
+# ---------------------------------------------------------------------------------------
+if(ANDROID)
+    target_link_libraries(spdlog PUBLIC log)
+    target_link_libraries(spdlog_header_only INTERFACE log)
 endif()
 
-if(SPDLOG_PREVENT_CHILD_FD)
-    target_compile_definitions(spdlog PRIVATE SPDLOG_PREVENT_CHILD_FD)
-    target_compile_definitions(spdlog_header_only INTERFACE SPDLOG_PREVENT_CHILD_FD)
+# ---------------------------------------------------------------------------------------
+# Misc definitions according to tweak options
+# ---------------------------------------------------------------------------------------
+set(SPDLOG_WCHAR_TO_UTF8_SUPPORT ${SPDLOG_WCHAR_SUPPORT})
+set(SPDLOG_UTF8_TO_WCHAR_CONSOLE ${SPDLOG_WCHAR_CONSOLE})
+foreach(
+    SPDLOG_OPTION
+    SPDLOG_WCHAR_TO_UTF8_SUPPORT
+    SPDLOG_UTF8_TO_WCHAR_CONSOLE
+    SPDLOG_WCHAR_FILENAMES
+    SPDLOG_NO_EXCEPTIONS
+    SPDLOG_CLOCK_COARSE
+    SPDLOG_PREVENT_CHILD_FD
+    SPDLOG_NO_THREAD_ID
+    SPDLOG_NO_TLS
+    SPDLOG_NO_ATOMIC_LEVELS
+    SPDLOG_DISABLE_DEFAULT_LOGGER
+    SPDLOG_USE_STD_FORMAT)
+    if(${SPDLOG_OPTION})
+        target_compile_definitions(spdlog PUBLIC ${SPDLOG_OPTION})
+        target_compile_definitions(spdlog_header_only INTERFACE ${SPDLOG_OPTION})
+    endif()
+endforeach()
+
+if(MSVC)
+    target_compile_options(spdlog PRIVATE "/Zc:__cplusplus")
+    target_compile_options(spdlog_header_only INTERFACE "/Zc:__cplusplus")
+    if(SPDLOG_MSVC_UTF8)
+        # fmtlib requires the /utf-8 flag when building with msvc. see https://github.com/fmtlib/fmt/pull/4159 on the
+        # purpose of the additional
+        # "$<$<AND:$<COMPILE_LANGUAGE:CXX>,$<CXX_COMPILER_ID:MSVC>>"
+        target_compile_options(spdlog PUBLIC $<$<AND:$<COMPILE_LANGUAGE:CXX>,$<CXX_COMPILER_ID:MSVC>>:/utf-8>)
+        target_compile_options(spdlog_header_only
+                               INTERFACE $<$<AND:$<COMPILE_LANGUAGE:CXX>,$<CXX_COMPILER_ID:MSVC>>:/utf-8>)
+    endif()
 endif()
 
-if(SPDLOG_NO_THREAD_ID)
-    target_compile_definitions(spdlog PRIVATE SPDLOG_NO_THREAD_ID)
-    target_compile_definitions(spdlog_header_only INTERFACE SPDLOG_NO_THREAD_ID)
+# ---------------------------------------------------------------------------------------
+# If exceptions are disabled, disable them in the bundled fmt as well
+# ---------------------------------------------------------------------------------------
+if(SPDLOG_NO_EXCEPTIONS)
+    if(NOT SPDLOG_FMT_EXTERNAL AND NOT SPDLOG_FMT_EXTERNAL_HO)
+        target_compile_definitions(spdlog PUBLIC FMT_USE_EXCEPTIONS=0)
+    endif()
+    if(NOT MSVC)
+        target_compile_options(spdlog PRIVATE -fno-exceptions)
+    else()
+        target_compile_options(spdlog PRIVATE /EHs-c-)
+        target_compile_definitions(spdlog PRIVATE _HAS_EXCEPTIONS=0)
+    endif()
 endif()
-
-if(SPDLOG_NO_TLS)
-    target_compile_definitions(spdlog PRIVATE SPDLOG_NO_TLS)
-    target_compile_definitions(spdlog_header_only INTERFACE SPDLOG_NO_TLS)
-endif()
-
-if(SPDLOG_NO_ATOMIC_LEVELS)
-    target_compile_definitions(spdlog PUBLIC SPDLOG_NO_ATOMIC_LEVELS)
-    target_compile_definitions(spdlog_header_only INTERFACE SPDLOG_NO_ATOMIC_LEVELS)
-endif()
-
 # ---------------------------------------------------------------------------------------
 # Build binaries
 # ---------------------------------------------------------------------------------------
@@ -292,7 +360,7 @@ if(SPDLOG_INSTALL)
         ARCHIVE DESTINATION ${CMAKE_INSTALL_LIBDIR}
         RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR})
 
-    if(NOT SPDLOG_FMT_EXTERNAL AND NOT SPDLOG_FMT_EXTERNAL_HO)
+    if(NOT SPDLOG_USE_STD_FORMAT AND NOT SPDLOG_FMT_EXTERNAL AND NOT SPDLOG_FMT_EXTERNAL_HO)
         install(DIRECTORY include/${PROJECT_NAME}/fmt/bundled/
                 DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}/${PROJECT_NAME}/fmt/bundled/")
     endif()
@@ -300,6 +368,16 @@ if(SPDLOG_INSTALL)
     # ---------------------------------------------------------------------------------------
     # Install pkg-config file
     # ---------------------------------------------------------------------------------------
+    if(IS_ABSOLUTE "${CMAKE_INSTALL_INCLUDEDIR}")
+        set(PKG_CONFIG_INCLUDEDIR "${CMAKE_INSTALL_INCLUDEDIR}")
+    else()
+        set(PKG_CONFIG_INCLUDEDIR "\${prefix}/${CMAKE_INSTALL_INCLUDEDIR}")
+    endif()
+    if(IS_ABSOLUTE "${CMAKE_INSTALL_LIBDIR}")
+        set(PKG_CONFIG_LIBDIR "${CMAKE_INSTALL_LIBDIR}")
+    else()
+        set(PKG_CONFIG_LIBDIR "\${exec_prefix}/${CMAKE_INSTALL_LIBDIR}")
+    endif()
     get_target_property(PKG_CONFIG_DEFINES spdlog INTERFACE_COMPILE_DEFINITIONS)
     string(REPLACE ";" " -D" PKG_CONFIG_DEFINES "${PKG_CONFIG_DEFINES}")
     string(CONCAT PKG_CONFIG_DEFINES "-D" "${PKG_CONFIG_DEFINES}")
@@ -309,10 +387,12 @@ if(SPDLOG_INSTALL)
     # ---------------------------------------------------------------------------------------
     # Install CMake config files
     # ---------------------------------------------------------------------------------------
+    export(TARGETS spdlog spdlog_header_only NAMESPACE spdlog::
+           FILE "${CMAKE_CURRENT_BINARY_DIR}/${config_targets_file}")
     install(EXPORT spdlog DESTINATION ${export_dest_dir} NAMESPACE spdlog:: FILE ${config_targets_file})
 
     include(CMakePackageConfigHelpers)
-    configure_file("${project_config_in}" "${project_config_out}" @ONLY)
+    configure_package_config_file("${project_config_in}" "${project_config_out}" INSTALL_DESTINATION ${export_dest_dir})
 
     write_basic_package_version_file("${version_config_file}" COMPATIBILITY SameMajorVersion)
     install(FILES "${project_config_out}" "${version_config_file}" DESTINATION "${export_dest_dir}")

INSTALL

@@ -1,24 +1,27 @@
-Header only version:
+Header Only Version
 ==================================================================
-Just copy the files to your build tree and use a C++11 compiler.
+Just copy the files to your build tree and use a C++11 compiler.  
 Or use CMake:
+``` 
   add_executable(example_header_only example.cpp)
   target_link_libraries(example_header_only spdlog::spdlog_header_only)
+```
 
-
-Compiled library version:
+Compiled Library Version
 ==================================================================
 CMake:
+```  
   add_executable(example example.cpp)
   target_link_libraries(example spdlog::spdlog)
+```
 
-Or copy src/spdlog.cpp to your build tree and pass the -DSPDLOG_COMPILED_LIB to the compiler.
+Or copy files src/*.cpp to your build tree and pass the -DSPDLOG_COMPILED_LIB to the compiler.
 
-Tested on:
+Important Information for Compilation:
+==================================================================
+* If you encounter compilation errors with gcc 4.8.x, please note that gcc 4.8.x does not fully support C++11. In such cases, consider upgrading your compiler or using a different version that fully supports C++11 standards
+
+Tested on:  
 gcc 4.8.1 and above
 clang 3.5
-Visual Studio 2013
-
-
-
-
+Visual Studio 2013

LICENSE

@@ -22,5 +22,5 @@ THE SOFTWARE.
 
 -- NOTE: Third party dependency used by this software --
 This software depends on the fmt lib (MIT License),
-and users must comply to its license: https://github.com/fmtlib/fmt/blob/master/LICENSE.rst
+and users must comply to its license: https://raw.githubusercontent.com/fmtlib/fmt/master/LICENSE
 

README.md

@@ -1,62 +1,73 @@
 # spdlog
 
-Very fast, header-only/compiled, C++ logging library. [![Build Status](https://travis-ci.org/gabime/spdlog.svg?branch=v1.x)](https://travis-ci.org/gabime/spdlog)  [![Build status](https://ci.appveyor.com/api/projects/status/d2jnxclg20vd0o50?svg=true)](https://ci.appveyor.com/project/gabime/spdlog) [![Release](https://img.shields.io/github/release/gabime/spdlog.svg)](https://github.com/gabime/spdlog/releases/latest)
+ 
+[![ci](https://github.com/gabime/spdlog/actions/workflows/linux.yml/badge.svg)](https://github.com/gabime/spdlog/actions/workflows/linux.yml) 
+[![ci](https://github.com/gabime/spdlog/actions/workflows/windows.yml/badge.svg)](https://github.com/gabime/spdlog/actions/workflows/windows.yml) 
+[![ci](https://github.com/gabime/spdlog/actions/workflows/macos.yml/badge.svg)](https://github.com/gabime/spdlog/actions/workflows/macos.yml) 
+[![Build status](https://ci.appveyor.com/api/projects/status/d2jnxclg20vd0o50?svg=true&branch=v1.x)](https://ci.appveyor.com/project/gabime/spdlog) [![Release](https://img.shields.io/github/release/gabime/spdlog.svg)](https://github.com/gabime/spdlog/releases/latest)
 
-## Install 
-#### Header only version
-Copy the source [folder](https://github.com/gabime/spdlog/tree/v1.x/include/spdlog) to your build tree and use a C++11 compiler.
+Fast C++ logging library
 
-#### Static lib version (recommended - much faster compile times)
+
+## Install
+#### Header-only version
+Copy the include [folder](include/spdlog) to your build tree and use a C++11 compiler.
+
+#### Compiled version (recommended - much faster compile times)
 ```console
 $ git clone https://github.com/gabime/spdlog.git
 $ cd spdlog && mkdir build && cd build
-$ cmake .. && make -j
+$ cmake .. && cmake --build .
 ```
-      
-   see example [CMakeLists.txt](https://github.com/gabime/spdlog/blob/v1.x/example/CMakeLists.txt) on how to use.
+see example [CMakeLists.txt](example/CMakeLists.txt) on how to use.
 
 ## Platforms
- * Linux, FreeBSD, OpenBSD, Solaris, AIX
- * Windows (msvc 2013+, cygwin)
- * macOS (clang 3.5+)
- * Android
+* Linux, FreeBSD, OpenBSD, Solaris, AIX
+* Windows (msvc 2013+, cygwin)
+* macOS (clang 3.5+)
+* Android
 
 ## Package managers:
+* Debian: `sudo apt install libspdlog-dev`
 * Homebrew: `brew install spdlog`
 * MacPorts: `sudo port install spdlog`
-* FreeBSD:  `cd /usr/ports/devel/spdlog/ && make install clean`
-* Fedora: `yum install spdlog`
+* FreeBSD:  `pkg install spdlog`
+* Fedora: `dnf install spdlog`
 * Gentoo: `emerge dev-libs/spdlog`
 * Arch Linux: `pacman -S spdlog`
+* openSUSE: `sudo zypper in spdlog-devel`
+* ALT Linux: `apt-get install libspdlog-devel`
 * vcpkg: `vcpkg install spdlog`
-* conan: `spdlog/[>=1.4.1]`
+* conan: `conan install --requires=spdlog/[*]`
 * conda: `conda install -c conda-forge spdlog`
+* build2: ```depends: spdlog ^1.8.2```
 
 
 ## Features
 * Very fast (see [benchmarks](#benchmarks) below).
 * Headers only or compiled
-* Feature rich formatting, using the excellent [fmt](https://github.com/fmtlib/fmt) library.
+* Feature-rich formatting, using the excellent [fmt](https://github.com/fmtlib/fmt) library.
 * Asynchronous mode (optional)
-* [Custom](https://github.com/gabime/spdlog/wiki/3.-Custom-formatting) formatting.
+* [Custom](https://github.com/gabime/spdlog/wiki/Custom-formatting) formatting.
 * Multi/Single threaded loggers.
 * Various log targets:
-    * Rotating log files.
-    * Daily log files.
-    * Console logging (colors supported).
-    * syslog.
-    * Windows debugger (```OutputDebugString(..)```)
-    * Easily extendable with custom log targets  (just implement a single function in the [sink](include/spdlog/sinks/sink.h) interface).
-* Log filtering - log levels can be modified in runtime as well as in compile time.
-* Support for loading log levels from argv or from environment var.
-* [Backtrace](#backtrace-support) support - store debug messages in a ring buffer and display later on demand.
- 
+  * Rotating log files.
+  * Daily log files.
+  * Console logging (colors supported).
+  * syslog.
+  * Windows event log.
+  * Windows debugger (```OutputDebugString(..)```).
+  * Log to Qt widgets ([example](#log-to-qt-with-nice-colors)).
+  * Easily [extendable](https://github.com/gabime/spdlog/wiki/Sinks#implementing-your-own-sink) with custom log targets.
+* Log filtering - log levels can be modified at runtime as well as compile time.
+* Support for loading log levels from argv or environment var.
+* [Backtrace](#backtrace-support) support - store debug messages in a ring buffer and display them later on demand.
+
 ## Usage samples
 
 #### Basic usage
 ```c++
 #include "spdlog/spdlog.h"
-#include "spdlog/sinks/basic_file_sink.h"
 
 int main() 
 {
@@ -76,13 +87,10 @@ int main()
     spdlog::set_pattern("[%H:%M:%S %z] [%n] [%^---%L---%$] [thread %t] %v");
     
     // Compile time log levels
-    // define SPDLOG_ACTIVE_LEVEL to desired level
+    // Note that this does not change the current log level, it will only
+    // remove (depending on SPDLOG_ACTIVE_LEVEL) the call on the release code.
     SPDLOG_TRACE("Some trace message with param {}", 42);
     SPDLOG_DEBUG("Some debug message");
-    
-    // Set the default logger to file logger
-    auto file_logger = spdlog::basic_logger_mt("basic_logger", "logs/basic.txt");
-    spdlog::set_default_logger(file_logger);            
 }
 
 ```
@@ -93,7 +101,7 @@ int main()
 #include "spdlog/sinks/stdout_color_sinks.h"
 void stdout_example()
 {
-    // create color multi threaded logger
+    // create a color multi-threaded logger
     auto console = spdlog::stdout_color_mt("console");    
     auto err_logger = spdlog::stderr_color_mt("stderr");    
     spdlog::get("console")->info("loggers can be retrieved from a global registry using the spdlog::get(logger_name)");
@@ -122,7 +130,7 @@ void basic_logfile_example()
 #include "spdlog/sinks/rotating_file_sink.h"
 void rotating_example()
 {
-    // Create a file rotating logger with 5mb size max and 3 rotated files
+    // Create a file rotating logger with 5 MB size max and 3 rotated files
     auto max_size = 1048576 * 5;
     auto max_files = 3;
     auto logger = spdlog::rotating_logger_mt("some_logger_name", "logs/rotating.txt", max_size, max_files);
@@ -136,7 +144,7 @@ void rotating_example()
 #include "spdlog/sinks/daily_file_sink.h"
 void daily_example()
 {
-    // Create a daily logger - a new file is created every day on 2:30am
+    // Create a daily logger - a new file is created every day at 2:30 am
     auto logger = spdlog::daily_logger_mt("daily_logger", "logs/daily.txt", 2, 30);
 }
 
@@ -145,10 +153,11 @@ void daily_example()
 ---
 #### Backtrace support
 ```c++
-// Loggers can store in a ring buffer all messages (including debug/trace) and display later on demand.
-// When needed, call dump_backtrace() to see them
+// Debug messages can be stored in a ring buffer instead of being logged immediately.
+// This is useful to display debug logs only when needed (e.g. when an error happens).
+// When needed, call dump_backtrace() to dump them to your log.
 
-spdlog::enable_backtrace(32); // Store the latest 32 messages in a buffer. Older messages will be dropped.
+spdlog::enable_backtrace(32); // Store the latest 32 messages in a buffer. 
 // or my_logger->enable_backtrace(32)..
 for(int i = 0; i < 100; i++)
 {
@@ -156,7 +165,6 @@ for(int i = 0; i < 100; i++)
 }
 // e.g. if some error happened:
 spdlog::dump_backtrace(); // log them now! show the last 32 messages
-
 // or my_logger->dump_backtrace(32)..
 ```
 
@@ -164,11 +172,25 @@ spdlog::dump_backtrace(); // log them now! show the last 32 messages
 #### Periodic flush
 ```c++
 // periodically flush all *registered* loggers every 3 seconds:
-// warning: only use if all your loggers are thread safe ("_mt" loggers)
+// warning: only use if all your loggers are thread-safe ("_mt" loggers)
 spdlog::flush_every(std::chrono::seconds(3));
 
 ```
 
+---
+#### Stopwatch
+```c++
+// Stopwatch support for spdlog
+#include "spdlog/stopwatch.h"
+void stopwatch_example()
+{
+    spdlog::stopwatch sw;    
+    spdlog::debug("Elapsed {}", sw);
+    spdlog::debug("Elapsed {:.3}", sw);       
+}
+
+```
+
 ---
 #### Log binary data in hex
 ```c++
@@ -178,7 +200,8 @@ spdlog::flush_every(std::chrono::seconds(3));
 // {:X} - print in uppercase.
 // {:s} - don't separate each byte with space.
 // {:p} - don't print the position on each line start.
-// {:n} - don't split the output to lines.
+// {:n} - don't split the output into lines.
+// {:a} - show ASCII if :n is not set.
 
 #include "spdlog/fmt/bin_to_hex.h"
 
@@ -197,11 +220,11 @@ void binary_example()
 ```
 
 ---
-#### Logger with multi sinks - each with different format and log level
+#### Logger with multi sinks - each with a different format and log level
 ```c++
 
-// create logger with 2 targets with different log levels and formats.
-// the console will show only warnings or errors, while the file will log all.
+// create a logger with 2 targets, with different log levels and formats.
+// The console will show only warnings or errors, while the file will log all.
 void multi_sink_example()
 {
     auto console_sink = std::make_shared<spdlog::sinks::stdout_color_sink_mt>();
@@ -218,6 +241,27 @@ void multi_sink_example()
 }
 ```
 
+---
+#### User-defined callbacks about log events
+```c++
+
+// create a logger with a lambda function callback, the callback will be called
+// each time something is logged to the logger
+void callback_example()
+{
+    auto callback_sink = std::make_shared<spdlog::sinks::callback_sink_mt>([](const spdlog::details::log_msg &msg) {
+         // for example you can be notified by sending an email to yourself
+    });
+    callback_sink->set_level(spdlog::level::err);
+
+    auto console_sink = std::make_shared<spdlog::sinks::stdout_color_sink_mt>();
+    spdlog::logger logger("custom_callback_logger", {console_sink, callback_sink});
+
+    logger.info("some info log");
+    logger.error("critical issue"); // will notify you
+}
+```
+
 ---
 #### Asynchronous logging
 ```c++
@@ -235,8 +279,9 @@ void async_example()
 ```
 
 ---
-#### Asynchronous logger with multi sinks  
+#### Asynchronous logger with multi sinks
 ```c++
+#include "spdlog/async.h"
 #include "spdlog/sinks/stdout_color_sinks.h"
 #include "spdlog/sinks/rotating_file_sink.h"
 
@@ -252,29 +297,26 @@ void multi_sink_example2()
 ```
  
 ---
-#### User defined types
+#### User-defined types
 ```c++
-// user defined types logging by implementing operator<<
-#include "spdlog/fmt/ostr.h" // must be included
-struct my_type
+template<>
+struct fmt::formatter<my_type> : fmt::formatter<std::string>
 {
-    int i;
-    template<typename OStream>
-    friend OStream &operator<<(OStream &os, const my_type &c)
+    auto format(my_type my, format_context &ctx) const -> decltype(ctx.out())
     {
-        return os << "[my_type i=" << c.i << "]";
+        return fmt::format_to(ctx.out(), "[my_type i={}]", my.i);
     }
 };
 
 void user_defined_example()
 {
-    spdlog::get("console")->info("user defined type: {}", my_type{14});
+    spdlog::info("user defined type: {}", my_type(14));
 }
 
 ```
 
 ---
-#### User defined flags in the log pattern
+#### User-defined flags in the log pattern
 ```c++ 
 // Log patterns can contain custom flags.
 // the following example will add new flag '%*' - which will be bound to a <my_formatter_flag> instance.
@@ -316,7 +358,7 @@ void err_handler_example()
 ```
 
 ---
-#### syslog 
+#### syslog
 ```c++
 #include "spdlog/sinks/syslog_sink.h"
 void syslog_example()
@@ -327,7 +369,7 @@ void syslog_example()
 }
 ```
 ---
-#### Android example 
+#### Android example
 ```c++
 #include "spdlog/sinks/android_sink.h"
 void android_example()
@@ -339,14 +381,17 @@ void android_example()
 ```
 
 ---
-#### Load log levels from env variable or from argv
+#### Load log levels from the env variable or argv
 
 ```c++
 #include "spdlog/cfg/env.h"
 int main (int argc, char *argv[])
 {
     spdlog::cfg::load_env_levels();
-    // or from command line:
+    // or specify the env variable name:
+    // MYAPP_LEVEL=info,mylogger=trace && ./example
+    // spdlog::cfg::load_env_levels("MYAPP_LEVEL");
+    // or from the command line:
     // ./example SPDLOG_LEVEL=info,mylogger=trace
     // #include "spdlog/cfg/argv.h" // for loading levels from argv
     // spdlog::cfg::load_argv_levels(argc, argv);
@@ -359,10 +404,70 @@ $ export SPDLOG_LEVEL=info,mylogger=trace
 $ ./example
 ```
 
+
+---
+#### Log file open/close event handlers
+```c++
+// You can get callbacks from spdlog before/after a log file has been opened or closed. 
+// This is useful for cleanup procedures or for adding something to the start/end of the log file.
+void file_events_example()
+{
+    // pass the spdlog::file_event_handlers to file sinks for open/close log file notifications
+    spdlog::file_event_handlers handlers;
+    handlers.before_open = [](spdlog::filename_t filename) { spdlog::info("Before opening {}", filename); };
+    handlers.after_open = [](spdlog::filename_t filename, std::FILE *fstream) { fputs("After opening\n", fstream); };
+    handlers.before_close = [](spdlog::filename_t filename, std::FILE *fstream) { fputs("Before closing\n", fstream); };
+    handlers.after_close = [](spdlog::filename_t filename) { spdlog::info("After closing {}", filename); };
+    auto my_logger = spdlog::basic_logger_st("some_logger", "logs/events-sample.txt", true, handlers);        
+}
+```
+
+---
+#### Replace the Default Logger
+```c++
+void replace_default_logger_example()
+{
+    auto new_logger = spdlog::basic_logger_mt("new_default_logger", "logs/new-default-log.txt", true);
+    spdlog::set_default_logger(new_logger);
+    spdlog::info("new logger log message");
+}
+```
+
+---
+#### Log to Qt with nice colors
+```c++
+#include "spdlog/spdlog.h"
+#include "spdlog/sinks/qt_sinks.h"
+MainWindow::MainWindow(QWidget *parent) : QMainWindow(parent)
+{
+    setMinimumSize(640, 480);
+    auto log_widget = new QTextEdit(this);
+    setCentralWidget(log_widget);
+    int max_lines = 500; // keep the text widget to max 500 lines. remove old lines if needed.
+    auto logger = spdlog::qt_color_logger_mt("qt_logger", log_widget, max_lines);
+    logger->info("Some info message");
+}
+```
+---
+
+#### Mapped Diagnostic Context
+```c++
+// Mapped Diagnostic Context (MDC) is a map that stores key-value pairs (string values) in thread local storage.
+// Each thread maintains its own MDC, which loggers use to append diagnostic information to log outputs.
+// Note: it is not supported in asynchronous mode due to its reliance on thread-local storage.
+#include "spdlog/mdc.h"
+void mdc_example()
+{
+    spdlog::mdc::put("key1", "value1");
+    spdlog::mdc::put("key2", "value2");
+    // if not using the default format, use the %& formatter to print mdc data
+    // spdlog::set_pattern("[%H:%M:%S %z] [%^%L%$] [%&] %v");
+}
+```
 ---
 ## Benchmarks
 
-Below are some [benchmarks](https://github.com/gabime/spdlog/blob/v1.x/bench/bench.cpp) done in Ubuntu 64 bit, Intel i7-4770 CPU @ 3.40GHz
+Below are some [benchmarks](bench/bench.cpp) done in Ubuntu 64 bit, Intel i7-4770 CPU @ 3.40GHz
 
 #### Synchronous mode
 ```
@@ -414,10 +519,12 @@ Below are some [benchmarks](https://github.com/gabime/spdlog/blob/v1.x/bench/ben
 ```
 
 ## Documentation
-Documentation can be found in the [wiki](https://github.com/gabime/spdlog/wiki/1.-QuickStart) pages.
+
+Documentation can be found in the [wiki](https://github.com/gabime/spdlog/wiki) pages.
 
 ---
 
-Thanks to [JetBrains](https://www.jetbrains.com/?from=spdlog) for donating licenses to their products to help developing **spdlog** <a href="https://www.jetbrains.com/?from=spdlog"><img src="logos/jetbrains-variant-4.svg" width="94" align="center" /></a>
-
-
+### Powered by
+<a href="https://jb.gg/OpenSource">
+  <img src="https://resources.jetbrains.com/storage/products/company/brand/logos/jetbrains.svg" alt="JetBrains logo" width="200">
+</a>

appveyor.yml

@@ -2,34 +2,72 @@ version: 1.0.{build}
 image: Visual Studio 2017
 environment:
   matrix:
-    - GENERATOR: '"Visual Studio 14 2015"'
-      BUILD_TYPE: Debug
-      WCHAR: 'OFF'
-      BUILD_SHARED: 'OFF'
-    - GENERATOR: '"Visual Studio 14 2015"'
-      BUILD_TYPE: Release
-      WCHAR: 'ON'
-      BUILD_SHARED: 'OFF'
-    - GENERATOR: '"Visual Studio 14 2015 Win64"'
-      BUILD_TYPE: Debug
-      WCHAR: 'ON'
-      BUILD_SHARED: 'OFF'
-    - GENERATOR: '"Visual Studio 14 2015 Win64"'
-      BUILD_TYPE: Release
-      WCHAR: 'ON'
-      BUILD_SHARED: 'OFF'
     - GENERATOR: '"Visual Studio 15 2017 Win64"'
       BUILD_TYPE: Debug
+      BUILD_SHARED: 'OFF'
+      FATAL_ERRORS: 'OFF'
       WCHAR: 'ON'
-      BUILD_SHARED: 'OFF'
+      WCHAR_FILES: 'OFF'
+      BUILD_EXAMPLE: 'ON'
+      USE_STD_FORMAT: 'OFF'
+      CXX_STANDARD: 11
     - GENERATOR: '"Visual Studio 15 2017 Win64"'
       BUILD_TYPE: Release
-      WCHAR: 'OFF'
       BUILD_SHARED: 'OFF'
+      FATAL_ERRORS: 'OFF'
+      WCHAR: 'OFF'
+      WCHAR_FILES: 'OFF'
+      BUILD_EXAMPLE: 'ON'
+      USE_STD_FORMAT: 'OFF'
+      CXX_STANDARD: 11
     - GENERATOR: '"Visual Studio 15 2017 Win64"'
       BUILD_TYPE: Release
-      WCHAR: 'OFF'
       BUILD_SHARED: 'ON'
+      FATAL_ERRORS: 'OFF'
+      WCHAR: 'OFF'
+      WCHAR_FILES: 'OFF'
+      BUILD_EXAMPLE: 'ON'
+      USE_STD_FORMAT: 'OFF'
+      CXX_STANDARD: 11
+    - GENERATOR: '"Visual Studio 15 2017 Win64"'
+      BUILD_TYPE: Release
+      BUILD_SHARED: 'ON'
+      FATAL_ERRORS: 'OFF'
+      WCHAR: 'ON'
+      WCHAR_FILES: 'ON'
+      BUILD_EXAMPLE: 'OFF'
+      USE_STD_FORMAT: 'OFF'
+      CXX_STANDARD: 11
+    - GENERATOR: '"Visual Studio 16 2019" -A x64'
+      BUILD_TYPE: Release
+      BUILD_SHARED: 'ON'
+      FATAL_ERRORS: 'ON'
+      WCHAR: 'OFF'
+      WCHAR_FILES: 'OFF'
+      BUILD_EXAMPLE: 'OFF'
+      USE_STD_FORMAT: 'OFF'
+      CXX_STANDARD: 17
+      APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2019
+    - GENERATOR: '"Visual Studio 17 2022" -A x64'
+      BUILD_TYPE: Release
+      BUILD_SHARED: 'ON'
+      FATAL_ERRORS: 'ON'
+      WCHAR: 'OFF'
+      WCHAR_FILES: 'OFF'
+      BUILD_EXAMPLE: 'OFF'
+      USE_STD_FORMAT: 'ON'
+      CXX_STANDARD: 20
+      APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2022
+    - GENERATOR: '"Visual Studio 17 2022" -A x64'
+      BUILD_TYPE: Release
+      BUILD_SHARED: 'ON'
+      FATAL_ERRORS: 'ON'
+      WCHAR: 'ON'
+      WCHAR_FILES: 'ON'
+      BUILD_EXAMPLE: 'OFF'
+      USE_STD_FORMAT: 'ON'
+      CXX_STANDARD: 20
+      APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2022
 build_script:
   - cmd: >-
       set
@@ -40,12 +78,12 @@ build_script:
 
       set PATH=%PATH%;C:\Program Files\Git\usr\bin
 
-      cmake .. -G %GENERATOR% -DCMAKE_BUILD_TYPE=%BUILD_TYPE% -DSPDLOG_WCHAR_SUPPORT=%WCHAR% -DSPDLOG_BUILD_SHARED=%BUILD_SHARED% -DSPDLOG_BUILD_EXAMPLE=ON -DSPDLOG_BUILD_EXAMPLE_HO=ON -DSPDLOG_BUILD_TESTS=ON -DSPDLOG_BUILD_TESTS_HO=OFF -DSPDLOG_ENABLE_WARNINGS=ON
+      cmake -G %GENERATOR% -D CMAKE_BUILD_TYPE=%BUILD_TYPE% -D BUILD_SHARED_LIBS=%BUILD_SHARED% -D SPDLOG_WCHAR_SUPPORT=%WCHAR% -D SPDLOG_WCHAR_FILENAMES=%WCHAR_FILES% -D SPDLOG_BUILD_EXAMPLE=%BUILD_EXAMPLE% -D SPDLOG_BUILD_EXAMPLE_HO=%BUILD_EXAMPLE% -D SPDLOG_BUILD_TESTS=ON -D SPDLOG_BUILD_TESTS_HO=OFF -D SPDLOG_BUILD_WARNINGS=%FATAL_ERRORS% -D SPDLOG_USE_STD_FORMAT=%USE_STD_FORMAT% -D CMAKE_CXX_STANDARD=%CXX_STANDARD% ..
 
       cmake --build . --config %BUILD_TYPE%
 
 before_test:
-  - set PATH=%PATH%;C:\projects\spdlog\build\%BUILD_TYPE%
+  - set PATH=%PATH%;C:\projects\spdlog\build\_deps\catch2-build\src\%BUILD_TYPE%;C:\projects\spdlog\build\%BUILD_TYPE%
   
 test_script:
   - C:\projects\spdlog\build\tests\%BUILD_TYPE%\spdlog-utests.exe

bench/CMakeLists.txt

@@ -1,6 +1,6 @@
 # Copyright(c) 2019 spdlog authors Distributed under the MIT License (http://opensource.org/licenses/MIT)
 
-cmake_minimum_required(VERSION 3.1)
+cmake_minimum_required(VERSION 3.11)
 project(spdlog_bench CXX)
 
 if(NOT TARGET spdlog)
@@ -9,7 +9,19 @@ if(NOT TARGET spdlog)
 endif()
 
 find_package(Threads REQUIRED)
-find_package(benchmark CONFIG REQUIRED)
+find_package(benchmark CONFIG)
+if(NOT benchmark_FOUND)
+    message(STATUS "Using CMake Version ${CMAKE_VERSION}")
+    # User can fetch googlebenchmark
+    message(STATUS "Downloading GoogleBenchmark")
+    include(FetchContent)
+
+    # disable tests
+    set(BENCHMARK_ENABLE_TESTING OFF CACHE INTERNAL "")
+    # Do not build and run googlebenchmark tests
+    FetchContent_Declare(googlebenchmark GIT_REPOSITORY https://github.com/google/benchmark.git GIT_TAG v1.6.0)
+    FetchContent_MakeAvailable(googlebenchmark)
+endif()
 
 add_executable(bench bench.cpp)
 spdlog_enable_warnings(bench)

bench/async_bench.cpp

@@ -9,7 +9,14 @@
 #include "spdlog/spdlog.h"
 #include "spdlog/async.h"
 #include "spdlog/sinks/basic_file_sink.h"
-#include "spdlog/sinks/stdout_color_sinks.h"
+
+#if defined(SPDLOG_USE_STD_FORMAT)
+    #include <format>
+#elif defined(SPDLOG_FMT_EXTERNAL)
+    #include <fmt/format.h>
+#else
+    #include "spdlog/fmt/bundled/format.h"
+#endif
 
 #include "utils.h"
 #include <atomic>
@@ -27,82 +34,70 @@ using namespace utils;
 void bench_mt(int howmany, std::shared_ptr<spdlog::logger> log, int thread_count);
 
 #ifdef _MSC_VER
-#pragma warning(push)
-#pragma warning(disable : 4996) // disable fopen warning under msvc
-#endif                          // _MSC_VER
+    #pragma warning(push)
+    #pragma warning(disable : 4996)  // disable fopen warning under msvc
+#endif                               // _MSC_VER
 
-int count_lines(const char *filename)
-{
+int count_lines(const char *filename) {
     int counter = 0;
     auto *infile = fopen(filename, "r");
     int ch;
-    while (EOF != (ch = getc(infile)))
-    {
-        if ('\n' == ch)
-            counter++;
+    while (EOF != (ch = getc(infile))) {
+        if ('\n' == ch) counter++;
     }
     fclose(infile);
 
     return counter;
 }
 
-void verify_file(const char *filename, int expected_count)
-{
-    spdlog::info("Verifying {} to contain {:n} line..", filename, expected_count);
+void verify_file(const char *filename, int expected_count) {
+    spdlog::info("Verifying {} to contain {} line..", filename, expected_count);
     auto count = count_lines(filename);
-    if (count != expected_count)
-    {
-        spdlog::error("Test failed. {} has {:n} lines instead of {:n}", filename, count, expected_count);
+    if (count != expected_count) {
+        spdlog::error("Test failed. {} has {} lines instead of {}", filename, count,
+                      expected_count);
         exit(1);
     }
-    spdlog::info("Line count OK ({:n})\n", count);
+    spdlog::info("Line count OK ({})\n", count);
 }
 
 #ifdef _MSC_VER
-#pragma warning(pop)
+    #pragma warning(pop)
 #endif
 
-int main(int argc, char *argv[])
-{
-
+int main(int argc, char *argv[]) {
     int howmany = 1000000;
     int queue_size = std::min(howmany + 2, 8192);
     int threads = 10;
     int iters = 3;
 
-    try
-    {
+    try {
         spdlog::set_pattern("[%^%l%$] %v");
-        if (argc == 1)
-        {
+        if (argc == 1) {
             spdlog::info("Usage: {} <message_count> <threads> <q_size> <iterations>", argv[0]);
             return 0;
         }
 
-        if (argc > 1)
-            howmany = atoi(argv[1]);
-        if (argc > 2)
-            threads = atoi(argv[2]);
-        if (argc > 3)
-        {
+        if (argc > 1) howmany = atoi(argv[1]);
+        if (argc > 2) threads = atoi(argv[2]);
+        if (argc > 3) {
             queue_size = atoi(argv[3]);
-            if (queue_size > 500000)
-            {
+            if (queue_size > 500000) {
                 spdlog::error("Max queue size allowed: 500,000");
                 exit(1);
             }
         }
 
-        if (argc > 4)
-            iters = atoi(argv[4]);
+        if (argc > 4) iters = atoi(argv[4]);
 
         auto slot_size = sizeof(spdlog::details::async_msg);
         spdlog::info("-------------------------------------------------");
-        spdlog::info("Messages     : {:n}", howmany);
-        spdlog::info("Threads      : {:n}", threads);
-        spdlog::info("Queue        : {:n} slots", queue_size);
-        spdlog::info("Queue memory : {:n} x {} = {:n} KB ", queue_size, slot_size, (queue_size * slot_size) / 1024);
-        spdlog::info("Total iters  : {:n}", iters);
+        spdlog::info("Messages     : {:L}", howmany);
+        spdlog::info("Threads      : {:L}", threads);
+        spdlog::info("Queue        : {:L} slots", queue_size);
+        spdlog::info("Queue memory : {:L} x {:L} = {:L} KB ", queue_size, slot_size,
+                     (queue_size * slot_size) / 1024);
+        spdlog::info("Total iters  : {:L}", iters);
         spdlog::info("-------------------------------------------------");
 
         const char *filename = "logs/basic_async.log";
@@ -110,11 +105,11 @@ int main(int argc, char *argv[])
         spdlog::info("*********************************");
         spdlog::info("Queue Overflow Policy: block");
         spdlog::info("*********************************");
-        for (int i = 0; i < iters; i++)
-        {
+        for (int i = 0; i < iters; i++) {
             auto tp = std::make_shared<details::thread_pool>(queue_size, 1);
             auto file_sink = std::make_shared<spdlog::sinks::basic_file_sink_mt>(filename, true);
-            auto logger = std::make_shared<async_logger>("async_logger", std::move(file_sink), std::move(tp), async_overflow_policy::block);
+            auto logger = std::make_shared<async_logger>(
+                "async_logger", std::move(file_sink), std::move(tp), async_overflow_policy::block);
             bench_mt(howmany, std::move(logger), threads);
             // verify_file(filename, howmany);
         }
@@ -125,18 +120,16 @@ int main(int argc, char *argv[])
         spdlog::info("*********************************");
         // do same test but discard oldest if queue is full instead of blocking
         filename = "logs/basic_async-overrun.log";
-        for (int i = 0; i < iters; i++)
-        {
+        for (int i = 0; i < iters; i++) {
             auto tp = std::make_shared<details::thread_pool>(queue_size, 1);
             auto file_sink = std::make_shared<spdlog::sinks::basic_file_sink_mt>(filename, true);
             auto logger =
-                std::make_shared<async_logger>("async_logger", std::move(file_sink), std::move(tp), async_overflow_policy::overrun_oldest);
+                std::make_shared<async_logger>("async_logger", std::move(file_sink), std::move(tp),
+                                               async_overflow_policy::overrun_oldest);
             bench_mt(howmany, std::move(logger), threads);
         }
         spdlog::shutdown();
-    }
-    catch (std::exception &ex)
-    {
+    } catch (std::exception &ex) {
         std::cerr << "Error: " << ex.what() << std::endl;
         perror("Last error");
         return 1;
@@ -144,36 +137,32 @@ int main(int argc, char *argv[])
     return 0;
 }
 
-void thread_fun(std::shared_ptr<spdlog::logger> logger, int howmany)
-{
-    for (int i = 0; i < howmany; i++)
-    {
+void thread_fun(std::shared_ptr<spdlog::logger> logger, int howmany) {
+    for (int i = 0; i < howmany; i++) {
         logger->info("Hello logger: msg number {}", i);
     }
 }
 
-void bench_mt(int howmany, std::shared_ptr<spdlog::logger> logger, int thread_count)
-{
+void bench_mt(int howmany, std::shared_ptr<spdlog::logger> logger, int thread_count) {
     using std::chrono::high_resolution_clock;
-    vector<thread> threads;
+    vector<std::thread> threads;
     auto start = high_resolution_clock::now();
 
     int msgs_per_thread = howmany / thread_count;
     int msgs_per_thread_mod = howmany % thread_count;
-    for (int t = 0; t < thread_count; ++t)
-    {
+    for (int t = 0; t < thread_count; ++t) {
         if (t == 0 && msgs_per_thread_mod)
-            threads.push_back(std::thread(thread_fun, logger, msgs_per_thread + msgs_per_thread_mod));
+            threads.push_back(
+                std::thread(thread_fun, logger, msgs_per_thread + msgs_per_thread_mod));
         else
             threads.push_back(std::thread(thread_fun, logger, msgs_per_thread));
     }
 
-    for (auto &t : threads)
-    {
+    for (auto &t : threads) {
         t.join();
-    };
+    }
 
     auto delta = high_resolution_clock::now() - start;
     auto delta_d = duration_cast<duration<double>>(delta).count();
-    spdlog::info("Elapsed: {} secs\t {:n}/sec", delta_d, int(howmany / delta_d));
+    spdlog::info("Elapsed: {} secs\t {:L}/sec", delta_d, int(howmany / delta_d));
 }

bench/bench.cpp

@@ -12,9 +12,17 @@
 #include "spdlog/sinks/null_sink.h"
 #include "spdlog/sinks/rotating_file_sink.h"
 
+#if defined(SPDLOG_USE_STD_FORMAT)
+    #include <format>
+#elif defined(SPDLOG_FMT_EXTERNAL)
+    #include <fmt/format.h>
+#else
+    #include "spdlog/fmt/bundled/format.h"
+#endif
+
 #include "utils.h"
 #include <atomic>
-#include <cstdlib> // EXIT_FAILURE
+#include <cstdlib>  // EXIT_FAILURE
 #include <memory>
 #include <string>
 #include <thread>
@@ -29,22 +37,25 @@ static const size_t file_size = 30 * 1024 * 1024;
 static const size_t rotating_files = 5;
 static const int max_threads = 1000;
 
-void bench_threaded_logging(size_t threads, int iters)
-{
+void bench_threaded_logging(size_t threads, int iters) {
     spdlog::info("**************************************************************");
-    spdlog::info("Multi threaded: {:n} threads, {:n} messages", threads, iters);
+    spdlog::info(spdlog::fmt_lib::format(
+        std::locale("en_US.UTF-8"), "Multi threaded: {:L} threads, {:L} messages", threads, iters));
     spdlog::info("**************************************************************");
 
     auto basic_mt = spdlog::basic_logger_mt("basic_mt", "logs/basic_mt.log", true);
     bench_mt(iters, std::move(basic_mt), threads);
-    auto basic_mt_tracing = spdlog::basic_logger_mt("basic_mt/backtrace-on", "logs/basic_mt.log", true);
+    auto basic_mt_tracing =
+        spdlog::basic_logger_mt("basic_mt/backtrace-on", "logs/basic_mt.log", true);
     basic_mt_tracing->enable_backtrace(32);
     bench_mt(iters, std::move(basic_mt_tracing), threads);
 
     spdlog::info("");
-    auto rotating_mt = spdlog::rotating_logger_mt("rotating_mt", "logs/rotating_mt.log", file_size, rotating_files);
+    auto rotating_mt = spdlog::rotating_logger_mt("rotating_mt", "logs/rotating_mt.log", file_size,
+                                                  rotating_files);
     bench_mt(iters, std::move(rotating_mt), threads);
-    auto rotating_mt_tracing = spdlog::rotating_logger_mt("rotating_mt/backtrace-on", "logs/rotating_mt.log", file_size, rotating_files);
+    auto rotating_mt_tracing = spdlog::rotating_logger_mt(
+        "rotating_mt/backtrace-on", "logs/rotating_mt.log", file_size, rotating_files);
     rotating_mt_tracing->enable_backtrace(32);
     bench_mt(iters, std::move(rotating_mt_tracing), threads);
 
@@ -65,22 +76,25 @@ void bench_threaded_logging(size_t threads, int iters)
     bench(iters, empty_logger_tracing);
 }
 
-void bench_single_threaded(int iters)
-{
+void bench_single_threaded(int iters) {
     spdlog::info("**************************************************************");
-    spdlog::info("Single threaded: {:n} messages", iters);
+    spdlog::info(
+        spdlog::fmt_lib::format(std::locale("en_US.UTF-8"), "Single threaded: {} messages", iters));
     spdlog::info("**************************************************************");
 
     auto basic_st = spdlog::basic_logger_st("basic_st", "logs/basic_st.log", true);
     bench(iters, std::move(basic_st));
 
-    auto basic_st_tracing = spdlog::basic_logger_st("basic_st/backtrace-on", "logs/basic_st.log", true);
+    auto basic_st_tracing =
+        spdlog::basic_logger_st("basic_st/backtrace-on", "logs/basic_st.log", true);
     bench(iters, std::move(basic_st_tracing));
 
     spdlog::info("");
-    auto rotating_st = spdlog::rotating_logger_st("rotating_st", "logs/rotating_st.log", file_size, rotating_files);
+    auto rotating_st = spdlog::rotating_logger_st("rotating_st", "logs/rotating_st.log", file_size,
+                                                  rotating_files);
     bench(iters, std::move(rotating_st));
-    auto rotating_st_tracing = spdlog::rotating_logger_st("rotating_st/backtrace-on", "logs/rotating_st.log", file_size, rotating_files);
+    auto rotating_st_tracing = spdlog::rotating_logger_st(
+        "rotating_st/backtrace-on", "logs/rotating_st.log", file_size, rotating_files);
     rotating_st_tracing->enable_backtrace(32);
     bench(iters, std::move(rotating_st_tracing));
 
@@ -102,62 +116,54 @@ void bench_single_threaded(int iters)
     bench(iters, empty_logger_tracing);
 }
 
-int main(int argc, char *argv[])
-{
+int main(int argc, char *argv[]) {
     spdlog::set_automatic_registration(false);
     spdlog::default_logger()->set_pattern("[%^%l%$] %v");
     int iters = 250000;
     size_t threads = 4;
-    try
-    {
-
-        if (argc > 1)
-        {
+    try {
+        if (argc > 1) {
             iters = std::stoi(argv[1]);
         }
-        if (argc > 2)
-        {
+        if (argc > 2) {
             threads = std::stoul(argv[2]);
         }
 
-        if (threads > max_threads)
-        {
-            throw std::runtime_error(fmt::format("Number of threads exceeds maximum({}})", max_threads));
+        if (threads > max_threads) {
+            throw std::runtime_error(
+                spdlog::fmt_lib::format("Number of threads exceeds maximum({})", max_threads));
         }
 
         bench_single_threaded(iters);
         bench_threaded_logging(1, iters);
         bench_threaded_logging(threads, iters);
-    }
-    catch (std::exception &ex)
-    {
+    } catch (std::exception &ex) {
         spdlog::error(ex.what());
         return EXIT_FAILURE;
     }
     return EXIT_SUCCESS;
 }
 
-void bench(int howmany, std::shared_ptr<spdlog::logger> log)
-{
+void bench(int howmany, std::shared_ptr<spdlog::logger> log) {
     using std::chrono::duration;
     using std::chrono::duration_cast;
     using std::chrono::high_resolution_clock;
 
     auto start = high_resolution_clock::now();
-    for (auto i = 0; i < howmany; ++i)
-    {
+    for (auto i = 0; i < howmany; ++i) {
         log->info("Hello logger: msg number {}", i);
     }
 
     auto delta = high_resolution_clock::now() - start;
     auto delta_d = duration_cast<duration<double>>(delta).count();
 
-    spdlog::info("{:<30} Elapsed: {:0.2f} secs {:>16n}/sec", log->name(), delta_d, int(howmany / delta_d));
+    spdlog::info(spdlog::fmt_lib::format(std::locale("en_US.UTF-8"),
+                                         "{:<30} Elapsed: {:0.2f} secs {:>16L}/sec", log->name(),
+                                         delta_d, size_t(howmany / delta_d)));
     spdlog::drop(log->name());
 }
 
-void bench_mt(int howmany, std::shared_ptr<spdlog::logger> log, size_t thread_count)
-{
+void bench_mt(int howmany, std::shared_ptr<spdlog::logger> log, size_t thread_count) {
     using std::chrono::duration;
     using std::chrono::duration_cast;
     using std::chrono::high_resolution_clock;
@@ -165,24 +171,23 @@ void bench_mt(int howmany, std::shared_ptr<spdlog::logger> log, size_t thread_co
     std::vector<std::thread> threads;
     threads.reserve(thread_count);
     auto start = high_resolution_clock::now();
-    for (size_t t = 0; t < thread_count; ++t)
-    {
+    for (size_t t = 0; t < thread_count; ++t) {
         threads.emplace_back([&]() {
-            for (int j = 0; j < howmany / static_cast<int>(thread_count); j++)
-            {
+            for (int j = 0; j < howmany / static_cast<int>(thread_count); j++) {
                 log->info("Hello logger: msg number {}", j);
             }
         });
     }
 
-    for (auto &t : threads)
-    {
+    for (auto &t : threads) {
         t.join();
-    };
+    }
 
     auto delta = high_resolution_clock::now() - start;
     auto delta_d = duration_cast<duration<double>>(delta).count();
-    spdlog::info("{:<30} Elapsed: {:0.2f} secs {:>16n}/sec", log->name(), delta_d, int(howmany / delta_d));
+    spdlog::info(spdlog::fmt_lib::format(std::locale("en_US.UTF-8"),
+                                         "{:<30} Elapsed: {:0.2f} secs {:>16L}/sec", log->name(),
+                                         delta_d, size_t(howmany / delta_d)));
     spdlog::drop(log->name());
 }
 
@@ -205,7 +210,8 @@ void bench_default_api(int howmany, std::shared_ptr<spdlog::logger> log)
     auto delta_d = duration_cast<duration<double>>(delta).count();
     spdlog::drop(log->name());
     spdlog::set_default_logger(std::move(orig_default));
-    spdlog::info("{:<30} Elapsed: {:0.2f} secs {:>16n}/sec", log->name(), delta_d, int(howmany / delta_d));
+    spdlog::info("{:<30} Elapsed: {:0.2f} secs {:>16}/sec", log->name(), delta_d, int(howmany /
+delta_d));
 }
 
 void bench_c_string(int howmany, std::shared_ptr<spdlog::logger> log)
@@ -214,11 +220,12 @@ void bench_c_string(int howmany, std::shared_ptr<spdlog::logger> log)
     using std::chrono::duration;
     using std::chrono::duration_cast;
 
-    const char *msg = "Lorem ipsum dolor sit amet, consectetur adipiscing elit. Vestibulum pharetra metus cursus "
-                      "lacus placerat congue. Nulla egestas, mauris a tincidunt tempus, enim lectus volutpat mi, eu consequat sem "
-                      "libero nec massa. In dapibus ipsum a diam rhoncus gravida. Etiam non dapibus eros. Donec fringilla dui sed "
-                      "augue pretium, nec scelerisque est maximus. Nullam convallis, sem nec blandit maximus, nisi turpis ornare "
-                      "nisl, sit amet volutpat neque massa eu odio. Maecenas malesuada quam ex, posuere congue nibh turpis duis.";
+    const char *msg = "Lorem ipsum dolor sit amet, consectetur adipiscing elit. Vestibulum pharetra
+metus cursus " "lacus placerat congue. Nulla egestas, mauris a tincidunt tempus, enim lectus
+volutpat mi, eu consequat sem " "libero nec massa. In dapibus ipsum a diam rhoncus gravida. Etiam
+non dapibus eros. Donec fringilla dui sed " "augue pretium, nec scelerisque est maximus. Nullam
+convallis, sem nec blandit maximus, nisi turpis ornare " "nisl, sit amet volutpat neque massa eu
+odio. Maecenas malesuada quam ex, posuere congue nibh turpis duis.";
 
     auto orig_default = spdlog::default_logger();
     spdlog::set_default_logger(log);
@@ -232,7 +239,8 @@ void bench_c_string(int howmany, std::shared_ptr<spdlog::logger> log)
     auto delta_d = duration_cast<duration<double>>(delta).count();
     spdlog::drop(log->name());
     spdlog::set_default_logger(std::move(orig_default));
-    spdlog::info("{:<30} Elapsed: {:0.2f} secs {:>16n}/sec", log->name(), delta_d, int(howmany / delta_d));
+    spdlog::info("{:<30} Elapsed: {:0.2f} secs {:>16}/sec", log->name(), delta_d, int(howmany /
+delta_d));
 }
 
-*/
+*/

bench/formatter-bench.cpp

@@ -8,40 +8,37 @@
 #include "spdlog/spdlog.h"
 #include "spdlog/pattern_formatter.h"
 
-void bench_formatter(benchmark::State &state, std::string pattern)
-{
+void bench_formatter(benchmark::State &state, std::string pattern) {
     auto formatter = spdlog::details::make_unique<spdlog::pattern_formatter>(pattern);
     spdlog::memory_buf_t dest;
     std::string logger_name = "logger-name";
-    const char *text = "Hello. This is some message with length of 80                                   ";
+    const char *text =
+        "Hello. This is some message with length of 80                                   ";
 
     spdlog::source_loc source_loc{"a/b/c/d/myfile.cpp", 123, "some_func()"};
     spdlog::details::log_msg msg(source_loc, logger_name, spdlog::level::info, text);
 
-    for (auto _ : state)
-    {
+    for (auto _ : state) {
         dest.clear();
         formatter->format(msg, dest);
         benchmark::DoNotOptimize(dest);
     }
 }
 
-void bench_formatters()
-{
+void bench_formatters() {
     // basic patterns(single flag)
     std::string all_flags = "+vtPnlLaAbBcCYDmdHIMSefFprRTXzEisg@luioO%";
     std::vector<std::string> basic_patterns;
-    for (auto &flag : all_flags)
-    {
+    for (auto &flag : all_flags) {
         auto pattern = std::string("%") + flag;
-        benchmark::RegisterBenchmark(pattern.c_str(), bench_formatter, pattern);
+        benchmark::RegisterBenchmark(pattern.c_str(), &bench_formatter, pattern);
 
         //        pattern = std::string("%16") + flag;
-        //        benchmark::RegisterBenchmark(pattern.c_str(), bench_formatter, pattern);
+        //        benchmark::RegisterBenchmark(pattern.c_str(), &bench_formatter, pattern);
         //
         //        // bench center padding
         //        pattern = std::string("%=16") + flag;
-        //        benchmark::RegisterBenchmark(pattern.c_str(), bench_formatter, pattern);
+        //        benchmark::RegisterBenchmark(pattern.c_str(), &bench_formatter, pattern);
     }
 
     // complex patterns
@@ -50,30 +47,24 @@ void bench_formatters()
         "[%Y-%m-%d %H:%M:%S.%e] [%l] [%n] %v",
         "[%Y-%m-%d %H:%M:%S.%e] [%l] [%n] [%t] %v",
     };
-    for (auto &pattern : patterns)
-    {
-        benchmark::RegisterBenchmark(pattern.c_str(), bench_formatter, pattern)->Iterations(2500000);
+    for (auto &pattern : patterns) {
+        benchmark::RegisterBenchmark(pattern.c_str(), &bench_formatter, pattern)
+            ->Iterations(2500000);
     }
 }
 
-int main(int argc, char *argv[])
-{
-
+int main(int argc, char *argv[]) {
     spdlog::set_pattern("[%^%l%$] %v");
-    if (argc != 2)
-    {
+    if (argc != 2) {
         spdlog::error("Usage: {} <pattern> (or \"all\" to bench all)", argv[0]);
         exit(1);
     }
 
     std::string pattern = argv[1];
-    if (pattern == "all")
-    {
+    if (pattern == "all") {
         bench_formatters();
-    }
-    else
-    {
-        benchmark::RegisterBenchmark(pattern.c_str(), bench_formatter, pattern);
+    } else {
+        benchmark::RegisterBenchmark(pattern.c_str(), &bench_formatter, pattern);
     }
     benchmark::Initialize(&argc, argv);
     benchmark::RunSpecifiedBenchmarks();

bench/latency.cpp

@@ -16,56 +16,72 @@
 #include "spdlog/sinks/null_sink.h"
 #include "spdlog/sinks/rotating_file_sink.h"
 
-void bench_c_string(benchmark::State &state, std::shared_ptr<spdlog::logger> logger)
-{
-    const char *msg = "Lorem ipsum dolor sit amet, consectetur adipiscing elit. Vestibulum pharetra metus cursus "
-                      "lacus placerat congue. Nulla egestas, mauris a tincidunt tempus, enim lectus volutpat mi, eu consequat sem "
-                      "libero nec massa. In dapibus ipsum a diam rhoncus gravida. Etiam non dapibus eros. Donec fringilla dui sed "
-                      "augue pretium, nec scelerisque est maximus. Nullam convallis, sem nec blandit maximus, nisi turpis ornare "
-                      "nisl, sit amet volutpat neque massa eu odio. Maecenas malesuada quam ex, posuere congue nibh turpis duis.";
+void bench_c_string(benchmark::State &state, std::shared_ptr<spdlog::logger> logger) {
+    const char *msg =
+        "Lorem ipsum dolor sit amet, consectetur adipiscing elit. Vestibulum pharetra metus cursus "
+        "lacus placerat congue. Nulla egestas, mauris a tincidunt tempus, enim lectus volutpat mi, "
+        "eu consequat sem "
+        "libero nec massa. In dapibus ipsum a diam rhoncus gravida. Etiam non dapibus eros. Donec "
+        "fringilla dui sed "
+        "augue pretium, nec scelerisque est maximus. Nullam convallis, sem nec blandit maximus, "
+        "nisi turpis ornare "
+        "nisl, sit amet volutpat neque massa eu odio. Maecenas malesuada quam ex, posuere congue "
+        "nibh turpis duis.";
 
-    for (auto _ : state)
-    {
+    for (auto _ : state) {
         logger->info(msg);
     }
 }
 
-void bench_logger(benchmark::State &state, std::shared_ptr<spdlog::logger> logger)
-{
+void bench_logger(benchmark::State &state, std::shared_ptr<spdlog::logger> logger) {
     int i = 0;
-    for (auto _ : state)
-    {
+    for (auto _ : state) {
         logger->info("Hello logger: msg number {}...............", ++i);
     }
 }
-
-void bench_disabled_macro(benchmark::State &state, std::shared_ptr<spdlog::logger> logger)
-{
+void bench_global_logger(benchmark::State &state, std::shared_ptr<spdlog::logger> logger) {
+    spdlog::set_default_logger(std::move(logger));
     int i = 0;
-    benchmark::DoNotOptimize(i);      // prevent unused warnings
-    benchmark::DoNotOptimize(logger); // prevent unused warnings
-    for (auto _ : state)
-    {
+    for (auto _ : state) {
+        spdlog::info("Hello logger: msg number {}...............", ++i);
+    }
+}
+
+void bench_disabled_macro(benchmark::State &state, std::shared_ptr<spdlog::logger> logger) {
+    int i = 0;
+    benchmark::DoNotOptimize(i);       // prevent unused warnings
+    benchmark::DoNotOptimize(logger);  // prevent unused warnings
+    for (auto _ : state) {
         SPDLOG_LOGGER_DEBUG(logger, "Hello logger: msg number {}...............", i++);
+    }
+}
+
+void bench_disabled_macro_global_logger(benchmark::State &state,
+                                        std::shared_ptr<spdlog::logger> logger) {
+    spdlog::set_default_logger(std::move(logger));
+    int i = 0;
+    benchmark::DoNotOptimize(i);       // prevent unused warnings
+    benchmark::DoNotOptimize(logger);  // prevent unused warnings
+    for (auto _ : state) {
         SPDLOG_DEBUG("Hello logger: msg number {}...............", i++);
     }
 }
 
 #ifdef __linux__
-void bench_dev_null()
-{
+void bench_dev_null() {
     auto dev_null_st = spdlog::basic_logger_st("/dev/null_st", "/dev/null");
-    benchmark::RegisterBenchmark("/dev/null_st", bench_logger, std::move(dev_null_st))->UseRealTime();
+    benchmark::RegisterBenchmark("/dev/null_st", bench_logger, std::move(dev_null_st))
+        ->UseRealTime();
     spdlog::drop("/dev/null_st");
 
     auto dev_null_mt = spdlog::basic_logger_mt("/dev/null_mt", "/dev/null");
-    benchmark::RegisterBenchmark("/dev/null_mt", bench_logger, std::move(dev_null_mt))->UseRealTime();
+    benchmark::RegisterBenchmark("/dev/null_mt", bench_logger, std::move(dev_null_mt))
+        ->UseRealTime();
     spdlog::drop("/dev/null_mt");
 }
-#endif // __linux__
+#endif  // __linux__
 
-int main(int argc, char *argv[])
-{
+int main(int argc, char *argv[]) {
     using spdlog::sinks::null_sink_mt;
     using spdlog::sinks::null_sink_st;
 
@@ -76,76 +92,108 @@ int main(int argc, char *argv[])
     auto full_bench = argc > 1 && std::string(argv[1]) == "full";
 
     // disabled loggers
-    auto disabled_logger = std::make_shared<spdlog::logger>("bench", std::make_shared<null_sink_mt>());
+    auto disabled_logger =
+        std::make_shared<spdlog::logger>("bench", std::make_shared<null_sink_mt>());
     disabled_logger->set_level(spdlog::level::off);
     benchmark::RegisterBenchmark("disabled-at-compile-time", bench_disabled_macro, disabled_logger);
+    benchmark::RegisterBenchmark("disabled-at-compile-time (global logger)",
+                                 bench_disabled_macro_global_logger, disabled_logger);
     benchmark::RegisterBenchmark("disabled-at-runtime", bench_logger, disabled_logger);
+    benchmark::RegisterBenchmark("disabled-at-runtime (global logger)", bench_global_logger,
+                                 disabled_logger);
     // with backtrace of 64
-    auto tracing_disabled_logger = std::make_shared<spdlog::logger>("bench", std::make_shared<null_sink_mt>());
+    auto tracing_disabled_logger =
+        std::make_shared<spdlog::logger>("bench", std::make_shared<null_sink_mt>());
     tracing_disabled_logger->enable_backtrace(64);
-    benchmark::RegisterBenchmark("disabled-at-runtime/backtrace", bench_logger, tracing_disabled_logger);
+    benchmark::RegisterBenchmark("disabled-at-runtime/backtrace", bench_logger,
+                                 tracing_disabled_logger);
 
-    auto null_logger_st = std::make_shared<spdlog::logger>("bench", std::make_shared<null_sink_st>());
-    benchmark::RegisterBenchmark("null_sink_st (500_bytes c_str)", bench_c_string, std::move(null_logger_st));
+    auto null_logger_st =
+        std::make_shared<spdlog::logger>("bench", std::make_shared<null_sink_st>());
+    benchmark::RegisterBenchmark("null_sink_st (500_bytes c_str)", bench_c_string,
+                                 std::move(null_logger_st));
     benchmark::RegisterBenchmark("null_sink_st", bench_logger, null_logger_st);
+    benchmark::RegisterBenchmark("null_sink_st (global logger)", bench_global_logger,
+                                 null_logger_st);
     // with backtrace of 64
-    auto tracing_null_logger_st = std::make_shared<spdlog::logger>("bench", std::make_shared<null_sink_st>());
+    auto tracing_null_logger_st =
+        std::make_shared<spdlog::logger>("bench", std::make_shared<null_sink_st>());
     tracing_null_logger_st->enable_backtrace(64);
     benchmark::RegisterBenchmark("null_sink_st/backtrace", bench_logger, tracing_null_logger_st);
 
-#ifdef __linux
+#ifdef __linux__
     bench_dev_null();
-#endif // __linux__
+#endif  // __linux__
 
-    if (full_bench)
-    {
+    if (full_bench) {
         // basic_st
         auto basic_st = spdlog::basic_logger_st("basic_st", "latency_logs/basic_st.log", true);
         benchmark::RegisterBenchmark("basic_st", bench_logger, std::move(basic_st))->UseRealTime();
         spdlog::drop("basic_st");
         // with backtrace of 64
-        auto tracing_basic_st = spdlog::basic_logger_st("tracing_basic_st", "latency_logs/tracing_basic_st.log", true);
+        auto tracing_basic_st =
+            spdlog::basic_logger_st("tracing_basic_st", "latency_logs/tracing_basic_st.log", true);
         tracing_basic_st->enable_backtrace(64);
-        benchmark::RegisterBenchmark("basic_st/backtrace", bench_logger, std::move(tracing_basic_st))->UseRealTime();
+        benchmark::RegisterBenchmark("basic_st/backtrace", bench_logger,
+                                     std::move(tracing_basic_st))
+            ->UseRealTime();
         spdlog::drop("tracing_basic_st");
 
         // rotating st
-        auto rotating_st = spdlog::rotating_logger_st("rotating_st", "latency_logs/rotating_st.log", file_size, rotating_files);
-        benchmark::RegisterBenchmark("rotating_st", bench_logger, std::move(rotating_st))->UseRealTime();
+        auto rotating_st = spdlog::rotating_logger_st("rotating_st", "latency_logs/rotating_st.log",
+                                                      file_size, rotating_files);
+        benchmark::RegisterBenchmark("rotating_st", bench_logger, std::move(rotating_st))
+            ->UseRealTime();
         spdlog::drop("rotating_st");
         // with backtrace of 64
-        auto tracing_rotating_st =
-            spdlog::rotating_logger_st("tracing_rotating_st", "latency_logs/tracing_rotating_st.log", file_size, rotating_files);
-        benchmark::RegisterBenchmark("rotating_st/backtrace", bench_logger, std::move(tracing_rotating_st))->UseRealTime();
+        auto tracing_rotating_st = spdlog::rotating_logger_st(
+            "tracing_rotating_st", "latency_logs/tracing_rotating_st.log", file_size,
+            rotating_files);
+        benchmark::RegisterBenchmark("rotating_st/backtrace", bench_logger,
+                                     std::move(tracing_rotating_st))
+            ->UseRealTime();
         spdlog::drop("tracing_rotating_st");
 
         // daily st
         auto daily_st = spdlog::daily_logger_mt("daily_st", "latency_logs/daily_st.log");
         benchmark::RegisterBenchmark("daily_st", bench_logger, std::move(daily_st))->UseRealTime();
         spdlog::drop("daily_st");
-        auto tracing_daily_st = spdlog::daily_logger_mt("tracing_daily_st", "latency_logs/daily_st.log");
-        benchmark::RegisterBenchmark("daily_st/backtrace", bench_logger, std::move(tracing_daily_st))->UseRealTime();
+        auto tracing_daily_st =
+            spdlog::daily_logger_mt("tracing_daily_st", "latency_logs/daily_st.log");
+        benchmark::RegisterBenchmark("daily_st/backtrace", bench_logger,
+                                     std::move(tracing_daily_st))
+            ->UseRealTime();
         spdlog::drop("tracing_daily_st");
 
         //
         // Multi threaded bench, 10 loggers using same logger concurrently
         //
-        auto null_logger_mt = std::make_shared<spdlog::logger>("bench", std::make_shared<null_sink_mt>());
-        benchmark::RegisterBenchmark("null_sink_mt", bench_logger, null_logger_mt)->Threads(n_threads)->UseRealTime();
+        auto null_logger_mt =
+            std::make_shared<spdlog::logger>("bench", std::make_shared<null_sink_mt>());
+        benchmark::RegisterBenchmark("null_sink_mt", bench_logger, null_logger_mt)
+            ->Threads(n_threads)
+            ->UseRealTime();
 
         // basic_mt
         auto basic_mt = spdlog::basic_logger_mt("basic_mt", "latency_logs/basic_mt.log", true);
-        benchmark::RegisterBenchmark("basic_mt", bench_logger, std::move(basic_mt))->Threads(n_threads)->UseRealTime();
+        benchmark::RegisterBenchmark("basic_mt", bench_logger, std::move(basic_mt))
+            ->Threads(n_threads)
+            ->UseRealTime();
         spdlog::drop("basic_mt");
 
         // rotating mt
-        auto rotating_mt = spdlog::rotating_logger_mt("rotating_mt", "latency_logs/rotating_mt.log", file_size, rotating_files);
-        benchmark::RegisterBenchmark("rotating_mt", bench_logger, std::move(rotating_mt))->Threads(n_threads)->UseRealTime();
+        auto rotating_mt = spdlog::rotating_logger_mt("rotating_mt", "latency_logs/rotating_mt.log",
+                                                      file_size, rotating_files);
+        benchmark::RegisterBenchmark("rotating_mt", bench_logger, std::move(rotating_mt))
+            ->Threads(n_threads)
+            ->UseRealTime();
         spdlog::drop("rotating_mt");
 
         // daily mt
         auto daily_mt = spdlog::daily_logger_mt("daily_mt", "latency_logs/daily_mt.log");
-        benchmark::RegisterBenchmark("daily_mt", bench_logger, std::move(daily_mt))->Threads(n_threads)->UseRealTime();
+        benchmark::RegisterBenchmark("daily_mt", bench_logger, std::move(daily_mt))
+            ->Threads(n_threads)
+            ->UseRealTime();
         spdlog::drop("daily_mt");
     }
 
@@ -153,13 +201,19 @@ int main(int argc, char *argv[])
     auto queue_size = 1024 * 1024 * 3;
     auto tp = std::make_shared<spdlog::details::thread_pool>(queue_size, 1);
     auto async_logger = std::make_shared<spdlog::async_logger>(
-        "async_logger", std::make_shared<null_sink_mt>(), std::move(tp), spdlog::async_overflow_policy::overrun_oldest);
-    benchmark::RegisterBenchmark("async_logger", bench_logger, async_logger)->Threads(n_threads)->UseRealTime();
+        "async_logger", std::make_shared<null_sink_mt>(), std::move(tp),
+        spdlog::async_overflow_policy::overrun_oldest);
+    benchmark::RegisterBenchmark("async_logger", bench_logger, async_logger)
+        ->Threads(n_threads)
+        ->UseRealTime();
 
     auto async_logger_tracing = std::make_shared<spdlog::async_logger>(
-        "async_logger_tracing", std::make_shared<null_sink_mt>(), std::move(tp), spdlog::async_overflow_policy::overrun_oldest);
+        "async_logger_tracing", std::make_shared<null_sink_mt>(), std::move(tp),
+        spdlog::async_overflow_policy::overrun_oldest);
     async_logger_tracing->enable_backtrace(32);
-    benchmark::RegisterBenchmark("async_logger/tracing", bench_logger, async_logger_tracing)->Threads(n_threads)->UseRealTime();
+    benchmark::RegisterBenchmark("async_logger/tracing", bench_logger, async_logger_tracing)
+        ->Threads(n_threads)
+        ->UseRealTime();
 
     benchmark::Initialize(&argc, argv);
     benchmark::RunSpecifiedBenchmarks();

bench/utils.h

@@ -11,9 +11,8 @@
 
 namespace utils {
 
-template<typename T>
-inline std::string format(const T &value)
-{
+template <typename T>
+inline std::string format(const T &value) {
     static std::locale loc("");
     std::stringstream ss;
     ss.imbue(loc);
@@ -21,9 +20,8 @@ inline std::string format(const T &value)
     return ss.str();
 }
 
-template<>
-inline std::string format(const double &value)
-{
+template <>
+inline std::string format(const double &value) {
     static std::locale loc("");
     std::stringstream ss;
     ss.imbue(loc);
@@ -31,4 +29,4 @@ inline std::string format(const double &value)
     return ss.str();
 }
 
-} // namespace utils
+}  // namespace utils

cmake/pch.h.in

@@ -10,7 +10,6 @@
 
 // details/file_helper-inl.h
 // details/os-inl.h
-// fmt/bundled/core.h
 // fmt/bundled/posix.h
 // logger-inl.h
 // sinks/daily_file_sink.h
@@ -23,7 +22,6 @@
 
 // details/os-inl.h
 // details/pattern_formatter-inl.h
-// fmt/bundled/core.h
 // fmt/bundled/format-inl.h
 #include <cstring>
 
@@ -73,7 +71,6 @@
 // details/registry.h
 // details/tcp_client-windows.h
 // details/tcp_client.h
-// fmt/bundled/core.h
 // sinks/android_sink.h
 // sinks/ansicolor_sink.h
 // sinks/basic_file_sink.h
@@ -150,7 +147,6 @@
 
 // common.h
 // details/fmt_helper.h
-// fmt/bundled/core.h
 // fmt/bundled/ranges.h
 #include <type_traits>
 
@@ -255,4 +251,4 @@
 #include <mutex>
 
 // spdlog
-#include <spdlog/common.h>
+#include <spdlog/common.h>

cmake/spdlog.pc.in

@@ -1,7 +1,7 @@
 prefix=@CMAKE_INSTALL_PREFIX@
 exec_prefix=${prefix}
-includedir=${prefix}/include
-libdir=${exec_prefix}/@CMAKE_INSTALL_LIBDIR@
+includedir=@PKG_CONFIG_INCLUDEDIR@
+libdir=@PKG_CONFIG_LIBDIR@
 
 Name: lib@PROJECT_NAME@
 Description: Fast C++ logging library.

cmake/spdlogCPack.cmake

@@ -18,23 +18,37 @@ set(CPACK_PACKAGE_RELOCATABLE ON CACHE BOOL "Build relocatable package")
 
 set(CPACK_RPM_PACKAGE_LICENSE "MIT")
 set(CPACK_RPM_PACKAGE_GROUP "Development/Libraries")
+set(CPACK_DEBIAN_PACKAGE_SECTION "libs")
 set(CPACK_RPM_PACKAGE_URL ${CPACK_PROJECT_URL})
+set(CPACK_DEBIAN_PACKAGE_HOMEPAGE ${CPACK_PROJECT_URL})
 set(CPACK_RPM_PACKAGE_DESCRIPTION "Very fast, header-only/compiled, C++ logging library.")
+set(CPACK_DEBIAN_PACKAGE_DESCRIPTION "Very fast, header-only/compiled, C++ logging library.")
 
 if(CPACK_PACKAGE_NAME)
     set(CPACK_RPM_FILE_NAME "${CPACK_PACKAGE_NAME}-${CPACK_PACKAGE_VERSION}")
+    set(CPACK_DEBIAN_FILE_NAME "${CPACK_PACKAGE_NAME}-${CPACK_PACKAGE_VERSION}")
 else()
     set(CPACK_RPM_FILE_NAME "${PROJECT_NAME}-${CPACK_PACKAGE_VERSION}")
+    set(CPACK_DEBIAN_FILE_NAME "${PROJECT_NAME}-${CPACK_PACKAGE_VERSION}")
+    set(CPACK_RPM_PACKAGE_NAME "${PROJECT_NAME}")
+    set(CPACK_DEBIAN_PACKAGE_NAME "${PROJECT_NAME}")
 endif()
 
 if(CPACK_RPM_PACKAGE_RELEASE)
     set(CPACK_RPM_FILE_NAME "${CPACK_RPM_FILE_NAME}-${CPACK_RPM_PACKAGE_RELEASE}")
 endif()
+if(CPACK_DEBIAN_PACKAGE_RELEASE)
+    set(CPACK_DEBIAN_FILE_NAME "${CPACK_DEBIAN_FILE_NAME}-${CPACK_DEBIAN_PACKAGE_RELEASE}")
+endif()
 
 if(CPACK_RPM_PACKAGE_ARCHITECTURE)
     set(CPACK_RPM_FILE_NAME "${CPACK_RPM_FILE_NAME}.${CPACK_RPM_PACKAGE_ARCHITECTURE}")
 endif()
+if(CPACK_DEBIAN_PACKAGE_ARCHITECTURE)
+    set(CPACK_DEBIAN_FILE_NAME "${CPACK_DEBIAN_FILE_NAME}.${CPACK_DEBIAN_PACKAGE_ARCHITECTURE}")
+endif()
 set(CPACK_RPM_FILE_NAME "${CPACK_RPM_FILE_NAME}.rpm")
+set(CPACK_DEBIAN_FILE_NAME "${CPACK_DEBIAN_FILE_NAME}.deb")
 
 if(NOT CPACK_PACKAGE_RELOCATABLE)
     # Depend on pkgconfig rpm to create the system pkgconfig folder

cmake/spdlogConfig.cmake.in

@@ -1,15 +1,20 @@
 # Copyright(c) 2019 spdlog authors
 # Distributed under the MIT License (http://opensource.org/licenses/MIT)
 
+@PACKAGE_INIT@
+
 find_package(Threads REQUIRED)
 
 set(SPDLOG_FMT_EXTERNAL @SPDLOG_FMT_EXTERNAL@)
+set(SPDLOG_FMT_EXTERNAL_HO @SPDLOG_FMT_EXTERNAL_HO@)
 set(config_targets_file @config_targets_file@)
 
-if(SPDLOG_FMT_EXTERNAL)
+if(SPDLOG_FMT_EXTERNAL OR SPDLOG_FMT_EXTERNAL_HO)
     include(CMakeFindDependencyMacro)
     find_dependency(fmt CONFIG)
 endif()
 
 
 include("${CMAKE_CURRENT_LIST_DIR}/${config_targets_file}")
+
+check_required_components(spdlog)

cmake/utils.cmake

@@ -42,13 +42,14 @@ function(spdlog_enable_warnings target_name)
                     -Wextra
                     -Wconversion
                     -pedantic
+                    -Werror
                     -Wfatal-errors>
                     $<$<CXX_COMPILER_ID:MSVC>:${MSVC_OPTIONS}>)
     endif()
 endfunction()
 
 # Enable address sanitizer (gcc/clang only)
-function(spdlog_enable_sanitizer target_name)
+function(spdlog_enable_addr_sanitizer target_name)
     if(NOT CMAKE_CXX_COMPILER_ID MATCHES "GNU|Clang")
         message(FATAL_ERROR "Sanitizer supported only for gcc/clang")
     endif()
@@ -57,5 +58,16 @@ function(spdlog_enable_sanitizer target_name)
     target_compile_options(${target_name} PRIVATE -fno-sanitize=signed-integer-overflow)
     target_compile_options(${target_name} PRIVATE -fno-sanitize-recover=all)
     target_compile_options(${target_name} PRIVATE -fno-omit-frame-pointer)
-    target_link_libraries(${target_name} PRIVATE -fsanitize=address,undefined -fuse-ld=gold)
+    target_link_libraries(${target_name} PRIVATE -fsanitize=address,undefined)
+endfunction()
+
+# Enable thread sanitizer (gcc/clang only)
+function(spdlog_enable_thread_sanitizer target_name)
+    if(NOT CMAKE_CXX_COMPILER_ID MATCHES "GNU|Clang")
+        message(FATAL_ERROR "Sanitizer supported only for gcc/clang")
+    endif()
+    message(STATUS "Thread sanitizer enabled")
+    target_compile_options(${target_name} PRIVATE -fsanitize=thread)
+    target_compile_options(${target_name} PRIVATE -fno-omit-frame-pointer)
+    target_link_libraries(${target_name} PRIVATE -fsanitize=thread)
 endfunction()

cmake/version.rc.in

@@ -1,5 +1,5 @@
 #define APSTUDIO_READONLY_SYMBOLS
-#include "winres.h"
+#include <windows.h>
 #undef APSTUDIO_READONLY_SYMBOLS
 
 LANGUAGE LANG_ENGLISH, SUBLANG_ENGLISH_US

example/CMakeLists.txt

@@ -1,6 +1,6 @@
 # Copyright(c) 2019 spdlog authors Distributed under the MIT License (http://opensource.org/licenses/MIT)
 
-cmake_minimum_required(VERSION 3.2)
+cmake_minimum_required(VERSION 3.11)
 project(spdlog_examples CXX)
 
 if(NOT TARGET spdlog)
@@ -12,7 +12,7 @@ endif()
 # Example of using pre-compiled library
 # ---------------------------------------------------------------------------------------
 add_executable(example example.cpp)
-target_link_libraries(example PRIVATE spdlog::spdlog)
+target_link_libraries(example PRIVATE spdlog::spdlog $<$<BOOL:${MINGW}>:ws2_32>)
 
 # ---------------------------------------------------------------------------------------
 # Example of using header-only library

example/example.cpp

@@ -5,73 +5,87 @@
 // spdlog usage example
 
 #include <cstdio>
+#include <chrono>
 
 void load_levels_example();
 void stdout_logger_example();
 void basic_example();
 void rotating_example();
 void daily_example();
+void callback_example();
 void async_example();
 void binary_example();
+void vector_example();
+void stopwatch_example();
 void trace_example();
 void multi_sink_example();
 void user_defined_example();
 void err_handler_example();
 void syslog_example();
+void udp_example();
 void custom_flags_example();
+void file_events_example();
+void replace_default_logger_example();
+void mdc_example();
 
 #include "spdlog/spdlog.h"
-#include "spdlog/cfg/env.h" // for loading levels from the environment variable
+#include "spdlog/cfg/env.h"   // support for loading levels from the environment variable
+#include "spdlog/fmt/ostr.h"  // support for user defined types
 
-int main(int, char *[])
-{
-    // Log levels can be loaded from argv/env using "SPDLOG_LEVEL"
-    load_levels_example();
+int main(int, char *[]) {
+    try {
+        // Log levels can be loaded from argv/env using "SPDLOG_LEVEL"
+        load_levels_example();
 
-    spdlog::info("Welcome to spdlog version {}.{}.{}  !", SPDLOG_VER_MAJOR, SPDLOG_VER_MINOR, SPDLOG_VER_PATCH);
+        spdlog::info("Welcome to spdlog version {}.{}.{}  !", SPDLOG_VER_MAJOR, SPDLOG_VER_MINOR,
+                     SPDLOG_VER_PATCH);
 
-    spdlog::warn("Easy padding in numbers like {:08d}", 12);
-    spdlog::critical("Support for int: {0:d};  hex: {0:x};  oct: {0:o}; bin: {0:b}", 42);
-    spdlog::info("Support for floats {:03.2f}", 1.23456);
-    spdlog::info("Positional args are {1} {0}..", "too", "supported");
-    spdlog::info("{:>8} aligned, {:<8} aligned", "right", "left");
+        spdlog::warn("Easy padding in numbers like {:08d}", 12);
+        spdlog::critical("Support for int: {0:d};  hex: {0:x};  oct: {0:o}; bin: {0:b}", 42);
+        spdlog::info("Support for floats {:03.2f}", 1.23456);
+        spdlog::info("Positional args are {1} {0}..", "too", "supported");
+        spdlog::info("{:>8} aligned, {:<8} aligned", "right", "left");
 
-    // Runtime log levels
-    spdlog::set_level(spdlog::level::info); // Set global log level to info
-    spdlog::debug("This message should not be displayed!");
-    spdlog::set_level(spdlog::level::trace); // Set specific logger's log level
-    spdlog::debug("This message should be displayed..");
+        // Runtime log levels
+        spdlog::set_level(spdlog::level::info);  // Set global log level to info
+        spdlog::debug("This message should not be displayed!");
+        spdlog::set_level(spdlog::level::trace);  // Set specific logger's log level
+        spdlog::debug("This message should be displayed..");
 
-    // Customize msg format for all loggers
-    spdlog::set_pattern("[%H:%M:%S %z] [%^%L%$] [thread %t] %v");
-    spdlog::info("This an info message with custom format");
-    spdlog::set_pattern("%+"); // back to default format
-    spdlog::set_level(spdlog::level::info);
+        // Customize msg format for all loggers
+        spdlog::set_pattern("[%H:%M:%S %z] [%^%L%$] [thread %t] %v");
+        spdlog::info("This an info message with custom format");
+        spdlog::set_pattern("%+");  // back to default format
+        spdlog::set_level(spdlog::level::info);
 
-    // Backtrace support
-    // Loggers can store in a ring buffer all messages (including debug/trace) for later inspection.
-    // When needed, call dump_backtrace() to see what happened:
-    spdlog::enable_backtrace(10); // create ring buffer with capacity of 10  messages
-    for (int i = 0; i < 100; i++)
-    {
-        spdlog::debug("Backtrace message {}", i); // not logged..
-    }
-    // e.g. if some error happened:
-    spdlog::dump_backtrace(); // log them now!
+        // Backtrace support
+        // Loggers can store in a ring buffer all messages (including debug/trace) for later
+        // inspection. When needed, call dump_backtrace() to see what happened:
+        spdlog::enable_backtrace(10);  // create ring buffer with capacity of 10  messages
+        for (int i = 0; i < 100; i++) {
+            spdlog::debug("Backtrace message {}", i);  // not logged..
+        }
+        // e.g. if some error happened:
+        spdlog::dump_backtrace();  // log them now!
 
-    try
-    {
         stdout_logger_example();
         basic_example();
         rotating_example();
         daily_example();
+        callback_example();
         async_example();
         binary_example();
+        vector_example();
         multi_sink_example();
         user_defined_example();
         err_handler_example();
         trace_example();
+        stopwatch_example();
+        udp_example();
         custom_flags_example();
+        file_events_example();
+        replace_default_logger_example();
+        mdc_example();
 
         // Flush all *registered* loggers using a worker thread every 3 seconds.
         // note: registered loggers *must* be thread safe for this to work correctly!
@@ -86,8 +100,7 @@ int main(int, char *[])
     }
 
     // Exceptions will only be thrown upon failed logger or sink construction (not during logging).
-    catch (const spdlog::spdlog_ex &ex)
-    {
+    catch (const spdlog::spdlog_ex &ex) {
         std::printf("Log initialization failed: %s\n", ex.what());
         return 1;
     }
@@ -95,8 +108,7 @@ int main(int, char *[])
 
 #include "spdlog/sinks/stdout_color_sinks.h"
 // or #include "spdlog/sinks/stdout_sinks.h" if no colors needed.
-void stdout_logger_example()
-{
+void stdout_logger_example() {
     // Create color multi threaded logger.
     auto console = spdlog::stdout_color_mt("console");
     // or for stderr:
@@ -104,32 +116,41 @@ void stdout_logger_example()
 }
 
 #include "spdlog/sinks/basic_file_sink.h"
-void basic_example()
-{
+void basic_example() {
     // Create basic file logger (not rotated).
-    auto my_logger = spdlog::basic_logger_mt("file_logger", "logs/basic-log.txt");
+    auto my_logger = spdlog::basic_logger_mt("file_logger", "logs/basic-log.txt", true);
 }
 
 #include "spdlog/sinks/rotating_file_sink.h"
-void rotating_example()
-{
+void rotating_example() {
     // Create a file rotating logger with 5mb size max and 3 rotated files.
-    auto rotating_logger = spdlog::rotating_logger_mt("some_logger_name", "logs/rotating.txt", 1048576 * 5, 3);
+    auto rotating_logger =
+        spdlog::rotating_logger_mt("some_logger_name", "logs/rotating.txt", 1048576 * 5, 3);
 }
 
 #include "spdlog/sinks/daily_file_sink.h"
-void daily_example()
-{
+void daily_example() {
     // Create a daily logger - a new file is created every day on 2:30am.
     auto daily_logger = spdlog::daily_logger_mt("daily_logger", "logs/daily.txt", 2, 30);
 }
 
+#include "spdlog/sinks/callback_sink.h"
+void callback_example() {
+    // Create the logger
+    auto logger = spdlog::callback_logger_mt("custom_callback_logger",
+                                             [](const spdlog::details::log_msg & /*msg*/) {
+                                                 // do what you need to do with msg
+                                             });
+}
+
 #include "spdlog/cfg/env.h"
-void load_levels_example()
-{
-    // Set the log level to "info" and mylogger to to "trace":
+void load_levels_example() {
+    // Set the log level to "info" and mylogger to "trace":
     // SPDLOG_LEVEL=info,mylogger=trace && ./example
     spdlog::cfg::load_env_levels();
+    // or specify the env variable name:
+    // MYAPP_LEVEL=info,mylogger=trace && ./example
+    // spdlog::cfg::load_env_levels("MYAPP_LEVEL");
     // or from command line:
     // ./example SPDLOG_LEVEL=info,mylogger=trace
     // #include "spdlog/cfg/argv.h" // for loading levels from argv
@@ -137,16 +158,17 @@ void load_levels_example()
 }
 
 #include "spdlog/async.h"
-void async_example()
-{
+void async_example() {
     // Default thread pool settings can be modified *before* creating the async logger:
     // spdlog::init_thread_pool(32768, 1); // queue with max 32k items 1 backing thread.
-    auto async_file = spdlog::basic_logger_mt<spdlog::async_factory>("async_file_logger", "logs/async_log.txt");
+    auto async_file =
+        spdlog::basic_logger_mt<spdlog::async_factory>("async_file_logger", "logs/async_log.txt");
     // alternatively:
-    // auto async_file = spdlog::create_async<spdlog::sinks::basic_file_sink_mt>("async_file_logger", "logs/async_log.txt");
+    // auto async_file =
+    // spdlog::create_async<spdlog::sinks::basic_file_sink_mt>("async_file_logger",
+    // "logs/async_log.txt");
 
-    for (int i = 1; i < 101; ++i)
-    {
+    for (int i = 1; i < 101; ++i) {
         async_file->info("Async message #{}", i);
     }
 }
@@ -160,16 +182,16 @@ void async_example()
 // {:p} - don't print the position on each line start.
 // {:n} - don't split the output to lines.
 
-#include "spdlog/fmt/bin_to_hex.h"
-void binary_example()
-{
-    std::vector<char> buf(80);
-    for (int i = 0; i < 80; i++)
-    {
+#if !defined SPDLOG_USE_STD_FORMAT || defined(_MSC_VER)
+    #include "spdlog/fmt/bin_to_hex.h"
+void binary_example() {
+    std::vector<char> buf;
+    for (int i = 0; i < 80; i++) {
         buf.push_back(static_cast<char>(i & 0xff));
     }
     spdlog::info("Binary example: {}", spdlog::to_hex(buf));
-    spdlog::info("Another binary example:{:n}", spdlog::to_hex(std::begin(buf), std::begin(buf) + 10));
+    spdlog::info("Another binary example:{:n}",
+                 spdlog::to_hex(std::begin(buf), std::begin(buf) + 10));
     // more examples:
     // logger->info("uppercase: {:X}", spdlog::to_hex(buf));
     // logger->info("uppercase, no delimiters: {:Xs}", spdlog::to_hex(buf));
@@ -177,11 +199,29 @@ void binary_example()
     // logger->info("hexdump style: {:a}", spdlog::to_hex(buf));
     // logger->info("hexdump style, 20 chars per line {:a}", spdlog::to_hex(buf, 20));
 }
+#else
+void binary_example() {
+    // not supported with std::format yet
+}
+#endif
+
+// Log a vector of numbers
+#ifndef SPDLOG_USE_STD_FORMAT
+    #include "spdlog/fmt/ranges.h"
+void vector_example() {
+    std::vector<int> vec = {1, 2, 3};
+    spdlog::info("Vector example: {}", vec);
+}
+
+#else
+void vector_example() {}
+#endif
+
+// ! DSPDLOG_USE_STD_FORMAT
 
 // Compile time log levels.
 // define SPDLOG_ACTIVE_LEVEL to required level (e.g. SPDLOG_LEVEL_TRACE)
-void trace_example()
-{
+void trace_example() {
     // trace from default logger
     SPDLOG_TRACE("Some trace message.. {} ,{}", 1, 3.23);
     // debug from default logger
@@ -192,14 +232,31 @@ void trace_example()
     SPDLOG_LOGGER_TRACE(logger, "another trace message");
 }
 
+// stopwatch example
+#include "spdlog/stopwatch.h"
+#include <thread>
+void stopwatch_example() {
+    spdlog::stopwatch sw;
+    std::this_thread::sleep_for(std::chrono::milliseconds(123));
+    spdlog::info("Stopwatch: {} seconds", sw);
+}
+
+#include "spdlog/sinks/udp_sink.h"
+void udp_example() {
+    spdlog::sinks::udp_sink_config cfg("127.0.0.1", 11091);
+    auto my_logger = spdlog::udp_logger_mt("udplog", cfg);
+    my_logger->set_level(spdlog::level::debug);
+    my_logger->info("hello world");
+}
+
 // A logger with multiple sinks (stdout and file) - each with a different format and log level.
-void multi_sink_example()
-{
+void multi_sink_example() {
     auto console_sink = std::make_shared<spdlog::sinks::stdout_color_sink_mt>();
     console_sink->set_level(spdlog::level::warn);
     console_sink->set_pattern("[multi_sink_example] [%^%l%$] %v");
 
-    auto file_sink = std::make_shared<spdlog::sinks::basic_file_sink_mt>("logs/multisink.txt", true);
+    auto file_sink =
+        std::make_shared<spdlog::sinks::basic_file_sink_mt>("logs/multisink.txt", true);
     file_sink->set_level(spdlog::level::trace);
 
     spdlog::logger logger("multi_sink", {console_sink, file_sink});
@@ -208,35 +265,44 @@ void multi_sink_example()
     logger.info("this message should not appear in the console, only in the file");
 }
 
-// User defined types logging by implementing operator<<
-#include "spdlog/fmt/ostr.h" // must be included
-struct my_type
-{
-    int i;
-    template<typename OStream>
-    friend OStream &operator<<(OStream &os, const my_type &c)
-    {
-        return os << "[my_type i=" << c.i << "]";
+// User defined types logging
+struct my_type {
+    int i = 0;
+    explicit my_type(int i)
+        : i(i) {}
+};
+
+#ifndef SPDLOG_USE_STD_FORMAT  // when using fmtlib
+template <>
+struct fmt::formatter<my_type> : fmt::formatter<std::string> {
+    auto format(my_type my, format_context &ctx) const -> decltype(ctx.out()) {
+        return fmt::format_to(ctx.out(), "[my_type i={}]", my.i);
     }
 };
 
-void user_defined_example()
-{
-    spdlog::info("user defined type: {}", my_type{14});
-}
+#else  // when using std::format
+template <>
+struct std::formatter<my_type> : std::formatter<std::string> {
+    auto format(my_type my, format_context &ctx) const -> decltype(ctx.out()) {
+        return std::format_to(ctx.out(), "[my_type i={}]", my.i);
+    }
+};
+#endif
+
+void user_defined_example() { spdlog::info("user defined type: {}", my_type(14)); }
 
 // Custom error handler. Will be triggered on log failure.
-void err_handler_example()
-{
+void err_handler_example() {
     // can be set globally or per logger(logger->set_error_handler(..))
-    spdlog::set_error_handler([](const std::string &msg) { printf("*** Custom log error handler: %s ***\n", msg.c_str()); });
+    spdlog::set_error_handler([](const std::string &msg) {
+        printf("*** Custom log error handler: %s ***\n", msg.c_str());
+    });
 }
 
 // syslog example (linux/osx/freebsd)
 #ifndef _WIN32
-#include "spdlog/sinks/syslog_sink.h"
-void syslog_example()
-{
+    #include "spdlog/sinks/syslog_sink.h"
+void syslog_example() {
     std::string ident = "spdlog-example";
     auto syslog_logger = spdlog::syslog_logger_mt("syslog", ident, LOG_PID);
     syslog_logger->warn("This is warning that will end up in syslog.");
@@ -245,9 +311,8 @@ void syslog_example()
 
 // Android example.
 #if defined(__ANDROID__)
-#include "spdlog/sinks/android_sink.h"
-void android_example()
-{
+    #include "spdlog/sinks/android_sink.h"
+void android_example() {
     std::string tag = "spdlog-android";
     auto android_logger = spdlog::android_logger_mt("android", tag);
     android_logger->critical("Use \"adb shell logcat\" to view this message.");
@@ -257,26 +322,80 @@ void android_example()
 // Log patterns can contain custom flags.
 // this will add custom flag '%*' which will be bound to a <my_formatter_flag> instance
 #include "spdlog/pattern_formatter.h"
-class my_formatter_flag : public spdlog::custom_flag_formatter
-{
+class my_formatter_flag : public spdlog::custom_flag_formatter {
 public:
-    void format(const spdlog::details::log_msg &, const std::tm &, spdlog::memory_buf_t &dest) override
-    {
+    void format(const spdlog::details::log_msg &,
+                const std::tm &,
+                spdlog::memory_buf_t &dest) override {
         std::string some_txt = "custom-flag";
         dest.append(some_txt.data(), some_txt.data() + some_txt.size());
     }
 
-    std::unique_ptr<custom_flag_formatter> clone() const override
-    {
+    std::unique_ptr<custom_flag_formatter> clone() const override {
         return spdlog::details::make_unique<my_formatter_flag>();
     }
 };
 
-void custom_flags_example()
-{
-
-    using spdlog::details::make_unique; // for pre c++14
+void custom_flags_example() {
+    using spdlog::details::make_unique;  // for pre c++14
     auto formatter = make_unique<spdlog::pattern_formatter>();
     formatter->add_flag<my_formatter_flag>('*').set_pattern("[%n] [%*] [%^%l%$] %v");
-    spdlog::set_formatter(std::move(formatter));
+    // set the new formatter using spdlog::set_formatter(formatter) or
+    // logger->set_formatter(formatter) spdlog::set_formatter(std::move(formatter));
 }
+
+void file_events_example() {
+    // pass the spdlog::file_event_handlers to file sinks for open/close log file notifications
+    spdlog::file_event_handlers handlers;
+    handlers.before_open = [](spdlog::filename_t filename) {
+        spdlog::info("Before opening {}", filename);
+    };
+    handlers.after_open = [](spdlog::filename_t filename, std::FILE *fstream) {
+        spdlog::info("After opening {}", filename);
+        fputs("After opening\n", fstream);
+    };
+    handlers.before_close = [](spdlog::filename_t filename, std::FILE *fstream) {
+        spdlog::info("Before closing {}", filename);
+        fputs("Before closing\n", fstream);
+    };
+    handlers.after_close = [](spdlog::filename_t filename) {
+        spdlog::info("After closing {}", filename);
+    };
+    auto file_sink = std::make_shared<spdlog::sinks::basic_file_sink_mt>("logs/events-sample.txt",
+                                                                         true, handlers);
+    spdlog::logger my_logger("some_logger", file_sink);
+    my_logger.info("Some log line");
+}
+
+void replace_default_logger_example() {
+    // store the old logger so we don't break other examples.
+    auto old_logger = spdlog::default_logger();
+
+    auto new_logger = spdlog::basic_logger_mt("new_default_logger", "logs/somelog.txt", true);
+    spdlog::set_default_logger(std::move(new_logger));
+    spdlog::set_level(spdlog::level::info);
+    spdlog::debug("This message should not be displayed!");
+    spdlog::set_level(spdlog::level::trace);
+    spdlog::debug("This message should be displayed..");
+    spdlog::set_default_logger(std::move(old_logger));
+}
+
+// Mapped Diagnostic Context (MDC) is a map that stores key-value pairs (string values) in thread
+// local storage. Each thread maintains its own MDC, which loggers use to append diagnostic
+// information to log outputs. Note: it is not supported in asynchronous mode due to its reliance on
+// thread-local storage.
+
+#ifndef SPDLOG_NO_TLS
+    #include "spdlog/mdc.h"
+void mdc_example() {
+    spdlog::mdc::put("key1", "value1");
+    spdlog::mdc::put("key2", "value2");
+    // if not using the default format, you can use the %& formatter to print mdc data as well
+    spdlog::set_pattern("[%H:%M:%S %z] [%^%L%$] [%&] %v");
+    spdlog::info("Some log message with context");
+}
+#else
+void mdc_example() {
+    // if TLS feature is disabled
+}
+#endif

include/spdlog/async.h

@@ -18,9 +18,9 @@
 #include <spdlog/details/registry.h>
 #include <spdlog/details/thread_pool.h>
 
+#include <functional>
 #include <memory>
 #include <mutex>
-#include <functional>
 
 namespace spdlog {
 
@@ -31,12 +31,10 @@ static const size_t default_async_q_size = 8192;
 // async logger factory - creates async loggers backed with thread pool.
 // if a global thread pool doesn't already exist, create it with default queue
 // size of 8192 items and single thread.
-template<async_overflow_policy OverflowPolicy = async_overflow_policy::block>
-struct async_factory_impl
-{
-    template<typename Sink, typename... SinkArgs>
-    static std::shared_ptr<async_logger> create(std::string logger_name, SinkArgs &&... args)
-    {
+template <async_overflow_policy OverflowPolicy = async_overflow_policy::block>
+struct async_factory_impl {
+    template <typename Sink, typename... SinkArgs>
+    static std::shared_ptr<async_logger> create(std::string logger_name, SinkArgs &&...args) {
         auto &registry_inst = details::registry::instance();
 
         // create global thread pool if not already exists..
@@ -44,14 +42,14 @@ struct async_factory_impl
         auto &mutex = registry_inst.tp_mutex();
         std::lock_guard<std::recursive_mutex> tp_lock(mutex);
         auto tp = registry_inst.get_tp();
-        if (tp == nullptr)
-        {
-            tp = std::make_shared<details::thread_pool>(details::default_async_q_size, 1);
+        if (tp == nullptr) {
+            tp = std::make_shared<details::thread_pool>(details::default_async_q_size, 1U);
             registry_inst.set_tp(tp);
         }
 
         auto sink = std::make_shared<Sink>(std::forward<SinkArgs>(args)...);
-        auto new_logger = std::make_shared<async_logger>(std::move(logger_name), std::move(sink), std::move(tp), OverflowPolicy);
+        auto new_logger = std::make_shared<async_logger>(std::move(logger_name), std::move(sink),
+                                                         std::move(tp), OverflowPolicy);
         registry_inst.initialize_logger(new_logger);
         return new_logger;
     }
@@ -60,34 +58,42 @@ struct async_factory_impl
 using async_factory = async_factory_impl<async_overflow_policy::block>;
 using async_factory_nonblock = async_factory_impl<async_overflow_policy::overrun_oldest>;
 
-template<typename Sink, typename... SinkArgs>
-inline std::shared_ptr<spdlog::logger> create_async(std::string logger_name, SinkArgs &&... sink_args)
-{
-    return async_factory::create<Sink>(std::move(logger_name), std::forward<SinkArgs>(sink_args)...);
+template <typename Sink, typename... SinkArgs>
+inline std::shared_ptr<spdlog::logger> create_async(std::string logger_name,
+                                                    SinkArgs &&...sink_args) {
+    return async_factory::create<Sink>(std::move(logger_name),
+                                       std::forward<SinkArgs>(sink_args)...);
 }
 
-template<typename Sink, typename... SinkArgs>
-inline std::shared_ptr<spdlog::logger> create_async_nb(std::string logger_name, SinkArgs &&... sink_args)
-{
-    return async_factory_nonblock::create<Sink>(std::move(logger_name), std::forward<SinkArgs>(sink_args)...);
+template <typename Sink, typename... SinkArgs>
+inline std::shared_ptr<spdlog::logger> create_async_nb(std::string logger_name,
+                                                       SinkArgs &&...sink_args) {
+    return async_factory_nonblock::create<Sink>(std::move(logger_name),
+                                                std::forward<SinkArgs>(sink_args)...);
 }
 
 // set global thread pool.
-inline void init_thread_pool(size_t q_size, size_t thread_count, std::function<void()> on_thread_start)
-{
-    auto tp = std::make_shared<details::thread_pool>(q_size, thread_count, on_thread_start);
+inline void init_thread_pool(size_t q_size,
+                             size_t thread_count,
+                             std::function<void()> on_thread_start,
+                             std::function<void()> on_thread_stop) {
+    auto tp = std::make_shared<details::thread_pool>(q_size, thread_count, on_thread_start,
+                                                     on_thread_stop);
     details::registry::instance().set_tp(std::move(tp));
 }
 
-// set global thread pool.
-inline void init_thread_pool(size_t q_size, size_t thread_count)
-{
-    init_thread_pool(q_size, thread_count, [] {});
+inline void init_thread_pool(size_t q_size,
+                             size_t thread_count,
+                             std::function<void()> on_thread_start) {
+    init_thread_pool(q_size, thread_count, on_thread_start, [] {});
+}
+
+inline void init_thread_pool(size_t q_size, size_t thread_count) {
+    init_thread_pool(q_size, thread_count, [] {}, [] {});
 }
 
 // get the global thread pool.
-inline std::shared_ptr<spdlog::details::thread_pool> thread_pool()
-{
+inline std::shared_ptr<spdlog::details::thread_pool> thread_pool() {
     return details::registry::instance().get_tp();
 }
-} // namespace spdlog
+}  // namespace spdlog

include/spdlog/async_logger-inl.h

@@ -4,88 +4,80 @@
 #pragma once
 
 #ifndef SPDLOG_HEADER_ONLY
-#include <spdlog/async_logger.h>
+    #include <spdlog/async_logger.h>
 #endif
 
-#include <spdlog/sinks/sink.h>
 #include <spdlog/details/thread_pool.h>
+#include <spdlog/sinks/sink.h>
 
 #include <memory>
 #include <string>
 
-SPDLOG_INLINE spdlog::async_logger::async_logger(
-    std::string logger_name, sinks_init_list sinks_list, std::weak_ptr<details::thread_pool> tp, async_overflow_policy overflow_policy)
-    : async_logger(std::move(logger_name), sinks_list.begin(), sinks_list.end(), std::move(tp), overflow_policy)
-{}
+SPDLOG_INLINE spdlog::async_logger::async_logger(std::string logger_name,
+                                                 sinks_init_list sinks_list,
+                                                 std::weak_ptr<details::thread_pool> tp,
+                                                 async_overflow_policy overflow_policy)
+    : async_logger(std::move(logger_name),
+                   sinks_list.begin(),
+                   sinks_list.end(),
+                   std::move(tp),
+                   overflow_policy) {}
 
-SPDLOG_INLINE spdlog::async_logger::async_logger(
-    std::string logger_name, sink_ptr single_sink, std::weak_ptr<details::thread_pool> tp, async_overflow_policy overflow_policy)
-    : async_logger(std::move(logger_name), {std::move(single_sink)}, std::move(tp), overflow_policy)
-{}
+SPDLOG_INLINE spdlog::async_logger::async_logger(std::string logger_name,
+                                                 sink_ptr single_sink,
+                                                 std::weak_ptr<details::thread_pool> tp,
+                                                 async_overflow_policy overflow_policy)
+    : async_logger(
+          std::move(logger_name), {std::move(single_sink)}, std::move(tp), overflow_policy) {}
 
 // send the log message to the thread pool
-SPDLOG_INLINE void spdlog::async_logger::sink_it_(const details::log_msg &msg)
-{
-    if (auto pool_ptr = thread_pool_.lock())
-    {
-        pool_ptr->post_log(shared_from_this(), msg, overflow_policy_);
-    }
-    else
-    {
-        throw_spdlog_ex("async log: thread pool doesn't exist anymore");
-    }
+SPDLOG_INLINE void spdlog::async_logger::sink_it_(const details::log_msg &msg){
+    SPDLOG_TRY{if (auto pool_ptr = thread_pool_.lock()){
+        pool_ptr -> post_log(shared_from_this(), msg, overflow_policy_);
+}
+else {
+    throw_spdlog_ex("async log: thread pool doesn't exist anymore");
+}
+}
+SPDLOG_LOGGER_CATCH(msg.source)
 }
 
 // send flush request to the thread pool
-SPDLOG_INLINE void spdlog::async_logger::flush_()
-{
-    if (auto pool_ptr = thread_pool_.lock())
-    {
-        pool_ptr->post_flush(shared_from_this(), overflow_policy_);
-    }
-    else
-    {
-        throw_spdlog_ex("async flush: thread pool doesn't exist anymore");
-    }
+SPDLOG_INLINE void spdlog::async_logger::flush_(){
+    SPDLOG_TRY{if (auto pool_ptr = thread_pool_.lock()){
+        pool_ptr -> post_flush(shared_from_this(), overflow_policy_);
+}
+else {
+    throw_spdlog_ex("async flush: thread pool doesn't exist anymore");
+}
+}
+SPDLOG_LOGGER_CATCH(source_loc())
 }
 
 //
 // backend functions - called from the thread pool to do the actual job
 //
-SPDLOG_INLINE void spdlog::async_logger::backend_sink_it_(const details::log_msg &msg)
-{
-    for (auto &sink : sinks_)
-    {
-        if (sink->should_log(msg.level))
-        {
-            SPDLOG_TRY
-            {
-                sink->log(msg);
-            }
-            SPDLOG_LOGGER_CATCH()
+SPDLOG_INLINE void spdlog::async_logger::backend_sink_it_(const details::log_msg &msg) {
+    for (auto &sink : sinks_) {
+        if (sink->should_log(msg.level)) {
+            SPDLOG_TRY { sink->log(msg); }
+            SPDLOG_LOGGER_CATCH(msg.source)
         }
     }
 
-    if (should_flush_(msg))
-    {
+    if (should_flush_(msg)) {
         backend_flush_();
     }
 }
 
-SPDLOG_INLINE void spdlog::async_logger::backend_flush_()
-{
-    for (auto &sink : sinks_)
-    {
-        SPDLOG_TRY
-        {
-            sink->flush();
-        }
-        SPDLOG_LOGGER_CATCH()
+SPDLOG_INLINE void spdlog::async_logger::backend_flush_() {
+    for (auto &sink : sinks_) {
+        SPDLOG_TRY { sink->flush(); }
+        SPDLOG_LOGGER_CATCH(source_loc())
     }
 }
 
-SPDLOG_INLINE std::shared_ptr<spdlog::logger> spdlog::async_logger::clone(std::string new_name)
-{
+SPDLOG_INLINE std::shared_ptr<spdlog::logger> spdlog::async_logger::clone(std::string new_name) {
     auto cloned = std::make_shared<spdlog::async_logger>(*this);
     cloned->name_ = std::move(new_name);
     return cloned;

include/spdlog/async_logger.h

@@ -19,35 +19,41 @@
 namespace spdlog {
 
 // Async overflow policy - block by default.
-enum class async_overflow_policy
-{
-    block,         // Block until message can be enqueued
-    overrun_oldest // Discard oldest message in the queue if full when trying to
-                   // add new item.
+enum class async_overflow_policy {
+    block,           // Block until message can be enqueued
+    overrun_oldest,  // Discard oldest message in the queue if full when trying to
+                     // add new item.
+    discard_new      // Discard new message if the queue is full when trying to add new item.
 };
 
 namespace details {
 class thread_pool;
 }
 
-class SPDLOG_API async_logger final : public std::enable_shared_from_this<async_logger>, public logger
-{
+class SPDLOG_API async_logger final : public std::enable_shared_from_this<async_logger>,
+                                      public logger {
     friend class details::thread_pool;
 
 public:
-    template<typename It>
-    async_logger(std::string logger_name, It begin, It end, std::weak_ptr<details::thread_pool> tp,
-        async_overflow_policy overflow_policy = async_overflow_policy::block)
-        : logger(std::move(logger_name), begin, end)
-        , thread_pool_(std::move(tp))
-        , overflow_policy_(overflow_policy)
-    {}
+    template <typename It>
+    async_logger(std::string logger_name,
+                 It begin,
+                 It end,
+                 std::weak_ptr<details::thread_pool> tp,
+                 async_overflow_policy overflow_policy = async_overflow_policy::block)
+        : logger(std::move(logger_name), begin, end),
+          thread_pool_(std::move(tp)),
+          overflow_policy_(overflow_policy) {}
 
-    async_logger(std::string logger_name, sinks_init_list sinks_list, std::weak_ptr<details::thread_pool> tp,
-        async_overflow_policy overflow_policy = async_overflow_policy::block);
+    async_logger(std::string logger_name,
+                 sinks_init_list sinks_list,
+                 std::weak_ptr<details::thread_pool> tp,
+                 async_overflow_policy overflow_policy = async_overflow_policy::block);
 
-    async_logger(std::string logger_name, sink_ptr single_sink, std::weak_ptr<details::thread_pool> tp,
-        async_overflow_policy overflow_policy = async_overflow_policy::block);
+    async_logger(std::string logger_name,
+                 sink_ptr single_sink,
+                 std::weak_ptr<details::thread_pool> tp,
+                 async_overflow_policy overflow_policy = async_overflow_policy::block);
 
     std::shared_ptr<logger> clone(std::string new_name) override;
 
@@ -61,8 +67,8 @@ private:
     std::weak_ptr<details::thread_pool> thread_pool_;
     async_overflow_policy overflow_policy_;
 };
-} // namespace spdlog
+}  // namespace spdlog
 
 #ifdef SPDLOG_HEADER_ONLY
-#include "async_logger-inl.h"
+    #include "async_logger-inl.h"
 #endif

include/spdlog/cfg/argv.h

@@ -21,25 +21,20 @@ namespace spdlog {
 namespace cfg {
 
 // search for SPDLOG_LEVEL= in the args and use it to init the levels
-void load_argv_levels(int argc, const char **argv)
-{
+inline void load_argv_levels(int argc, const char **argv) {
     const std::string spdlog_level_prefix = "SPDLOG_LEVEL=";
-    for (int i = 1; i < argc; i++)
-    {
+    for (int i = 1; i < argc; i++) {
         std::string arg = argv[i];
-        if (arg.find(spdlog_level_prefix) == 0)
-        {
+        if (arg.find(spdlog_level_prefix) == 0) {
             auto levels_string = arg.substr(spdlog_level_prefix.size());
-            auto levels = helpers::extract_levels(levels_string);
-            details::registry::instance().update_levels(std::move(levels));
+            helpers::load_levels(levels_string);
         }
     }
 }
 
-void load_argv_levels(int argc, char **argv)
-{
+inline void load_argv_levels(int argc, char **argv) {
     load_argv_levels(argc, const_cast<const char **>(argv));
 }
 
-} // namespace cfg
-} // namespace spdlog
+}  // namespace cfg
+}  // namespace spdlog

include/spdlog/cfg/env.h

@@ -3,8 +3,8 @@
 
 #pragma once
 #include <spdlog/cfg/helpers.h>
-#include <spdlog/details/registry.h>
 #include <spdlog/details/os.h>
+#include <spdlog/details/registry.h>
 
 //
 // Init levels and patterns from env variables SPDLOG_LEVEL
@@ -17,7 +17,7 @@
 // export SPDLOG_LEVEL=debug
 //
 // turn off all logging except for logger1:
-// export SPDLOG_LEVEL="off,logger1=debug"
+// export SPDLOG_LEVEL="*=off,logger1=debug"
 //
 
 // turn off all logging except for logger1 and logger2:
@@ -25,12 +25,12 @@
 
 namespace spdlog {
 namespace cfg {
-void load_env_levels()
-{
-    auto env_val = details::os::getenv("SPDLOG_LEVEL");
-    auto levels = helpers::extract_levels(env_val);
-    details::registry::instance().update_levels(std::move(levels));
+inline void load_env_levels(const char* var = "SPDLOG_LEVEL") {
+    auto env_val = details::os::getenv(var);
+    if (!env_val.empty()) {
+        helpers::load_levels(env_val);
+    }
 }
 
-} // namespace cfg
-} // namespace spdlog
+}  // namespace cfg
+}  // namespace spdlog

include/spdlog/cfg/helpers-inl.h

@@ -4,72 +4,64 @@
 #pragma once
 
 #ifndef SPDLOG_HEADER_ONLY
-#include <spdlog/cfg/helpers.h>
+    #include <spdlog/cfg/helpers.h>
 #endif
 
-#include <spdlog/spdlog.h>
 #include <spdlog/details/os.h>
 #include <spdlog/details/registry.h>
 
+#include <algorithm>
+#include <sstream>
 #include <string>
 #include <utility>
-#include <sstream>
 
 namespace spdlog {
 namespace cfg {
 namespace helpers {
 
 // inplace convert to lowercase
-inline std::string &to_lower_(std::string &str)
-{
-    std::transform(
-        str.begin(), str.end(), str.begin(), [](char ch) { return static_cast<char>((ch >= 'A' && ch <= 'Z') ? ch + ('a' - 'A') : ch); });
+inline std::string &to_lower_(std::string &str) {
+    std::transform(str.begin(), str.end(), str.begin(), [](char ch) {
+        return static_cast<char>((ch >= 'A' && ch <= 'Z') ? ch + ('a' - 'A') : ch);
+    });
     return str;
 }
 
 // inplace trim spaces
-inline std::string &trim_(std::string &str)
-{
+inline std::string &trim_(std::string &str) {
     const char *spaces = " \n\r\t";
     str.erase(str.find_last_not_of(spaces) + 1);
     str.erase(0, str.find_first_not_of(spaces));
     return str;
 }
 
-// return (name,value) trimmed pair from given "name=value" string.
+// return (name,value) trimmed pair from the given "name = value" string.
 // return empty string on missing parts
 // "key=val" => ("key", "val")
 // " key  =  val " => ("key", "val")
 // "key=" => ("key", "")
 // "val" => ("", "val")
 
-inline std::pair<std::string, std::string> extract_kv_(char sep, const std::string &str)
-{
+inline std::pair<std::string, std::string> extract_kv_(char sep, const std::string &str) {
     auto n = str.find(sep);
     std::string k, v;
-    if (n == std::string::npos)
-    {
+    if (n == std::string::npos) {
         v = str;
-    }
-    else
-    {
+    } else {
         k = str.substr(0, n);
         v = str.substr(n + 1);
     }
     return std::make_pair(trim_(k), trim_(v));
 }
 
-// return vector of key/value pairs from sequence of "K1=V1,K2=V2,.."
+// return vector of key/value pairs from a sequence of "K1=V1,K2=V2,.."
 // "a=AAA,b=BBB,c=CCC,.." => {("a","AAA"),("b","BBB"),("c", "CCC"),...}
-inline std::unordered_map<std::string, std::string> extract_key_vals_(const std::string &str)
-{
+inline std::unordered_map<std::string, std::string> extract_key_vals_(const std::string &str) {
     std::string token;
     std::istringstream token_stream(str);
     std::unordered_map<std::string, std::string> rv{};
-    while (std::getline(token_stream, token, ','))
-    {
-        if (token.empty())
-        {
+    while (std::getline(token_stream, token, ',')) {
+        if (token.empty()) {
             continue;
         }
         auto kv = extract_kv_('=', token);
@@ -78,26 +70,37 @@ inline std::unordered_map<std::string, std::string> extract_key_vals_(const std:
     return rv;
 }
 
-SPDLOG_INLINE log_levels extract_levels(const std::string &input)
-{
-    auto key_vals = extract_key_vals_(input);
-    log_levels rv;
-
-    for (auto &name_level : key_vals)
-    {
-        auto &logger_name = name_level.first;
-        auto level_name = to_lower_(name_level.second);
-        auto level = level::from_str(level_name);
-        // fallback to "info" if unrecognized level name
-        if (level == level::off && level_name != "off")
-        {
-            level = level::info;
-        }
-        rv.set(logger_name, level);
+SPDLOG_INLINE void load_levels(const std::string &input) {
+    if (input.empty() || input.size() >= 32768) {
+        return;
     }
-    return rv;
+
+    auto key_vals = extract_key_vals_(input);
+    std::unordered_map<std::string, level::level_enum> levels;
+    level::level_enum global_level = level::info;
+    bool global_level_found = false;
+
+    for (auto &name_level : key_vals) {
+        const auto &logger_name = name_level.first;
+        const auto &level_name = to_lower_(name_level.second);
+        auto level = level::from_str(level_name);
+        // ignore unrecognized level names
+        if (level == level::off && level_name != "off") {
+            continue;
+        }
+        if (logger_name.empty())  // no logger name indicates global level
+        {
+            global_level_found = true;
+            global_level = level;
+        } else {
+            levels[logger_name] = level;
+        }
+    }
+
+    details::registry::instance().set_levels(std::move(levels),
+                                             global_level_found ? &global_level : nullptr);
 }
 
-} // namespace helpers
-} // namespace cfg
-} // namespace spdlog
+}  // namespace helpers
+}  // namespace cfg
+}  // namespace spdlog

include/spdlog/cfg/helpers.h

@@ -3,7 +3,8 @@
 
 #pragma once
 
-#include <spdlog/cfg/log_levels.h>
+#include <spdlog/common.h>
+#include <unordered_map>
 
 namespace spdlog {
 namespace cfg {
@@ -17,12 +18,12 @@ namespace helpers {
 // turn off all logging except for logger1: "off,logger1=debug"
 // turn off all logging except for logger1 and logger2: "off,logger1=debug,logger2=info"
 //
-SPDLOG_API log_levels extract_levels(const std::string &txt);
-} // namespace helpers
+SPDLOG_API void load_levels(const std::string &txt);
+}  // namespace helpers
 
-} // namespace cfg
-} // namespace spdlog
+}  // namespace cfg
+}  // namespace spdlog
 
 #ifdef SPDLOG_HEADER_ONLY
-#include "helpers-inl.h"
-#endif // SPDLOG_HEADER_ONLY
+    #include "helpers-inl.h"
+#endif  // SPDLOG_HEADER_ONLY

include/spdlog/cfg/log_levels.h

@@ -1,47 +0,0 @@
-// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
-// Distributed under the MIT License (http://opensource.org/licenses/MIT)
-
-#pragma once
-
-#include <spdlog/common.h>
-#include <string>
-#include <unordered_map>
-
-namespace spdlog {
-namespace cfg {
-class log_levels
-{
-    std::unordered_map<std::string, spdlog::level::level_enum> levels_;
-    spdlog::level::level_enum default_level_ = level::info;
-
-public:
-    void set(const std::string &logger_name, level::level_enum lvl)
-    {
-        if (logger_name.empty())
-        {
-            default_level_ = lvl;
-        }
-        else
-        {
-            levels_[logger_name] = lvl;
-        }
-    }
-
-    void set_default(level::level_enum lvl)
-    {
-        default_level_ = lvl;
-    }
-
-    level::level_enum get(const std::string &logger_name)
-    {
-        auto it = levels_.find(logger_name);
-        return it != levels_.end() ? it->second : default_level_;
-    }
-
-    level::level_enum default_level()
-    {
-        return default_level_;
-    }
-};
-} // namespace cfg
-} // namespace spdlog

include/spdlog/common-inl.h

@@ -4,73 +4,65 @@
 #pragma once
 
 #ifndef SPDLOG_HEADER_ONLY
-#include <spdlog/common.h>
+    #include <spdlog/common.h>
 #endif
 
+#include <algorithm>
+#include <iterator>
+
 namespace spdlog {
 namespace level {
-static string_view_t level_string_views[] SPDLOG_LEVEL_NAMES;
+
+#if __cplusplus >= 201703L
+constexpr
+#endif
+    static string_view_t level_string_views[] SPDLOG_LEVEL_NAMES;
 
 static const char *short_level_names[] SPDLOG_SHORT_LEVEL_NAMES;
 
-SPDLOG_INLINE string_view_t &to_string_view(spdlog::level::level_enum l) SPDLOG_NOEXCEPT
-{
+SPDLOG_INLINE const string_view_t &to_string_view(spdlog::level::level_enum l) SPDLOG_NOEXCEPT {
     return level_string_views[l];
 }
 
-SPDLOG_INLINE const char *to_short_c_str(spdlog::level::level_enum l) SPDLOG_NOEXCEPT
-{
+SPDLOG_INLINE const char *to_short_c_str(spdlog::level::level_enum l) SPDLOG_NOEXCEPT {
     return short_level_names[l];
 }
 
-SPDLOG_INLINE spdlog::level::level_enum from_str(const std::string &name) SPDLOG_NOEXCEPT
-{
-    int level = 0;
-    for (const auto &level_str : level_string_views)
-    {
-        if (level_str == name)
-        {
-            return static_cast<level::level_enum>(level);
-        }
-        level++;
-    }
+SPDLOG_INLINE spdlog::level::level_enum from_str(const std::string &name) SPDLOG_NOEXCEPT {
+    auto it = std::find(std::begin(level_string_views), std::end(level_string_views), name);
+    if (it != std::end(level_string_views))
+        return static_cast<level::level_enum>(std::distance(std::begin(level_string_views), it));
+
     // check also for "warn" and "err" before giving up..
-    if (name == "warn")
-    {
+    if (name == "warn") {
         return level::warn;
     }
-    if (name == "err")
-    {
+    if (name == "err") {
         return level::err;
     }
     return level::off;
 }
-} // namespace level
+}  // namespace level
 
 SPDLOG_INLINE spdlog_ex::spdlog_ex(std::string msg)
-    : msg_(std::move(msg))
-{}
+    : msg_(std::move(msg)) {}
 
-SPDLOG_INLINE spdlog_ex::spdlog_ex(const std::string &msg, int last_errno)
-{
+SPDLOG_INLINE spdlog_ex::spdlog_ex(const std::string &msg, int last_errno) {
+#ifdef SPDLOG_USE_STD_FORMAT
+    msg_ = std::system_error(std::error_code(last_errno, std::generic_category()), msg).what();
+#else
     memory_buf_t outbuf;
-    fmt::format_system_error(outbuf, last_errno, msg);
+    fmt::format_system_error(outbuf, last_errno, msg.c_str());
     msg_ = fmt::to_string(outbuf);
+#endif
 }
 
-SPDLOG_INLINE const char *spdlog_ex::what() const SPDLOG_NOEXCEPT
-{
-    return msg_.c_str();
-}
+SPDLOG_INLINE const char *spdlog_ex::what() const SPDLOG_NOEXCEPT { return msg_.c_str(); }
 
-SPDLOG_INLINE void throw_spdlog_ex(const std::string &msg, int last_errno)
-{
+SPDLOG_INLINE void throw_spdlog_ex(const std::string &msg, int last_errno) {
     SPDLOG_THROW(spdlog_ex(msg, last_errno));
 }
 
-SPDLOG_INLINE void throw_spdlog_ex(std::string msg)
-{
-    SPDLOG_THROW(spdlog_ex(std::move(msg)));
-}
+SPDLOG_INLINE void throw_spdlog_ex(std::string msg) { SPDLOG_THROW(spdlog_ex(std::move(msg))); }
 
-} // namespace spdlog
+}  // namespace spdlog

include/spdlog/common.h

@@ -3,79 +3,121 @@
 
 #pragma once
 
-#include <spdlog/tweakme.h>
 #include <spdlog/details/null_mutex.h>
+#include <spdlog/tweakme.h>
 
 #include <atomic>
 #include <chrono>
+#include <cstdio>
+#include <exception>
+#include <functional>
 #include <initializer_list>
 #include <memory>
-#include <exception>
 #include <string>
 #include <type_traits>
-#include <functional>
+
+#ifdef SPDLOG_USE_STD_FORMAT
+    #include <version>
+    #if __cpp_lib_format >= 202207L
+        #include <format>
+    #else
+        #include <string_view>
+    #endif
+#endif
 
 #ifdef SPDLOG_COMPILED_LIB
-#undef SPDLOG_HEADER_ONLY
-#if defined(_WIN32) && defined(SPDLOG_SHARED_LIB)
-#ifdef spdlog_EXPORTS
-#define SPDLOG_API __declspec(dllexport)
-#else
-#define SPDLOG_API __declspec(dllimport)
-#endif
-#else // !defined(_WIN32) || !defined(SPDLOG_SHARED_LIB)
-#define SPDLOG_API
-#endif
-#define SPDLOG_INLINE
-#else // !defined(SPDLOG_COMPILED_LIB)
-#define SPDLOG_API
-#define SPDLOG_HEADER_ONLY
-#define SPDLOG_INLINE inline
-#endif // #ifdef SPDLOG_COMPILED_LIB
+    #undef SPDLOG_HEADER_ONLY
+    #if defined(SPDLOG_SHARED_LIB)
+        #if defined(_WIN32)
+            #ifdef spdlog_EXPORTS
+                #define SPDLOG_API __declspec(dllexport)
+            #else  // !spdlog_EXPORTS
+                #define SPDLOG_API __declspec(dllimport)
+            #endif
+        #else  // !defined(_WIN32)
+            #define SPDLOG_API __attribute__((visibility("default")))
+        #endif
+    #else  // !defined(SPDLOG_SHARED_LIB)
+        #define SPDLOG_API
+    #endif
+    #define SPDLOG_INLINE
+#else  // !defined(SPDLOG_COMPILED_LIB)
+    #define SPDLOG_API
+    #define SPDLOG_HEADER_ONLY
+    #define SPDLOG_INLINE inline
+#endif  // #ifdef SPDLOG_COMPILED_LIB
 
 #include <spdlog/fmt/fmt.h>
 
-// visual studio upto 2013 does not support noexcept nor constexpr
-#if defined(_MSC_VER) && (_MSC_VER < 1900)
-#define SPDLOG_NOEXCEPT _NOEXCEPT
-#define SPDLOG_CONSTEXPR
+#if !defined(SPDLOG_USE_STD_FORMAT) && \
+    FMT_VERSION >= 80000  // backward compatibility with fmt versions older than 8
+    #define SPDLOG_FMT_RUNTIME(format_string) fmt::runtime(format_string)
+    #define SPDLOG_FMT_STRING(format_string) FMT_STRING(format_string)
+    #if defined(SPDLOG_WCHAR_FILENAMES) || defined(SPDLOG_WCHAR_TO_UTF8_SUPPORT)
+        #include <spdlog/fmt/xchar.h>
+    #endif
 #else
-#define SPDLOG_NOEXCEPT noexcept
-#define SPDLOG_CONSTEXPR constexpr
+    #define SPDLOG_FMT_RUNTIME(format_string) format_string
+    #define SPDLOG_FMT_STRING(format_string) format_string
+#endif
+
+// visual studio up to 2013 does not support noexcept nor constexpr
+#if defined(_MSC_VER) && (_MSC_VER < 1900)
+    #define SPDLOG_NOEXCEPT _NOEXCEPT
+    #define SPDLOG_CONSTEXPR
+#else
+    #define SPDLOG_NOEXCEPT noexcept
+    #define SPDLOG_CONSTEXPR constexpr
+#endif
+
+// If building with std::format, can just use constexpr, otherwise if building with fmt
+// SPDLOG_CONSTEXPR_FUNC needs to be set the same as FMT_CONSTEXPR to avoid situations where
+// a constexpr function in spdlog could end up calling a non-constexpr function in fmt
+// depending on the compiler
+// If fmt determines it can't use constexpr, we should inline the function instead
+#ifdef SPDLOG_USE_STD_FORMAT
+    #define SPDLOG_CONSTEXPR_FUNC constexpr
+#else  // Being built with fmt
+    #if FMT_USE_CONSTEXPR
+        #define SPDLOG_CONSTEXPR_FUNC FMT_CONSTEXPR
+    #else
+        #define SPDLOG_CONSTEXPR_FUNC inline
+    #endif
 #endif
 
 #if defined(__GNUC__) || defined(__clang__)
-#define SPDLOG_DEPRECATED __attribute__((deprecated))
+    #define SPDLOG_DEPRECATED __attribute__((deprecated))
 #elif defined(_MSC_VER)
-#define SPDLOG_DEPRECATED __declspec(deprecated)
+    #define SPDLOG_DEPRECATED __declspec(deprecated)
 #else
-#define SPDLOG_DEPRECATED
+    #define SPDLOG_DEPRECATED
 #endif
 
 // disable thread local on msvc 2013
 #ifndef SPDLOG_NO_TLS
-#if (defined(_MSC_VER) && (_MSC_VER < 1900)) || defined(__cplusplus_winrt)
-#define SPDLOG_NO_TLS 1
-#endif
+    #if (defined(_MSC_VER) && (_MSC_VER < 1900)) || defined(__cplusplus_winrt)
+        #define SPDLOG_NO_TLS 1
+    #endif
 #endif
 
 #ifndef SPDLOG_FUNCTION
-#define SPDLOG_FUNCTION static_cast<const char *>(__FUNCTION__)
+    #define SPDLOG_FUNCTION static_cast<const char *>(__FUNCTION__)
 #endif
 
 #ifdef SPDLOG_NO_EXCEPTIONS
-#define SPDLOG_TRY
-#define SPDLOG_THROW(ex)                                                                                                                   \
-    do                                                                                                                                     \
-    {                                                                                                                                      \
-        printf("spdlog fatal error: %s\n", ex.what());                                                                                     \
-        std::abort();                                                                                                                      \
-    } while (0)
-#define SPDLOG_CATCH_ALL()
+    #define SPDLOG_TRY
+    #define SPDLOG_THROW(ex)                               \
+        do {                                               \
+            printf("spdlog fatal error: %s\n", ex.what()); \
+            std::abort();                                  \
+        } while (0)
+    #define SPDLOG_CATCH_STD
 #else
-#define SPDLOG_TRY try
-#define SPDLOG_THROW(ex) throw(ex)
-#define SPDLOG_CATCH_ALL() catch (...)
+    #define SPDLOG_TRY try
+    #define SPDLOG_THROW(ex) throw(ex)
+    #define SPDLOG_CATCH_STD             \
+        catch (const std::exception &) { \
+        }
 #endif
 
 namespace spdlog {
@@ -88,33 +130,97 @@ class sink;
 
 #if defined(_WIN32) && defined(SPDLOG_WCHAR_FILENAMES)
 using filename_t = std::wstring;
-#define SPDLOG_FILENAME_T(s) L##s
+    // allow macro expansion to occur in SPDLOG_FILENAME_T
+    #define SPDLOG_FILENAME_T_INNER(s) L##s
+    #define SPDLOG_FILENAME_T(s) SPDLOG_FILENAME_T_INNER(s)
 #else
 using filename_t = std::string;
-#define SPDLOG_FILENAME_T(s) s
+    #define SPDLOG_FILENAME_T(s) s
 #endif
 
 using log_clock = std::chrono::system_clock;
 using sink_ptr = std::shared_ptr<sinks::sink>;
 using sinks_init_list = std::initializer_list<sink_ptr>;
 using err_handler = std::function<void(const std::string &err_msg)>;
+#ifdef SPDLOG_USE_STD_FORMAT
+namespace fmt_lib = std;
+
+using string_view_t = std::string_view;
+using memory_buf_t = std::string;
+
+template <typename... Args>
+    #if __cpp_lib_format >= 202207L
+using format_string_t = std::format_string<Args...>;
+    #else
+using format_string_t = std::string_view;
+    #endif
+
+template <class T, class Char = char>
+struct is_convertible_to_basic_format_string
+    : std::integral_constant<bool, std::is_convertible<T, std::basic_string_view<Char>>::value> {};
+
+    #if defined(SPDLOG_WCHAR_FILENAMES) || defined(SPDLOG_WCHAR_TO_UTF8_SUPPORT)
+using wstring_view_t = std::wstring_view;
+using wmemory_buf_t = std::wstring;
+
+template <typename... Args>
+        #if __cpp_lib_format >= 202207L
+using wformat_string_t = std::wformat_string<Args...>;
+        #else
+using wformat_string_t = std::wstring_view;
+        #endif
+    #endif
+    #define SPDLOG_BUF_TO_STRING(x) x
+#else  // use fmt lib instead of std::format
+namespace fmt_lib = fmt;
+
 using string_view_t = fmt::basic_string_view<char>;
-using wstring_view_t = fmt::basic_string_view<wchar_t>;
 using memory_buf_t = fmt::basic_memory_buffer<char, 250>;
 
+template <typename... Args>
+using format_string_t = fmt::format_string<Args...>;
+
+template <class T>
+using remove_cvref_t = typename std::remove_cv<typename std::remove_reference<T>::type>::type;
+
+template <typename Char>
+    #if FMT_VERSION >= 90101
+using fmt_runtime_string = fmt::runtime_format_string<Char>;
+    #else
+using fmt_runtime_string = fmt::basic_runtime<Char>;
+    #endif
+
+// clang doesn't like SFINAE disabled constructor in std::is_convertible<> so have to repeat the
+// condition from basic_format_string here, in addition, fmt::basic_runtime<Char> is only
+// convertible to basic_format_string<Char> but not basic_string_view<Char>
+template <class T, class Char = char>
+struct is_convertible_to_basic_format_string
+    : std::integral_constant<bool,
+                             std::is_convertible<T, fmt::basic_string_view<Char>>::value ||
+                                 std::is_same<remove_cvref_t<T>, fmt_runtime_string<Char>>::value> {
+};
+
+    #if defined(SPDLOG_WCHAR_FILENAMES) || defined(SPDLOG_WCHAR_TO_UTF8_SUPPORT)
+using wstring_view_t = fmt::basic_string_view<wchar_t>;
+using wmemory_buf_t = fmt::basic_memory_buffer<wchar_t, 250>;
+
+template <typename... Args>
+using wformat_string_t = fmt::wformat_string<Args...>;
+    #endif
+    #define SPDLOG_BUF_TO_STRING(x) fmt::to_string(x)
+#endif
+
 #ifdef SPDLOG_WCHAR_TO_UTF8_SUPPORT
-#ifndef _WIN32
-#error SPDLOG_WCHAR_TO_UTF8_SUPPORT only supported on windows
-#else
-template<typename T>
-struct is_convertible_to_wstring_view : std::is_convertible<T, wstring_view_t>
-{};
-#endif // _WIN32
-#else
-template<typename>
-struct is_convertible_to_wstring_view : std::false_type
-{};
-#endif // SPDLOG_WCHAR_TO_UTF8_SUPPORT
+    #ifndef _WIN32
+        #error SPDLOG_WCHAR_TO_UTF8_SUPPORT only supported on windows
+    #endif  // _WIN32
+#endif      // SPDLOG_WCHAR_TO_UTF8_SUPPORT
+
+template <class T>
+struct is_convertible_to_any_format_string
+    : std::integral_constant<bool,
+                             is_convertible_to_basic_format_string<T, char>::value ||
+                                 is_convertible_to_basic_format_string<T, wchar_t>::value> {};
 
 #if defined(SPDLOG_NO_ATOMIC_LEVELS)
 using level_t = details::null_atomic_int;
@@ -131,13 +237,12 @@ using level_t = std::atomic<int>;
 #define SPDLOG_LEVEL_OFF 6
 
 #if !defined(SPDLOG_ACTIVE_LEVEL)
-#define SPDLOG_ACTIVE_LEVEL SPDLOG_LEVEL_INFO
+    #define SPDLOG_ACTIVE_LEVEL SPDLOG_LEVEL_INFO
 #endif
 
 // Log level enum
 namespace level {
-enum level_enum
-{
+enum level_enum : int {
     trace = SPDLOG_LEVEL_TRACE,
     debug = SPDLOG_LEVEL_DEBUG,
     info = SPDLOG_LEVEL_INFO,
@@ -148,53 +253,53 @@ enum level_enum
     n_levels
 };
 
+#define SPDLOG_LEVEL_NAME_TRACE spdlog::string_view_t("trace", 5)
+#define SPDLOG_LEVEL_NAME_DEBUG spdlog::string_view_t("debug", 5)
+#define SPDLOG_LEVEL_NAME_INFO spdlog::string_view_t("info", 4)
+#define SPDLOG_LEVEL_NAME_WARNING spdlog::string_view_t("warning", 7)
+#define SPDLOG_LEVEL_NAME_ERROR spdlog::string_view_t("error", 5)
+#define SPDLOG_LEVEL_NAME_CRITICAL spdlog::string_view_t("critical", 8)
+#define SPDLOG_LEVEL_NAME_OFF spdlog::string_view_t("off", 3)
+
 #if !defined(SPDLOG_LEVEL_NAMES)
-#define SPDLOG_LEVEL_NAMES                                                                                                                 \
-    {                                                                                                                                      \
-        "trace", "debug", "info", "warning", "error", "critical", "off"                                                                    \
-    }
+    #define SPDLOG_LEVEL_NAMES                                                                  \
+        {                                                                                       \
+            SPDLOG_LEVEL_NAME_TRACE, SPDLOG_LEVEL_NAME_DEBUG, SPDLOG_LEVEL_NAME_INFO,           \
+                SPDLOG_LEVEL_NAME_WARNING, SPDLOG_LEVEL_NAME_ERROR, SPDLOG_LEVEL_NAME_CRITICAL, \
+                SPDLOG_LEVEL_NAME_OFF                                                           \
+        }
 #endif
 
 #if !defined(SPDLOG_SHORT_LEVEL_NAMES)
 
-#define SPDLOG_SHORT_LEVEL_NAMES                                                                                                           \
-    {                                                                                                                                      \
-        "T", "D", "I", "W", "E", "C", "O"                                                                                                  \
-    }
+    #define SPDLOG_SHORT_LEVEL_NAMES \
+        { "T", "D", "I", "W", "E", "C", "O" }
 #endif
 
-SPDLOG_API string_view_t &to_string_view(spdlog::level::level_enum l) SPDLOG_NOEXCEPT;
+SPDLOG_API const string_view_t &to_string_view(spdlog::level::level_enum l) SPDLOG_NOEXCEPT;
 SPDLOG_API const char *to_short_c_str(spdlog::level::level_enum l) SPDLOG_NOEXCEPT;
 SPDLOG_API spdlog::level::level_enum from_str(const std::string &name) SPDLOG_NOEXCEPT;
 
-using level_hasher = std::hash<int>;
-} // namespace level
+}  // namespace level
 
 //
 // Color mode used by sinks with color support.
 //
-enum class color_mode
-{
-    always,
-    automatic,
-    never
-};
+enum class color_mode { always, automatic, never };
 
 //
 // Pattern time - specific time getting to use for pattern_formatter.
 // local time by default
 //
-enum class pattern_time_type
-{
-    local, // log localtime
-    utc    // log utc
+enum class pattern_time_type {
+    local,  // log localtime
+    utc     // log utc
 };
 
 //
 // Log exception
 //
-class SPDLOG_API spdlog_ex : public std::exception
-{
+class SPDLOG_API spdlog_ex : public std::exception {
 public:
     explicit spdlog_ex(std::string msg);
     spdlog_ex(const std::string &msg, int last_errno);
@@ -204,43 +309,98 @@ private:
     std::string msg_;
 };
 
-SPDLOG_API void throw_spdlog_ex(const std::string &msg, int last_errno);
-SPDLOG_API void throw_spdlog_ex(std::string msg);
+[[noreturn]] SPDLOG_API void throw_spdlog_ex(const std::string &msg, int last_errno);
+[[noreturn]] SPDLOG_API void throw_spdlog_ex(std::string msg);
 
-struct source_loc
-{
+struct source_loc {
     SPDLOG_CONSTEXPR source_loc() = default;
     SPDLOG_CONSTEXPR source_loc(const char *filename_in, int line_in, const char *funcname_in)
-        : filename{filename_in}
-        , line{line_in}
-        , funcname{funcname_in}
-    {}
+        : filename{filename_in},
+          line{line_in},
+          funcname{funcname_in} {}
 
-    SPDLOG_CONSTEXPR bool empty() const SPDLOG_NOEXCEPT
-    {
-        return line == 0;
-    }
+    SPDLOG_CONSTEXPR bool empty() const SPDLOG_NOEXCEPT { return line <= 0; }
     const char *filename{nullptr};
     int line{0};
     const char *funcname{nullptr};
 };
 
-namespace details {
-// make_unique support for pre c++14
+struct file_event_handlers {
+    file_event_handlers()
+        : before_open(nullptr),
+          after_open(nullptr),
+          before_close(nullptr),
+          after_close(nullptr) {}
 
-#if __cplusplus >= 201402L // C++14 and beyond
+    std::function<void(const filename_t &filename)> before_open;
+    std::function<void(const filename_t &filename, std::FILE *file_stream)> after_open;
+    std::function<void(const filename_t &filename, std::FILE *file_stream)> before_close;
+    std::function<void(const filename_t &filename)> after_close;
+};
+
+namespace details {
+
+// to_string_view
+
+SPDLOG_CONSTEXPR_FUNC spdlog::string_view_t to_string_view(const memory_buf_t &buf)
+    SPDLOG_NOEXCEPT {
+    return spdlog::string_view_t{buf.data(), buf.size()};
+}
+
+SPDLOG_CONSTEXPR_FUNC spdlog::string_view_t to_string_view(spdlog::string_view_t str)
+    SPDLOG_NOEXCEPT {
+    return str;
+}
+
+#if defined(SPDLOG_WCHAR_FILENAMES) || defined(SPDLOG_WCHAR_TO_UTF8_SUPPORT)
+SPDLOG_CONSTEXPR_FUNC spdlog::wstring_view_t to_string_view(const wmemory_buf_t &buf)
+    SPDLOG_NOEXCEPT {
+    return spdlog::wstring_view_t{buf.data(), buf.size()};
+}
+
+SPDLOG_CONSTEXPR_FUNC spdlog::wstring_view_t to_string_view(spdlog::wstring_view_t str)
+    SPDLOG_NOEXCEPT {
+    return str;
+}
+#endif
+
+#if defined(SPDLOG_USE_STD_FORMAT) && __cpp_lib_format >= 202207L
+template <typename T, typename... Args>
+SPDLOG_CONSTEXPR_FUNC std::basic_string_view<T> to_string_view(
+    std::basic_format_string<T, Args...> fmt) SPDLOG_NOEXCEPT {
+    return fmt.get();
+}
+#endif
+
+// make_unique support for pre c++14
+#if __cplusplus >= 201402L  // C++14 and beyond
+using std::enable_if_t;
 using std::make_unique;
 #else
-template<typename T, typename... Args>
-std::unique_ptr<T> make_unique(Args &&... args)
-{
+template <bool B, class T = void>
+using enable_if_t = typename std::enable_if<B, T>::type;
+
+template <typename T, typename... Args>
+std::unique_ptr<T> make_unique(Args &&...args) {
     static_assert(!std::is_array<T>::value, "arrays not supported");
     return std::unique_ptr<T>(new T(std::forward<Args>(args)...));
 }
 #endif
-} // namespace details
-} // namespace spdlog
+
+// to avoid useless casts (see https://github.com/nlohmann/json/issues/2893#issuecomment-889152324)
+template <typename T, typename U, enable_if_t<!std::is_same<T, U>::value, int> = 0>
+constexpr T conditional_static_cast(U value) {
+    return static_cast<T>(value);
+}
+
+template <typename T, typename U, enable_if_t<std::is_same<T, U>::value, int> = 0>
+constexpr T conditional_static_cast(U value) {
+    return value;
+}
+
+}  // namespace details
+}  // namespace spdlog
 
 #ifdef SPDLOG_HEADER_ONLY
-#include "common-inl.h"
+    #include "common-inl.h"
 #endif

include/spdlog/details/backtracer-inl.h

@@ -4,66 +4,60 @@
 #pragma once
 
 #ifndef SPDLOG_HEADER_ONLY
-#include <spdlog/details/backtracer.h>
+    #include <spdlog/details/backtracer.h>
 #endif
 namespace spdlog {
 namespace details {
-SPDLOG_INLINE backtracer::backtracer(const backtracer &other)
-{
+SPDLOG_INLINE backtracer::backtracer(const backtracer &other) {
     std::lock_guard<std::mutex> lock(other.mutex_);
     enabled_ = other.enabled();
     messages_ = other.messages_;
 }
 
-SPDLOG_INLINE backtracer::backtracer(backtracer &&other) SPDLOG_NOEXCEPT
-{
+SPDLOG_INLINE backtracer::backtracer(backtracer &&other) SPDLOG_NOEXCEPT {
     std::lock_guard<std::mutex> lock(other.mutex_);
     enabled_ = other.enabled();
     messages_ = std::move(other.messages_);
 }
 
-SPDLOG_INLINE backtracer &backtracer::operator=(backtracer other)
-{
+SPDLOG_INLINE backtracer &backtracer::operator=(backtracer other) {
     std::lock_guard<std::mutex> lock(mutex_);
     enabled_ = other.enabled();
     messages_ = std::move(other.messages_);
     return *this;
 }
 
-SPDLOG_INLINE void backtracer::enable(size_t size)
-{
+SPDLOG_INLINE void backtracer::enable(size_t size) {
     std::lock_guard<std::mutex> lock{mutex_};
     enabled_.store(true, std::memory_order_relaxed);
     messages_ = circular_q<log_msg_buffer>{size};
 }
 
-SPDLOG_INLINE void backtracer::disable()
-{
+SPDLOG_INLINE void backtracer::disable() {
     std::lock_guard<std::mutex> lock{mutex_};
     enabled_.store(false, std::memory_order_relaxed);
 }
 
-SPDLOG_INLINE bool backtracer::enabled() const
-{
-    return enabled_.load(std::memory_order_relaxed);
-}
+SPDLOG_INLINE bool backtracer::enabled() const { return enabled_.load(std::memory_order_relaxed); }
 
-SPDLOG_INLINE void backtracer::push_back(const log_msg &msg)
-{
+SPDLOG_INLINE void backtracer::push_back(const log_msg &msg) {
     std::lock_guard<std::mutex> lock{mutex_};
     messages_.push_back(log_msg_buffer{msg});
 }
 
-// pop all items in the q and apply the given fun on each of them.
-SPDLOG_INLINE void backtracer::foreach_pop(std::function<void(const details::log_msg &)> fun)
-{
+SPDLOG_INLINE bool backtracer::empty() const {
     std::lock_guard<std::mutex> lock{mutex_};
-    while (!messages_.empty())
-    {
+    return messages_.empty();
+}
+
+// pop all items in the q and apply the given fun on each of them.
+SPDLOG_INLINE void backtracer::foreach_pop(std::function<void(const details::log_msg &)> fun) {
+    std::lock_guard<std::mutex> lock{mutex_};
+    while (!messages_.empty()) {
         auto &front_msg = messages_.front();
         fun(front_msg);
         messages_.pop_front();
     }
 }
-} // namespace details
-} // namespace spdlog
+}  // namespace details
+}  // namespace spdlog

include/spdlog/details/backtracer.h

@@ -3,20 +3,19 @@
 
 #pragma once
 
-#include <spdlog/details/log_msg_buffer.h>
 #include <spdlog/details/circular_q.h>
+#include <spdlog/details/log_msg_buffer.h>
 
 #include <atomic>
-#include <mutex>
 #include <functional>
+#include <mutex>
 
 // Store log messages in circular buffer.
 // Useful for storing debug data in case of error/warning happens.
 
 namespace spdlog {
 namespace details {
-class SPDLOG_API backtracer
-{
+class SPDLOG_API backtracer {
     mutable std::mutex mutex_;
     std::atomic<bool> enabled_{false};
     circular_q<log_msg_buffer> messages_;
@@ -32,14 +31,15 @@ public:
     void disable();
     bool enabled() const;
     void push_back(const log_msg &msg);
+    bool empty() const;
 
     // pop all items in the q and apply the given fun on each of them.
     void foreach_pop(std::function<void(const details::log_msg &)> fun);
 };
 
-} // namespace details
-} // namespace spdlog
+}  // namespace details
+}  // namespace spdlog
 
 #ifdef SPDLOG_HEADER_ONLY
-#include "backtracer-inl.h"
-#endif
+    #include "backtracer-inl.h"
+#endif

include/spdlog/details/circular_q.h

@@ -4,14 +4,15 @@
 // circular q view of std::vector.
 #pragma once
 
-#include <vector>
 #include <cassert>
+#include <vector>
+
+#include "spdlog/common.h"
 
 namespace spdlog {
 namespace details {
-template<typename T>
-class circular_q
-{
+template <typename T>
+class circular_q {
     size_t max_items_ = 0;
     typename std::vector<T>::size_type head_ = 0;
     typename std::vector<T>::size_type tail_ = 0;
@@ -25,35 +26,29 @@ public:
     circular_q() = default;
 
     explicit circular_q(size_t max_items)
-        : max_items_(max_items + 1) // one item is reserved as marker for full q
-        , v_(max_items_)
-    {}
+        : max_items_(max_items + 1)  // one item is reserved as marker for full q
+          ,
+          v_(max_items_) {}
 
     circular_q(const circular_q &) = default;
     circular_q &operator=(const circular_q &) = default;
 
     // move cannot be default,
     // since we need to reset head_, tail_, etc to zero in the moved object
-    circular_q(circular_q &&other) SPDLOG_NOEXCEPT
-    {
-        copy_moveable(std::move(other));
-    }
+    circular_q(circular_q &&other) SPDLOG_NOEXCEPT { copy_moveable(std::move(other)); }
 
-    circular_q &operator=(circular_q &&other) SPDLOG_NOEXCEPT
-    {
+    circular_q &operator=(circular_q &&other) SPDLOG_NOEXCEPT {
         copy_moveable(std::move(other));
         return *this;
     }
 
     // push back, overrun (oldest) item if no room left
-    void push_back(T &&item)
-    {
-        if (max_items_ > 0)
-        {
+    void push_back(T &&item) {
+        if (max_items_ > 0) {
             v_[tail_] = std::move(item);
             tail_ = (tail_ + 1) % max_items_;
 
-            if (tail_ == head_) // overrun last item if full
+            if (tail_ == head_)  // overrun last item if full
             {
                 head_ = (head_ + 1) % max_items_;
                 ++overrun_counter_;
@@ -63,68 +58,47 @@ public:
 
     // Return reference to the front item.
     // If there are no elements in the container, the behavior is undefined.
-    const T &front() const
-    {
-        return v_[head_];
-    }
+    const T &front() const { return v_[head_]; }
 
-    T &front()
-    {
-        return v_[head_];
-    }
+    T &front() { return v_[head_]; }
 
     // Return number of elements actually stored
-    size_t size() const
-    {
-        if (tail_ >= head_)
-        {
+    size_t size() const {
+        if (tail_ >= head_) {
             return tail_ - head_;
-        }
-        else
-        {
+        } else {
             return max_items_ - (head_ - tail_);
         }
     }
 
     // Return const reference to item by index.
     // If index is out of range 0…size()-1, the behavior is undefined.
-    const T &at(size_t i) const
-    {
+    const T &at(size_t i) const {
         assert(i < size());
         return v_[(head_ + i) % max_items_];
     }
 
     // Pop item from front.
     // If there are no elements in the container, the behavior is undefined.
-    void pop_front()
-    {
-        head_ = (head_ + 1) % max_items_;
-    }
+    void pop_front() { head_ = (head_ + 1) % max_items_; }
 
-    bool empty() const
-    {
-        return tail_ == head_;
-    }
+    bool empty() const { return tail_ == head_; }
 
-    bool full() const
-    {
+    bool full() const {
         // head is ahead of the tail by 1
-        if (max_items_ > 0)
-        {
+        if (max_items_ > 0) {
             return ((tail_ + 1) % max_items_) == head_;
         }
         return false;
     }
 
-    size_t overrun_counter() const
-    {
-        return overrun_counter_;
-    }
+    size_t overrun_counter() const { return overrun_counter_; }
+
+    void reset_overrun_counter() { overrun_counter_ = 0; }
 
 private:
     // copy from other&& and reset it to disabled state
-    void copy_moveable(circular_q &&other) SPDLOG_NOEXCEPT
-    {
+    void copy_moveable(circular_q &&other) SPDLOG_NOEXCEPT {
         max_items_ = other.max_items_;
         head_ = other.head_;
         tail_ = other.tail_;
@@ -137,5 +111,5 @@ private:
         other.overrun_counter_ = 0;
     }
 };
-} // namespace details
-} // namespace spdlog
+}  // namespace details
+}  // namespace spdlog

include/spdlog/details/console_globals.h

@@ -3,30 +3,26 @@
 
 #pragma once
 
-#include <spdlog/details/null_mutex.h>
 #include <mutex>
+#include <spdlog/details/null_mutex.h>
 
 namespace spdlog {
 namespace details {
 
-struct console_mutex
-{
+struct console_mutex {
     using mutex_t = std::mutex;
-    static mutex_t &mutex()
-    {
+    static mutex_t &mutex() {
         static mutex_t s_mutex;
         return s_mutex;
     }
 };
 
-struct console_nullmutex
-{
+struct console_nullmutex {
     using mutex_t = null_mutex;
-    static mutex_t &mutex()
-    {
+    static mutex_t &mutex() {
         static mutex_t s_mutex;
         return s_mutex;
     }
 };
-} // namespace details
-} // namespace spdlog
+}  // namespace details
+}  // namespace spdlog

include/spdlog/details/file_helper-inl.h

@@ -4,94 +4,115 @@
 #pragma once
 
 #ifndef SPDLOG_HEADER_ONLY
-#include <spdlog/details/file_helper.h>
+    #include <spdlog/details/file_helper.h>
 #endif
 
-#include <spdlog/details/os.h>
 #include <spdlog/common.h>
+#include <spdlog/details/os.h>
 
 #include <cerrno>
-#include <chrono>
 #include <cstdio>
 #include <string>
-#include <thread>
 #include <tuple>
 
 namespace spdlog {
 namespace details {
 
-SPDLOG_INLINE file_helper::~file_helper()
-{
-    close();
-}
+SPDLOG_INLINE file_helper::file_helper(const file_event_handlers &event_handlers)
+    : event_handlers_(event_handlers) {}
 
-SPDLOG_INLINE void file_helper::open(const filename_t &fname, bool truncate)
-{
+SPDLOG_INLINE file_helper::~file_helper() { close(); }
+
+SPDLOG_INLINE void file_helper::open(const filename_t &fname, bool truncate) {
     close();
     filename_ = fname;
-    auto *mode = truncate ? SPDLOG_FILENAME_T("wb") : SPDLOG_FILENAME_T("ab");
 
-    for (int tries = 0; tries < open_tries_; ++tries)
-    {
+    auto *mode = SPDLOG_FILENAME_T("ab");
+    auto *trunc_mode = SPDLOG_FILENAME_T("wb");
+
+    if (event_handlers_.before_open) {
+        event_handlers_.before_open(filename_);
+    }
+    for (int tries = 0; tries < open_tries_; ++tries) {
         // create containing folder if not exists already.
         os::create_dir(os::dir_name(fname));
-        if (!os::fopen_s(&fd_, fname, mode))
-        {
+        if (truncate) {
+            // Truncate by opening-and-closing a tmp file in "wb" mode, always
+            // opening the actual log-we-write-to in "ab" mode, since that
+            // interacts more politely with eternal processes that might
+            // rotate/truncate the file underneath us.
+            std::FILE *tmp;
+            if (os::fopen_s(&tmp, fname, trunc_mode)) {
+                continue;
+            }
+            std::fclose(tmp);
+        }
+        if (!os::fopen_s(&fd_, fname, mode)) {
+            if (event_handlers_.after_open) {
+                event_handlers_.after_open(filename_, fd_);
+            }
             return;
         }
 
         details::os::sleep_for_millis(open_interval_);
     }
 
-    throw_spdlog_ex("Failed opening file " + os::filename_to_str(filename_) + " for writing", errno);
+    throw_spdlog_ex("Failed opening file " + os::filename_to_str(filename_) + " for writing",
+                    errno);
 }
 
-SPDLOG_INLINE void file_helper::reopen(bool truncate)
-{
-    if (filename_.empty())
-    {
+SPDLOG_INLINE void file_helper::reopen(bool truncate) {
+    if (filename_.empty()) {
         throw_spdlog_ex("Failed re opening file - was not opened before");
     }
     this->open(filename_, truncate);
 }
 
-SPDLOG_INLINE void file_helper::flush()
-{
-    std::fflush(fd_);
-}
-
-SPDLOG_INLINE void file_helper::close()
-{
-    if (fd_ != nullptr)
-    {
-        std::fclose(fd_);
-        fd_ = nullptr;
+SPDLOG_INLINE void file_helper::flush() {
+    if (std::fflush(fd_) != 0) {
+        throw_spdlog_ex("Failed flush to file " + os::filename_to_str(filename_), errno);
     }
 }
 
-SPDLOG_INLINE void file_helper::write(const memory_buf_t &buf)
-{
+SPDLOG_INLINE void file_helper::sync() {
+    if (!os::fsync(fd_)) {
+        throw_spdlog_ex("Failed to fsync file " + os::filename_to_str(filename_), errno);
+    }
+}
+
+SPDLOG_INLINE void file_helper::close() {
+    if (fd_ != nullptr) {
+        if (event_handlers_.before_close) {
+            event_handlers_.before_close(filename_, fd_);
+        }
+
+        std::fclose(fd_);
+        fd_ = nullptr;
+
+        if (event_handlers_.after_close) {
+            event_handlers_.after_close(filename_);
+        }
+    }
+}
+
+SPDLOG_INLINE void file_helper::write(const memory_buf_t &buf) {
+    if (fd_ == nullptr) return;
     size_t msg_size = buf.size();
     auto data = buf.data();
-    if (std::fwrite(data, 1, msg_size, fd_) != msg_size)
-    {
+
+    if (!details::os::fwrite_bytes(data, msg_size, fd_)) {
         throw_spdlog_ex("Failed writing to file " + os::filename_to_str(filename_), errno);
     }
 }
 
-SPDLOG_INLINE size_t file_helper::size() const
-{
-    if (fd_ == nullptr)
-    {
+SPDLOG_INLINE size_t file_helper::size() const {
+    if (fd_ == nullptr) {
         throw_spdlog_ex("Cannot use size() on closed file " + os::filename_to_str(filename_));
     }
     return os::filesize(fd_);
 }
 
-SPDLOG_INLINE const filename_t &file_helper::filename() const
-{
-    return filename_;
-}
+SPDLOG_INLINE const filename_t &file_helper::filename() const { return filename_; }
 
 //
 // return file path and its extension:
@@ -106,21 +127,19 @@ SPDLOG_INLINE const filename_t &file_helper::filename() const
 // ".mylog" => (".mylog". "")
 // "my_folder/.mylog" => ("my_folder/.mylog", "")
 // "my_folder/.mylog.txt" => ("my_folder/.mylog", ".txt")
-SPDLOG_INLINE std::tuple<filename_t, filename_t> file_helper::split_by_extension(const filename_t &fname)
-{
+SPDLOG_INLINE std::tuple<filename_t, filename_t> file_helper::split_by_extension(
+    const filename_t &fname) {
     auto ext_index = fname.rfind('.');
 
     // no valid extension found - return whole path and empty string as
     // extension
-    if (ext_index == filename_t::npos || ext_index == 0 || ext_index == fname.size() - 1)
-    {
+    if (ext_index == filename_t::npos || ext_index == 0 || ext_index == fname.size() - 1) {
         return std::make_tuple(fname, filename_t());
     }
 
     // treat cases like "/etc/rc.d/somelogfile or "/abc/.hiddenfile"
-    auto folder_index = fname.rfind(details::os::folder_sep);
-    if (folder_index != filename_t::npos && folder_index >= ext_index - 1)
-    {
+    auto folder_index = fname.find_last_of(details::os::folder_seps_filename);
+    if (folder_index != filename_t::npos && folder_index >= ext_index - 1) {
         return std::make_tuple(fname, filename_t());
     }
 
@@ -128,5 +147,5 @@ SPDLOG_INLINE std::tuple<filename_t, filename_t> file_helper::split_by_extension
     return std::make_tuple(fname.substr(0, ext_index), fname.substr(ext_index));
 }
 
-} // namespace details
-} // namespace spdlog
+}  // namespace details
+}  // namespace spdlog

include/spdlog/details/file_helper.h

@@ -13,10 +13,10 @@ namespace details {
 // When failing to open a file, retry several times(5) with a delay interval(10 ms).
 // Throw spdlog_ex exception on errors.
 
-class SPDLOG_API file_helper
-{
+class SPDLOG_API file_helper {
 public:
-    explicit file_helper() = default;
+    file_helper() = default;
+    explicit file_helper(const file_event_handlers &event_handlers);
 
     file_helper(const file_helper &) = delete;
     file_helper &operator=(const file_helper &) = delete;
@@ -25,6 +25,7 @@ public:
     void open(const filename_t &fname, bool truncate = false);
     void reopen(bool truncate);
     void flush();
+    void sync();
     void close();
     void write(const memory_buf_t &buf);
     size_t size() const;
@@ -47,13 +48,14 @@ public:
 
 private:
     const int open_tries_ = 5;
-    const int open_interval_ = 10;
+    const unsigned int open_interval_ = 10;
     std::FILE *fd_{nullptr};
     filename_t filename_;
+    file_event_handlers event_handlers_;
 };
-} // namespace details
-} // namespace spdlog
+}  // namespace details
+}  // namespace spdlog
 
 #ifdef SPDLOG_HEADER_ONLY
-#include "file_helper-inl.h"
+    #include "file_helper-inl.h"
 #endif

include/spdlog/details/fmt_helper.h

@@ -3,99 +3,132 @@
 #pragma once
 
 #include <chrono>
-#include <type_traits>
-#include <spdlog/fmt/fmt.h>
+#include <iterator>
 #include <spdlog/common.h>
+#include <spdlog/fmt/fmt.h>
+#include <type_traits>
+
+#ifdef SPDLOG_USE_STD_FORMAT
+    #include <charconv>
+    #include <limits>
+#endif
 
 // Some fmt helpers to efficiently format and pad ints and strings
 namespace spdlog {
 namespace details {
 namespace fmt_helper {
 
-inline spdlog::string_view_t to_string_view(const memory_buf_t &buf) SPDLOG_NOEXCEPT
-{
-    return spdlog::string_view_t{buf.data(), buf.size()};
-}
-
-inline void append_string_view(spdlog::string_view_t view, memory_buf_t &dest)
-{
+inline void append_string_view(spdlog::string_view_t view, memory_buf_t &dest) {
     auto *buf_ptr = view.data();
     dest.append(buf_ptr, buf_ptr + view.size());
 }
 
-template<typename T>
-inline void append_int(T n, memory_buf_t &dest)
-{
+#ifdef SPDLOG_USE_STD_FORMAT
+template <typename T>
+inline void append_int(T n, memory_buf_t &dest) {
+    // Buffer should be large enough to hold all digits (digits10 + 1) and a sign
+    SPDLOG_CONSTEXPR const auto BUF_SIZE = std::numeric_limits<T>::digits10 + 2;
+    char buf[BUF_SIZE];
+
+    auto [ptr, ec] = std::to_chars(buf, buf + BUF_SIZE, n, 10);
+    if (ec == std::errc()) {
+        dest.append(buf, ptr);
+    } else {
+        throw_spdlog_ex("Failed to format int", static_cast<int>(ec));
+    }
+}
+#else
+template <typename T>
+inline void append_int(T n, memory_buf_t &dest) {
     fmt::format_int i(n);
     dest.append(i.data(), i.data() + i.size());
 }
+#endif
 
-template<typename T>
-inline unsigned int count_digits(T n)
-{
-    using count_type = typename std::conditional<(sizeof(T) > sizeof(uint32_t)), uint64_t, uint32_t>::type;
-    return static_cast<unsigned int>(fmt::internal::count_digits(static_cast<count_type>(n)));
+template <typename T>
+SPDLOG_CONSTEXPR_FUNC unsigned int count_digits_fallback(T n) {
+    // taken from fmt: https://github.com/fmtlib/fmt/blob/8.0.1/include/fmt/format.h#L899-L912
+    unsigned int count = 1;
+    for (;;) {
+        // Integer division is slow so do it for a group of four digits instead
+        // of for every digit. The idea comes from the talk by Alexandrescu
+        // "Three Optimization Tips for C++". See speed-test for a comparison.
+        if (n < 10) return count;
+        if (n < 100) return count + 1;
+        if (n < 1000) return count + 2;
+        if (n < 10000) return count + 3;
+        n /= 10000u;
+        count += 4;
+    }
 }
 
-inline void pad2(int n, memory_buf_t &dest)
-{
-    if (n >= 0 && n < 100) // 0-99
+template <typename T>
+inline unsigned int count_digits(T n) {
+    using count_type =
+        typename std::conditional<(sizeof(T) > sizeof(uint32_t)), uint64_t, uint32_t>::type;
+#ifdef SPDLOG_USE_STD_FORMAT
+    return count_digits_fallback(static_cast<count_type>(n));
+#else
+    return static_cast<unsigned int>(fmt::
+    // fmt 7.0.0 renamed the internal namespace to detail.
+    // See: https://github.com/fmtlib/fmt/issues/1538
+    #if FMT_VERSION < 70000
+                                         internal
+    #else
+                                         detail
+    #endif
+                                     ::count_digits(static_cast<count_type>(n)));
+#endif
+}
+
+inline void pad2(int n, memory_buf_t &dest) {
+    if (n >= 0 && n < 100)  // 0-99
     {
         dest.push_back(static_cast<char>('0' + n / 10));
         dest.push_back(static_cast<char>('0' + n % 10));
-    }
-    else // unlikely, but just in case, let fmt deal with it
+    } else  // unlikely, but just in case, let fmt deal with it
     {
-        fmt::format_to(dest, "{:02}", n);
+        fmt_lib::format_to(std::back_inserter(dest), SPDLOG_FMT_STRING("{:02}"), n);
     }
 }
 
-template<typename T>
-inline void pad_uint(T n, unsigned int width, memory_buf_t &dest)
-{
+template <typename T>
+inline void pad_uint(T n, unsigned int width, memory_buf_t &dest) {
     static_assert(std::is_unsigned<T>::value, "pad_uint must get unsigned T");
-    for (auto digits = count_digits(n); digits < width; digits++)
-    {
+    for (auto digits = count_digits(n); digits < width; digits++) {
         dest.push_back('0');
     }
     append_int(n, dest);
 }
 
-template<typename T>
-inline void pad3(T n, memory_buf_t &dest)
-{
+template <typename T>
+inline void pad3(T n, memory_buf_t &dest) {
     static_assert(std::is_unsigned<T>::value, "pad3 must get unsigned T");
-    if (n < 1000)
-    {
+    if (n < 1000) {
         dest.push_back(static_cast<char>(n / 100 + '0'));
         n = n % 100;
         dest.push_back(static_cast<char>((n / 10) + '0'));
         dest.push_back(static_cast<char>((n % 10) + '0'));
-    }
-    else
-    {
+    } else {
         append_int(n, dest);
     }
 }
 
-template<typename T>
-inline void pad6(T n, memory_buf_t &dest)
-{
+template <typename T>
+inline void pad6(T n, memory_buf_t &dest) {
     pad_uint(n, 6, dest);
 }
 
-template<typename T>
-inline void pad9(T n, memory_buf_t &dest)
-{
+template <typename T>
+inline void pad9(T n, memory_buf_t &dest) {
     pad_uint(n, 9, dest);
 }
 
 // return fraction of a second of the given time_point.
 // e.g.
 // fraction<std::milliseconds>(tp) -> will return the millis part of the second
-template<typename ToDuration>
-inline ToDuration time_fraction(log_clock::time_point tp)
-{
+template <typename ToDuration>
+inline ToDuration time_fraction(log_clock::time_point tp) {
     using std::chrono::duration_cast;
     using std::chrono::seconds;
     auto duration = tp.time_since_epoch();
@@ -103,6 +136,6 @@ inline ToDuration time_fraction(log_clock::time_point tp)
     return duration_cast<ToDuration>(duration) - duration_cast<ToDuration>(secs);
 }
 
-} // namespace fmt_helper
-} // namespace details
-} // namespace spdlog
+}  // namespace fmt_helper
+}  // namespace details
+}  // namespace spdlog

include/spdlog/details/log_msg-inl.h

@@ -4,7 +4,7 @@
 #pragma once
 
 #ifndef SPDLOG_HEADER_ONLY
-#include <spdlog/details/log_msg.h>
+    #include <spdlog/details/log_msg.h>
 #endif
 
 #include <spdlog/details/os.h>
@@ -12,26 +12,33 @@
 namespace spdlog {
 namespace details {
 
-SPDLOG_INLINE log_msg::log_msg(spdlog::log_clock::time_point log_time, spdlog::source_loc loc, string_view_t a_logger_name,
-    spdlog::level::level_enum lvl, spdlog::string_view_t msg)
-    : logger_name(a_logger_name)
-    , level(lvl)
-    , time(log_time)
+SPDLOG_INLINE log_msg::log_msg(spdlog::log_clock::time_point log_time,
+                               spdlog::source_loc loc,
+                               string_view_t a_logger_name,
+                               spdlog::level::level_enum lvl,
+                               spdlog::string_view_t msg)
+    : logger_name(a_logger_name),
+      level(lvl),
+      time(log_time)
 #ifndef SPDLOG_NO_THREAD_ID
-    , thread_id(os::thread_id())
+      ,
+      thread_id(os::thread_id())
 #endif
-    , source(loc)
-    , payload(msg)
-{}
+      ,
+      source(loc),
+      payload(msg) {
+}
 
-SPDLOG_INLINE log_msg::log_msg(
-    spdlog::source_loc loc, string_view_t a_logger_name, spdlog::level::level_enum lvl, spdlog::string_view_t msg)
-    : log_msg(os::now(), loc, a_logger_name, lvl, msg)
-{}
+SPDLOG_INLINE log_msg::log_msg(spdlog::source_loc loc,
+                               string_view_t a_logger_name,
+                               spdlog::level::level_enum lvl,
+                               spdlog::string_view_t msg)
+    : log_msg(os::now(), loc, a_logger_name, lvl, msg) {}
 
-SPDLOG_INLINE log_msg::log_msg(string_view_t a_logger_name, spdlog::level::level_enum lvl, spdlog::string_view_t msg)
-    : log_msg(os::now(), source_loc{}, a_logger_name, lvl, msg)
-{}
+SPDLOG_INLINE log_msg::log_msg(string_view_t a_logger_name,
+                               spdlog::level::level_enum lvl,
+                               spdlog::string_view_t msg)
+    : log_msg(os::now(), source_loc{}, a_logger_name, lvl, msg) {}
 
-} // namespace details
-} // namespace spdlog
+}  // namespace details
+}  // namespace spdlog

include/spdlog/details/log_msg.h

@@ -8,13 +8,17 @@
 
 namespace spdlog {
 namespace details {
-struct SPDLOG_API log_msg
-{
+struct SPDLOG_API log_msg {
     log_msg() = default;
-    log_msg(log_clock::time_point log_time, source_loc loc, string_view_t logger_name, level::level_enum lvl, string_view_t msg);
+    log_msg(log_clock::time_point log_time,
+            source_loc loc,
+            string_view_t logger_name,
+            level::level_enum lvl,
+            string_view_t msg);
     log_msg(source_loc loc, string_view_t logger_name, level::level_enum lvl, string_view_t msg);
     log_msg(string_view_t logger_name, level::level_enum lvl, string_view_t msg);
     log_msg(const log_msg &other) = default;
+    log_msg &operator=(const log_msg &other) = default;
 
     string_view_t logger_name;
     level::level_enum level{level::off};
@@ -28,9 +32,9 @@ struct SPDLOG_API log_msg
     source_loc source;
     string_view_t payload;
 };
-} // namespace details
-} // namespace spdlog
+}  // namespace details
+}  // namespace spdlog
 
 #ifdef SPDLOG_HEADER_ONLY
-#include "log_msg-inl.h"
+    #include "log_msg-inl.h"
 #endif

include/spdlog/details/log_msg_buffer-inl.h

@@ -4,35 +4,33 @@
 #pragma once
 
 #ifndef SPDLOG_HEADER_ONLY
-#include <spdlog/details/log_msg_buffer.h>
+    #include <spdlog/details/log_msg_buffer.h>
 #endif
 
 namespace spdlog {
 namespace details {
 
 SPDLOG_INLINE log_msg_buffer::log_msg_buffer(const log_msg &orig_msg)
-    : log_msg{orig_msg}
-{
+    : log_msg{orig_msg} {
     buffer.append(logger_name.begin(), logger_name.end());
     buffer.append(payload.begin(), payload.end());
     update_string_views();
 }
 
 SPDLOG_INLINE log_msg_buffer::log_msg_buffer(const log_msg_buffer &other)
-    : log_msg{other}
-{
+    : log_msg{other} {
     buffer.append(logger_name.begin(), logger_name.end());
     buffer.append(payload.begin(), payload.end());
     update_string_views();
 }
 
-SPDLOG_INLINE log_msg_buffer::log_msg_buffer(log_msg_buffer &&other) SPDLOG_NOEXCEPT : log_msg{other}, buffer{std::move(other.buffer)}
-{
+SPDLOG_INLINE log_msg_buffer::log_msg_buffer(log_msg_buffer &&other) SPDLOG_NOEXCEPT
+    : log_msg{other},
+      buffer{std::move(other.buffer)} {
     update_string_views();
 }
 
-SPDLOG_INLINE log_msg_buffer &log_msg_buffer::operator=(const log_msg_buffer &other)
-{
+SPDLOG_INLINE log_msg_buffer &log_msg_buffer::operator=(const log_msg_buffer &other) {
     log_msg::operator=(other);
     buffer.clear();
     buffer.append(other.buffer.data(), other.buffer.data() + other.buffer.size());
@@ -40,19 +38,17 @@ SPDLOG_INLINE log_msg_buffer &log_msg_buffer::operator=(const log_msg_buffer &ot
     return *this;
 }
 
-SPDLOG_INLINE log_msg_buffer &log_msg_buffer::operator=(log_msg_buffer &&other) SPDLOG_NOEXCEPT
-{
+SPDLOG_INLINE log_msg_buffer &log_msg_buffer::operator=(log_msg_buffer &&other) SPDLOG_NOEXCEPT {
     log_msg::operator=(other);
     buffer = std::move(other.buffer);
     update_string_views();
     return *this;
 }
 
-SPDLOG_INLINE void log_msg_buffer::update_string_views()
-{
+SPDLOG_INLINE void log_msg_buffer::update_string_views() {
     logger_name = string_view_t{buffer.data(), logger_name.size()};
     payload = string_view_t{buffer.data() + logger_name.size(), payload.size()};
 }
 
-} // namespace details
-} // namespace spdlog
+}  // namespace details
+}  // namespace spdlog

include/spdlog/details/log_msg_buffer.h

@@ -11,8 +11,7 @@ namespace details {
 // Extend log_msg with internal buffer to store its payload.
 // This is needed since log_msg holds string_views that points to stack data.
 
-class SPDLOG_API log_msg_buffer : public log_msg
-{
+class SPDLOG_API log_msg_buffer : public log_msg {
     memory_buf_t buffer;
     void update_string_views();
 
@@ -25,9 +24,9 @@ public:
     log_msg_buffer &operator=(log_msg_buffer &&other) SPDLOG_NOEXCEPT;
 };
 
-} // namespace details
-} // namespace spdlog
+}  // namespace details
+}  // namespace spdlog
 
 #ifdef SPDLOG_HEADER_ONLY
-#include "log_msg_buffer-inl.h"
+    #include "log_msg_buffer-inl.h"
 #endif

include/spdlog/details/mpmc_blocking_q.h

@@ -12,25 +12,23 @@
 
 #include <spdlog/details/circular_q.h>
 
+#include <atomic>
 #include <condition_variable>
 #include <mutex>
 
 namespace spdlog {
 namespace details {
 
-template<typename T>
-class mpmc_blocking_queue
-{
+template <typename T>
+class mpmc_blocking_queue {
 public:
     using item_type = T;
     explicit mpmc_blocking_queue(size_t max_items)
-        : q_(max_items)
-    {}
+        : q_(max_items) {}
 
 #ifndef __MINGW32__
     // try to enqueue and block if no room left
-    void enqueue(T &&item)
-    {
+    void enqueue(T &&item) {
         {
             std::unique_lock<std::mutex> lock(queue_mutex_);
             pop_cv_.wait(lock, [this] { return !this->q_.full(); });
@@ -40,8 +38,7 @@ public:
     }
 
     // enqueue immediately. overrun oldest message in the queue if no room left.
-    void enqueue_nowait(T &&item)
-    {
+    void enqueue_nowait(T &&item) {
         {
             std::unique_lock<std::mutex> lock(queue_mutex_);
             q_.push_back(std::move(item));
@@ -49,14 +46,29 @@ public:
         push_cv_.notify_one();
     }
 
-    // try to dequeue item. if no item found. wait upto timeout and try again
-    // Return true, if succeeded dequeue item, false otherwise
-    bool dequeue_for(T &popped_item, std::chrono::milliseconds wait_duration)
-    {
+    void enqueue_if_have_room(T &&item) {
+        bool pushed = false;
         {
             std::unique_lock<std::mutex> lock(queue_mutex_);
-            if (!push_cv_.wait_for(lock, wait_duration, [this] { return !this->q_.empty(); }))
-            {
+            if (!q_.full()) {
+                q_.push_back(std::move(item));
+                pushed = true;
+            }
+        }
+
+        if (pushed) {
+            push_cv_.notify_one();
+        } else {
+            ++discard_counter_;
+        }
+    }
+
+    // dequeue with a timeout.
+    // Return true, if succeeded dequeue item, false otherwise
+    bool dequeue_for(T &popped_item, std::chrono::milliseconds wait_duration) {
+        {
+            std::unique_lock<std::mutex> lock(queue_mutex_);
+            if (!push_cv_.wait_for(lock, wait_duration, [this] { return !this->q_.empty(); })) {
                 return false;
             }
             popped_item = std::move(q_.front());
@@ -66,13 +78,23 @@ public:
         return true;
     }
 
+    // blocking dequeue without a timeout.
+    void dequeue(T &popped_item) {
+        {
+            std::unique_lock<std::mutex> lock(queue_mutex_);
+            push_cv_.wait(lock, [this] { return !this->q_.empty(); });
+            popped_item = std::move(q_.front());
+            q_.pop_front();
+        }
+        pop_cv_.notify_one();
+    }
+
 #else
     // apparently mingw deadlocks if the mutex is released before cv.notify_one(),
     // so release the mutex at the very end each function.
 
     // try to enqueue and block if no room left
-    void enqueue(T &&item)
-    {
+    void enqueue(T &&item) {
         std::unique_lock<std::mutex> lock(queue_mutex_);
         pop_cv_.wait(lock, [this] { return !this->q_.full(); });
         q_.push_back(std::move(item));
@@ -80,20 +102,32 @@ public:
     }
 
     // enqueue immediately. overrun oldest message in the queue if no room left.
-    void enqueue_nowait(T &&item)
-    {
+    void enqueue_nowait(T &&item) {
         std::unique_lock<std::mutex> lock(queue_mutex_);
         q_.push_back(std::move(item));
         push_cv_.notify_one();
     }
 
-    // try to dequeue item. if no item found. wait upto timeout and try again
-    // Return true, if succeeded dequeue item, false otherwise
-    bool dequeue_for(T &popped_item, std::chrono::milliseconds wait_duration)
-    {
+    void enqueue_if_have_room(T &&item) {
+        bool pushed = false;
         std::unique_lock<std::mutex> lock(queue_mutex_);
-        if (!push_cv_.wait_for(lock, wait_duration, [this] { return !this->q_.empty(); }))
-        {
+        if (!q_.full()) {
+            q_.push_back(std::move(item));
+            pushed = true;
+        }
+
+        if (pushed) {
+            push_cv_.notify_one();
+        } else {
+            ++discard_counter_;
+        }
+    }
+
+    // dequeue with a timeout.
+    // Return true, if succeeded dequeue item, false otherwise
+    bool dequeue_for(T &popped_item, std::chrono::milliseconds wait_duration) {
+        std::unique_lock<std::mutex> lock(queue_mutex_);
+        if (!push_cv_.wait_for(lock, wait_duration, [this] { return !this->q_.empty(); })) {
             return false;
         }
         popped_item = std::move(q_.front());
@@ -102,19 +136,42 @@ public:
         return true;
     }
 
+    // blocking dequeue without a timeout.
+    void dequeue(T &popped_item) {
+        std::unique_lock<std::mutex> lock(queue_mutex_);
+        push_cv_.wait(lock, [this] { return !this->q_.empty(); });
+        popped_item = std::move(q_.front());
+        q_.pop_front();
+        pop_cv_.notify_one();
+    }
+
 #endif
 
-    size_t overrun_counter()
-    {
-        std::unique_lock<std::mutex> lock(queue_mutex_);
+    size_t overrun_counter() {
+        std::lock_guard<std::mutex> lock(queue_mutex_);
         return q_.overrun_counter();
     }
 
+    size_t discard_counter() { return discard_counter_.load(std::memory_order_relaxed); }
+
+    size_t size() {
+        std::lock_guard<std::mutex> lock(queue_mutex_);
+        return q_.size();
+    }
+
+    void reset_overrun_counter() {
+        std::lock_guard<std::mutex> lock(queue_mutex_);
+        q_.reset_overrun_counter();
+    }
+
+    void reset_discard_counter() { discard_counter_.store(0, std::memory_order_relaxed); }
+
 private:
     std::mutex queue_mutex_;
     std::condition_variable push_cv_;
     std::condition_variable pop_cv_;
     spdlog::details::circular_q<T> q_;
+    std::atomic<size_t> discard_counter_{0};
 };
-} // namespace details
-} // namespace spdlog
+}  // namespace details
+}  // namespace spdlog

include/spdlog/details/null_mutex.h

@@ -9,41 +9,27 @@
 
 namespace spdlog {
 namespace details {
-struct null_mutex
-{
+struct null_mutex {
     void lock() const {}
     void unlock() const {}
-    bool try_lock() const
-    {
-        return true;
-    }
 };
 
-struct null_atomic_int
-{
+struct null_atomic_int {
     int value;
     null_atomic_int() = default;
 
     explicit null_atomic_int(int new_value)
-        : value(new_value)
-    {}
+        : value(new_value) {}
 
-    int load(std::memory_order = std::memory_order_relaxed) const
-    {
-        return value;
-    }
+    int load(std::memory_order = std::memory_order_relaxed) const { return value; }
 
-    void store(int new_value, std::memory_order = std::memory_order_relaxed)
-    {
-        value = new_value;
-    }
+    void store(int new_value, std::memory_order = std::memory_order_relaxed) { value = new_value; }
 
-    int exchange(int new_value, std::memory_order = std::memory_order_relaxed)
-    {
+    int exchange(int new_value, std::memory_order = std::memory_order_relaxed) {
         std::swap(new_value, value);
-        return new_value; // return value before the call
+        return new_value;  // return value before the call
     }
 };
 
-} // namespace details
-} // namespace spdlog
+}  // namespace details
+}  // namespace spdlog

include/spdlog/details/os-inl.h

@@ -4,86 +4,88 @@
 #pragma once
 
 #ifndef SPDLOG_HEADER_ONLY
-#include <spdlog/details/os.h>
+    #include <spdlog/details/os.h>
 #endif
 
 #include <spdlog/common.h>
 
 #include <algorithm>
+#include <array>
 #include <chrono>
 #include <cstdio>
 #include <cstdlib>
 #include <cstring>
 #include <ctime>
 #include <string>
-#include <thread>
-#include <array>
 #include <sys/stat.h>
 #include <sys/types.h>
+#include <thread>
 
 #ifdef _WIN32
+    #include <spdlog/details/windows_include.h>
+    #include <fileapi.h>  // for FlushFileBuffers
+    #include <io.h>       // for _get_osfhandle, _isatty, _fileno
+    #include <process.h>  // for _get_pid
 
-#include <io.h>      // _get_osfhandle and _isatty support
-#include <process.h> //  _get_pid support
-#include <spdlog/details/windows_include.h>
+    #ifdef __MINGW32__
+        #include <share.h>
+    #endif
 
-#ifdef __MINGW32__
-#include <share.h>
+    #if defined(SPDLOG_WCHAR_TO_UTF8_SUPPORT) || defined(SPDLOG_WCHAR_FILENAMES)
+        #include <cassert>
+        #include <limits>
+    #endif
+
+    #include <direct.h>  // for _mkdir/_wmkdir
+
+#else  // unix
+
+    #include <fcntl.h>
+    #include <unistd.h>
+
+    #ifdef __linux__
+        #include <sys/syscall.h>  //Use gettid() syscall under linux to get thread id
+
+    #elif defined(_AIX)
+        #include <pthread.h>  // for pthread_getthrds_np
+
+    #elif defined(__DragonFly__) || defined(__FreeBSD__)
+        #include <pthread_np.h>  // for pthread_getthreadid_np
+
+    #elif defined(__NetBSD__)
+        #include <lwp.h>  // for _lwp_self
+
+    #elif defined(__sun)
+        #include <thread.h>  // for thr_self
+    #endif
+
+#endif  // unix
+
+#if defined __APPLE__
+    #include <AvailabilityMacros.h>
 #endif
 
-#if defined(SPDLOG_WCHAR_TO_UTF8_SUPPORT) || defined(SPDLOG_WCHAR_FILENAMES)
-#include <limits>
-#endif
-
-#include <direct.h> // for _mkdir/_wmkdir
-
-#else // unix
-
-#include <fcntl.h>
-#include <unistd.h>
-
-#ifdef __linux__
-#include <sys/syscall.h> //Use gettid() syscall under linux to get thread id
-
-#elif defined(_AIX)
-#include <pthread.h> // for pthread_getthreadid_np
-
-#elif defined(__DragonFly__) || defined(__FreeBSD__)
-#include <pthread_np.h> // for pthread_getthreadid_np
-
-#elif defined(__NetBSD__)
-#include <lwp.h> // for _lwp_self
-
-#elif defined(__sun)
-#include <thread.h> // for thr_self
-#endif
-
-#endif // unix
-
-#ifndef __has_feature      // Clang - feature checking macros.
-#define __has_feature(x) 0 // Compatibility with non-clang compilers.
+#ifndef __has_feature           // Clang - feature checking macros.
+    #define __has_feature(x) 0  // Compatibility with non-clang compilers.
 #endif
 
 namespace spdlog {
 namespace details {
 namespace os {
 
-SPDLOG_INLINE spdlog::log_clock::time_point now() SPDLOG_NOEXCEPT
-{
-
+SPDLOG_INLINE spdlog::log_clock::time_point now() SPDLOG_NOEXCEPT {
 #if defined __linux__ && defined SPDLOG_CLOCK_COARSE
     timespec ts;
     ::clock_gettime(CLOCK_REALTIME_COARSE, &ts);
     return std::chrono::time_point<log_clock, typename log_clock::duration>(
-        std::chrono::duration_cast<typename log_clock::duration>(std::chrono::seconds(ts.tv_sec) + std::chrono::nanoseconds(ts.tv_nsec)));
+        std::chrono::duration_cast<typename log_clock::duration>(
+            std::chrono::seconds(ts.tv_sec) + std::chrono::nanoseconds(ts.tv_nsec)));
 
 #else
     return log_clock::now();
 #endif
 }
-SPDLOG_INLINE std::tm localtime(const std::time_t &time_tt) SPDLOG_NOEXCEPT
-{
-
+SPDLOG_INLINE std::tm localtime(const std::time_t &time_tt) SPDLOG_NOEXCEPT {
 #ifdef _WIN32
     std::tm tm;
     ::localtime_s(&tm, &time_tt);
@@ -94,15 +96,12 @@ SPDLOG_INLINE std::tm localtime(const std::time_t &time_tt) SPDLOG_NOEXCEPT
     return tm;
 }
 
-SPDLOG_INLINE std::tm localtime() SPDLOG_NOEXCEPT
-{
+SPDLOG_INLINE std::tm localtime() SPDLOG_NOEXCEPT {
     std::time_t now_t = ::time(nullptr);
     return localtime(now_t);
 }
 
-SPDLOG_INLINE std::tm gmtime(const std::time_t &time_tt) SPDLOG_NOEXCEPT
-{
-
+SPDLOG_INLINE std::tm gmtime(const std::time_t &time_tt) SPDLOG_NOEXCEPT {
 #ifdef _WIN32
     std::tm tm;
     ::gmtime_s(&tm, &time_tt);
@@ -113,55 +112,49 @@ SPDLOG_INLINE std::tm gmtime(const std::time_t &time_tt) SPDLOG_NOEXCEPT
     return tm;
 }
 
-SPDLOG_INLINE std::tm gmtime() SPDLOG_NOEXCEPT
-{
+SPDLOG_INLINE std::tm gmtime() SPDLOG_NOEXCEPT {
     std::time_t now_t = ::time(nullptr);
     return gmtime(now_t);
 }
 
 // fopen_s on non windows for writing
-SPDLOG_INLINE bool fopen_s(FILE **fp, const filename_t &filename, const filename_t &mode)
-{
+SPDLOG_INLINE bool fopen_s(FILE **fp, const filename_t &filename, const filename_t &mode) {
 #ifdef _WIN32
-#ifdef SPDLOG_WCHAR_FILENAMES
+    #ifdef SPDLOG_WCHAR_FILENAMES
     *fp = ::_wfsopen((filename.c_str()), mode.c_str(), _SH_DENYNO);
-#else
+    #else
     *fp = ::_fsopen((filename.c_str()), mode.c_str(), _SH_DENYNO);
-#endif
-#if defined(SPDLOG_PREVENT_CHILD_FD)
-    if (*fp != nullptr)
-    {
+    #endif
+    #if defined(SPDLOG_PREVENT_CHILD_FD)
+    if (*fp != nullptr) {
         auto file_handle = reinterpret_cast<HANDLE>(_get_osfhandle(::_fileno(*fp)));
-        if (!::SetHandleInformation(file_handle, HANDLE_FLAG_INHERIT, 0))
-        {
+        if (!::SetHandleInformation(file_handle, HANDLE_FLAG_INHERIT, 0)) {
             ::fclose(*fp);
             *fp = nullptr;
         }
     }
-#endif
-#else // unix
-#if defined(SPDLOG_PREVENT_CHILD_FD)
+    #endif
+#else  // unix
+    #if defined(SPDLOG_PREVENT_CHILD_FD)
     const int mode_flag = mode == SPDLOG_FILENAME_T("ab") ? O_APPEND : O_TRUNC;
-    const int fd = ::open((filename.c_str()), O_CREAT | O_WRONLY | O_CLOEXEC | mode_flag, mode_t(0644));
-    if (fd == -1)
-    {
-        return false;
+    const int fd =
+        ::open((filename.c_str()), O_CREAT | O_WRONLY | O_CLOEXEC | mode_flag, mode_t(0644));
+    if (fd == -1) {
+        return true;
     }
     *fp = ::fdopen(fd, mode.c_str());
-    if (*fp == nullptr)
-    {
+    if (*fp == nullptr) {
         ::close(fd);
     }
-#else
+    #else
     *fp = ::fopen((filename.c_str()), mode.c_str());
-#endif
+    #endif
 #endif
 
     return *fp == nullptr;
 }
 
-SPDLOG_INLINE int remove(const filename_t &filename) SPDLOG_NOEXCEPT
-{
+SPDLOG_INLINE int remove(const filename_t &filename) SPDLOG_NOEXCEPT {
 #if defined(_WIN32) && defined(SPDLOG_WCHAR_FILENAMES)
     return ::_wremove(filename.c_str());
 #else
@@ -169,13 +162,11 @@ SPDLOG_INLINE int remove(const filename_t &filename) SPDLOG_NOEXCEPT
 #endif
 }
 
-SPDLOG_INLINE int remove_if_exists(const filename_t &filename) SPDLOG_NOEXCEPT
-{
+SPDLOG_INLINE int remove_if_exists(const filename_t &filename) SPDLOG_NOEXCEPT {
     return path_exists(filename) ? remove(filename) : 0;
 }
 
-SPDLOG_INLINE int rename(const filename_t &filename1, const filename_t &filename2) SPDLOG_NOEXCEPT
-{
+SPDLOG_INLINE int rename(const filename_t &filename1, const filename_t &filename2) SPDLOG_NOEXCEPT {
 #if defined(_WIN32) && defined(SPDLOG_WCHAR_FILENAMES)
     return ::_wrename(filename1.c_str(), filename2.c_str());
 #else
@@ -184,104 +175,104 @@ SPDLOG_INLINE int rename(const filename_t &filename1, const filename_t &filename
 }
 
 // Return true if path exists (file or directory)
-SPDLOG_INLINE bool path_exists(const filename_t &filename) SPDLOG_NOEXCEPT
-{
+SPDLOG_INLINE bool path_exists(const filename_t &filename) SPDLOG_NOEXCEPT {
 #ifdef _WIN32
-#ifdef SPDLOG_WCHAR_FILENAMES
-    auto attribs = ::GetFileAttributesW(filename.c_str());
-#else
-    auto attribs = ::GetFileAttributesA(filename.c_str());
-#endif
-    return attribs != INVALID_FILE_ATTRIBUTES;
-#else // common linux/unix all have the stat system call
+    struct _stat buffer;
+    #ifdef SPDLOG_WCHAR_FILENAMES
+    return (::_wstat(filename.c_str(), &buffer) == 0);
+    #else
+    return (::_stat(filename.c_str(), &buffer) == 0);
+    #endif
+#else  // common linux/unix all have the stat system call
     struct stat buffer;
     return (::stat(filename.c_str(), &buffer) == 0);
 #endif
 }
 
+#ifdef _MSC_VER
+    // avoid warning about unreachable statement at the end of filesize()
+    #pragma warning(push)
+    #pragma warning(disable : 4702)
+#endif
+
 // Return file size according to open FILE* object
-SPDLOG_INLINE size_t filesize(FILE *f)
-{
-    if (f == nullptr)
-    {
+SPDLOG_INLINE size_t filesize(FILE *f) {
+    if (f == nullptr) {
         throw_spdlog_ex("Failed getting file size. fd is null");
     }
 #if defined(_WIN32) && !defined(__CYGWIN__)
     int fd = ::_fileno(f);
-#if _WIN64 // 64 bits
+    #if defined(_WIN64)  // 64 bits
     __int64 ret = ::_filelengthi64(fd);
-    if (ret >= 0)
-    {
+    if (ret >= 0) {
         return static_cast<size_t>(ret);
     }
 
-#else // windows 32 bits
+    #else  // windows 32 bits
     long ret = ::_filelength(fd);
-    if (ret >= 0)
-    {
+    if (ret >= 0) {
         return static_cast<size_t>(ret);
     }
-#endif
+    #endif
 
-#else // unix
-// OpenBSD doesn't compile with :: before the fileno(..)
-#if defined(__OpenBSD__)
+#else  // unix
+    // OpenBSD and AIX doesn't compile with :: before the fileno(..)
+    #if defined(__OpenBSD__) || defined(_AIX)
     int fd = fileno(f);
-#else
+    #else
     int fd = ::fileno(f);
-#endif
-// 64 bits(but not in osx or cygwin, where fstat64 is deprecated)
-#if (defined(__linux__) || defined(__sun) || defined(_AIX)) && (defined(__LP64__) || defined(_LP64))
+    #endif
+    // 64 bits(but not in osx, linux/musl or cygwin, where fstat64 is deprecated)
+    #if ((defined(__linux__) && defined(__GLIBC__)) || defined(__sun) || defined(_AIX)) && \
+        (defined(__LP64__) || defined(_LP64))
     struct stat64 st;
-    if (::fstat64(fd, &st) == 0)
-    {
+    if (::fstat64(fd, &st) == 0) {
         return static_cast<size_t>(st.st_size);
     }
-#else // other unix or linux 32 bits or cygwin
+    #else  // other unix or linux 32 bits or cygwin
     struct stat st;
-    if (::fstat(fd, &st) == 0)
-    {
+    if (::fstat(fd, &st) == 0) {
         return static_cast<size_t>(st.st_size);
     }
-#endif
+    #endif
 #endif
     throw_spdlog_ex("Failed getting file size from fd", errno);
-    return 0; // will not be reached.
+    return 0;  // will not be reached.
 }
 
-// Return utc offset in minutes or throw spdlog_ex on failure
-SPDLOG_INLINE int utc_minutes_offset(const std::tm &tm)
-{
+#ifdef _MSC_VER
+    #pragma warning(pop)
+#endif
 
+// Return utc offset in minutes or throw spdlog_ex on failure
+SPDLOG_INLINE int utc_minutes_offset(const std::tm &tm) {
 #ifdef _WIN32
-#if _WIN32_WINNT < _WIN32_WINNT_WS08
+    #if _WIN32_WINNT < _WIN32_WINNT_WS08
     TIME_ZONE_INFORMATION tzinfo;
     auto rv = ::GetTimeZoneInformation(&tzinfo);
-#else
+    #else
     DYNAMIC_TIME_ZONE_INFORMATION tzinfo;
     auto rv = ::GetDynamicTimeZoneInformation(&tzinfo);
-#endif
-    if (rv == TIME_ZONE_ID_INVALID)
-        throw_spdlog_ex("Failed getting timezone info. ", errno);
+    #endif
+    if (rv == TIME_ZONE_ID_INVALID) throw_spdlog_ex("Failed getting timezone info. ", errno);
 
     int offset = -tzinfo.Bias;
-    if (tm.tm_isdst)
-    {
+    if (tm.tm_isdst) {
         offset -= tzinfo.DaylightBias;
-    }
-    else
-    {
+    } else {
         offset -= tzinfo.StandardBias;
     }
     return offset;
 #else
 
-#if defined(sun) || defined(__sun) || defined(_AIX) || (!defined(_BSD_SOURCE) && !defined(_GNU_SOURCE))
+    #if defined(sun) || defined(__sun) || defined(_AIX) ||                        \
+        (defined(__NEWLIB__) && !defined(__TM_GMTOFF)) ||                         \
+        (!defined(__APPLE__) && !defined(_BSD_SOURCE) && !defined(_GNU_SOURCE) && \
+         (!defined(_POSIX_VERSION) || (_POSIX_VERSION < 202405L)))
     // 'tm_gmtoff' field is BSD extension and it's missing on SunOS/Solaris
-    struct helper
-    {
-        static long int calculate_gmt_offset(const std::tm &localtm = details::os::localtime(), const std::tm &gmtm = details::os::gmtime())
-        {
+    struct helper {
+        static long int calculate_gmt_offset(const std::tm &localtm = details::os::localtime(),
+                                             const std::tm &gmtm = details::os::gmtime()) {
             int local_year = localtm.tm_year + (1900 - 1);
             int gmt_year = gmtm.tm_year + (1900 - 1);
 
@@ -295,7 +286,7 @@ SPDLOG_INLINE int utc_minutes_offset(const std::tm &tm)
                 ((local_year / 100 >> 2) - (gmt_year / 100 >> 2))
 
                 // + difference in years * 365 */
-                + (long int)(local_year - gmt_year) * 365);
+                + static_cast<long int>(local_year - gmt_year) * 365);
 
             long int hours = (24 * days) + (localtm.tm_hour - gmtm.tm_hour);
             long int mins = (60 * hours) + (localtm.tm_min - gmtm.tm_min);
@@ -306,9 +297,9 @@ SPDLOG_INLINE int utc_minutes_offset(const std::tm &tm)
     };
 
     auto offset_seconds = helper::calculate_gmt_offset(tm);
-#else
+    #else
     auto offset_seconds = tm.tm_gmtoff;
-#endif
+    #endif
 
     return static_cast<int>(offset_seconds / 60);
 #endif
@@ -317,16 +308,22 @@ SPDLOG_INLINE int utc_minutes_offset(const std::tm &tm)
 // Return current thread id as size_t
 // It exists because the std::this_thread::get_id() is much slower(especially
 // under VS 2013)
-SPDLOG_INLINE size_t _thread_id() SPDLOG_NOEXCEPT
-{
+SPDLOG_INLINE size_t _thread_id() SPDLOG_NOEXCEPT {
 #ifdef _WIN32
     return static_cast<size_t>(::GetCurrentThreadId());
 #elif defined(__linux__)
-#if defined(__ANDROID__) && defined(__ANDROID_API__) && (__ANDROID_API__ < 21)
-#define SYS_gettid __NR_gettid
-#endif
+    #if defined(__ANDROID__) && defined(__ANDROID_API__) && (__ANDROID_API__ < 21)
+        #define SYS_gettid __NR_gettid
+    #endif
     return static_cast<size_t>(::syscall(SYS_gettid));
-#elif defined(_AIX) || defined(__DragonFly__) || defined(__FreeBSD__)
+#elif defined(_AIX)
+    struct __pthrdsinfo buf;
+    int reg_size = 0;
+    pthread_t pt = pthread_self();
+    int retval = pthread_getthrds_np(&pt, PTHRDSINFO_QUERY_TID, &buf, sizeof(buf), NULL, &reg_size);
+    int tid = (!retval) ? buf.__pi_tid : 0;
+    return static_cast<size_t>(tid);
+#elif defined(__DragonFly__) || defined(__FreeBSD__)
     return static_cast<size_t>(::pthread_getthreadid_np());
 #elif defined(__NetBSD__)
     return static_cast<size_t>(::_lwp_self());
@@ -336,19 +333,36 @@ SPDLOG_INLINE size_t _thread_id() SPDLOG_NOEXCEPT
     return static_cast<size_t>(::thr_self());
 #elif __APPLE__
     uint64_t tid;
+    // There is no pthread_threadid_np prior to Mac OS X 10.6, and it is not supported on any PPC,
+    // including 10.6.8 Rosetta. __POWERPC__ is Apple-specific define encompassing ppc and ppc64.
+    #ifdef MAC_OS_X_VERSION_MAX_ALLOWED
+    {
+        #if (MAC_OS_X_VERSION_MAX_ALLOWED < 1060) || defined(__POWERPC__)
+        tid = pthread_mach_thread_np(pthread_self());
+        #elif MAC_OS_X_VERSION_MIN_REQUIRED < 1060
+        if (&pthread_threadid_np) {
+            pthread_threadid_np(nullptr, &tid);
+        } else {
+            tid = pthread_mach_thread_np(pthread_self());
+        }
+        #else
+        pthread_threadid_np(nullptr, &tid);
+        #endif
+    }
+    #else
     pthread_threadid_np(nullptr, &tid);
+    #endif
     return static_cast<size_t>(tid);
-#else // Default to standard C++11 (other Unix)
+#else  // Default to standard C++11 (other Unix)
     return static_cast<size_t>(std::hash<std::thread::id>()(std::this_thread::get_id()));
 #endif
 }
 
 // Return current thread id as size_t (from thread local storage)
-SPDLOG_INLINE size_t thread_id() SPDLOG_NOEXCEPT
-{
+SPDLOG_INLINE size_t thread_id() SPDLOG_NOEXCEPT {
 #if defined(SPDLOG_NO_TLS)
     return _thread_id();
-#else // cache thread id in tls
+#else  // cache thread id in tls
     static thread_local const size_t tid = _thread_id();
     return tid;
 #endif
@@ -356,8 +370,7 @@ SPDLOG_INLINE size_t thread_id() SPDLOG_NOEXCEPT
 
 // This is avoid msvc issue in sleep_for that happens if the clock changes.
 // See https://github.com/gabime/spdlog/issues/609
-SPDLOG_INLINE void sleep_for_millis(int milliseconds) SPDLOG_NOEXCEPT
-{
+SPDLOG_INLINE void sleep_for_millis(unsigned int milliseconds) SPDLOG_NOEXCEPT {
 #if defined(_WIN32)
     ::Sleep(milliseconds);
 #else
@@ -367,56 +380,57 @@ SPDLOG_INLINE void sleep_for_millis(int milliseconds) SPDLOG_NOEXCEPT
 
 // wchar support for windows file names (SPDLOG_WCHAR_FILENAMES must be defined)
 #if defined(_WIN32) && defined(SPDLOG_WCHAR_FILENAMES)
-SPDLOG_INLINE std::string filename_to_str(const filename_t &filename)
-{
+SPDLOG_INLINE std::string filename_to_str(const filename_t &filename) {
     memory_buf_t buf;
     wstr_to_utf8buf(filename, buf);
-    return fmt::to_string(buf);
+    return SPDLOG_BUF_TO_STRING(buf);
 }
 #else
-SPDLOG_INLINE std::string filename_to_str(const filename_t &filename)
-{
-    return filename;
-}
+SPDLOG_INLINE std::string filename_to_str(const filename_t &filename) { return filename; }
 #endif
 
-SPDLOG_INLINE int pid() SPDLOG_NOEXCEPT
-{
-
+SPDLOG_INLINE int pid() SPDLOG_NOEXCEPT {
 #ifdef _WIN32
-    return static_cast<int>(::GetCurrentProcessId());
+    return conditional_static_cast<int>(::GetCurrentProcessId());
 #else
-    return static_cast<int>(::getpid());
+    return conditional_static_cast<int>(::getpid());
 #endif
 }
 
 // Determine if the terminal supports colors
 // Based on: https://github.com/agauniyal/rang/
-SPDLOG_INLINE bool is_color_terminal() SPDLOG_NOEXCEPT
-{
+SPDLOG_INLINE bool is_color_terminal() SPDLOG_NOEXCEPT {
 #ifdef _WIN32
     return true;
 #else
-    static constexpr std::array<const char *, 14> terms = {
-        {"ansi", "color", "console", "cygwin", "gnome", "konsole", "kterm", "linux", "msys", "putty", "rxvt", "screen", "vt100", "xterm"}};
 
-    const char *env_p = std::getenv("TERM");
-    if (env_p == nullptr)
-    {
-        return false;
-    }
+    static const bool result = []() {
+        const char *env_colorterm_p = std::getenv("COLORTERM");
+        if (env_colorterm_p != nullptr) {
+            return true;
+        }
+
+        static constexpr std::array<const char *, 16> terms = {
+            {"ansi", "color", "console", "cygwin", "gnome", "konsole", "kterm", "linux", "msys",
+             "putty", "rxvt", "screen", "vt100", "xterm", "alacritty", "vt102"}};
+
+        const char *env_term_p = std::getenv("TERM");
+        if (env_term_p == nullptr) {
+            return false;
+        }
+
+        return std::any_of(terms.begin(), terms.end(), [&](const char *term) {
+            return std::strstr(env_term_p, term) != nullptr;
+        });
+    }();
 
-    static const bool result =
-        std::any_of(terms.begin(), terms.end(), [&](const char *term) { return std::strstr(env_p, term) != nullptr; });
     return result;
 #endif
 }
 
 // Determine if the terminal attached
 // Source: https://github.com/agauniyal/rang/
-SPDLOG_INLINE bool in_terminal(FILE *file) SPDLOG_NOEXCEPT
-{
-
+SPDLOG_INLINE bool in_terminal(FILE *file) SPDLOG_NOEXCEPT {
 #ifdef _WIN32
     return ::_isatty(_fileno(file)) != 0;
 #else
@@ -425,51 +439,76 @@ SPDLOG_INLINE bool in_terminal(FILE *file) SPDLOG_NOEXCEPT
 }
 
 #if (defined(SPDLOG_WCHAR_TO_UTF8_SUPPORT) || defined(SPDLOG_WCHAR_FILENAMES)) && defined(_WIN32)
-SPDLOG_INLINE void wstr_to_utf8buf(wstring_view_t wstr, memory_buf_t &target)
-{
-    if (wstr.size() > static_cast<size_t>((std::numeric_limits<int>::max)()))
-    {
+SPDLOG_INLINE void wstr_to_utf8buf(wstring_view_t wstr, memory_buf_t &target) {
+    if (wstr.size() > static_cast<size_t>((std::numeric_limits<int>::max)()) / 4 - 1) {
         throw_spdlog_ex("UTF-16 string is too big to be converted to UTF-8");
     }
 
     int wstr_size = static_cast<int>(wstr.size());
-    if (wstr_size == 0)
-    {
+    if (wstr_size == 0) {
         target.resize(0);
         return;
     }
 
     int result_size = static_cast<int>(target.capacity());
-    if ((wstr_size + 1) * 2 > result_size)
-    {
-        result_size = ::WideCharToMultiByte(CP_UTF8, 0, wstr.data(), wstr_size, NULL, 0, NULL, NULL);
+    if ((wstr_size + 1) * 4 > result_size) {
+        result_size =
+            ::WideCharToMultiByte(CP_UTF8, 0, wstr.data(), wstr_size, NULL, 0, NULL, NULL);
     }
 
-    if (result_size > 0)
-    {
+    if (result_size > 0) {
         target.resize(result_size);
-        result_size = ::WideCharToMultiByte(CP_UTF8, 0, wstr.data(), wstr_size, target.data(), result_size, NULL, NULL);
+        result_size = ::WideCharToMultiByte(CP_UTF8, 0, wstr.data(), wstr_size, target.data(),
+                                            result_size, NULL, NULL);
 
-        if (result_size > 0)
-        {
+        if (result_size > 0) {
             target.resize(result_size);
             return;
         }
     }
 
-    throw_spdlog_ex(fmt::format("WideCharToMultiByte failed. Last error: {}", ::GetLastError()));
+    throw_spdlog_ex(
+        fmt_lib::format("WideCharToMultiByte failed. Last error: {}", ::GetLastError()));
 }
-#endif // (defined(SPDLOG_WCHAR_TO_UTF8_SUPPORT) || defined(SPDLOG_WCHAR_FILENAMES)) && defined(_WIN32)
+
+SPDLOG_INLINE void utf8_to_wstrbuf(string_view_t str, wmemory_buf_t &target) {
+    if (str.size() > static_cast<size_t>((std::numeric_limits<int>::max)()) - 1) {
+        throw_spdlog_ex("UTF-8 string is too big to be converted to UTF-16");
+    }
+
+    int str_size = static_cast<int>(str.size());
+    if (str_size == 0) {
+        target.resize(0);
+        return;
+    }
+
+    // find the size to allocate for the result buffer
+    int result_size = ::MultiByteToWideChar(CP_UTF8, 0, str.data(), str_size, NULL, 0);
+
+    if (result_size > 0) {
+        target.resize(result_size);
+        result_size =
+            ::MultiByteToWideChar(CP_UTF8, 0, str.data(), str_size, target.data(), result_size);
+        if (result_size > 0) {
+            assert(result_size == target.size());
+            return;
+        }
+    }
+
+    throw_spdlog_ex(
+        fmt_lib::format("MultiByteToWideChar failed. Last error: {}", ::GetLastError()));
+}
+#endif  // (defined(SPDLOG_WCHAR_TO_UTF8_SUPPORT) || defined(SPDLOG_WCHAR_FILENAMES)) &&
+        // defined(_WIN32)
 
 // return true on success
-static SPDLOG_INLINE bool mkdir_(const filename_t &path)
-{
+static SPDLOG_INLINE bool mkdir_(const filename_t &path) {
 #ifdef _WIN32
-#ifdef SPDLOG_WCHAR_FILENAMES
+    #ifdef SPDLOG_WCHAR_FILENAMES
     return ::_wmkdir(path.c_str()) == 0;
-#else
+    #else
     return ::_mkdir(path.c_str()) == 0;
-#endif
+    #endif
 #else
     return ::mkdir(path.c_str(), mode_t(0755)) == 0;
 #endif
@@ -477,38 +516,36 @@ static SPDLOG_INLINE bool mkdir_(const filename_t &path)
 
 // create the given directory - and all directories leading to it
 // return true on success or if the directory already exists
-SPDLOG_INLINE bool create_dir(filename_t path)
-{
-    if (path_exists(path))
-    {
+SPDLOG_INLINE bool create_dir(const filename_t &path) {
+    if (path_exists(path)) {
         return true;
     }
 
-    if (path.empty())
-    {
+    if (path.empty()) {
         return false;
     }
 
-#ifdef _WIN32
-    // support forward slash in windows
-    std::replace(path.begin(), path.end(), '/', folder_sep);
-#endif
-
     size_t search_offset = 0;
-    do
-    {
-        auto token_pos = path.find(folder_sep, search_offset);
+    do {
+        auto token_pos = path.find_first_of(folder_seps_filename, search_offset);
         // treat the entire path as a folder if no folder separator not found
-        if (token_pos == filename_t::npos)
-        {
+        if (token_pos == filename_t::npos) {
             token_pos = path.size();
         }
 
         auto subdir = path.substr(0, token_pos);
+#ifdef _WIN32
+        // if subdir is just a drive letter, add a slash e.g. "c:"=>"c:\",
+        // otherwise path_exists(subdir) returns false (issue #3079)
+        const bool is_drive = subdir.length() == 2 && subdir[1] == ':';
+        if (is_drive) {
+            subdir += '\\';
+            token_pos++;
+        }
+#endif
 
-        if (!subdir.empty() && !path_exists(subdir) && !mkdir_(subdir))
-        {
-            return false; // return error if failed creating dir
+        if (!subdir.empty() && !path_exists(subdir) && !mkdir_(subdir)) {
+            return false;  // return error if failed creating dir
         }
         search_offset = token_pos + 1;
     } while (search_offset < path.size());
@@ -521,34 +558,49 @@ SPDLOG_INLINE bool create_dir(filename_t path)
 // "abc/" => "abc"
 // "abc" => ""
 // "abc///" => "abc//"
-SPDLOG_INLINE filename_t dir_name(filename_t path)
-{
-#ifdef _WIN32
-    // support forward slash in windows
-    std::replace(path.begin(), path.end(), '/', folder_sep);
-#endif
-    auto pos = path.find_last_of(folder_sep);
+SPDLOG_INLINE filename_t dir_name(const filename_t &path) {
+    auto pos = path.find_last_of(folder_seps_filename);
     return pos != filename_t::npos ? path.substr(0, pos) : filename_t{};
 }
 
-std::string SPDLOG_INLINE getenv(const char *field)
-{
-
-#if defined(_MSC_VER)
-#if defined(__cplusplus_winrt)
-    return std::string{}; // not supported under uwp
+#ifdef _MSC_VER
+    #pragma warning(push)
+    #pragma warning(disable : 4996)
+#endif  // _MSC_VER
+std::string SPDLOG_INLINE getenv(const char *field) {
+#if defined(_MSC_VER) && defined(__cplusplus_winrt)
+    return std::string{};  // not supported under uwp
 #else
-    size_t len = 0;
-    char buf[128];
-    bool ok = ::getenv_s(&len, buf, sizeof(buf), field) == 0;
-    return ok ? buf : std::string{};
-#endif
-#else // revert to getenv
-    char *buf = ::getenv(field);
+    char *buf = std::getenv(field);
     return buf ? buf : std::string{};
 #endif
 }
+#ifdef _MSC_VER
+    #pragma warning(pop)
+#endif  // _MSC_VER
 
-} // namespace os
-} // namespace details
-} // namespace spdlog
+// Do fsync by FILE handlerpointer
+// Return true on success
+SPDLOG_INLINE bool fsync(FILE *fp) {
+#ifdef _WIN32
+    return FlushFileBuffers(reinterpret_cast<HANDLE>(_get_osfhandle(_fileno(fp)))) != 0;
+#else
+    return ::fsync(fileno(fp)) == 0;
+#endif
+}
+
+// Do non-locking fwrite if possible by the os or use the regular locking fwrite
+// Return true on success.
+SPDLOG_INLINE bool fwrite_bytes(const void *ptr, const size_t n_bytes, FILE *fp) {
+#if defined(_WIN32) && defined(SPDLOG_FWRITE_UNLOCKED)
+    return _fwrite_nolock(ptr, 1, n_bytes, fp) == n_bytes;
+#elif defined(SPDLOG_FWRITE_UNLOCKED)
+    return ::fwrite_unlocked(ptr, 1, n_bytes, fp) == n_bytes;
+#else
+    return std::fwrite(ptr, 1, n_bytes, fp) == n_bytes;
+#endif
+}
+
+}  // namespace os
+}  // namespace details
+}  // namespace spdlog

include/spdlog/details/os.h

@@ -3,8 +3,8 @@
 
 #pragma once
 
+#include <ctime>  // std::time_t
 #include <spdlog/common.h>
-#include <ctime> // std::time_t
 
 namespace spdlog {
 namespace details {
@@ -22,22 +22,28 @@ SPDLOG_API std::tm gmtime() SPDLOG_NOEXCEPT;
 
 // eol definition
 #if !defined(SPDLOG_EOL)
-#ifdef _WIN32
-#define SPDLOG_EOL "\r\n"
-#else
-#define SPDLOG_EOL "\n"
-#endif
+    #ifdef _WIN32
+        #define SPDLOG_EOL "\r\n"
+    #else
+        #define SPDLOG_EOL "\n"
+    #endif
 #endif
 
 SPDLOG_CONSTEXPR static const char *default_eol = SPDLOG_EOL;
 
 // folder separator
-#ifdef _WIN32
-static const char folder_sep = '\\';
-#else
-SPDLOG_CONSTEXPR static const char folder_sep = '/';
+#if !defined(SPDLOG_FOLDER_SEPS)
+    #ifdef _WIN32
+        #define SPDLOG_FOLDER_SEPS "\\/"
+    #else
+        #define SPDLOG_FOLDER_SEPS "/"
+    #endif
 #endif
 
+SPDLOG_CONSTEXPR static const char folder_seps[] = SPDLOG_FOLDER_SEPS;
+SPDLOG_CONSTEXPR static const filename_t::value_type folder_seps_filename[] =
+    SPDLOG_FILENAME_T(SPDLOG_FOLDER_SEPS);
+
 // fopen_s on non windows for writing
 SPDLOG_API bool fopen_s(FILE **fp, const filename_t &filename, const filename_t &mode);
 
@@ -69,7 +75,7 @@ SPDLOG_API size_t thread_id() SPDLOG_NOEXCEPT;
 
 // This is avoid msvc issue in sleep_for that happens if the clock changes.
 // See https://github.com/gabime/spdlog/issues/609
-SPDLOG_API void sleep_for_millis(int milliseconds) SPDLOG_NOEXCEPT;
+SPDLOG_API void sleep_for_millis(unsigned int milliseconds) SPDLOG_NOEXCEPT;
 
 SPDLOG_API std::string filename_to_str(const filename_t &filename);
 
@@ -85,6 +91,8 @@ SPDLOG_API bool in_terminal(FILE *file) SPDLOG_NOEXCEPT;
 
 #if (defined(SPDLOG_WCHAR_TO_UTF8_SUPPORT) || defined(SPDLOG_WCHAR_FILENAMES)) && defined(_WIN32)
 SPDLOG_API void wstr_to_utf8buf(wstring_view_t wstr, memory_buf_t &target);
+
+SPDLOG_API void utf8_to_wstrbuf(string_view_t str, wmemory_buf_t &target);
 #endif
 
 // Return directory name from given path or empty string
@@ -92,20 +100,28 @@ SPDLOG_API void wstr_to_utf8buf(wstring_view_t wstr, memory_buf_t &target);
 // "abc/" => "abc"
 // "abc" => ""
 // "abc///" => "abc//"
-SPDLOG_API filename_t dir_name(filename_t path);
+SPDLOG_API filename_t dir_name(const filename_t &path);
 
 // Create a dir from the given path.
 // Return true if succeeded or if this dir already exists.
-SPDLOG_API bool create_dir(filename_t path);
+SPDLOG_API bool create_dir(const filename_t &path);
 
 // non thread safe, cross platform getenv/getenv_s
 // return empty string if field not found
 SPDLOG_API std::string getenv(const char *field);
 
-} // namespace os
-} // namespace details
-} // namespace spdlog
+// Do fsync by FILE objectpointer.
+// Return true on success.
+SPDLOG_API bool fsync(FILE *fp);
+
+// Do non-locking fwrite if possible by the os or use the regular locking fwrite
+// Return true on success.
+SPDLOG_API bool fwrite_bytes(const void *ptr, const size_t n_bytes, FILE *fp);
+
+}  // namespace os
+}  // namespace details
+}  // namespace spdlog
 
 #ifdef SPDLOG_HEADER_ONLY
-#include "os-inl.h"
+    #include "os-inl.h"
 #endif

include/spdlog/details/periodic_worker-inl.h

@@ -4,38 +4,15 @@
 #pragma once
 
 #ifndef SPDLOG_HEADER_ONLY
-#include <spdlog/details/periodic_worker.h>
+    #include <spdlog/details/periodic_worker.h>
 #endif
 
 namespace spdlog {
 namespace details {
 
-SPDLOG_INLINE periodic_worker::periodic_worker(const std::function<void()> &callback_fun, std::chrono::seconds interval)
-{
-    active_ = (interval > std::chrono::seconds::zero());
-    if (!active_)
-    {
-        return;
-    }
-
-    worker_thread_ = std::thread([this, callback_fun, interval]() {
-        for (;;)
-        {
-            std::unique_lock<std::mutex> lock(this->mutex_);
-            if (this->cv_.wait_for(lock, interval, [this] { return !this->active_; }))
-            {
-                return; // active_ == false, so exit this thread
-            }
-            callback_fun();
-        }
-    });
-}
-
 // stop the worker thread and join it
-SPDLOG_INLINE periodic_worker::~periodic_worker()
-{
-    if (worker_thread_.joinable())
-    {
+SPDLOG_INLINE periodic_worker::~periodic_worker() {
+    if (worker_thread_.joinable()) {
         {
             std::lock_guard<std::mutex> lock(mutex_);
             active_ = false;
@@ -45,5 +22,5 @@ SPDLOG_INLINE periodic_worker::~periodic_worker()
     }
 }
 
-} // namespace details
-} // namespace spdlog
+}  // namespace details
+}  // namespace spdlog

include/spdlog/details/periodic_worker.h

@@ -7,7 +7,8 @@
 //
 // RAII over the owned thread:
 //    creates the thread on construction.
-//    stops and joins the thread on destruction (if the thread is executing a callback, wait for it to finish first).
+//    stops and joins the thread on destruction (if the thread is executing a callback, wait for it
+//    to finish first).
 
 #include <chrono>
 #include <condition_variable>
@@ -17,10 +18,27 @@
 namespace spdlog {
 namespace details {
 
-class SPDLOG_API periodic_worker
-{
+class SPDLOG_API periodic_worker {
 public:
-    periodic_worker(const std::function<void()> &callback_fun, std::chrono::seconds interval);
+    template <typename Rep, typename Period>
+    periodic_worker(const std::function<void()> &callback_fun,
+                    std::chrono::duration<Rep, Period> interval) {
+        active_ = (interval > std::chrono::duration<Rep, Period>::zero());
+        if (!active_) {
+            return;
+        }
+
+        worker_thread_ = std::thread([this, callback_fun, interval]() {
+            for (;;) {
+                std::unique_lock<std::mutex> lock(this->mutex_);
+                if (this->cv_.wait_for(lock, interval, [this] { return !this->active_; })) {
+                    return;  // active_ == false, so exit this thread
+                }
+                callback_fun();
+            }
+        });
+    }
+    std::thread &get_thread() { return worker_thread_; }
     periodic_worker(const periodic_worker &) = delete;
     periodic_worker &operator=(const periodic_worker &) = delete;
     // stop the worker thread and join it
@@ -32,9 +50,9 @@ private:
     std::mutex mutex_;
     std::condition_variable cv_;
 };
-} // namespace details
-} // namespace spdlog
+}  // namespace details
+}  // namespace spdlog
 
 #ifdef SPDLOG_HEADER_ONLY
-#include "periodic_worker-inl.h"
+    #include "periodic_worker-inl.h"
 #endif

include/spdlog/details/registry-inl.h

@@ -4,7 +4,7 @@
 #pragma once
 
 #ifndef SPDLOG_HEADER_ONLY
-#include <spdlog/details/registry.h>
+    #include <spdlog/details/registry.h>
 #endif
 
 #include <spdlog/common.h>
@@ -13,13 +13,13 @@
 #include <spdlog/pattern_formatter.h>
 
 #ifndef SPDLOG_DISABLE_DEFAULT_LOGGER
-// support for the default stdout color logger
-#ifdef _WIN32
-#include <spdlog/sinks/wincolor_sink.h>
-#else
-#include <spdlog/sinks/ansicolor_sink.h>
-#endif
-#endif // SPDLOG_DISABLE_DEFAULT_LOGGER
+    // support for the default stdout color logger
+    #ifdef _WIN32
+        #include <spdlog/sinks/wincolor_sink.h>
+    #else
+        #include <spdlog/sinks/ansicolor_sink.h>
+    #endif
+#endif  // SPDLOG_DISABLE_DEFAULT_LOGGER
 
 #include <chrono>
 #include <functional>
@@ -31,65 +31,65 @@ namespace spdlog {
 namespace details {
 
 SPDLOG_INLINE registry::registry()
-    : formatter_(new pattern_formatter())
-{
-
+    : formatter_(new pattern_formatter()) {
 #ifndef SPDLOG_DISABLE_DEFAULT_LOGGER
     // create default logger (ansicolor_stdout_sink_mt or wincolor_stdout_sink_mt in windows).
-#ifdef _WIN32
+    #ifdef _WIN32
     auto color_sink = std::make_shared<sinks::wincolor_stdout_sink_mt>();
-#else
+    #else
     auto color_sink = std::make_shared<sinks::ansicolor_stdout_sink_mt>();
-#endif
+    #endif
 
     const char *default_logger_name = "";
     default_logger_ = std::make_shared<spdlog::logger>(default_logger_name, std::move(color_sink));
     loggers_[default_logger_name] = default_logger_;
 
-#endif // SPDLOG_DISABLE_DEFAULT_LOGGER
+#endif  // SPDLOG_DISABLE_DEFAULT_LOGGER
 }
 
 SPDLOG_INLINE registry::~registry() = default;
 
-SPDLOG_INLINE void registry::register_logger(std::shared_ptr<logger> new_logger)
-{
+SPDLOG_INLINE void registry::register_logger(std::shared_ptr<logger> new_logger) {
     std::lock_guard<std::mutex> lock(logger_map_mutex_);
     register_logger_(std::move(new_logger));
 }
 
-SPDLOG_INLINE void registry::initialize_logger(std::shared_ptr<logger> new_logger)
-{
+SPDLOG_INLINE void registry::register_or_replace(std::shared_ptr<logger> new_logger) {
+    std::lock_guard<std::mutex> lock(logger_map_mutex_);
+    register_or_replace_(std::move(new_logger));
+}
+
+SPDLOG_INLINE void registry::initialize_logger(std::shared_ptr<logger> new_logger) {
     std::lock_guard<std::mutex> lock(logger_map_mutex_);
     new_logger->set_formatter(formatter_->clone());
 
-    if (err_handler_)
-    {
+    if (err_handler_) {
         new_logger->set_error_handler(err_handler_);
     }
 
-    new_logger->set_level(levels_.get(new_logger->name()));
+    // set new level according to previously configured level or default level
+    auto it = log_levels_.find(new_logger->name());
+    auto new_level = it != log_levels_.end() ? it->second : global_log_level_;
+    new_logger->set_level(new_level);
+
     new_logger->flush_on(flush_level_);
 
-    if (backtrace_n_messages_ > 0)
-    {
+    if (backtrace_n_messages_ > 0) {
         new_logger->enable_backtrace(backtrace_n_messages_);
     }
 
-    if (automatic_registration_)
-    {
+    if (automatic_registration_) {
         register_logger_(std::move(new_logger));
     }
 }
 
-SPDLOG_INLINE std::shared_ptr<logger> registry::get(const std::string &logger_name)
-{
+SPDLOG_INLINE std::shared_ptr<logger> registry::get(const std::string &logger_name) {
     std::lock_guard<std::mutex> lock(logger_map_mutex_);
     auto found = loggers_.find(logger_name);
     return found == loggers_.end() ? nullptr : found->second;
 }
 
-SPDLOG_INLINE std::shared_ptr<logger> registry::default_logger()
-{
+SPDLOG_INLINE std::shared_ptr<logger> registry::default_logger() {
     std::lock_guard<std::mutex> lock(logger_map_mutex_);
     return default_logger_;
 }
@@ -98,147 +98,110 @@ SPDLOG_INLINE std::shared_ptr<logger> registry::default_logger()
 // To be used directly by the spdlog default api (e.g. spdlog::info)
 // This make the default API faster, but cannot be used concurrently with set_default_logger().
 // e.g do not call set_default_logger() from one thread while calling spdlog::info() from another.
-SPDLOG_INLINE logger *registry::get_default_raw()
-{
-    return default_logger_.get();
-}
+SPDLOG_INLINE logger *registry::get_default_raw() { return default_logger_.get(); }
 
 // set default logger.
-// default logger is stored in default_logger_ (for faster retrieval) and in the loggers_ map.
-SPDLOG_INLINE void registry::set_default_logger(std::shared_ptr<logger> new_default_logger)
-{
+// the default logger is stored in default_logger_ (for faster retrieval) and in the loggers_ map.
+SPDLOG_INLINE void registry::set_default_logger(std::shared_ptr<logger> new_default_logger) {
     std::lock_guard<std::mutex> lock(logger_map_mutex_);
-    // remove previous default logger from the map
-    if (default_logger_ != nullptr)
-    {
-        loggers_.erase(default_logger_->name());
-    }
-    if (new_default_logger != nullptr)
-    {
+    if (new_default_logger != nullptr) {
         loggers_[new_default_logger->name()] = new_default_logger;
     }
     default_logger_ = std::move(new_default_logger);
 }
 
-SPDLOG_INLINE void registry::set_tp(std::shared_ptr<thread_pool> tp)
-{
+SPDLOG_INLINE void registry::set_tp(std::shared_ptr<thread_pool> tp) {
     std::lock_guard<std::recursive_mutex> lock(tp_mutex_);
     tp_ = std::move(tp);
 }
 
-SPDLOG_INLINE std::shared_ptr<thread_pool> registry::get_tp()
-{
+SPDLOG_INLINE std::shared_ptr<thread_pool> registry::get_tp() {
     std::lock_guard<std::recursive_mutex> lock(tp_mutex_);
     return tp_;
 }
 
 // Set global formatter. Each sink in each logger will get a clone of this object
-SPDLOG_INLINE void registry::set_formatter(std::unique_ptr<formatter> formatter)
-{
+SPDLOG_INLINE void registry::set_formatter(std::unique_ptr<formatter> formatter) {
     std::lock_guard<std::mutex> lock(logger_map_mutex_);
     formatter_ = std::move(formatter);
-    for (auto &l : loggers_)
-    {
+    for (auto &l : loggers_) {
         l.second->set_formatter(formatter_->clone());
     }
 }
 
-SPDLOG_INLINE void registry::enable_backtrace(size_t n_messages)
-{
+SPDLOG_INLINE void registry::enable_backtrace(size_t n_messages) {
     std::lock_guard<std::mutex> lock(logger_map_mutex_);
     backtrace_n_messages_ = n_messages;
 
-    for (auto &l : loggers_)
-    {
+    for (auto &l : loggers_) {
         l.second->enable_backtrace(n_messages);
     }
 }
 
-SPDLOG_INLINE void registry::disable_backtrace()
-{
+SPDLOG_INLINE void registry::disable_backtrace() {
     std::lock_guard<std::mutex> lock(logger_map_mutex_);
     backtrace_n_messages_ = 0;
-    for (auto &l : loggers_)
-    {
+    for (auto &l : loggers_) {
         l.second->disable_backtrace();
     }
 }
 
-SPDLOG_INLINE void registry::set_level(level::level_enum log_level)
-{
+SPDLOG_INLINE void registry::set_level(level::level_enum log_level) {
     std::lock_guard<std::mutex> lock(logger_map_mutex_);
-    for (auto &l : loggers_)
-    {
+    for (auto &l : loggers_) {
         l.second->set_level(log_level);
     }
-    levels_.set_default(log_level);
+    global_log_level_ = log_level;
 }
 
-SPDLOG_INLINE void registry::flush_on(level::level_enum log_level)
-{
+SPDLOG_INLINE void registry::flush_on(level::level_enum log_level) {
     std::lock_guard<std::mutex> lock(logger_map_mutex_);
-    for (auto &l : loggers_)
-    {
+    for (auto &l : loggers_) {
         l.second->flush_on(log_level);
     }
     flush_level_ = log_level;
 }
 
-SPDLOG_INLINE void registry::flush_every(std::chrono::seconds interval)
-{
-    std::lock_guard<std::mutex> lock(flusher_mutex_);
-    auto clbk = [this]() { this->flush_all(); };
-    periodic_flusher_ = details::make_unique<periodic_worker>(clbk, interval);
-}
-
-SPDLOG_INLINE void registry::set_error_handler(void (*handler)(const std::string &msg))
-{
+SPDLOG_INLINE void registry::set_error_handler(err_handler handler) {
     std::lock_guard<std::mutex> lock(logger_map_mutex_);
-    for (auto &l : loggers_)
-    {
+    for (auto &l : loggers_) {
         l.second->set_error_handler(handler);
     }
-    err_handler_ = handler;
+    err_handler_ = std::move(handler);
 }
 
-SPDLOG_INLINE void registry::apply_all(const std::function<void(const std::shared_ptr<logger>)> &fun)
-{
+SPDLOG_INLINE void registry::apply_all(
+    const std::function<void(const std::shared_ptr<logger>)> &fun) {
     std::lock_guard<std::mutex> lock(logger_map_mutex_);
-    for (auto &l : loggers_)
-    {
+    for (auto &l : loggers_) {
         fun(l.second);
     }
 }
 
-SPDLOG_INLINE void registry::flush_all()
-{
+SPDLOG_INLINE void registry::flush_all() {
     std::lock_guard<std::mutex> lock(logger_map_mutex_);
-    for (auto &l : loggers_)
-    {
+    for (auto &l : loggers_) {
         l.second->flush();
     }
 }
 
-SPDLOG_INLINE void registry::drop(const std::string &logger_name)
-{
+SPDLOG_INLINE void registry::drop(const std::string &logger_name) {
     std::lock_guard<std::mutex> lock(logger_map_mutex_);
+    auto is_default_logger = default_logger_ && default_logger_->name() == logger_name;
     loggers_.erase(logger_name);
-    if (default_logger_ && default_logger_->name() == logger_name)
-    {
+    if (is_default_logger) {
         default_logger_.reset();
     }
 }
 
-SPDLOG_INLINE void registry::drop_all()
-{
+SPDLOG_INLINE void registry::drop_all() {
     std::lock_guard<std::mutex> lock(logger_map_mutex_);
     loggers_.clear();
     default_logger_.reset();
 }
 
 // clean all resources and threads started by the registry
-SPDLOG_INLINE void registry::shutdown()
-{
+SPDLOG_INLINE void registry::shutdown() {
     {
         std::lock_guard<std::mutex> lock(flusher_mutex_);
         periodic_flusher_.reset();
@@ -252,48 +215,56 @@ SPDLOG_INLINE void registry::shutdown()
     }
 }
 
-SPDLOG_INLINE std::recursive_mutex &registry::tp_mutex()
-{
-    return tp_mutex_;
-}
+SPDLOG_INLINE std::recursive_mutex &registry::tp_mutex() { return tp_mutex_; }
 
-SPDLOG_INLINE void registry::set_automatic_registration(bool automatic_registration)
-{
+SPDLOG_INLINE void registry::set_automatic_registration(bool automatic_registration) {
     std::lock_guard<std::mutex> lock(logger_map_mutex_);
     automatic_registration_ = automatic_registration;
 }
 
-SPDLOG_INLINE void registry::update_levels(cfg::log_levels levels)
-{
+SPDLOG_INLINE void registry::set_levels(log_levels levels, level::level_enum *global_level) {
     std::lock_guard<std::mutex> lock(logger_map_mutex_);
-    levels_ = std::move(levels);
-    for (auto &l : loggers_)
-    {
-        auto &logger = l.second;
-        logger->set_level(levels_.get(logger->name()));
+    log_levels_ = std::move(levels);
+    auto global_level_requested = global_level != nullptr;
+    global_log_level_ = global_level_requested ? *global_level : global_log_level_;
+
+    for (auto &logger : loggers_) {
+        auto logger_entry = log_levels_.find(logger.first);
+        if (logger_entry != log_levels_.end()) {
+            logger.second->set_level(logger_entry->second);
+        } else if (global_level_requested) {
+            logger.second->set_level(*global_level);
+        }
     }
 }
 
-SPDLOG_INLINE registry &registry::instance()
-{
+SPDLOG_INLINE registry &registry::instance() {
     static registry s_instance;
     return s_instance;
 }
 
-SPDLOG_INLINE void registry::throw_if_exists_(const std::string &logger_name)
-{
-    if (loggers_.find(logger_name) != loggers_.end())
-    {
+SPDLOG_INLINE void registry::apply_logger_env_levels(std::shared_ptr<logger> new_logger) {
+    std::lock_guard<std::mutex> lock(logger_map_mutex_);
+    auto it = log_levels_.find(new_logger->name());
+    auto new_level = it != log_levels_.end() ? it->second : global_log_level_;
+    new_logger->set_level(new_level);
+}
+
+SPDLOG_INLINE void registry::throw_if_exists_(const std::string &logger_name) {
+    if (loggers_.find(logger_name) != loggers_.end()) {
         throw_spdlog_ex("logger with name '" + logger_name + "' already exists");
     }
 }
 
-SPDLOG_INLINE void registry::register_logger_(std::shared_ptr<logger> new_logger)
-{
-    auto logger_name = new_logger->name();
+SPDLOG_INLINE void registry::register_logger_(std::shared_ptr<logger> new_logger) {
+    auto &logger_name = new_logger->name();
     throw_if_exists_(logger_name);
     loggers_[logger_name] = std::move(new_logger);
 }
 
-} // namespace details
-} // namespace spdlog
+SPDLOG_INLINE void registry::register_or_replace_(std::shared_ptr<logger> new_logger) {
+    loggers_[new_logger->name()] = std::move(new_logger);
+}
+
+}  // namespace details
+}  // namespace spdlog

include/spdlog/details/registry.h

@@ -9,29 +9,29 @@
 // This class is thread safe
 
 #include <spdlog/common.h>
-#include <spdlog/cfg/log_levels.h>
+#include <spdlog/details/periodic_worker.h>
 
 #include <chrono>
 #include <functional>
 #include <memory>
+#include <mutex>
 #include <string>
 #include <unordered_map>
-#include <mutex>
 
 namespace spdlog {
 class logger;
 
 namespace details {
 class thread_pool;
-class periodic_worker;
 
-class SPDLOG_API registry
-{
+class SPDLOG_API registry {
 public:
+    using log_levels = std::unordered_map<std::string, level::level_enum>;
     registry(const registry &) = delete;
     registry &operator=(const registry &) = delete;
 
     void register_logger(std::shared_ptr<logger> new_logger);
+    void register_or_replace(std::shared_ptr<logger> new_logger);
     void initialize_logger(std::shared_ptr<logger> new_logger);
     std::shared_ptr<logger> get(const std::string &logger_name);
     std::shared_ptr<logger> default_logger();
@@ -39,11 +39,14 @@ public:
     // Return raw ptr to the default logger.
     // To be used directly by the spdlog default api (e.g. spdlog::info)
     // This make the default API faster, but cannot be used concurrently with set_default_logger().
-    // e.g do not call set_default_logger() from one thread while calling spdlog::info() from another.
+    // e.g do not call set_default_logger() from one thread while calling spdlog::info() from
+    // another.
     logger *get_default_raw();
 
-    // set default logger.
+    // set default logger and add it to the registry if not registered already.
     // default logger is stored in default_logger_ (for faster retrieval) and in the loggers_ map.
+    // Note: Make sure to unregister it when no longer needed or before calling again with a new
+    // logger.
     void set_default_logger(std::shared_ptr<logger> new_default_logger);
 
     void set_tp(std::shared_ptr<thread_pool> tp);
@@ -61,9 +64,19 @@ public:
 
     void flush_on(level::level_enum log_level);
 
-    void flush_every(std::chrono::seconds interval);
+    template <typename Rep, typename Period>
+    void flush_every(std::chrono::duration<Rep, Period> interval) {
+        std::lock_guard<std::mutex> lock(flusher_mutex_);
+        auto clbk = [this]() { this->flush_all(); };
+        periodic_flusher_ = details::make_unique<periodic_worker>(clbk, interval);
+    }
 
-    void set_error_handler(void (*handler)(const std::string &msg));
+    std::unique_ptr<periodic_worker> &get_flusher() {
+        std::lock_guard<std::mutex> lock(flusher_mutex_);
+        return periodic_flusher_;
+    }
+
+    void set_error_handler(err_handler handler);
 
     void apply_all(const std::function<void(const std::shared_ptr<logger>)> &fun);
 
@@ -80,23 +93,29 @@ public:
 
     void set_automatic_registration(bool automatic_registration);
 
-    void update_levels(cfg::log_levels levels);
+    // set levels for all existing/future loggers. global_level can be null if should not set.
+    void set_levels(log_levels levels, level::level_enum *global_level);
 
     static registry &instance();
 
+    void apply_logger_env_levels(std::shared_ptr<logger> new_logger);
+
 private:
     registry();
     ~registry();
 
     void throw_if_exists_(const std::string &logger_name);
     void register_logger_(std::shared_ptr<logger> new_logger);
+    void register_or_replace_(std::shared_ptr<logger> new_logger);
+    bool set_level_from_cfg_(logger *logger);
     std::mutex logger_map_mutex_, flusher_mutex_;
     std::recursive_mutex tp_mutex_;
     std::unordered_map<std::string, std::shared_ptr<logger>> loggers_;
-    cfg::log_levels levels_;
+    log_levels log_levels_;
     std::unique_ptr<formatter> formatter_;
+    spdlog::level::level_enum global_log_level_ = level::info;
     level::level_enum flush_level_ = level::off;
-    void (*err_handler_)(const std::string &msg);
+    err_handler err_handler_;
     std::shared_ptr<thread_pool> tp_;
     std::unique_ptr<periodic_worker> periodic_flusher_;
     std::shared_ptr<logger> default_logger_;
@@ -104,9 +123,9 @@ private:
     size_t backtrace_n_messages_ = 0;
 };
 
-} // namespace details
-} // namespace spdlog
+}  // namespace details
+}  // namespace spdlog
 
 #ifdef SPDLOG_HEADER_ONLY
-#include "registry-inl.h"
+    #include "registry-inl.h"
 #endif

include/spdlog/details/synchronous_factory.h

@@ -10,15 +10,13 @@ namespace spdlog {
 // Default logger factory-  creates synchronous loggers
 class logger;
 
-struct synchronous_factory
-{
-    template<typename Sink, typename... SinkArgs>
-    static std::shared_ptr<spdlog::logger> create(std::string logger_name, SinkArgs &&... args)
-    {
+struct synchronous_factory {
+    template <typename Sink, typename... SinkArgs>
+    static std::shared_ptr<spdlog::logger> create(std::string logger_name, SinkArgs &&...args) {
         auto sink = std::make_shared<Sink>(std::forward<SinkArgs>(args)...);
         auto new_logger = std::make_shared<spdlog::logger>(std::move(logger_name), std::move(sink));
         details::registry::instance().initialize_logger(new_logger);
         return new_logger;
     }
 };
-} // namespace spdlog
+}  // namespace spdlog

include/spdlog/details/tcp_client-windows.h

@@ -8,12 +8,12 @@
 #include <spdlog/common.h>
 #include <spdlog/details/os.h>
 
+#include <stdio.h>
+#include <stdlib.h>
+#include <string>
 #include <windows.h>
 #include <winsock2.h>
 #include <ws2tcpip.h>
-#include <stdlib.h>
-#include <stdio.h>
-#include <string>
 
 #pragma comment(lib, "Ws2_32.lib")
 #pragma comment(lib, "Mswsock.lib")
@@ -21,94 +21,61 @@
 
 namespace spdlog {
 namespace details {
-class tcp_client
-{
+class tcp_client {
     SOCKET socket_ = INVALID_SOCKET;
 
-    static bool winsock_initialized_()
-    {
-        SOCKET s = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
-        if (s == INVALID_SOCKET)
-        {
-            return false;
-        }
-        else
-        {
-            closesocket(s);
-            return true;
-        }
-    }
-
-    static void init_winsock_()
-    {
+    static void init_winsock_() {
         WSADATA wsaData;
         auto rv = WSAStartup(MAKEWORD(2, 2), &wsaData);
-        if (rv != 0)
-        {
+        if (rv != 0) {
             throw_winsock_error_("WSAStartup failed", ::WSAGetLastError());
         }
     }
 
-    static void throw_winsock_error_(const std::string &msg, int last_error)
-    {
+    static void throw_winsock_error_(const std::string &msg, int last_error) {
         char buf[512];
-        ::FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS, NULL, last_error,
-            MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), buf, (sizeof(buf) / sizeof(char)), NULL);
+        ::FormatMessageA(FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS, NULL,
+                         last_error, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), buf,
+                         (sizeof(buf) / sizeof(char)), NULL);
 
-        throw_spdlog_ex(fmt::format("tcp_sink - {}: {}", msg, buf));
+        throw_spdlog_ex(fmt_lib::format("tcp_sink - {}: {}", msg, buf));
     }
 
 public:
-    bool is_connected() const
-    {
-        return socket_ != INVALID_SOCKET;
+    tcp_client() { init_winsock_(); }
+
+    ~tcp_client() {
+        close();
+        ::WSACleanup();
     }
 
-    void close()
-    {
+    bool is_connected() const { return socket_ != INVALID_SOCKET; }
+
+    void close() {
         ::closesocket(socket_);
         socket_ = INVALID_SOCKET;
-        WSACleanup();
     }
 
-    SOCKET fd() const
-    {
-        return socket_;
-    }
-
-    ~tcp_client()
-    {
-        close();
-    }
+    SOCKET fd() const { return socket_; }
 
     // try to connect or throw on failure
-    void connect(const std::string &host, int port)
-    {
-        // initialize winsock if needed
-        if (!winsock_initialized_())
-        {
-            init_winsock_();
-        }
-
-        if (is_connected())
-        {
+    void connect(const std::string &host, int port) {
+        if (is_connected()) {
             close();
         }
-        struct addrinfo hints
-        {};
+        struct addrinfo hints {};
         ZeroMemory(&hints, sizeof(hints));
 
-        hints.ai_family = AF_INET;       // IPv4
-        hints.ai_socktype = SOCK_STREAM; // TCP
-        hints.ai_flags = AI_NUMERICSERV; // port passed as as numeric value
+        hints.ai_family = AF_UNSPEC;      // To work with IPv4, IPv6, and so on
+        hints.ai_socktype = SOCK_STREAM;  // TCP
+        hints.ai_flags = AI_NUMERICSERV;  // port passed as as numeric value
         hints.ai_protocol = 0;
 
         auto port_str = std::to_string(port);
         struct addrinfo *addrinfo_result;
         auto rv = ::getaddrinfo(host.c_str(), port_str.c_str(), &hints, &addrinfo_result);
         int last_error = 0;
-        if (rv != 0)
-        {
+        if (rv != 0) {
             last_error = ::WSAGetLastError();
             WSACleanup();
             throw_winsock_error_("getaddrinfo failed", last_error);
@@ -116,54 +83,47 @@ public:
 
         // Try each address until we successfully connect(2).
 
-        for (auto *rp = addrinfo_result; rp != nullptr; rp = rp->ai_next)
-        {
+        for (auto *rp = addrinfo_result; rp != nullptr; rp = rp->ai_next) {
             socket_ = socket(rp->ai_family, rp->ai_socktype, rp->ai_protocol);
-            if (socket_ == INVALID_SOCKET)
-            {
+            if (socket_ == INVALID_SOCKET) {
                 last_error = ::WSAGetLastError();
                 WSACleanup();
                 continue;
             }
-            if (::connect(socket_, rp->ai_addr, (int)rp->ai_addrlen) == 0)
-            {
+            if (::connect(socket_, rp->ai_addr, (int)rp->ai_addrlen) == 0) {
                 break;
-            }
-            else
-            {
+            } else {
                 last_error = ::WSAGetLastError();
                 close();
             }
         }
         ::freeaddrinfo(addrinfo_result);
-        if (socket_ == INVALID_SOCKET)
-        {
+        if (socket_ == INVALID_SOCKET) {
             WSACleanup();
             throw_winsock_error_("connect failed", last_error);
         }
 
         // set TCP_NODELAY
         int enable_flag = 1;
-        ::setsockopt(socket_, IPPROTO_TCP, TCP_NODELAY, (char *)&enable_flag, sizeof(enable_flag));
+        ::setsockopt(socket_, IPPROTO_TCP, TCP_NODELAY, reinterpret_cast<char *>(&enable_flag),
+                     sizeof(enable_flag));
     }
 
     // Send exactly n_bytes of the given data.
     // On error close the connection and throw.
-    void send(const char *data, size_t n_bytes)
-    {
+    void send(const char *data, size_t n_bytes) {
         size_t bytes_sent = 0;
-        while (bytes_sent < n_bytes)
-        {
+        while (bytes_sent < n_bytes) {
             const int send_flags = 0;
-            auto write_result = ::send(socket_, data + bytes_sent, (int)(n_bytes - bytes_sent), send_flags);
-            if (write_result == SOCKET_ERROR)
-            {
+            auto write_result =
+                ::send(socket_, data + bytes_sent, (int)(n_bytes - bytes_sent), send_flags);
+            if (write_result == SOCKET_ERROR) {
                 int last_error = ::WSAGetLastError();
                 close();
                 throw_winsock_error_("send failed", last_error);
             }
 
-            if (write_result == 0) // (probably should not happen but in any case..)
+            if (write_result == 0)  // (probably should not happen but in any case..)
             {
                 break;
             }
@@ -171,5 +131,5 @@ public:
         }
     }
 };
-} // namespace details
-} // namespace spdlog
+}  // namespace details
+}  // namespace spdlog

include/spdlog/details/tcp_client.h

@@ -4,136 +4,118 @@
 #pragma once
 
 #ifdef _WIN32
-#error include tcp_client-windows.h instead
+    #error include tcp_client-windows.h instead
 #endif
 
 // tcp client helper
 #include <spdlog/common.h>
 #include <spdlog/details/os.h>
 
-#include <sys/socket.h>
 #include <arpa/inet.h>
-#include <unistd.h>
 #include <netdb.h>
+#include <netinet/in.h>
 #include <netinet/tcp.h>
+#include <sys/socket.h>
+#include <unistd.h>
 
 #include <string>
 
 namespace spdlog {
 namespace details {
-class tcp_client
-{
+class tcp_client {
     int socket_ = -1;
 
 public:
-    bool is_connected() const
-    {
-        return socket_ != -1;
-    }
+    bool is_connected() const { return socket_ != -1; }
 
-    void close()
-    {
-        if (is_connected())
-        {
+    void close() {
+        if (is_connected()) {
             ::close(socket_);
             socket_ = -1;
         }
     }
 
-    int fd() const
-    {
-        return socket_;
-    }
+    int fd() const { return socket_; }
 
-    ~tcp_client()
-    {
-        close();
-    }
+    ~tcp_client() { close(); }
 
     // try to connect or throw on failure
-    void connect(const std::string &host, int port)
-    {
+    void connect(const std::string &host, int port) {
         close();
-        struct addrinfo hints
-        {};
+        struct addrinfo hints {};
         memset(&hints, 0, sizeof(struct addrinfo));
-        hints.ai_family = AF_INET;       // IPv4
-        hints.ai_socktype = SOCK_STREAM; // TCP
-        hints.ai_flags = AI_NUMERICSERV; // port passed as as numeric value
+        hints.ai_family = AF_UNSPEC;      // To work with IPv4, IPv6, and so on
+        hints.ai_socktype = SOCK_STREAM;  // TCP
+        hints.ai_flags = AI_NUMERICSERV;  // port passed as as numeric value
         hints.ai_protocol = 0;
 
         auto port_str = std::to_string(port);
         struct addrinfo *addrinfo_result;
         auto rv = ::getaddrinfo(host.c_str(), port_str.c_str(), &hints, &addrinfo_result);
-        if (rv != 0)
-        {
-            auto msg = fmt::format("::getaddrinfo failed: {}", gai_strerror(rv));
-            throw_spdlog_ex(msg);
+        if (rv != 0) {
+            throw_spdlog_ex(fmt_lib::format("::getaddrinfo failed: {}", gai_strerror(rv)));
         }
 
         // Try each address until we successfully connect(2).
         int last_errno = 0;
-        for (auto *rp = addrinfo_result; rp != nullptr; rp = rp->ai_next)
-        {
-            int const flags = SOCK_CLOEXEC;
+        for (auto *rp = addrinfo_result; rp != nullptr; rp = rp->ai_next) {
+#if defined(SOCK_CLOEXEC)
+            const int flags = SOCK_CLOEXEC;
+#else
+            const int flags = 0;
+#endif
             socket_ = ::socket(rp->ai_family, rp->ai_socktype | flags, rp->ai_protocol);
-            if (socket_ == -1)
-            {
+            if (socket_ == -1) {
                 last_errno = errno;
                 continue;
             }
             rv = ::connect(socket_, rp->ai_addr, rp->ai_addrlen);
-            if (rv == 0)
-            {
+            if (rv == 0) {
                 break;
             }
-            else
-            {
-                last_errno = errno;
-                ::close(socket_);
-                socket_ = -1;
-            }
+            last_errno = errno;
+            ::close(socket_);
+            socket_ = -1;
         }
         ::freeaddrinfo(addrinfo_result);
-        if (socket_ == -1)
-        {
+        if (socket_ == -1) {
             throw_spdlog_ex("::connect failed", last_errno);
         }
 
         // set TCP_NODELAY
         int enable_flag = 1;
-        ::setsockopt(socket_, IPPROTO_TCP, TCP_NODELAY, (char *)&enable_flag, sizeof(enable_flag));
+        ::setsockopt(socket_, IPPROTO_TCP, TCP_NODELAY, reinterpret_cast<char *>(&enable_flag),
+                     sizeof(enable_flag));
 
         // prevent sigpipe on systems where MSG_NOSIGNAL is not available
 #if defined(SO_NOSIGPIPE) && !defined(MSG_NOSIGNAL)
-        ::setsockopt(socket_, SOL_SOCKET, SO_NOSIGPIPE, (char *)&enable_flag, sizeof(enable_flag));
+        ::setsockopt(socket_, SOL_SOCKET, SO_NOSIGPIPE, reinterpret_cast<char *>(&enable_flag),
+                     sizeof(enable_flag));
 #endif
 
 #if !defined(SO_NOSIGPIPE) && !defined(MSG_NOSIGNAL)
-#error "tcp_sink would raise SIGPIPE since niether SO_NOSIGPIPE nor MSG_NOSIGNAL are available"
+    #error "tcp_sink would raise SIGPIPE since neither SO_NOSIGPIPE nor MSG_NOSIGNAL are available"
 #endif
     }
 
     // Send exactly n_bytes of the given data.
     // On error close the connection and throw.
-    void send(const char *data, size_t n_bytes)
-    {
+    void send(const char *data, size_t n_bytes) {
         size_t bytes_sent = 0;
-        while (bytes_sent < n_bytes)
-        {
+        while (bytes_sent < n_bytes) {
 #if defined(MSG_NOSIGNAL)
             const int send_flags = MSG_NOSIGNAL;
 #else
             const int send_flags = 0;
 #endif
-            auto write_result = ::send(socket_, data + bytes_sent, n_bytes - bytes_sent, send_flags);
-            if (write_result < 0)
-            {
+            auto write_result =
+                ::send(socket_, data + bytes_sent, n_bytes - bytes_sent, send_flags);
+            if (write_result < 0) {
                 close();
                 throw_spdlog_ex("write(2) failed", errno);
             }
 
-            if (write_result == 0) // (probably should not happen but in any case..)
+            if (write_result == 0)  // (probably should not happen but in any case..)
             {
                 break;
             }
@@ -141,5 +123,5 @@ public:
         }
     }
 };
-} // namespace details
-} // namespace spdlog
+}  // namespace details
+}  // namespace spdlog

include/spdlog/details/thread_pool-inl.h

@@ -4,121 +4,122 @@
 #pragma once
 
 #ifndef SPDLOG_HEADER_ONLY
-#include <spdlog/details/thread_pool.h>
+    #include <spdlog/details/thread_pool.h>
 #endif
 
-#include <spdlog/common.h>
 #include <cassert>
+#include <spdlog/common.h>
 
 namespace spdlog {
 namespace details {
 
-SPDLOG_INLINE thread_pool::thread_pool(size_t q_max_items, size_t threads_n, std::function<void()> on_thread_start)
-    : q_(q_max_items)
-{
-    if (threads_n == 0 || threads_n > 1000)
-    {
-        throw_spdlog_ex("spdlog::thread_pool(): invalid threads_n param (valid "
-                        "range is 1-1000)");
+SPDLOG_INLINE thread_pool::thread_pool(size_t q_max_items,
+                                       size_t threads_n,
+                                       std::function<void()> on_thread_start,
+                                       std::function<void()> on_thread_stop)
+    : q_(q_max_items) {
+    if (threads_n == 0 || threads_n > 1000) {
+        throw_spdlog_ex(
+            "spdlog::thread_pool(): invalid threads_n param (valid "
+            "range is 1-1000)");
     }
-    for (size_t i = 0; i < threads_n; i++)
-    {
-        threads_.emplace_back([this, on_thread_start] {
+    for (size_t i = 0; i < threads_n; i++) {
+        threads_.emplace_back([this, on_thread_start, on_thread_stop] {
             on_thread_start();
             this->thread_pool::worker_loop_();
+            on_thread_stop();
         });
     }
 }
 
+SPDLOG_INLINE thread_pool::thread_pool(size_t q_max_items,
+                                       size_t threads_n,
+                                       std::function<void()> on_thread_start)
+    : thread_pool(q_max_items, threads_n, std::move(on_thread_start), [] {}) {}
+
 SPDLOG_INLINE thread_pool::thread_pool(size_t q_max_items, size_t threads_n)
-    : thread_pool(q_max_items, threads_n, [] {})
-{}
+    : thread_pool(q_max_items, threads_n, [] {}, [] {}) {}
 
 // message all threads to terminate gracefully join them
-SPDLOG_INLINE thread_pool::~thread_pool()
-{
-    SPDLOG_TRY
-    {
-        for (size_t i = 0; i < threads_.size(); i++)
-        {
+SPDLOG_INLINE thread_pool::~thread_pool() {
+    SPDLOG_TRY {
+        for (size_t i = 0; i < threads_.size(); i++) {
             post_async_msg_(async_msg(async_msg_type::terminate), async_overflow_policy::block);
         }
 
-        for (auto &t : threads_)
-        {
+        for (auto &t : threads_) {
             t.join();
         }
     }
-    SPDLOG_CATCH_ALL() {}
+    SPDLOG_CATCH_STD
 }
 
-void SPDLOG_INLINE thread_pool::post_log(async_logger_ptr &&worker_ptr, const details::log_msg &msg, async_overflow_policy overflow_policy)
-{
+void SPDLOG_INLINE thread_pool::post_log(async_logger_ptr &&worker_ptr,
+                                         const details::log_msg &msg,
+                                         async_overflow_policy overflow_policy) {
     async_msg async_m(std::move(worker_ptr), async_msg_type::log, msg);
     post_async_msg_(std::move(async_m), overflow_policy);
 }
 
-void SPDLOG_INLINE thread_pool::post_flush(async_logger_ptr &&worker_ptr, async_overflow_policy overflow_policy)
-{
+void SPDLOG_INLINE thread_pool::post_flush(async_logger_ptr &&worker_ptr,
+                                           async_overflow_policy overflow_policy) {
     post_async_msg_(async_msg(std::move(worker_ptr), async_msg_type::flush), overflow_policy);
 }
 
-size_t SPDLOG_INLINE thread_pool::overrun_counter()
-{
-    return q_.overrun_counter();
-}
+size_t SPDLOG_INLINE thread_pool::overrun_counter() { return q_.overrun_counter(); }
 
-void SPDLOG_INLINE thread_pool::post_async_msg_(async_msg &&new_msg, async_overflow_policy overflow_policy)
-{
-    if (overflow_policy == async_overflow_policy::block)
-    {
+void SPDLOG_INLINE thread_pool::reset_overrun_counter() { q_.reset_overrun_counter(); }
+
+size_t SPDLOG_INLINE thread_pool::discard_counter() { return q_.discard_counter(); }
+
+void SPDLOG_INLINE thread_pool::reset_discard_counter() { q_.reset_discard_counter(); }
+
+size_t SPDLOG_INLINE thread_pool::queue_size() { return q_.size(); }
+
+void SPDLOG_INLINE thread_pool::post_async_msg_(async_msg &&new_msg,
+                                                async_overflow_policy overflow_policy) {
+    if (overflow_policy == async_overflow_policy::block) {
         q_.enqueue(std::move(new_msg));
-    }
-    else
-    {
+    } else if (overflow_policy == async_overflow_policy::overrun_oldest) {
         q_.enqueue_nowait(std::move(new_msg));
+    } else {
+        assert(overflow_policy == async_overflow_policy::discard_new);
+        q_.enqueue_if_have_room(std::move(new_msg));
     }
 }
 
-void SPDLOG_INLINE thread_pool::worker_loop_()
-{
-    while (process_next_msg_()) {}
+void SPDLOG_INLINE thread_pool::worker_loop_() {
+    while (process_next_msg_()) {
+    }
 }
 
 // process next message in the queue
-// return true if this thread should still be active (while no terminate msg
-// was received)
-bool SPDLOG_INLINE thread_pool::process_next_msg_()
-{
+// returns true if this thread should still be active (while no terminated msg was received)
+bool SPDLOG_INLINE thread_pool::process_next_msg_() {
     async_msg incoming_async_msg;
-    bool dequeued = q_.dequeue_for(incoming_async_msg, std::chrono::seconds(10));
-    if (!dequeued)
-    {
-        return true;
-    }
+    q_.dequeue(incoming_async_msg);
 
-    switch (incoming_async_msg.msg_type)
-    {
-    case async_msg_type::log: {
-        incoming_async_msg.worker_ptr->backend_sink_it_(incoming_async_msg);
-        return true;
-    }
-    case async_msg_type::flush: {
-        incoming_async_msg.worker_ptr->backend_flush_();
-        return true;
-    }
+    switch (incoming_async_msg.msg_type) {
+        case async_msg_type::log: {
+            incoming_async_msg.worker_ptr->backend_sink_it_(incoming_async_msg);
+            return true;
+        }
+        case async_msg_type::flush: {
+            incoming_async_msg.worker_ptr->backend_flush_();
+            return true;
+        }
 
-    case async_msg_type::terminate: {
-        return false;
-    }
+        case async_msg_type::terminate: {
+            return false;
+        }
 
-    default: {
-        assert(false);
-    }
+        default: {
+            assert(false);
+        }
     }
 
     return true;
 }
 
-} // namespace details
-} // namespace spdlog
+}  // namespace details
+}  // namespace spdlog

include/spdlog/details/thread_pool.h

@@ -8,10 +8,10 @@
 #include <spdlog/details/os.h>
 
 #include <chrono>
+#include <functional>
 #include <memory>
 #include <thread>
 #include <vector>
-#include <functional>
 
 namespace spdlog {
 class async_logger;
@@ -20,18 +20,11 @@ namespace details {
 
 using async_logger_ptr = std::shared_ptr<spdlog::async_logger>;
 
-enum class async_msg_type
-{
-    log,
-    flush,
-    terminate
-};
+enum class async_msg_type { log, flush, terminate };
 
-#include <spdlog/details/log_msg_buffer.h>
 // Async msg to move to/from the queue
 // Movable only. should never be copied
-struct async_msg : log_msg_buffer
-{
+struct async_msg : log_msg_buffer {
     async_msg_type msg_type{async_msg_type::log};
     async_logger_ptr worker_ptr;
 
@@ -44,59 +37,63 @@ struct async_msg : log_msg_buffer
 // support for vs2013 move
 #if defined(_MSC_VER) && _MSC_VER <= 1800
     async_msg(async_msg &&other)
-        : log_msg_buffer(std::move(other))
-        , msg_type(other.msg_type)
-        , worker_ptr(std::move(other.worker_ptr))
-    {}
+        : log_msg_buffer(std::move(other)),
+          msg_type(other.msg_type),
+          worker_ptr(std::move(other.worker_ptr)) {}
 
-    async_msg &operator=(async_msg &&other)
-    {
+    async_msg &operator=(async_msg &&other) {
         *static_cast<log_msg_buffer *>(this) = std::move(other);
         msg_type = other.msg_type;
         worker_ptr = std::move(other.worker_ptr);
         return *this;
     }
-#else // (_MSC_VER) && _MSC_VER <= 1800
+#else  // (_MSC_VER) && _MSC_VER <= 1800
     async_msg(async_msg &&) = default;
     async_msg &operator=(async_msg &&) = default;
 #endif
 
     // construct from log_msg with given type
     async_msg(async_logger_ptr &&worker, async_msg_type the_type, const details::log_msg &m)
-        : log_msg_buffer{m}
-        , msg_type{the_type}
-        , worker_ptr{std::move(worker)}
-    {}
+        : log_msg_buffer{m},
+          msg_type{the_type},
+          worker_ptr{std::move(worker)} {}
 
     async_msg(async_logger_ptr &&worker, async_msg_type the_type)
-        : log_msg_buffer{}
-        , msg_type{the_type}
-        , worker_ptr{std::move(worker)}
-    {}
+        : log_msg_buffer{},
+          msg_type{the_type},
+          worker_ptr{std::move(worker)} {}
 
     explicit async_msg(async_msg_type the_type)
-        : async_msg{nullptr, the_type}
-    {}
+        : async_msg{nullptr, the_type} {}
 };
 
-class SPDLOG_API thread_pool
-{
+class SPDLOG_API thread_pool {
 public:
     using item_type = async_msg;
     using q_type = details::mpmc_blocking_queue<item_type>;
 
+    thread_pool(size_t q_max_items,
+                size_t threads_n,
+                std::function<void()> on_thread_start,
+                std::function<void()> on_thread_stop);
     thread_pool(size_t q_max_items, size_t threads_n, std::function<void()> on_thread_start);
     thread_pool(size_t q_max_items, size_t threads_n);
 
-    // message all threads to terminate gracefully join them
+    // message all threads to terminate gracefully and join them
     ~thread_pool();
 
     thread_pool(const thread_pool &) = delete;
     thread_pool &operator=(thread_pool &&) = delete;
 
-    void post_log(async_logger_ptr &&worker_ptr, const details::log_msg &msg, async_overflow_policy overflow_policy);
+    void post_log(async_logger_ptr &&worker_ptr,
+                  const details::log_msg &msg,
+                  async_overflow_policy overflow_policy);
     void post_flush(async_logger_ptr &&worker_ptr, async_overflow_policy overflow_policy);
     size_t overrun_counter();
+    void reset_overrun_counter();
+    size_t discard_counter();
+    void reset_discard_counter();
+    size_t queue_size();
 
 private:
     q_type q_;
@@ -112,9 +109,9 @@ private:
     bool process_next_msg_();
 };
 
-} // namespace details
-} // namespace spdlog
+}  // namespace details
+}  // namespace spdlog
 
 #ifdef SPDLOG_HEADER_ONLY
-#include "thread_pool-inl.h"
+    #include "thread_pool-inl.h"
 #endif

include/spdlog/details/udp_client-windows.h

@@ -0,0 +1,98 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+// Helper RAII over winsock udp client socket.
+// Will throw on construction if socket creation failed.
+
+#include <spdlog/common.h>
+#include <spdlog/details/os.h>
+#include <spdlog/details/windows_include.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string>
+#include <winsock2.h>
+#include <ws2tcpip.h>
+
+#if defined(_MSC_VER)
+    #pragma comment(lib, "Ws2_32.lib")
+    #pragma comment(lib, "Mswsock.lib")
+    #pragma comment(lib, "AdvApi32.lib")
+#endif
+
+namespace spdlog {
+namespace details {
+class udp_client {
+    static constexpr int TX_BUFFER_SIZE = 1024 * 10;
+    SOCKET socket_ = INVALID_SOCKET;
+    sockaddr_in addr_ = {};
+
+    static void init_winsock_() {
+        WSADATA wsaData;
+        auto rv = ::WSAStartup(MAKEWORD(2, 2), &wsaData);
+        if (rv != 0) {
+            throw_winsock_error_("WSAStartup failed", ::WSAGetLastError());
+        }
+    }
+
+    static void throw_winsock_error_(const std::string &msg, int last_error) {
+        char buf[512];
+        ::FormatMessageA(FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS, NULL,
+                         last_error, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), buf,
+                         (sizeof(buf) / sizeof(char)), NULL);
+
+        throw_spdlog_ex(fmt_lib::format("udp_sink - {}: {}", msg, buf));
+    }
+
+    void cleanup_() {
+        if (socket_ != INVALID_SOCKET) {
+            ::closesocket(socket_);
+        }
+        socket_ = INVALID_SOCKET;
+        ::WSACleanup();
+    }
+
+public:
+    udp_client(const std::string &host, uint16_t port) {
+        init_winsock_();
+
+        addr_.sin_family = PF_INET;
+        addr_.sin_port = htons(port);
+        addr_.sin_addr.s_addr = INADDR_ANY;
+        if (InetPtonA(PF_INET, host.c_str(), &addr_.sin_addr.s_addr) != 1) {
+            int last_error = ::WSAGetLastError();
+            ::WSACleanup();
+            throw_winsock_error_("error: Invalid address!", last_error);
+        }
+
+        socket_ = ::socket(PF_INET, SOCK_DGRAM, 0);
+        if (socket_ == INVALID_SOCKET) {
+            int last_error = ::WSAGetLastError();
+            ::WSACleanup();
+            throw_winsock_error_("error: Create Socket failed", last_error);
+        }
+
+        int option_value = TX_BUFFER_SIZE;
+        if (::setsockopt(socket_, SOL_SOCKET, SO_SNDBUF,
+                         reinterpret_cast<const char *>(&option_value), sizeof(option_value)) < 0) {
+            int last_error = ::WSAGetLastError();
+            cleanup_();
+            throw_winsock_error_("error: setsockopt(SO_SNDBUF) Failed!", last_error);
+        }
+    }
+
+    ~udp_client() { cleanup_(); }
+
+    SOCKET fd() const { return socket_; }
+
+    void send(const char *data, size_t n_bytes) {
+        socklen_t tolen = sizeof(struct sockaddr);
+        if (::sendto(socket_, data, static_cast<int>(n_bytes), 0, (struct sockaddr *)&addr_,
+                     tolen) == -1) {
+            throw_spdlog_ex("sendto(2) failed", errno);
+        }
+    }
+};
+}  // namespace details
+}  // namespace spdlog

include/spdlog/details/udp_client.h

@@ -0,0 +1,81 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+// Helper RAII over unix udp client socket.
+// Will throw on construction if the socket creation failed.
+
+#ifdef _WIN32
+    #error "include udp_client-windows.h instead"
+#endif
+
+#include <arpa/inet.h>
+#include <cstring>
+#include <netdb.h>
+#include <netinet/in.h>
+#include <netinet/udp.h>
+#include <spdlog/common.h>
+#include <spdlog/details/os.h>
+#include <sys/socket.h>
+#include <unistd.h>
+
+#include <string>
+
+namespace spdlog {
+namespace details {
+
+class udp_client {
+    static constexpr int TX_BUFFER_SIZE = 1024 * 10;
+    int socket_ = -1;
+    struct sockaddr_in sockAddr_;
+
+    void cleanup_() {
+        if (socket_ != -1) {
+            ::close(socket_);
+            socket_ = -1;
+        }
+    }
+
+public:
+    udp_client(const std::string &host, uint16_t port) {
+        socket_ = ::socket(PF_INET, SOCK_DGRAM, 0);
+        if (socket_ < 0) {
+            throw_spdlog_ex("error: Create Socket Failed!");
+        }
+
+        int option_value = TX_BUFFER_SIZE;
+        if (::setsockopt(socket_, SOL_SOCKET, SO_SNDBUF,
+                         reinterpret_cast<const char *>(&option_value), sizeof(option_value)) < 0) {
+            cleanup_();
+            throw_spdlog_ex("error: setsockopt(SO_SNDBUF) Failed!");
+        }
+
+        sockAddr_.sin_family = AF_INET;
+        sockAddr_.sin_port = htons(port);
+
+        if (::inet_aton(host.c_str(), &sockAddr_.sin_addr) == 0) {
+            cleanup_();
+            throw_spdlog_ex("error: Invalid address!");
+        }
+
+        ::memset(sockAddr_.sin_zero, 0x00, sizeof(sockAddr_.sin_zero));
+    }
+
+    ~udp_client() { cleanup_(); }
+
+    int fd() const { return socket_; }
+
+    // Send exactly n_bytes of the given data.
+    // On error close the connection and throw.
+    void send(const char *data, size_t n_bytes) {
+        ssize_t toslen = 0;
+        socklen_t tolen = sizeof(struct sockaddr);
+        if ((toslen = ::sendto(socket_, data, n_bytes, 0, (struct sockaddr *)&sockAddr_, tolen)) ==
+            -1) {
+            throw_spdlog_ex("sendto(2) failed", errno);
+        }
+    }
+};
+}  // namespace details
+}  // namespace spdlog

include/spdlog/details/windows_include.h

@@ -1,11 +1,11 @@
 #pragma once
 
 #ifndef NOMINMAX
-#define NOMINMAX // prevent windows redefining min/max
+    #define NOMINMAX  // prevent windows redefining min/max
 #endif
 
 #ifndef WIN32_LEAN_AND_MEAN
-#define WIN32_LEAN_AND_MEAN
+    #define WIN32_LEAN_AND_MEAN
 #endif
 
 #include <windows.h>

include/spdlog/fmt/bin_to_hex.h

@@ -6,10 +6,21 @@
 #pragma once
 
 #include <cctype>
+#include <spdlog/common.h>
+
+#if defined(__has_include)
+    #if __has_include(<version>)
+        #include <version>
+    #endif
+#endif
+
+#if __cpp_lib_span >= 202002L
+    #include <span>
+#endif
 
 //
 // Support for logging binary data as hex
-// format flags:
+// format flags, any combination of the following:
 // {:X} - print in uppercase.
 // {:s} - don't separate each byte with space.
 // {:p} - don't print the position on each line start.
@@ -28,93 +39,100 @@
 namespace spdlog {
 namespace details {
 
-template<typename It>
-class dump_info
-{
+template <typename It>
+class dump_info {
 public:
     dump_info(It range_begin, It range_end, size_t size_per_line)
-        : begin_(range_begin)
-        , end_(range_end)
-        , size_per_line_(size_per_line)
-    {}
+        : begin_(range_begin),
+          end_(range_end),
+          size_per_line_(size_per_line) {}
 
-    It begin() const
-    {
-        return begin_;
-    }
-    It end() const
-    {
-        return end_;
-    }
-    size_t size_per_line() const
-    {
-        return size_per_line_;
-    }
+    // do not use begin() and end() to avoid collision with fmt/ranges
+    It get_begin() const { return begin_; }
+    It get_end() const { return end_; }
+    size_t size_per_line() const { return size_per_line_; }
 
 private:
     It begin_, end_;
     size_t size_per_line_;
 };
-} // namespace details
+}  // namespace details
 
 // create a dump_info that wraps the given container
-template<typename Container>
-inline details::dump_info<typename Container::const_iterator> to_hex(const Container &container, size_t size_per_line = 32)
-{
-    static_assert(sizeof(typename Container::value_type) == 1, "sizeof(Container::value_type) != 1");
+template <typename Container>
+inline details::dump_info<typename Container::const_iterator> to_hex(const Container &container,
+                                                                     size_t size_per_line = 32) {
+    static_assert(sizeof(typename Container::value_type) == 1,
+                  "sizeof(Container::value_type) != 1");
     using Iter = typename Container::const_iterator;
     return details::dump_info<Iter>(std::begin(container), std::end(container), size_per_line);
 }
 
+#if __cpp_lib_span >= 202002L
+
+template <typename Value, size_t Extent>
+inline details::dump_info<typename std::span<Value, Extent>::iterator> to_hex(
+    const std::span<Value, Extent> &container, size_t size_per_line = 32) {
+    using Container = std::span<Value, Extent>;
+    static_assert(sizeof(typename Container::value_type) == 1,
+                  "sizeof(Container::value_type) != 1");
+    using Iter = typename Container::iterator;
+    return details::dump_info<Iter>(std::begin(container), std::end(container), size_per_line);
+}
+
+#endif
+
 // create dump_info from ranges
-template<typename It>
-inline details::dump_info<It> to_hex(const It range_begin, const It range_end, size_t size_per_line = 32)
-{
+template <typename It>
+inline details::dump_info<It> to_hex(const It range_begin,
+                                     const It range_end,
+                                     size_t size_per_line = 32) {
     return details::dump_info<It>(range_begin, range_end, size_per_line);
 }
 
-} // namespace spdlog
+}  // namespace spdlog
 
-namespace fmt {
-
-template<typename T>
-struct formatter<spdlog::details::dump_info<T>>
+namespace
+#ifdef SPDLOG_USE_STD_FORMAT
+    std
+#else
+    fmt
+#endif
 {
-    const char delimiter = ' ';
+
+template <typename T>
+struct formatter<spdlog::details::dump_info<T>, char> {
+    char delimiter = ' ';
     bool put_newlines = true;
     bool put_delimiters = true;
     bool use_uppercase = false;
-    bool put_positions = true; // position on start of each line
+    bool put_positions = true;  // position on start of each line
     bool show_ascii = false;
 
     // parse the format string flags
-    template<typename ParseContext>
-    auto parse(ParseContext &ctx) -> decltype(ctx.begin())
-    {
+    template <typename ParseContext>
+    SPDLOG_CONSTEXPR_FUNC auto parse(ParseContext &ctx) -> decltype(ctx.begin()) {
         auto it = ctx.begin();
-        while (*it && *it != '}')
-        {
-            switch (*it)
-            {
-            case 'X':
-                use_uppercase = true;
-                break;
-            case 's':
-                put_delimiters = false;
-                break;
-            case 'p':
-                put_positions = false;
-                break;
-            case 'n':
-                put_newlines = false;
-                show_ascii = false;
-                break;
-            case 'a':
-                if (put_newlines)
-                {
-                    show_ascii = true;
-                }
-                break;
+        while (it != ctx.end() && *it != '}') {
+            switch (*it) {
+                case 'X':
+                    use_uppercase = true;
+                    break;
+                case 's':
+                    put_delimiters = false;
+                    break;
+                case 'p':
+                    put_positions = false;
+                    break;
+                case 'n':
+                    put_newlines = false;
+                    show_ascii = false;
+                    break;
+                case 'a':
+                    if (put_newlines) {
+                        show_ascii = true;
+                    }
+                    break;
             }
 
             ++it;
@@ -123,39 +141,36 @@ struct formatter<spdlog::details::dump_info<T>>
     }
 
     // format the given bytes range as hex
-    template<typename FormatContext, typename Container>
-    auto format(const spdlog::details::dump_info<Container> &the_range, FormatContext &ctx) -> decltype(ctx.out())
-    {
+    template <typename FormatContext, typename Container>
+    auto format(const spdlog::details::dump_info<Container> &the_range,
+                FormatContext &ctx) const -> decltype(ctx.out()) {
         SPDLOG_CONSTEXPR const char *hex_upper = "0123456789ABCDEF";
         SPDLOG_CONSTEXPR const char *hex_lower = "0123456789abcdef";
         const char *hex_chars = use_uppercase ? hex_upper : hex_lower;
 
-#if FMT_VERSION < 60000
+#if !defined(SPDLOG_USE_STD_FORMAT) && FMT_VERSION < 60000
         auto inserter = ctx.begin();
 #else
         auto inserter = ctx.out();
 #endif
 
         int size_per_line = static_cast<int>(the_range.size_per_line());
-        auto start_of_line = the_range.begin();
-        for (auto i = the_range.begin(); i != the_range.end(); i++)
-        {
+        auto start_of_line = the_range.get_begin();
+        for (auto i = the_range.get_begin(); i != the_range.get_end(); i++) {
             auto ch = static_cast<unsigned char>(*i);
 
-            if (put_newlines && (i == the_range.begin() || i - start_of_line >= size_per_line))
-            {
-                if (show_ascii && i != the_range.begin())
-                {
+            if (put_newlines &&
+                (i == the_range.get_begin() || i - start_of_line >= size_per_line)) {
+                if (show_ascii && i != the_range.get_begin()) {
                     *inserter++ = delimiter;
                     *inserter++ = delimiter;
-                    for (auto j = start_of_line; j < i; j++)
-                    {
+                    for (auto j = start_of_line; j < i; j++) {
                         auto pc = static_cast<unsigned char>(*j);
                         *inserter++ = std::isprint(pc) ? static_cast<char>(*j) : '.';
                     }
                 }
 
-                put_newline(inserter, static_cast<size_t>(i - the_range.begin()));
+                put_newline(inserter, static_cast<size_t>(i - the_range.get_begin()));
 
                 // put first byte without delimiter in front of it
                 *inserter++ = hex_chars[(ch >> 4) & 0x0f];
@@ -164,33 +179,28 @@ struct formatter<spdlog::details::dump_info<T>>
                 continue;
             }
 
-            if (put_delimiters)
-            {
+            if (put_delimiters && i != the_range.get_begin()) {
                 *inserter++ = delimiter;
             }
 
             *inserter++ = hex_chars[(ch >> 4) & 0x0f];
             *inserter++ = hex_chars[ch & 0x0f];
         }
-        if (show_ascii) // add ascii to last line
+        if (show_ascii)  // add ascii to last line
         {
-            if (the_range.end() - the_range.begin() > size_per_line)
-            {
-                auto blank_num = size_per_line - (the_range.end() - start_of_line);
-                while (blank_num-- > 0)
-                {
+            if (the_range.get_end() - the_range.get_begin() > size_per_line) {
+                auto blank_num = size_per_line - (the_range.get_end() - start_of_line);
+                while (blank_num-- > 0) {
                     *inserter++ = delimiter;
                     *inserter++ = delimiter;
-                    if (put_delimiters)
-                    {
+                    if (put_delimiters) {
                         *inserter++ = delimiter;
                     }
                 }
             }
             *inserter++ = delimiter;
             *inserter++ = delimiter;
-            for (auto j = start_of_line; j != the_range.end(); j++)
-            {
+            for (auto j = start_of_line; j != the_range.get_end(); j++) {
                 auto pc = static_cast<unsigned char>(*j);
                 *inserter++ = std::isprint(pc) ? static_cast<char>(*j) : '.';
             }
@@ -199,18 +209,16 @@ struct formatter<spdlog::details::dump_info<T>>
     }
 
     // put newline(and position header)
-    template<typename It>
-    void put_newline(It inserter, std::size_t pos)
-    {
+    template <typename It>
+    void put_newline(It inserter, std::size_t pos) const {
 #ifdef _WIN32
         *inserter++ = '\r';
 #endif
         *inserter++ = '\n';
 
-        if (put_positions)
-        {
-            fmt::format_to(inserter, "{:<04X}: ", pos);
+        if (put_positions) {
+            spdlog::fmt_lib::format_to(inserter, SPDLOG_FMT_STRING("{:04X}: "), pos);
         }
     }
 };
-} // namespace fmt
+}  // namespace std

include/spdlog/fmt/bundled/args.h

@@ -0,0 +1,220 @@
+// Formatting library for C++ - dynamic argument lists
+//
+// Copyright (c) 2012 - present, Victor Zverovich
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+#ifndef FMT_ARGS_H_
+#define FMT_ARGS_H_
+
+#ifndef FMT_MODULE
+#  include <functional>  // std::reference_wrapper
+#  include <memory>      // std::unique_ptr
+#  include <vector>
+#endif
+
+#include "format.h"  // std_string_view
+
+FMT_BEGIN_NAMESPACE
+namespace detail {
+
+template <typename T> struct is_reference_wrapper : std::false_type {};
+template <typename T>
+struct is_reference_wrapper<std::reference_wrapper<T>> : std::true_type {};
+
+template <typename T> auto unwrap(const T& v) -> const T& { return v; }
+template <typename T>
+auto unwrap(const std::reference_wrapper<T>& v) -> const T& {
+  return static_cast<const T&>(v);
+}
+
+// node is defined outside dynamic_arg_list to workaround a C2504 bug in MSVC
+// 2022 (v17.10.0).
+//
+// Workaround for clang's -Wweak-vtables. Unlike for regular classes, for
+// templates it doesn't complain about inability to deduce single translation
+// unit for placing vtable. So node is made a fake template.
+template <typename = void> struct node {
+  virtual ~node() = default;
+  std::unique_ptr<node<>> next;
+};
+
+class dynamic_arg_list {
+  template <typename T> struct typed_node : node<> {
+    T value;
+
+    template <typename Arg>
+    FMT_CONSTEXPR typed_node(const Arg& arg) : value(arg) {}
+
+    template <typename Char>
+    FMT_CONSTEXPR typed_node(const basic_string_view<Char>& arg)
+        : value(arg.data(), arg.size()) {}
+  };
+
+  std::unique_ptr<node<>> head_;
+
+ public:
+  template <typename T, typename Arg> auto push(const Arg& arg) -> const T& {
+    auto new_node = std::unique_ptr<typed_node<T>>(new typed_node<T>(arg));
+    auto& value = new_node->value;
+    new_node->next = std::move(head_);
+    head_ = std::move(new_node);
+    return value;
+  }
+};
+}  // namespace detail
+
+/**
+ * A dynamic list of formatting arguments with storage.
+ *
+ * It can be implicitly converted into `fmt::basic_format_args` for passing
+ * into type-erased formatting functions such as `fmt::vformat`.
+ */
+template <typename Context> class dynamic_format_arg_store {
+ private:
+  using char_type = typename Context::char_type;
+
+  template <typename T> struct need_copy {
+    static constexpr detail::type mapped_type =
+        detail::mapped_type_constant<T, char_type>::value;
+
+    enum {
+      value = !(detail::is_reference_wrapper<T>::value ||
+                std::is_same<T, basic_string_view<char_type>>::value ||
+                std::is_same<T, detail::std_string_view<char_type>>::value ||
+                (mapped_type != detail::type::cstring_type &&
+                 mapped_type != detail::type::string_type &&
+                 mapped_type != detail::type::custom_type))
+    };
+  };
+
+  template <typename T>
+  using stored_t = conditional_t<
+      std::is_convertible<T, std::basic_string<char_type>>::value &&
+          !detail::is_reference_wrapper<T>::value,
+      std::basic_string<char_type>, T>;
+
+  // Storage of basic_format_arg must be contiguous.
+  std::vector<basic_format_arg<Context>> data_;
+  std::vector<detail::named_arg_info<char_type>> named_info_;
+
+  // Storage of arguments not fitting into basic_format_arg must grow
+  // without relocation because items in data_ refer to it.
+  detail::dynamic_arg_list dynamic_args_;
+
+  friend class basic_format_args<Context>;
+
+  auto data() const -> const basic_format_arg<Context>* {
+    return named_info_.empty() ? data_.data() : data_.data() + 1;
+  }
+
+  template <typename T> void emplace_arg(const T& arg) {
+    data_.emplace_back(arg);
+  }
+
+  template <typename T>
+  void emplace_arg(const detail::named_arg<char_type, T>& arg) {
+    if (named_info_.empty())
+      data_.insert(data_.begin(), basic_format_arg<Context>(nullptr, 0));
+    data_.emplace_back(detail::unwrap(arg.value));
+    auto pop_one = [](std::vector<basic_format_arg<Context>>* data) {
+      data->pop_back();
+    };
+    std::unique_ptr<std::vector<basic_format_arg<Context>>, decltype(pop_one)>
+        guard{&data_, pop_one};
+    named_info_.push_back({arg.name, static_cast<int>(data_.size() - 2u)});
+    data_[0] = {named_info_.data(), named_info_.size()};
+    guard.release();
+  }
+
+ public:
+  constexpr dynamic_format_arg_store() = default;
+
+  operator basic_format_args<Context>() const {
+    return basic_format_args<Context>(data(), static_cast<int>(data_.size()),
+                                      !named_info_.empty());
+  }
+
+  /**
+   * Adds an argument into the dynamic store for later passing to a formatting
+   * function.
+   *
+   * Note that custom types and string types (but not string views) are copied
+   * into the store dynamically allocating memory if necessary.
+   *
+   * **Example**:
+   *
+   *     fmt::dynamic_format_arg_store<fmt::format_context> store;
+   *     store.push_back(42);
+   *     store.push_back("abc");
+   *     store.push_back(1.5f);
+   *     std::string result = fmt::vformat("{} and {} and {}", store);
+   */
+  template <typename T> void push_back(const T& arg) {
+    if (detail::const_check(need_copy<T>::value))
+      emplace_arg(dynamic_args_.push<stored_t<T>>(arg));
+    else
+      emplace_arg(detail::unwrap(arg));
+  }
+
+  /**
+   * Adds a reference to the argument into the dynamic store for later passing
+   * to a formatting function.
+   *
+   * **Example**:
+   *
+   *     fmt::dynamic_format_arg_store<fmt::format_context> store;
+   *     char band[] = "Rolling Stones";
+   *     store.push_back(std::cref(band));
+   *     band[9] = 'c'; // Changing str affects the output.
+   *     std::string result = fmt::vformat("{}", store);
+   *     // result == "Rolling Scones"
+   */
+  template <typename T> void push_back(std::reference_wrapper<T> arg) {
+    static_assert(
+        need_copy<T>::value,
+        "objects of built-in types and string views are always copied");
+    emplace_arg(arg.get());
+  }
+
+  /**
+   * Adds named argument into the dynamic store for later passing to a
+   * formatting function. `std::reference_wrapper` is supported to avoid
+   * copying of the argument. The name is always copied into the store.
+   */
+  template <typename T>
+  void push_back(const detail::named_arg<char_type, T>& arg) {
+    const char_type* arg_name =
+        dynamic_args_.push<std::basic_string<char_type>>(arg.name).c_str();
+    if (detail::const_check(need_copy<T>::value)) {
+      emplace_arg(
+          fmt::arg(arg_name, dynamic_args_.push<stored_t<T>>(arg.value)));
+    } else {
+      emplace_arg(fmt::arg(arg_name, arg.value));
+    }
+  }
+
+  /// Erase all elements from the store.
+  void clear() {
+    data_.clear();
+    named_info_.clear();
+    dynamic_args_ = {};
+  }
+
+  /// Reserves space to store at least `new_cap` arguments including
+  /// `new_cap_named` named arguments.
+  void reserve(size_t new_cap, size_t new_cap_named) {
+    FMT_ASSERT(new_cap >= new_cap_named,
+               "set of arguments includes set of named arguments");
+    data_.reserve(new_cap);
+    named_info_.reserve(new_cap_named);
+  }
+
+  /// Returns the number of elements in the store.
+  size_t size() const noexcept { return data_.size(); }
+};
+
+FMT_END_NAMESPACE
+
+#endif  // FMT_ARGS_H_

include/spdlog/fmt/bundled/color.h

@@ -11,6 +11,7 @@
 #include "format.h"
 
 FMT_BEGIN_NAMESPACE
+FMT_BEGIN_EXPORT
 
 enum class color : uint32_t {
   alice_blue = 0xF0F8FF,               // rgb(240,248,255)
@@ -177,19 +178,23 @@ enum class terminal_color : uint8_t {
 
 enum class emphasis : uint8_t {
   bold = 1,
-  italic = 1 << 1,
-  underline = 1 << 2,
-  strikethrough = 1 << 3
+  faint = 1 << 1,
+  italic = 1 << 2,
+  underline = 1 << 3,
+  blink = 1 << 4,
+  reverse = 1 << 5,
+  conceal = 1 << 6,
+  strikethrough = 1 << 7,
 };
 
 // rgb is a struct for red, green and blue colors.
 // Using the name "rgb" makes some editors show the color in a tooltip.
 struct rgb {
-  FMT_CONSTEXPR rgb() : r(0), g(0), b(0) {}
-  FMT_CONSTEXPR rgb(uint8_t r_, uint8_t g_, uint8_t b_) : r(r_), g(g_), b(b_) {}
-  FMT_CONSTEXPR rgb(uint32_t hex)
+  constexpr rgb() : r(0), g(0), b(0) {}
+  constexpr rgb(uint8_t r_, uint8_t g_, uint8_t b_) : r(r_), g(g_), b(b_) {}
+  constexpr rgb(uint32_t hex)
       : r((hex >> 16) & 0xFF), g((hex >> 8) & 0xFF), b(hex & 0xFF) {}
-  FMT_CONSTEXPR rgb(color hex)
+  constexpr rgb(color hex)
       : r((uint32_t(hex) >> 16) & 0xFF),
         g((uint32_t(hex) >> 8) & 0xFF),
         b(uint32_t(hex) & 0xFF) {}
@@ -198,173 +203,179 @@ struct rgb {
   uint8_t b;
 };
 
-namespace internal {
+namespace detail {
 
-// color is a struct of either a rgb color or a terminal color.
+// A bit-packed variant of an RGB color, a terminal color, or unset color.
+// see text_style for the bit-packing scheme.
 struct color_type {
-  FMT_CONSTEXPR color_type() FMT_NOEXCEPT : is_rgb(), value{} {}
-  FMT_CONSTEXPR color_type(color rgb_color) FMT_NOEXCEPT : is_rgb(true),
-                                                           value{} {
-    value.rgb_color = static_cast<uint32_t>(rgb_color);
+  constexpr color_type() noexcept = default;
+  constexpr color_type(color rgb_color) noexcept
+      : value_(static_cast<uint32_t>(rgb_color) | (1 << 24)) {}
+  constexpr color_type(rgb rgb_color) noexcept
+      : color_type(static_cast<color>(
+            (static_cast<uint32_t>(rgb_color.r) << 16) |
+            (static_cast<uint32_t>(rgb_color.g) << 8) | rgb_color.b)) {}
+  constexpr color_type(terminal_color term_color) noexcept
+      : value_(static_cast<uint32_t>(term_color) | (3 << 24)) {}
+
+  constexpr auto is_terminal_color() const noexcept -> bool {
+    return (value_ & (1 << 25)) != 0;
   }
-  FMT_CONSTEXPR color_type(rgb rgb_color) FMT_NOEXCEPT : is_rgb(true), value{} {
-    value.rgb_color = (static_cast<uint32_t>(rgb_color.r) << 16) |
-                      (static_cast<uint32_t>(rgb_color.g) << 8) | rgb_color.b;
+
+  constexpr auto value() const noexcept -> uint32_t {
+    return value_ & 0xFFFFFF;
   }
-  FMT_CONSTEXPR color_type(terminal_color term_color) FMT_NOEXCEPT : is_rgb(),
-                                                                     value{} {
-    value.term_color = static_cast<uint8_t>(term_color);
-  }
-  bool is_rgb;
-  union color_union {
-    uint8_t term_color;
-    uint32_t rgb_color;
-  } value;
+
+  constexpr color_type(uint32_t value) noexcept : value_(value) {}
+
+  uint32_t value_ = 0;
 };
-}  // namespace internal
+}  // namespace detail
 
-// Experimental text formatting support.
+/// A text style consisting of foreground and background colors and emphasis.
 class text_style {
+  // The information is packed as follows:
+  // ┌──┐
+  // │ 0│─┐
+  // │..│ ├── foreground color value
+  // │23│─┘
+  // ├──┤
+  // │24│─┬── discriminator for the above value. 00 if unset, 01 if it's
+  // │25│─┘   an RGB color, or 11 if it's a terminal color (10 is unused)
+  // ├──┤
+  // │26│──── overflow bit, always zero (see below)
+  // ├──┤
+  // │27│─┐
+  // │..│ │
+  // │50│ │
+  // ├──┤ │
+  // │51│ ├── background color (same format as the foreground color)
+  // │52│ │
+  // ├──┤ │
+  // │53│─┘
+  // ├──┤
+  // │54│─┐
+  // │..│ ├── emphases
+  // │61│─┘
+  // ├──┤
+  // │62│─┬── unused
+  // │63│─┘
+  // └──┘
+  // The overflow bits are there to make operator|= efficient.
+  // When ORing, we must throw if, for either the foreground or background,
+  // one style specifies a terminal color and the other specifies any color
+  // (terminal or RGB); in other words, if one discriminator is 11 and the
+  // other is 11 or 01.
+  //
+  // We do that check by adding the styles. Consider what adding does to each
+  // possible pair of discriminators:
+  //    00 + 00 = 000
+  //    01 + 00 = 001
+  //    11 + 00 = 011
+  //    01 + 01 = 010
+  //    11 + 01 = 100 (!!)
+  //    11 + 11 = 110 (!!)
+  // In the last two cases, the ones we want to catch, the third bit——the
+  // overflow bit——is set. Bingo.
+  //
+  // We must take into account the possible carry bit from the bits
+  // before the discriminator. The only potentially problematic case is
+  // 11 + 00 = 011 (a carry bit would make it 100, not good!), but a carry
+  // bit is impossible in that case, because 00 (unset color) means the
+  // 24 bits that precede the discriminator are all zero.
+  //
+  // This test can be applied to both colors simultaneously.
+
  public:
-  FMT_CONSTEXPR text_style(emphasis em = emphasis()) FMT_NOEXCEPT
-      : set_foreground_color(),
-        set_background_color(),
-        ems(em) {}
+  FMT_CONSTEXPR text_style(emphasis em = emphasis()) noexcept
+      : style_(static_cast<uint64_t>(em) << 54) {}
 
-  FMT_CONSTEXPR text_style& operator|=(const text_style& rhs) {
-    if (!set_foreground_color) {
-      set_foreground_color = rhs.set_foreground_color;
-      foreground_color = rhs.foreground_color;
-    } else if (rhs.set_foreground_color) {
-      if (!foreground_color.is_rgb || !rhs.foreground_color.is_rgb)
-        FMT_THROW(format_error("can't OR a terminal color"));
-      foreground_color.value.rgb_color |= rhs.foreground_color.value.rgb_color;
-    }
-
-    if (!set_background_color) {
-      set_background_color = rhs.set_background_color;
-      background_color = rhs.background_color;
-    } else if (rhs.set_background_color) {
-      if (!background_color.is_rgb || !rhs.background_color.is_rgb)
-        FMT_THROW(format_error("can't OR a terminal color"));
-      background_color.value.rgb_color |= rhs.background_color.value.rgb_color;
-    }
-
-    ems = static_cast<emphasis>(static_cast<uint8_t>(ems) |
-                                static_cast<uint8_t>(rhs.ems));
+  FMT_CONSTEXPR auto operator|=(text_style rhs) -> text_style& {
+    if (((style_ + rhs.style_) & ((1ULL << 26) | (1ULL << 53))) != 0)
+      report_error("can't OR a terminal color");
+    style_ |= rhs.style_;
     return *this;
   }
 
-  friend FMT_CONSTEXPR text_style operator|(text_style lhs,
-                                            const text_style& rhs) {
+  friend FMT_CONSTEXPR auto operator|(text_style lhs, text_style rhs)
+      -> text_style {
     return lhs |= rhs;
   }
 
-  FMT_CONSTEXPR text_style& operator&=(const text_style& rhs) {
-    if (!set_foreground_color) {
-      set_foreground_color = rhs.set_foreground_color;
-      foreground_color = rhs.foreground_color;
-    } else if (rhs.set_foreground_color) {
-      if (!foreground_color.is_rgb || !rhs.foreground_color.is_rgb)
-        FMT_THROW(format_error("can't AND a terminal color"));
-      foreground_color.value.rgb_color &= rhs.foreground_color.value.rgb_color;
-    }
-
-    if (!set_background_color) {
-      set_background_color = rhs.set_background_color;
-      background_color = rhs.background_color;
-    } else if (rhs.set_background_color) {
-      if (!background_color.is_rgb || !rhs.background_color.is_rgb)
-        FMT_THROW(format_error("can't AND a terminal color"));
-      background_color.value.rgb_color &= rhs.background_color.value.rgb_color;
-    }
-
-    ems = static_cast<emphasis>(static_cast<uint8_t>(ems) &
-                                static_cast<uint8_t>(rhs.ems));
-    return *this;
+  FMT_CONSTEXPR auto operator==(text_style rhs) const noexcept -> bool {
+    return style_ == rhs.style_;
   }
 
-  friend FMT_CONSTEXPR text_style operator&(text_style lhs,
-                                            const text_style& rhs) {
-    return lhs &= rhs;
+  FMT_CONSTEXPR auto operator!=(text_style rhs) const noexcept -> bool {
+    return !(*this == rhs);
   }
 
-  FMT_CONSTEXPR bool has_foreground() const FMT_NOEXCEPT {
-    return set_foreground_color;
+  FMT_CONSTEXPR auto has_foreground() const noexcept -> bool {
+    return (style_ & (1 << 24)) != 0;
   }
-  FMT_CONSTEXPR bool has_background() const FMT_NOEXCEPT {
-    return set_background_color;
+  FMT_CONSTEXPR auto has_background() const noexcept -> bool {
+    return (style_ & (1ULL << 51)) != 0;
   }
-  FMT_CONSTEXPR bool has_emphasis() const FMT_NOEXCEPT {
-    return static_cast<uint8_t>(ems) != 0;
+  FMT_CONSTEXPR auto has_emphasis() const noexcept -> bool {
+    return (style_ >> 54) != 0;
   }
-  FMT_CONSTEXPR internal::color_type get_foreground() const FMT_NOEXCEPT {
+  FMT_CONSTEXPR auto get_foreground() const noexcept -> detail::color_type {
     FMT_ASSERT(has_foreground(), "no foreground specified for this style");
-    return foreground_color;
+    return style_ & 0x3FFFFFF;
   }
-  FMT_CONSTEXPR internal::color_type get_background() const FMT_NOEXCEPT {
+  FMT_CONSTEXPR auto get_background() const noexcept -> detail::color_type {
     FMT_ASSERT(has_background(), "no background specified for this style");
-    return background_color;
+    return (style_ >> 27) & 0x3FFFFFF;
   }
-  FMT_CONSTEXPR emphasis get_emphasis() const FMT_NOEXCEPT {
+  FMT_CONSTEXPR auto get_emphasis() const noexcept -> emphasis {
     FMT_ASSERT(has_emphasis(), "no emphasis specified for this style");
-    return ems;
+    return static_cast<emphasis>(style_ >> 54);
   }
 
  private:
-  FMT_CONSTEXPR text_style(bool is_foreground,
-                           internal::color_type text_color) FMT_NOEXCEPT
-      : set_foreground_color(),
-        set_background_color(),
-        ems() {
-    if (is_foreground) {
-      foreground_color = text_color;
-      set_foreground_color = true;
-    } else {
-      background_color = text_color;
-      set_background_color = true;
-    }
-  }
+  FMT_CONSTEXPR text_style(uint64_t style) noexcept : style_(style) {}
 
-  friend FMT_CONSTEXPR_DECL text_style fg(internal::color_type foreground)
-      FMT_NOEXCEPT;
-  friend FMT_CONSTEXPR_DECL text_style bg(internal::color_type background)
-      FMT_NOEXCEPT;
+  friend FMT_CONSTEXPR auto fg(detail::color_type foreground) noexcept
+      -> text_style;
 
-  internal::color_type foreground_color;
-  internal::color_type background_color;
-  bool set_foreground_color;
-  bool set_background_color;
-  emphasis ems;
+  friend FMT_CONSTEXPR auto bg(detail::color_type background) noexcept
+      -> text_style;
+
+  uint64_t style_ = 0;
 };
 
-FMT_CONSTEXPR text_style fg(internal::color_type foreground) FMT_NOEXCEPT {
-  return text_style(/*is_foreground=*/true, foreground);
+/// Creates a text style from the foreground (text) color.
+FMT_CONSTEXPR inline auto fg(detail::color_type foreground) noexcept
+    -> text_style {
+  return foreground.value_;
 }
 
-FMT_CONSTEXPR text_style bg(internal::color_type background) FMT_NOEXCEPT {
-  return text_style(/*is_foreground=*/false, background);
+/// Creates a text style from the background color.
+FMT_CONSTEXPR inline auto bg(detail::color_type background) noexcept
+    -> text_style {
+  return static_cast<uint64_t>(background.value_) << 27;
 }
 
-FMT_CONSTEXPR text_style operator|(emphasis lhs, emphasis rhs) FMT_NOEXCEPT {
+FMT_CONSTEXPR inline auto operator|(emphasis lhs, emphasis rhs) noexcept
+    -> text_style {
   return text_style(lhs) | rhs;
 }
 
-namespace internal {
+namespace detail {
 
 template <typename Char> struct ansi_color_escape {
-  FMT_CONSTEXPR ansi_color_escape(internal::color_type text_color,
-                                  const char* esc) FMT_NOEXCEPT {
+  FMT_CONSTEXPR ansi_color_escape(color_type text_color,
+                                  const char* esc) noexcept {
     // If we have a terminal color, we need to output another escape code
     // sequence.
-    if (!text_color.is_rgb) {
-      bool is_background = esc == internal::data::background_color;
-      uint32_t value = text_color.value.term_color;
+    if (text_color.is_terminal_color()) {
+      bool is_background = esc == string_view("\x1b[48;2;");
+      uint32_t value = text_color.value();
       // Background ASCII codes are the same as the foreground ones but with
       // 10 more.
       if (is_background) value += 10u;
 
-      std::size_t index = 0;
+      size_t index = 0;
       buffer[index++] = static_cast<Char>('\x1b');
       buffer[index++] = static_cast<Char>('[');
 
@@ -383,23 +394,25 @@ template <typename Char> struct ansi_color_escape {
     for (int i = 0; i < 7; i++) {
       buffer[i] = static_cast<Char>(esc[i]);
     }
-    rgb color(text_color.value.rgb_color);
+    rgb color(text_color.value());
     to_esc(color.r, buffer + 7, ';');
     to_esc(color.g, buffer + 11, ';');
     to_esc(color.b, buffer + 15, 'm');
     buffer[19] = static_cast<Char>(0);
   }
-  FMT_CONSTEXPR ansi_color_escape(emphasis em) FMT_NOEXCEPT {
-    uint8_t em_codes[4] = {};
-    uint8_t em_bits = static_cast<uint8_t>(em);
-    if (em_bits & static_cast<uint8_t>(emphasis::bold)) em_codes[0] = 1;
-    if (em_bits & static_cast<uint8_t>(emphasis::italic)) em_codes[1] = 3;
-    if (em_bits & static_cast<uint8_t>(emphasis::underline)) em_codes[2] = 4;
-    if (em_bits & static_cast<uint8_t>(emphasis::strikethrough))
-      em_codes[3] = 9;
+  FMT_CONSTEXPR ansi_color_escape(emphasis em) noexcept {
+    uint8_t em_codes[num_emphases] = {};
+    if (has_emphasis(em, emphasis::bold)) em_codes[0] = 1;
+    if (has_emphasis(em, emphasis::faint)) em_codes[1] = 2;
+    if (has_emphasis(em, emphasis::italic)) em_codes[2] = 3;
+    if (has_emphasis(em, emphasis::underline)) em_codes[3] = 4;
+    if (has_emphasis(em, emphasis::blink)) em_codes[4] = 5;
+    if (has_emphasis(em, emphasis::reverse)) em_codes[5] = 7;
+    if (has_emphasis(em, emphasis::conceal)) em_codes[6] = 8;
+    if (has_emphasis(em, emphasis::strikethrough)) em_codes[7] = 9;
 
-    std::size_t index = 0;
-    for (int i = 0; i < 4; ++i) {
+    size_t index = 0;
+    for (size_t i = 0; i < num_emphases; ++i) {
       if (!em_codes[i]) continue;
       buffer[index++] = static_cast<Char>('\x1b');
       buffer[index++] = static_cast<Char>('[');
@@ -408,161 +421,217 @@ template <typename Char> struct ansi_color_escape {
     }
     buffer[index++] = static_cast<Char>(0);
   }
-  FMT_CONSTEXPR operator const Char*() const FMT_NOEXCEPT { return buffer; }
+  FMT_CONSTEXPR operator const Char*() const noexcept { return buffer; }
 
-  FMT_CONSTEXPR const Char* begin() const FMT_NOEXCEPT { return buffer; }
-  FMT_CONSTEXPR const Char* end() const FMT_NOEXCEPT {
-    return buffer + std::char_traits<Char>::length(buffer);
+  FMT_CONSTEXPR auto begin() const noexcept -> const Char* { return buffer; }
+  FMT_CONSTEXPR20 auto end() const noexcept -> const Char* {
+    return buffer + basic_string_view<Char>(buffer).size();
   }
 
  private:
-  Char buffer[7u + 3u * 4u + 1u];
+  static constexpr size_t num_emphases = 8;
+  Char buffer[7u + 3u * num_emphases + 1u];
 
   static FMT_CONSTEXPR void to_esc(uint8_t c, Char* out,
-                                   char delimiter) FMT_NOEXCEPT {
+                                   char delimiter) noexcept {
     out[0] = static_cast<Char>('0' + c / 100);
     out[1] = static_cast<Char>('0' + c / 10 % 10);
     out[2] = static_cast<Char>('0' + c % 10);
     out[3] = static_cast<Char>(delimiter);
   }
+  static FMT_CONSTEXPR auto has_emphasis(emphasis em, emphasis mask) noexcept
+      -> bool {
+    return static_cast<uint8_t>(em) & static_cast<uint8_t>(mask);
+  }
 };
 
 template <typename Char>
-FMT_CONSTEXPR ansi_color_escape<Char> make_foreground_color(
-    internal::color_type foreground) FMT_NOEXCEPT {
-  return ansi_color_escape<Char>(foreground, internal::data::foreground_color);
+FMT_CONSTEXPR auto make_foreground_color(color_type foreground) noexcept
+    -> ansi_color_escape<Char> {
+  return ansi_color_escape<Char>(foreground, "\x1b[38;2;");
 }
 
 template <typename Char>
-FMT_CONSTEXPR ansi_color_escape<Char> make_background_color(
-    internal::color_type background) FMT_NOEXCEPT {
-  return ansi_color_escape<Char>(background, internal::data::background_color);
+FMT_CONSTEXPR auto make_background_color(color_type background) noexcept
+    -> ansi_color_escape<Char> {
+  return ansi_color_escape<Char>(background, "\x1b[48;2;");
 }
 
 template <typename Char>
-FMT_CONSTEXPR ansi_color_escape<Char> make_emphasis(emphasis em) FMT_NOEXCEPT {
+FMT_CONSTEXPR auto make_emphasis(emphasis em) noexcept
+    -> ansi_color_escape<Char> {
   return ansi_color_escape<Char>(em);
 }
 
-template <typename Char>
-inline void fputs(const Char* chars, FILE* stream) FMT_NOEXCEPT {
-  std::fputs(chars, stream);
+template <typename Char> inline void reset_color(buffer<Char>& buffer) {
+  auto reset_color = string_view("\x1b[0m");
+  buffer.append(reset_color.begin(), reset_color.end());
 }
 
-template <>
-inline void fputs<wchar_t>(const wchar_t* chars, FILE* stream) FMT_NOEXCEPT {
-  std::fputws(chars, stream);
-}
-
-template <typename Char> inline void reset_color(FILE* stream) FMT_NOEXCEPT {
-  fputs(internal::data::reset_color, stream);
-}
-
-template <> inline void reset_color<wchar_t>(FILE* stream) FMT_NOEXCEPT {
-  fputs(internal::data::wreset_color, stream);
-}
+template <typename T> struct styled_arg : view {
+  const T& value;
+  text_style style;
+  styled_arg(const T& v, text_style s) : value(v), style(s) {}
+};
 
 template <typename Char>
-inline void reset_color(basic_memory_buffer<Char>& buffer) FMT_NOEXCEPT {
-  const char* begin = data::reset_color;
-  const char* end = begin + sizeof(data::reset_color) - 1;
-  buffer.append(begin, end);
-}
-
-template <typename Char>
-void vformat_to(basic_memory_buffer<Char>& buf, const text_style& ts,
-                basic_string_view<Char> format_str,
-                basic_format_args<buffer_context<Char>> args) {
-  bool has_style = false;
+void vformat_to(buffer<Char>& buf, text_style ts, basic_string_view<Char> fmt,
+                basic_format_args<buffered_context<Char>> args) {
   if (ts.has_emphasis()) {
-    has_style = true;
-    auto emphasis = internal::make_emphasis<Char>(ts.get_emphasis());
+    auto emphasis = make_emphasis<Char>(ts.get_emphasis());
     buf.append(emphasis.begin(), emphasis.end());
   }
   if (ts.has_foreground()) {
-    has_style = true;
-    auto foreground =
-        internal::make_foreground_color<Char>(ts.get_foreground());
+    auto foreground = make_foreground_color<Char>(ts.get_foreground());
     buf.append(foreground.begin(), foreground.end());
   }
   if (ts.has_background()) {
-    has_style = true;
-    auto background =
-        internal::make_background_color<Char>(ts.get_background());
+    auto background = make_background_color<Char>(ts.get_background());
     buf.append(background.begin(), background.end());
   }
-  internal::vformat_to(buf, format_str, args);
-  if (has_style) internal::reset_color<Char>(buf);
+  vformat_to(buf, fmt, args);
+  if (ts != text_style()) reset_color<Char>(buf);
 }
-}  // namespace internal
+}  // namespace detail
 
-template <typename S, typename Char = char_t<S>>
-void vprint(std::FILE* f, const text_style& ts, const S& format,
-            basic_format_args<buffer_context<Char>> args) {
-  basic_memory_buffer<Char> buf;
-  internal::vformat_to(buf, ts, to_string_view(format), args);
-  buf.push_back(Char(0));
-  internal::fputs(buf.data(), f);
+inline void vprint(FILE* f, text_style ts, string_view fmt, format_args args) {
+  auto buf = memory_buffer();
+  detail::vformat_to(buf, ts, fmt, args);
+  print(f, FMT_STRING("{}"), string_view(buf.begin(), buf.size()));
 }
 
 /**
-  Formats a string and prints it to the specified file stream using ANSI
-  escape sequences to specify text formatting.
-  Example:
-    fmt::print(fmt::emphasis::bold | fg(fmt::color::red),
-               "Elapsed time: {0:.2f} seconds", 1.23);
+ * Formats a string and prints it to the specified file stream using ANSI
+ * escape sequences to specify text formatting.
+ *
+ * **Example**:
+ *
+ *     fmt::print(fmt::emphasis::bold | fg(fmt::color::red),
+ *                "Elapsed time: {0:.2f} seconds", 1.23);
  */
-template <typename S, typename... Args,
-          FMT_ENABLE_IF(internal::is_string<S>::value)>
-void print(std::FILE* f, const text_style& ts, const S& format_str,
-           const Args&... args) {
-  internal::check_format_string<Args...>(format_str);
-  using context = buffer_context<char_t<S>>;
-  format_arg_store<context, Args...> as{args...};
-  vprint(f, ts, format_str, basic_format_args<context>(as));
+template <typename... T>
+void print(FILE* f, text_style ts, format_string<T...> fmt, T&&... args) {
+  vprint(f, ts, fmt.str, vargs<T...>{{args...}});
 }
 
 /**
-  Formats a string and prints it to stdout using ANSI escape sequences to
-  specify text formatting.
-  Example:
-    fmt::print(fmt::emphasis::bold | fg(fmt::color::red),
-               "Elapsed time: {0:.2f} seconds", 1.23);
+ * Formats a string and prints it to stdout using ANSI escape sequences to
+ * specify text formatting.
+ *
+ * **Example**:
+ *
+ *     fmt::print(fmt::emphasis::bold | fg(fmt::color::red),
+ *                "Elapsed time: {0:.2f} seconds", 1.23);
  */
-template <typename S, typename... Args,
-          FMT_ENABLE_IF(internal::is_string<S>::value)>
-void print(const text_style& ts, const S& format_str, const Args&... args) {
-  return print(stdout, ts, format_str, args...);
+template <typename... T>
+void print(text_style ts, format_string<T...> fmt, T&&... args) {
+  return print(stdout, ts, fmt, std::forward<T>(args)...);
 }
 
-template <typename S, typename Char = char_t<S>>
-inline std::basic_string<Char> vformat(
-    const text_style& ts, const S& format_str,
-    basic_format_args<buffer_context<type_identity_t<Char>>> args) {
-  basic_memory_buffer<Char> buf;
-  internal::vformat_to(buf, ts, to_string_view(format_str), args);
+inline auto vformat(text_style ts, string_view fmt, format_args args)
+    -> std::string {
+  auto buf = memory_buffer();
+  detail::vformat_to(buf, ts, fmt, args);
   return fmt::to_string(buf);
 }
 
 /**
-  \rst
-  Formats arguments and returns the result as a string using ANSI
-  escape sequences to specify text formatting.
-
-  **Example**::
-
-    #include <fmt/color.h>
-    std::string message = fmt::format(fmt::emphasis::bold | fg(fmt::color::red),
-                                      "The answer is {}", 42);
-  \endrst
-*/
-template <typename S, typename... Args, typename Char = char_t<S>>
-inline std::basic_string<Char> format(const text_style& ts, const S& format_str,
-                                      const Args&... args) {
-  return vformat(ts, to_string_view(format_str),
-                 internal::make_args_checked<Args...>(format_str, args...));
+ * Formats arguments and returns the result as a string using ANSI escape
+ * sequences to specify text formatting.
+ *
+ * **Example**:
+ *
+ * ```
+ * #include <fmt/color.h>
+ * std::string message = fmt::format(fmt::emphasis::bold | fg(fmt::color::red),
+ *                                   "The answer is {}", 42);
+ * ```
+ */
+template <typename... T>
+inline auto format(text_style ts, format_string<T...> fmt, T&&... args)
+    -> std::string {
+  return fmt::vformat(ts, fmt.str, vargs<T...>{{args...}});
 }
 
+/// Formats a string with the given text_style and writes the output to `out`.
+template <typename OutputIt,
+          FMT_ENABLE_IF(detail::is_output_iterator<OutputIt, char>::value)>
+auto vformat_to(OutputIt out, text_style ts, string_view fmt, format_args args)
+    -> OutputIt {
+  auto&& buf = detail::get_buffer<char>(out);
+  detail::vformat_to(buf, ts, fmt, args);
+  return detail::get_iterator(buf, out);
+}
+
+/**
+ * Formats arguments with the given text style, writes the result to the output
+ * iterator `out` and returns the iterator past the end of the output range.
+ *
+ * **Example**:
+ *
+ *     std::vector<char> out;
+ *     fmt::format_to(std::back_inserter(out),
+ *                    fmt::emphasis::bold | fg(fmt::color::red), "{}", 42);
+ */
+template <typename OutputIt, typename... T,
+          FMT_ENABLE_IF(detail::is_output_iterator<OutputIt, char>::value)>
+inline auto format_to(OutputIt out, text_style ts, format_string<T...> fmt,
+                      T&&... args) -> OutputIt {
+  return vformat_to(out, ts, fmt.str, vargs<T...>{{args...}});
+}
+
+template <typename T, typename Char>
+struct formatter<detail::styled_arg<T>, Char> : formatter<T, Char> {
+  template <typename FormatContext>
+  auto format(const detail::styled_arg<T>& arg, FormatContext& ctx) const
+      -> decltype(ctx.out()) {
+    const auto& ts = arg.style;
+    auto out = ctx.out();
+
+    bool has_style = false;
+    if (ts.has_emphasis()) {
+      has_style = true;
+      auto emphasis = detail::make_emphasis<Char>(ts.get_emphasis());
+      out = detail::copy<Char>(emphasis.begin(), emphasis.end(), out);
+    }
+    if (ts.has_foreground()) {
+      has_style = true;
+      auto foreground =
+          detail::make_foreground_color<Char>(ts.get_foreground());
+      out = detail::copy<Char>(foreground.begin(), foreground.end(), out);
+    }
+    if (ts.has_background()) {
+      has_style = true;
+      auto background =
+          detail::make_background_color<Char>(ts.get_background());
+      out = detail::copy<Char>(background.begin(), background.end(), out);
+    }
+    out = formatter<T, Char>::format(arg.value, ctx);
+    if (has_style) {
+      auto reset_color = string_view("\x1b[0m");
+      out = detail::copy<Char>(reset_color.begin(), reset_color.end(), out);
+    }
+    return out;
+  }
+};
+
+/**
+ * Returns an argument that will be formatted using ANSI escape sequences,
+ * to be used in a formatting function.
+ *
+ * **Example**:
+ *
+ *     fmt::print("Elapsed time: {0:.2f} seconds",
+ *                fmt::styled(1.23, fmt::fg(fmt::color::green) |
+ *                                  fmt::bg(fmt::color::blue)));
+ */
+template <typename T>
+FMT_CONSTEXPR auto styled(const T& value, text_style ts)
+    -> detail::styled_arg<remove_cvref_t<T>> {
+  return detail::styled_arg<remove_cvref_t<T>>{value, ts};
+}
+
+FMT_END_EXPORT
 FMT_END_NAMESPACE
 
 #endif  // FMT_COLOR_H_

include/spdlog/fmt/bundled/compile.h

@@ -8,344 +8,92 @@
 #ifndef FMT_COMPILE_H_
 #define FMT_COMPILE_H_
 
-#include <vector>
+#ifndef FMT_MODULE
+#  include <iterator>  // std::back_inserter
+#endif
 
 #include "format.h"
 
 FMT_BEGIN_NAMESPACE
-namespace internal {
 
-// Part of a compiled format string. It can be either literal text or a
-// replacement field.
-template <typename Char> struct format_part {
-  enum class kind { arg_index, arg_name, text, replacement };
-
-  struct replacement {
-    arg_ref<Char> arg_id;
-    dynamic_format_specs<Char> specs;
-  };
-
-  kind part_kind;
-  union value {
-    int arg_index;
-    basic_string_view<Char> str;
-    replacement repl;
-
-    FMT_CONSTEXPR value(int index = 0) : arg_index(index) {}
-    FMT_CONSTEXPR value(basic_string_view<Char> s) : str(s) {}
-    FMT_CONSTEXPR value(replacement r) : repl(r) {}
-  } val;
-  // Position past the end of the argument id.
-  const Char* arg_id_end = nullptr;
-
-  FMT_CONSTEXPR format_part(kind k = kind::arg_index, value v = {})
-      : part_kind(k), val(v) {}
-
-  static FMT_CONSTEXPR format_part make_arg_index(int index) {
-    return format_part(kind::arg_index, index);
-  }
-  static FMT_CONSTEXPR format_part make_arg_name(basic_string_view<Char> name) {
-    return format_part(kind::arg_name, name);
-  }
-  static FMT_CONSTEXPR format_part make_text(basic_string_view<Char> text) {
-    return format_part(kind::text, text);
-  }
-  static FMT_CONSTEXPR format_part make_replacement(replacement repl) {
-    return format_part(kind::replacement, repl);
-  }
-};
-
-template <typename Char> struct part_counter {
-  unsigned num_parts = 0;
-
-  FMT_CONSTEXPR void on_text(const Char* begin, const Char* end) {
-    if (begin != end) ++num_parts;
-  }
-
-  FMT_CONSTEXPR void on_arg_id() { ++num_parts; }
-  FMT_CONSTEXPR void on_arg_id(int) { ++num_parts; }
-  FMT_CONSTEXPR void on_arg_id(basic_string_view<Char>) { ++num_parts; }
-
-  FMT_CONSTEXPR void on_replacement_field(const Char*) {}
-
-  FMT_CONSTEXPR const Char* on_format_specs(const Char* begin,
-                                            const Char* end) {
-    // Find the matching brace.
-    unsigned brace_counter = 0;
-    for (; begin != end; ++begin) {
-      if (*begin == '{') {
-        ++brace_counter;
-      } else if (*begin == '}') {
-        if (brace_counter == 0u) break;
-        --brace_counter;
-      }
-    }
-    return begin;
-  }
-
-  FMT_CONSTEXPR void on_error(const char*) {}
-};
-
-// Counts the number of parts in a format string.
-template <typename Char>
-FMT_CONSTEXPR unsigned count_parts(basic_string_view<Char> format_str) {
-  part_counter<Char> counter;
-  parse_format_string<true>(format_str, counter);
-  return counter.num_parts;
-}
-
-template <typename Char, typename PartHandler>
-class format_string_compiler : public error_handler {
- private:
-  using part = format_part<Char>;
-
-  PartHandler handler_;
-  part part_;
-  basic_string_view<Char> format_str_;
-  basic_format_parse_context<Char> parse_context_;
-
- public:
-  FMT_CONSTEXPR format_string_compiler(basic_string_view<Char> format_str,
-                                       PartHandler handler)
-      : handler_(handler),
-        format_str_(format_str),
-        parse_context_(format_str) {}
-
-  FMT_CONSTEXPR void on_text(const Char* begin, const Char* end) {
-    if (begin != end)
-      handler_(part::make_text({begin, to_unsigned(end - begin)}));
-  }
-
-  FMT_CONSTEXPR void on_arg_id() {
-    part_ = part::make_arg_index(parse_context_.next_arg_id());
-  }
-
-  FMT_CONSTEXPR void on_arg_id(int id) {
-    parse_context_.check_arg_id(id);
-    part_ = part::make_arg_index(id);
-  }
-
-  FMT_CONSTEXPR void on_arg_id(basic_string_view<Char> id) {
-    part_ = part::make_arg_name(id);
-  }
-
-  FMT_CONSTEXPR void on_replacement_field(const Char* ptr) {
-    part_.arg_id_end = ptr;
-    handler_(part_);
-  }
-
-  FMT_CONSTEXPR const Char* on_format_specs(const Char* begin,
-                                            const Char* end) {
-    auto repl = typename part::replacement();
-    dynamic_specs_handler<basic_format_parse_context<Char>> handler(
-        repl.specs, parse_context_);
-    auto it = parse_format_specs(begin, end, handler);
-    if (*it != '}') on_error("missing '}' in format string");
-    repl.arg_id = part_.part_kind == part::kind::arg_index
-                      ? arg_ref<Char>(part_.val.arg_index)
-                      : arg_ref<Char>(part_.val.str);
-    auto part = part::make_replacement(repl);
-    part.arg_id_end = begin;
-    handler_(part);
-    return it;
-  }
-};
-
-// Compiles a format string and invokes handler(part) for each parsed part.
-template <bool IS_CONSTEXPR, typename Char, typename PartHandler>
-FMT_CONSTEXPR void compile_format_string(basic_string_view<Char> format_str,
-                                         PartHandler handler) {
-  parse_format_string<IS_CONSTEXPR>(
-      format_str,
-      format_string_compiler<Char, PartHandler>(format_str, handler));
-}
-
-template <typename Range, typename Context, typename Id>
-void format_arg(
-    basic_format_parse_context<typename Range::value_type>& parse_ctx,
-    Context& ctx, Id arg_id) {
-  ctx.advance_to(
-      visit_format_arg(arg_formatter<Range>(ctx, &parse_ctx), ctx.arg(arg_id)));
-}
-
-// vformat_to is defined in a subnamespace to prevent ADL.
-namespace cf {
-template <typename Context, typename Range, typename CompiledFormat>
-auto vformat_to(Range out, CompiledFormat& cf, basic_format_args<Context> args)
-    -> typename Context::iterator {
-  using char_type = typename Context::char_type;
-  basic_format_parse_context<char_type> parse_ctx(
-      to_string_view(cf.format_str_));
-  Context ctx(out.begin(), args);
-
-  const auto& parts = cf.parts();
-  for (auto part_it = std::begin(parts); part_it != std::end(parts);
-       ++part_it) {
-    const auto& part = *part_it;
-    const auto& value = part.val;
-
-    using format_part_t = format_part<char_type>;
-    switch (part.part_kind) {
-    case format_part_t::kind::text: {
-      const auto text = value.str;
-      auto output = ctx.out();
-      auto&& it = reserve(output, text.size());
-      it = std::copy_n(text.begin(), text.size(), it);
-      ctx.advance_to(output);
-      break;
-    }
-
-    case format_part_t::kind::arg_index:
-      advance_to(parse_ctx, part.arg_id_end);
-      internal::format_arg<Range>(parse_ctx, ctx, value.arg_index);
-      break;
-
-    case format_part_t::kind::arg_name:
-      advance_to(parse_ctx, part.arg_id_end);
-      internal::format_arg<Range>(parse_ctx, ctx, value.str);
-      break;
-
-    case format_part_t::kind::replacement: {
-      const auto& arg_id_value = value.repl.arg_id.val;
-      const auto arg = value.repl.arg_id.kind == arg_id_kind::index
-                           ? ctx.arg(arg_id_value.index)
-                           : ctx.arg(arg_id_value.name);
-
-      auto specs = value.repl.specs;
-
-      handle_dynamic_spec<width_checker>(specs.width, specs.width_ref, ctx);
-      handle_dynamic_spec<precision_checker>(specs.precision,
-                                             specs.precision_ref, ctx);
-
-      error_handler h;
-      numeric_specs_checker<error_handler> checker(h, arg.type());
-      if (specs.align == align::numeric) checker.require_numeric_argument();
-      if (specs.sign != sign::none) checker.check_sign();
-      if (specs.alt) checker.require_numeric_argument();
-      if (specs.precision >= 0) checker.check_precision();
-
-      advance_to(parse_ctx, part.arg_id_end);
-      ctx.advance_to(
-          visit_format_arg(arg_formatter<Range>(ctx, nullptr, &specs), arg));
-      break;
-    }
-    }
-  }
-  return ctx.out();
-}
-}  // namespace cf
-
-struct basic_compiled_format {};
-
-template <typename S, typename = void>
-struct compiled_format_base : basic_compiled_format {
-  using char_type = char_t<S>;
-  using parts_container = std::vector<internal::format_part<char_type>>;
-
-  parts_container compiled_parts;
-
-  explicit compiled_format_base(basic_string_view<char_type> format_str) {
-    compile_format_string<false>(format_str,
-                                 [this](const format_part<char_type>& part) {
-                                   compiled_parts.push_back(part);
-                                 });
-  }
-
-  const parts_container& parts() const { return compiled_parts; }
-};
-
-template <typename Char, unsigned N> struct format_part_array {
-  format_part<Char> data[N] = {};
-  FMT_CONSTEXPR format_part_array() = default;
-};
-
-template <typename Char, unsigned N>
-FMT_CONSTEXPR format_part_array<Char, N> compile_to_parts(
-    basic_string_view<Char> format_str) {
-  format_part_array<Char, N> parts;
-  unsigned counter = 0;
-  // This is not a lambda for compatibility with older compilers.
-  struct {
-    format_part<Char>* parts;
-    unsigned* counter;
-    FMT_CONSTEXPR void operator()(const format_part<Char>& part) {
-      parts[(*counter)++] = part;
-    }
-  } collector{parts.data, &counter};
-  compile_format_string<true>(format_str, collector);
-  if (counter < N) {
-    parts.data[counter] =
-        format_part<Char>::make_text(basic_string_view<Char>());
-  }
-  return parts;
-}
-
-template <typename T> constexpr const T& constexpr_max(const T& a, const T& b) {
-  return (a < b) ? b : a;
-}
+// A compile-time string which is compiled into fast formatting code.
+FMT_EXPORT class compiled_string {};
 
 template <typename S>
-struct compiled_format_base<S, enable_if_t<is_compile_string<S>::value>>
-    : basic_compiled_format {
-  using char_type = char_t<S>;
+struct is_compiled_string : std::is_base_of<compiled_string, S> {};
 
-  FMT_CONSTEXPR explicit compiled_format_base(basic_string_view<char_type>) {}
+namespace detail {
 
-// Workaround for old compilers. Format string compilation will not be
-// performed there anyway.
-#if FMT_USE_CONSTEXPR
-  static FMT_CONSTEXPR_DECL const unsigned num_format_parts =
-      constexpr_max(count_parts(to_string_view(S())), 1u);
+/**
+ * Converts a string literal `s` into a format string that will be parsed at
+ * compile time and converted into efficient formatting code. Requires C++17
+ * `constexpr if` compiler support.
+ *
+ * **Example**:
+ *
+ *     // Converts 42 into std::string using the most efficient method and no
+ *     // runtime format string processing.
+ *     std::string s = fmt::format(FMT_COMPILE("{}"), 42);
+ */
+#if defined(__cpp_if_constexpr) && defined(__cpp_return_type_deduction)
+#  define FMT_COMPILE(s) FMT_STRING_IMPL(s, fmt::compiled_string)
 #else
-  static const unsigned num_format_parts = 1;
+#  define FMT_COMPILE(s) FMT_STRING(s)
 #endif
 
-  using parts_container = format_part<char_type>[num_format_parts];
+template <typename T, typename... Tail>
+auto first(const T& value, const Tail&...) -> const T& {
+  return value;
+}
 
-  const parts_container& parts() const {
-    static FMT_CONSTEXPR_DECL const auto compiled_parts =
-        compile_to_parts<char_type, num_format_parts>(
-            internal::to_string_view(S()));
-    return compiled_parts.data;
-  }
-};
-
-template <typename S, typename... Args>
-class compiled_format : private compiled_format_base<S> {
- public:
-  using typename compiled_format_base<S>::char_type;
-
- private:
-  basic_string_view<char_type> format_str_;
-
-  template <typename Context, typename Range, typename CompiledFormat>
-  friend auto cf::vformat_to(Range out, CompiledFormat& cf,
-                             basic_format_args<Context> args) ->
-      typename Context::iterator;
-
- public:
-  compiled_format() = delete;
-  explicit constexpr compiled_format(basic_string_view<char_type> format_str)
-      : compiled_format_base<S>(format_str), format_str_(format_str) {}
-};
-
-#ifdef __cpp_if_constexpr
+#if defined(__cpp_if_constexpr) && defined(__cpp_return_type_deduction)
 template <typename... Args> struct type_list {};
 
 // Returns a reference to the argument at index N from [first, rest...].
 template <int N, typename T, typename... Args>
-constexpr const auto& get(const T& first, const Args&... rest) {
+constexpr const auto& get([[maybe_unused]] const T& first,
+                          [[maybe_unused]] const Args&... rest) {
   static_assert(N < 1 + sizeof...(Args), "index is out of bounds");
   if constexpr (N == 0)
     return first;
   else
-    return get<N - 1>(rest...);
+    return detail::get<N - 1>(rest...);
+}
+
+#  if FMT_USE_NONTYPE_TEMPLATE_ARGS
+template <int N, typename T, typename... Args, typename Char>
+constexpr auto get_arg_index_by_name(basic_string_view<Char> name) -> int {
+  if constexpr (is_static_named_arg<T>()) {
+    if (name == T::name) return N;
+  }
+  if constexpr (sizeof...(Args) > 0)
+    return get_arg_index_by_name<N + 1, Args...>(name);
+  (void)name;  // Workaround an MSVC bug about "unused" parameter.
+  return -1;
+}
+#  endif
+
+template <typename... Args, typename Char>
+FMT_CONSTEXPR auto get_arg_index_by_name(basic_string_view<Char> name) -> int {
+#  if FMT_USE_NONTYPE_TEMPLATE_ARGS
+  if constexpr (sizeof...(Args) > 0)
+    return get_arg_index_by_name<0, Args...>(name);
+#  endif
+  (void)name;
+  return -1;
+}
+
+template <typename Char, typename... Args>
+constexpr int get_arg_index_by_name(basic_string_view<Char> name,
+                                    type_list<Args...>) {
+  return get_arg_index_by_name<Args...>(name);
 }
 
 template <int N, typename> struct get_type_impl;
 
 template <int N, typename... Args> struct get_type_impl<N, type_list<Args...>> {
-  using type = remove_cvref_t<decltype(get<N>(std::declval<Args>()...))>;
+  using type =
+      remove_cvref_t<decltype(detail::get<N>(std::declval<Args>()...))>;
 };
 
 template <int N, typename T>
@@ -358,9 +106,8 @@ template <typename Char> struct text {
   using char_type = Char;
 
   template <typename OutputIt, typename... Args>
-  OutputIt format(OutputIt out, const Args&...) const {
-    // TODO: reserve
-    return copy_str<Char>(data.begin(), data.end(), out);
+  constexpr OutputIt format(OutputIt out, const Args&...) const {
+    return write<Char>(out, data);
   }
 };
 
@@ -373,55 +120,107 @@ constexpr text<Char> make_text(basic_string_view<Char> s, size_t pos,
   return {{&s[pos], size}};
 }
 
-template <typename Char, typename OutputIt, typename T,
-          std::enable_if_t<std::is_integral_v<T>, int> = 0>
-OutputIt format_default(OutputIt out, T value) {
-  // TODO: reserve
-  format_int fi(value);
-  return std::copy(fi.data(), fi.data() + fi.size(), out);
+template <typename Char> struct code_unit {
+  Char value;
+  using char_type = Char;
+
+  template <typename OutputIt, typename... Args>
+  constexpr OutputIt format(OutputIt out, const Args&...) const {
+    *out++ = value;
+    return out;
+  }
+};
+
+// This ensures that the argument type is convertible to `const T&`.
+template <typename T, int N, typename... Args>
+constexpr const T& get_arg_checked(const Args&... args) {
+  const auto& arg = detail::get<N>(args...);
+  if constexpr (detail::is_named_arg<remove_cvref_t<decltype(arg)>>()) {
+    return arg.value;
+  } else {
+    return arg;
+  }
 }
 
-template <typename Char, typename OutputIt>
-OutputIt format_default(OutputIt out, double value) {
-  writer w(out);
-  w.write(value);
-  return w.out();
-}
-
-template <typename Char, typename OutputIt>
-OutputIt format_default(OutputIt out, Char value) {
-  *out++ = value;
-  return out;
-}
-
-template <typename Char, typename OutputIt>
-OutputIt format_default(OutputIt out, const Char* value) {
-  auto length = std::char_traits<Char>::length(value);
-  return copy_str<Char>(value, value + length, out);
-}
+template <typename Char>
+struct is_compiled_format<code_unit<Char>> : std::true_type {};
 
 // A replacement field that refers to argument N.
 template <typename Char, typename T, int N> struct field {
   using char_type = Char;
 
   template <typename OutputIt, typename... Args>
-  OutputIt format(OutputIt out, const Args&... args) const {
-    // This ensures that the argument type is convertile to `const T&`.
-    const T& arg = get<N>(args...);
-    return format_default<Char>(out, arg);
+  constexpr OutputIt format(OutputIt out, const Args&... args) const {
+    const T& arg = get_arg_checked<T, N>(args...);
+    if constexpr (std::is_convertible<T, basic_string_view<Char>>::value) {
+      auto s = basic_string_view<Char>(arg);
+      return copy<Char>(s.begin(), s.end(), out);
+    } else {
+      return write<Char>(out, arg);
+    }
   }
 };
 
 template <typename Char, typename T, int N>
 struct is_compiled_format<field<Char, T, N>> : std::true_type {};
 
+// A replacement field that refers to argument with name.
+template <typename Char> struct runtime_named_field {
+  using char_type = Char;
+  basic_string_view<Char> name;
+
+  template <typename OutputIt, typename T>
+  constexpr static bool try_format_argument(
+      OutputIt& out,
+      // [[maybe_unused]] due to unused-but-set-parameter warning in GCC 7,8,9
+      [[maybe_unused]] basic_string_view<Char> arg_name, const T& arg) {
+    if constexpr (is_named_arg<typename std::remove_cv<T>::type>::value) {
+      if (arg_name == arg.name) {
+        out = write<Char>(out, arg.value);
+        return true;
+      }
+    }
+    return false;
+  }
+
+  template <typename OutputIt, typename... Args>
+  constexpr OutputIt format(OutputIt out, const Args&... args) const {
+    bool found = (try_format_argument(out, name, args) || ...);
+    if (!found) {
+      FMT_THROW(format_error("argument with specified name is not found"));
+    }
+    return out;
+  }
+};
+
+template <typename Char>
+struct is_compiled_format<runtime_named_field<Char>> : std::true_type {};
+
+// A replacement field that refers to argument N and has format specifiers.
+template <typename Char, typename T, int N> struct spec_field {
+  using char_type = Char;
+  formatter<T, Char> fmt;
+
+  template <typename OutputIt, typename... Args>
+  constexpr FMT_INLINE OutputIt format(OutputIt out,
+                                       const Args&... args) const {
+    const auto& vargs =
+        fmt::make_format_args<basic_format_context<OutputIt, Char>>(args...);
+    basic_format_context<OutputIt, Char> ctx(out, vargs);
+    return fmt.format(get_arg_checked<T, N>(args...), ctx);
+  }
+};
+
+template <typename Char, typename T, int N>
+struct is_compiled_format<spec_field<Char, T, N>> : std::true_type {};
+
 template <typename L, typename R> struct concat {
   L lhs;
   R rhs;
   using char_type = typename L::char_type;
 
   template <typename OutputIt, typename... Args>
-  OutputIt format(OutputIt out, const Args&... args) const {
+  constexpr OutputIt format(OutputIt out, const Args&... args) const {
     out = lhs.format(out, args...);
     return rhs.format(out, args...);
   }
@@ -446,12 +245,12 @@ constexpr size_t parse_text(basic_string_view<Char> str, size_t pos) {
 }
 
 template <typename Args, size_t POS, int ID, typename S>
-constexpr auto compile_format_string(S format_str);
+constexpr auto compile_format_string(S fmt);
 
 template <typename Args, size_t POS, int ID, typename T, typename S>
-constexpr auto parse_tail(T head, S format_str) {
-  if constexpr (POS != to_string_view(format_str).size()) {
-    constexpr auto tail = compile_format_string<Args, POS, ID>(format_str);
+constexpr auto parse_tail(T head, S fmt) {
+  if constexpr (POS != basic_string_view<typename S::char_type>(fmt).size()) {
+    constexpr auto tail = compile_format_string<Args, POS, ID>(fmt);
     if constexpr (std::is_same<remove_cvref_t<decltype(tail)>,
                                unknown_format>())
       return tail;
@@ -462,134 +261,279 @@ constexpr auto parse_tail(T head, S format_str) {
   }
 }
 
+template <typename T, typename Char> struct parse_specs_result {
+  formatter<T, Char> fmt;
+  size_t end;
+  int next_arg_id;
+};
+
+enum { manual_indexing_id = -1 };
+
+template <typename T, typename Char>
+constexpr parse_specs_result<T, Char> parse_specs(basic_string_view<Char> str,
+                                                  size_t pos, int next_arg_id) {
+  str.remove_prefix(pos);
+  auto ctx =
+      compile_parse_context<Char>(str, max_value<int>(), nullptr, next_arg_id);
+  auto f = formatter<T, Char>();
+  auto end = f.parse(ctx);
+  return {f, pos + fmt::detail::to_unsigned(end - str.data()),
+          next_arg_id == 0 ? manual_indexing_id : ctx.next_arg_id()};
+}
+
+template <typename Char> struct arg_id_handler {
+  arg_id_kind kind;
+  arg_ref<Char> arg_id;
+
+  constexpr int on_auto() {
+    FMT_ASSERT(false, "handler cannot be used with automatic indexing");
+    return 0;
+  }
+  constexpr int on_index(int id) {
+    kind = arg_id_kind::index;
+    arg_id = arg_ref<Char>(id);
+    return 0;
+  }
+  constexpr int on_name(basic_string_view<Char> id) {
+    kind = arg_id_kind::name;
+    arg_id = arg_ref<Char>(id);
+    return 0;
+  }
+};
+
+template <typename Char> struct parse_arg_id_result {
+  arg_id_kind kind;
+  arg_ref<Char> arg_id;
+  const Char* arg_id_end;
+};
+
+template <int ID, typename Char>
+constexpr auto parse_arg_id(const Char* begin, const Char* end) {
+  auto handler = arg_id_handler<Char>{arg_id_kind::none, arg_ref<Char>{}};
+  auto arg_id_end = parse_arg_id(begin, end, handler);
+  return parse_arg_id_result<Char>{handler.kind, handler.arg_id, arg_id_end};
+}
+
+template <typename T, typename Enable = void> struct field_type {
+  using type = remove_cvref_t<T>;
+};
+
+template <typename T>
+struct field_type<T, enable_if_t<detail::is_named_arg<T>::value>> {
+  using type = remove_cvref_t<decltype(T::value)>;
+};
+
+template <typename T, typename Args, size_t END_POS, int ARG_INDEX, int NEXT_ID,
+          typename S>
+constexpr auto parse_replacement_field_then_tail(S fmt) {
+  using char_type = typename S::char_type;
+  constexpr auto str = basic_string_view<char_type>(fmt);
+  constexpr char_type c = END_POS != str.size() ? str[END_POS] : char_type();
+  if constexpr (c == '}') {
+    return parse_tail<Args, END_POS + 1, NEXT_ID>(
+        field<char_type, typename field_type<T>::type, ARG_INDEX>(), fmt);
+  } else if constexpr (c != ':') {
+    FMT_THROW(format_error("expected ':'"));
+  } else {
+    constexpr auto result = parse_specs<typename field_type<T>::type>(
+        str, END_POS + 1, NEXT_ID == manual_indexing_id ? 0 : NEXT_ID);
+    if constexpr (result.end >= str.size() || str[result.end] != '}') {
+      FMT_THROW(format_error("expected '}'"));
+      return 0;
+    } else {
+      return parse_tail<Args, result.end + 1, result.next_arg_id>(
+          spec_field<char_type, typename field_type<T>::type, ARG_INDEX>{
+              result.fmt},
+          fmt);
+    }
+  }
+}
+
 // Compiles a non-empty format string and returns the compiled representation
 // or unknown_format() on unrecognized input.
 template <typename Args, size_t POS, int ID, typename S>
-constexpr auto compile_format_string(S format_str) {
+constexpr auto compile_format_string(S fmt) {
   using char_type = typename S::char_type;
-  constexpr basic_string_view<char_type> str = format_str;
+  constexpr auto str = basic_string_view<char_type>(fmt);
   if constexpr (str[POS] == '{') {
-    if (POS + 1 == str.size())
-      throw format_error("unmatched '{' in format string");
+    if constexpr (POS + 1 == str.size())
+      FMT_THROW(format_error("unmatched '{' in format string"));
     if constexpr (str[POS + 1] == '{') {
-      return parse_tail<Args, POS + 2, ID>(make_text(str, POS, 1), format_str);
-    } else if constexpr (str[POS + 1] == '}') {
-      using type = get_type<ID, Args>;
-      if constexpr (std::is_same<type, int>::value) {
-        return parse_tail<Args, POS + 2, ID + 1>(field<char_type, type, ID>(),
-                                                 format_str);
-      } else {
-        return unknown_format();
-      }
+      return parse_tail<Args, POS + 2, ID>(make_text(str, POS, 1), fmt);
+    } else if constexpr (str[POS + 1] == '}' || str[POS + 1] == ':') {
+      static_assert(ID != manual_indexing_id,
+                    "cannot switch from manual to automatic argument indexing");
+      constexpr auto next_id =
+          ID != manual_indexing_id ? ID + 1 : manual_indexing_id;
+      return parse_replacement_field_then_tail<get_type<ID, Args>, Args,
+                                               POS + 1, ID, next_id>(fmt);
     } else {
-      return unknown_format();
+      constexpr auto arg_id_result =
+          parse_arg_id<ID>(str.data() + POS + 1, str.data() + str.size());
+      constexpr auto arg_id_end_pos = arg_id_result.arg_id_end - str.data();
+      constexpr char_type c =
+          arg_id_end_pos != str.size() ? str[arg_id_end_pos] : char_type();
+      static_assert(c == '}' || c == ':', "missing '}' in format string");
+      if constexpr (arg_id_result.kind == arg_id_kind::index) {
+        static_assert(
+            ID == manual_indexing_id || ID == 0,
+            "cannot switch from automatic to manual argument indexing");
+        constexpr auto arg_index = arg_id_result.arg_id.index;
+        return parse_replacement_field_then_tail<get_type<arg_index, Args>,
+                                                 Args, arg_id_end_pos,
+                                                 arg_index, manual_indexing_id>(
+            fmt);
+      } else if constexpr (arg_id_result.kind == arg_id_kind::name) {
+        constexpr auto arg_index =
+            get_arg_index_by_name(arg_id_result.arg_id.name, Args{});
+        if constexpr (arg_index >= 0) {
+          constexpr auto next_id =
+              ID != manual_indexing_id ? ID + 1 : manual_indexing_id;
+          return parse_replacement_field_then_tail<
+              decltype(get_type<arg_index, Args>::value), Args, arg_id_end_pos,
+              arg_index, next_id>(fmt);
+        } else if constexpr (c == '}') {
+          return parse_tail<Args, arg_id_end_pos + 1, ID>(
+              runtime_named_field<char_type>{arg_id_result.arg_id.name}, fmt);
+        } else if constexpr (c == ':') {
+          return unknown_format();  // no type info for specs parsing
+        }
+      }
     }
   } else if constexpr (str[POS] == '}') {
-    if (POS + 1 == str.size())
-      throw format_error("unmatched '}' in format string");
-    return parse_tail<Args, POS + 2, ID>(make_text(str, POS, 1), format_str);
+    if constexpr (POS + 1 == str.size())
+      FMT_THROW(format_error("unmatched '}' in format string"));
+    return parse_tail<Args, POS + 2, ID>(make_text(str, POS, 1), fmt);
   } else {
     constexpr auto end = parse_text(str, POS + 1);
-    return parse_tail<Args, end, ID>(make_text(str, POS, end - POS),
-                                     format_str);
-  }
-}
-#endif  // __cpp_if_constexpr
-}  // namespace internal
-
-#if FMT_USE_CONSTEXPR
-#  ifdef __cpp_if_constexpr
-template <typename... Args, typename S,
-          FMT_ENABLE_IF(is_compile_string<S>::value)>
-constexpr auto compile(S format_str) {
-  constexpr basic_string_view<typename S::char_type> str = format_str;
-  if constexpr (str.size() == 0) {
-    return internal::make_text(str, 0, 0);
-  } else {
-    constexpr auto result =
-        internal::compile_format_string<internal::type_list<Args...>, 0, 0>(
-            format_str);
-    if constexpr (std::is_same<remove_cvref_t<decltype(result)>,
-                               internal::unknown_format>()) {
-      return internal::compiled_format<S, Args...>(to_string_view(format_str));
+    if constexpr (end - POS > 1) {
+      return parse_tail<Args, end, ID>(make_text(str, POS, end - POS), fmt);
     } else {
-      return result;
+      return parse_tail<Args, end, ID>(code_unit<char_type>{str[POS]}, fmt);
     }
   }
 }
 
+template <typename... Args, typename S,
+          FMT_ENABLE_IF(is_compiled_string<S>::value)>
+constexpr auto compile(S fmt) {
+  constexpr auto str = basic_string_view<typename S::char_type>(fmt);
+  if constexpr (str.size() == 0) {
+    return detail::make_text(str, 0, 0);
+  } else {
+    constexpr auto result =
+        detail::compile_format_string<detail::type_list<Args...>, 0, 0>(fmt);
+    return result;
+  }
+}
+#endif  // defined(__cpp_if_constexpr) && defined(__cpp_return_type_deduction)
+}  // namespace detail
+
+FMT_BEGIN_EXPORT
+
+#if defined(__cpp_if_constexpr) && defined(__cpp_return_type_deduction)
+
 template <typename CompiledFormat, typename... Args,
           typename Char = typename CompiledFormat::char_type,
-          FMT_ENABLE_IF(internal::is_compiled_format<CompiledFormat>::value)>
-std::basic_string<Char> format(const CompiledFormat& cf, const Args&... args) {
-  basic_memory_buffer<Char> buffer;
-  cf.format(std::back_inserter(buffer), args...);
-  return to_string(buffer);
+          FMT_ENABLE_IF(detail::is_compiled_format<CompiledFormat>::value)>
+FMT_INLINE std::basic_string<Char> format(const CompiledFormat& cf,
+                                          const Args&... args) {
+  auto s = std::basic_string<Char>();
+  cf.format(std::back_inserter(s), args...);
+  return s;
 }
 
 template <typename OutputIt, typename CompiledFormat, typename... Args,
-          FMT_ENABLE_IF(internal::is_compiled_format<CompiledFormat>::value)>
-OutputIt format_to(OutputIt out, const CompiledFormat& cf,
-                   const Args&... args) {
+          FMT_ENABLE_IF(detail::is_compiled_format<CompiledFormat>::value)>
+constexpr FMT_INLINE OutputIt format_to(OutputIt out, const CompiledFormat& cf,
+                                        const Args&... args) {
   return cf.format(out, args...);
 }
-#  else
-template <typename... Args, typename S,
-          FMT_ENABLE_IF(is_compile_string<S>::value)>
-constexpr auto compile(S format_str) -> internal::compiled_format<S, Args...> {
-  return internal::compiled_format<S, Args...>(to_string_view(format_str));
-}
-#  endif  // __cpp_if_constexpr
-#endif    // FMT_USE_CONSTEXPR
 
-// Compiles the format string which must be a string literal.
-template <typename... Args, typename Char, size_t N>
-auto compile(const Char (&format_str)[N])
-    -> internal::compiled_format<const Char*, Args...> {
-  return internal::compiled_format<const Char*, Args...>(
-      basic_string_view<Char>(format_str, N - 1));
+template <typename S, typename... Args,
+          FMT_ENABLE_IF(is_compiled_string<S>::value)>
+FMT_INLINE std::basic_string<typename S::char_type> format(const S&,
+                                                           Args&&... args) {
+  if constexpr (std::is_same<typename S::char_type, char>::value) {
+    constexpr auto str = basic_string_view<typename S::char_type>(S());
+    if constexpr (str.size() == 2 && str[0] == '{' && str[1] == '}') {
+      const auto& first = detail::first(args...);
+      if constexpr (detail::is_named_arg<
+                        remove_cvref_t<decltype(first)>>::value) {
+        return fmt::to_string(first.value);
+      } else {
+        return fmt::to_string(first);
+      }
+    }
+  }
+  constexpr auto compiled = detail::compile<Args...>(S());
+  if constexpr (std::is_same<remove_cvref_t<decltype(compiled)>,
+                             detail::unknown_format>()) {
+    return fmt::format(
+        static_cast<basic_string_view<typename S::char_type>>(S()),
+        std::forward<Args>(args)...);
+  } else {
+    return fmt::format(compiled, std::forward<Args>(args)...);
+  }
 }
 
-template <typename CompiledFormat, typename... Args,
-          typename Char = typename CompiledFormat::char_type,
-          FMT_ENABLE_IF(std::is_base_of<internal::basic_compiled_format,
-                                        CompiledFormat>::value)>
-std::basic_string<Char> format(const CompiledFormat& cf, const Args&... args) {
-  basic_memory_buffer<Char> buffer;
-  using range = buffer_range<Char>;
-  using context = buffer_context<Char>;
-  internal::cf::vformat_to<context>(range(buffer), cf,
-                                    make_format_args<context>(args...));
-  return to_string(buffer);
+template <typename OutputIt, typename S, typename... Args,
+          FMT_ENABLE_IF(is_compiled_string<S>::value)>
+FMT_CONSTEXPR OutputIt format_to(OutputIt out, const S&, Args&&... args) {
+  constexpr auto compiled = detail::compile<Args...>(S());
+  if constexpr (std::is_same<remove_cvref_t<decltype(compiled)>,
+                             detail::unknown_format>()) {
+    return fmt::format_to(
+        out, static_cast<basic_string_view<typename S::char_type>>(S()),
+        std::forward<Args>(args)...);
+  } else {
+    return fmt::format_to(out, compiled, std::forward<Args>(args)...);
+  }
+}
+#endif
+
+template <typename OutputIt, typename S, typename... Args,
+          FMT_ENABLE_IF(is_compiled_string<S>::value)>
+auto format_to_n(OutputIt out, size_t n, const S& fmt, Args&&... args)
+    -> format_to_n_result<OutputIt> {
+  using traits = detail::fixed_buffer_traits;
+  auto buf = detail::iterator_buffer<OutputIt, char, traits>(out, n);
+  fmt::format_to(std::back_inserter(buf), fmt, std::forward<Args>(args)...);
+  return {buf.out(), buf.count()};
 }
 
-template <typename OutputIt, typename CompiledFormat, typename... Args,
-          FMT_ENABLE_IF(std::is_base_of<internal::basic_compiled_format,
-                                        CompiledFormat>::value)>
-OutputIt format_to(OutputIt out, const CompiledFormat& cf,
-                   const Args&... args) {
-  using char_type = typename CompiledFormat::char_type;
-  using range = internal::output_range<OutputIt, char_type>;
-  using context = format_context_t<OutputIt, char_type>;
-  return internal::cf::vformat_to<context>(range(out), cf,
-                                           make_format_args<context>(args...));
+template <typename S, typename... Args,
+          FMT_ENABLE_IF(is_compiled_string<S>::value)>
+FMT_CONSTEXPR20 auto formatted_size(const S& fmt, const Args&... args)
+    -> size_t {
+  auto buf = detail::counting_buffer<>();
+  fmt::format_to(appender(buf), fmt, args...);
+  return buf.count();
 }
 
-template <typename OutputIt, typename CompiledFormat, typename... Args,
-          FMT_ENABLE_IF(internal::is_output_iterator<OutputIt>::value)>
-format_to_n_result<OutputIt> format_to_n(OutputIt out, size_t n,
-                                         const CompiledFormat& cf,
-                                         const Args&... args) {
-  auto it =
-      format_to(internal::truncating_iterator<OutputIt>(out, n), cf, args...);
-  return {it.base(), it.count()};
+template <typename S, typename... Args,
+          FMT_ENABLE_IF(is_compiled_string<S>::value)>
+void print(std::FILE* f, const S& fmt, const Args&... args) {
+  auto buf = memory_buffer();
+  fmt::format_to(appender(buf), fmt, args...);
+  detail::print(f, {buf.data(), buf.size()});
 }
 
-template <typename CompiledFormat, typename... Args>
-std::size_t formatted_size(const CompiledFormat& cf, const Args&... args) {
-  return format_to(internal::counting_iterator(), cf, args...).count();
+template <typename S, typename... Args,
+          FMT_ENABLE_IF(is_compiled_string<S>::value)>
+void print(const S& fmt, const Args&... args) {
+  print(stdout, fmt, args...);
 }
 
+#if FMT_USE_NONTYPE_TEMPLATE_ARGS
+inline namespace literals {
+template <detail::fixed_string Str> constexpr auto operator""_cf() {
+  return FMT_COMPILE(Str.data);
+}
+}  // namespace literals
+#endif
+
+FMT_END_EXPORT
 FMT_END_NAMESPACE
 
 #endif  // FMT_COMPILE_H_

include/spdlog/fmt/bundled/fmt.license.rst

@@ -1,4 +1,4 @@
-Copyright (c) 2012 - present, Victor Zverovich
+Copyright (c) 2012 - present, Victor Zverovich and {fmt} contributors
 
 Permission is hereby granted, free of charge, to any person obtaining
 a copy of this software and associated documentation files (the

include/spdlog/fmt/bundled/locale.h

@@ -1,78 +0,0 @@
-// Formatting library for C++ - std::locale support
-//
-// Copyright (c) 2012 - present, Victor Zverovich
-// All rights reserved.
-//
-// For the license information refer to format.h.
-
-#ifndef FMT_LOCALE_H_
-#define FMT_LOCALE_H_
-
-#include <locale>
-
-#include "format.h"
-
-FMT_BEGIN_NAMESPACE
-
-namespace internal {
-template <typename Char>
-typename buffer_context<Char>::iterator vformat_to(
-    const std::locale& loc, buffer<Char>& buf,
-    basic_string_view<Char> format_str,
-    basic_format_args<buffer_context<type_identity_t<Char>>> args) {
-  using range = buffer_range<Char>;
-  return vformat_to<arg_formatter<range>>(buf, to_string_view(format_str), args,
-                                          internal::locale_ref(loc));
-}
-
-template <typename Char>
-std::basic_string<Char> vformat(
-    const std::locale& loc, basic_string_view<Char> format_str,
-    basic_format_args<buffer_context<type_identity_t<Char>>> args) {
-  basic_memory_buffer<Char> buffer;
-  internal::vformat_to(loc, buffer, format_str, args);
-  return fmt::to_string(buffer);
-}
-}  // namespace internal
-
-template <typename S, typename Char = char_t<S>>
-inline std::basic_string<Char> vformat(
-    const std::locale& loc, const S& format_str,
-    basic_format_args<buffer_context<type_identity_t<Char>>> args) {
-  return internal::vformat(loc, to_string_view(format_str), args);
-}
-
-template <typename S, typename... Args, typename Char = char_t<S>>
-inline std::basic_string<Char> format(const std::locale& loc,
-                                      const S& format_str, Args&&... args) {
-  return internal::vformat(
-      loc, to_string_view(format_str),
-      internal::make_args_checked<Args...>(format_str, args...));
-}
-
-template <typename S, typename OutputIt, typename... Args,
-          typename Char = enable_if_t<
-              internal::is_output_iterator<OutputIt>::value, char_t<S>>>
-inline OutputIt vformat_to(
-    OutputIt out, const std::locale& loc, const S& format_str,
-    format_args_t<type_identity_t<OutputIt>, Char> args) {
-  using range = internal::output_range<OutputIt, Char>;
-  return vformat_to<arg_formatter<range>>(
-      range(out), to_string_view(format_str), args, internal::locale_ref(loc));
-}
-
-template <typename OutputIt, typename S, typename... Args,
-          FMT_ENABLE_IF(internal::is_output_iterator<OutputIt>::value&&
-                            internal::is_string<S>::value)>
-inline OutputIt format_to(OutputIt out, const std::locale& loc,
-                          const S& format_str, Args&&... args) {
-  internal::check_format_string<Args...>(format_str);
-  using context = format_context_t<OutputIt, char_t<S>>;
-  format_arg_store<context, Args...> as{args...};
-  return vformat_to(out, loc, to_string_view(format_str),
-                    basic_format_args<context>(as));
-}
-
-FMT_END_NAMESPACE
-
-#endif  // FMT_LOCALE_H_

include/spdlog/fmt/bundled/os.h

@@ -0,0 +1,427 @@
+// Formatting library for C++ - optional OS-specific functionality
+//
+// Copyright (c) 2012 - present, Victor Zverovich
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+#ifndef FMT_OS_H_
+#define FMT_OS_H_
+
+#include "format.h"
+
+#ifndef FMT_MODULE
+#  include <cerrno>
+#  include <cstddef>
+#  include <cstdio>
+#  include <system_error>  // std::system_error
+
+#  if FMT_HAS_INCLUDE(<xlocale.h>)
+#    include <xlocale.h>  // LC_NUMERIC_MASK on macOS
+#  endif
+#endif  // FMT_MODULE
+
+#ifndef FMT_USE_FCNTL
+// UWP doesn't provide _pipe.
+#  if FMT_HAS_INCLUDE("winapifamily.h")
+#    include <winapifamily.h>
+#  endif
+#  if (FMT_HAS_INCLUDE(<fcntl.h>) || defined(__APPLE__) || \
+       defined(__linux__)) &&                              \
+      (!defined(WINAPI_FAMILY) ||                          \
+       (WINAPI_FAMILY == WINAPI_FAMILY_DESKTOP_APP))
+#    include <fcntl.h>  // for O_RDONLY
+#    define FMT_USE_FCNTL 1
+#  else
+#    define FMT_USE_FCNTL 0
+#  endif
+#endif
+
+#ifndef FMT_POSIX
+#  if defined(_WIN32) && !defined(__MINGW32__)
+// Fix warnings about deprecated symbols.
+#    define FMT_POSIX(call) _##call
+#  else
+#    define FMT_POSIX(call) call
+#  endif
+#endif
+
+// Calls to system functions are wrapped in FMT_SYSTEM for testability.
+#ifdef FMT_SYSTEM
+#  define FMT_HAS_SYSTEM
+#  define FMT_POSIX_CALL(call) FMT_SYSTEM(call)
+#else
+#  define FMT_SYSTEM(call) ::call
+#  ifdef _WIN32
+// Fix warnings about deprecated symbols.
+#    define FMT_POSIX_CALL(call) ::_##call
+#  else
+#    define FMT_POSIX_CALL(call) ::call
+#  endif
+#endif
+
+// Retries the expression while it evaluates to error_result and errno
+// equals to EINTR.
+#ifndef _WIN32
+#  define FMT_RETRY_VAL(result, expression, error_result) \
+    do {                                                  \
+      (result) = (expression);                            \
+    } while ((result) == (error_result) && errno == EINTR)
+#else
+#  define FMT_RETRY_VAL(result, expression, error_result) result = (expression)
+#endif
+
+#define FMT_RETRY(result, expression) FMT_RETRY_VAL(result, expression, -1)
+
+FMT_BEGIN_NAMESPACE
+FMT_BEGIN_EXPORT
+
+/**
+ * A reference to a null-terminated string. It can be constructed from a C
+ * string or `std::string`.
+ *
+ * You can use one of the following type aliases for common character types:
+ *
+ * +---------------+-----------------------------+
+ * | Type          | Definition                  |
+ * +===============+=============================+
+ * | cstring_view  | basic_cstring_view<char>    |
+ * +---------------+-----------------------------+
+ * | wcstring_view | basic_cstring_view<wchar_t> |
+ * +---------------+-----------------------------+
+ *
+ * This class is most useful as a parameter type for functions that wrap C APIs.
+ */
+template <typename Char> class basic_cstring_view {
+ private:
+  const Char* data_;
+
+ public:
+  /// Constructs a string reference object from a C string.
+  basic_cstring_view(const Char* s) : data_(s) {}
+
+  /// Constructs a string reference from an `std::string` object.
+  basic_cstring_view(const std::basic_string<Char>& s) : data_(s.c_str()) {}
+
+  /// Returns the pointer to a C string.
+  auto c_str() const -> const Char* { return data_; }
+};
+
+using cstring_view = basic_cstring_view<char>;
+using wcstring_view = basic_cstring_view<wchar_t>;
+
+#ifdef _WIN32
+FMT_API const std::error_category& system_category() noexcept;
+
+namespace detail {
+FMT_API void format_windows_error(buffer<char>& out, int error_code,
+                                  const char* message) noexcept;
+}
+
+FMT_API std::system_error vwindows_error(int error_code, string_view fmt,
+                                         format_args args);
+
+/**
+ * Constructs a `std::system_error` object with the description of the form
+ *
+ *     <message>: <system-message>
+ *
+ * where `<message>` is the formatted message and `<system-message>` is the
+ * system message corresponding to the error code.
+ * `error_code` is a Windows error code as given by `GetLastError`.
+ * If `error_code` is not a valid error code such as -1, the system message
+ * will look like "error -1".
+ *
+ * **Example**:
+ *
+ *     // This throws a system_error with the description
+ *     //   cannot open file 'madeup': The system cannot find the file
+ * specified.
+ *     // or similar (system message may vary).
+ *     const char *filename = "madeup";
+ *     LPOFSTRUCT of = LPOFSTRUCT();
+ *     HFILE file = OpenFile(filename, &of, OF_READ);
+ *     if (file == HFILE_ERROR) {
+ *       throw fmt::windows_error(GetLastError(),
+ *                                "cannot open file '{}'", filename);
+ *     }
+ */
+template <typename... T>
+auto windows_error(int error_code, string_view message, const T&... args)
+    -> std::system_error {
+  return vwindows_error(error_code, message, vargs<T...>{{args...}});
+}
+
+// Reports a Windows error without throwing an exception.
+// Can be used to report errors from destructors.
+FMT_API void report_windows_error(int error_code, const char* message) noexcept;
+#else
+inline auto system_category() noexcept -> const std::error_category& {
+  return std::system_category();
+}
+#endif  // _WIN32
+
+// std::system is not available on some platforms such as iOS (#2248).
+#ifdef __OSX__
+template <typename S, typename... Args, typename Char = char_t<S>>
+void say(const S& fmt, Args&&... args) {
+  std::system(format("say \"{}\"", format(fmt, args...)).c_str());
+}
+#endif
+
+// A buffered file.
+class buffered_file {
+ private:
+  FILE* file_;
+
+  friend class file;
+
+  inline explicit buffered_file(FILE* f) : file_(f) {}
+
+ public:
+  buffered_file(const buffered_file&) = delete;
+  void operator=(const buffered_file&) = delete;
+
+  // Constructs a buffered_file object which doesn't represent any file.
+  inline buffered_file() noexcept : file_(nullptr) {}
+
+  // Destroys the object closing the file it represents if any.
+  FMT_API ~buffered_file() noexcept;
+
+ public:
+  inline buffered_file(buffered_file&& other) noexcept : file_(other.file_) {
+    other.file_ = nullptr;
+  }
+
+  inline auto operator=(buffered_file&& other) -> buffered_file& {
+    close();
+    file_ = other.file_;
+    other.file_ = nullptr;
+    return *this;
+  }
+
+  // Opens a file.
+  FMT_API buffered_file(cstring_view filename, cstring_view mode);
+
+  // Closes the file.
+  FMT_API void close();
+
+  // Returns the pointer to a FILE object representing this file.
+  inline auto get() const noexcept -> FILE* { return file_; }
+
+  FMT_API auto descriptor() const -> int;
+
+  template <typename... T>
+  inline void print(string_view fmt, const T&... args) {
+    fmt::vargs<T...> vargs = {{args...}};
+    detail::is_locking<T...>() ? fmt::vprint_buffered(file_, fmt, vargs)
+                               : fmt::vprint(file_, fmt, vargs);
+  }
+};
+
+#if FMT_USE_FCNTL
+
+// A file. Closed file is represented by a file object with descriptor -1.
+// Methods that are not declared with noexcept may throw
+// fmt::system_error in case of failure. Note that some errors such as
+// closing the file multiple times will cause a crash on Windows rather
+// than an exception. You can get standard behavior by overriding the
+// invalid parameter handler with _set_invalid_parameter_handler.
+class FMT_API file {
+ private:
+  int fd_;  // File descriptor.
+
+  // Constructs a file object with a given descriptor.
+  explicit file(int fd) : fd_(fd) {}
+
+  friend struct pipe;
+
+ public:
+  // Possible values for the oflag argument to the constructor.
+  enum {
+    RDONLY = FMT_POSIX(O_RDONLY),  // Open for reading only.
+    WRONLY = FMT_POSIX(O_WRONLY),  // Open for writing only.
+    RDWR = FMT_POSIX(O_RDWR),      // Open for reading and writing.
+    CREATE = FMT_POSIX(O_CREAT),   // Create if the file doesn't exist.
+    APPEND = FMT_POSIX(O_APPEND),  // Open in append mode.
+    TRUNC = FMT_POSIX(O_TRUNC)     // Truncate the content of the file.
+  };
+
+  // Constructs a file object which doesn't represent any file.
+  inline file() noexcept : fd_(-1) {}
+
+  // Opens a file and constructs a file object representing this file.
+  file(cstring_view path, int oflag);
+
+ public:
+  file(const file&) = delete;
+  void operator=(const file&) = delete;
+
+  inline file(file&& other) noexcept : fd_(other.fd_) { other.fd_ = -1; }
+
+  // Move assignment is not noexcept because close may throw.
+  inline auto operator=(file&& other) -> file& {
+    close();
+    fd_ = other.fd_;
+    other.fd_ = -1;
+    return *this;
+  }
+
+  // Destroys the object closing the file it represents if any.
+  ~file() noexcept;
+
+  // Returns the file descriptor.
+  inline auto descriptor() const noexcept -> int { return fd_; }
+
+  // Closes the file.
+  void close();
+
+  // Returns the file size. The size has signed type for consistency with
+  // stat::st_size.
+  auto size() const -> long long;
+
+  // Attempts to read count bytes from the file into the specified buffer.
+  auto read(void* buffer, size_t count) -> size_t;
+
+  // Attempts to write count bytes from the specified buffer to the file.
+  auto write(const void* buffer, size_t count) -> size_t;
+
+  // Duplicates a file descriptor with the dup function and returns
+  // the duplicate as a file object.
+  static auto dup(int fd) -> file;
+
+  // Makes fd be the copy of this file descriptor, closing fd first if
+  // necessary.
+  void dup2(int fd);
+
+  // Makes fd be the copy of this file descriptor, closing fd first if
+  // necessary.
+  void dup2(int fd, std::error_code& ec) noexcept;
+
+  // Creates a buffered_file object associated with this file and detaches
+  // this file object from the file.
+  auto fdopen(const char* mode) -> buffered_file;
+
+#  if defined(_WIN32) && !defined(__MINGW32__)
+  // Opens a file and constructs a file object representing this file by
+  // wcstring_view filename. Windows only.
+  static file open_windows_file(wcstring_view path, int oflag);
+#  endif
+};
+
+struct FMT_API pipe {
+  file read_end;
+  file write_end;
+
+  // Creates a pipe setting up read_end and write_end file objects for reading
+  // and writing respectively.
+  pipe();
+};
+
+// Returns the memory page size.
+auto getpagesize() -> long;
+
+namespace detail {
+
+struct buffer_size {
+  constexpr buffer_size() = default;
+  size_t value = 0;
+  FMT_CONSTEXPR auto operator=(size_t val) const -> buffer_size {
+    auto bs = buffer_size();
+    bs.value = val;
+    return bs;
+  }
+};
+
+struct ostream_params {
+  int oflag = file::WRONLY | file::CREATE | file::TRUNC;
+  size_t buffer_size = BUFSIZ > 32768 ? BUFSIZ : 32768;
+
+  constexpr ostream_params() {}
+
+  template <typename... T>
+  ostream_params(T... params, int new_oflag) : ostream_params(params...) {
+    oflag = new_oflag;
+  }
+
+  template <typename... T>
+  ostream_params(T... params, detail::buffer_size bs)
+      : ostream_params(params...) {
+    this->buffer_size = bs.value;
+  }
+
+// Intel has a bug that results in failure to deduce a constructor
+// for empty parameter packs.
+#  if defined(__INTEL_COMPILER) && __INTEL_COMPILER < 2000
+  ostream_params(int new_oflag) : oflag(new_oflag) {}
+  ostream_params(detail::buffer_size bs) : buffer_size(bs.value) {}
+#  endif
+};
+
+}  // namespace detail
+
+FMT_INLINE_VARIABLE constexpr auto buffer_size = detail::buffer_size();
+
+/// A fast buffered output stream for writing from a single thread. Writing from
+/// multiple threads without external synchronization may result in a data race.
+class FMT_API ostream : private detail::buffer<char> {
+ private:
+  file file_;
+
+  ostream(cstring_view path, const detail::ostream_params& params);
+
+  static void grow(buffer<char>& buf, size_t);
+
+ public:
+  ostream(ostream&& other) noexcept;
+  ~ostream();
+
+  operator writer() {
+    detail::buffer<char>& buf = *this;
+    return buf;
+  }
+
+  inline void flush() {
+    if (size() == 0) return;
+    file_.write(data(), size() * sizeof(data()[0]));
+    clear();
+  }
+
+  template <typename... T>
+  friend auto output_file(cstring_view path, T... params) -> ostream;
+
+  inline void close() {
+    flush();
+    file_.close();
+  }
+
+  /// Formats `args` according to specifications in `fmt` and writes the
+  /// output to the file.
+  template <typename... T> void print(format_string<T...> fmt, T&&... args) {
+    vformat_to(appender(*this), fmt.str, vargs<T...>{{args...}});
+  }
+};
+
+/**
+ * Opens a file for writing. Supported parameters passed in `params`:
+ *
+ * - `<integer>`: Flags passed to [open](
+ *   https://pubs.opengroup.org/onlinepubs/007904875/functions/open.html)
+ *   (`file::WRONLY | file::CREATE | file::TRUNC` by default)
+ * - `buffer_size=<integer>`: Output buffer size
+ *
+ * **Example**:
+ *
+ *     auto out = fmt::output_file("guide.txt");
+ *     out.print("Don't {}", "Panic");
+ */
+template <typename... T>
+inline auto output_file(cstring_view path, T... params) -> ostream {
+  return {path, detail::ostream_params(params...)};
+}
+#endif  // FMT_USE_FCNTL
+
+FMT_END_EXPORT
+FMT_END_NAMESPACE
+
+#endif  // FMT_OS_H_

include/spdlog/fmt/bundled/ostream.h

@@ -8,81 +8,53 @@
 #ifndef FMT_OSTREAM_H_
 #define FMT_OSTREAM_H_
 
-#include <ostream>
+#ifndef FMT_MODULE
+#  include <fstream>  // std::filebuf
+#endif
 
-#include "format.h"
+#ifdef _WIN32
+#  ifdef __GLIBCXX__
+#    include <ext/stdio_filebuf.h>
+#    include <ext/stdio_sync_filebuf.h>
+#  endif
+#  include <io.h>
+#endif
+
+#include "chrono.h"  // formatbuf
+
+#ifdef _MSVC_STL_UPDATE
+#  define FMT_MSVC_STL_UPDATE _MSVC_STL_UPDATE
+#elif defined(_MSC_VER) && _MSC_VER < 1912  // VS 15.5
+#  define FMT_MSVC_STL_UPDATE _MSVC_LANG
+#else
+#  define FMT_MSVC_STL_UPDATE 0
+#endif
 
 FMT_BEGIN_NAMESPACE
+namespace detail {
 
-template <typename CHar> class basic_printf_parse_context;
-template <typename OutputIt, typename Char> class basic_printf_context;
-
-namespace internal {
-
-template <class Char> class formatbuf : public std::basic_streambuf<Char> {
- private:
-  using int_type = typename std::basic_streambuf<Char>::int_type;
-  using traits_type = typename std::basic_streambuf<Char>::traits_type;
-
-  buffer<Char>& buffer_;
-
- public:
-  formatbuf(buffer<Char>& buf) : buffer_(buf) {}
-
- protected:
-  // The put-area is actually always empty. This makes the implementation
-  // simpler and has the advantage that the streambuf and the buffer are always
-  // in sync and sputc never writes into uninitialized memory. The obvious
-  // disadvantage is that each call to sputc always results in a (virtual) call
-  // to overflow. There is no disadvantage here for sputn since this always
-  // results in a call to xsputn.
-
-  int_type overflow(int_type ch = traits_type::eof()) FMT_OVERRIDE {
-    if (!traits_type::eq_int_type(ch, traits_type::eof()))
-      buffer_.push_back(static_cast<Char>(ch));
-    return ch;
-  }
-
-  std::streamsize xsputn(const Char* s, std::streamsize count) FMT_OVERRIDE {
-    buffer_.append(s, s + count);
-    return count;
-  }
+// Generate a unique explicit instantion in every translation unit using a tag
+// type in an anonymous namespace.
+namespace {
+struct file_access_tag {};
+}  // namespace
+template <typename Tag, typename BufType, FILE* BufType::*FileMemberPtr>
+class file_access {
+  friend auto get_file(BufType& obj) -> FILE* { return obj.*FileMemberPtr; }
 };
 
-template <typename Char> struct test_stream : std::basic_ostream<Char> {
- private:
-  // Hide all operator<< from std::basic_ostream<Char>.
-  void_t<> operator<<(null<>);
-  void_t<> operator<<(const Char*);
-
-  template <typename T, FMT_ENABLE_IF(std::is_convertible<T, int>::value &&
-                                      !std::is_enum<T>::value)>
-  void_t<> operator<<(T);
-};
-
-// Checks if T has a user-defined operator<< (e.g. not a member of
-// std::ostream).
-template <typename T, typename Char> class is_streamable {
- private:
-  template <typename U>
-  static bool_constant<!std::is_same<decltype(std::declval<test_stream<Char>&>()
-                                              << std::declval<U>()),
-                                     void_t<>>::value>
-  test(int);
-
-  template <typename> static std::false_type test(...);
-
-  using result = decltype(test<T>(0));
-
- public:
-  static const bool value = result::value;
-};
+#if FMT_MSVC_STL_UPDATE
+template class file_access<file_access_tag, std::filebuf,
+                           &std::filebuf::_Myfile>;
+auto get_file(std::filebuf&) -> FILE*;
+#endif
 
 // Write the content of buf to os.
+// It is a separate function rather than a part of vprint to simplify testing.
 template <typename Char>
-void write(std::basic_ostream<Char>& os, buffer<Char>& buf) {
+void write_buffer(std::basic_ostream<Char>& os, buffer<Char>& buf) {
   const Char* buf_data = buf.data();
-  using unsigned_streamsize = std::make_unsigned<std::streamsize>::type;
+  using unsigned_streamsize = make_unsigned_t<std::streamsize>;
   unsigned_streamsize size = buf.size();
   unsigned_streamsize max_size = to_unsigned(max_value<std::streamsize>());
   do {
@@ -93,74 +65,103 @@ void write(std::basic_ostream<Char>& os, buffer<Char>& buf) {
   } while (size != 0);
 }
 
-template <typename Char, typename T>
-void format_value(buffer<Char>& buf, const T& value,
-                  locale_ref loc = locale_ref()) {
-  formatbuf<Char> format_buf(buf);
-  std::basic_ostream<Char> output(&format_buf);
-#if !defined(FMT_STATIC_THOUSANDS_SEPARATOR)
-  if (loc) output.imbue(loc.get<std::locale>());
-#endif
-  output.exceptions(std::ios_base::failbit | std::ios_base::badbit);
-  output << value;
-  buf.resize(buf.size());
-}
+template <typename T> struct streamed_view {
+  const T& value;
+};
+}  // namespace detail
 
 // Formats an object of type T that has an overloaded ostream operator<<.
-template <typename T, typename Char>
-struct fallback_formatter<T, Char, enable_if_t<is_streamable<T, Char>::value>>
-    : private formatter<basic_string_view<Char>, Char> {
-  auto parse(basic_format_parse_context<Char>& ctx) -> decltype(ctx.begin()) {
-    return formatter<basic_string_view<Char>, Char>::parse(ctx);
-  }
-  template <typename ParseCtx,
-            FMT_ENABLE_IF(std::is_same<
-                          ParseCtx, basic_printf_parse_context<Char>>::value)>
-  auto parse(ParseCtx& ctx) -> decltype(ctx.begin()) {
-    return ctx.begin();
-  }
+template <typename Char>
+struct basic_ostream_formatter : formatter<basic_string_view<Char>, Char> {
+  void set_debug_format() = delete;
 
-  template <typename OutputIt>
-  auto format(const T& value, basic_format_context<OutputIt, Char>& ctx)
-      -> OutputIt {
-    basic_memory_buffer<Char> buffer;
-    format_value(buffer, value, ctx.locale());
-    basic_string_view<Char> str(buffer.data(), buffer.size());
-    return formatter<basic_string_view<Char>, Char>::format(str, ctx);
-  }
-  template <typename OutputIt>
-  auto format(const T& value, basic_printf_context<OutputIt, Char>& ctx)
-      -> OutputIt {
-    basic_memory_buffer<Char> buffer;
-    format_value(buffer, value, ctx.locale());
-    return std::copy(buffer.begin(), buffer.end(), ctx.out());
+  template <typename T, typename Context>
+  auto format(const T& value, Context& ctx) const -> decltype(ctx.out()) {
+    auto buffer = basic_memory_buffer<Char>();
+    auto&& formatbuf = detail::formatbuf<std::basic_streambuf<Char>>(buffer);
+    auto&& output = std::basic_ostream<Char>(&formatbuf);
+    output.imbue(std::locale::classic());  // The default is always unlocalized.
+    output << value;
+    output.exceptions(std::ios_base::failbit | std::ios_base::badbit);
+    return formatter<basic_string_view<Char>, Char>::format(
+        {buffer.data(), buffer.size()}, ctx);
   }
 };
-}  // namespace internal
 
-template <typename Char>
-void vprint(std::basic_ostream<Char>& os, basic_string_view<Char> format_str,
-            basic_format_args<buffer_context<type_identity_t<Char>>> args) {
-  basic_memory_buffer<Char> buffer;
-  internal::vformat_to(buffer, format_str, args);
-  internal::write(os, buffer);
+using ostream_formatter = basic_ostream_formatter<char>;
+
+template <typename T, typename Char>
+struct formatter<detail::streamed_view<T>, Char>
+    : basic_ostream_formatter<Char> {
+  template <typename Context>
+  auto format(detail::streamed_view<T> view, Context& ctx) const
+      -> decltype(ctx.out()) {
+    return basic_ostream_formatter<Char>::format(view.value, ctx);
+  }
+};
+
+/**
+ * Returns a view that formats `value` via an ostream `operator<<`.
+ *
+ * **Example**:
+ *
+ *     fmt::print("Current thread id: {}\n",
+ *                fmt::streamed(std::this_thread::get_id()));
+ */
+template <typename T>
+constexpr auto streamed(const T& value) -> detail::streamed_view<T> {
+  return {value};
+}
+
+inline void vprint(std::ostream& os, string_view fmt, format_args args) {
+  auto buffer = memory_buffer();
+  detail::vformat_to(buffer, fmt, args);
+  FILE* f = nullptr;
+#if FMT_MSVC_STL_UPDATE && FMT_USE_RTTI
+  if (auto* buf = dynamic_cast<std::filebuf*>(os.rdbuf()))
+    f = detail::get_file(*buf);
+#elif defined(_WIN32) && defined(__GLIBCXX__) && FMT_USE_RTTI
+  auto* rdbuf = os.rdbuf();
+  if (auto* sfbuf = dynamic_cast<__gnu_cxx::stdio_sync_filebuf<char>*>(rdbuf))
+    f = sfbuf->file();
+  else if (auto* fbuf = dynamic_cast<__gnu_cxx::stdio_filebuf<char>*>(rdbuf))
+    f = fbuf->file();
+#endif
+#ifdef _WIN32
+  if (f) {
+    int fd = _fileno(f);
+    if (_isatty(fd)) {
+      os.flush();
+      if (detail::write_console(fd, {buffer.data(), buffer.size()})) return;
+    }
+  }
+#endif
+  detail::ignore_unused(f);
+  detail::write_buffer(os, buffer);
 }
 
 /**
-  \rst
-  Prints formatted data to the stream *os*.
-
-  **Example**::
-
-    fmt::print(cerr, "Don't {}!", "panic");
-  \endrst
+ * Prints formatted data to the stream `os`.
+ *
+ * **Example**:
+ *
+ *     fmt::print(cerr, "Don't {}!", "panic");
  */
-template <typename S, typename... Args,
-          typename Char = enable_if_t<internal::is_string<S>::value, char_t<S>>>
-void print(std::basic_ostream<Char>& os, const S& format_str, Args&&... args) {
-  vprint(os, to_string_view(format_str),
-         internal::make_args_checked<Args...>(format_str, args...));
+FMT_EXPORT template <typename... T>
+void print(std::ostream& os, format_string<T...> fmt, T&&... args) {
+  fmt::vargs<T...> vargs = {{args...}};
+  if (detail::const_check(detail::use_utf8)) return vprint(os, fmt.str, vargs);
+  auto buffer = memory_buffer();
+  detail::vformat_to(buffer, fmt.str, vargs);
+  detail::write_buffer(os, buffer);
 }
+
+FMT_EXPORT template <typename... T>
+void println(std::ostream& os, format_string<T...> fmt, T&&... args) {
+  fmt::print(os, FMT_STRING("{}\n"),
+             fmt::format(fmt, std::forward<T>(args)...));
+}
+
 FMT_END_NAMESPACE
 
 #endif  // FMT_OSTREAM_H_

include/spdlog/fmt/bundled/posix.h

@@ -1,2 +0,0 @@
-#include "os.h"
-#warning "fmt/posix.h is deprecated; use fmt/os.h instead"

include/spdlog/fmt/bundled/std.h

@@ -0,0 +1,728 @@
+// Formatting library for C++ - formatters for standard library types
+//
+// Copyright (c) 2012 - present, Victor Zverovich
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+#ifndef FMT_STD_H_
+#define FMT_STD_H_
+
+#include "format.h"
+#include "ostream.h"
+
+#ifndef FMT_MODULE
+#  include <atomic>
+#  include <bitset>
+#  include <complex>
+#  include <cstdlib>
+#  include <exception>
+#  include <functional>
+#  include <memory>
+#  include <thread>
+#  include <type_traits>
+#  include <typeinfo>
+#  include <utility>
+#  include <vector>
+
+// Check FMT_CPLUSPLUS to suppress a bogus warning in MSVC.
+#  if FMT_CPLUSPLUS >= 201703L
+#    if FMT_HAS_INCLUDE(<filesystem>) && \
+        (!defined(FMT_CPP_LIB_FILESYSTEM) || FMT_CPP_LIB_FILESYSTEM != 0)
+#      include <filesystem>
+#    endif
+#    if FMT_HAS_INCLUDE(<variant>)
+#      include <variant>
+#    endif
+#    if FMT_HAS_INCLUDE(<optional>)
+#      include <optional>
+#    endif
+#  endif
+// Use > instead of >= in the version check because <source_location> may be
+// available after C++17 but before C++20 is marked as implemented.
+#  if FMT_CPLUSPLUS > 201703L && FMT_HAS_INCLUDE(<source_location>)
+#    include <source_location>
+#  endif
+#  if FMT_CPLUSPLUS > 202002L && FMT_HAS_INCLUDE(<expected>)
+#    include <expected>
+#  endif
+#endif  // FMT_MODULE
+
+#if FMT_HAS_INCLUDE(<version>)
+#  include <version>
+#endif
+
+// GCC 4 does not support FMT_HAS_INCLUDE.
+#if FMT_HAS_INCLUDE(<cxxabi.h>) || defined(__GLIBCXX__)
+#  include <cxxabi.h>
+// Android NDK with gabi++ library on some architectures does not implement
+// abi::__cxa_demangle().
+#  ifndef __GABIXX_CXXABI_H__
+#    define FMT_HAS_ABI_CXA_DEMANGLE
+#  endif
+#endif
+
+// For older Xcode versions, __cpp_lib_xxx flags are inaccurately defined.
+#ifndef FMT_CPP_LIB_FILESYSTEM
+#  ifdef __cpp_lib_filesystem
+#    define FMT_CPP_LIB_FILESYSTEM __cpp_lib_filesystem
+#  else
+#    define FMT_CPP_LIB_FILESYSTEM 0
+#  endif
+#endif
+
+#ifndef FMT_CPP_LIB_VARIANT
+#  ifdef __cpp_lib_variant
+#    define FMT_CPP_LIB_VARIANT __cpp_lib_variant
+#  else
+#    define FMT_CPP_LIB_VARIANT 0
+#  endif
+#endif
+
+#if FMT_CPP_LIB_FILESYSTEM
+FMT_BEGIN_NAMESPACE
+
+namespace detail {
+
+template <typename Char, typename PathChar>
+auto get_path_string(const std::filesystem::path& p,
+                     const std::basic_string<PathChar>& native) {
+  if constexpr (std::is_same_v<Char, char> && std::is_same_v<PathChar, wchar_t>)
+    return to_utf8<wchar_t>(native, to_utf8_error_policy::replace);
+  else
+    return p.string<Char>();
+}
+
+template <typename Char, typename PathChar>
+void write_escaped_path(basic_memory_buffer<Char>& quoted,
+                        const std::filesystem::path& p,
+                        const std::basic_string<PathChar>& native) {
+  if constexpr (std::is_same_v<Char, char> &&
+                std::is_same_v<PathChar, wchar_t>) {
+    auto buf = basic_memory_buffer<wchar_t>();
+    write_escaped_string<wchar_t>(std::back_inserter(buf), native);
+    bool valid = to_utf8<wchar_t>::convert(quoted, {buf.data(), buf.size()});
+    FMT_ASSERT(valid, "invalid utf16");
+  } else if constexpr (std::is_same_v<Char, PathChar>) {
+    write_escaped_string<std::filesystem::path::value_type>(
+        std::back_inserter(quoted), native);
+  } else {
+    write_escaped_string<Char>(std::back_inserter(quoted), p.string<Char>());
+  }
+}
+
+}  // namespace detail
+
+template <typename Char> struct formatter<std::filesystem::path, Char> {
+ private:
+  format_specs specs_;
+  detail::arg_ref<Char> width_ref_;
+  bool debug_ = false;
+  char path_type_ = 0;
+
+ public:
+  FMT_CONSTEXPR void set_debug_format(bool set = true) { debug_ = set; }
+
+  FMT_CONSTEXPR auto parse(parse_context<Char>& ctx) {
+    auto it = ctx.begin(), end = ctx.end();
+    if (it == end) return it;
+
+    it = detail::parse_align(it, end, specs_);
+    if (it == end) return it;
+
+    Char c = *it;
+    if ((c >= '0' && c <= '9') || c == '{')
+      it = detail::parse_width(it, end, specs_, width_ref_, ctx);
+    if (it != end && *it == '?') {
+      debug_ = true;
+      ++it;
+    }
+    if (it != end && (*it == 'g')) path_type_ = detail::to_ascii(*it++);
+    return it;
+  }
+
+  template <typename FormatContext>
+  auto format(const std::filesystem::path& p, FormatContext& ctx) const {
+    auto specs = specs_;
+    auto path_string =
+        !path_type_ ? p.native()
+                    : p.generic_string<std::filesystem::path::value_type>();
+
+    detail::handle_dynamic_spec(specs.dynamic_width(), specs.width, width_ref_,
+                                ctx);
+    if (!debug_) {
+      auto s = detail::get_path_string<Char>(p, path_string);
+      return detail::write(ctx.out(), basic_string_view<Char>(s), specs);
+    }
+    auto quoted = basic_memory_buffer<Char>();
+    detail::write_escaped_path(quoted, p, path_string);
+    return detail::write(ctx.out(),
+                         basic_string_view<Char>(quoted.data(), quoted.size()),
+                         specs);
+  }
+};
+
+class path : public std::filesystem::path {
+ public:
+  auto display_string() const -> std::string {
+    const std::filesystem::path& base = *this;
+    return fmt::format(FMT_STRING("{}"), base);
+  }
+  auto system_string() const -> std::string { return string(); }
+
+  auto generic_display_string() const -> std::string {
+    const std::filesystem::path& base = *this;
+    return fmt::format(FMT_STRING("{:g}"), base);
+  }
+  auto generic_system_string() const -> std::string { return generic_string(); }
+};
+
+FMT_END_NAMESPACE
+#endif  // FMT_CPP_LIB_FILESYSTEM
+
+FMT_BEGIN_NAMESPACE
+template <std::size_t N, typename Char>
+struct formatter<std::bitset<N>, Char>
+    : nested_formatter<basic_string_view<Char>, Char> {
+ private:
+  // Functor because C++11 doesn't support generic lambdas.
+  struct writer {
+    const std::bitset<N>& bs;
+
+    template <typename OutputIt>
+    FMT_CONSTEXPR auto operator()(OutputIt out) -> OutputIt {
+      for (auto pos = N; pos > 0; --pos) {
+        out = detail::write<Char>(out, bs[pos - 1] ? Char('1') : Char('0'));
+      }
+
+      return out;
+    }
+  };
+
+ public:
+  template <typename FormatContext>
+  auto format(const std::bitset<N>& bs, FormatContext& ctx) const
+      -> decltype(ctx.out()) {
+    return this->write_padded(ctx, writer{bs});
+  }
+};
+
+template <typename Char>
+struct formatter<std::thread::id, Char> : basic_ostream_formatter<Char> {};
+FMT_END_NAMESPACE
+
+#ifdef __cpp_lib_optional
+FMT_BEGIN_NAMESPACE
+template <typename T, typename Char>
+struct formatter<std::optional<T>, Char,
+                 std::enable_if_t<is_formattable<T, Char>::value>> {
+ private:
+  formatter<T, Char> underlying_;
+  static constexpr basic_string_view<Char> optional =
+      detail::string_literal<Char, 'o', 'p', 't', 'i', 'o', 'n', 'a', 'l',
+                             '('>{};
+  static constexpr basic_string_view<Char> none =
+      detail::string_literal<Char, 'n', 'o', 'n', 'e'>{};
+
+  template <class U>
+  FMT_CONSTEXPR static auto maybe_set_debug_format(U& u, bool set)
+      -> decltype(u.set_debug_format(set)) {
+    u.set_debug_format(set);
+  }
+
+  template <class U>
+  FMT_CONSTEXPR static void maybe_set_debug_format(U&, ...) {}
+
+ public:
+  FMT_CONSTEXPR auto parse(parse_context<Char>& ctx) {
+    maybe_set_debug_format(underlying_, true);
+    return underlying_.parse(ctx);
+  }
+
+  template <typename FormatContext>
+  auto format(const std::optional<T>& opt, FormatContext& ctx) const
+      -> decltype(ctx.out()) {
+    if (!opt) return detail::write<Char>(ctx.out(), none);
+
+    auto out = ctx.out();
+    out = detail::write<Char>(out, optional);
+    ctx.advance_to(out);
+    out = underlying_.format(*opt, ctx);
+    return detail::write(out, ')');
+  }
+};
+FMT_END_NAMESPACE
+#endif  // __cpp_lib_optional
+
+#if defined(__cpp_lib_expected) || FMT_CPP_LIB_VARIANT
+
+FMT_BEGIN_NAMESPACE
+namespace detail {
+
+template <typename Char, typename OutputIt, typename T>
+auto write_escaped_alternative(OutputIt out, const T& v) -> OutputIt {
+  if constexpr (has_to_string_view<T>::value)
+    return write_escaped_string<Char>(out, detail::to_string_view(v));
+  if constexpr (std::is_same_v<T, Char>) return write_escaped_char(out, v);
+  return write<Char>(out, v);
+}
+
+}  // namespace detail
+
+FMT_END_NAMESPACE
+#endif
+
+#ifdef __cpp_lib_expected
+FMT_BEGIN_NAMESPACE
+
+template <typename T, typename E, typename Char>
+struct formatter<std::expected<T, E>, Char,
+                 std::enable_if_t<(std::is_void<T>::value ||
+                                   is_formattable<T, Char>::value) &&
+                                  is_formattable<E, Char>::value>> {
+  FMT_CONSTEXPR auto parse(parse_context<Char>& ctx) -> const Char* {
+    return ctx.begin();
+  }
+
+  template <typename FormatContext>
+  auto format(const std::expected<T, E>& value, FormatContext& ctx) const
+      -> decltype(ctx.out()) {
+    auto out = ctx.out();
+
+    if (value.has_value()) {
+      out = detail::write<Char>(out, "expected(");
+      if constexpr (!std::is_void<T>::value)
+        out = detail::write_escaped_alternative<Char>(out, *value);
+    } else {
+      out = detail::write<Char>(out, "unexpected(");
+      out = detail::write_escaped_alternative<Char>(out, value.error());
+    }
+    *out++ = ')';
+    return out;
+  }
+};
+FMT_END_NAMESPACE
+#endif  // __cpp_lib_expected
+
+#ifdef __cpp_lib_source_location
+FMT_BEGIN_NAMESPACE
+template <> struct formatter<std::source_location> {
+  FMT_CONSTEXPR auto parse(parse_context<>& ctx) { return ctx.begin(); }
+
+  template <typename FormatContext>
+  auto format(const std::source_location& loc, FormatContext& ctx) const
+      -> decltype(ctx.out()) {
+    auto out = ctx.out();
+    out = detail::write(out, loc.file_name());
+    out = detail::write(out, ':');
+    out = detail::write<char>(out, loc.line());
+    out = detail::write(out, ':');
+    out = detail::write<char>(out, loc.column());
+    out = detail::write(out, ": ");
+    out = detail::write(out, loc.function_name());
+    return out;
+  }
+};
+FMT_END_NAMESPACE
+#endif
+
+#if FMT_CPP_LIB_VARIANT
+FMT_BEGIN_NAMESPACE
+namespace detail {
+
+template <typename T>
+using variant_index_sequence =
+    std::make_index_sequence<std::variant_size<T>::value>;
+
+template <typename> struct is_variant_like_ : std::false_type {};
+template <typename... Types>
+struct is_variant_like_<std::variant<Types...>> : std::true_type {};
+
+// formattable element check.
+template <typename T, typename C> class is_variant_formattable_ {
+  template <std::size_t... Is>
+  static std::conjunction<
+      is_formattable<std::variant_alternative_t<Is, T>, C>...>
+      check(std::index_sequence<Is...>);
+
+ public:
+  static constexpr const bool value =
+      decltype(check(variant_index_sequence<T>{}))::value;
+};
+
+}  // namespace detail
+
+template <typename T> struct is_variant_like {
+  static constexpr const bool value = detail::is_variant_like_<T>::value;
+};
+
+template <typename T, typename C> struct is_variant_formattable {
+  static constexpr const bool value =
+      detail::is_variant_formattable_<T, C>::value;
+};
+
+template <typename Char> struct formatter<std::monostate, Char> {
+  FMT_CONSTEXPR auto parse(parse_context<Char>& ctx) -> const Char* {
+    return ctx.begin();
+  }
+
+  template <typename FormatContext>
+  auto format(const std::monostate&, FormatContext& ctx) const
+      -> decltype(ctx.out()) {
+    return detail::write<Char>(ctx.out(), "monostate");
+  }
+};
+
+template <typename Variant, typename Char>
+struct formatter<
+    Variant, Char,
+    std::enable_if_t<std::conjunction_v<
+        is_variant_like<Variant>, is_variant_formattable<Variant, Char>>>> {
+  FMT_CONSTEXPR auto parse(parse_context<Char>& ctx) -> const Char* {
+    return ctx.begin();
+  }
+
+  template <typename FormatContext>
+  auto format(const Variant& value, FormatContext& ctx) const
+      -> decltype(ctx.out()) {
+    auto out = ctx.out();
+
+    out = detail::write<Char>(out, "variant(");
+    FMT_TRY {
+      std::visit(
+          [&](const auto& v) {
+            out = detail::write_escaped_alternative<Char>(out, v);
+          },
+          value);
+    }
+    FMT_CATCH(const std::bad_variant_access&) {
+      detail::write<Char>(out, "valueless by exception");
+    }
+    *out++ = ')';
+    return out;
+  }
+};
+FMT_END_NAMESPACE
+#endif  // FMT_CPP_LIB_VARIANT
+
+FMT_BEGIN_NAMESPACE
+template <> struct formatter<std::error_code> {
+ private:
+  format_specs specs_;
+  detail::arg_ref<char> width_ref_;
+  bool debug_ = false;
+
+ public:
+  FMT_CONSTEXPR auto parse(parse_context<>& ctx) -> const char* {
+    auto it = ctx.begin(), end = ctx.end();
+    if (it == end) return it;
+
+    it = detail::parse_align(it, end, specs_);
+
+    char c = *it;
+    if (it != end && ((c >= '0' && c <= '9') || c == '{'))
+      it = detail::parse_width(it, end, specs_, width_ref_, ctx);
+
+    if (it != end && *it == '?') {
+      debug_ = true;
+      ++it;
+    }
+    if (it != end && *it == 's') {
+      specs_.set_type(presentation_type::string);
+      ++it;
+    }
+    return it;
+  }
+
+  template <typename FormatContext>
+  FMT_CONSTEXPR20 auto format(const std::error_code& ec,
+                              FormatContext& ctx) const -> decltype(ctx.out()) {
+    auto specs = specs_;
+    detail::handle_dynamic_spec(specs.dynamic_width(), specs.width, width_ref_,
+                                ctx);
+    auto buf = memory_buffer();
+    if (specs_.type() == presentation_type::string) {
+      buf.append(ec.message());
+    } else {
+      buf.append(string_view(ec.category().name()));
+      buf.push_back(':');
+      detail::write<char>(appender(buf), ec.value());
+    }
+    auto quoted = memory_buffer();
+    auto str = string_view(buf.data(), buf.size());
+    if (debug_) {
+      detail::write_escaped_string<char>(std::back_inserter(quoted), str);
+      str = string_view(quoted.data(), quoted.size());
+    }
+    return detail::write<char>(ctx.out(), str, specs);
+  }
+};
+
+#if FMT_USE_RTTI
+namespace detail {
+
+template <typename Char, typename OutputIt>
+auto write_demangled_name(OutputIt out, const std::type_info& ti) -> OutputIt {
+#  ifdef FMT_HAS_ABI_CXA_DEMANGLE
+  int status = 0;
+  std::size_t size = 0;
+  std::unique_ptr<char, void (*)(void*)> demangled_name_ptr(
+      abi::__cxa_demangle(ti.name(), nullptr, &size, &status), &std::free);
+
+  string_view demangled_name_view;
+  if (demangled_name_ptr) {
+    demangled_name_view = demangled_name_ptr.get();
+
+    // Normalization of stdlib inline namespace names.
+    // libc++ inline namespaces.
+    //  std::__1::*       -> std::*
+    //  std::__1::__fs::* -> std::*
+    // libstdc++ inline namespaces.
+    //  std::__cxx11::*             -> std::*
+    //  std::filesystem::__cxx11::* -> std::filesystem::*
+    if (demangled_name_view.starts_with("std::")) {
+      char* begin = demangled_name_ptr.get();
+      char* to = begin + 5;  // std::
+      for (char *from = to, *end = begin + demangled_name_view.size();
+           from < end;) {
+        // This is safe, because demangled_name is NUL-terminated.
+        if (from[0] == '_' && from[1] == '_') {
+          char* next = from + 1;
+          while (next < end && *next != ':') next++;
+          if (next[0] == ':' && next[1] == ':') {
+            from = next + 2;
+            continue;
+          }
+        }
+        *to++ = *from++;
+      }
+      demangled_name_view = {begin, detail::to_unsigned(to - begin)};
+    }
+  } else {
+    demangled_name_view = string_view(ti.name());
+  }
+  return detail::write_bytes<Char>(out, demangled_name_view);
+#  elif FMT_MSC_VERSION
+  const string_view demangled_name(ti.name());
+  for (std::size_t i = 0; i < demangled_name.size(); ++i) {
+    auto sub = demangled_name;
+    sub.remove_prefix(i);
+    if (sub.starts_with("enum ")) {
+      i += 4;
+      continue;
+    }
+    if (sub.starts_with("class ") || sub.starts_with("union ")) {
+      i += 5;
+      continue;
+    }
+    if (sub.starts_with("struct ")) {
+      i += 6;
+      continue;
+    }
+    if (*sub.begin() != ' ') *out++ = *sub.begin();
+  }
+  return out;
+#  else
+  return detail::write_bytes<Char>(out, string_view(ti.name()));
+#  endif
+}
+
+}  // namespace detail
+
+template <typename Char>
+struct formatter<std::type_info, Char  // DEPRECATED! Mixing code unit types.
+                 > {
+ public:
+  FMT_CONSTEXPR auto parse(parse_context<Char>& ctx) -> const Char* {
+    return ctx.begin();
+  }
+
+  template <typename Context>
+  auto format(const std::type_info& ti, Context& ctx) const
+      -> decltype(ctx.out()) {
+    return detail::write_demangled_name<Char>(ctx.out(), ti);
+  }
+};
+#endif
+
+template <typename T, typename Char>
+struct formatter<
+    T, Char,  // DEPRECATED! Mixing code unit types.
+    typename std::enable_if<std::is_base_of<std::exception, T>::value>::type> {
+ private:
+  bool with_typename_ = false;
+
+ public:
+  FMT_CONSTEXPR auto parse(parse_context<Char>& ctx) -> const Char* {
+    auto it = ctx.begin();
+    auto end = ctx.end();
+    if (it == end || *it == '}') return it;
+    if (*it == 't') {
+      ++it;
+      with_typename_ = FMT_USE_RTTI != 0;
+    }
+    return it;
+  }
+
+  template <typename Context>
+  auto format(const std::exception& ex, Context& ctx) const
+      -> decltype(ctx.out()) {
+    auto out = ctx.out();
+#if FMT_USE_RTTI
+    if (with_typename_) {
+      out = detail::write_demangled_name<Char>(out, typeid(ex));
+      *out++ = ':';
+      *out++ = ' ';
+    }
+#endif
+    return detail::write_bytes<Char>(out, string_view(ex.what()));
+  }
+};
+
+namespace detail {
+
+template <typename T, typename Enable = void>
+struct has_flip : std::false_type {};
+
+template <typename T>
+struct has_flip<T, void_t<decltype(std::declval<T>().flip())>>
+    : std::true_type {};
+
+template <typename T> struct is_bit_reference_like {
+  static constexpr const bool value =
+      std::is_convertible<T, bool>::value &&
+      std::is_nothrow_assignable<T, bool>::value && has_flip<T>::value;
+};
+
+#ifdef _LIBCPP_VERSION
+
+// Workaround for libc++ incompatibility with C++ standard.
+// According to the Standard, `bitset::operator[] const` returns bool.
+template <typename C>
+struct is_bit_reference_like<std::__bit_const_reference<C>> {
+  static constexpr const bool value = true;
+};
+
+#endif
+
+}  // namespace detail
+
+// We can't use std::vector<bool, Allocator>::reference and
+// std::bitset<N>::reference because the compiler can't deduce Allocator and N
+// in partial specialization.
+template <typename BitRef, typename Char>
+struct formatter<BitRef, Char,
+                 enable_if_t<detail::is_bit_reference_like<BitRef>::value>>
+    : formatter<bool, Char> {
+  template <typename FormatContext>
+  FMT_CONSTEXPR auto format(const BitRef& v, FormatContext& ctx) const
+      -> decltype(ctx.out()) {
+    return formatter<bool, Char>::format(v, ctx);
+  }
+};
+
+template <typename T, typename Deleter>
+auto ptr(const std::unique_ptr<T, Deleter>& p) -> const void* {
+  return p.get();
+}
+template <typename T> auto ptr(const std::shared_ptr<T>& p) -> const void* {
+  return p.get();
+}
+
+template <typename T, typename Char>
+struct formatter<std::atomic<T>, Char,
+                 enable_if_t<is_formattable<T, Char>::value>>
+    : formatter<T, Char> {
+  template <typename FormatContext>
+  auto format(const std::atomic<T>& v, FormatContext& ctx) const
+      -> decltype(ctx.out()) {
+    return formatter<T, Char>::format(v.load(), ctx);
+  }
+};
+
+#ifdef __cpp_lib_atomic_flag_test
+template <typename Char>
+struct formatter<std::atomic_flag, Char> : formatter<bool, Char> {
+  template <typename FormatContext>
+  auto format(const std::atomic_flag& v, FormatContext& ctx) const
+      -> decltype(ctx.out()) {
+    return formatter<bool, Char>::format(v.test(), ctx);
+  }
+};
+#endif  // __cpp_lib_atomic_flag_test
+
+template <typename T, typename Char> struct formatter<std::complex<T>, Char> {
+ private:
+  detail::dynamic_format_specs<Char> specs_;
+
+  template <typename FormatContext, typename OutputIt>
+  FMT_CONSTEXPR auto do_format(const std::complex<T>& c,
+                               detail::dynamic_format_specs<Char>& specs,
+                               FormatContext& ctx, OutputIt out) const
+      -> OutputIt {
+    if (c.real() != 0) {
+      *out++ = Char('(');
+      out = detail::write<Char>(out, c.real(), specs, ctx.locale());
+      specs.set_sign(sign::plus);
+      out = detail::write<Char>(out, c.imag(), specs, ctx.locale());
+      if (!detail::isfinite(c.imag())) *out++ = Char(' ');
+      *out++ = Char('i');
+      *out++ = Char(')');
+      return out;
+    }
+    out = detail::write<Char>(out, c.imag(), specs, ctx.locale());
+    if (!detail::isfinite(c.imag())) *out++ = Char(' ');
+    *out++ = Char('i');
+    return out;
+  }
+
+ public:
+  FMT_CONSTEXPR auto parse(parse_context<Char>& ctx) -> const Char* {
+    if (ctx.begin() == ctx.end() || *ctx.begin() == '}') return ctx.begin();
+    return parse_format_specs(ctx.begin(), ctx.end(), specs_, ctx,
+                              detail::type_constant<T, Char>::value);
+  }
+
+  template <typename FormatContext>
+  auto format(const std::complex<T>& c, FormatContext& ctx) const
+      -> decltype(ctx.out()) {
+    auto specs = specs_;
+    if (specs.dynamic()) {
+      detail::handle_dynamic_spec(specs.dynamic_width(), specs.width,
+                                  specs.width_ref, ctx);
+      detail::handle_dynamic_spec(specs.dynamic_precision(), specs.precision,
+                                  specs.precision_ref, ctx);
+    }
+
+    if (specs.width == 0) return do_format(c, specs, ctx, ctx.out());
+    auto buf = basic_memory_buffer<Char>();
+
+    auto outer_specs = format_specs();
+    outer_specs.width = specs.width;
+    outer_specs.copy_fill_from(specs);
+    outer_specs.set_align(specs.align());
+
+    specs.width = 0;
+    specs.set_fill({});
+    specs.set_align(align::none);
+
+    do_format(c, specs, ctx, basic_appender<Char>(buf));
+    return detail::write<Char>(ctx.out(),
+                               basic_string_view<Char>(buf.data(), buf.size()),
+                               outer_specs);
+  }
+};
+
+template <typename T, typename Char>
+struct formatter<std::reference_wrapper<T>, Char,
+                 enable_if_t<is_formattable<remove_cvref_t<T>, Char>::value>>
+    : formatter<remove_cvref_t<T>, Char> {
+  template <typename FormatContext>
+  auto format(std::reference_wrapper<T> ref, FormatContext& ctx) const
+      -> decltype(ctx.out()) {
+    return formatter<remove_cvref_t<T>, Char>::format(ref.get(), ctx);
+  }
+};
+
+FMT_END_NAMESPACE
+#endif  // FMT_STD_H_

include/spdlog/fmt/bundled/xchar.h

@@ -0,0 +1,369 @@
+// Formatting library for C++ - optional wchar_t and exotic character support
+//
+// Copyright (c) 2012 - present, Victor Zverovich
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+#ifndef FMT_XCHAR_H_
+#define FMT_XCHAR_H_
+
+#include "color.h"
+#include "format.h"
+#include "ostream.h"
+#include "ranges.h"
+
+#ifndef FMT_MODULE
+#  include <cwchar>
+#  if FMT_USE_LOCALE
+#    include <locale>
+#  endif
+#endif
+
+FMT_BEGIN_NAMESPACE
+namespace detail {
+
+template <typename T>
+using is_exotic_char = bool_constant<!std::is_same<T, char>::value>;
+
+template <typename S, typename = void> struct format_string_char {};
+
+template <typename S>
+struct format_string_char<
+    S, void_t<decltype(sizeof(detail::to_string_view(std::declval<S>())))>> {
+  using type = char_t<S>;
+};
+
+template <typename S>
+struct format_string_char<
+    S, enable_if_t<std::is_base_of<detail::compile_string, S>::value>> {
+  using type = typename S::char_type;
+};
+
+template <typename S>
+using format_string_char_t = typename format_string_char<S>::type;
+
+inline auto write_loc(basic_appender<wchar_t> out, loc_value value,
+                      const format_specs& specs, locale_ref loc) -> bool {
+#if FMT_USE_LOCALE
+  auto& numpunct =
+      std::use_facet<std::numpunct<wchar_t>>(loc.get<std::locale>());
+  auto separator = std::wstring();
+  auto grouping = numpunct.grouping();
+  if (!grouping.empty()) separator = std::wstring(1, numpunct.thousands_sep());
+  return value.visit(loc_writer<wchar_t>{out, specs, separator, grouping, {}});
+#endif
+  return false;
+}
+}  // namespace detail
+
+FMT_BEGIN_EXPORT
+
+using wstring_view = basic_string_view<wchar_t>;
+using wformat_parse_context = parse_context<wchar_t>;
+using wformat_context = buffered_context<wchar_t>;
+using wformat_args = basic_format_args<wformat_context>;
+using wmemory_buffer = basic_memory_buffer<wchar_t>;
+
+template <typename Char, typename... T> struct basic_fstring {
+ private:
+  basic_string_view<Char> str_;
+
+  static constexpr int num_static_named_args =
+      detail::count_static_named_args<T...>();
+
+  using checker = detail::format_string_checker<
+      Char, static_cast<int>(sizeof...(T)), num_static_named_args,
+      num_static_named_args != detail::count_named_args<T...>()>;
+
+  using arg_pack = detail::arg_pack<T...>;
+
+ public:
+  using t = basic_fstring;
+
+  template <typename S,
+            FMT_ENABLE_IF(
+                std::is_convertible<const S&, basic_string_view<Char>>::value)>
+  FMT_CONSTEVAL FMT_ALWAYS_INLINE basic_fstring(const S& s) : str_(s) {
+    if (FMT_USE_CONSTEVAL)
+      detail::parse_format_string<Char>(s, checker(s, arg_pack()));
+  }
+  template <typename S,
+            FMT_ENABLE_IF(std::is_base_of<detail::compile_string, S>::value&&
+                              std::is_same<typename S::char_type, Char>::value)>
+  FMT_ALWAYS_INLINE basic_fstring(const S&) : str_(S()) {
+    FMT_CONSTEXPR auto sv = basic_string_view<Char>(S());
+    FMT_CONSTEXPR int ignore =
+        (parse_format_string(sv, checker(sv, arg_pack())), 0);
+    detail::ignore_unused(ignore);
+  }
+  basic_fstring(runtime_format_string<Char> fmt) : str_(fmt.str) {}
+
+  operator basic_string_view<Char>() const { return str_; }
+  auto get() const -> basic_string_view<Char> { return str_; }
+};
+
+template <typename Char, typename... T>
+using basic_format_string = basic_fstring<Char, T...>;
+
+template <typename... T>
+using wformat_string = typename basic_format_string<wchar_t, T...>::t;
+inline auto runtime(wstring_view s) -> runtime_format_string<wchar_t> {
+  return {{s}};
+}
+
+#ifdef __cpp_char8_t
+template <> struct is_char<char8_t> : bool_constant<detail::is_utf8_enabled> {};
+#endif
+
+template <typename... T>
+constexpr auto make_wformat_args(T&... args)
+    -> decltype(fmt::make_format_args<wformat_context>(args...)) {
+  return fmt::make_format_args<wformat_context>(args...);
+}
+
+#if !FMT_USE_NONTYPE_TEMPLATE_ARGS
+inline namespace literals {
+inline auto operator""_a(const wchar_t* s, size_t) -> detail::udl_arg<wchar_t> {
+  return {s};
+}
+}  // namespace literals
+#endif
+
+template <typename It, typename Sentinel>
+auto join(It begin, Sentinel end, wstring_view sep)
+    -> join_view<It, Sentinel, wchar_t> {
+  return {begin, end, sep};
+}
+
+template <typename Range, FMT_ENABLE_IF(!is_tuple_like<Range>::value)>
+auto join(Range&& range, wstring_view sep)
+    -> join_view<decltype(std::begin(range)), decltype(std::end(range)),
+                 wchar_t> {
+  return join(std::begin(range), std::end(range), sep);
+}
+
+template <typename T>
+auto join(std::initializer_list<T> list, wstring_view sep)
+    -> join_view<const T*, const T*, wchar_t> {
+  return join(std::begin(list), std::end(list), sep);
+}
+
+template <typename Tuple, FMT_ENABLE_IF(is_tuple_like<Tuple>::value)>
+auto join(const Tuple& tuple, basic_string_view<wchar_t> sep)
+    -> tuple_join_view<wchar_t, Tuple> {
+  return {tuple, sep};
+}
+
+template <typename Char, FMT_ENABLE_IF(!std::is_same<Char, char>::value)>
+auto vformat(basic_string_view<Char> fmt,
+             typename detail::vformat_args<Char>::type args)
+    -> std::basic_string<Char> {
+  auto buf = basic_memory_buffer<Char>();
+  detail::vformat_to(buf, fmt, args);
+  return {buf.data(), buf.size()};
+}
+
+template <typename... T>
+auto format(wformat_string<T...> fmt, T&&... args) -> std::wstring {
+  return vformat(fmt::wstring_view(fmt), fmt::make_wformat_args(args...));
+}
+
+template <typename OutputIt, typename... T>
+auto format_to(OutputIt out, wformat_string<T...> fmt, T&&... args)
+    -> OutputIt {
+  return vformat_to(out, fmt::wstring_view(fmt),
+                    fmt::make_wformat_args(args...));
+}
+
+// Pass char_t as a default template parameter instead of using
+// std::basic_string<char_t<S>> to reduce the symbol size.
+template <typename S, typename... T,
+          typename Char = detail::format_string_char_t<S>,
+          FMT_ENABLE_IF(!std::is_same<Char, char>::value &&
+                        !std::is_same<Char, wchar_t>::value)>
+auto format(const S& fmt, T&&... args) -> std::basic_string<Char> {
+  return vformat(detail::to_string_view(fmt),
+                 fmt::make_format_args<buffered_context<Char>>(args...));
+}
+
+template <typename Locale, typename S,
+          typename Char = detail::format_string_char_t<S>,
+          FMT_ENABLE_IF(detail::is_locale<Locale>::value&&
+                            detail::is_exotic_char<Char>::value)>
+inline auto vformat(const Locale& loc, const S& fmt,
+                    typename detail::vformat_args<Char>::type args)
+    -> std::basic_string<Char> {
+  auto buf = basic_memory_buffer<Char>();
+  detail::vformat_to(buf, detail::to_string_view(fmt), args,
+                     detail::locale_ref(loc));
+  return {buf.data(), buf.size()};
+}
+
+template <typename Locale, typename S, typename... T,
+          typename Char = detail::format_string_char_t<S>,
+          FMT_ENABLE_IF(detail::is_locale<Locale>::value&&
+                            detail::is_exotic_char<Char>::value)>
+inline auto format(const Locale& loc, const S& fmt, T&&... args)
+    -> std::basic_string<Char> {
+  return vformat(loc, detail::to_string_view(fmt),
+                 fmt::make_format_args<buffered_context<Char>>(args...));
+}
+
+template <typename OutputIt, typename S,
+          typename Char = detail::format_string_char_t<S>,
+          FMT_ENABLE_IF(detail::is_output_iterator<OutputIt, Char>::value&&
+                            detail::is_exotic_char<Char>::value)>
+auto vformat_to(OutputIt out, const S& fmt,
+                typename detail::vformat_args<Char>::type args) -> OutputIt {
+  auto&& buf = detail::get_buffer<Char>(out);
+  detail::vformat_to(buf, detail::to_string_view(fmt), args);
+  return detail::get_iterator(buf, out);
+}
+
+template <typename OutputIt, typename S, typename... T,
+          typename Char = detail::format_string_char_t<S>,
+          FMT_ENABLE_IF(detail::is_output_iterator<OutputIt, Char>::value &&
+                        !std::is_same<Char, char>::value &&
+                        !std::is_same<Char, wchar_t>::value)>
+inline auto format_to(OutputIt out, const S& fmt, T&&... args) -> OutputIt {
+  return vformat_to(out, detail::to_string_view(fmt),
+                    fmt::make_format_args<buffered_context<Char>>(args...));
+}
+
+template <typename Locale, typename S, typename OutputIt, typename... Args,
+          typename Char = detail::format_string_char_t<S>,
+          FMT_ENABLE_IF(detail::is_output_iterator<OutputIt, Char>::value&&
+                            detail::is_locale<Locale>::value&&
+                                detail::is_exotic_char<Char>::value)>
+inline auto vformat_to(OutputIt out, const Locale& loc, const S& fmt,
+                       typename detail::vformat_args<Char>::type args)
+    -> OutputIt {
+  auto&& buf = detail::get_buffer<Char>(out);
+  vformat_to(buf, detail::to_string_view(fmt), args, detail::locale_ref(loc));
+  return detail::get_iterator(buf, out);
+}
+
+template <typename Locale, typename OutputIt, typename S, typename... T,
+          typename Char = detail::format_string_char_t<S>,
+          bool enable = detail::is_output_iterator<OutputIt, Char>::value &&
+                        detail::is_locale<Locale>::value &&
+                        detail::is_exotic_char<Char>::value>
+inline auto format_to(OutputIt out, const Locale& loc, const S& fmt,
+                      T&&... args) ->
+    typename std::enable_if<enable, OutputIt>::type {
+  return vformat_to(out, loc, detail::to_string_view(fmt),
+                    fmt::make_format_args<buffered_context<Char>>(args...));
+}
+
+template <typename OutputIt, typename Char, typename... Args,
+          FMT_ENABLE_IF(detail::is_output_iterator<OutputIt, Char>::value&&
+                            detail::is_exotic_char<Char>::value)>
+inline auto vformat_to_n(OutputIt out, size_t n, basic_string_view<Char> fmt,
+                         typename detail::vformat_args<Char>::type args)
+    -> format_to_n_result<OutputIt> {
+  using traits = detail::fixed_buffer_traits;
+  auto buf = detail::iterator_buffer<OutputIt, Char, traits>(out, n);
+  detail::vformat_to(buf, fmt, args);
+  return {buf.out(), buf.count()};
+}
+
+template <typename OutputIt, typename S, typename... T,
+          typename Char = detail::format_string_char_t<S>,
+          FMT_ENABLE_IF(detail::is_output_iterator<OutputIt, Char>::value&&
+                            detail::is_exotic_char<Char>::value)>
+inline auto format_to_n(OutputIt out, size_t n, const S& fmt, T&&... args)
+    -> format_to_n_result<OutputIt> {
+  return vformat_to_n(out, n, fmt::basic_string_view<Char>(fmt),
+                      fmt::make_format_args<buffered_context<Char>>(args...));
+}
+
+template <typename S, typename... T,
+          typename Char = detail::format_string_char_t<S>,
+          FMT_ENABLE_IF(detail::is_exotic_char<Char>::value)>
+inline auto formatted_size(const S& fmt, T&&... args) -> size_t {
+  auto buf = detail::counting_buffer<Char>();
+  detail::vformat_to(buf, detail::to_string_view(fmt),
+                     fmt::make_format_args<buffered_context<Char>>(args...));
+  return buf.count();
+}
+
+inline void vprint(std::FILE* f, wstring_view fmt, wformat_args args) {
+  auto buf = wmemory_buffer();
+  detail::vformat_to(buf, fmt, args);
+  buf.push_back(L'\0');
+  if (std::fputws(buf.data(), f) == -1)
+    FMT_THROW(system_error(errno, FMT_STRING("cannot write to file")));
+}
+
+inline void vprint(wstring_view fmt, wformat_args args) {
+  vprint(stdout, fmt, args);
+}
+
+template <typename... T>
+void print(std::FILE* f, wformat_string<T...> fmt, T&&... args) {
+  return vprint(f, wstring_view(fmt), fmt::make_wformat_args(args...));
+}
+
+template <typename... T> void print(wformat_string<T...> fmt, T&&... args) {
+  return vprint(wstring_view(fmt), fmt::make_wformat_args(args...));
+}
+
+template <typename... T>
+void println(std::FILE* f, wformat_string<T...> fmt, T&&... args) {
+  return print(f, L"{}\n", fmt::format(fmt, std::forward<T>(args)...));
+}
+
+template <typename... T> void println(wformat_string<T...> fmt, T&&... args) {
+  return print(L"{}\n", fmt::format(fmt, std::forward<T>(args)...));
+}
+
+inline auto vformat(text_style ts, wstring_view fmt, wformat_args args)
+    -> std::wstring {
+  auto buf = wmemory_buffer();
+  detail::vformat_to(buf, ts, fmt, args);
+  return {buf.data(), buf.size()};
+}
+
+template <typename... T>
+inline auto format(text_style ts, wformat_string<T...> fmt, T&&... args)
+    -> std::wstring {
+  return fmt::vformat(ts, fmt, fmt::make_wformat_args(args...));
+}
+
+template <typename... T>
+FMT_DEPRECATED void print(std::FILE* f, text_style ts, wformat_string<T...> fmt,
+                          const T&... args) {
+  vprint(f, ts, fmt, fmt::make_wformat_args(args...));
+}
+
+template <typename... T>
+FMT_DEPRECATED void print(text_style ts, wformat_string<T...> fmt,
+                          const T&... args) {
+  return print(stdout, ts, fmt, args...);
+}
+
+inline void vprint(std::wostream& os, wstring_view fmt, wformat_args args) {
+  auto buffer = basic_memory_buffer<wchar_t>();
+  detail::vformat_to(buffer, fmt, args);
+  detail::write_buffer(os, buffer);
+}
+
+template <typename... T>
+void print(std::wostream& os, wformat_string<T...> fmt, T&&... args) {
+  vprint(os, fmt, fmt::make_format_args<buffered_context<wchar_t>>(args...));
+}
+
+template <typename... T>
+void println(std::wostream& os, wformat_string<T...> fmt, T&&... args) {
+  print(os, L"{}\n", fmt::format(fmt, std::forward<T>(args)...));
+}
+
+/// Converts `value` to `std::wstring` using the default format for type `T`.
+template <typename T> inline auto to_wstring(const T& value) -> std::wstring {
+  return format(FMT_STRING(L"{}"), value);
+}
+FMT_END_EXPORT
+FMT_END_NAMESPACE
+
+#endif  // FMT_XCHAR_H_

include/spdlog/fmt/chrono.h

@@ -0,0 +1,23 @@
+//
+// Copyright(c) 2016 Gabi Melman.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+//
+
+#pragma once
+//
+// include bundled or external copy of fmtlib's chrono support
+//
+#include <spdlog/tweakme.h>
+
+#if !defined(SPDLOG_USE_STD_FORMAT)
+    #if !defined(SPDLOG_FMT_EXTERNAL)
+        #ifdef SPDLOG_HEADER_ONLY
+            #ifndef FMT_HEADER_ONLY
+                #define FMT_HEADER_ONLY
+            #endif
+        #endif
+        #include <spdlog/fmt/bundled/chrono.h>
+    #else
+        #include <fmt/chrono.h>
+    #endif
+#endif

include/spdlog/fmt/compile.h

@@ -0,0 +1,23 @@
+//
+// Copyright(c) 2016 Gabi Melman.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+//
+
+#pragma once
+//
+// include bundled or external copy of fmtlib's compile-time support
+//
+#include <spdlog/tweakme.h>
+
+#if !defined(SPDLOG_USE_STD_FORMAT)
+    #if !defined(SPDLOG_FMT_EXTERNAL)
+        #ifdef SPDLOG_HEADER_ONLY
+            #ifndef FMT_HEADER_ONLY
+                #define FMT_HEADER_ONLY
+            #endif
+        #endif
+        #include <spdlog/fmt/bundled/compile.h>
+    #else
+        #include <fmt/compile.h>
+    #endif
+#endif

include/spdlog/fmt/fmt.h

@@ -9,17 +9,18 @@
 // Include a bundled header-only copy of fmtlib or an external one.
 // By default spdlog include its own copy.
 //
+#include <spdlog/tweakme.h>
 
-#if !defined(SPDLOG_FMT_EXTERNAL)
-#if !defined(SPDLOG_COMPILED_LIB) && !defined(FMT_HEADER_ONLY)
-#define FMT_HEADER_ONLY
+#if defined(SPDLOG_USE_STD_FORMAT)  // SPDLOG_USE_STD_FORMAT is defined - use std::format
+    #include <format>
+#elif !defined(SPDLOG_FMT_EXTERNAL)
+    #if !defined(SPDLOG_COMPILED_LIB) && !defined(FMT_HEADER_ONLY)
+        #define FMT_HEADER_ONLY
+    #endif
+    #ifndef FMT_USE_WINDOWS_H
+        #define FMT_USE_WINDOWS_H 0
+    #endif
+    #include <spdlog/fmt/bundled/format.h>
+#else  // SPDLOG_FMT_EXTERNAL is defined - use external fmtlib
+    #include <fmt/format.h>
 #endif
-#ifndef FMT_USE_WINDOWS_H
-#define FMT_USE_WINDOWS_H 0
-#endif
-#include <spdlog/fmt/bundled/core.h>
-#include <spdlog/fmt/bundled/format.h>
-#else // SPDLOG_FMT_EXTERNAL is defined - use external fmtlib
-#include <fmt/core.h>
-#include <fmt/format.h>
-#endif

include/spdlog/fmt/ostr.h

@@ -7,14 +7,17 @@
 //
 // include bundled or external copy of fmtlib's ostream support
 //
+#include <spdlog/tweakme.h>
 
-#if !defined(SPDLOG_FMT_EXTERNAL)
-#ifdef SPDLOG_HEADER_ONLY
-#ifndef FMT_HEADER_ONLY
-#define FMT_HEADER_ONLY
-#endif
-#endif
-#include <spdlog/fmt/bundled/ostream.h>
-#else
-#include <fmt/ostream.h>
+#if !defined(SPDLOG_USE_STD_FORMAT)
+    #if !defined(SPDLOG_FMT_EXTERNAL)
+        #ifdef SPDLOG_HEADER_ONLY
+            #ifndef FMT_HEADER_ONLY
+                #define FMT_HEADER_ONLY
+            #endif
+        #endif
+        #include <spdlog/fmt/bundled/ostream.h>
+    #else
+        #include <fmt/ostream.h>
+    #endif
 #endif

include/spdlog/fmt/ranges.h

@@ -0,0 +1,23 @@
+//
+// Copyright(c) 2016 Gabi Melman.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+//
+
+#pragma once
+//
+// include bundled or external copy of fmtlib's ranges support
+//
+#include <spdlog/tweakme.h>
+
+#if !defined(SPDLOG_USE_STD_FORMAT)
+    #if !defined(SPDLOG_FMT_EXTERNAL)
+        #ifdef SPDLOG_HEADER_ONLY
+            #ifndef FMT_HEADER_ONLY
+                #define FMT_HEADER_ONLY
+            #endif
+        #endif
+        #include <spdlog/fmt/bundled/ranges.h>
+    #else
+        #include <fmt/ranges.h>
+    #endif
+#endif

include/spdlog/fmt/std.h

@@ -0,0 +1,24 @@
+//
+// Copyright(c) 2016 Gabi Melman.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+//
+
+#pragma once
+//
+// include bundled or external copy of fmtlib's std support (for formatting e.g.
+// std::filesystem::path, std::thread::id, std::monostate, std::variant, ...)
+//
+#include <spdlog/tweakme.h>
+
+#if !defined(SPDLOG_USE_STD_FORMAT)
+    #if !defined(SPDLOG_FMT_EXTERNAL)
+        #ifdef SPDLOG_HEADER_ONLY
+            #ifndef FMT_HEADER_ONLY
+                #define FMT_HEADER_ONLY
+            #endif
+        #endif
+        #include <spdlog/fmt/bundled/std.h>
+    #else
+        #include <fmt/std.h>
+    #endif
+#endif

include/spdlog/fmt/xchar.h

@@ -0,0 +1,23 @@
+//
+// Copyright(c) 2016 Gabi Melman.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+//
+
+#pragma once
+//
+// include bundled or external copy of fmtlib's xchar support
+//
+#include <spdlog/tweakme.h>
+
+#if !defined(SPDLOG_USE_STD_FORMAT)
+    #if !defined(SPDLOG_FMT_EXTERNAL)
+        #ifdef SPDLOG_HEADER_ONLY
+            #ifndef FMT_HEADER_ONLY
+                #define FMT_HEADER_ONLY
+            #endif
+        #endif
+        #include <spdlog/fmt/bundled/xchar.h>
+    #else
+        #include <fmt/xchar.h>
+    #endif
+#endif

include/spdlog/formatter.h

@@ -3,16 +3,15 @@
 
 #pragma once
 
-#include <spdlog/fmt/fmt.h>
 #include <spdlog/details/log_msg.h>
+#include <spdlog/fmt/fmt.h>
 
 namespace spdlog {
 
-class formatter
-{
+class formatter {
 public:
     virtual ~formatter() = default;
     virtual void format(const details::log_msg &msg, memory_buf_t &dest) = 0;
     virtual std::unique_ptr<formatter> clone() const = 0;
 };
-} // namespace spdlog
+}  // namespace spdlog

include/spdlog/fwd.h

@@ -11,4 +11,8 @@ namespace sinks {
 class sink;
 }
 
-} // namespace spdlog
+namespace level {
+enum level_enum : int;
+}
+
+}  // namespace spdlog

include/spdlog/logger-inl.h

@@ -4,12 +4,12 @@
 #pragma once
 
 #ifndef SPDLOG_HEADER_ONLY
-#include <spdlog/logger.h>
+    #include <spdlog/logger.h>
 #endif
 
-#include <spdlog/sinks/sink.h>
 #include <spdlog/details/backtracer.h>
 #include <spdlog/pattern_formatter.h>
+#include <spdlog/sinks/sink.h>
 
 #include <cstdio>
 
@@ -17,31 +17,29 @@ namespace spdlog {
 
 // public methods
 SPDLOG_INLINE logger::logger(const logger &other)
-    : name_(other.name_)
-    , sinks_(other.sinks_)
-    , level_(other.level_.load(std::memory_order_relaxed))
-    , flush_level_(other.flush_level_.load(std::memory_order_relaxed))
-    , custom_err_handler_(other.custom_err_handler_)
-    , tracer_(other.tracer_)
-{}
+    : name_(other.name_),
+      sinks_(other.sinks_),
+      level_(other.level_.load(std::memory_order_relaxed)),
+      flush_level_(other.flush_level_.load(std::memory_order_relaxed)),
+      custom_err_handler_(other.custom_err_handler_),
+      tracer_(other.tracer_) {}
 
-SPDLOG_INLINE logger::logger(logger &&other) SPDLOG_NOEXCEPT : name_(std::move(other.name_)),
-                                                               sinks_(std::move(other.sinks_)),
-                                                               level_(other.level_.load(std::memory_order_relaxed)),
-                                                               flush_level_(other.flush_level_.load(std::memory_order_relaxed)),
-                                                               custom_err_handler_(std::move(other.custom_err_handler_)),
-                                                               tracer_(std::move(other.tracer_))
+SPDLOG_INLINE logger::logger(logger &&other) SPDLOG_NOEXCEPT
+    : name_(std::move(other.name_)),
+      sinks_(std::move(other.sinks_)),
+      level_(other.level_.load(std::memory_order_relaxed)),
+      flush_level_(other.flush_level_.load(std::memory_order_relaxed)),
+      custom_err_handler_(std::move(other.custom_err_handler_)),
+      tracer_(std::move(other.tracer_))
 
 {}
 
-SPDLOG_INLINE logger &logger::operator=(logger other) SPDLOG_NOEXCEPT
-{
+SPDLOG_INLINE logger &logger::operator=(logger other) SPDLOG_NOEXCEPT {
     this->swap(other);
     return *this;
 }
 
-SPDLOG_INLINE void logger::swap(spdlog::logger &other) SPDLOG_NOEXCEPT
-{
+SPDLOG_INLINE void logger::swap(spdlog::logger &other) SPDLOG_NOEXCEPT {
     name_.swap(other.name_);
     sinks_.swap(other.sinks_);
 
@@ -59,179 +57,121 @@ SPDLOG_INLINE void logger::swap(spdlog::logger &other) SPDLOG_NOEXCEPT
     std::swap(tracer_, other.tracer_);
 }
 
-SPDLOG_INLINE void swap(logger &a, logger &b)
-{
-    a.swap(b);
-}
+SPDLOG_INLINE void swap(logger &a, logger &b) noexcept { a.swap(b); }
 
-SPDLOG_INLINE void logger::set_level(level::level_enum log_level)
-{
-    level_.store(log_level);
-}
+SPDLOG_INLINE void logger::set_level(level::level_enum log_level) { level_.store(log_level); }
 
-SPDLOG_INLINE level::level_enum logger::level() const
-{
+SPDLOG_INLINE level::level_enum logger::level() const {
     return static_cast<level::level_enum>(level_.load(std::memory_order_relaxed));
 }
 
-SPDLOG_INLINE const std::string &logger::name() const
-{
-    return name_;
-}
+SPDLOG_INLINE const std::string &logger::name() const { return name_; }
 
 // set formatting for the sinks in this logger.
 // each sink will get a separate instance of the formatter object.
-SPDLOG_INLINE void logger::set_formatter(std::unique_ptr<formatter> f)
-{
-    for (auto it = sinks_.begin(); it != sinks_.end(); ++it)
-    {
-        if (std::next(it) == sinks_.end())
-        {
+SPDLOG_INLINE void logger::set_formatter(std::unique_ptr<formatter> f) {
+    for (auto it = sinks_.begin(); it != sinks_.end(); ++it) {
+        if (std::next(it) == sinks_.end()) {
             // last element - we can be move it.
             (*it)->set_formatter(std::move(f));
-            break; // to prevent clang-tidy warning
-        }
-        else
-        {
+            break;  // to prevent clang-tidy warning
+        } else {
             (*it)->set_formatter(f->clone());
         }
     }
 }
 
-SPDLOG_INLINE void logger::set_pattern(std::string pattern, pattern_time_type time_type)
-{
+SPDLOG_INLINE void logger::set_pattern(std::string pattern, pattern_time_type time_type) {
     auto new_formatter = details::make_unique<pattern_formatter>(std::move(pattern), time_type);
     set_formatter(std::move(new_formatter));
 }
 
 // create new backtrace sink and move to it all our child sinks
-SPDLOG_INLINE void logger::enable_backtrace(size_t n_messages)
-{
-    tracer_.enable(n_messages);
-}
+SPDLOG_INLINE void logger::enable_backtrace(size_t n_messages) { tracer_.enable(n_messages); }
 
 // restore orig sinks and level and delete the backtrace sink
-SPDLOG_INLINE void logger::disable_backtrace()
-{
-    tracer_.disable();
-}
+SPDLOG_INLINE void logger::disable_backtrace() { tracer_.disable(); }
 
-SPDLOG_INLINE void logger::dump_backtrace()
-{
-    dump_backtrace_();
-}
+SPDLOG_INLINE void logger::dump_backtrace() { dump_backtrace_(); }
 
 // flush functions
-SPDLOG_INLINE void logger::flush()
-{
-    flush_();
-}
+SPDLOG_INLINE void logger::flush() { flush_(); }
 
-SPDLOG_INLINE void logger::flush_on(level::level_enum log_level)
-{
-    flush_level_.store(log_level);
-}
+SPDLOG_INLINE void logger::flush_on(level::level_enum log_level) { flush_level_.store(log_level); }
 
-SPDLOG_INLINE level::level_enum logger::flush_level() const
-{
+SPDLOG_INLINE level::level_enum logger::flush_level() const {
     return static_cast<level::level_enum>(flush_level_.load(std::memory_order_relaxed));
 }
 
 // sinks
-SPDLOG_INLINE const std::vector<sink_ptr> &logger::sinks() const
-{
-    return sinks_;
-}
+SPDLOG_INLINE const std::vector<sink_ptr> &logger::sinks() const { return sinks_; }
 
-SPDLOG_INLINE std::vector<sink_ptr> &logger::sinks()
-{
-    return sinks_;
-}
+SPDLOG_INLINE std::vector<sink_ptr> &logger::sinks() { return sinks_; }
 
 // error handler
-SPDLOG_INLINE void logger::set_error_handler(err_handler handler)
-{
+SPDLOG_INLINE void logger::set_error_handler(err_handler handler) {
     custom_err_handler_ = std::move(handler);
 }
 
 // create new logger with same sinks and configuration.
-SPDLOG_INLINE std::shared_ptr<logger> logger::clone(std::string logger_name)
-{
+SPDLOG_INLINE std::shared_ptr<logger> logger::clone(std::string logger_name) {
     auto cloned = std::make_shared<logger>(*this);
     cloned->name_ = std::move(logger_name);
     return cloned;
 }
 
 // protected methods
-SPDLOG_INLINE void logger::log_it_(const spdlog::details::log_msg &log_msg, bool log_enabled, bool traceback_enabled)
-{
-    if (log_enabled)
-    {
+SPDLOG_INLINE void logger::log_it_(const spdlog::details::log_msg &log_msg,
+                                   bool log_enabled,
+                                   bool traceback_enabled) {
+    if (log_enabled) {
         sink_it_(log_msg);
     }
-    if (traceback_enabled)
-    {
+    if (traceback_enabled) {
         tracer_.push_back(log_msg);
     }
 }
 
-SPDLOG_INLINE void logger::sink_it_(const details::log_msg &msg)
-{
-    for (auto &sink : sinks_)
-    {
-        if (sink->should_log(msg.level))
-        {
-            SPDLOG_TRY
-            {
-                sink->log(msg);
-            }
-            SPDLOG_LOGGER_CATCH()
+SPDLOG_INLINE void logger::sink_it_(const details::log_msg &msg) {
+    for (auto &sink : sinks_) {
+        if (sink->should_log(msg.level)) {
+            SPDLOG_TRY { sink->log(msg); }
+            SPDLOG_LOGGER_CATCH(msg.source)
         }
     }
 
-    if (should_flush_(msg))
-    {
+    if (should_flush_(msg)) {
         flush_();
     }
 }
 
-SPDLOG_INLINE void logger::flush_()
-{
-    for (auto &sink : sinks_)
-    {
-        SPDLOG_TRY
-        {
-            sink->flush();
-        }
-        SPDLOG_LOGGER_CATCH()
+SPDLOG_INLINE void logger::flush_() {
+    for (auto &sink : sinks_) {
+        SPDLOG_TRY { sink->flush(); }
+        SPDLOG_LOGGER_CATCH(source_loc())
     }
 }
 
-SPDLOG_INLINE void logger::dump_backtrace_()
-{
+SPDLOG_INLINE void logger::dump_backtrace_() {
     using details::log_msg;
-    if (tracer_.enabled())
-    {
-        sink_it_(log_msg{name(), level::info, "****************** Backtrace Start ******************"});
+    if (tracer_.enabled() && !tracer_.empty()) {
+        sink_it_(
+            log_msg{name(), level::info, "****************** Backtrace Start ******************"});
         tracer_.foreach_pop([this](const log_msg &msg) { this->sink_it_(msg); });
-        sink_it_(log_msg{name(), level::info, "****************** Backtrace End ********************"});
+        sink_it_(
+            log_msg{name(), level::info, "****************** Backtrace End ********************"});
     }
 }
 
-SPDLOG_INLINE bool logger::should_flush_(const details::log_msg &msg)
-{
+SPDLOG_INLINE bool logger::should_flush_(const details::log_msg &msg) const {
     auto flush_level = flush_level_.load(std::memory_order_relaxed);
     return (msg.level >= flush_level) && (msg.level != level::off);
 }
 
-SPDLOG_INLINE void logger::err_handler_(const std::string &msg)
-{
-    if (custom_err_handler_)
-    {
+SPDLOG_INLINE void logger::err_handler_(const std::string &msg) const {
+    if (custom_err_handler_) {
         custom_err_handler_(msg);
-    }
-    else
-    {
+    } else {
         using std::chrono::system_clock;
         static std::mutex mutex;
         static std::chrono::system_clock::time_point last_report_time;
@@ -239,15 +179,20 @@ SPDLOG_INLINE void logger::err_handler_(const std::string &msg)
         std::lock_guard<std::mutex> lk{mutex};
         auto now = system_clock::now();
         err_counter++;
-        if (now - last_report_time < std::chrono::seconds(1))
-        {
+        if (now - last_report_time < std::chrono::seconds(1)) {
             return;
         }
         last_report_time = now;
         auto tm_time = details::os::localtime(system_clock::to_time_t(now));
         char date_buf[64];
         std::strftime(date_buf, sizeof(date_buf), "%Y-%m-%d %H:%M:%S", &tm_time);
-        fprintf(stderr, "[*** LOG ERROR #%04zu ***] [%s] [%s] {%s}\n", err_counter, date_buf, name().c_str(), msg.c_str());
+#if defined(USING_R) && defined(R_R_H)  // if in R environment
+        REprintf("[*** LOG ERROR #%04zu ***] [%s] [%s] %s\n", err_counter, date_buf, name().c_str(),
+                 msg.c_str());
+#else
+        std::fprintf(stderr, "[*** LOG ERROR #%04zu ***] [%s] [%s] %s\n", err_counter, date_buf,
+                     name().c_str(), msg.c_str());
+#endif
     }
 }
-} // namespace spdlog
+}  // namespace spdlog

include/spdlog/logger.h

@@ -15,144 +15,96 @@
 // formatted data, and support for different format per sink.
 
 #include <spdlog/common.h>
-#include <spdlog/details/log_msg.h>
 #include <spdlog/details/backtracer.h>
+#include <spdlog/details/log_msg.h>
 
 #ifdef SPDLOG_WCHAR_TO_UTF8_SUPPORT
-#include <spdlog/details/os.h>
+    #ifndef _WIN32
+        #error SPDLOG_WCHAR_TO_UTF8_SUPPORT only supported on windows
+    #endif
+    #include <spdlog/details/os.h>
 #endif
 
 #include <vector>
+
 #ifndef SPDLOG_NO_EXCEPTIONS
-#define SPDLOG_LOGGER_CATCH()                                                                                                              \
-    catch (const std::exception &ex)                                                                                                       \
-    {                                                                                                                                      \
-        err_handler_(ex.what());                                                                                                           \
-    }                                                                                                                                      \
-    catch (...)                                                                                                                            \
-    {                                                                                                                                      \
-        err_handler_("Unknown exception in logger");                                                                                       \
-    }
+    #define SPDLOG_LOGGER_CATCH(location)                                                 \
+        catch (const std::exception &ex) {                                                \
+            if (location.filename) {                                                      \
+                err_handler_(fmt_lib::format(SPDLOG_FMT_STRING("{} [{}({})]"), ex.what(), \
+                                             location.filename, location.line));          \
+            } else {                                                                      \
+                err_handler_(ex.what());                                                  \
+            }                                                                             \
+        }                                                                                 \
+        catch (...) {                                                                     \
+            err_handler_("Rethrowing unknown exception in logger");                       \
+            throw;                                                                        \
+        }
 #else
-#define SPDLOG_LOGGER_CATCH()
+    #define SPDLOG_LOGGER_CATCH(location)
 #endif
 
 namespace spdlog {
 
-class SPDLOG_API logger
-{
+class SPDLOG_API logger {
 public:
     // Empty logger
     explicit logger(std::string name)
-        : name_(std::move(name))
-        , sinks_()
-    {}
+        : name_(std::move(name)),
+          sinks_() {}
 
     // Logger with range on sinks
-    template<typename It>
+    template <typename It>
     logger(std::string name, It begin, It end)
-        : name_(std::move(name))
-        , sinks_(begin, end)
-    {}
+        : name_(std::move(name)),
+          sinks_(begin, end) {}
 
     // Logger with single sink
     logger(std::string name, sink_ptr single_sink)
-        : logger(std::move(name), {std::move(single_sink)})
-    {}
+        : logger(std::move(name), {std::move(single_sink)}) {}
 
     // Logger with sinks init list
     logger(std::string name, sinks_init_list sinks)
-        : logger(std::move(name), sinks.begin(), sinks.end())
-    {}
+        : logger(std::move(name), sinks.begin(), sinks.end()) {}
 
     virtual ~logger() = default;
 
     logger(const logger &other);
     logger(logger &&other) SPDLOG_NOEXCEPT;
     logger &operator=(logger other) SPDLOG_NOEXCEPT;
-
     void swap(spdlog::logger &other) SPDLOG_NOEXCEPT;
 
-    template<typename... Args>
-    void log(source_loc loc, level::level_enum lvl, string_view_t fmt, const Args &... args)
-    {
-        bool log_enabled = should_log(lvl);
-        bool traceback_enabled = tracer_.enabled();
-        if (!log_enabled && !traceback_enabled)
-        {
-            return;
-        }
-        SPDLOG_TRY
-        {
-            memory_buf_t buf;
-            fmt::format_to(buf, fmt, args...);
-            details::log_msg log_msg(loc, name_, lvl, string_view_t(buf.data(), buf.size()));
-            log_it_(log_msg, log_enabled, traceback_enabled);
-        }
-        SPDLOG_LOGGER_CATCH()
+    template <typename... Args>
+    void log(source_loc loc, level::level_enum lvl, format_string_t<Args...> fmt, Args &&...args) {
+        log_(loc, lvl, details::to_string_view(fmt), std::forward<Args>(args)...);
     }
 
-    template<typename... Args>
-    void log(level::level_enum lvl, string_view_t fmt, const Args &... args)
-    {
-        log(source_loc{}, lvl, fmt, args...);
+    template <typename... Args>
+    void log(level::level_enum lvl, format_string_t<Args...> fmt, Args &&...args) {
+        log(source_loc{}, lvl, fmt, std::forward<Args>(args)...);
     }
 
-    template<typename... Args>
-    void trace(string_view_t fmt, const Args &... args)
-    {
-        log(level::trace, fmt, args...);
-    }
-
-    template<typename... Args>
-    void debug(string_view_t fmt, const Args &... args)
-    {
-        log(level::debug, fmt, args...);
-    }
-
-    template<typename... Args>
-    void info(string_view_t fmt, const Args &... args)
-    {
-        log(level::info, fmt, args...);
-    }
-
-    template<typename... Args>
-    void warn(string_view_t fmt, const Args &... args)
-    {
-        log(level::warn, fmt, args...);
-    }
-
-    template<typename... Args>
-    void error(string_view_t fmt, const Args &... args)
-    {
-        log(level::err, fmt, args...);
-    }
-
-    template<typename... Args>
-    void critical(string_view_t fmt, const Args &... args)
-    {
-        log(level::critical, fmt, args...);
-    }
-
-    template<typename T>
-    void log(level::level_enum lvl, const T &msg)
-    {
+    template <typename T>
+    void log(level::level_enum lvl, const T &msg) {
         log(source_loc{}, lvl, msg);
     }
 
-    // T can be statically converted to string_view
-    template<class T, typename std::enable_if<std::is_convertible<const T &, spdlog::string_view_t>::value, T>::type * = nullptr>
-    void log(source_loc loc, level::level_enum lvl, const T &msg)
-    {
-        log(loc, lvl, string_view_t{msg});
+    // T cannot be statically converted to format string (including string_view/wstring_view)
+    template <class T,
+              typename std::enable_if<!is_convertible_to_any_format_string<const T &>::value,
+                                      int>::type = 0>
+    void log(source_loc loc, level::level_enum lvl, const T &msg) {
+        log(loc, lvl, "{}", msg);
     }
 
-    void log(log_clock::time_point log_time, source_loc loc, level::level_enum lvl, string_view_t msg)
-    {
+    void log(log_clock::time_point log_time,
+             source_loc loc,
+             level::level_enum lvl,
+             string_view_t msg) {
         bool log_enabled = should_log(lvl);
         bool traceback_enabled = tracer_.enabled();
-        if (!log_enabled && !traceback_enabled)
-        {
+        if (!log_enabled && !traceback_enabled) {
             return;
         }
 
@@ -160,12 +112,10 @@ public:
         log_it_(log_msg, log_enabled, traceback_enabled);
     }
 
-    void log(source_loc loc, level::level_enum lvl, string_view_t msg)
-    {
+    void log(source_loc loc, level::level_enum lvl, string_view_t msg) {
         bool log_enabled = should_log(lvl);
         bool traceback_enabled = tracer_.enabled();
-        if (!log_enabled && !traceback_enabled)
-        {
+        if (!log_enabled && !traceback_enabled) {
             return;
         }
 
@@ -173,160 +123,148 @@ public:
         log_it_(log_msg, log_enabled, traceback_enabled);
     }
 
-    void log(level::level_enum lvl, string_view_t msg)
-    {
-        log(source_loc{}, lvl, msg);
+    void log(level::level_enum lvl, string_view_t msg) { log(source_loc{}, lvl, msg); }
+
+    template <typename... Args>
+    void trace(format_string_t<Args...> fmt, Args &&...args) {
+        log(level::trace, fmt, std::forward<Args>(args)...);
     }
 
-    // T cannot be statically converted to string_view or wstring_view
-    template<class T, typename std::enable_if<!std::is_convertible<const T &, spdlog::string_view_t>::value &&
-                                                  !is_convertible_to_wstring_view<const T &>::value,
-                          T>::type * = nullptr>
-    void log(source_loc loc, level::level_enum lvl, const T &msg)
-    {
-        log(loc, lvl, "{}", msg);
+    template <typename... Args>
+    void debug(format_string_t<Args...> fmt, Args &&...args) {
+        log(level::debug, fmt, std::forward<Args>(args)...);
     }
 
-    template<typename T>
-    void trace(const T &msg)
-    {
-        log(level::trace, msg);
+    template <typename... Args>
+    void info(format_string_t<Args...> fmt, Args &&...args) {
+        log(level::info, fmt, std::forward<Args>(args)...);
     }
 
-    template<typename T>
-    void debug(const T &msg)
-    {
-        log(level::debug, msg);
+    template <typename... Args>
+    void warn(format_string_t<Args...> fmt, Args &&...args) {
+        log(level::warn, fmt, std::forward<Args>(args)...);
     }
 
-    template<typename T>
-    void info(const T &msg)
-    {
-        log(level::info, msg);
+    template <typename... Args>
+    void error(format_string_t<Args...> fmt, Args &&...args) {
+        log(level::err, fmt, std::forward<Args>(args)...);
     }
 
-    template<typename T>
-    void warn(const T &msg)
-    {
-        log(level::warn, msg);
-    }
-
-    template<typename T>
-    void error(const T &msg)
-    {
-        log(level::err, msg);
-    }
-
-    template<typename T>
-    void critical(const T &msg)
-    {
-        log(level::critical, msg);
+    template <typename... Args>
+    void critical(format_string_t<Args...> fmt, Args &&...args) {
+        log(level::critical, fmt, std::forward<Args>(args)...);
     }
 
 #ifdef SPDLOG_WCHAR_TO_UTF8_SUPPORT
-#ifndef _WIN32
-#error SPDLOG_WCHAR_TO_UTF8_SUPPORT only supported on windows
-#else
+    template <typename... Args>
+    void log(source_loc loc, level::level_enum lvl, wformat_string_t<Args...> fmt, Args &&...args) {
+        log_(loc, lvl, details::to_string_view(fmt), std::forward<Args>(args)...);
+    }
 
-    template<typename... Args>
-    void log(source_loc loc, level::level_enum lvl, wstring_view_t fmt, const Args &... args)
-    {
+    template <typename... Args>
+    void log(level::level_enum lvl, wformat_string_t<Args...> fmt, Args &&...args) {
+        log(source_loc{}, lvl, fmt, std::forward<Args>(args)...);
+    }
+
+    void log(log_clock::time_point log_time,
+             source_loc loc,
+             level::level_enum lvl,
+             wstring_view_t msg) {
         bool log_enabled = should_log(lvl);
         bool traceback_enabled = tracer_.enabled();
-        if (!log_enabled && !traceback_enabled)
-        {
-            return;
-        }
-        SPDLOG_TRY
-        {
-            // format to wmemory_buffer and convert to utf8
-            fmt::wmemory_buffer wbuf;
-            fmt::format_to(wbuf, fmt, args...);
-
-            memory_buf_t buf;
-            details::os::wstr_to_utf8buf(wstring_view_t(wbuf.data(), wbuf.size()), buf);
-            details::log_msg log_msg(loc, name_, lvl, string_view_t(buf.data(), buf.size()));
-            log_it_(log_msg, log_enabled, traceback_enabled);
-        }
-        SPDLOG_LOGGER_CATCH()
-    }
-
-    template<typename... Args>
-    void log(level::level_enum lvl, wstring_view_t fmt, const Args &... args)
-    {
-        log(source_loc{}, lvl, fmt, args...);
-    }
-
-    template<typename... Args>
-    void trace(wstring_view_t fmt, const Args &... args)
-    {
-        log(level::trace, fmt, args...);
-    }
-
-    template<typename... Args>
-    void debug(wstring_view_t fmt, const Args &... args)
-    {
-        log(level::debug, fmt, args...);
-    }
-
-    template<typename... Args>
-    void info(wstring_view_t fmt, const Args &... args)
-    {
-        log(level::info, fmt, args...);
-    }
-
-    template<typename... Args>
-    void warn(wstring_view_t fmt, const Args &... args)
-    {
-        log(level::warn, fmt, args...);
-    }
-
-    template<typename... Args>
-    void error(wstring_view_t fmt, const Args &... args)
-    {
-        log(level::err, fmt, args...);
-    }
-
-    template<typename... Args>
-    void critical(wstring_view_t fmt, const Args &... args)
-    {
-        log(level::critical, fmt, args...);
-    }
-
-    // T can be statically converted to wstring_view
-    template<class T, typename std::enable_if<is_convertible_to_wstring_view<const T &>::value, T>::type * = nullptr>
-    void log(source_loc loc, level::level_enum lvl, const T &msg)
-    {
-        bool log_enabled = should_log(lvl);
-        bool traceback_enabled = tracer_.enabled();
-        if (!log_enabled && !traceback_enabled)
-        {
+        if (!log_enabled && !traceback_enabled) {
             return;
         }
 
-        SPDLOG_TRY
-        {
-            memory_buf_t buf;
-            details::os::wstr_to_utf8buf(msg, buf);
-            details::log_msg log_msg(loc, name_, lvl, string_view_t(buf.data(), buf.size()));
-            log_it_(log_msg, log_enabled, traceback_enabled);
-        }
-        SPDLOG_LOGGER_CATCH()
+        memory_buf_t buf;
+        details::os::wstr_to_utf8buf(wstring_view_t(msg.data(), msg.size()), buf);
+        details::log_msg log_msg(log_time, loc, name_, lvl, string_view_t(buf.data(), buf.size()));
+        log_it_(log_msg, log_enabled, traceback_enabled);
+    }
+
+    void log(source_loc loc, level::level_enum lvl, wstring_view_t msg) {
+        bool log_enabled = should_log(lvl);
+        bool traceback_enabled = tracer_.enabled();
+        if (!log_enabled && !traceback_enabled) {
+            return;
+        }
+
+        memory_buf_t buf;
+        details::os::wstr_to_utf8buf(wstring_view_t(msg.data(), msg.size()), buf);
+        details::log_msg log_msg(loc, name_, lvl, string_view_t(buf.data(), buf.size()));
+        log_it_(log_msg, log_enabled, traceback_enabled);
+    }
+
+    void log(level::level_enum lvl, wstring_view_t msg) { log(source_loc{}, lvl, msg); }
+
+    template <typename... Args>
+    void trace(wformat_string_t<Args...> fmt, Args &&...args) {
+        log(level::trace, fmt, std::forward<Args>(args)...);
+    }
+
+    template <typename... Args>
+    void debug(wformat_string_t<Args...> fmt, Args &&...args) {
+        log(level::debug, fmt, std::forward<Args>(args)...);
+    }
+
+    template <typename... Args>
+    void info(wformat_string_t<Args...> fmt, Args &&...args) {
+        log(level::info, fmt, std::forward<Args>(args)...);
+    }
+
+    template <typename... Args>
+    void warn(wformat_string_t<Args...> fmt, Args &&...args) {
+        log(level::warn, fmt, std::forward<Args>(args)...);
+    }
+
+    template <typename... Args>
+    void error(wformat_string_t<Args...> fmt, Args &&...args) {
+        log(level::err, fmt, std::forward<Args>(args)...);
+    }
+
+    template <typename... Args>
+    void critical(wformat_string_t<Args...> fmt, Args &&...args) {
+        log(level::critical, fmt, std::forward<Args>(args)...);
+    }
+#endif
+
+    template <typename T>
+    void trace(const T &msg) {
+        log(level::trace, msg);
+    }
+
+    template <typename T>
+    void debug(const T &msg) {
+        log(level::debug, msg);
+    }
+
+    template <typename T>
+    void info(const T &msg) {
+        log(level::info, msg);
+    }
+
+    template <typename T>
+    void warn(const T &msg) {
+        log(level::warn, msg);
+    }
+
+    template <typename T>
+    void error(const T &msg) {
+        log(level::err, msg);
+    }
+
+    template <typename T>
+    void critical(const T &msg) {
+        log(level::critical, msg);
     }
-#endif // _WIN32
-#endif // SPDLOG_WCHAR_TO_UTF8_SUPPORT
 
     // return true logging is enabled for the given level.
-    bool should_log(level::level_enum msg_level) const
-    {
+    bool should_log(level::level_enum msg_level) const {
         return msg_level >= level_.load(std::memory_order_relaxed);
     }
 
     // return true if backtrace logging is enabled.
-    bool should_backtrace() const
-    {
-        return tracer_.enabled();
-    }
+    bool should_backtrace() const { return tracer_.enabled(); }
 
     void set_level(level::level_enum log_level);
 
@@ -338,6 +276,10 @@ public:
     // each sink will get a separate instance of the formatter object.
     void set_formatter(std::unique_ptr<formatter> f);
 
+    // set formatting for the sinks in this logger.
+    // equivalent to
+    //     set_formatter(make_unique<pattern_formatter>(pattern, time_type))
+    // Note: each sink will get a new instance of a formatter object, replacing the old one.
     void set_pattern(std::string pattern, pattern_time_type time_type = pattern_time_type::local);
 
     // backtrace support.
@@ -370,23 +312,68 @@ protected:
     err_handler custom_err_handler_{nullptr};
     details::backtracer tracer_;
 
+    // common implementation for after templated public api has been resolved
+    template <typename... Args>
+    void log_(source_loc loc, level::level_enum lvl, string_view_t fmt, Args &&...args) {
+        bool log_enabled = should_log(lvl);
+        bool traceback_enabled = tracer_.enabled();
+        if (!log_enabled && !traceback_enabled) {
+            return;
+        }
+        SPDLOG_TRY {
+            memory_buf_t buf;
+#ifdef SPDLOG_USE_STD_FORMAT
+            fmt_lib::vformat_to(std::back_inserter(buf), fmt, fmt_lib::make_format_args(args...));
+#else
+            fmt::vformat_to(fmt::appender(buf), fmt, fmt::make_format_args(args...));
+#endif
+
+            details::log_msg log_msg(loc, name_, lvl, string_view_t(buf.data(), buf.size()));
+            log_it_(log_msg, log_enabled, traceback_enabled);
+        }
+        SPDLOG_LOGGER_CATCH(loc)
+    }
+
+#ifdef SPDLOG_WCHAR_TO_UTF8_SUPPORT
+    template <typename... Args>
+    void log_(source_loc loc, level::level_enum lvl, wstring_view_t fmt, Args &&...args) {
+        bool log_enabled = should_log(lvl);
+        bool traceback_enabled = tracer_.enabled();
+        if (!log_enabled && !traceback_enabled) {
+            return;
+        }
+        SPDLOG_TRY {
+            // format to wmemory_buffer and convert to utf8
+            wmemory_buf_t wbuf;
+            fmt_lib::vformat_to(std::back_inserter(wbuf), fmt,
+                                fmt_lib::make_format_args<fmt_lib::wformat_context>(args...));
+
+            memory_buf_t buf;
+            details::os::wstr_to_utf8buf(wstring_view_t(wbuf.data(), wbuf.size()), buf);
+            details::log_msg log_msg(loc, name_, lvl, string_view_t(buf.data(), buf.size()));
+            log_it_(log_msg, log_enabled, traceback_enabled);
+        }
+        SPDLOG_LOGGER_CATCH(loc)
+    }
+#endif  // SPDLOG_WCHAR_TO_UTF8_SUPPORT
+
     // log the given message (if the given log level is high enough),
     // and save backtrace (if backtrace is enabled).
     void log_it_(const details::log_msg &log_msg, bool log_enabled, bool traceback_enabled);
     virtual void sink_it_(const details::log_msg &msg);
     virtual void flush_();
     void dump_backtrace_();
-    bool should_flush_(const details::log_msg &msg);
+    bool should_flush_(const details::log_msg &msg) const;
 
     // handle errors during logging.
     // default handler prints the error to stderr at max rate of 1 message/sec.
-    void err_handler_(const std::string &msg);
+    void err_handler_(const std::string &msg) const;
 };
 
-void swap(logger &a, logger &b);
+void swap(logger &a, logger &b) noexcept;
 
-} // namespace spdlog
+}  // namespace spdlog
 
 #ifdef SPDLOG_HEADER_ONLY
-#include "logger-inl.h"
+    #include "logger-inl.h"
 #endif

include/spdlog/mdc.h

@@ -0,0 +1,52 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#if defined(SPDLOG_NO_TLS)
+    #error "This header requires thread local storage support, but SPDLOG_NO_TLS is defined."
+#endif
+
+#include <map>
+#include <string>
+
+#include <spdlog/common.h>
+
+// MDC is a simple map of key->string values stored in thread local storage whose content will be
+// printed by the loggers. Note: Not supported in async mode (thread local storage - so the async
+// thread pool have different copy).
+//
+// Usage example:
+// spdlog::mdc::put("mdc_key_1", "mdc_value_1");
+// spdlog::info("Hello, {}", "World!");  // => [2024-04-26 02:08:05.040] [info]
+// [mdc_key_1:mdc_value_1] Hello, World!
+
+namespace spdlog {
+class SPDLOG_API mdc {
+public:
+    using mdc_map_t = std::map<std::string, std::string>;
+
+    static void put(const std::string &key, const std::string &value) {
+        get_context()[key] = value;
+    }
+
+    static std::string get(const std::string &key) {
+        auto &context = get_context();
+        auto it = context.find(key);
+        if (it != context.end()) {
+            return it->second;
+        }
+        return "";
+    }
+
+    static void remove(const std::string &key) { get_context().erase(key); }
+
+    static void clear() { get_context().clear(); }
+
+    static mdc_map_t &get_context() {
+        static thread_local mdc_map_t context;
+        return context;
+    }
+};
+
+}  // namespace spdlog

include/spdlog/pattern_formatter.h

@@ -13,77 +13,67 @@
 #include <memory>
 
 #include <string>
-#include <vector>
 #include <unordered_map>
+#include <vector>
 
 namespace spdlog {
 namespace details {
 
 // padding information.
-struct padding_info
-{
-    enum pad_side
-    {
-        left,
-        right,
-        center
-    };
+struct padding_info {
+    enum class pad_side { left, right, center };
 
     padding_info() = default;
     padding_info(size_t width, padding_info::pad_side side, bool truncate)
-        : width_(width)
-        , side_(side)
-        , truncate_(truncate)
-        , enabled_(true)
-    {}
+        : width_(width),
+          side_(side),
+          truncate_(truncate),
+          enabled_(true) {}
 
-    bool enabled() const
-    {
-        return enabled_;
-    }
+    bool enabled() const { return enabled_; }
     size_t width_ = 0;
-    pad_side side_ = left;
+    pad_side side_ = pad_side::left;
     bool truncate_ = false;
     bool enabled_ = false;
 };
 
-class SPDLOG_API flag_formatter
-{
+class SPDLOG_API flag_formatter {
 public:
     explicit flag_formatter(padding_info padinfo)
-        : padinfo_(padinfo)
-    {}
+        : padinfo_(padinfo) {}
     flag_formatter() = default;
     virtual ~flag_formatter() = default;
-    virtual void format(const details::log_msg &msg, const std::tm &tm_time, memory_buf_t &dest) = 0;
+    virtual void format(const details::log_msg &msg,
+                        const std::tm &tm_time,
+                        memory_buf_t &dest) = 0;
 
 protected:
     padding_info padinfo_;
 };
 
-} // namespace details
+}  // namespace details
 
-class SPDLOG_API custom_flag_formatter : public details::flag_formatter
-{
+class SPDLOG_API custom_flag_formatter : public details::flag_formatter {
 public:
     virtual std::unique_ptr<custom_flag_formatter> clone() const = 0;
 
-    void set_padding_info(details::padding_info padding)
-    {
+    void set_padding_info(const details::padding_info &padding) {
         flag_formatter::padinfo_ = padding;
     }
 };
 
-class SPDLOG_API pattern_formatter final : public formatter
-{
+class SPDLOG_API pattern_formatter final : public formatter {
 public:
     using custom_flags = std::unordered_map<char, std::unique_ptr<custom_flag_formatter>>;
 
-    explicit pattern_formatter(std::string pattern, pattern_time_type time_type = pattern_time_type::local,
-        std::string eol = spdlog::details::os::default_eol, custom_flags custom_user_flags = custom_flags());
+    explicit pattern_formatter(std::string pattern,
+                               pattern_time_type time_type = pattern_time_type::local,
+                               std::string eol = spdlog::details::os::default_eol,
+                               custom_flags custom_user_flags = custom_flags());
 
     // use default pattern is not given
-    explicit pattern_formatter(pattern_time_type time_type = pattern_time_type::local, std::string eol = spdlog::details::os::default_eol);
+    explicit pattern_formatter(pattern_time_type time_type = pattern_time_type::local,
+                               std::string eol = spdlog::details::os::default_eol);
 
     pattern_formatter(const pattern_formatter &other) = delete;
     pattern_formatter &operator=(const pattern_formatter &other) = delete;
@@ -91,36 +81,38 @@ public:
     std::unique_ptr<formatter> clone() const override;
     void format(const details::log_msg &msg, memory_buf_t &dest) override;
 
-    template<typename T, typename... Args>
-    pattern_formatter &add_flag(char flag, const Args &... args)
-    {
-        custom_handlers_[flag] = details::make_unique<T>(args...);
+    template <typename T, typename... Args>
+    pattern_formatter &add_flag(char flag, Args &&...args) {
+        custom_handlers_[flag] = details::make_unique<T>(std::forward<Args>(args)...);
         return *this;
     }
     void set_pattern(std::string pattern);
+    void need_localtime(bool need = true);
 
 private:
     std::string pattern_;
     std::string eol_;
     pattern_time_type pattern_time_type_;
+    bool need_localtime_;
     std::tm cached_tm_;
     std::chrono::seconds last_log_secs_;
     std::vector<std::unique_ptr<details::flag_formatter>> formatters_;
     custom_flags custom_handlers_;
 
     std::tm get_time_(const details::log_msg &msg);
-    template<typename Padder>
+    template <typename Padder>
     void handle_flag_(char flag, details::padding_info padding);
 
     // Extract given pad spec (e.g. %8X)
     // Advance the given it pass the end of the padding spec found (if any)
     // Return padding.
-    static details::padding_info handle_padspec_(std::string::const_iterator &it, std::string::const_iterator end);
+    static details::padding_info handle_padspec_(std::string::const_iterator &it,
+                                                 std::string::const_iterator end);
 
     void compile_pattern_(const std::string &pattern);
 };
-} // namespace spdlog
+}  // namespace spdlog
 
 #ifdef SPDLOG_HEADER_ONLY
-#include "pattern_formatter-inl.h"
+    #include "pattern_formatter-inl.h"
 #endif

include/spdlog/sinks/android_sink.h

@@ -5,90 +5,102 @@
 
 #ifdef __ANDROID__
 
-#include <spdlog/details/fmt_helper.h>
-#include <spdlog/details/null_mutex.h>
-#include <spdlog/details/os.h>
-#include <spdlog/sinks/base_sink.h>
-#include <spdlog/details/synchronous_factory.h>
+    #include <spdlog/details/fmt_helper.h>
+    #include <spdlog/details/null_mutex.h>
+    #include <spdlog/details/os.h>
+    #include <spdlog/details/synchronous_factory.h>
+    #include <spdlog/sinks/base_sink.h>
 
-#include <android/log.h>
-#include <chrono>
-#include <mutex>
-#include <string>
-#include <thread>
+    #include <android/log.h>
+    #include <chrono>
+    #include <mutex>
+    #include <string>
+    #include <thread>
+    #include <type_traits>
 
-#if !defined(SPDLOG_ANDROID_RETRIES)
-#define SPDLOG_ANDROID_RETRIES 2
-#endif
+    #if !defined(SPDLOG_ANDROID_RETRIES)
+        #define SPDLOG_ANDROID_RETRIES 2
+    #endif
 
 namespace spdlog {
 namespace sinks {
 
 /*
- * Android sink (logging using __android_log_write)
+ * Android sink
+ * (logging using __android_log_write or __android_log_buf_write depending on the specified
+ * BufferID)
  */
-template<typename Mutex>
-class android_sink final : public base_sink<Mutex>
-{
+template <typename Mutex, int BufferID = log_id::LOG_ID_MAIN>
+class android_sink final : public base_sink<Mutex> {
 public:
     explicit android_sink(std::string tag = "spdlog", bool use_raw_msg = false)
-        : tag_(std::move(tag))
-        , use_raw_msg_(use_raw_msg)
-    {}
+        : tag_(std::move(tag)),
+          use_raw_msg_(use_raw_msg) {}
 
 protected:
-    void sink_it_(const details::log_msg &msg) override
-    {
+    void sink_it_(const details::log_msg &msg) override {
         const android_LogPriority priority = convert_to_android_(msg.level);
         memory_buf_t formatted;
-        if (use_raw_msg_)
-        {
+        if (use_raw_msg_) {
             details::fmt_helper::append_string_view(msg.payload, formatted);
-        }
-        else
-        {
+        } else {
             base_sink<Mutex>::formatter_->format(msg, formatted);
         }
         formatted.push_back('\0');
         const char *msg_output = formatted.data();
 
         // See system/core/liblog/logger_write.c for explanation of return value
-        int ret = __android_log_write(priority, tag_.c_str(), msg_output);
+        int ret = android_log(priority, tag_.c_str(), msg_output);
+        if (ret == -EPERM) {
+            return;  // !__android_log_is_loggable
+        }
         int retry_count = 0;
-        while ((ret == -11 /*EAGAIN*/) && (retry_count < SPDLOG_ANDROID_RETRIES))
-        {
+        while ((ret == -11 /*EAGAIN*/) && (retry_count < SPDLOG_ANDROID_RETRIES)) {
             details::os::sleep_for_millis(5);
-            ret = __android_log_write(priority, tag_.c_str(), msg_output);
+            ret = android_log(priority, tag_.c_str(), msg_output);
             retry_count++;
         }
 
-        if (ret < 0)
-        {
-            throw_spdlog_ex("__android_log_write() failed", ret);
+        if (ret < 0) {
+            throw_spdlog_ex("logging to Android failed", ret);
         }
     }
 
     void flush_() override {}
 
 private:
-    static android_LogPriority convert_to_android_(spdlog::level::level_enum level)
-    {
-        switch (level)
-        {
-        case spdlog::level::trace:
-            return ANDROID_LOG_VERBOSE;
-        case spdlog::level::debug:
-            return ANDROID_LOG_DEBUG;
-        case spdlog::level::info:
-            return ANDROID_LOG_INFO;
-        case spdlog::level::warn:
-            return ANDROID_LOG_WARN;
-        case spdlog::level::err:
-            return ANDROID_LOG_ERROR;
-        case spdlog::level::critical:
-            return ANDROID_LOG_FATAL;
-        default:
-            return ANDROID_LOG_DEFAULT;
+    // There might be liblog versions used, that do not support __android_log_buf_write. So we only
+    // compile and link against
+    // __android_log_buf_write, if user explicitly provides a non-default log buffer. Otherwise,
+    // when using the default log buffer, always log via __android_log_write.
+    template <int ID = BufferID>
+    typename std::enable_if<ID == static_cast<int>(log_id::LOG_ID_MAIN), int>::type android_log(
+        int prio, const char *tag, const char *text) {
+        return __android_log_write(prio, tag, text);
+    }
+
+    template <int ID = BufferID>
+    typename std::enable_if<ID != static_cast<int>(log_id::LOG_ID_MAIN), int>::type android_log(
+        int prio, const char *tag, const char *text) {
+        return __android_log_buf_write(ID, prio, tag, text);
+    }
+
+    static android_LogPriority convert_to_android_(spdlog::level::level_enum level) {
+        switch (level) {
+            case spdlog::level::trace:
+                return ANDROID_LOG_VERBOSE;
+            case spdlog::level::debug:
+                return ANDROID_LOG_DEBUG;
+            case spdlog::level::info:
+                return ANDROID_LOG_INFO;
+            case spdlog::level::warn:
+                return ANDROID_LOG_WARN;
+            case spdlog::level::err:
+                return ANDROID_LOG_ERROR;
+            case spdlog::level::critical:
+                return ANDROID_LOG_FATAL;
+            default:
+                return ANDROID_LOG_DEFAULT;
         }
     }
 
@@ -98,22 +110,28 @@ private:
 
 using android_sink_mt = android_sink<std::mutex>;
 using android_sink_st = android_sink<details::null_mutex>;
-} // namespace sinks
+
+template <int BufferId = log_id::LOG_ID_MAIN>
+using android_sink_buf_mt = android_sink<std::mutex, BufferId>;
+template <int BufferId = log_id::LOG_ID_MAIN>
+using android_sink_buf_st = android_sink<details::null_mutex, BufferId>;
+
+}  // namespace sinks
 
 // Create and register android syslog logger
 
-template<typename Factory = spdlog::synchronous_factory>
-inline std::shared_ptr<logger> android_logger_mt(const std::string &logger_name, const std::string &tag = "spdlog")
-{
+template <typename Factory = spdlog::synchronous_factory>
+inline std::shared_ptr<logger> android_logger_mt(const std::string &logger_name,
+                                                 const std::string &tag = "spdlog") {
     return Factory::template create<sinks::android_sink_mt>(logger_name, tag);
 }
 
-template<typename Factory = spdlog::synchronous_factory>
-inline std::shared_ptr<logger> android_logger_st(const std::string &logger_name, const std::string &tag = "spdlog")
-{
+template <typename Factory = spdlog::synchronous_factory>
+inline std::shared_ptr<logger> android_logger_st(const std::string &logger_name,
+                                                 const std::string &tag = "spdlog") {
     return Factory::template create<sinks::android_sink_st>(logger_name, tag);
 }
 
-} // namespace spdlog
+}  // namespace spdlog
 
-#endif // __ANDROID__
+#endif  // __ANDROID__

include/spdlog/sinks/ansicolor_sink-inl.h

@@ -4,42 +4,41 @@
 #pragma once
 
 #ifndef SPDLOG_HEADER_ONLY
-#include <spdlog/sinks/ansicolor_sink.h>
+    #include <spdlog/sinks/ansicolor_sink.h>
 #endif
 
-#include <spdlog/pattern_formatter.h>
 #include <spdlog/details/os.h>
+#include <spdlog/pattern_formatter.h>
 
 namespace spdlog {
 namespace sinks {
 
-template<typename ConsoleMutex>
+template <typename ConsoleMutex>
 SPDLOG_INLINE ansicolor_sink<ConsoleMutex>::ansicolor_sink(FILE *target_file, color_mode mode)
-    : target_file_(target_file)
-    , mutex_(ConsoleMutex::mutex())
-    , formatter_(details::make_unique<spdlog::pattern_formatter>())
+    : target_file_(target_file),
+      mutex_(ConsoleMutex::mutex()),
+      formatter_(details::make_unique<spdlog::pattern_formatter>())
 
 {
-    set_color_mode(mode);
-    colors_[level::trace] = to_string_(white);
-    colors_[level::debug] = to_string_(cyan);
-    colors_[level::info] = to_string_(green);
-    colors_[level::warn] = to_string_(yellow_bold);
-    colors_[level::err] = to_string_(red_bold);
-    colors_[level::critical] = to_string_(bold_on_red);
-    colors_[level::off] = to_string_(reset);
+    set_color_mode_(mode);
+    colors_.at(level::trace) = to_string_(white);
+    colors_.at(level::debug) = to_string_(cyan);
+    colors_.at(level::info) = to_string_(green);
+    colors_.at(level::warn) = to_string_(yellow_bold);
+    colors_.at(level::err) = to_string_(red_bold);
+    colors_.at(level::critical) = to_string_(bold_on_red);
+    colors_.at(level::off) = to_string_(reset);
 }
 
-template<typename ConsoleMutex>
-SPDLOG_INLINE void ansicolor_sink<ConsoleMutex>::set_color(level::level_enum color_level, string_view_t color)
-{
+template <typename ConsoleMutex>
+SPDLOG_INLINE void ansicolor_sink<ConsoleMutex>::set_color(level::level_enum color_level,
+                                                           string_view_t color) {
     std::lock_guard<mutex_t> lock(mutex_);
-    colors_[color_level] = to_string_(color);
+    colors_.at(static_cast<size_t>(color_level)) = to_string_(color);
 }
 
-template<typename ConsoleMutex>
-SPDLOG_INLINE void ansicolor_sink<ConsoleMutex>::log(const details::log_msg &msg)
-{
+template <typename ConsoleMutex>
+SPDLOG_INLINE void ansicolor_sink<ConsoleMutex>::log(const details::log_msg &msg) {
     // Wrap the originally formatted message in color codes.
     // If color is not supported in the terminal, log as is instead.
     std::lock_guard<mutex_t> lock(mutex_);
@@ -47,97 +46,97 @@ SPDLOG_INLINE void ansicolor_sink<ConsoleMutex>::log(const details::log_msg &msg
     msg.color_range_end = 0;
     memory_buf_t formatted;
     formatter_->format(msg, formatted);
-    if (should_do_colors_ && msg.color_range_end > msg.color_range_start)
-    {
+    if (should_do_colors_ && msg.color_range_end > msg.color_range_start) {
         // before color range
         print_range_(formatted, 0, msg.color_range_start);
         // in color range
-        print_ccode_(colors_[msg.level]);
+        print_ccode_(colors_.at(static_cast<size_t>(msg.level)));
         print_range_(formatted, msg.color_range_start, msg.color_range_end);
         print_ccode_(reset);
         // after color range
         print_range_(formatted, msg.color_range_end, formatted.size());
-    }
-    else // no color
+    } else  // no color
     {
         print_range_(formatted, 0, formatted.size());
     }
     fflush(target_file_);
 }
 
-template<typename ConsoleMutex>
-SPDLOG_INLINE void ansicolor_sink<ConsoleMutex>::flush()
-{
+template <typename ConsoleMutex>
+SPDLOG_INLINE void ansicolor_sink<ConsoleMutex>::flush() {
     std::lock_guard<mutex_t> lock(mutex_);
     fflush(target_file_);
 }
 
-template<typename ConsoleMutex>
-SPDLOG_INLINE void ansicolor_sink<ConsoleMutex>::set_pattern(const std::string &pattern)
-{
+template <typename ConsoleMutex>
+SPDLOG_INLINE void ansicolor_sink<ConsoleMutex>::set_pattern(const std::string &pattern) {
     std::lock_guard<mutex_t> lock(mutex_);
     formatter_ = std::unique_ptr<spdlog::formatter>(new pattern_formatter(pattern));
 }
 
-template<typename ConsoleMutex>
-SPDLOG_INLINE void ansicolor_sink<ConsoleMutex>::set_formatter(std::unique_ptr<spdlog::formatter> sink_formatter)
-{
+template <typename ConsoleMutex>
+SPDLOG_INLINE void ansicolor_sink<ConsoleMutex>::set_formatter(
+    std::unique_ptr<spdlog::formatter> sink_formatter) {
     std::lock_guard<mutex_t> lock(mutex_);
     formatter_ = std::move(sink_formatter);
 }
 
-template<typename ConsoleMutex>
-SPDLOG_INLINE bool ansicolor_sink<ConsoleMutex>::should_color()
-{
+template <typename ConsoleMutex>
+SPDLOG_INLINE bool ansicolor_sink<ConsoleMutex>::should_color() const {
     return should_do_colors_;
 }
 
-template<typename ConsoleMutex>
-SPDLOG_INLINE void ansicolor_sink<ConsoleMutex>::set_color_mode(color_mode mode)
-{
-    switch (mode)
-    {
-    case color_mode::always:
-        should_do_colors_ = true;
-        return;
-    case color_mode::automatic:
-        should_do_colors_ = details::os::in_terminal(target_file_) && details::os::is_color_terminal();
-        return;
-    case color_mode::never:
-        should_do_colors_ = false;
-        return;
+template <typename ConsoleMutex>
+SPDLOG_INLINE void ansicolor_sink<ConsoleMutex>::set_color_mode(color_mode mode) {
+    std::lock_guard<mutex_t> lock(mutex_);
+    set_color_mode_(mode);
+}
+
+template <typename ConsoleMutex>
+SPDLOG_INLINE void ansicolor_sink<ConsoleMutex>::set_color_mode_(color_mode mode) {
+    switch (mode) {
+        case color_mode::always:
+            should_do_colors_ = true;
+            return;
+        case color_mode::automatic:
+            should_do_colors_ =
+                details::os::in_terminal(target_file_) && details::os::is_color_terminal();
+            return;
+        case color_mode::never:
+            should_do_colors_ = false;
+            return;
+        default:
+            should_do_colors_ = false;
     }
 }
 
-template<typename ConsoleMutex>
-SPDLOG_INLINE void ansicolor_sink<ConsoleMutex>::print_ccode_(const string_view_t &color_code)
-{
-    fwrite(color_code.data(), sizeof(char), color_code.size(), target_file_);
+template <typename ConsoleMutex>
+SPDLOG_INLINE void ansicolor_sink<ConsoleMutex>::print_ccode_(
+    const string_view_t &color_code) const {
+    details::os::fwrite_bytes(color_code.data(), color_code.size(), target_file_);
 }
 
-template<typename ConsoleMutex>
-SPDLOG_INLINE void ansicolor_sink<ConsoleMutex>::print_range_(const memory_buf_t &formatted, size_t start, size_t end)
-{
-    fwrite(formatted.data() + start, sizeof(char), end - start, target_file_);
+template <typename ConsoleMutex>
+SPDLOG_INLINE void ansicolor_sink<ConsoleMutex>::print_range_(const memory_buf_t &formatted,
+                                                              size_t start,
+                                                              size_t end) const {
+    details::os::fwrite_bytes(formatted.data() + start, end - start, target_file_);
 }
 
-template<typename ConsoleMutex>
-SPDLOG_INLINE std::string ansicolor_sink<ConsoleMutex>::to_string_(const string_view_t &sv)
-{
+template <typename ConsoleMutex>
+SPDLOG_INLINE std::string ansicolor_sink<ConsoleMutex>::to_string_(const string_view_t &sv) {
     return std::string(sv.data(), sv.size());
 }
 
 // ansicolor_stdout_sink
-template<typename ConsoleMutex>
+template <typename ConsoleMutex>
 SPDLOG_INLINE ansicolor_stdout_sink<ConsoleMutex>::ansicolor_stdout_sink(color_mode mode)
-    : ansicolor_sink<ConsoleMutex>(stdout, mode)
-{}
+    : ansicolor_sink<ConsoleMutex>(stdout, mode) {}
 
 // ansicolor_stderr_sink
-template<typename ConsoleMutex>
+template <typename ConsoleMutex>
 SPDLOG_INLINE ansicolor_stderr_sink<ConsoleMutex>::ansicolor_stderr_sink(color_mode mode)
-    : ansicolor_sink<ConsoleMutex>(stderr, mode)
-{}
+    : ansicolor_sink<ConsoleMutex>(stderr, mode) {}
 
-} // namespace sinks
-} // namespace spdlog
+}  // namespace sinks
+}  // namespace spdlog

include/spdlog/sinks/ansicolor_sink.h

@@ -3,13 +3,13 @@
 
 #pragma once
 
+#include <array>
+#include <memory>
+#include <mutex>
 #include <spdlog/details/console_globals.h>
 #include <spdlog/details/null_mutex.h>
 #include <spdlog/sinks/sink.h>
-#include <memory>
-#include <mutex>
 #include <string>
-#include <array>
 
 namespace spdlog {
 namespace sinks {
@@ -21,9 +21,8 @@ namespace sinks {
  * If no color terminal detected, omit the escape codes.
  */
 
-template<typename ConsoleMutex>
-class ansicolor_sink : public sink
-{
+template <typename ConsoleMutex>
+class ansicolor_sink : public sink {
 public:
     using mutex_t = typename ConsoleMutex::mutex_t;
     ansicolor_sink(FILE *target_file, color_mode mode);
@@ -37,11 +36,11 @@ public:
 
     void set_color(level::level_enum color_level, string_view_t color);
     void set_color_mode(color_mode mode);
-    bool should_color();
+    bool should_color() const;
 
     void log(const details::log_msg &msg) override;
     void flush() override;
-    void set_pattern(const std::string &pattern) final;
+    void set_pattern(const std::string &pattern) override;
     void set_formatter(std::unique_ptr<spdlog::formatter> sink_formatter) override;
 
     // Formatting codes
@@ -85,21 +84,20 @@ private:
     bool should_do_colors_;
     std::unique_ptr<spdlog::formatter> formatter_;
     std::array<std::string, level::n_levels> colors_;
-    void print_ccode_(const string_view_t &color_code);
-    void print_range_(const memory_buf_t &formatted, size_t start, size_t end);
+    void set_color_mode_(color_mode mode);
+    void print_ccode_(const string_view_t &color_code) const;
+    void print_range_(const memory_buf_t &formatted, size_t start, size_t end) const;
     static std::string to_string_(const string_view_t &sv);
 };
 
-template<typename ConsoleMutex>
-class ansicolor_stdout_sink : public ansicolor_sink<ConsoleMutex>
-{
+template <typename ConsoleMutex>
+class ansicolor_stdout_sink : public ansicolor_sink<ConsoleMutex> {
 public:
     explicit ansicolor_stdout_sink(color_mode mode = color_mode::automatic);
 };
 
-template<typename ConsoleMutex>
-class ansicolor_stderr_sink : public ansicolor_sink<ConsoleMutex>
-{
+template <typename ConsoleMutex>
+class ansicolor_stderr_sink : public ansicolor_sink<ConsoleMutex> {
 public:
     explicit ansicolor_stderr_sink(color_mode mode = color_mode::automatic);
 };
@@ -110,9 +108,9 @@ using ansicolor_stdout_sink_st = ansicolor_stdout_sink<details::console_nullmute
 using ansicolor_stderr_sink_mt = ansicolor_stderr_sink<details::console_mutex>;
 using ansicolor_stderr_sink_st = ansicolor_stderr_sink<details::console_nullmutex>;
 
-} // namespace sinks
-} // namespace spdlog
+}  // namespace sinks
+}  // namespace spdlog
 
 #ifdef SPDLOG_HEADER_ONLY
-#include "ansicolor_sink-inl.h"
+    #include "ansicolor_sink-inl.h"
 #endif