Update version.h

remove constexpr on level_string_views to fix compilation on C++17 fr…

.travis.yml

@@ -101,10 +101,10 @@ script:
       -DCMAKE_CXX_STANDARD=$CPP \
       -DSPDLOG_BUILD_EXAMPLE=ON \
       -DSPDLOG_BUILD_EXAMPLE_HO=ON \
-      -DSPDLOG_ENABLE_WARNINGS=ON \
+      -DSPDLOG_BUILD_WARNINGS=ON \
       -DSPDLOG_BUILD_BENCH=OFF \
       -DSPDLOG_BUILD_TESTS=ON \
-      -DSPDLOG_BUILD_TESTS_HO=OFf \
+      -DSPDLOG_BUILD_TESTS_HO=OFF \
       -DSPDLOG_SANITIZE_ADDRESS=$ASAN 
       
   - make VERBOSE=1 -j2

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)
 
 # ---------------------------------------------------------------------------------------
 # Start spdlog project
@@ -38,9 +30,14 @@ if(NOT CMAKE_CXX_STANDARD)
     set(CMAKE_CXX_STANDARD_REQUIRED ON)
 endif()
 
+# make sure __cplusplus is defined when using msvc
+if(MSVC)
+    string(APPEND CMAKE_CXX_FLAGS " /Zc:__cplusplus")
+endif()
+
 set(CMAKE_CXX_EXTENSIONS OFF)
 
-if(CMAKE_SYSTEM_NAME MATCHES "CYGWIN")
+if(CMAKE_SYSTEM_NAME MATCHES "CYGWIN" OR CMAKE_SYSTEM_NAME MATCHES "MSYS")
     set(CMAKE_CXX_EXTENSIONS ON)
 endif()
 
@@ -108,6 +105,7 @@ 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)
 
 # clang-tidy
 if(${CMAKE_VERSION} VERSION_GREATER "3.5")
@@ -131,16 +129,16 @@ if(NOT SPDLOG_FMT_EXTERNAL AND NOT SPDLOG_FMT_EXTERNAL_HO)
     list(APPEND SPDLOG_SRCS src/fmt.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(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)
@@ -180,7 +178,7 @@ 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)
@@ -197,52 +195,37 @@ if(SPDLOG_FMT_EXTERNAL OR SPDLOG_FMT_EXTERNAL_HO)
     set(PKG_CONFIG_REQUIRES fmt) # add dependency to pkg-config
 endif()
 
+# ---------------------------------------------------------------------------------------
+# Add required libraries for Android CMake build
+# ---------------------------------------------------------------------------------------
+if (ANDROID)
+    target_link_libraries(spdlog PUBLIC log)
+    target_link_libraries(spdlog_header_only INTERFACE log)
+endif ()
+
 # ---------------------------------------------------------------------------------------
 # Misc definitions according to tweak options
 # ---------------------------------------------------------------------------------------
-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)
+set(SPDLOG_WCHAR_TO_UTF8_SUPPORT ${SPDLOG_WCHAR_SUPPORT})
+foreach(
+    SPDLOG_OPTION
+    SPDLOG_WCHAR_TO_UTF8_SUPPORT
+    SPDLOG_WCHAR_FILENAMES
+    SPDLOG_NO_EXCEPTIONS
+    SPDLOG_CLOCK_COARSE
+    SPDLOG_PREVENT_CHILD_FD
+    SPDLOG_NO_THREAD_ID
+    SPDLOG_NO_TLS
+    SPDLOG_NO_ATOMIC_LEVELS
+    SPDLOG_DISABLE_DEFAULT_LOGGER)
+    if(${SPDLOG_OPTION})
+        target_compile_definitions(spdlog PUBLIC ${SPDLOG_OPTION})
+        target_compile_definitions(spdlog_header_only INTERFACE ${SPDLOG_OPTION})
     endif()
-endif()
+endforeach()
 
-if(SPDLOG_CLOCK_COARSE)
-    target_compile_definitions(spdlog PRIVATE SPDLOG_CLOCK_COARSE)
-    target_compile_definitions(spdlog_header_only INTERFACE SPDLOG_CLOCK_COARSE)
-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)
-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)
-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)
+if(SPDLOG_NO_EXCEPTIONS AND NOT MSVC)
+    target_compile_options(spdlog PRIVATE -fno-exceptions)
 endif()
 
 # ---------------------------------------------------------------------------------------
@@ -322,3 +305,4 @@ if(SPDLOG_INSTALL)
     # ---------------------------------------------------------------------------------------
     include(cmake/spdlogCPack.cmake)
 endif()
+

README.md

@@ -25,12 +25,14 @@ $ cmake .. && make -j
 * Homebrew: `brew install spdlog`
 * MacPorts: `sudo port install spdlog`
 * FreeBSD:  `cd /usr/ports/devel/spdlog/ && make install clean`
-* Fedora: `yum install spdlog`
+* Fedora: `dnf install spdlog`
 * Gentoo: `emerge dev-libs/spdlog`
 * Arch Linux: `pacman -S spdlog`
 * vcpkg: `vcpkg install spdlog`
 * conan: `spdlog/[>=1.4.1]`
 * conda: `conda install -c conda-forge spdlog`
+* build2: ```depends: spdlog ^1.8.2```
+
 
 
 ## Features
@@ -45,7 +47,8 @@ $ cmake .. && make -j
     * Daily log files.
     * Console logging (colors supported).
     * syslog.
-    * Windows debugger (```OutputDebugString(..)```)
+    * Windows event log.
+    * 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.
@@ -56,7 +59,6 @@ $ cmake .. && make -j
 #### Basic usage
 ```c++
 #include "spdlog/spdlog.h"
-#include "spdlog/sinks/basic_file_sink.h"
 
 int main() 
 {
@@ -79,10 +81,6 @@ int main()
     // define SPDLOG_ACTIVE_LEVEL to desired level
     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);            
 }
 
 ```
@@ -169,6 +167,20 @@ 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++
@@ -179,6 +191,7 @@ spdlog::flush_every(std::chrono::seconds(3));
 // {: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.
+// {:a} - show ASCII if :n is not set.
 
 #include "spdlog/fmt/bin_to_hex.h"
 
@@ -418,6 +431,6 @@ Documentation can be found in the [wiki](https://github.com/gabime/spdlog/wiki/1
 
 ---
 
-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>
+Thanks to [JetBrains](https://www.jetbrains.com/?from=spdlog) for donating product licenses to help develop **spdlog** <a href="https://www.jetbrains.com/?from=spdlog"><img src="logos/jetbrains-variant-4.svg" width="94" align="center" /></a>
 
 

appveyor.yml

@@ -4,32 +4,52 @@ environment:
   matrix:
     - GENERATOR: '"Visual Studio 14 2015"'
       BUILD_TYPE: Debug
-      WCHAR: 'OFF'
       BUILD_SHARED: 'OFF'
+      WCHAR: 'OFF'
+      WCHAR_FILES: 'OFF'
+      BUILD_EXAMPLE: 'ON'
     - GENERATOR: '"Visual Studio 14 2015"'
       BUILD_TYPE: Release
-      WCHAR: 'ON'
       BUILD_SHARED: 'OFF'
+      WCHAR: 'ON'
+      WCHAR_FILES: 'OFF'
+      BUILD_EXAMPLE: 'ON'
     - GENERATOR: '"Visual Studio 14 2015 Win64"'
       BUILD_TYPE: Debug
-      WCHAR: 'ON'
       BUILD_SHARED: 'OFF'
+      WCHAR: 'ON'
+      WCHAR_FILES: 'OFF'
+      BUILD_EXAMPLE: 'ON'
     - GENERATOR: '"Visual Studio 14 2015 Win64"'
       BUILD_TYPE: Release
-      WCHAR: 'ON'
       BUILD_SHARED: 'OFF'
+      WCHAR: 'ON'
+      WCHAR_FILES: 'OFF'
+      BUILD_EXAMPLE: 'ON'
     - GENERATOR: '"Visual Studio 15 2017 Win64"'
       BUILD_TYPE: Debug
+      BUILD_SHARED: 'OFF'
       WCHAR: 'ON'
-      BUILD_SHARED: 'OFF'
+      WCHAR_FILES: 'OFF'
+      BUILD_EXAMPLE: 'ON'
     - GENERATOR: '"Visual Studio 15 2017 Win64"'
       BUILD_TYPE: Release
-      WCHAR: 'OFF'
       BUILD_SHARED: 'OFF'
+      WCHAR: 'OFF'
+      WCHAR_FILES: 'OFF'
+      BUILD_EXAMPLE: 'ON'
     - GENERATOR: '"Visual Studio 15 2017 Win64"'
       BUILD_TYPE: Release
-      WCHAR: 'OFF'
       BUILD_SHARED: 'ON'
+      WCHAR: 'OFF'
+      WCHAR_FILES: 'OFF'
+      BUILD_EXAMPLE: 'ON'
+    - GENERATOR: '"Visual Studio 15 2017 Win64"'
+      BUILD_TYPE: Release
+      BUILD_SHARED: 'ON'
+      WCHAR: 'ON'
+      WCHAR_FILES: 'ON'
+      BUILD_EXAMPLE: 'OFF'
 build_script:
   - cmd: >-
       set
@@ -40,7 +60,7 @@ 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=ON ..
 
       cmake --build . --config %BUILD_TYPE%
 

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 3.10)
 project(spdlog_bench CXX)
 
 if(NOT TARGET spdlog)
@@ -9,7 +9,24 @@ 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 ${CMAKE_VERSION}")
+    if (${CMAKE_VERSION} VERSION_GREATER_EQUAL "3.11.0")
+        # User can fetch googlebenchmark 			
+        message(STATUS "Downloading GoogleBenchmark")
+        include(FetchContent)
+        set(BENCHMARK_ENABLE_GTEST_TESTS OFF CACHE INTERNAL "")
+        # Do not build and run googlebenchmark tests
+        FetchContent_Declare(googlebenchmark
+            GIT_REPOSITORY https://github.com/google/benchmark.git
+            GIT_TAG v1.5.2)
+
+        FetchContent_MakeAvailable(googlebenchmark)
+    else()
+        message(FATAL_ERROR "GoogleBenchmark is missing. Use CMake >= 3.11 or download it")
+    endif()
+endif()
 
 add_executable(bench bench.cpp)
 spdlog_enable_warnings(bench)

bench/async_bench.cpp

@@ -9,7 +9,12 @@
 #include "spdlog/spdlog.h"
 #include "spdlog/async.h"
 #include "spdlog/sinks/basic_file_sink.h"
-#include "spdlog/sinks/stdout_color_sinks.h"
+
+#ifdef SPDLOG_FMT_EXTERNAL
+#include <fmt/locale.h>
+#else
+#include "spdlog/fmt/bundled/locale.h"
+#endif
 
 #include "utils.h"
 #include <atomic>
@@ -29,7 +34,7 @@ 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
+#endif // _MSC_VER
 
 int count_lines(const char *filename)
 {
@@ -48,14 +53,14 @@ int count_lines(const char *filename)
 
 void verify_file(const char *filename, int expected_count)
 {
-    spdlog::info("Verifying {} to contain {:n} line..", filename, 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);
+        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
@@ -98,11 +103,12 @@ int main(int argc, char *argv[])
 
         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(fmt::format(std::locale("en_US.UTF-8"), "Messages     : {:L}", howmany));
+        spdlog::info(fmt::format(std::locale("en_US.UTF-8"), "Threads      : {:L}", threads));
+        spdlog::info(fmt::format(std::locale("en_US.UTF-8"), "Queue        : {:L} slots", queue_size));
+        spdlog::info(fmt::format(
+            std::locale("en_US.UTF-8"), "Queue memory : {:L} x {:L} = {:L} KB ", queue_size, slot_size, (queue_size * slot_size) / 1024));
+        spdlog::info(fmt::format(std::locale("en_US.UTF-8"), "Total iters  : {:L}", iters));
         spdlog::info("-------------------------------------------------");
 
         const char *filename = "logs/basic_async.log";
@@ -175,5 +181,5 @@ void bench_mt(int howmany, std::shared_ptr<spdlog::logger> logger, int thread_co
 
     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(fmt::format(std::locale("en_US.UTF-8"), "Elapsed: {} secs\t {:L}/sec", delta_d, int(howmany / delta_d)));
 }

bench/bench.cpp

@@ -12,6 +12,12 @@
 #include "spdlog/sinks/null_sink.h"
 #include "spdlog/sinks/rotating_file_sink.h"
 
+#ifdef SPDLOG_FMT_EXTERNAL
+#include <fmt/locale.h>
+#else
+#include "spdlog/fmt/bundled/locale.h"
+#endif
+
 #include "utils.h"
 #include <atomic>
 #include <cstdlib> // EXIT_FAILURE
@@ -32,7 +38,7 @@ static const int max_threads = 1000;
 void bench_threaded_logging(size_t threads, int iters)
 {
     spdlog::info("**************************************************************");
-    spdlog::info("Multi threaded: {:n} threads, {:n} messages", threads, iters);
+    spdlog::info(fmt::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);
@@ -68,7 +74,7 @@ void bench_threaded_logging(size_t threads, int iters)
 void bench_single_threaded(int iters)
 {
     spdlog::info("**************************************************************");
-    spdlog::info("Single threaded: {:n} messages", iters);
+    spdlog::info(fmt::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);
@@ -152,7 +158,8 @@ void bench(int howmany, std::shared_ptr<spdlog::logger> log)
     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(
+        fmt::format(std::locale("en_US.UTF-8"), "{:<30} Elapsed: {:0.2f} secs {:>16L}/sec", log->name(), delta_d, int(howmany / delta_d)));
     spdlog::drop(log->name());
 }
 
@@ -182,7 +189,8 @@ void bench_mt(int howmany, std::shared_ptr<spdlog::logger> log, size_t thread_co
 
     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(
+        fmt::format(std::locale("en_US.UTF-8"), "{:<30} Elapsed: {:0.2f} secs {:>16L}/sec", log->name(), delta_d, int(howmany / delta_d)));
     spdlog::drop(log->name());
 }
 
@@ -205,7 +213,7 @@ 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)
@@ -232,7 +240,7 @@ 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

@@ -34,14 +34,14 @@ void bench_formatters()
     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
@@ -52,7 +52,7 @@ void bench_formatters()
     };
     for (auto &pattern : patterns)
     {
-        benchmark::RegisterBenchmark(pattern.c_str(), bench_formatter, pattern)->Iterations(2500000);
+        benchmark::RegisterBenchmark(pattern.c_str(), &bench_formatter, pattern)->Iterations(2500000);
     }
 }
 
@@ -73,7 +73,7 @@ int main(int argc, char *argv[])
     }
     else
     {
-        benchmark::RegisterBenchmark(pattern.c_str(), bench_formatter, pattern);
+        benchmark::RegisterBenchmark(pattern.c_str(), &bench_formatter, pattern);
     }
     benchmark::Initialize(&argc, argv);
     benchmark::RunSpecifiedBenchmarks();

bench/latency.cpp

@@ -39,6 +39,16 @@ void bench_logger(benchmark::State &state, std::shared_ptr<spdlog::logger> logge
     }
 }
 
+void bench_logger_fmt_string(benchmark::State &state, std::shared_ptr<spdlog::logger> logger)
+{
+    int i = 0;
+    for (auto _ : state)
+    {
+        logger->info(FMT_STRING("Hello logger: msg number {}..............."), ++i);
+        ;
+    }
+}
+
 void bench_disabled_macro(benchmark::State &state, std::shared_ptr<spdlog::logger> logger)
 {
     int i = 0;
@@ -88,6 +98,7 @@ int main(int argc, char *argv[])
     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_fmt_string", bench_logger_fmt_string, null_logger_st);
     // with backtrace of 64
     auto tracing_null_logger_st = std::make_shared<spdlog::logger>("bench", std::make_shared<null_sink_st>());
     tracing_null_logger_st->enable_backtrace(64);

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/utils.cmake

@@ -59,3 +59,4 @@ function(spdlog_enable_sanitizer target_name)
     target_compile_options(${target_name} PRIVATE -fno-omit-frame-pointer)
     target_link_libraries(${target_name} PRIVATE -fsanitize=address,undefined -fuse-ld=gold)
 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 3.10)
 project(spdlog_examples CXX)
 
 if(NOT TARGET spdlog)

example/example.cpp

@@ -13,6 +13,7 @@ void rotating_example();
 void daily_example();
 void async_example();
 void binary_example();
+void stopwatch_example();
 void trace_example();
 void multi_sink_example();
 void user_defined_example();
@@ -21,7 +22,7 @@ void syslog_example();
 void custom_flags_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
 
 int main(int, char *[])
 {
@@ -71,6 +72,7 @@ int main(int, char *[])
         user_defined_example();
         err_handler_example();
         trace_example();
+        stopwatch_example();
         custom_flags_example();
 
         // Flush all *registered* loggers using a worker thread every 3 seconds.
@@ -192,6 +194,16 @@ 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);
+}
+
 // A logger with multiple sinks (stdout and file) - each with a different format and log level.
 void multi_sink_example()
 {

include/spdlog/async.h

@@ -35,7 +35,7 @@ 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)
+    static std::shared_ptr<async_logger> create(std::string logger_name, SinkArgs &&...args)
     {
         auto &registry_inst = details::registry::instance();
 
@@ -61,13 +61,13 @@ 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)
+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)
+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)...);
 }

include/spdlog/cfg/argv.h

@@ -21,7 +21,7 @@ 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++)
@@ -30,13 +30,12 @@ void load_argv_levels(int argc, const char **argv)
         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));
 }

include/spdlog/cfg/env.h

@@ -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:
@@ -25,11 +25,13 @@
 
 namespace spdlog {
 namespace cfg {
-void load_env_levels()
+inline 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));
+    if (!env_val.empty())
+    {
+        helpers::load_levels(env_val);
+    }
 }
 
 } // namespace cfg

include/spdlog/cfg/helpers-inl.h

@@ -11,6 +11,7 @@
 #include <spdlog/details/os.h>
 #include <spdlog/details/registry.h>
 
+#include <algorithm>
 #include <string>
 #include <utility>
 #include <sstream>
@@ -78,24 +79,40 @@ 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)
+SPDLOG_INLINE void load_levels(const std::string &input)
 {
+    if (input.empty() || input.size() > 512)
+    {
+        return;
+    }
+
     auto key_vals = extract_key_vals_(input);
-    log_levels rv;
+    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)
     {
         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
+        // ignore unrecognized level names
         if (level == level::off && level_name != "off")
         {
-            level = level::info;
+            continue;
+        }
+        if (logger_name.empty()) // no logger name indicate global level
+        {
+            global_level_found = true;
+            global_level = level;
+        }
+        else
+        {
+            levels[logger_name] = level;
         }
-        rv.set(logger_name, level);
     }
-    return rv;
+
+    details::registry::instance().set_levels(std::move(levels), global_level_found ? &global_level : nullptr);
 }
 
 } // namespace helpers

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 {
@@ -17,7 +18,7 @@ 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);
+SPDLOG_API void load_levels(const std::string &txt);
 } // namespace helpers
 
 } // namespace cfg

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

@@ -9,15 +9,21 @@
 
 namespace spdlog {
 namespace level {
+
 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 void set_string_view(spdlog::level::level_enum l, const string_view_t &s) SPDLOG_NOEXCEPT
+{
+    level_string_views[l] = s;
+}
+
 SPDLOG_INLINE const char *to_short_c_str(spdlog::level::level_enum l) SPDLOG_NOEXCEPT
 {
     return short_level_names[l];

include/spdlog/common.h

@@ -88,7 +88,9 @@ 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
@@ -101,6 +103,7 @@ using err_handler = std::function<void(const std::string &err_msg)>;
 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>;
+using wmemory_buf_t = fmt::basic_memory_buffer<wchar_t, 250>;
 
 #ifdef SPDLOG_WCHAR_TO_UTF8_SUPPORT
 #ifndef _WIN32
@@ -163,11 +166,11 @@ enum level_enum
     }
 #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 void set_string_view(spdlog::level::level_enum l, const string_view_t &s) 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
 
 //
@@ -204,8 +207,8 @@ 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
 {
@@ -232,7 +235,7 @@ namespace details {
 using std::make_unique;
 #else
 template<typename T, typename... Args>
-std::unique_ptr<T> make_unique(Args &&... 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)...));

include/spdlog/details/file_helper-inl.h

@@ -29,12 +29,27 @@ 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");
+
+    auto *mode = SPDLOG_FILENAME_T("ab");
+    auto *trunc_mode = SPDLOG_FILENAME_T("wb");
 
     for (int tries = 0; tries < open_tries_; ++tries)
     {
         // create containing folder if not exists already.
         os::create_dir(os::dir_name(fname));
+        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))
         {
             return;
@@ -118,7 +133,7 @@ SPDLOG_INLINE std::tuple<filename_t, filename_t> file_helper::split_by_extension
     }
 
     // treat cases like "/etc/rc.d/somelogfile or "/abc/.hiddenfile"
-    auto folder_index = fname.rfind(details::os::folder_sep);
+    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());

include/spdlog/details/fmt_helper.h

@@ -34,7 +34,15 @@ 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)));
+    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)));
 }
 
 inline void pad2(int n, memory_buf_t &dest)

include/spdlog/details/log_msg_buffer-inl.h

@@ -26,7 +26,9 @@ SPDLOG_INLINE log_msg_buffer::log_msg_buffer(const log_msg_buffer &other)
     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();
 }

include/spdlog/details/mpmc_blocking_q.h

@@ -110,6 +110,12 @@ public:
         return q_.overrun_counter();
     }
 
+    size_t size()
+    {
+        std::unique_lock<std::mutex> lock(queue_mutex_);
+        return q_.size();
+    }
+
 private:
     std::mutex queue_mutex_;
     std::condition_variable push_cv_;

include/spdlog/details/os-inl.h

@@ -397,17 +397,26 @@ 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 *, 15> terms = {{"ansi", "color", "console", "cygwin", "gnome", "konsole", "kterm", "linux",
+            "msys", "putty", "rxvt", "screen", "vt100", "xterm", "alacritty"}};
+
+        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
 }
@@ -427,7 +436,7 @@ 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)()))
+    if (wstr.size() > static_cast<size_t>((std::numeric_limits<int>::max)()) / 2 - 1)
     {
         throw_spdlog_ex("UTF-16 string is too big to be converted to UTF-8");
     }
@@ -459,6 +468,41 @@ SPDLOG_INLINE void wstr_to_utf8buf(wstring_view_t wstr, memory_buf_t &target)
 
     throw_spdlog_ex(fmt::format("WideCharToMultiByte failed. Last error: {}", ::GetLastError()));
 }
+
+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;
+    }
+
+    int result_size = static_cast<int>(target.capacity());
+    if (str_size + 1 > result_size)
+    {
+        result_size = ::MultiByteToWideChar(CP_UTF8, MB_ERR_INVALID_CHARS, str.data(), str_size, NULL, 0);
+    }
+
+    if (result_size > 0)
+    {
+        target.resize(result_size);
+        result_size = ::MultiByteToWideChar(CP_UTF8, MB_ERR_INVALID_CHARS, str.data(), str_size, target.data(), result_size);
+
+        if (result_size > 0)
+        {
+            target.resize(result_size);
+            return;
+        }
+    }
+
+    throw_spdlog_ex(fmt::format("MultiByteToWideChar failed. Last error: {}", ::GetLastError()));
+}
 #endif // (defined(SPDLOG_WCHAR_TO_UTF8_SUPPORT) || defined(SPDLOG_WCHAR_FILENAMES)) && defined(_WIN32)
 
 // return true on success
@@ -489,15 +533,10 @@ SPDLOG_INLINE bool create_dir(filename_t path)
         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);
+        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)
         {
@@ -523,11 +562,7 @@ SPDLOG_INLINE bool create_dir(filename_t path)
 // "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);
+    auto pos = path.find_last_of(folder_seps_filename);
     return pos != filename_t::npos ? path.substr(0, pos) : filename_t{};
 }
 

include/spdlog/details/os.h

@@ -32,11 +32,16 @@ SPDLOG_API std::tm gmtime() SPDLOG_NOEXCEPT;
 SPDLOG_CONSTEXPR static const char *default_eol = SPDLOG_EOL;
 
 // folder separator
+#if !defined(SPDLOG_FOLDER_SEPS)
 #ifdef _WIN32
-static const char folder_sep = '\\';
+#define SPDLOG_FOLDER_SEPS "\\/"
 #else
-SPDLOG_CONSTEXPR static const char folder_sep = '/';
+#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);
@@ -84,7 +89,9 @@ SPDLOG_API bool is_color_terminal() SPDLOG_NOEXCEPT;
 SPDLOG_API bool in_terminal(FILE *file) SPDLOG_NOEXCEPT;
 
 #if (defined(SPDLOG_WCHAR_TO_UTF8_SUPPORT) || defined(SPDLOG_WCHAR_FILENAMES)) && defined(_WIN32)
-void wstr_to_utf8buf(wstring_view_t wstr, memory_buf_t &target);
+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

include/spdlog/details/registry-inl.h

@@ -67,7 +67,11 @@ SPDLOG_INLINE void registry::initialize_logger(std::shared_ptr<logger> new_logge
         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)
@@ -171,7 +175,7 @@ SPDLOG_INLINE void registry::set_level(level::level_enum log_level)
     {
         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)
@@ -263,14 +267,24 @@ SPDLOG_INLINE void registry::set_automatic_registration(bool automatic_registrat
     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_)
+    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 = l.second;
-        logger->set_level(levels_.get(logger->name()));
+        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);
+        }
     }
 }
 

include/spdlog/details/registry.h

@@ -9,7 +9,6 @@
 // This class is thread safe
 
 #include <spdlog/common.h>
-#include <spdlog/cfg/log_levels.h>
 
 #include <chrono>
 #include <functional>
@@ -28,6 +27,7 @@ class periodic_worker;
 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;
 
@@ -80,7 +80,8 @@ 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();
 
@@ -90,13 +91,15 @@ private:
 
     void throw_if_exists_(const std::string &logger_name);
     void register_logger_(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);
+    void (*err_handler_)(const std::string &msg) = nullptr;
     std::shared_ptr<thread_pool> tp_;
     std::unique_ptr<periodic_worker> periodic_flusher_;
     std::shared_ptr<logger> default_logger_;

include/spdlog/details/synchronous_factory.h

@@ -13,7 +13,7 @@ class logger;
 struct synchronous_factory
 {
     template<typename Sink, typename... SinkArgs>
-    static std::shared_ptr<spdlog::logger> create(std::string logger_name, SinkArgs &&... args)
+    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));

include/spdlog/details/tcp_client-windows.h

@@ -8,8 +8,8 @@
 #include <spdlog/common.h>
 #include <spdlog/details/os.h>
 
-#include <windows.h>
 #include <winsock2.h>
+#include <windows.h>
 #include <ws2tcpip.h>
 #include <stdlib.h>
 #include <stdio.h>

include/spdlog/details/tcp_client.h

@@ -75,7 +75,11 @@ public:
         int last_errno = 0;
         for (auto *rp = addrinfo_result; rp != nullptr; rp = rp->ai_next)
         {
-            int const flags = SOCK_CLOEXEC;
+#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)
             {
@@ -87,12 +91,9 @@ public:
             {
                 break;
             }
-            else
-            {
-                last_errno = errno;
-                ::close(socket_);
-                socket_ = -1;
-            }
+            last_errno = errno;
+            ::close(socket_);
+            socket_ = -1;
         }
         ::freeaddrinfo(addrinfo_result);
         if (socket_ == -1)

include/spdlog/details/thread_pool-inl.h

@@ -68,6 +68,11 @@ size_t SPDLOG_INLINE thread_pool::overrun_counter()
     return q_.overrun_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)

include/spdlog/details/thread_pool.h

@@ -97,6 +97,7 @@ public:
     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();
+    size_t queue_size();
 
 private:
     q_type q_;

include/spdlog/fmt/bin_to_hex.h

@@ -9,7 +9,7 @@
 
 //
 // Support for logging binary data as hex
-// format flags:
+// format flags, any combination of the followng:
 // {:X} - print in uppercase.
 // {:s} - don't separate each byte with space.
 // {:p} - don't print the position on each line start.
@@ -92,7 +92,7 @@ struct formatter<spdlog::details::dump_info<T>>
     auto parse(ParseContext &ctx) -> decltype(ctx.begin())
     {
         auto it = ctx.begin();
-        while (*it && *it != '}')
+        while (it != ctx.end() && *it != '}')
         {
             switch (*it)
             {

include/spdlog/fmt/bundled/chrono.h

@@ -48,7 +48,7 @@ FMT_CONSTEXPR To lossless_integral_conversion(const From from, int& ec) {
     // From fits in To without any problem.
   } else {
     // From does not always fit in To, resort to a dynamic check.
-    if (from < T::min() || from > T::max()) {
+    if (from < (T::min)() || from > (T::max)()) {
       // outside range.
       ec = 1;
       return {};
@@ -72,43 +72,27 @@ FMT_CONSTEXPR To lossless_integral_conversion(const From from, int& ec) {
   static_assert(F::is_integer, "From must be integral");
   static_assert(T::is_integer, "To must be integral");
 
-  if (F::is_signed && !T::is_signed) {
+  if (detail::const_check(F::is_signed && !T::is_signed)) {
     // From may be negative, not allowed!
-    if (fmt::internal::is_negative(from)) {
+    if (fmt::detail::is_negative(from)) {
       ec = 1;
       return {};
     }
-
     // From is positive. Can it always fit in To?
-    if (F::digits <= T::digits) {
-      // yes, From always fits in To.
-    } else {
-      // from may not fit in To, we have to do a dynamic check
-      if (from > static_cast<From>(T::max())) {
-        ec = 1;
-        return {};
-      }
+    if (F::digits > T::digits &&
+        from > static_cast<From>(detail::max_value<To>())) {
+      ec = 1;
+      return {};
     }
   }
 
-  if (!F::is_signed && T::is_signed) {
-    // can from be held in To?
-    if (F::digits < T::digits) {
-      // yes, From always fits in To.
-    } else {
-      // from may not fit in To, we have to do a dynamic check
-      if (from > static_cast<From>(T::max())) {
-        // outside range.
-        ec = 1;
-        return {};
-      }
-    }
+  if (!F::is_signed && T::is_signed && F::digits >= T::digits &&
+      from > static_cast<From>(detail::max_value<To>())) {
+    ec = 1;
+    return {};
   }
-
-  // reaching here means all is ok for lossless conversion.
-  return static_cast<To>(from);
-
-}  // function
+  return static_cast<To>(from);  // Lossless conversion.
+}
 
 template <typename To, typename From,
           FMT_ENABLE_IF(std::is_same<From, To>::value)>
@@ -141,7 +125,7 @@ FMT_CONSTEXPR To safe_float_conversion(const From from, int& ec) {
 
   // catch the only happy case
   if (std::isfinite(from)) {
-    if (from >= T::lowest() && from <= T::max()) {
+    if (from >= T::lowest() && from <= (T::max)()) {
       return static_cast<To>(from);
     }
     // not within range.
@@ -190,17 +174,16 @@ To safe_duration_cast(std::chrono::duration<FromRep, FromPeriod> from,
   // safe conversion to IntermediateRep
   IntermediateRep count =
       lossless_integral_conversion<IntermediateRep>(from.count(), ec);
-  if (ec) {
-    return {};
-  }
+  if (ec) return {};
   // multiply with Factor::num without overflow or underflow
-  if (Factor::num != 1) {
-    const auto max1 = internal::max_value<IntermediateRep>() / Factor::num;
+  if (detail::const_check(Factor::num != 1)) {
+    const auto max1 = detail::max_value<IntermediateRep>() / Factor::num;
     if (count > max1) {
       ec = 1;
       return {};
     }
-    const auto min1 = std::numeric_limits<IntermediateRep>::min() / Factor::num;
+    const auto min1 =
+        (std::numeric_limits<IntermediateRep>::min)() / Factor::num;
     if (count < min1) {
       ec = 1;
       return {};
@@ -208,17 +191,9 @@ To safe_duration_cast(std::chrono::duration<FromRep, FromPeriod> from,
     count *= Factor::num;
   }
 
-  // this can't go wrong, right? den>0 is checked earlier.
-  if (Factor::den != 1) {
-    count /= Factor::den;
-  }
-  // convert to the to type, safely
-  using ToRep = typename To::rep;
-  const ToRep tocount = lossless_integral_conversion<ToRep>(count, ec);
-  if (ec) {
-    return {};
-  }
-  return To{tocount};
+  if (detail::const_check(Factor::den != 1)) count /= Factor::den;
+  auto tocount = lossless_integral_conversion<typename To::rep>(count, ec);
+  return ec ? To() : To(tocount);
 }
 
 /**
@@ -269,7 +244,7 @@ To safe_duration_cast(std::chrono::duration<FromRep, FromPeriod> from,
 
   // multiply with Factor::num without overflow or underflow
   if (Factor::num != 1) {
-    constexpr auto max1 = internal::max_value<IntermediateRep>() /
+    constexpr auto max1 = detail::max_value<IntermediateRep>() /
                           static_cast<IntermediateRep>(Factor::num);
     if (count > max1) {
       ec = 1;
@@ -306,12 +281,12 @@ To safe_duration_cast(std::chrono::duration<FromRep, FromPeriod> from,
 // Usage: f FMT_NOMACRO()
 #define FMT_NOMACRO
 
-namespace internal {
+namespace detail {
 inline null<> localtime_r FMT_NOMACRO(...) { return null<>(); }
 inline null<> localtime_s(...) { return null<>(); }
 inline null<> gmtime_r(...) { return null<>(); }
 inline null<> gmtime_s(...) { return null<>(); }
-}  // namespace internal
+}  // namespace detail
 
 // Thread-safe replacement for std::localtime
 inline std::tm localtime(std::time_t time) {
@@ -322,22 +297,22 @@ inline std::tm localtime(std::time_t time) {
     dispatcher(std::time_t t) : time_(t) {}
 
     bool run() {
-      using namespace fmt::internal;
+      using namespace fmt::detail;
       return handle(localtime_r(&time_, &tm_));
     }
 
     bool handle(std::tm* tm) { return tm != nullptr; }
 
-    bool handle(internal::null<>) {
-      using namespace fmt::internal;
+    bool handle(detail::null<>) {
+      using namespace fmt::detail;
       return fallback(localtime_s(&tm_, &time_));
     }
 
     bool fallback(int res) { return res == 0; }
 
 #if !FMT_MSC_VER
-    bool fallback(internal::null<>) {
-      using namespace fmt::internal;
+    bool fallback(detail::null<>) {
+      using namespace fmt::detail;
       std::tm* tm = std::localtime(&time_);
       if (tm) tm_ = *tm;
       return tm != nullptr;
@@ -350,6 +325,11 @@ inline std::tm localtime(std::time_t time) {
   return lt.tm_;
 }
 
+inline std::tm localtime(
+    std::chrono::time_point<std::chrono::system_clock> time_point) {
+  return localtime(std::chrono::system_clock::to_time_t(time_point));
+}
+
 // Thread-safe replacement for std::gmtime
 inline std::tm gmtime(std::time_t time) {
   struct dispatcher {
@@ -359,21 +339,21 @@ inline std::tm gmtime(std::time_t time) {
     dispatcher(std::time_t t) : time_(t) {}
 
     bool run() {
-      using namespace fmt::internal;
+      using namespace fmt::detail;
       return handle(gmtime_r(&time_, &tm_));
     }
 
     bool handle(std::tm* tm) { return tm != nullptr; }
 
-    bool handle(internal::null<>) {
-      using namespace fmt::internal;
+    bool handle(detail::null<>) {
+      using namespace fmt::detail;
       return fallback(gmtime_s(&tm_, &time_));
     }
 
     bool fallback(int res) { return res == 0; }
 
 #if !FMT_MSC_VER
-    bool fallback(internal::null<>) {
+    bool fallback(detail::null<>) {
       std::tm* tm = std::gmtime(&time_);
       if (tm) tm_ = *tm;
       return tm != nullptr;
@@ -386,17 +366,33 @@ inline std::tm gmtime(std::time_t time) {
   return gt.tm_;
 }
 
-namespace internal {
-inline std::size_t strftime(char* str, std::size_t count, const char* format,
-                            const std::tm* time) {
+inline std::tm gmtime(
+    std::chrono::time_point<std::chrono::system_clock> time_point) {
+  return gmtime(std::chrono::system_clock::to_time_t(time_point));
+}
+
+namespace detail {
+inline size_t strftime(char* str, size_t count, const char* format,
+                       const std::tm* time) {
   return std::strftime(str, count, format, time);
 }
 
-inline std::size_t strftime(wchar_t* str, std::size_t count,
-                            const wchar_t* format, const std::tm* time) {
+inline size_t strftime(wchar_t* str, size_t count, const wchar_t* format,
+                       const std::tm* time) {
   return std::wcsftime(str, count, format, time);
 }
-}  // namespace internal
+}  // namespace detail
+
+template <typename Char>
+struct formatter<std::chrono::time_point<std::chrono::system_clock>, Char>
+    : formatter<std::tm, Char> {
+  template <typename FormatContext>
+  auto format(std::chrono::time_point<std::chrono::system_clock> val,
+              FormatContext& ctx) -> decltype(ctx.out()) {
+    std::tm time = localtime(val);
+    return formatter<std::tm, Char>::format(time, ctx);
+  }
+};
 
 template <typename Char> struct formatter<std::tm, Char> {
   template <typename ParseContext>
@@ -405,7 +401,7 @@ template <typename Char> struct formatter<std::tm, Char> {
     if (it != ctx.end() && *it == ':') ++it;
     auto end = it;
     while (end != ctx.end() && *end != '}') ++end;
-    tm_format.reserve(internal::to_unsigned(end - it + 1));
+    tm_format.reserve(detail::to_unsigned(end - it + 1));
     tm_format.append(it, end);
     tm_format.push_back('\0');
     return end;
@@ -414,11 +410,10 @@ template <typename Char> struct formatter<std::tm, Char> {
   template <typename FormatContext>
   auto format(const std::tm& tm, FormatContext& ctx) -> decltype(ctx.out()) {
     basic_memory_buffer<Char> buf;
-    std::size_t start = buf.size();
+    size_t start = buf.size();
     for (;;) {
-      std::size_t size = buf.capacity() - start;
-      std::size_t count =
-          internal::strftime(&buf[start], size, &tm_format[0], &tm);
+      size_t size = buf.capacity() - start;
+      size_t count = detail::strftime(&buf[start], size, &tm_format[0], &tm);
       if (count != 0) {
         buf.resize(start + count);
         break;
@@ -430,7 +425,7 @@ template <typename Char> struct formatter<std::tm, Char> {
         // https://github.com/fmtlib/fmt/issues/367
         break;
       }
-      const std::size_t MIN_GROWTH = 10;
+      const size_t MIN_GROWTH = 10;
       buf.reserve(buf.capacity() + (size > MIN_GROWTH ? size : MIN_GROWTH));
     }
     return std::copy(buf.begin(), buf.end(), ctx.out());
@@ -439,7 +434,7 @@ template <typename Char> struct formatter<std::tm, Char> {
   basic_memory_buffer<Char> tm_format;
 };
 
-namespace internal {
+namespace detail {
 template <typename Period> FMT_CONSTEXPR const char* get_units() {
   return nullptr;
 }
@@ -768,19 +763,25 @@ OutputIt format_duration_value(OutputIt out, Rep val, int precision) {
   return format_to(out, std::is_floating_point<Rep>::value ? fp_f : format,
                    val);
 }
+template <typename Char, typename OutputIt>
+OutputIt copy_unit(string_view unit, OutputIt out, Char) {
+  return std::copy(unit.begin(), unit.end(), out);
+}
+
+template <typename OutputIt>
+OutputIt copy_unit(string_view unit, OutputIt out, wchar_t) {
+  // This works when wchar_t is UTF-32 because units only contain characters
+  // that have the same representation in UTF-16 and UTF-32.
+  utf8_to_utf16 u(unit);
+  return std::copy(u.c_str(), u.c_str() + u.size(), out);
+}
 
 template <typename Char, typename Period, typename OutputIt>
 OutputIt format_duration_unit(OutputIt out) {
-  if (const char* unit = get_units<Period>()) {
-    string_view s(unit);
-    if (const_check(std::is_same<Char, wchar_t>())) {
-      utf8_to_utf16 u(s);
-      return std::copy(u.c_str(), u.c_str() + u.size(), out);
-    }
-    return std::copy(s.begin(), s.end(), out);
-  }
+  if (const char* unit = get_units<Period>())
+    return copy_unit(string_view(unit), out, Char());
   const Char num_f[] = {'[', '{', '}', ']', 's', 0};
-  if (Period::den == 1) return format_to(out, num_f, Period::num);
+  if (const_check(Period::den == 1)) return format_to(out, num_f, Period::num);
   const Char num_def_f[] = {'[', '{', '}', '/', '{', '}', ']', 's', 0};
   return format_to(out, num_def_f, Period::num, Period::den);
 }
@@ -874,9 +875,9 @@ struct chrono_formatter {
     if (isnan(value)) return write_nan();
     uint32_or_64_or_128_t<int> n =
         to_unsigned(to_nonnegative_int(value, max_value<int>()));
-    int num_digits = internal::count_digits(n);
+    int num_digits = detail::count_digits(n);
     if (width > num_digits) out = std::fill_n(out, width - num_digits, '0');
-    out = format_decimal<char_type>(out, n, num_digits);
+    out = format_decimal<char_type>(out, n, num_digits).end;
   }
 
   void write_nan() { std::copy_n("nan", 3, out); }
@@ -1004,14 +1005,14 @@ struct chrono_formatter {
     out = format_duration_unit<char_type, Period>(out);
   }
 };
-}  // namespace internal
+}  // namespace detail
 
 template <typename Rep, typename Period, typename Char>
 struct formatter<std::chrono::duration<Rep, Period>, Char> {
  private:
   basic_format_specs<Char> specs;
   int precision;
-  using arg_ref_type = internal::arg_ref<Char>;
+  using arg_ref_type = detail::arg_ref<Char>;
   arg_ref_type width_ref;
   arg_ref_type precision_ref;
   mutable basic_string_view<Char> format_str;
@@ -1032,7 +1033,7 @@ struct formatter<std::chrono::duration<Rep, Period>, Char> {
       return arg_ref_type(arg_id);
     }
 
-    FMT_CONSTEXPR arg_ref_type make_arg_ref(internal::auto_id) {
+    FMT_CONSTEXPR arg_ref_type make_arg_ref(detail::auto_id) {
       return arg_ref_type(context.next_arg_id());
     }
 
@@ -1062,17 +1063,17 @@ struct formatter<std::chrono::duration<Rep, Period>, Char> {
     auto begin = ctx.begin(), end = ctx.end();
     if (begin == end || *begin == '}') return {begin, begin};
     spec_handler handler{*this, ctx, format_str};
-    begin = internal::parse_align(begin, end, handler);
+    begin = detail::parse_align(begin, end, handler);
     if (begin == end) return {begin, begin};
-    begin = internal::parse_width(begin, end, handler);
+    begin = detail::parse_width(begin, end, handler);
     if (begin == end) return {begin, begin};
     if (*begin == '.') {
       if (std::is_floating_point<Rep>::value)
-        begin = internal::parse_precision(begin, end, handler);
+        begin = detail::parse_precision(begin, end, handler);
       else
         handler.on_error("precision not allowed for this argument type");
     }
-    end = parse_chrono_format(begin, end, internal::chrono_format_checker());
+    end = parse_chrono_format(begin, end, detail::chrono_format_checker());
     return {begin, end};
   }
 
@@ -1083,7 +1084,7 @@ struct formatter<std::chrono::duration<Rep, Period>, Char> {
       -> decltype(ctx.begin()) {
     auto range = do_parse(ctx);
     format_str = basic_string_view<Char>(
-        &*range.begin, internal::to_unsigned(range.end - range.begin));
+        &*range.begin, detail::to_unsigned(range.end - range.begin));
     return range.end;
   }
 
@@ -1094,23 +1095,21 @@ struct formatter<std::chrono::duration<Rep, Period>, Char> {
     // is not specified.
     basic_memory_buffer<Char> buf;
     auto out = std::back_inserter(buf);
-    using range = internal::output_range<decltype(ctx.out()), Char>;
-    internal::basic_writer<range> w(range(ctx.out()));
-    internal::handle_dynamic_spec<internal::width_checker>(specs.width,
-                                                           width_ref, ctx);
-    internal::handle_dynamic_spec<internal::precision_checker>(
-        precision, precision_ref, ctx);
+    detail::handle_dynamic_spec<detail::width_checker>(specs.width, width_ref,
+                                                       ctx);
+    detail::handle_dynamic_spec<detail::precision_checker>(precision,
+                                                           precision_ref, ctx);
     if (begin == end || *begin == '}') {
-      out = internal::format_duration_value<Char>(out, d.count(), precision);
-      internal::format_duration_unit<Char, Period>(out);
+      out = detail::format_duration_value<Char>(out, d.count(), precision);
+      detail::format_duration_unit<Char, Period>(out);
     } else {
-      internal::chrono_formatter<FormatContext, decltype(out), Rep, Period> f(
+      detail::chrono_formatter<FormatContext, decltype(out), Rep, Period> f(
           ctx, out, d);
       f.precision = precision;
       parse_chrono_format(begin, end, f);
     }
-    w.write(buf.data(), buf.size(), specs);
-    return w.out();
+    return detail::write(
+        ctx.out(), basic_string_view<Char>(buf.data(), buf.size()), specs);
   }
 };
 

include/spdlog/fmt/bundled/color.h

@@ -198,7 +198,7 @@ struct rgb {
   uint8_t b;
 };
 
-namespace internal {
+namespace detail {
 
 // color is a struct of either a rgb color or a terminal color.
 struct color_type {
@@ -221,7 +221,7 @@ struct color_type {
     uint32_t rgb_color;
   } value;
 };
-}  // namespace internal
+}  // namespace detail
 
 // Experimental text formatting support.
 class text_style {
@@ -298,11 +298,11 @@ class text_style {
   FMT_CONSTEXPR bool has_emphasis() const FMT_NOEXCEPT {
     return static_cast<uint8_t>(ems) != 0;
   }
-  FMT_CONSTEXPR internal::color_type get_foreground() const FMT_NOEXCEPT {
+  FMT_CONSTEXPR detail::color_type get_foreground() const FMT_NOEXCEPT {
     FMT_ASSERT(has_foreground(), "no foreground specified for this style");
     return foreground_color;
   }
-  FMT_CONSTEXPR internal::color_type get_background() const FMT_NOEXCEPT {
+  FMT_CONSTEXPR detail::color_type get_background() const FMT_NOEXCEPT {
     FMT_ASSERT(has_background(), "no background specified for this style");
     return background_color;
   }
@@ -313,7 +313,7 @@ class text_style {
 
  private:
   FMT_CONSTEXPR text_style(bool is_foreground,
-                           internal::color_type text_color) FMT_NOEXCEPT
+                           detail::color_type text_color) FMT_NOEXCEPT
       : set_foreground_color(),
         set_background_color(),
         ems() {
@@ -326,23 +326,23 @@ class text_style {
     }
   }
 
-  friend FMT_CONSTEXPR_DECL text_style fg(internal::color_type foreground)
+  friend FMT_CONSTEXPR_DECL text_style fg(detail::color_type foreground)
       FMT_NOEXCEPT;
-  friend FMT_CONSTEXPR_DECL text_style bg(internal::color_type background)
+  friend FMT_CONSTEXPR_DECL text_style bg(detail::color_type background)
       FMT_NOEXCEPT;
 
-  internal::color_type foreground_color;
-  internal::color_type background_color;
+  detail::color_type foreground_color;
+  detail::color_type background_color;
   bool set_foreground_color;
   bool set_background_color;
   emphasis ems;
 };
 
-FMT_CONSTEXPR text_style fg(internal::color_type foreground) FMT_NOEXCEPT {
+FMT_CONSTEXPR text_style fg(detail::color_type foreground) FMT_NOEXCEPT {
   return text_style(/*is_foreground=*/true, foreground);
 }
 
-FMT_CONSTEXPR text_style bg(internal::color_type background) FMT_NOEXCEPT {
+FMT_CONSTEXPR text_style bg(detail::color_type background) FMT_NOEXCEPT {
   return text_style(/*is_foreground=*/false, background);
 }
 
@@ -350,21 +350,21 @@ FMT_CONSTEXPR text_style operator|(emphasis lhs, emphasis rhs) FMT_NOEXCEPT {
   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,
+  FMT_CONSTEXPR ansi_color_escape(detail::color_type text_color,
                                   const char* esc) FMT_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;
+      bool is_background = esc == detail::data::background_color;
       uint32_t value = text_color.value.term_color;
       // 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>('[');
 
@@ -398,7 +398,7 @@ template <typename Char> struct ansi_color_escape {
     if (em_bits & static_cast<uint8_t>(emphasis::strikethrough))
       em_codes[3] = 9;
 
-    std::size_t index = 0;
+    size_t index = 0;
     for (int i = 0; i < 4; ++i) {
       if (!em_codes[i]) continue;
       buffer[index++] = static_cast<Char>('\x1b');
@@ -429,14 +429,14 @@ template <typename Char> struct ansi_color_escape {
 
 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);
+    detail::color_type foreground) FMT_NOEXCEPT {
+  return ansi_color_escape<Char>(foreground, detail::data::foreground_color);
 }
 
 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);
+    detail::color_type background) FMT_NOEXCEPT {
+  return ansi_color_escape<Char>(background, detail::data::background_color);
 }
 
 template <typename Char>
@@ -455,71 +455,71 @@ inline void fputs<wchar_t>(const wchar_t* chars, FILE* stream) FMT_NOEXCEPT {
 }
 
 template <typename Char> inline void reset_color(FILE* stream) FMT_NOEXCEPT {
-  fputs(internal::data::reset_color, stream);
+  fputs(detail::data::reset_color, stream);
 }
 
 template <> inline void reset_color<wchar_t>(FILE* stream) FMT_NOEXCEPT {
-  fputs(internal::data::wreset_color, stream);
+  fputs(detail::data::wreset_color, stream);
 }
 
 template <typename Char>
-inline void reset_color(basic_memory_buffer<Char>& buffer) FMT_NOEXCEPT {
+inline void reset_color(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,
+void vformat_to(buffer<Char>& buf, const text_style& ts,
                 basic_string_view<Char> format_str,
-                basic_format_args<buffer_context<Char>> args) {
+                basic_format_args<buffer_context<type_identity_t<Char>>> args) {
   bool has_style = false;
   if (ts.has_emphasis()) {
     has_style = true;
-    auto emphasis = internal::make_emphasis<Char>(ts.get_emphasis());
+    auto emphasis = detail::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 = detail::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 = detail::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);
+  detail::vformat_to(buf, format_str, args);
+  if (has_style) detail::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_format_args<buffer_context<type_identity_t<Char>>> args) {
   basic_memory_buffer<Char> buf;
-  internal::vformat_to(buf, ts, to_string_view(format), args);
+  detail::vformat_to(buf, ts, to_string_view(format), args);
   buf.push_back(Char(0));
-  internal::fputs(buf.data(), f);
+  detail::fputs(buf.data(), f);
 }
 
 /**
+  \rst
   Formats a string and prints it to the specified file stream using ANSI
   escape sequences to specify text formatting.
-  Example:
+
+  **Example**::
+
     fmt::print(fmt::emphasis::bold | fg(fmt::color::red),
                "Elapsed time: {0:.2f} seconds", 1.23);
+  \endrst
  */
 template <typename S, typename... Args,
-          FMT_ENABLE_IF(internal::is_string<S>::value)>
+          FMT_ENABLE_IF(detail::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));
+  vprint(f, ts, format_str,
+         fmt::make_args_checked<Args...>(format_str, args...));
 }
 
 /**
@@ -530,7 +530,7 @@ void print(std::FILE* f, const text_style& ts, const S& format_str,
                "Elapsed time: {0:.2f} seconds", 1.23);
  */
 template <typename S, typename... Args,
-          FMT_ENABLE_IF(internal::is_string<S>::value)>
+          FMT_ENABLE_IF(detail::is_string<S>::value)>
 void print(const text_style& ts, const S& format_str, const Args&... args) {
   return print(stdout, ts, format_str, args...);
 }
@@ -540,7 +540,7 @@ 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);
+  detail::vformat_to(buf, ts, to_string_view(format_str), args);
   return fmt::to_string(buf);
 }
 
@@ -560,7 +560,42 @@ 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...));
+                 fmt::make_args_checked<Args...>(format_str, args...));
+}
+
+/**
+  Formats a string with the given text_style and writes the output to ``out``.
+ */
+template <typename OutputIt, typename Char,
+          FMT_ENABLE_IF(detail::is_output_iterator<OutputIt, Char>::value)>
+OutputIt vformat_to(
+    OutputIt out, const text_style& ts, basic_string_view<Char> format_str,
+    basic_format_args<buffer_context<type_identity_t<Char>>> args) {
+  decltype(detail::get_buffer<Char>(out)) buf(detail::get_buffer_init(out));
+  detail::vformat_to(buf, ts, format_str, args);
+  return detail::get_iterator(buf);
+}
+
+/**
+  \rst
+  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);
+  \endrst
+*/
+template <typename OutputIt, typename S, typename... Args,
+          bool enable = detail::is_output_iterator<OutputIt, char_t<S>>::value&&
+              detail::is_string<S>::value>
+inline auto format_to(OutputIt out, const text_style& ts, const S& format_str,
+                      Args&&... args) ->
+    typename std::enable_if<enable, OutputIt>::type {
+  return vformat_to(out, ts, to_string_view(format_str),
+                    fmt::make_args_checked<Args...>(format_str, args...));
 }
 
 FMT_END_NAMESPACE

include/spdlog/fmt/bundled/compile.h

@@ -13,7 +13,33 @@
 #include "format.h"
 
 FMT_BEGIN_NAMESPACE
-namespace internal {
+namespace detail {
+
+// A compile-time string which is compiled into fast formatting code.
+class compiled_string {};
+
+template <typename S>
+struct is_compiled_string : std::is_base_of<compiled_string, S> {};
+
+/**
+  \rst
+  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);
+  \endrst
+ */
+#define FMT_COMPILE(s) FMT_STRING_IMPL(s, fmt::detail::compiled_string)
+
+template <typename T, typename... Tail>
+const T& first(const T& value, const Tail&...) {
+  return value;
+}
 
 // Part of a compiled format string. It can be either literal text or a
 // replacement field.
@@ -62,13 +88,15 @@ template <typename Char> struct part_counter {
     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 int on_arg_id() { return ++num_parts, 0; }
+  FMT_CONSTEXPR int on_arg_id(int) { return ++num_parts, 0; }
+  FMT_CONSTEXPR int on_arg_id(basic_string_view<Char>) {
+    return ++num_parts, 0;
+  }
 
-  FMT_CONSTEXPR void on_replacement_field(const Char*) {}
+  FMT_CONSTEXPR void on_replacement_field(int, const Char*) {}
 
-  FMT_CONSTEXPR const Char* on_format_specs(const Char* begin,
+  FMT_CONSTEXPR const Char* on_format_specs(int, const Char* begin,
                                             const Char* end) {
     // Find the matching brace.
     unsigned brace_counter = 0;
@@ -116,25 +144,28 @@ class format_string_compiler : public error_handler {
       handler_(part::make_text({begin, to_unsigned(end - begin)}));
   }
 
-  FMT_CONSTEXPR void on_arg_id() {
+  FMT_CONSTEXPR int on_arg_id() {
     part_ = part::make_arg_index(parse_context_.next_arg_id());
+    return 0;
   }
 
-  FMT_CONSTEXPR void on_arg_id(int id) {
+  FMT_CONSTEXPR int on_arg_id(int id) {
     parse_context_.check_arg_id(id);
     part_ = part::make_arg_index(id);
+    return 0;
   }
 
-  FMT_CONSTEXPR void on_arg_id(basic_string_view<Char> id) {
+  FMT_CONSTEXPR int on_arg_id(basic_string_view<Char> id) {
     part_ = part::make_arg_name(id);
+    return 0;
   }
 
-  FMT_CONSTEXPR void on_replacement_field(const Char* ptr) {
+  FMT_CONSTEXPR void on_replacement_field(int, const Char* ptr) {
     part_.arg_id_end = ptr;
     handler_(part_);
   }
 
-  FMT_CONSTEXPR const Char* on_format_specs(const Char* begin,
+  FMT_CONSTEXPR const Char* on_format_specs(int, const Char* begin,
                                             const Char* end) {
     auto repl = typename part::replacement();
     dynamic_specs_handler<basic_format_parse_context<Char>> handler(
@@ -160,23 +191,24 @@ FMT_CONSTEXPR void compile_format_string(basic_string_view<Char> format_str,
       format_string_compiler<Char, PartHandler>(format_str, handler));
 }
 
-template <typename Range, typename Context, typename Id>
+template <typename OutputIt, typename Context, typename Id>
 void format_arg(
-    basic_format_parse_context<typename Range::value_type>& parse_ctx,
+    basic_format_parse_context<typename Context::char_type>& parse_ctx,
     Context& ctx, Id arg_id) {
-  ctx.advance_to(
-      visit_format_arg(arg_formatter<Range>(ctx, &parse_ctx), ctx.arg(arg_id)));
+  ctx.advance_to(visit_format_arg(
+      arg_formatter<OutputIt, typename Context::char_type>(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 {
+template <typename Context, typename OutputIt, typename CompiledFormat>
+auto vformat_to(OutputIt 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);
+  Context ctx(out, args);
 
   const auto& parts = cf.parts();
   for (auto part_it = std::begin(parts); part_it != std::end(parts);
@@ -197,12 +229,12 @@ auto vformat_to(Range out, CompiledFormat& cf, basic_format_args<Context> args)
 
     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);
+      detail::format_arg<OutputIt>(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);
+      detail::format_arg<OutputIt>(parse_ctx, ctx, value.str);
       break;
 
     case format_part_t::kind::replacement: {
@@ -226,7 +258,9 @@ auto vformat_to(Range out, CompiledFormat& cf, basic_format_args<Context> args)
 
       advance_to(parse_ctx, part.arg_id_end);
       ctx.advance_to(
-          visit_format_arg(arg_formatter<Range>(ctx, nullptr, &specs), arg));
+          visit_format_arg(arg_formatter<OutputIt, typename Context::char_type>(
+                               ctx, nullptr, &specs),
+                           arg));
       break;
     }
     }
@@ -240,7 +274,7 @@ 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>>;
+  using parts_container = std::vector<detail::format_part<char_type>>;
 
   parts_container compiled_parts;
 
@@ -305,7 +339,7 @@ struct compiled_format_base<S, enable_if_t<is_compile_string<S>::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()));
+            detail::to_string_view(S()));
     return compiled_parts.data;
   }
 };
@@ -318,8 +352,8 @@ class compiled_format : private compiled_format_base<S> {
  private:
   basic_string_view<char_type> format_str_;
 
-  template <typename Context, typename Range, typename CompiledFormat>
-  friend auto cf::vformat_to(Range out, CompiledFormat& cf,
+  template <typename Context, typename OutputIt, typename CompiledFormat>
+  friend auto cf::vformat_to(OutputIt out, CompiledFormat& cf,
                              basic_format_args<Context> args) ->
       typename Context::iterator;
 
@@ -334,7 +368,8 @@ 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;
@@ -359,8 +394,7 @@ template <typename Char> struct text {
 
   template <typename OutputIt, typename... Args>
   OutputIt format(OutputIt out, const Args&...) const {
-    // TODO: reserve
-    return copy_str<Char>(data.begin(), data.end(), out);
+    return write<Char>(out, data);
   }
 };
 
@@ -373,32 +407,18 @@ 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 Char, typename OutputIt>
-OutputIt format_default(OutputIt out, double value) {
-  writer w(out);
-  w.write(value);
-  return w.out();
-}
+  template <typename OutputIt, typename... Args>
+  OutputIt format(OutputIt out, const Args&...) const {
+    return write<Char>(out, value);
+  }
+};
 
-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 {
@@ -408,13 +428,32 @@ template <typename Char, typename T, int N> struct field {
   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);
+    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 N and has format specifiers.
+template <typename Char, typename T, int N> struct spec_field {
+  using char_type = Char;
+  mutable formatter<T, Char> fmt;
+
+  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...);
+    const auto& vargs =
+        make_format_args<basic_format_context<OutputIt, Char>>(args...);
+    basic_format_context<OutputIt, Char> ctx(out, vargs);
+    return fmt.format(arg, 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;
@@ -450,7 +489,8 @@ constexpr auto compile_format_string(S format_str);
 
 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()) {
+  if constexpr (POS !=
+                basic_string_view<typename S::char_type>(format_str).size()) {
     constexpr auto tail = compile_format_string<Args, POS, ID>(format_str);
     if constexpr (std::is_same<remove_cvref_t<decltype(tail)>,
                                unknown_format>())
@@ -462,6 +502,22 @@ 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;
+};
+
+template <typename T, typename Char>
+constexpr parse_specs_result<T, Char> parse_specs(basic_string_view<Char> str,
+                                                  size_t pos, int arg_id) {
+  str.remove_prefix(pos);
+  auto ctx = basic_format_parse_context<Char>(str, {}, arg_id + 1);
+  auto f = formatter<T, Char>();
+  auto end = f.parse(ctx);
+  return {f, pos + (end - str.data()) + 1, ctx.next_arg_id()};
+}
+
 // 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>
@@ -475,12 +531,13 @@ constexpr auto compile_format_string(S format_str) {
       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 + 1>(field<char_type, type, ID>(),
+                                               format_str);
+    } else if constexpr (str[POS + 1] == ':') {
+      using type = get_type<ID, Args>;
+      constexpr auto result = parse_specs<type>(str, POS + 2, ID);
+      return parse_tail<Args, result.end, result.next_arg_id>(
+          spec_field<char_type, type, ID>{result.fmt}, format_str);
     } else {
       return unknown_format();
     }
@@ -490,104 +547,153 @@ constexpr auto compile_format_string(S format_str) {
     return parse_tail<Args, POS + 2, ID>(make_text(str, POS, 1), format_str);
   } else {
     constexpr auto end = parse_text(str, POS + 1);
-    return parse_tail<Args, end, ID>(make_text(str, POS, end - POS),
-                                     format_str);
+    if constexpr (end - POS > 1) {
+      return parse_tail<Args, end, ID>(make_text(str, POS, end - POS),
+                                       format_str);
+    } else {
+      return parse_tail<Args, end, ID>(code_unit<char_type>{str[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)>
+          FMT_ENABLE_IF(is_compile_string<S>::value ||
+                        detail::is_compiled_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);
+    return detail::make_text(str, 0, 0);
   } else {
     constexpr auto result =
-        internal::compile_format_string<internal::type_list<Args...>, 0, 0>(
+        detail::compile_format_string<detail::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));
+                               detail::unknown_format>()) {
+      return detail::compiled_format<S, Args...>(to_string_view(format_str));
     } else {
       return result;
     }
   }
 }
-
-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);
-}
-
-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) {
-  return cf.format(out, args...);
-}
-#  else
+#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));
+constexpr auto compile(S format_str) -> detail::compiled_format<S, Args...> {
+  return detail::compiled_format<S, Args...>(to_string_view(format_str));
 }
-#  endif  // __cpp_if_constexpr
-#endif    // FMT_USE_CONSTEXPR
+#endif  // __cpp_if_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...>(
+    -> detail::compiled_format<const Char*, Args...> {
+  return detail::compiled_format<const Char*, Args...>(
       basic_string_view<Char>(format_str, N - 1));
 }
+}  // namespace detail
+
+// DEPRECATED! use FMT_COMPILE instead.
+template <typename... Args>
+FMT_DEPRECATED auto compile(const Args&... args)
+    -> decltype(detail::compile(args...)) {
+  return detail::compile(args...);
+}
+
+#if FMT_USE_CONSTEXPR
+#  ifdef __cpp_if_constexpr
 
 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) {
+          FMT_ENABLE_IF(detail::is_compiled_format<CompiledFormat>::value)>
+FMT_INLINE 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...));
+  cf.format(detail::buffer_appender<Char>(buffer), args...);
   return to_string(buffer);
 }
 
 template <typename OutputIt, typename CompiledFormat, typename... Args,
-          FMT_ENABLE_IF(std::is_base_of<internal::basic_compiled_format,
+          FMT_ENABLE_IF(detail::is_compiled_format<CompiledFormat>::value)>
+OutputIt format_to(OutputIt out, const CompiledFormat& cf,
+                   const Args&... args) {
+  return cf.format(out, args...);
+}
+#  endif  // __cpp_if_constexpr
+#endif    // FMT_USE_CONSTEXPR
+
+template <typename CompiledFormat, typename... Args,
+          typename Char = typename CompiledFormat::char_type,
+          FMT_ENABLE_IF(std::is_base_of<detail::basic_compiled_format,
+                                        CompiledFormat>::value)>
+std::basic_string<Char> format(const CompiledFormat& cf, const Args&... args) {
+  basic_memory_buffer<Char> buffer;
+  using context = buffer_context<Char>;
+  detail::cf::vformat_to<context>(detail::buffer_appender<Char>(buffer), cf,
+                                  make_format_args<context>(args...));
+  return to_string(buffer);
+}
+
+template <typename S, typename... Args,
+          FMT_ENABLE_IF(detail::is_compiled_string<S>::value)>
+FMT_INLINE std::basic_string<typename S::char_type> format(const S&,
+                                                           Args&&... args) {
+#ifdef __cpp_if_constexpr
+  if constexpr (std::is_same<typename S::char_type, char>::value) {
+    constexpr basic_string_view<typename S::char_type> str = S();
+    if (str.size() == 2 && str[0] == '{' && str[1] == '}')
+      return fmt::to_string(detail::first(args...));
+  }
+#endif
+  constexpr auto compiled = detail::compile<Args...>(S());
+  return format(compiled, std::forward<Args>(args)...);
+}
+
+template <typename OutputIt, typename CompiledFormat, typename... Args,
+          FMT_ENABLE_IF(std::is_base_of<detail::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...));
+  return detail::cf::vformat_to<context>(out, cf,
+                                         make_format_args<context>(args...));
 }
 
-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) {
+template <typename OutputIt, typename S, typename... Args,
+          FMT_ENABLE_IF(detail::is_compiled_string<S>::value)>
+OutputIt format_to(OutputIt out, const S&, const Args&... args) {
+  constexpr auto compiled = detail::compile<Args...>(S());
+  return format_to(out, compiled, args...);
+}
+
+template <typename OutputIt, typename CompiledFormat, typename... Args>
+auto format_to_n(OutputIt out, size_t n, const CompiledFormat& cf,
+                 const Args&... args) ->
+    typename std::enable_if<
+        detail::is_output_iterator<OutputIt,
+                                   typename CompiledFormat::char_type>::value &&
+            std::is_base_of<detail::basic_compiled_format,
+                            CompiledFormat>::value,
+        format_to_n_result<OutputIt>>::type {
   auto it =
-      format_to(internal::truncating_iterator<OutputIt>(out, n), cf, args...);
+      format_to(detail::truncating_iterator<OutputIt>(out, n), cf, args...);
+  return {it.base(), it.count()};
+}
+
+template <typename OutputIt, typename S, typename... Args,
+          FMT_ENABLE_IF(detail::is_compiled_string<S>::value)>
+format_to_n_result<OutputIt> format_to_n(OutputIt out, size_t n, const S&,
+                                         const Args&... args) {
+  constexpr auto compiled = detail::compile<Args...>(S());
+  auto it = format_to(detail::truncating_iterator<OutputIt>(out, n), compiled,
+                      args...);
   return {it.base(), it.count()};
 }
 
 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();
+size_t formatted_size(const CompiledFormat& cf, const Args&... args) {
+  return format_to(detail::counting_iterator(), cf, args...).count();
 }
 
 FMT_END_NAMESPACE

include/spdlog/fmt/bundled/locale.h

@@ -14,63 +14,49 @@
 
 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));
-}
-
+namespace detail {
 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);
+  detail::vformat_to(buffer, format_str, args, detail::locale_ref(loc));
   return fmt::to_string(buffer);
 }
-}  // namespace internal
+}  // namespace detail
 
 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);
+  return detail::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...));
+  return detail::vformat(loc, to_string_view(format_str),
+                         fmt::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>>>
+          typename Char = char_t<S>,
+          FMT_ENABLE_IF(detail::is_output_iterator<OutputIt, Char>::value)>
 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));
+    basic_format_args<buffer_context<type_identity_t<Char>>> args) {
+  decltype(detail::get_buffer<Char>(out)) buf(detail::get_buffer_init(out));
+  vformat_to(buf, to_string_view(format_str), args, detail::locale_ref(loc));
+  return detail::get_iterator(buf);
 }
 
 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));
+          bool enable = detail::is_output_iterator<OutputIt, char_t<S>>::value>
+inline auto format_to(OutputIt out, const std::locale& loc,
+                      const S& format_str, Args&&... args) ->
+    typename std::enable_if<enable, OutputIt>::type {
+  const auto& vargs = fmt::make_args_checked<Args...>(format_str, args...);
+  return vformat_to(out, loc, to_string_view(format_str), vargs);
 }
 
 FMT_END_NAMESPACE

include/spdlog/fmt/bundled/os.h

@@ -0,0 +1,480 @@
+// 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_
+
+#if defined(__MINGW32__) || defined(__CYGWIN__)
+// Workaround MinGW bug https://sourceforge.net/p/mingw/bugs/2024/.
+#  undef __STRICT_ANSI__
+#endif
+
+#include <cerrno>
+#include <clocale>  // for locale_t
+#include <cstddef>
+#include <cstdio>
+#include <cstdlib>  // for strtod_l
+
+#if defined __APPLE__ || defined(__FreeBSD__)
+#  include <xlocale.h>  // for LC_NUMERIC_MASK on OS X
+#endif
+
+#include "format.h"
+
+// 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
+
+#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_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
+
+/**
+  \rst
+  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 to allow passing
+  different types of strings to a function, for example::
+
+    template <typename... Args>
+    std::string format(cstring_view format_str, const Args & ... args);
+
+    format("{}", 42);
+    format(std::string("{}"), 42);
+  \endrst
+ */
+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) {}
+
+  /**
+    \rst
+    Constructs a string reference from an ``std::string`` object.
+    \endrst
+   */
+  basic_cstring_view(const std::basic_string<Char>& s) : data_(s.c_str()) {}
+
+  /** Returns the pointer to a C string. */
+  const Char* c_str() const { return data_; }
+};
+
+using cstring_view = basic_cstring_view<char>;
+using wcstring_view = basic_cstring_view<wchar_t>;
+
+// An error code.
+class error_code {
+ private:
+  int value_;
+
+ public:
+  explicit error_code(int value = 0) FMT_NOEXCEPT : value_(value) {}
+
+  int get() const FMT_NOEXCEPT { return value_; }
+};
+
+#ifdef _WIN32
+namespace detail {
+// A converter from UTF-16 to UTF-8.
+// It is only provided for Windows since other systems support UTF-8 natively.
+class utf16_to_utf8 {
+ private:
+  memory_buffer buffer_;
+
+ public:
+  utf16_to_utf8() {}
+  FMT_API explicit utf16_to_utf8(wstring_view s);
+  operator string_view() const { return string_view(&buffer_[0], size()); }
+  size_t size() const { return buffer_.size() - 1; }
+  const char* c_str() const { return &buffer_[0]; }
+  std::string str() const { return std::string(&buffer_[0], size()); }
+
+  // Performs conversion returning a system error code instead of
+  // throwing exception on conversion error. This method may still throw
+  // in case of memory allocation error.
+  FMT_API int convert(wstring_view s);
+};
+
+FMT_API void format_windows_error(buffer<char>& out, int error_code,
+                                  string_view message) FMT_NOEXCEPT;
+}  // namespace detail
+
+/** A Windows error. */
+class windows_error : public system_error {
+ private:
+  FMT_API void init(int error_code, string_view format_str, format_args args);
+
+ public:
+  /**
+   \rst
+   Constructs a :class:`fmt::windows_error` object with the description
+   of the form
+
+   .. parsed-literal::
+     *<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 windows_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);
+     }
+   \endrst
+  */
+  template <typename... Args>
+  windows_error(int error_code, string_view message, const Args&... args) {
+    init(error_code, message, make_format_args(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,
+                                  string_view message) FMT_NOEXCEPT;
+#endif  // _WIN32
+
+// A buffered file.
+class buffered_file {
+ private:
+  FILE* file_;
+
+  friend class file;
+
+  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.
+  buffered_file() FMT_NOEXCEPT : file_(nullptr) {}
+
+  // Destroys the object closing the file it represents if any.
+  FMT_API ~buffered_file() FMT_NOEXCEPT;
+
+ public:
+  buffered_file(buffered_file&& other) FMT_NOEXCEPT : file_(other.file_) {
+    other.file_ = nullptr;
+  }
+
+  buffered_file& operator=(buffered_file&& other) {
+    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.
+  FILE* get() const FMT_NOEXCEPT { return file_; }
+
+  // We place parentheses around fileno to workaround a bug in some versions
+  // of MinGW that define fileno as a macro.
+  FMT_API int(fileno)() const;
+
+  void vprint(string_view format_str, format_args args) {
+    fmt::vprint(file_, format_str, args);
+  }
+
+  template <typename... Args>
+  inline void print(string_view format_str, const Args&... args) {
+    vprint(format_str, make_format_args(args...));
+  }
+};
+
+#if FMT_USE_FCNTL
+// A file. Closed file is represented by a file object with descriptor -1.
+// Methods that are not declared with FMT_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 file {
+ private:
+  int fd_;  // File descriptor.
+
+  // Constructs a file object with a given descriptor.
+  explicit file(int fd) : fd_(fd) {}
+
+ 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.
+  };
+
+  // Constructs a file object which doesn't represent any file.
+  file() FMT_NOEXCEPT : fd_(-1) {}
+
+  // Opens a file and constructs a file object representing this file.
+  FMT_API file(cstring_view path, int oflag);
+
+ public:
+  file(const file&) = delete;
+  void operator=(const file&) = delete;
+
+  file(file&& other) FMT_NOEXCEPT : fd_(other.fd_) { other.fd_ = -1; }
+
+  file& operator=(file&& other) FMT_NOEXCEPT {
+    close();
+    fd_ = other.fd_;
+    other.fd_ = -1;
+    return *this;
+  }
+
+  // Destroys the object closing the file it represents if any.
+  FMT_API ~file() FMT_NOEXCEPT;
+
+  // Returns the file descriptor.
+  int descriptor() const FMT_NOEXCEPT { return fd_; }
+
+  // Closes the file.
+  FMT_API void close();
+
+  // Returns the file size. The size has signed type for consistency with
+  // stat::st_size.
+  FMT_API long long size() const;
+
+  // Attempts to read count bytes from the file into the specified buffer.
+  FMT_API size_t read(void* buffer, size_t count);
+
+  // Attempts to write count bytes from the specified buffer to the file.
+  FMT_API size_t write(const void* buffer, size_t count);
+
+  // Duplicates a file descriptor with the dup function and returns
+  // the duplicate as a file object.
+  FMT_API static file dup(int fd);
+
+  // Makes fd be the copy of this file descriptor, closing fd first if
+  // necessary.
+  FMT_API void dup2(int fd);
+
+  // Makes fd be the copy of this file descriptor, closing fd first if
+  // necessary.
+  FMT_API void dup2(int fd, error_code& ec) FMT_NOEXCEPT;
+
+  // Creates a pipe setting up read_end and write_end file objects for reading
+  // and writing respectively.
+  FMT_API static void pipe(file& read_end, file& write_end);
+
+  // Creates a buffered_file object associated with this file and detaches
+  // this file object from the file.
+  FMT_API buffered_file fdopen(const char* mode);
+};
+
+// Returns the memory page size.
+long getpagesize();
+
+namespace detail {
+
+struct buffer_size {
+  size_t value = 0;
+  buffer_size operator=(size_t val) const {
+    auto bs = buffer_size();
+    bs.value = val;
+    return bs;
+  }
+};
+
+struct ostream_params {
+  int oflag = file::WRONLY | file::CREATE;
+  size_t buffer_size = BUFSIZ > 32768 ? BUFSIZ : 32768;
+
+  ostream_params() {}
+
+  template <typename... T>
+  ostream_params(T... params, int oflag) : ostream_params(params...) {
+    this->oflag = oflag;
+  }
+
+  template <typename... T>
+  ostream_params(T... params, detail::buffer_size bs)
+      : ostream_params(params...) {
+    this->buffer_size = bs.value;
+  }
+};
+}  // namespace detail
+
+static constexpr detail::buffer_size buffer_size;
+
+// A fast output stream which is not thread-safe.
+class ostream final : private detail::buffer<char> {
+ private:
+  file file_;
+
+  void flush() {
+    if (size() == 0) return;
+    file_.write(data(), size());
+    clear();
+  }
+
+  FMT_API void grow(size_t) override final;
+
+  ostream(cstring_view path, const detail::ostream_params& params)
+      : file_(path, params.oflag) {
+    set(new char[params.buffer_size], params.buffer_size);
+  }
+
+ public:
+  ostream(ostream&& other)
+      : detail::buffer<char>(other.data(), other.size(), other.capacity()),
+        file_(std::move(other.file_)) {
+    other.set(nullptr, 0);
+  }
+  ~ostream() {
+    flush();
+    delete[] data();
+  }
+
+  template <typename... T>
+  friend ostream output_file(cstring_view path, T... params);
+
+  void close() {
+    flush();
+    file_.close();
+  }
+
+  template <typename S, typename... Args>
+  void print(const S& format_str, const Args&... args) {
+    format_to(detail::buffer_appender<char>(*this), format_str, args...);
+  }
+};
+
+/**
+  Opens a file for writing. Supported parameters passed in `params`:
+  * ``<integer>``: Output flags (``file::WRONLY | file::CREATE`` by default)
+  * ``buffer_size=<integer>``: Output buffer size
+ */
+template <typename... T>
+inline ostream output_file(cstring_view path, T... params) {
+  return {path, detail::ostream_params(params...)};
+}
+#endif  // FMT_USE_FCNTL
+
+#ifdef FMT_LOCALE
+// A "C" numeric locale.
+class locale {
+ private:
+#  ifdef _WIN32
+  using locale_t = _locale_t;
+
+  static void freelocale(locale_t loc) { _free_locale(loc); }
+
+  static double strtod_l(const char* nptr, char** endptr, _locale_t loc) {
+    return _strtod_l(nptr, endptr, loc);
+  }
+#  endif
+
+  locale_t locale_;
+
+ public:
+  using type = locale_t;
+  locale(const locale&) = delete;
+  void operator=(const locale&) = delete;
+
+  locale() {
+#  ifndef _WIN32
+    locale_ = FMT_SYSTEM(newlocale(LC_NUMERIC_MASK, "C", nullptr));
+#  else
+    locale_ = _create_locale(LC_NUMERIC, "C");
+#  endif
+    if (!locale_) FMT_THROW(system_error(errno, "cannot create locale"));
+  }
+  ~locale() { freelocale(locale_); }
+
+  type get() const { return locale_; }
+
+  // Converts string to floating-point number and advances str past the end
+  // of the parsed input.
+  double strtod(const char*& str) const {
+    char* end = nullptr;
+    double result = strtod_l(str, &end, locale_);
+    str = end;
+    return result;
+  }
+};
+using Locale FMT_DEPRECATED_ALIAS = locale;
+#endif  // FMT_LOCALE
+FMT_END_NAMESPACE
+
+#endif  // FMT_OS_H_

include/spdlog/fmt/bundled/ostream.h

@@ -9,10 +9,15 @@
 #define FMT_OSTREAM_H_
 
 #include <ostream>
+
 #include "format.h"
 
 FMT_BEGIN_NAMESPACE
-namespace internal {
+
+template <typename Char> class basic_printf_parse_context;
+template <typename OutputIt, typename Char> class basic_printf_context;
+
+namespace detail {
 
 template <class Char> class formatbuf : public std::basic_streambuf<Char> {
  private:
@@ -44,17 +49,27 @@ template <class Char> class formatbuf : public std::basic_streambuf<Char> {
   }
 };
 
+struct converter {
+  template <typename T, FMT_ENABLE_IF(is_integral<T>::value)> converter(T);
+};
+
 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);
+  void_t<> operator<<(converter);
 };
 
+// Hide insertion operators for built-in types.
+template <typename Char, typename Traits>
+void_t<> operator<<(std::basic_ostream<Char, Traits>&, Char);
+template <typename Char, typename Traits>
+void_t<> operator<<(std::basic_ostream<Char, Traits>&, char);
+template <typename Traits>
+void_t<> operator<<(std::basic_ostream<char, Traits>&, char);
+template <typename Traits>
+void_t<> operator<<(std::basic_ostream<char, Traits>&, signed char);
+template <typename Traits>
+void_t<> operator<<(std::basic_ostream<char, Traits>&, unsigned char);
+
 // Checks if T has a user-defined operator<< (e.g. not a member of
 // std::ostream).
 template <typename T, typename Char> class is_streamable {
@@ -75,7 +90,7 @@ template <typename T, typename Char> class is_streamable {
 
 // Write the content of buf to os.
 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;
   unsigned_streamsize size = buf.size();
@@ -93,34 +108,53 @@ 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 !defined(FMT_STATIC_THOUSANDS_SEPARATOR)
   if (loc) output.imbue(loc.get<std::locale>());
-  #endif
-  output.exceptions(std::ios_base::failbit | std::ios_base::badbit);
+#endif
   output << value;
-  buf.resize(buf.size());
+  output.exceptions(std::ios_base::failbit | std::ios_base::badbit);
+  buf.try_resize(buf.size());
 }
 
 // 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>>
-    : formatter<basic_string_view<Char>, Char> {
-  template <typename Context>
-  auto format(const T& value, Context& ctx) -> decltype(ctx.out()) {
+    : private formatter<basic_string_view<Char>, Char> {
+  FMT_CONSTEXPR 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 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());
+  }
 };
-}  // namespace internal
+}  // namespace detail
 
 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);
+  detail::vformat_to(buffer, format_str, args);
+  detail::write_buffer(os, buffer);
 }
 
 /**
@@ -133,10 +167,10 @@ void vprint(std::basic_ostream<Char>& os, basic_string_view<Char> format_str,
   \endrst
  */
 template <typename S, typename... Args,
-          typename Char = enable_if_t<internal::is_string<S>::value, char_t<S>>>
+          typename Char = enable_if_t<detail::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::make_args_checked<Args...>(format_str, args...));
 }
 FMT_END_NAMESPACE
 

include/spdlog/fmt/bundled/posix.h

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

include/spdlog/fmt/bundled/printf.h

@@ -14,7 +14,7 @@
 #include "ostream.h"
 
 FMT_BEGIN_NAMESPACE
-namespace internal {
+namespace detail {
 
 // Checks if a value fits in int - used to avoid warnings about comparing
 // signed and unsigned integers.
@@ -90,11 +90,11 @@ template <typename T, typename Context> class arg_converter {
     if (const_check(sizeof(target_type) <= sizeof(int))) {
       // Extra casts are used to silence warnings.
       if (is_signed) {
-        arg_ = internal::make_arg<Context>(
+        arg_ = detail::make_arg<Context>(
             static_cast<int>(static_cast<target_type>(value)));
       } else {
         using unsigned_type = typename make_unsigned_or_bool<target_type>::type;
-        arg_ = internal::make_arg<Context>(
+        arg_ = detail::make_arg<Context>(
             static_cast<unsigned>(static_cast<unsigned_type>(value)));
       }
     } else {
@@ -102,9 +102,9 @@ template <typename T, typename Context> class arg_converter {
         // glibc's printf doesn't sign extend arguments of smaller types:
         //   std::printf("%lld", -42);  // prints "4294967254"
         // but we don't have to do the same because it's a UB.
-        arg_ = internal::make_arg<Context>(static_cast<long long>(value));
+        arg_ = detail::make_arg<Context>(static_cast<long long>(value));
       } else {
-        arg_ = internal::make_arg<Context>(
+        arg_ = detail::make_arg<Context>(
             static_cast<typename make_unsigned_or_bool<U>::type>(value));
       }
     }
@@ -133,7 +133,7 @@ template <typename Context> class char_converter {
 
   template <typename T, FMT_ENABLE_IF(std::is_integral<T>::value)>
   void operator()(T value) {
-    arg_ = internal::make_arg<Context>(
+    arg_ = detail::make_arg<Context>(
         static_cast<typename Context::char_type>(value));
   }
 
@@ -141,6 +141,13 @@ template <typename Context> class char_converter {
   void operator()(T) {}  // No conversion needed for non-integral types.
 };
 
+// An argument visitor that return a pointer to a C string if argument is a
+// string or null otherwise.
+template <typename Char> struct get_cstring {
+  template <typename T> const Char* operator()(T) { return nullptr; }
+  const Char* operator()(const Char* s) { return s; }
+};
+
 // Checks if an argument is a valid printf width specifier and sets
 // left alignment if it is negative.
 template <typename Char> class printf_width_handler {
@@ -155,7 +162,7 @@ template <typename Char> class printf_width_handler {
   template <typename T, FMT_ENABLE_IF(std::is_integral<T>::value)>
   unsigned operator()(T value) {
     auto width = static_cast<uint32_or_64_or_128_t<T>>(value);
-    if (internal::is_negative(value)) {
+    if (detail::is_negative(value)) {
       specs_.align = align::left;
       width = 0 - width;
     }
@@ -172,23 +179,25 @@ template <typename Char> class printf_width_handler {
 };
 
 template <typename Char, typename Context>
-void printf(buffer<Char>& buf, basic_string_view<Char> format,
-            basic_format_args<Context> args) {
-  Context(std::back_inserter(buf), format, args).format();
+void vprintf(buffer<Char>& buf, basic_string_view<Char> format,
+             basic_format_args<Context> args) {
+  Context(buffer_appender<Char>(buf), format, args).format();
 }
+}  // namespace detail
 
-template <typename OutputIt, typename Char, typename Context>
-internal::truncating_iterator<OutputIt> printf(
-    internal::truncating_iterator<OutputIt> it, basic_string_view<Char> format,
-    basic_format_args<Context> args) {
-  return Context(it, format, args).format();
+// For printing into memory_buffer.
+template <typename Char, typename Context>
+FMT_DEPRECATED void printf(detail::buffer<Char>& buf,
+                           basic_string_view<Char> format,
+                           basic_format_args<Context> args) {
+  return detail::vprintf(buf, format, args);
 }
-}  // namespace internal
-
-using internal::printf;  // For printing into memory_buffer.
-
-template <typename Range> class printf_arg_formatter;
+using detail::vprintf;
 
+template <typename Char>
+class basic_printf_parse_context : public basic_format_parse_context<Char> {
+  using basic_format_parse_context<Char>::basic_format_parse_context;
+};
 template <typename OutputIt, typename Char> class basic_printf_context;
 
 /**
@@ -196,15 +205,15 @@ template <typename OutputIt, typename Char> class basic_printf_context;
   The ``printf`` argument formatter.
   \endrst
  */
-template <typename Range>
-class printf_arg_formatter : public internal::arg_formatter_base<Range> {
+template <typename OutputIt, typename Char>
+class printf_arg_formatter : public detail::arg_formatter_base<OutputIt, Char> {
  public:
-  using iterator = typename Range::iterator;
+  using iterator = OutputIt;
 
  private:
-  using char_type = typename Range::value_type;
-  using base = internal::arg_formatter_base<Range>;
-  using context_type = basic_printf_context<iterator, char_type>;
+  using char_type = Char;
+  using base = detail::arg_formatter_base<OutputIt, Char>;
+  using context_type = basic_printf_context<OutputIt, Char>;
 
   context_type& context_;
 
@@ -229,9 +238,9 @@ class printf_arg_formatter : public internal::arg_formatter_base<Range> {
     \endrst
    */
   printf_arg_formatter(iterator iter, format_specs& specs, context_type& ctx)
-      : base(Range(iter), &specs, internal::locale_ref()), context_(ctx) {}
+      : base(iter, &specs, detail::locale_ref()), context_(ctx) {}
 
-  template <typename T, FMT_ENABLE_IF(fmt::internal::is_integral<T>::value)>
+  template <typename T, FMT_ENABLE_IF(fmt::detail::is_integral<T>::value)>
   iterator operator()(T value) {
     // MSVC2013 fails to compile separate overloads for bool and char_type so
     // use std::is_same instead.
@@ -246,7 +255,11 @@ class printf_arg_formatter : public internal::arg_formatter_base<Range> {
         return (*this)(static_cast<int>(value));
       fmt_specs.sign = sign::none;
       fmt_specs.alt = false;
-      fmt_specs.align = align::right;
+      fmt_specs.fill[0] = ' ';  // Ignore '0' flag for char types.
+      // align::numeric needs to be overwritten here since the '0' flag is
+      // ignored for non-numeric types
+      if (fmt_specs.align == align::none || fmt_specs.align == align::numeric)
+        fmt_specs.align = align::right;
       return base::operator()(value);
     } else {
       return base::operator()(value);
@@ -312,18 +325,21 @@ template <typename T> struct printf_formatter {
 
   template <typename FormatContext>
   auto format(const T& value, FormatContext& ctx) -> decltype(ctx.out()) {
-    internal::format_value(internal::get_container(ctx.out()), value);
+    detail::format_value(detail::get_container(ctx.out()), value);
     return ctx.out();
   }
 };
 
-/** This template formats data and writes the output to a writer. */
+/**
+ This template formats data and writes the output through an output iterator.
+ */
 template <typename OutputIt, typename Char> class basic_printf_context {
  public:
   /** The character type for the output. */
   using char_type = Char;
   using iterator = OutputIt;
   using format_arg = basic_format_arg<basic_printf_context>;
+  using parse_context_type = basic_printf_parse_context<Char>;
   template <typename T> using formatter_type = printf_formatter<T>;
 
  private:
@@ -331,7 +347,7 @@ template <typename OutputIt, typename Char> class basic_printf_context {
 
   OutputIt out_;
   basic_format_args<basic_printf_context> args_;
-  basic_format_parse_context<Char> parse_ctx_;
+  parse_context_type parse_ctx_;
 
   static void parse_flags(format_specs& specs, const Char*& it,
                           const Char* end);
@@ -346,9 +362,8 @@ template <typename OutputIt, typename Char> class basic_printf_context {
  public:
   /**
    \rst
-   Constructs a ``printf_context`` object. References to the arguments and
-   the writer are stored in the context object so make sure they have
-   appropriate lifetimes.
+   Constructs a ``printf_context`` object. References to the arguments are
+   stored in the context object so make sure they have appropriate lifetimes.
    \endrst
    */
   basic_printf_context(OutputIt out, basic_string_view<char_type> format_str,
@@ -358,18 +373,18 @@ template <typename OutputIt, typename Char> class basic_printf_context {
   OutputIt out() { return out_; }
   void advance_to(OutputIt it) { out_ = it; }
 
-  internal::locale_ref locale() { return {}; }
+  detail::locale_ref locale() { return {}; }
 
   format_arg arg(int id) const { return args_.get(id); }
 
-  basic_format_parse_context<Char>& parse_context() { return parse_ctx_; }
+  parse_context_type& parse_context() { return parse_ctx_; }
 
   FMT_CONSTEXPR void on_error(const char* message) {
     parse_ctx_.on_error(message);
   }
 
   /** Formats stored arguments and writes the output to the range. */
-  template <typename ArgFormatter = printf_arg_formatter<buffer_range<Char>>>
+  template <typename ArgFormatter = printf_arg_formatter<OutputIt, Char>>
   OutputIt format();
 };
 
@@ -389,7 +404,9 @@ void basic_printf_context<OutputIt, Char>::parse_flags(format_specs& specs,
       specs.fill[0] = '0';
       break;
     case ' ':
-      specs.sign = sign::space;
+      if (specs.sign != sign::plus) {
+        specs.sign = sign::space;
+      }
       break;
     case '#':
       specs.alt = true;
@@ -407,7 +424,7 @@ basic_printf_context<OutputIt, Char>::get_arg(int arg_index) {
     arg_index = parse_ctx_.next_arg_id();
   else
     parse_ctx_.check_arg_id(--arg_index);
-  return internal::get_arg(*this, arg_index);
+  return detail::get_arg(*this, arg_index);
 }
 
 template <typename OutputIt, typename Char>
@@ -419,7 +436,7 @@ int basic_printf_context<OutputIt, Char>::parse_header(const Char*& it,
   if (c >= '0' && c <= '9') {
     // Parse an argument index (if followed by '$') or a width possibly
     // preceded with '0' flag(s).
-    internal::error_handler eh;
+    detail::error_handler eh;
     int value = parse_nonnegative_int(it, end, eh);
     if (it != end && *it == '$') {  // value is an argument index
       ++it;
@@ -438,12 +455,12 @@ int basic_printf_context<OutputIt, Char>::parse_header(const Char*& it,
   // Parse width.
   if (it != end) {
     if (*it >= '0' && *it <= '9') {
-      internal::error_handler eh;
+      detail::error_handler eh;
       specs.width = parse_nonnegative_int(it, end, eh);
     } else if (*it == '*') {
       ++it;
       specs.width = static_cast<int>(visit_format_arg(
-          internal::printf_width_handler<char_type>(specs), get_arg()));
+          detail::printf_width_handler<char_type>(specs), get_arg()));
     }
   }
   return arg_index;
@@ -471,38 +488,52 @@ OutputIt basic_printf_context<OutputIt, Char>::format() {
 
     // Parse argument index, flags and width.
     int arg_index = parse_header(it, end, specs);
-    if (arg_index == 0) on_error("argument index out of range");
+    if (arg_index == 0) on_error("argument not found");
 
     // Parse precision.
     if (it != end && *it == '.') {
       ++it;
       c = it != end ? *it : 0;
       if ('0' <= c && c <= '9') {
-        internal::error_handler eh;
+        detail::error_handler eh;
         specs.precision = parse_nonnegative_int(it, end, eh);
       } else if (c == '*') {
         ++it;
         specs.precision = static_cast<int>(
-            visit_format_arg(internal::printf_precision_handler(), get_arg()));
+            visit_format_arg(detail::printf_precision_handler(), get_arg()));
       } else {
         specs.precision = 0;
       }
     }
 
     format_arg arg = get_arg(arg_index);
-    if (specs.alt && visit_format_arg(internal::is_zero_int(), arg))
+    // For d, i, o, u, x, and X conversion specifiers, if a precision is
+    // specified, the '0' flag is ignored
+    if (specs.precision >= 0 && arg.is_integral())
+      specs.fill[0] =
+          ' ';  // Ignore '0' flag for non-numeric types or if '-' present.
+    if (specs.precision >= 0 && arg.type() == detail::type::cstring_type) {
+      auto str = visit_format_arg(detail::get_cstring<Char>(), arg);
+      auto str_end = str + specs.precision;
+      auto nul = std::find(str, str_end, Char());
+      arg = detail::make_arg<basic_printf_context>(basic_string_view<Char>(
+          str,
+          detail::to_unsigned(nul != str_end ? nul - str : specs.precision)));
+    }
+    if (specs.alt && visit_format_arg(detail::is_zero_int(), arg))
       specs.alt = false;
     if (specs.fill[0] == '0') {
-      if (arg.is_arithmetic())
+      if (arg.is_arithmetic() && specs.align != align::left)
         specs.align = align::numeric;
       else
-        specs.fill[0] = ' ';  // Ignore '0' flag for non-numeric types.
+        specs.fill[0] = ' ';  // Ignore '0' flag for non-numeric types or if '-'
+                              // flag is also present.
     }
 
     // Parse length and convert the argument to the required type.
     c = it != end ? *it++ : 0;
     char_type t = it != end ? *it : 0;
-    using internal::convert_arg;
+    using detail::convert_arg;
     switch (c) {
     case 'h':
       if (t == 'h') {
@@ -526,7 +557,7 @@ OutputIt basic_printf_context<OutputIt, Char>::format() {
       convert_arg<intmax_t>(arg, t);
       break;
     case 'z':
-      convert_arg<std::size_t>(arg, t);
+      convert_arg<size_t>(arg, t);
       break;
     case 't':
       convert_arg<std::ptrdiff_t>(arg, t);
@@ -551,7 +582,7 @@ OutputIt basic_printf_context<OutputIt, Char>::format() {
         specs.type = 'd';
         break;
       case 'c':
-        visit_format_arg(internal::char_converter<basic_printf_context>(arg),
+        visit_format_arg(detail::char_converter<basic_printf_context>(arg),
                          arg);
         break;
       }
@@ -560,15 +591,14 @@ OutputIt basic_printf_context<OutputIt, Char>::format() {
     start = it;
 
     // Format argument.
-    visit_format_arg(ArgFormatter(out, specs, *this), arg);
+    out = visit_format_arg(ArgFormatter(out, specs, *this), arg);
   }
   return std::copy(start, it, out);
 }
 
 template <typename Char>
 using basic_printf_context_t =
-    basic_printf_context<std::back_insert_iterator<internal::buffer<Char>>,
-                         Char>;
+    basic_printf_context<detail::buffer_appender<Char>, Char>;
 
 using printf_context = basic_printf_context_t<char>;
 using wprintf_context = basic_printf_context_t<wchar_t>;
@@ -605,7 +635,7 @@ inline std::basic_string<Char> vsprintf(
     const S& format,
     basic_format_args<basic_printf_context_t<type_identity_t<Char>>> args) {
   basic_memory_buffer<Char> buffer;
-  printf(buffer, to_string_view(format), args);
+  vprintf(buffer, to_string_view(format), args);
   return to_string(buffer);
 }
 
@@ -619,7 +649,7 @@ inline std::basic_string<Char> vsprintf(
   \endrst
 */
 template <typename S, typename... Args,
-          typename Char = enable_if_t<internal::is_string<S>::value, char_t<S>>>
+          typename Char = enable_if_t<detail::is_string<S>::value, char_t<S>>>
 inline std::basic_string<Char> sprintf(const S& format, const Args&... args) {
   using context = basic_printf_context_t<Char>;
   return vsprintf(to_string_view(format), make_format_args<context>(args...));
@@ -630,8 +660,8 @@ inline int vfprintf(
     std::FILE* f, const S& format,
     basic_format_args<basic_printf_context_t<type_identity_t<Char>>> args) {
   basic_memory_buffer<Char> buffer;
-  printf(buffer, to_string_view(format), args);
-  std::size_t size = buffer.size();
+  vprintf(buffer, to_string_view(format), args);
+  size_t size = buffer.size();
   return std::fwrite(buffer.data(), sizeof(Char), size, f) < size
              ? -1
              : static_cast<int>(size);
@@ -647,7 +677,7 @@ inline int vfprintf(
   \endrst
  */
 template <typename S, typename... Args,
-          typename Char = enable_if_t<internal::is_string<S>::value, char_t<S>>>
+          typename Char = enable_if_t<detail::is_string<S>::value, char_t<S>>>
 inline int fprintf(std::FILE* f, const S& format, const Args&... args) {
   using context = basic_printf_context_t<Char>;
   return vfprintf(f, to_string_view(format),
@@ -671,7 +701,7 @@ inline int vprintf(
   \endrst
  */
 template <typename S, typename... Args,
-          FMT_ENABLE_IF(internal::is_string<S>::value)>
+          FMT_ENABLE_IF(detail::is_string<S>::value)>
 inline int printf(const S& format_str, const Args&... args) {
   using context = basic_printf_context_t<char_t<S>>;
   return vprintf(to_string_view(format_str),
@@ -683,8 +713,8 @@ inline int vfprintf(
     std::basic_ostream<Char>& os, const S& format,
     basic_format_args<basic_printf_context_t<type_identity_t<Char>>> args) {
   basic_memory_buffer<Char> buffer;
-  printf(buffer, to_string_view(format), args);
-  internal::write(os, buffer);
+  vprintf(buffer, to_string_view(format), args);
+  detail::write_buffer(os, buffer);
   return static_cast<int>(buffer.size());
 }
 
@@ -693,7 +723,7 @@ template <typename ArgFormatter, typename Char,
           typename Context =
               basic_printf_context<typename ArgFormatter::iterator, Char>>
 typename ArgFormatter::iterator vprintf(
-    internal::buffer<Char>& out, basic_string_view<Char> format_str,
+    detail::buffer<Char>& out, basic_string_view<Char> format_str,
     basic_format_args<type_identity_t<Context>> args) {
   typename ArgFormatter::iterator iter(out);
   Context(iter, format_str, args).template format<ArgFormatter>();

include/spdlog/fmt/bundled/ranges.h

@@ -33,7 +33,7 @@ template <typename Char> struct formatting_base {
 
 template <typename Char, typename Enable = void>
 struct formatting_range : formatting_base<Char> {
-  static FMT_CONSTEXPR_DECL const std::size_t range_length_limit =
+  static FMT_CONSTEXPR_DECL const size_t range_length_limit =
       FMT_RANGE_OUTPUT_LENGTH_LIMIT;  // output only up to N items from the
                                       // range.
   Char prefix;
@@ -54,7 +54,7 @@ struct formatting_tuple : formatting_base<Char> {
   static FMT_CONSTEXPR_DECL const bool add_prepostfix_space = false;
 };
 
-namespace internal {
+namespace detail {
 
 template <typename RangeT, typename OutputIterator>
 OutputIterator copy(const RangeT& range, OutputIterator out) {
@@ -118,26 +118,24 @@ template <typename T> class is_tuple_like_ {
 #if defined(__cpp_lib_integer_sequence) || FMT_MSC_VER >= 1900
 template <typename T, T... N>
 using integer_sequence = std::integer_sequence<T, N...>;
-template <std::size_t... N> using index_sequence = std::index_sequence<N...>;
-template <std::size_t N>
-using make_index_sequence = std::make_index_sequence<N>;
+template <size_t... N> using index_sequence = std::index_sequence<N...>;
+template <size_t N> using make_index_sequence = std::make_index_sequence<N>;
 #else
 template <typename T, T... N> struct integer_sequence {
   using value_type = T;
 
-  static FMT_CONSTEXPR std::size_t size() { return sizeof...(N); }
+  static FMT_CONSTEXPR size_t size() { return sizeof...(N); }
 };
 
-template <std::size_t... N>
-using index_sequence = integer_sequence<std::size_t, N...>;
+template <size_t... N> using index_sequence = integer_sequence<size_t, N...>;
 
-template <typename T, std::size_t N, T... Ns>
+template <typename T, size_t N, T... Ns>
 struct make_integer_sequence : make_integer_sequence<T, N - 1, N - 1, Ns...> {};
 template <typename T, T... Ns>
 struct make_integer_sequence<T, 0, Ns...> : integer_sequence<T, Ns...> {};
 
-template <std::size_t N>
-using make_index_sequence = make_integer_sequence<std::size_t, N>;
+template <size_t N>
+using make_index_sequence = make_integer_sequence<size_t, N>;
 #endif
 
 template <class Tuple, class F, size_t... Is>
@@ -159,6 +157,9 @@ template <class Tuple, class F> void for_each(Tuple&& tup, F&& f) {
   for_each(indexes, std::forward<Tuple>(tup), std::forward<F>(f));
 }
 
+template <typename Range>
+using value_type = remove_cvref_t<decltype(*std::declval<Range>().begin())>;
+
 template <typename Arg, FMT_ENABLE_IF(!is_like_std_string<
                                       typename std::decay<Arg>::type>::value)>
 FMT_CONSTEXPR const char* format_str_quoted(bool add_space, const Arg&) {
@@ -184,12 +185,11 @@ FMT_CONSTEXPR const char* format_str_quoted(bool add_space, const char) {
 FMT_CONSTEXPR const wchar_t* format_str_quoted(bool add_space, const wchar_t) {
   return add_space ? L" '{}'" : L"'{}'";
 }
-
-}  // namespace internal
+}  // namespace detail
 
 template <typename T> struct is_tuple_like {
   static FMT_CONSTEXPR_DECL const bool value =
-      internal::is_tuple_like_<T>::value && !internal::is_range_<T>::value;
+      detail::is_tuple_like_<T>::value && !detail::is_range_<T>::value;
 };
 
 template <typename TupleT, typename Char>
@@ -202,17 +202,17 @@ struct formatter<TupleT, Char, enable_if_t<fmt::is_tuple_like<TupleT>::value>> {
         if (formatting.add_prepostfix_space) {
           *out++ = ' ';
         }
-        out = internal::copy(formatting.delimiter, out);
+        out = detail::copy(formatting.delimiter, out);
       }
       out = format_to(out,
-                      internal::format_str_quoted(
+                      detail::format_str_quoted(
                           (formatting.add_delimiter_spaces && i > 0), v),
                       v);
       ++i;
     }
 
     formatting_tuple<Char>& formatting;
-    std::size_t& i;
+    size_t& i;
     typename std::add_lvalue_reference<decltype(
         std::declval<FormatContext>().out())>::type out;
   };
@@ -228,14 +228,14 @@ struct formatter<TupleT, Char, enable_if_t<fmt::is_tuple_like<TupleT>::value>> {
   template <typename FormatContext = format_context>
   auto format(const TupleT& values, FormatContext& ctx) -> decltype(ctx.out()) {
     auto out = ctx.out();
-    std::size_t i = 0;
-    internal::copy(formatting.prefix, out);
+    size_t i = 0;
+    detail::copy(formatting.prefix, out);
 
-    internal::for_each(values, format_each<FormatContext>{formatting, i, out});
+    detail::for_each(values, format_each<FormatContext>{formatting, i, out});
     if (formatting.add_prepostfix_space) {
       *out++ = ' ';
     }
-    internal::copy(formatting.postfix, out);
+    detail::copy(formatting.postfix, out);
 
     return ctx.out();
   }
@@ -243,15 +243,23 @@ struct formatter<TupleT, Char, enable_if_t<fmt::is_tuple_like<TupleT>::value>> {
 
 template <typename T, typename Char> struct is_range {
   static FMT_CONSTEXPR_DECL const bool value =
-      internal::is_range_<T>::value &&
-      !internal::is_like_std_string<T>::value &&
+      detail::is_range_<T>::value && !detail::is_like_std_string<T>::value &&
       !std::is_convertible<T, std::basic_string<Char>>::value &&
-      !std::is_constructible<internal::std_string_view<Char>, T>::value;
+      !std::is_constructible<detail::std_string_view<Char>, T>::value;
 };
 
-template <typename RangeT, typename Char>
-struct formatter<RangeT, Char,
-                 enable_if_t<fmt::is_range<RangeT, Char>::value>> {
+template <typename T, typename Char>
+struct formatter<
+    T, Char,
+    enable_if_t<fmt::is_range<T, Char>::value
+// Workaround a bug in MSVC 2017 and earlier.
+#if !FMT_MSC_VER || FMT_MSC_VER >= 1927
+                &&
+                (has_formatter<detail::value_type<T>, format_context>::value ||
+                 detail::has_fallback_formatter<detail::value_type<T>,
+                                                format_context>::value)
+#endif
+                >> {
   formatting_range<Char> formatting;
 
   template <typename ParseContext>
@@ -260,17 +268,18 @@ struct formatter<RangeT, Char,
   }
 
   template <typename FormatContext>
-  typename FormatContext::iterator format(const RangeT& values,
-                                          FormatContext& ctx) {
-    auto out = internal::copy(formatting.prefix, ctx.out());
-    std::size_t i = 0;
-    for (auto it = values.begin(), end = values.end(); it != end; ++it) {
+  typename FormatContext::iterator format(const T& values, FormatContext& ctx) {
+    auto out = detail::copy(formatting.prefix, ctx.out());
+    size_t i = 0;
+    auto it = values.begin();
+    auto end = values.end();
+    for (; it != end; ++it) {
       if (i > 0) {
         if (formatting.add_prepostfix_space) *out++ = ' ';
-        out = internal::copy(formatting.delimiter, out);
+        out = detail::copy(formatting.delimiter, out);
       }
       out = format_to(out,
-                      internal::format_str_quoted(
+                      detail::format_str_quoted(
                           (formatting.add_delimiter_spaces && i > 0), *it),
                       *it);
       if (++i > formatting.range_length_limit) {
@@ -279,11 +288,11 @@ struct formatter<RangeT, Char,
       }
     }
     if (formatting.add_prepostfix_space) *out++ = ' ';
-    return internal::copy(formatting.postfix, out);
+    return detail::copy(formatting.postfix, out);
   }
 };
 
-template <typename Char, typename... T> struct tuple_arg_join : internal::view {
+template <typename Char, typename... T> struct tuple_arg_join : detail::view {
   const std::tuple<T...>& tuple;
   basic_string_view<Char> sep;
 
@@ -301,14 +310,14 @@ struct formatter<tuple_arg_join<Char, T...>, Char> {
   template <typename FormatContext>
   typename FormatContext::iterator format(
       const tuple_arg_join<Char, T...>& value, FormatContext& ctx) {
-    return format(value, ctx, internal::make_index_sequence<sizeof...(T)>{});
+    return format(value, ctx, detail::make_index_sequence<sizeof...(T)>{});
   }
 
  private:
   template <typename FormatContext, size_t... N>
   typename FormatContext::iterator format(
       const tuple_arg_join<Char, T...>& value, FormatContext& ctx,
-      internal::index_sequence<N...>) {
+      detail::index_sequence<N...>) {
     return format_args(value, ctx, std::get<N>(value.tuple)...);
   }
 
@@ -371,14 +380,14 @@ FMT_CONSTEXPR tuple_arg_join<wchar_t, T...> join(const std::tuple<T...>& tuple,
   \endrst
  */
 template <typename T>
-arg_join<internal::iterator_t<const std::initializer_list<T>>, char> join(
-    std::initializer_list<T> list, string_view sep) {
+arg_join<const T*, const T*, char> join(std::initializer_list<T> list,
+                                        string_view sep) {
   return join(std::begin(list), std::end(list), sep);
 }
 
 template <typename T>
-arg_join<internal::iterator_t<const std::initializer_list<T>>, wchar_t> join(
-    std::initializer_list<T> list, wstring_view sep) {
+arg_join<const T*, const T*, wchar_t> join(std::initializer_list<T> list,
+                                           wstring_view sep) {
   return join(std::begin(list), std::end(list), sep);
 }
 

include/spdlog/fmt/chrono.h

@@ -0,0 +1,20 @@
+//
+// 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
+//
+
+#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

include/spdlog/fmt/fmt.h

@@ -17,6 +17,8 @@
 #ifndef FMT_USE_WINDOWS_H
 #define FMT_USE_WINDOWS_H 0
 #endif
+// enable the 'n' flag in for backward compatibility with fmt 6.x
+#define FMT_DEPRECATED_N_SPECIFIER
 #include <spdlog/fmt/bundled/core.h>
 #include <spdlog/fmt/bundled/format.h>
 #else // SPDLOG_FMT_EXTERNAL is defined - use external fmtlib

include/spdlog/logger-inl.h

@@ -247,7 +247,11 @@ SPDLOG_INLINE void logger::err_handler_(const std::string &msg)
         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

include/spdlog/logger.h

@@ -73,65 +73,60 @@ public:
 
     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)
+    // FormatString is a type derived from fmt::compile_string
+    template<typename FormatString, typename std::enable_if<fmt::is_compile_string<FormatString>::value, int>::type = 0, typename... Args>
+    void log(source_loc loc, level::level_enum lvl, const FormatString &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;
-            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()
+        log_(loc, lvl, fmt, std::forward<Args>(args)...);
     }
 
+    // FormatString is NOT a type derived from fmt::compile_string but is a string_view_t or can be implicitly converted to one
     template<typename... Args>
-    void log(level::level_enum lvl, string_view_t fmt, const Args &... args)
+    void log(source_loc loc, level::level_enum lvl, string_view_t fmt, Args&&...args)
     {
-        log(source_loc{}, lvl, fmt, args...);
+        log_(loc, lvl, fmt, std::forward<Args>(args)...);
     }
 
-    template<typename... Args>
-    void trace(string_view_t fmt, const Args &... args)
+    template<typename FormatString, typename... Args>
+    void log(level::level_enum lvl, const FormatString &fmt, Args&&...args)
     {
-        log(level::trace, fmt, args...);
+        log(source_loc{}, lvl, fmt, std::forward<Args>(args)...);
     }
 
-    template<typename... Args>
-    void debug(string_view_t fmt, const Args &... args)
+    template<typename FormatString, typename... Args>
+    void trace(const FormatString &fmt, Args&&...args)
     {
-        log(level::debug, fmt, args...);
+        log(level::trace, fmt, std::forward<Args>(args)...);
     }
 
-    template<typename... Args>
-    void info(string_view_t fmt, const Args &... args)
+    template<typename FormatString, typename... Args>
+    void debug(const FormatString &fmt, Args&&...args)
     {
-        log(level::info, fmt, args...);
+        log(level::debug, fmt, std::forward<Args>(args)...);
     }
 
-    template<typename... Args>
-    void warn(string_view_t fmt, const Args &... args)
+    template<typename FormatString, typename... Args>
+    void info(const FormatString &fmt, Args&&...args)
     {
-        log(level::warn, fmt, args...);
+        log(level::info, fmt, std::forward<Args>(args)...);
     }
 
-    template<typename... Args>
-    void error(string_view_t fmt, const Args &... args)
+    template<typename FormatString, typename... Args>
+    void warn(const FormatString &fmt, Args&&...args)
     {
-        log(level::err, fmt, args...);
+        log(level::warn, fmt, std::forward<Args>(args)...);
     }
 
-    template<typename... Args>
-    void critical(string_view_t fmt, const Args &... args)
+    template<typename FormatString, typename... Args>
+    void error(const FormatString &fmt, Args&&...args)
     {
-        log(level::critical, fmt, args...);
+        log(level::err, fmt, std::forward<Args>(args)...);
+    }
+
+    template<typename FormatString, typename... Args>
+    void critical(const FormatString &fmt, Args&&...args)
+    {
+        log(level::critical, fmt, std::forward<Args>(args)...);
     }
 
     template<typename T>
@@ -140,8 +135,9 @@ public:
         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>
+    // T can be statically converted to string_view and isn't a fmt::compile_string
+    template<class T, typename std::enable_if<
+                          std::is_convertible<const T &, spdlog::string_view_t>::value && !fmt::is_compile_string<T>::value, int>::type = 0>
     void log(source_loc loc, level::level_enum lvl, const T &msg)
     {
         log(loc, lvl, string_view_t{msg});
@@ -181,7 +177,7 @@ public:
     // 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>
+                          int>::type = 0>
     void log(source_loc loc, level::level_enum lvl, const T &msg)
     {
         log(loc, lvl, "{}", msg);
@@ -229,7 +225,7 @@ public:
 #else
 
     template<typename... Args>
-    void log(source_loc loc, level::level_enum lvl, wstring_view_t fmt, const Args &... 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();
@@ -241,7 +237,7 @@ public:
         {
             // format to wmemory_buffer and convert to utf8
             fmt::wmemory_buffer wbuf;
-            fmt::format_to(wbuf, fmt, args...);
+            fmt::format_to(wbuf, fmt, std::forward<Args>(args)...);
 
             memory_buf_t buf;
             details::os::wstr_to_utf8buf(wstring_view_t(wbuf.data(), wbuf.size()), buf);
@@ -251,50 +247,8 @@ public:
         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>
+    template<class T, typename std::enable_if<is_convertible_to_wstring_view<const T &>::value, int>::type = 0>
     void log(source_loc loc, level::level_enum lvl, const T &msg)
     {
         bool log_enabled = should_log(lvl);
@@ -370,6 +324,26 @@ protected:
     err_handler custom_err_handler_{nullptr};
     details::backtracer tracer_;
 
+    // common implementation for after templated public api has been resolved
+    template<typename FormatString, typename... Args>
+    void log_(source_loc loc, level::level_enum lvl, const FormatString &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;
+            fmt::format_to(buf, fmt, std::forward<Args>(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()
+    }
+
     // 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);

include/spdlog/pattern_formatter-inl.h

@@ -13,11 +13,13 @@
 #include <spdlog/fmt/fmt.h>
 #include <spdlog/formatter.h>
 
+#include <algorithm>
 #include <array>
 #include <chrono>
 #include <ctime>
 #include <cctype>
 #include <cstring>
+#include <iterator>
 #include <memory>
 #include <mutex>
 #include <string>
@@ -45,12 +47,12 @@ public:
             return;
         }
 
-        if (padinfo_.side_ == padding_info::left)
+        if (padinfo_.side_ == padding_info::pad_side::left)
         {
             pad_it(remaining_pad_);
             remaining_pad_ = 0;
         }
-        else if (padinfo_.side_ == padding_info::center)
+        else if (padinfo_.side_ == padding_info::pad_side::center)
         {
             auto half_pad = remaining_pad_ / 2;
             auto reminder = remaining_pad_ & 1;
@@ -127,7 +129,7 @@ public:
 
     void format(const details::log_msg &msg, const std::tm &, memory_buf_t &dest) override
     {
-        string_view_t &level_name = level::to_string_view(msg.level);
+        const string_view_t &level_name = level::to_string_view(msg.level);
         ScopedPadder p(level_name.size(), padinfo_, dest);
         fmt_helper::append_string_view(level_name, dest);
     }
@@ -814,11 +816,31 @@ public:
         : flag_formatter(padinfo)
     {}
 
+#ifdef _MSC_VER
+#pragma warning(push)
+#pragma warning(disable : 4127) // consider using 'if constexpr' instead
+#endif // _MSC_VER
     static const char *basename(const char *filename)
     {
-        const char *rv = std::strrchr(filename, os::folder_sep);
-        return rv != nullptr ? rv + 1 : filename;
+        // if the size is 2 (1 character + null terminator) we can use the more efficient strrchr
+        // the branch will be elided by optimizations
+        if (sizeof(os::folder_seps) == 2)
+        {
+            const char *rv = std::strrchr(filename, os::folder_seps[0]);
+            return rv != nullptr ? rv + 1 : filename;
+        }
+        else
+        {
+            const std::reverse_iterator<const char*> begin(filename + std::strlen(filename));
+            const std::reverse_iterator<const char*> end(filename);
+
+            const auto it = std::find_first_of(begin, end, std::begin(os::folder_seps), std::end(os::folder_seps) - 1);
+            return it != end ? it.base() : filename;
+        }
     }
+#ifdef _MSC_VER
+#pragma warning(pop)
+#endif // _MSC_VER
 
     void format(const details::log_msg &msg, const std::tm &, memory_buf_t &dest) override
     {
@@ -1246,9 +1268,24 @@ SPDLOG_INLINE void pattern_formatter::handle_flag_(char flag, details::padding_i
 
     default: // Unknown flag appears as is
         auto unknown_flag = details::make_unique<details::aggregate_formatter>();
-        unknown_flag->add_ch('%');
-        unknown_flag->add_ch(flag);
-        formatters_.push_back((std::move(unknown_flag)));
+
+        if (!padding.truncate_)
+        {
+            unknown_flag->add_ch('%');
+            unknown_flag->add_ch(flag);
+            formatters_.push_back((std::move(unknown_flag)));
+        }
+        // fix issue #1617 (prev char was '!' and should have been treated as funcname flag instead of truncating flag)
+        // spdlog::set_pattern("[%10!] %v") => "[      main] some message"
+        // spdlog::set_pattern("[%3!!] %v") => "[mai] some message"
+        else
+        {
+            padding.truncate_ = false;
+            formatters_.push_back(details::make_unique<details::source_funcname_formatter<Padder>>(padding));
+            unknown_flag->add_ch(flag);
+            formatters_.push_back((std::move(unknown_flag)));
+        }
+
         break;
     }
 }
@@ -1270,15 +1307,15 @@ SPDLOG_INLINE details::padding_info pattern_formatter::handle_padspec_(std::stri
     switch (*it)
     {
     case '-':
-        side = padding_info::right;
+        side = padding_info::pad_side::right;
         ++it;
         break;
     case '=':
-        side = padding_info::center;
+        side = padding_info::pad_side::center;
         ++it;
         break;
     default:
-        side = details::padding_info::left;
+        side = details::padding_info::pad_side::left;
         break;
     }
 

include/spdlog/pattern_formatter.h

@@ -22,7 +22,7 @@ namespace details {
 // padding information.
 struct padding_info
 {
-    enum pad_side
+    enum class pad_side
     {
         left,
         right,
@@ -42,7 +42,7 @@ struct padding_info
         return enabled_;
     }
     size_t width_ = 0;
-    pad_side side_ = left;
+    pad_side side_ = pad_side::left;
     bool truncate_ = false;
     bool enabled_ = false;
 };
@@ -92,9 +92,9 @@ public:
     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)
+    pattern_formatter &add_flag(char flag, Args&&...args)
     {
-        custom_handlers_[flag] = details::make_unique<T>(args...);
+        custom_handlers_[flag] = details::make_unique<T>(std::forward<Args>(args)...);
         return *this;
     }
     void set_pattern(std::string pattern);

include/spdlog/sinks/ansicolor_sink-inl.h

@@ -106,6 +106,8 @@ SPDLOG_INLINE void ansicolor_sink<ConsoleMutex>::set_color_mode(color_mode mode)
     case color_mode::never:
         should_do_colors_ = false;
         return;
+    default:
+        should_do_colors_ = false;
     }
 }
 

include/spdlog/sinks/daily_file_sink.h

@@ -7,6 +7,7 @@
 #include <spdlog/details/file_helper.h>
 #include <spdlog/details/null_mutex.h>
 #include <spdlog/fmt/fmt.h>
+#include <spdlog/fmt/chrono.h>
 #include <spdlog/sinks/base_sink.h>
 #include <spdlog/details/os.h>
 #include <spdlog/details/circular_q.h>
@@ -36,6 +37,23 @@ struct daily_filename_calculator
     }
 };
 
+/*
+ * Generator of daily log file names with strftime format.
+ * Usages:  
+ *    auto sink =  std::make_shared<spdlog::sinks::daily_file_format_sink_mt>("myapp-%Y-%m-%d:%H:%M:%S.log", hour, minute);"
+ *    auto logger = spdlog::daily_logger_format_mt("loggername, "myapp-%Y-%m-%d:%X.log", hour,  minute)"
+ *  
+ */
+struct daily_filename_format_calculator
+{
+    static filename_t calc_filename (const filename_t &filename, const tm &now_tm)
+    {
+         // generate fmt datetime format string, e.g. {:%Y-%m-%d}.
+        filename_t fmt_filename = fmt::format(SPDLOG_FILENAME_T ("{{:{}}}"), filename);
+        return fmt::format(fmt_filename, now_tm);
+    }
+};
+
 /*
  * Rotating file sink based on date.
  * If truncate != false , the created file will be truncated.
@@ -155,7 +173,7 @@ private:
         using details::os::filename_to_str;
         using details::os::remove_if_exists;
 
-        filename_t current_file = filename();
+        filename_t current_file = file_helper_.filename();
         if (filenames_q_.full())
         {
             auto old_filename = std::move(filenames_q_.front());
@@ -182,6 +200,8 @@ private:
 
 using daily_file_sink_mt = daily_file_sink<std::mutex>;
 using daily_file_sink_st = daily_file_sink<details::null_mutex>;
+using daily_file_format_sink_mt = daily_file_sink<std::mutex, daily_filename_format_calculator>;
+using daily_file_format_sink_st = daily_file_sink<details::null_mutex, daily_filename_format_calculator>;
 
 } // namespace sinks
 
@@ -195,10 +215,24 @@ inline std::shared_ptr<logger> daily_logger_mt(
     return Factory::template create<sinks::daily_file_sink_mt>(logger_name, filename, hour, minute, truncate, max_files);
 }
 
+template<typename Factory = spdlog::synchronous_factory>
+inline std::shared_ptr<logger> daily_logger_format_mt(
+    const std::string &logger_name, const filename_t &filename, int hour = 0, int minute = 0, bool truncate = false, uint16_t max_files = 0)
+{
+    return Factory::template create<sinks::daily_file_format_sink_mt>(logger_name, filename, hour, minute, truncate, max_files);
+}
+
 template<typename Factory = spdlog::synchronous_factory>
 inline std::shared_ptr<logger> daily_logger_st(
     const std::string &logger_name, const filename_t &filename, int hour = 0, int minute = 0, bool truncate = false, uint16_t max_files = 0)
 {
     return Factory::template create<sinks::daily_file_sink_st>(logger_name, filename, hour, minute, truncate, max_files);
 }
+
+template<typename Factory = spdlog::synchronous_factory>
+inline std::shared_ptr<logger> daily_logger_format_st(
+    const std::string &logger_name, const filename_t &filename, int hour = 0, int minute = 0, bool truncate = false, uint16_t max_files = 0)
+{
+    return Factory::template create<sinks::daily_file_format_sink_st>(logger_name, filename, hour, minute, truncate, max_files);
+}
 } // namespace spdlog

include/spdlog/sinks/dup_filter_sink.h

@@ -64,7 +64,7 @@ protected:
         {
             memory_buf_t buf;
             fmt::format_to(buf, "Skipped {} duplicate messages..", skip_counter_);
-            details::log_msg skipped_msg{msg.logger_name, msg.level, string_view_t{buf.data(), buf.size()}};
+            details::log_msg skipped_msg{msg.logger_name, level::info, string_view_t{buf.data(), buf.size()}};
             dist_sink<Mutex>::sink_it_(skipped_msg);
         }
 

include/spdlog/sinks/hourly_file_sink.h

@@ -0,0 +1,194 @@
+// 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 <spdlog/details/file_helper.h>
+#include <spdlog/details/null_mutex.h>
+#include <spdlog/fmt/fmt.h>
+#include <spdlog/sinks/base_sink.h>
+#include <spdlog/details/os.h>
+#include <spdlog/details/circular_q.h>
+#include <spdlog/details/synchronous_factory.h>
+
+#include <chrono>
+#include <cstdio>
+#include <ctime>
+#include <mutex>
+#include <string>
+
+namespace spdlog {
+namespace sinks {
+
+/*
+ * Generator of Hourly log file names in format basename.YYYY-MM-DD-HH.ext
+ */
+struct hourly_filename_calculator
+{
+    // Create filename for the form basename.YYYY-MM-DD-H
+    static filename_t calc_filename(const filename_t &filename, const tm &now_tm)
+    {
+        filename_t basename, ext;
+        std::tie(basename, ext) = details::file_helper::split_by_extension(filename);
+        return fmt::format(
+            SPDLOG_FILENAME_T("{}_{:04d}{:02d}{:02d}_{:02d}{}"), basename, now_tm.tm_year + 1900, now_tm.tm_mon + 1, now_tm.tm_mday, now_tm.tm_hour, ext);
+    }
+};
+
+/*
+ * Rotating file sink based on time.
+ * If truncate != false , the created file will be truncated.
+ * If max_files > 0, retain only the last max_files and delete previous.
+ */
+template<typename Mutex, typename FileNameCalc = hourly_filename_calculator>
+class hourly_file_sink final : public base_sink<Mutex>
+{
+public:
+    // create hourly file sink which rotates on given time
+    hourly_file_sink(filename_t base_filename, bool truncate = false, uint16_t max_files = 0)
+        : base_filename_(std::move(base_filename))
+        , truncate_(truncate)
+        , max_files_(max_files)
+        , filenames_q_()
+    {
+        auto now = log_clock::now();
+        auto filename = FileNameCalc::calc_filename(base_filename_, now_tm(now));
+        file_helper_.open(filename, truncate_);
+        rotation_tp_ = next_rotation_tp_();
+
+        if (max_files_ > 0)
+        {
+            init_filenames_q_();
+        }
+    }
+
+    filename_t filename()
+    {
+        std::lock_guard<Mutex> lock(base_sink<Mutex>::mutex_);
+        return file_helper_.filename();
+    }
+
+protected:
+    void sink_it_(const details::log_msg &msg) override
+    {
+        auto time = msg.time;
+        bool should_rotate = time >= rotation_tp_;
+        if (should_rotate)
+        {
+            auto filename = FileNameCalc::calc_filename(base_filename_, now_tm(time));
+            file_helper_.open(filename, truncate_);
+            rotation_tp_ = next_rotation_tp_();
+        }
+        memory_buf_t formatted;
+        base_sink<Mutex>::formatter_->format(msg, formatted);
+        file_helper_.write(formatted);
+
+        // Do the cleaning only at the end because it might throw on failure.
+        if (should_rotate && max_files_ > 0)
+        {
+            delete_old_();
+        }
+    }
+
+    void flush_() override
+    {
+        file_helper_.flush();
+    }
+
+private:
+    void init_filenames_q_()
+    {
+        using details::os::path_exists;
+
+        filenames_q_ = details::circular_q<filename_t>(static_cast<size_t>(max_files_));
+        std::vector<filename_t> filenames;
+        auto now = log_clock::now();
+        while (filenames.size() < max_files_)
+        {
+            auto filename = FileNameCalc::calc_filename(base_filename_, now_tm(now));
+            if (!path_exists(filename))
+            {
+                break;
+            }
+            filenames.emplace_back(filename);
+            now -= std::chrono::hours(1);
+        }
+        for (auto iter = filenames.rbegin(); iter != filenames.rend(); ++iter)
+        {
+            filenames_q_.push_back(std::move(*iter));
+        }
+    }
+
+    tm now_tm(log_clock::time_point tp)
+    {
+        time_t tnow = log_clock::to_time_t(tp);
+        return spdlog::details::os::localtime(tnow);
+    }
+
+    log_clock::time_point next_rotation_tp_()
+    {
+        auto now = log_clock::now();
+        tm date = now_tm(now);
+        date.tm_min = 0;
+        date.tm_sec = 0;
+        auto rotation_time = log_clock::from_time_t(std::mktime(&date));
+        if (rotation_time > now)
+        {
+            return rotation_time;
+        }
+        return {rotation_time + std::chrono::hours(1)};
+    }
+
+    // Delete the file N rotations ago.
+    // Throw spdlog_ex on failure to delete the old file.
+    void delete_old_()
+    {
+        using details::os::filename_to_str;
+        using details::os::remove_if_exists;
+
+        filename_t current_file = file_helper_.filename();
+        if (filenames_q_.full())
+        {
+            auto old_filename = std::move(filenames_q_.front());
+            filenames_q_.pop_front();
+            bool ok = remove_if_exists(old_filename) == 0;
+            if (!ok)
+            {
+                filenames_q_.push_back(std::move(current_file));
+                SPDLOG_THROW(spdlog_ex("Failed removing hourly file " + filename_to_str(old_filename), errno));
+            }
+        }
+        filenames_q_.push_back(std::move(current_file));
+    }
+
+    filename_t base_filename_;
+    log_clock::time_point rotation_tp_;
+    details::file_helper file_helper_;
+    bool truncate_;
+    uint16_t max_files_;
+    details::circular_q<filename_t> filenames_q_;
+};
+
+using hourly_file_sink_mt = hourly_file_sink<std::mutex>;
+using hourly_file_sink_st = hourly_file_sink<details::null_mutex>;
+
+} // namespace sinks
+
+//
+// factory functions
+//
+template<typename Factory = spdlog::synchronous_factory>
+inline std::shared_ptr<logger> hourly_logger_mt(
+    const std::string &logger_name, const filename_t &filename, bool truncate = false, uint16_t max_files = 0)
+{
+    return Factory::template create<sinks::hourly_file_sink_mt>(logger_name, filename, truncate, max_files);
+}
+
+template<typename Factory = spdlog::synchronous_factory>
+inline std::shared_ptr<logger> hourly_logger_st(
+    const std::string &logger_name, const filename_t &filename, bool truncate = false, uint16_t max_files = 0)
+{
+    return Factory::template create<sinks::hourly_file_sink_st>(logger_name, filename, truncate, max_files);
+}
+} // namespace spdlog

include/spdlog/sinks/msvc_sink.h

@@ -8,12 +8,13 @@
 #include <spdlog/details/null_mutex.h>
 #include <spdlog/sinks/base_sink.h>
 
-#include <spdlog/details/windows_include.h>
-#include <winbase.h>
-
 #include <mutex>
 #include <string>
 
+
+// Avoid including windows.h (https://stackoverflow.com/a/30741042)
+extern "C" __declspec(dllimport) void __stdcall OutputDebugStringA(const char *lpOutputString);
+
 namespace spdlog {
 namespace sinks {
 /*
@@ -23,12 +24,11 @@ template<typename Mutex>
 class msvc_sink : public base_sink<Mutex>
 {
 public:
-    explicit msvc_sink() {}
+    msvc_sink() = default;
 
 protected:
     void sink_it_(const details::log_msg &msg) override
     {
-
         memory_buf_t formatted;
         base_sink<Mutex>::formatter_->format(msg, formatted);
         OutputDebugStringA(fmt::to_string(formatted).c_str());

include/spdlog/sinks/ringbuffer_sink.h

@@ -28,10 +28,11 @@ public:
     std::vector<details::log_msg_buffer> last_raw(size_t lim = 0)
     {
         std::lock_guard<Mutex> lock(base_sink<Mutex>::mutex_);
-        auto n_items = lim > 0 ? (std::min)(lim, q_.size()) : q_.size();
+        auto items_available = q_.size();
+        auto n_items = lim > 0 ? (std::min)(lim, items_available) : items_available;
         std::vector<details::log_msg_buffer> ret;
         ret.reserve(n_items);
-        for (size_t i = 0; i < n_items; i++)
+        for (size_t i = (items_available - n_items); i < items_available; i++)
         {
             ret.push_back(q_.at(i));
         }
@@ -41,10 +42,11 @@ public:
     std::vector<std::string> last_formatted(size_t lim = 0)
     {
         std::lock_guard<Mutex> lock(base_sink<Mutex>::mutex_);
-        auto n_items = lim > 0 ? (std::min)(lim, q_.size()) : q_.size();
+        auto items_available = q_.size();
+        auto n_items = lim > 0 ? (std::min)(lim, items_available) : items_available;
         std::vector<std::string> ret;
         ret.reserve(n_items);
-        for (size_t i = 0; i < n_items; i++)
+        for (size_t i = (items_available - n_items); i < items_available; i++)
         {
             memory_buf_t formatted;
             base_sink<Mutex>::formatter_->format(q_.at(i), formatted);

include/spdlog/sinks/stdout_sinks-inl.h

@@ -11,6 +11,15 @@
 #include <spdlog/pattern_formatter.h>
 #include <memory>
 
+#ifdef _WIN32
+// under windows using fwrite to non-binary stream results in \r\r\n (see issue #1675)
+// so instead we use ::FileWrite
+#include <spdlog/details/windows_include.h>
+#include <fileapi.h> // WriteFile (..)
+#include <io.h>      // _get_osfhandle(..)
+#include <stdio.h>   // _fileno(..)
+#endif               // WIN32
+
 namespace spdlog {
 
 namespace sinks {
@@ -20,16 +29,48 @@ SPDLOG_INLINE stdout_sink_base<ConsoleMutex>::stdout_sink_base(FILE *file)
     : mutex_(ConsoleMutex::mutex())
     , file_(file)
     , formatter_(details::make_unique<spdlog::pattern_formatter>())
-{}
+{
+#ifdef _WIN32
+    // get windows handle from the FILE* object
+    
+    handle_ = (HANDLE)::_get_osfhandle(::_fileno(file_));    
+        
+    // don't throw to support cases where no console is attached,
+    // and let the log method to do nothing if (handle_ == INVALID_HANDLE_VALUE).
+    // throw only if non stdout/stderr target is requested (probably regular file and not console).
+    if (handle_ == INVALID_HANDLE_VALUE && file != stdout && file != stderr)
+    {
+        throw_spdlog_ex("spdlog::stdout_sink_base: _get_osfhandle() failed", errno);
+    }
+#endif // WIN32
+}
 
 template<typename ConsoleMutex>
 SPDLOG_INLINE void stdout_sink_base<ConsoleMutex>::log(const details::log_msg &msg)
 {
+#ifdef _WIN32
+    if (handle_ == INVALID_HANDLE_VALUE)
+    {        
+        return;
+    }
     std::lock_guard<mutex_t> lock(mutex_);
     memory_buf_t formatted;
     formatter_->format(msg, formatted);
-    fwrite(formatted.data(), sizeof(char), formatted.size(), file_);
-    fflush(file_); // flush every line to terminal
+    ::fflush(file_); // flush in case there is somthing in this file_ already
+    auto size = static_cast<DWORD>(formatted.size());
+    DWORD bytes_written = 0;
+    bool ok = ::WriteFile(handle_, formatted.data(), size, &bytes_written, nullptr) != 0;
+    if (!ok)
+    {
+        throw_spdlog_ex("stdout_sink_base: WriteFile() failed. GetLastError(): " + std::to_string(::GetLastError()));
+    }
+#else
+    std::lock_guard<mutex_t> lock(mutex_);
+    memory_buf_t formatted;
+    formatter_->format(msg, formatted);
+    ::fwrite(formatted.data(), sizeof(char), formatted.size(), file_);
+    ::fflush(file_); // flush every line to terminal
+#endif // WIN32    
 }
 
 template<typename ConsoleMutex>

include/spdlog/sinks/stdout_sinks.h

@@ -8,6 +8,10 @@
 #include <spdlog/sinks/sink.h>
 #include <cstdio>
 
+#ifdef _WIN32
+#include <spdlog/details/windows_include.h>
+#endif
+
 namespace spdlog {
 
 namespace sinks {
@@ -36,6 +40,9 @@ protected:
     mutex_t &mutex_;
     FILE *file_;
     std::unique_ptr<spdlog::formatter> formatter_;
+#ifdef _WIN32
+    HANDLE handle_;    
+#endif // WIN32
 };
 
 template<typename ConsoleMutex>

include/spdlog/sinks/win_eventlog_sink.h

@@ -57,7 +57,7 @@ struct win32_error : public spdlog_ex
 
         LPSTR format_message_result{};
         auto format_message_succeeded =
-            ::FormatMessage(FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS, nullptr,
+            ::FormatMessageA(FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS, nullptr,
                 error_code, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), (LPSTR)&format_message_result, 0, nullptr);
 
         if (format_message_succeeded && format_message_result)
@@ -203,7 +203,7 @@ private:
     {
         if (!hEventLog_)
         {
-            hEventLog_ = ::RegisterEventSource(nullptr, source_.c_str());
+            hEventLog_ = ::RegisterEventSourceA(nullptr, source_.c_str());
             if (!hEventLog_ || hEventLog_ == (HANDLE)ERROR_ACCESS_DENIED)
             {
                 SPDLOG_THROW(internal::win32_error("RegisterEventSource"));
@@ -218,13 +218,23 @@ protected:
     {
         using namespace internal;
 
+        bool succeeded;
         memory_buf_t formatted;
         base_sink<Mutex>::formatter_->format(msg, formatted);
         formatted.push_back('\0');
-        LPCSTR lp_str = static_cast<LPCSTR>(formatted.data());
 
-        auto succeeded = ::ReportEvent(event_log_handle(), eventlog::get_event_type(msg), eventlog::get_event_category(msg), event_id_,
-            current_user_sid_.as_sid(), 1, 0, &lp_str, nullptr);
+#ifdef SPDLOG_WCHAR_TO_UTF8_SUPPORT
+        wmemory_buf_t buf;
+        details::os::utf8_to_wstrbuf(string_view_t(formatted.data(), formatted.size()), buf);
+
+        LPCWSTR lp_wstr = buf.data();
+        succeeded = ::ReportEventW(event_log_handle(), eventlog::get_event_type(msg), eventlog::get_event_category(msg), event_id_,
+                current_user_sid_.as_sid(), 1, 0, &lp_wstr, nullptr);
+#else
+        LPCSTR lp_str = formatted.data();
+        succeeded = ::ReportEventA(event_log_handle(), eventlog::get_event_type(msg), eventlog::get_event_category(msg), event_id_,
+                current_user_sid_.as_sid(), 1, 0, &lp_str, nullptr);
+#endif
 
         if (!succeeded)
         {

include/spdlog/sinks/wincolor_sink-inl.h

@@ -7,30 +7,30 @@
 #include <spdlog/sinks/wincolor_sink.h>
 #endif
 
+#include <spdlog/details/windows_include.h>
+#include <wincon.h>
+
 #include <spdlog/common.h>
 #include <spdlog/pattern_formatter.h>
 
 namespace spdlog {
 namespace sinks {
-
 template<typename ConsoleMutex>
-SPDLOG_INLINE wincolor_sink<ConsoleMutex>::wincolor_sink(HANDLE out_handle, color_mode mode)
+SPDLOG_INLINE wincolor_sink<ConsoleMutex>::wincolor_sink(void *out_handle, color_mode mode)
     : out_handle_(out_handle)
     , mutex_(ConsoleMutex::mutex())
     , formatter_(details::make_unique<spdlog::pattern_formatter>())
 {
-    // check if out_handle is points to the actual console.
-    // ::GetConsoleMode() should return 0 if it is redirected or not valid console handle.
-    DWORD console_mode;
-    in_console_ = ::GetConsoleMode(out_handle, &console_mode) != 0;
 
-    set_color_mode(mode);
-    colors_[level::trace] = WHITE;
-    colors_[level::debug] = CYAN;
-    colors_[level::info] = GREEN;
-    colors_[level::warn] = YELLOW | BOLD;
-    colors_[level::err] = RED | BOLD;                         // red bold
-    colors_[level::critical] = BACKGROUND_RED | WHITE | BOLD; // white bold on red background
+    set_color_mode_impl(mode);
+    // set level colors
+    colors_[level::trace] = FOREGROUND_RED | FOREGROUND_GREEN | FOREGROUND_BLUE;     // white
+    colors_[level::debug] = FOREGROUND_GREEN | FOREGROUND_BLUE;                      // cyan
+    colors_[level::info] = FOREGROUND_GREEN;                                         // green
+    colors_[level::warn] = FOREGROUND_RED | FOREGROUND_GREEN | FOREGROUND_INTENSITY; // intense yellow
+    colors_[level::err] = FOREGROUND_RED | FOREGROUND_INTENSITY;                     // intense red
+    colors_[level::critical] =
+        BACKGROUND_RED | FOREGROUND_RED | FOREGROUND_GREEN | FOREGROUND_BLUE | FOREGROUND_INTENSITY; // intense white on red background
     colors_[level::off] = 0;
 }
 
@@ -42,7 +42,7 @@ SPDLOG_INLINE wincolor_sink<ConsoleMutex>::~wincolor_sink()
 
 // change the color for the given level
 template<typename ConsoleMutex>
-void SPDLOG_INLINE wincolor_sink<ConsoleMutex>::set_color(level::level_enum level, WORD color)
+void SPDLOG_INLINE wincolor_sink<ConsoleMutex>::set_color(level::level_enum level, std::uint16_t color)
 {
     std::lock_guard<mutex_t> lock(mutex_);
     colors_[level] = color;
@@ -51,31 +51,30 @@ void SPDLOG_INLINE wincolor_sink<ConsoleMutex>::set_color(level::level_enum leve
 template<typename ConsoleMutex>
 void SPDLOG_INLINE wincolor_sink<ConsoleMutex>::log(const details::log_msg &msg)
 {
+    if (out_handle_ == nullptr || out_handle_ == INVALID_HANDLE_VALUE)
+    {
+        return;
+    }
+
     std::lock_guard<mutex_t> lock(mutex_);
     msg.color_range_start = 0;
     msg.color_range_end = 0;
     memory_buf_t formatted;
     formatter_->format(msg, formatted);
-    if (!in_console_)
-    {
-        write_to_file_(formatted);
-        return;
-    }
     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
-        auto orig_attribs = set_foreground_color_(colors_[msg.level]);
+        auto orig_attribs = static_cast<WORD>(set_foreground_color_(colors_[msg.level]));
         print_range_(formatted, msg.color_range_start, msg.color_range_end);
         // reset to orig colors
-        ::SetConsoleTextAttribute(out_handle_, orig_attribs);
+        ::SetConsoleTextAttribute(static_cast<HANDLE>(out_handle_), orig_attribs);
         print_range_(formatted, msg.color_range_end, formatted.size());
     }
     else // print without colors if color range is invalid (or color is disabled)
     {
-        print_range_(formatted, 0, formatted.size());
+        write_to_file_(formatted);
     }
 }
 
@@ -102,66 +101,63 @@ void SPDLOG_INLINE wincolor_sink<ConsoleMutex>::set_formatter(std::unique_ptr<sp
 template<typename ConsoleMutex>
 void SPDLOG_INLINE wincolor_sink<ConsoleMutex>::set_color_mode(color_mode mode)
 {
-    switch (mode)
+    std::lock_guard<mutex_t> lock(mutex_);
+    set_color_mode_impl(mode);
+}
+
+template<typename ConsoleMutex>
+void SPDLOG_INLINE wincolor_sink<ConsoleMutex>::set_color_mode_impl(color_mode mode)
+{
+    if (mode == color_mode::automatic)
     {
-    case color_mode::always:
-    case color_mode::automatic:
-        should_do_colors_ = true;
-        break;
-    case color_mode::never:
-        should_do_colors_ = false;
-        break;
-    default:
-        should_do_colors_ = true;
+        // should do colors only if out_handle_  points to actual console.
+        DWORD console_mode;
+        bool in_console = ::GetConsoleMode(static_cast<HANDLE>(out_handle_), &console_mode) != 0;
+        should_do_colors_ = in_console;
+    }
+    else
+    {
+        should_do_colors_ = mode == color_mode::always ? true : false;
     }
 }
 
 // set foreground color and return the orig console attributes (for resetting later)
 template<typename ConsoleMutex>
-WORD SPDLOG_INLINE wincolor_sink<ConsoleMutex>::set_foreground_color_(WORD attribs)
+std::uint16_t SPDLOG_INLINE wincolor_sink<ConsoleMutex>::set_foreground_color_(std::uint16_t attribs)
 {
     CONSOLE_SCREEN_BUFFER_INFO orig_buffer_info;
-    ::GetConsoleScreenBufferInfo(out_handle_, &orig_buffer_info);
-    WORD back_color = orig_buffer_info.wAttributes;
-    // retrieve the current background color
-    back_color &= static_cast<WORD>(~(FOREGROUND_RED | FOREGROUND_GREEN | FOREGROUND_BLUE | FOREGROUND_INTENSITY));
-    // keep the background color unchanged
-    ::SetConsoleTextAttribute(out_handle_, attribs | back_color);
-    return orig_buffer_info.wAttributes; // return orig attribs
+    if (!::GetConsoleScreenBufferInfo(static_cast<HANDLE>(out_handle_), &orig_buffer_info))
+    {
+        // just return white if failed getting console info
+        return FOREGROUND_RED | FOREGROUND_GREEN | FOREGROUND_BLUE; 
+    }
+    
+    // change only the foreground bits (lowest 4 bits) 
+    auto new_attribs = static_cast<WORD>(attribs) | (orig_buffer_info.wAttributes & 0xfff0);
+    auto ignored = ::SetConsoleTextAttribute(static_cast<HANDLE>(out_handle_), static_cast<WORD>(new_attribs));
+    (void)(ignored);
+    return static_cast<std::uint16_t>(orig_buffer_info.wAttributes); // return orig attribs
 }
 
 // print a range of formatted message to console
 template<typename ConsoleMutex>
 void SPDLOG_INLINE wincolor_sink<ConsoleMutex>::print_range_(const memory_buf_t &formatted, size_t start, size_t end)
 {
-    auto size = static_cast<DWORD>(end - start);
-    ::WriteConsoleA(out_handle_, formatted.data() + start, size, nullptr, nullptr);
+    if (end > start)
+    {
+        auto size = static_cast<DWORD>(end - start);
+        auto ignored = ::WriteConsoleA(static_cast<HANDLE>(out_handle_), formatted.data() + start, size, nullptr, nullptr);
+        (void)(ignored);
+    }
 }
 
 template<typename ConsoleMutex>
 void SPDLOG_INLINE wincolor_sink<ConsoleMutex>::write_to_file_(const memory_buf_t &formatted)
 {
-    if (out_handle_ == nullptr) // no console and no file redirect
-    {
-        return;
-    }
     auto size = static_cast<DWORD>(formatted.size());
-    if (size == 0)
-    {
-        return;
-    }
-
-    DWORD total_written = 0;
-    do
-    {
-        DWORD bytes_written = 0;
-        bool ok = ::WriteFile(out_handle_, formatted.data() + total_written, size - total_written, &bytes_written, nullptr) != 0;
-        if (!ok || bytes_written == 0)
-        {
-            throw_spdlog_ex("wincolor_sink: write_to_file_ failed. GetLastError(): " + std::to_string(::GetLastError()));
-        }
-        total_written += bytes_written;
-    } while (total_written < size);
+    DWORD bytes_written = 0;
+    auto ignored = ::WriteFile(static_cast<HANDLE>(out_handle_), formatted.data(), size, &bytes_written, nullptr);
+    (void)(ignored);
 }
 
 // wincolor_stdout_sink
@@ -175,6 +171,5 @@ template<typename ConsoleMutex>
 SPDLOG_INLINE wincolor_stderr_sink<ConsoleMutex>::wincolor_stderr_sink(color_mode mode)
     : wincolor_sink<ConsoleMutex>(::GetStdHandle(STD_ERROR_HANDLE), mode)
 {}
-
 } // namespace sinks
 } // namespace spdlog

include/spdlog/sinks/wincolor_sink.h

@@ -12,9 +12,7 @@
 #include <mutex>
 #include <string>
 #include <array>
-
-#include <spdlog/details/windows_include.h>
-#include <wincon.h>
+#include <cstdint>
 
 namespace spdlog {
 namespace sinks {
@@ -25,22 +23,15 @@ namespace sinks {
 template<typename ConsoleMutex>
 class wincolor_sink : public sink
 {
-public:
-    const WORD BOLD = FOREGROUND_INTENSITY;
-    const WORD RED = FOREGROUND_RED;
-    const WORD GREEN = FOREGROUND_GREEN;
-    const WORD CYAN = FOREGROUND_GREEN | FOREGROUND_BLUE;
-    const WORD WHITE = FOREGROUND_RED | FOREGROUND_GREEN | FOREGROUND_BLUE;
-    const WORD YELLOW = FOREGROUND_RED | FOREGROUND_GREEN;
-
-    wincolor_sink(HANDLE out_handle, color_mode mode);
+public:   
+    wincolor_sink(void *out_handle, color_mode mode);
     ~wincolor_sink() override;
 
     wincolor_sink(const wincolor_sink &other) = delete;
     wincolor_sink &operator=(const wincolor_sink &other) = delete;
 
     // change the color for the given level
-    void set_color(level::level_enum level, WORD color);
+    void set_color(level::level_enum level, std::uint16_t color);
     void log(const details::log_msg &msg) final override;
     void flush() final override;
     void set_pattern(const std::string &pattern) override final;
@@ -49,21 +40,22 @@ public:
 
 protected:
     using mutex_t = typename ConsoleMutex::mutex_t;
-    HANDLE out_handle_;
-    mutex_t &mutex_;
-    bool in_console_;
+    void *out_handle_;
+    mutex_t &mutex_;    
     bool should_do_colors_;
     std::unique_ptr<spdlog::formatter> formatter_;
-    std::array<WORD, level::n_levels> colors_;
+    std::array<std::uint16_t, level::n_levels> colors_;
 
     // set foreground color and return the orig console attributes (for resetting later)
-    WORD set_foreground_color_(WORD attribs);
+    std::uint16_t set_foreground_color_(std::uint16_t attribs);
 
     // print a range of formatted message to console
     void print_range_(const memory_buf_t &formatted, size_t start, size_t end);
 
     // in case we are redirected to file (not in console mode)
     void write_to_file_(const memory_buf_t &formatted);
+
+    void set_color_mode_impl(color_mode mode);
 };
 
 template<typename ConsoleMutex>
@@ -85,7 +77,6 @@ using wincolor_stdout_sink_st = wincolor_stdout_sink<details::console_nullmutex>
 
 using wincolor_stderr_sink_mt = wincolor_stderr_sink<details::console_mutex>;
 using wincolor_stderr_sink_st = wincolor_stderr_sink<details::console_nullmutex>;
-
 } // namespace sinks
 } // namespace spdlog
 

include/spdlog/spdlog-inl.h

@@ -47,6 +47,16 @@ SPDLOG_INLINE void dump_backtrace()
     default_logger_raw()->dump_backtrace();
 }
 
+SPDLOG_INLINE level::level_enum get_level()
+{
+    return default_logger_raw()->level();
+}
+
+SPDLOG_INLINE bool should_log(level::level_enum log_level)
+{
+    return default_logger_raw()->should_log(log_level);
+}
+
 SPDLOG_INLINE void set_level(level::level_enum log_level)
 {
     details::registry::instance().set_level(log_level);
@@ -112,4 +122,4 @@ SPDLOG_INLINE void set_default_logger(std::shared_ptr<spdlog::logger> default_lo
     details::registry::instance().set_default_logger(std::move(default_logger));
 }
 
-} // namespace spdlog
+} // namespace spdlog

include/spdlog/spdlog.h

@@ -31,7 +31,7 @@ using default_factory = synchronous_factory;
 // Example:
 //   spdlog::create<daily_file_sink_st>("logger_name", "dailylog_filename", 11, 59);
 template<typename Sink, typename... SinkArgs>
-inline std::shared_ptr<spdlog::logger> create(std::string logger_name, SinkArgs &&... sink_args)
+inline std::shared_ptr<spdlog::logger> create(std::string logger_name, SinkArgs &&...sink_args)
 {
     return default_factory::create<Sink>(std::move(logger_name), std::forward<SinkArgs>(sink_args)...);
 }
@@ -67,9 +67,15 @@ SPDLOG_API void disable_backtrace();
 // call dump backtrace on default logger
 SPDLOG_API void dump_backtrace();
 
+// Get global logging level
+SPDLOG_API level::level_enum get_level();
+
 // Set global logging level
 SPDLOG_API void set_level(level::level_enum log_level);
 
+// Determine whether the default logger should log messages with a certain level
+SPDLOG_API bool should_log(level::level_enum lvl);
+
 // Set global flush level
 SPDLOG_API void flush_on(level::level_enum log_level);
 
@@ -105,7 +111,7 @@ SPDLOG_API void set_automatic_registration(bool automatic_registration);
 //
 // The default logger object can be accessed using the spdlog::default_logger():
 // For example, to add another sink to it:
-// spdlog::default_logger()->sinks()->push_back(some_sink);
+// spdlog::default_logger()->sinks().push_back(some_sink);
 //
 // The default logger can replaced using spdlog::set_default_logger(new_logger).
 // For example, to replace it with a file logger.
@@ -121,52 +127,52 @@ SPDLOG_API spdlog::logger *default_logger_raw();
 
 SPDLOG_API void set_default_logger(std::shared_ptr<spdlog::logger> default_logger);
 
-template<typename... Args>
-inline void log(source_loc source, level::level_enum lvl, string_view_t fmt, const Args &... args)
+template<typename FormatString, typename... Args>
+inline void log(source_loc source, level::level_enum lvl, const FormatString &fmt, Args&&...args)
 {
-    default_logger_raw()->log(source, lvl, fmt, args...);
+    default_logger_raw()->log(source, lvl, fmt, std::forward<Args>(args)...);
 }
 
-template<typename... Args>
-inline void log(level::level_enum lvl, string_view_t fmt, const Args &... args)
+template<typename FormatString, typename... Args>
+inline void log(level::level_enum lvl, const FormatString &fmt, Args&&...args)
 {
-    default_logger_raw()->log(source_loc{}, lvl, fmt, args...);
+    default_logger_raw()->log(source_loc{}, lvl, fmt, std::forward<Args>(args)...);
 }
 
-template<typename... Args>
-inline void trace(string_view_t fmt, const Args &... args)
+template<typename FormatString, typename... Args>
+inline void trace(const FormatString &fmt, Args&&...args)
 {
-    default_logger_raw()->trace(fmt, args...);
+    default_logger_raw()->trace(fmt, std::forward<Args>(args)...);
 }
 
-template<typename... Args>
-inline void debug(string_view_t fmt, const Args &... args)
+template<typename FormatString, typename... Args>
+inline void debug(const FormatString &fmt, Args&&...args)
 {
-    default_logger_raw()->debug(fmt, args...);
+    default_logger_raw()->debug(fmt, std::forward<Args>(args)...);
 }
 
-template<typename... Args>
-inline void info(string_view_t fmt, const Args &... args)
+template<typename FormatString, typename... Args>
+inline void info(const FormatString &fmt, Args&&...args)
 {
-    default_logger_raw()->info(fmt, args...);
+    default_logger_raw()->info(fmt, std::forward<Args>(args)...);
 }
 
-template<typename... Args>
-inline void warn(string_view_t fmt, const Args &... args)
+template<typename FormatString, typename... Args>
+inline void warn(const FormatString &fmt, Args&&...args)
 {
-    default_logger_raw()->warn(fmt, args...);
+    default_logger_raw()->warn(fmt, std::forward<Args>(args)...);
 }
 
-template<typename... Args>
-inline void error(string_view_t fmt, const Args &... args)
+template<typename FormatString, typename... Args>
+inline void error(const FormatString &fmt, Args&&...args)
 {
-    default_logger_raw()->error(fmt, args...);
+    default_logger_raw()->error(fmt, std::forward<Args>(args)...);
 }
 
-template<typename... Args>
-inline void critical(string_view_t fmt, const Args &... args)
+template<typename FormatString, typename... Args>
+inline void critical(const FormatString &fmt, Args&&...args)
 {
-    default_logger_raw()->critical(fmt, args...);
+    default_logger_raw()->critical(fmt, std::forward<Args>(args)...);
 }
 
 template<typename T>
@@ -217,57 +223,6 @@ inline void critical(const T &msg)
     default_logger_raw()->critical(msg);
 }
 
-#ifdef SPDLOG_WCHAR_TO_UTF8_SUPPORT
-template<typename... Args>
-inline void log(source_loc source, level::level_enum lvl, wstring_view_t fmt, const Args &... args)
-{
-    default_logger_raw()->log(source, lvl, fmt, args...);
-}
-
-template<typename... Args>
-inline void log(level::level_enum lvl, wstring_view_t fmt, const Args &... args)
-{
-    default_logger_raw()->log(lvl, fmt, args...);
-}
-
-template<typename... Args>
-inline void trace(wstring_view_t fmt, const Args &... args)
-{
-    default_logger_raw()->trace(fmt, args...);
-}
-
-template<typename... Args>
-inline void debug(wstring_view_t fmt, const Args &... args)
-{
-    default_logger_raw()->debug(fmt, args...);
-}
-
-template<typename... Args>
-inline void info(wstring_view_t fmt, const Args &... args)
-{
-    default_logger_raw()->info(fmt, args...);
-}
-
-template<typename... Args>
-inline void warn(wstring_view_t fmt, const Args &... args)
-{
-    default_logger_raw()->warn(fmt, args...);
-}
-
-template<typename... Args>
-inline void error(wstring_view_t fmt, const Args &... args)
-{
-    default_logger_raw()->error(fmt, args...);
-}
-
-template<typename... Args>
-inline void critical(wstring_view_t fmt, const Args &... args)
-{
-    default_logger_raw()->critical(fmt, args...);
-}
-
-#endif // SPDLOG_WCHAR_TO_UTF8_SUPPORT
-
 } // namespace spdlog
 
 //

include/spdlog/stopwatch.h

@@ -0,0 +1,61 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+#include <spdlog/fmt/fmt.h>
+
+// Stopwatch support for spdlog  (using std::chrono::steady_clock).
+// Displays elapsed seconds since construction as double.
+//
+// Usage:
+//
+// spdlog::stopwatch sw;
+// ...
+// spdlog::debug("Elapsed: {} seconds", sw);    =>  "Elapsed 0.005116733 seconds"
+// spdlog::info("Elapsed: {:.6} seconds", sw);  =>  "Elapsed 0.005163 seconds"
+//
+//
+// If other units are needed (e.g. millis instead of double), include "fmt/chrono.h" and use "duration_cast<..>(sw.elapsed())":
+//
+// #include <spdlog/fmt/chrono.h>
+//..
+// using std::chrono::duration_cast;
+// using std::chrono::milliseconds;
+// spdlog::info("Elapsed {}", duration_cast<milliseconds>(sw.elapsed())); => "Elapsed 5ms"
+
+namespace spdlog {
+class stopwatch
+{
+    using clock = std::chrono::steady_clock;
+    std::chrono::time_point<clock> start_tp_;
+
+public:
+    stopwatch()
+        : start_tp_{clock::now()}
+    {}
+
+    std::chrono::duration<double> elapsed() const
+    {
+        return std::chrono::duration<double>(clock::now() - start_tp_);
+    }
+
+    void reset()
+    {
+        start_tp_ = clock ::now();
+    }
+};
+} // namespace spdlog
+
+// Support for fmt formatting  (e.g. "{:012.9}" or just "{}")
+namespace fmt {
+template<>
+struct formatter<spdlog::stopwatch> : formatter<double>
+{
+    template<typename FormatContext>
+    auto format(const spdlog::stopwatch &sw, FormatContext &ctx) -> decltype(ctx.out())
+    {
+        return formatter<double>::format(sw.elapsed().count(), ctx);
+    }
+};
+} // namespace fmt

include/spdlog/tweakme.h

@@ -58,6 +58,14 @@
 // #define SPDLOG_EOL ";-)\n"
 ///////////////////////////////////////////////////////////////////////////////
 
+///////////////////////////////////////////////////////////////////////////////
+// Uncomment to override default folder separators ("/" or "\\/" under
+// Linux/Windows). Each character in the string is treated as a different
+// separator.
+//
+// #define SPDLOG_FOLDER_SEPS "\\"
+///////////////////////////////////////////////////////////////////////////////
+
 ///////////////////////////////////////////////////////////////////////////////
 // Uncomment to use your own copy of the fmt library instead of spdlog's copy.
 // In this case spdlog will try to include <fmt/format.h> so set your -I flag

include/spdlog/version.h

@@ -4,7 +4,7 @@
 #pragma once
 
 #define SPDLOG_VER_MAJOR 1
-#define SPDLOG_VER_MINOR 6
-#define SPDLOG_VER_PATCH 0
+#define SPDLOG_VER_MINOR 8
+#define SPDLOG_VER_PATCH 5
 
 #define SPDLOG_VERSION (SPDLOG_VER_MAJOR * 10000 + SPDLOG_VER_MINOR * 100 + SPDLOG_VER_PATCH)

src/fmt.cpp

@@ -9,181 +9,95 @@
 #if !defined(SPDLOG_FMT_EXTERNAL)
 #include <spdlog/fmt/bundled/format-inl.h>
 
+
 FMT_BEGIN_NAMESPACE
-namespace internal {
+namespace detail {
 
-template<typename T>
-int format_float(char *buf, std::size_t size, const char *format, int precision, T value)
-{
-#ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
-    if (precision > 100000)
-        throw std::runtime_error("fuzz mode - avoid large allocation inside snprintf");
+template <typename T>
+int format_float(char* buf, std::size_t size, const char* format, int precision,
+                 T value) {
+#ifdef FMT_FUZZ
+  if (precision > 100000)
+    throw std::runtime_error(
+        "fuzz mode - avoid large allocation inside snprintf");
 #endif
-    // Suppress the warning about nonliteral format string.
-    int (*snprintf_ptr)(char *, size_t, const char *, ...) = FMT_SNPRINTF;
-    return precision < 0 ? snprintf_ptr(buf, size, format, value) : snprintf_ptr(buf, size, format, precision, value);
+  // Suppress the warning about nonliteral format string.
+  int (*snprintf_ptr)(char*, size_t, const char*, ...) = FMT_SNPRINTF;
+  return precision < 0 ? snprintf_ptr(buf, size, format, value)
+                       : snprintf_ptr(buf, size, format, precision, value);
 }
-struct sprintf_specs
-{
-    int precision;
-    char type;
-    bool alt : 1;
 
-    template<typename Char>
-    constexpr sprintf_specs(basic_format_specs<Char> specs)
-        : precision(specs.precision)
-        , type(specs.type)
-        , alt(specs.alt)
-    {}
+template FMT_API dragonbox::decimal_fp<float> dragonbox::to_decimal(float x)
+    FMT_NOEXCEPT;
+template FMT_API dragonbox::decimal_fp<double> dragonbox::to_decimal(double x)
+    FMT_NOEXCEPT;
 
-    constexpr bool has_precision() const
-    {
-        return precision >= 0;
-    }
-};
-
-// This is deprecated and is kept only to preserve ABI compatibility.
-template<typename Double>
-char *sprintf_format(Double value, internal::buffer<char> &buf, sprintf_specs specs)
-{
-    // Buffer capacity must be non-zero, otherwise MSVC's vsnprintf_s will fail.
-    FMT_ASSERT(buf.capacity() != 0, "empty buffer");
-
-    // Build format string.
-    enum
-    {
-        max_format_size = 10
-    }; // longest format: %#-*.*Lg
-    char format[max_format_size];
-    char *format_ptr = format;
-    *format_ptr++ = '%';
-    if (specs.alt || !specs.type)
-        *format_ptr++ = '#';
-    if (specs.precision >= 0)
-    {
-        *format_ptr++ = '.';
-        *format_ptr++ = '*';
-    }
-    if (std::is_same<Double, long double>::value)
-        *format_ptr++ = 'L';
-
-    char type = specs.type;
-
-    if (type == '%')
-        type = 'f';
-    else if (type == 0 || type == 'n')
-        type = 'g';
-#if FMT_MSC_VER
-    if (type == 'F')
-    {
-        // MSVC's printf doesn't support 'F'.
-        type = 'f';
-    }
-#endif
-    *format_ptr++ = type;
-    *format_ptr = '\0';
-
-    // Format using snprintf.
-    char *start = nullptr;
-    char *decimal_point_pos = nullptr;
-    for (;;)
-    {
-        std::size_t buffer_size = buf.capacity();
-        start = &buf[0];
-        int result = format_float(start, buffer_size, format, specs.precision, value);
-        if (result >= 0)
-        {
-            unsigned n = internal::to_unsigned(result);
-            if (n < buf.capacity())
-            {
-                // Find the decimal point.
-                auto p = buf.data(), end = p + n;
-                if (*p == '+' || *p == '-')
-                    ++p;
-                if (specs.type != 'a' && specs.type != 'A')
-                {
-                    while (p < end && *p >= '0' && *p <= '9')
-                        ++p;
-                    if (p < end && *p != 'e' && *p != 'E')
-                    {
-                        decimal_point_pos = p;
-                        if (!specs.type)
-                        {
-                            // Keep only one trailing zero after the decimal point.
-                            ++p;
-                            if (*p == '0')
-                                ++p;
-                            while (p != end && *p >= '1' && *p <= '9')
-                                ++p;
-                            char *where = p;
-                            while (p != end && *p == '0')
-                                ++p;
-                            if (p == end || *p < '0' || *p > '9')
-                            {
-                                if (p != end)
-                                    std::memmove(where, p, to_unsigned(end - p));
-                                n -= static_cast<unsigned>(p - where);
-                            }
-                        }
-                    }
-                }
-                buf.resize(n);
-                break; // The buffer is large enough - continue with formatting.
-            }
-            buf.reserve(n + 1);
-        }
-        else
-        {
-            // If result is negative we ask to increase the capacity by at least 1,
-            // but as std::vector, the buffer grows exponentially.
-            buf.reserve(buf.capacity() + 1);
-        }
-    }
-    return decimal_point_pos;
+// DEPRECATED! This function exists for ABI compatibility.
+template <typename Char>
+typename basic_format_context<std::back_insert_iterator<buffer<Char>>,
+                              Char>::iterator
+vformat_to(buffer<Char>& buf, basic_string_view<Char> format_str,
+           basic_format_args<basic_format_context<
+               std::back_insert_iterator<buffer<type_identity_t<Char>>>,
+               type_identity_t<Char>>>
+               args) {
+  using iterator = std::back_insert_iterator<buffer<char>>;
+  using context = basic_format_context<
+      std::back_insert_iterator<buffer<type_identity_t<Char>>>,
+      type_identity_t<Char>>;
+  auto out = iterator(buf);
+  format_handler<iterator, Char, context> h(out, format_str, args, {});
+  parse_format_string<false>(format_str, h);
+  return out;
 }
-} // namespace internal
+template basic_format_context<std::back_insert_iterator<buffer<char>>,
+                              char>::iterator
+vformat_to(buffer<char>&, string_view,
+           basic_format_args<basic_format_context<
+               std::back_insert_iterator<buffer<type_identity_t<char>>>,
+               type_identity_t<char>>>);
+}  // namespace detail
 
-template FMT_API char *internal::sprintf_format(double, internal::buffer<char> &, sprintf_specs);
-template FMT_API char *internal::sprintf_format(long double, internal::buffer<char> &, sprintf_specs);
-
-template struct FMT_INSTANTIATION_DEF_API internal::basic_data<void>;
+template struct FMT_INSTANTIATION_DEF_API detail::basic_data<void>;
 
 // Workaround a bug in MSVC2013 that prevents instantiation of format_float.
-int (*instantiate_format_float)(double, int, internal::float_specs, internal::buffer<char> &) = internal::format_float;
+int (*instantiate_format_float)(double, int, detail::float_specs,
+                                detail::buffer<char>&) = detail::format_float;
 
 #ifndef FMT_STATIC_THOUSANDS_SEPARATOR
-template FMT_API internal::locale_ref::locale_ref(const std::locale &loc);
-template FMT_API std::locale internal::locale_ref::get<std::locale>() const;
+template FMT_API detail::locale_ref::locale_ref(const std::locale& loc);
+template FMT_API std::locale detail::locale_ref::get<std::locale>() const;
 #endif
 
 // Explicit instantiations for char.
 
-template FMT_API std::string internal::grouping_impl<char>(locale_ref);
-template FMT_API char internal::thousands_sep_impl(locale_ref);
-template FMT_API char internal::decimal_point_impl(locale_ref);
+template FMT_API std::string detail::grouping_impl<char>(locale_ref);
+template FMT_API char detail::thousands_sep_impl(locale_ref);
+template FMT_API char detail::decimal_point_impl(locale_ref);
 
-template FMT_API void internal::buffer<char>::append(const char *, const char *);
+template FMT_API void detail::buffer<char>::append(const char*, const char*);
 
-template FMT_API void internal::arg_map<format_context>::init(const basic_format_args<format_context> &args);
+template FMT_API void detail::vformat_to(
+    detail::buffer<char>&, string_view,
+    basic_format_args<FMT_BUFFER_CONTEXT(char)>, detail::locale_ref);
 
-template FMT_API std::string internal::vformat<char>(string_view, basic_format_args<format_context>);
-
-template FMT_API format_context::iterator internal::vformat_to(internal::buffer<char> &, string_view, basic_format_args<format_context>);
-
-template FMT_API int internal::snprintf_float(double, int, internal::float_specs, internal::buffer<char> &);
-template FMT_API int internal::snprintf_float(long double, int, internal::float_specs, internal::buffer<char> &);
-template FMT_API int internal::format_float(double, int, internal::float_specs, internal::buffer<char> &);
-template FMT_API int internal::format_float(long double, int, internal::float_specs, internal::buffer<char> &);
+template FMT_API int detail::snprintf_float(double, int, detail::float_specs,
+                                            detail::buffer<char>&);
+template FMT_API int detail::snprintf_float(long double, int,
+                                            detail::float_specs,
+                                            detail::buffer<char>&);
+template FMT_API int detail::format_float(double, int, detail::float_specs,
+                                          detail::buffer<char>&);
+template FMT_API int detail::format_float(long double, int, detail::float_specs,
+                                          detail::buffer<char>&);
 
 // Explicit instantiations for wchar_t.
 
-template FMT_API std::string internal::grouping_impl<wchar_t>(locale_ref);
-template FMT_API wchar_t internal::thousands_sep_impl(locale_ref);
-template FMT_API wchar_t internal::decimal_point_impl(locale_ref);
+template FMT_API std::string detail::grouping_impl<wchar_t>(locale_ref);
+template FMT_API wchar_t detail::thousands_sep_impl(locale_ref);
+template FMT_API wchar_t detail::decimal_point_impl(locale_ref);
 
-template FMT_API void internal::buffer<wchar_t>::append(const wchar_t *, const wchar_t *);
-
-template FMT_API std::wstring internal::vformat<wchar_t>(wstring_view, basic_format_args<wformat_context>);
+template FMT_API void detail::buffer<wchar_t>::append(const wchar_t*,
+                                                      const wchar_t*);
 FMT_END_NAMESPACE
-
-#endif // !SPDLOG_FMT_EXTERNAL
+#endif // !SPDLOG_FMT_EXTERNAL

tests/CMakeLists.txt

@@ -1,5 +1,4 @@
-cmake_minimum_required(VERSION 3.2)
-
+cmake_minimum_required(VERSION 3.10)
 project(spdlog_utests CXX)
 
 if(NOT TARGET spdlog)
@@ -33,7 +32,8 @@ set(SPDLOG_UTESTS_SOURCES
     test_backtrace.cpp
     test_create_dir.cpp
     test_cfg.cpp
-    test_time_point.cpp)
+    test_time_point.cpp
+    test_stopwatch.cpp)
 
 if(NOT SPDLOG_NO_EXCEPTIONS)
     list(APPEND SPDLOG_UTESTS_SOURCES test_errors.cpp)

tests/test_async.cpp

@@ -3,6 +3,8 @@
 #include "spdlog/sinks/basic_file_sink.h"
 #include "test_sink.h"
 
+#define TEST_FILENAME "test_logs/async_test.log"
+
 TEST_CASE("basic async test ", "[async]")
 {
     auto test_sink = std::make_shared<spdlog::sinks::test_sink_mt>();
@@ -87,7 +89,7 @@ TEST_CASE("async periodic flush", "[async]")
     auto test_sink = std::static_pointer_cast<spdlog::sinks::test_sink_mt>(logger->sinks()[0]);
 
     spdlog::flush_every(std::chrono::seconds(1));
-    std::this_thread::sleep_for(std::chrono::milliseconds(1100));
+    std::this_thread::sleep_for(std::chrono::milliseconds(1700));
     REQUIRE(test_sink->flush_counter() == 1);
     spdlog::flush_every(std::chrono::seconds(0));
     spdlog::drop_all();
@@ -149,7 +151,7 @@ TEST_CASE("to_file", "[async]")
     prepare_logdir();
     size_t messages = 1024;
     size_t tp_threads = 1;
-    std::string filename = "test_logs/async_test.log";
+    spdlog::filename_t filename = SPDLOG_FILENAME_T(TEST_FILENAME);
     {
         auto file_sink = std::make_shared<spdlog::sinks::basic_file_sink_mt>(filename, true);
         auto tp = std::make_shared<spdlog::details::thread_pool>(messages, tp_threads);
@@ -161,8 +163,8 @@ TEST_CASE("to_file", "[async]")
         }
     }
 
-    require_message_count(filename, messages);
-    auto contents = file_contents(filename);
+    require_message_count(TEST_FILENAME, messages);
+    auto contents = file_contents(TEST_FILENAME);
     using spdlog::details::os::default_eol;
     REQUIRE(ends_with(contents, fmt::format("Hello message #1023{}", default_eol)));
 }
@@ -172,7 +174,7 @@ TEST_CASE("to_file multi-workers", "[async]")
     prepare_logdir();
     size_t messages = 1024 * 10;
     size_t tp_threads = 10;
-    std::string filename = "test_logs/async_test.log";
+    spdlog::filename_t filename = SPDLOG_FILENAME_T(TEST_FILENAME);
     {
         auto file_sink = std::make_shared<spdlog::sinks::basic_file_sink_mt>(filename, true);
         auto tp = std::make_shared<spdlog::details::thread_pool>(messages, tp_threads);
@@ -184,5 +186,5 @@ TEST_CASE("to_file multi-workers", "[async]")
         }
     }
 
-    require_message_count(filename, messages);
+    require_message_count(TEST_FILENAME, messages);
 }

tests/test_cfg.cpp

@@ -1,3 +1,4 @@
+
 #include "includes.h"
 #include "test_sink.h"
 
@@ -41,21 +42,23 @@ TEST_CASE("argv2", "[cfg]")
     auto l1 = spdlog::create<test_sink_st>("l1");
     REQUIRE(l1->level() == spdlog::level::warn);
     REQUIRE(spdlog::default_logger()->level() == spdlog::level::trace);
-    spdlog::set_level(spdlog::level::info);
 }
 
 TEST_CASE("argv3", "[cfg]")
 {
+    spdlog::set_level(spdlog::level::trace);
+
     spdlog::drop("l1");
-    const char *argv[] = {"ignore", "SPDLOG_LEVEL="};
+    const char *argv[] = {"ignore", "SPDLOG_LEVEL=junk_name=warn"};
     load_argv_levels(2, argv);
     auto l1 = spdlog::create<test_sink_st>("l1");
-    REQUIRE(l1->level() == spdlog::level::info);
-    REQUIRE(spdlog::default_logger()->level() == spdlog::level::info);
+    REQUIRE(l1->level() == spdlog::level::trace);
+    REQUIRE(spdlog::default_logger()->level() == spdlog::level::trace);
 }
 
 TEST_CASE("argv4", "[cfg]")
 {
+    spdlog::set_level(spdlog::level::info);
     spdlog::drop("l1");
     const char *argv[] = {"ignore", "SPDLOG_LEVEL=junk"};
     load_argv_levels(2, argv);
@@ -65,6 +68,7 @@ TEST_CASE("argv4", "[cfg]")
 
 TEST_CASE("argv5", "[cfg]")
 {
+    spdlog::set_level(spdlog::level::info);
     spdlog::drop("l1");
     const char *argv[] = {"ignore", "ignore", "SPDLOG_LEVEL=l1=warn,trace"};
     load_argv_levels(3, argv);
@@ -91,3 +95,89 @@ TEST_CASE("argv7", "[cfg]")
     REQUIRE(spdlog::default_logger()->level() == spdlog::level::err);
     spdlog::set_level(spdlog::level::info);
 }
+
+TEST_CASE("level-not-set-test1", "[cfg]")
+{
+    spdlog::drop("l1");
+    const char *argv[] = {"ignore", ""};
+    load_argv_levels(2, argv);
+    auto l1 = spdlog::create<spdlog::sinks::test_sink_st>("l1");
+    l1->set_level(spdlog::level::trace);
+    REQUIRE(l1->level() == spdlog::level::trace);
+    REQUIRE(spdlog::default_logger()->level() == spdlog::level::info);
+}
+
+TEST_CASE("level-not-set-test2", "[cfg]")
+{
+    spdlog::drop("l1");
+    spdlog::drop("l2");
+    const char *argv[] = {"ignore", "SPDLOG_LEVEL=l1=trace"};
+
+    auto l1 = spdlog::create<spdlog::sinks::test_sink_st>("l1");
+    l1->set_level(spdlog::level::warn);
+    auto l2 = spdlog::create<spdlog::sinks::test_sink_st>("l2");
+    l2->set_level(spdlog::level::warn);
+
+    load_argv_levels(2, argv);
+
+    REQUIRE(l1->level() == spdlog::level::trace);
+    REQUIRE(l2->level() == spdlog::level::warn);
+    REQUIRE(spdlog::default_logger()->level() == spdlog::level::info);
+}
+
+TEST_CASE("level-not-set-test3", "[cfg]")
+{
+    spdlog::drop("l1");
+    spdlog::drop("l2");
+    const char *argv[] = {"ignore", "SPDLOG_LEVEL=l1=trace"};
+
+    load_argv_levels(2, argv);
+
+    auto l1 = spdlog::create<spdlog::sinks::test_sink_st>("l1");
+    auto l2 = spdlog::create<spdlog::sinks::test_sink_st>("l2");
+
+    REQUIRE(l1->level() == spdlog::level::trace);
+    REQUIRE(l2->level() == spdlog::level::info);
+    REQUIRE(spdlog::default_logger()->level() == spdlog::level::info);
+}
+
+TEST_CASE("level-not-set-test4", "[cfg]")
+{
+    spdlog::drop("l1");
+    spdlog::drop("l2");
+    const char *argv[] = {"ignore", "SPDLOG_LEVEL=l1=trace,warn"};
+
+    load_argv_levels(2, argv);
+
+    auto l1 = spdlog::create<spdlog::sinks::test_sink_st>("l1");
+    auto l2 = spdlog::create<spdlog::sinks::test_sink_st>("l2");
+
+    REQUIRE(l1->level() == spdlog::level::trace);
+    REQUIRE(l2->level() == spdlog::level::warn);
+    REQUIRE(spdlog::default_logger()->level() == spdlog::level::warn);
+}
+
+TEST_CASE("level-not-set-test5", "[cfg]")
+{
+    spdlog::drop("l1");
+    spdlog::drop("l2");
+    const char *argv[] = {"ignore", "SPDLOG_LEVEL=l1=junk,warn"};
+
+    load_argv_levels(2, argv);
+
+    auto l1 = spdlog::create<spdlog::sinks::test_sink_st>("l1");
+    auto l2 = spdlog::create<spdlog::sinks::test_sink_st>("l2");
+
+    REQUIRE(l1->level() == spdlog::level::warn);
+    REQUIRE(l2->level() == spdlog::level::warn);
+    REQUIRE(spdlog::default_logger()->level() == spdlog::level::warn);
+}
+
+TEST_CASE("restore-to-default", "[cfg]")
+{
+    spdlog::drop("l1");
+    spdlog::drop("l2");
+    const char *argv[] = {"ignore", "SPDLOG_LEVEL=info"};
+    load_argv_levels(2, argv);
+    REQUIRE(spdlog::default_logger()->level() == spdlog::level::info);
+}

tests/test_create_dir.cpp

@@ -6,7 +6,7 @@
 using spdlog::details::os::create_dir;
 using spdlog::details::os::path_exists;
 
-bool try_create_dir(const char *path, const char *normalized_path)
+bool try_create_dir(const spdlog::filename_t &path, const spdlog::filename_t &normalized_path)
 {
     auto rv = create_dir(path);
     REQUIRE(rv == true);
@@ -17,24 +17,24 @@ TEST_CASE("create_dir", "[create_dir]")
 {
     prepare_logdir();
 
-    REQUIRE(try_create_dir("test_logs/dir1/dir1", "test_logs/dir1/dir1"));
-    REQUIRE(try_create_dir("test_logs/dir1/dir1", "test_logs/dir1/dir1")); // test existing
-    REQUIRE(try_create_dir("test_logs/dir1///dir2//", "test_logs/dir1/dir2"));
-    REQUIRE(try_create_dir("./test_logs/dir1/dir3", "test_logs/dir1/dir3"));
-    REQUIRE(try_create_dir("test_logs/../test_logs/dir1/dir4", "test_logs/dir1/dir4"));
+    REQUIRE(try_create_dir(SPDLOG_FILENAME_T("test_logs/dir1/dir1"), SPDLOG_FILENAME_T("test_logs/dir1/dir1")));
+    REQUIRE(try_create_dir(SPDLOG_FILENAME_T("test_logs/dir1/dir1"), SPDLOG_FILENAME_T("test_logs/dir1/dir1"))); // test existing
+    REQUIRE(try_create_dir(SPDLOG_FILENAME_T("test_logs/dir1///dir2//"), SPDLOG_FILENAME_T("test_logs/dir1/dir2")));
+    REQUIRE(try_create_dir(SPDLOG_FILENAME_T("./test_logs/dir1/dir3"), SPDLOG_FILENAME_T("test_logs/dir1/dir3")));
+    REQUIRE(try_create_dir(SPDLOG_FILENAME_T("test_logs/../test_logs/dir1/dir4"), SPDLOG_FILENAME_T("test_logs/dir1/dir4")));
 
 #ifdef WIN32
     // test backslash folder separator
-    REQUIRE(try_create_dir("test_logs\\dir1\\dir222", "test_logs\\dir1\\dir222"));
-    REQUIRE(try_create_dir("test_logs\\dir1\\dir223\\", "test_logs\\dir1\\dir223\\"));
-    REQUIRE(try_create_dir(".\\test_logs\\dir1\\dir2\\dir99\\..\\dir23", "test_logs\\dir1\\dir2\\dir23"));
-    REQUIRE(try_create_dir("test_logs\\..\\test_logs\\dir1\\dir5", "test_logs\\dir1\\dir5"));
+    REQUIRE(try_create_dir(SPDLOG_FILENAME_T("test_logs\\dir1\\dir222"), SPDLOG_FILENAME_T("test_logs\\dir1\\dir222")));
+    REQUIRE(try_create_dir(SPDLOG_FILENAME_T("test_logs\\dir1\\dir223\\"), SPDLOG_FILENAME_T("test_logs\\dir1\\dir223\\")));
+    REQUIRE(try_create_dir(SPDLOG_FILENAME_T(".\\test_logs\\dir1\\dir2\\dir99\\..\\dir23"), SPDLOG_FILENAME_T("test_logs\\dir1\\dir2\\dir23")));
+    REQUIRE(try_create_dir(SPDLOG_FILENAME_T("test_logs\\..\\test_logs\\dir1\\dir5"), SPDLOG_FILENAME_T("test_logs\\dir1\\dir5")));
 #endif
 }
 
 TEST_CASE("create_invalid_dir", "[create_dir]")
 {
-    REQUIRE(create_dir("") == false);
+    REQUIRE(create_dir(SPDLOG_FILENAME_T("")) == false);
     REQUIRE(create_dir(spdlog::filename_t{}) == false);
 #ifdef __linux__
     REQUIRE(create_dir("/proc/spdlog-utest") == false);
@@ -44,37 +44,31 @@ TEST_CASE("create_invalid_dir", "[create_dir]")
 TEST_CASE("dir_name", "[create_dir]")
 {
     using spdlog::details::os::dir_name;
-    REQUIRE(dir_name("").empty());
-    REQUIRE(dir_name("dir").empty());
+    REQUIRE(dir_name(SPDLOG_FILENAME_T("")).empty());
+    REQUIRE(dir_name(SPDLOG_FILENAME_T("dir")).empty());
 
 #ifdef WIN32
-    REQUIRE(dir_name(R"(dir\)") == "dir");
-    REQUIRE(dir_name(R"(dir\\\)") == R"(dir\\)");
-    REQUIRE(dir_name(R"(dir\file)") == "dir");
-    REQUIRE(dir_name(R"(dir/file)") == "dir");
-    REQUIRE(dir_name(R"(dir\file.txt)") == "dir");
-    REQUIRE(dir_name(R"(dir/file)") == "dir");
-    REQUIRE(dir_name(R"(dir\file.txt\)") == R"(dir\file.txt)");
-    REQUIRE(dir_name(R"(dir/file.txt/)") == R"(dir\file.txt)");
-    REQUIRE(dir_name(R"(\dir\file.txt)") == R"(\dir)");
-    REQUIRE(dir_name(R"(/dir/file.txt)") == R"(\dir)");
-    REQUIRE(dir_name(R"(\\dir\file.txt)") == R"(\\dir)");
-    REQUIRE(dir_name(R"(//dir/file.txt)") == R"(\\dir)");
-    REQUIRE(dir_name(R"(..\file.txt)") == "..");
-    REQUIRE(dir_name(R"(../file.txt)") == "..");
-    REQUIRE(dir_name(R"(.\file.txt)") == ".");
-    REQUIRE(dir_name(R"(./file.txt)") == ".");
-    REQUIRE(dir_name(R"(c:\\a\b\c\d\file.txt)") == R"(c:\\a\b\c\d)");
-    REQUIRE(dir_name(R"(c://a/b/c/d/file.txt)") == R"(c:\\a\b\c\d)");
-#else
-    REQUIRE(dir_name("dir/") == "dir");
-    REQUIRE(dir_name("dir///") == "dir//");
-    REQUIRE(dir_name("dir/file") == "dir");
-    REQUIRE(dir_name("dir/file.txt") == "dir");
-    REQUIRE(dir_name("dir/file.txt/") == "dir/file.txt");
-    REQUIRE(dir_name("/dir/file.txt") == "/dir");
-    REQUIRE(dir_name("//dir/file.txt") == "//dir");
-    REQUIRE(dir_name("../file.txt") == "..");
-    REQUIRE(dir_name("./file.txt") == ".");
+    REQUIRE(dir_name(SPDLOG_FILENAME_T(R"(dir\)")) == SPDLOG_FILENAME_T("dir"));
+    REQUIRE(dir_name(SPDLOG_FILENAME_T(R"(dir\\\)")) == SPDLOG_FILENAME_T(R"(dir\\)"));
+    REQUIRE(dir_name(SPDLOG_FILENAME_T(R"(dir\file)")) == SPDLOG_FILENAME_T("dir"));
+    REQUIRE(dir_name(SPDLOG_FILENAME_T(R"(dir/file)")) == SPDLOG_FILENAME_T("dir"));
+    REQUIRE(dir_name(SPDLOG_FILENAME_T(R"(dir\file.txt)")) == SPDLOG_FILENAME_T("dir"));
+    REQUIRE(dir_name(SPDLOG_FILENAME_T(R"(dir/file)")) == SPDLOG_FILENAME_T("dir"));
+    REQUIRE(dir_name(SPDLOG_FILENAME_T(R"(dir\file.txt\)")) == SPDLOG_FILENAME_T(R"(dir\file.txt)"));
+    REQUIRE(dir_name(SPDLOG_FILENAME_T(R"(\dir\file.txt)")) == SPDLOG_FILENAME_T(R"(\dir)"));
+    REQUIRE(dir_name(SPDLOG_FILENAME_T(R"(\\dir\file.txt)")) == SPDLOG_FILENAME_T(R"(\\dir)"));
+    REQUIRE(dir_name(SPDLOG_FILENAME_T(R"(..\file.txt)")) == SPDLOG_FILENAME_T(".."));
+    REQUIRE(dir_name(SPDLOG_FILENAME_T(R"(.\file.txt)")) == SPDLOG_FILENAME_T("."));
+    REQUIRE(dir_name(SPDLOG_FILENAME_T(R"(c:\\a\b\c\d\file.txt)")) == SPDLOG_FILENAME_T(R"(c:\\a\b\c\d)"));
+    REQUIRE(dir_name(SPDLOG_FILENAME_T(R"(c://a/b/c/d/file.txt)")) == SPDLOG_FILENAME_T(R"(c://a/b/c/d)"));
 #endif
+    REQUIRE(dir_name(SPDLOG_FILENAME_T("dir/")) == SPDLOG_FILENAME_T("dir"));
+    REQUIRE(dir_name(SPDLOG_FILENAME_T("dir///")) == SPDLOG_FILENAME_T("dir//"));
+    REQUIRE(dir_name(SPDLOG_FILENAME_T("dir/file")) == SPDLOG_FILENAME_T("dir"));
+    REQUIRE(dir_name(SPDLOG_FILENAME_T("dir/file.txt")) == SPDLOG_FILENAME_T("dir"));
+    REQUIRE(dir_name(SPDLOG_FILENAME_T("dir/file.txt/")) == SPDLOG_FILENAME_T("dir/file.txt"));
+    REQUIRE(dir_name(SPDLOG_FILENAME_T("/dir/file.txt")) == SPDLOG_FILENAME_T("/dir"));
+    REQUIRE(dir_name(SPDLOG_FILENAME_T("//dir/file.txt")) == SPDLOG_FILENAME_T("//dir"));
+    REQUIRE(dir_name(SPDLOG_FILENAME_T("../file.txt")) == SPDLOG_FILENAME_T(".."));
+    REQUIRE(dir_name(SPDLOG_FILENAME_T("./file.txt")) == SPDLOG_FILENAME_T("."));
 }

tests/test_daily_logger.cpp

@@ -3,6 +3,8 @@
  */
 #include "includes.h"
 
+using filename_memory_buf_t = fmt::basic_memory_buffer<spdlog::filename_t::value_type, 250>;
+
 TEST_CASE("daily_logger with dateonly calculator", "[daily_logger]")
 {
     using sink_type = spdlog::sinks::daily_file_sink<std::mutex, spdlog::sinks::daily_filename_calculator>;
@@ -10,10 +12,10 @@ TEST_CASE("daily_logger with dateonly calculator", "[daily_logger]")
     prepare_logdir();
 
     // calculate filename (time based)
-    std::string basename = "test_logs/daily_dateonly";
+    spdlog::filename_t basename = SPDLOG_FILENAME_T("test_logs/daily_dateonly");
     std::tm tm = spdlog::details::os::localtime();
-    spdlog::memory_buf_t w;
-    fmt::format_to(w, "{}_{:04d}-{:02d}-{:02d}", basename, tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday);
+    filename_memory_buf_t w;
+    fmt::format_to(w, SPDLOG_FILENAME_T("{}_{:04d}-{:02d}-{:02d}"), basename, tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday);
 
     auto logger = spdlog::create<sink_type>("logger", basename, 0, 0);
     for (int i = 0; i < 10; ++i)
@@ -23,7 +25,13 @@ TEST_CASE("daily_logger with dateonly calculator", "[daily_logger]")
     }
     logger->flush();
 
+#ifdef SPDLOG_WCHAR_FILENAMES
+    spdlog::memory_buf_t buf;
+    spdlog::details::os::wstr_to_utf8buf(fmt::to_string(w), buf);
+    auto filename = fmt::to_string(buf);
+#else
     auto filename = fmt::to_string(w);
+#endif
     require_message_count(filename, 10);
 }
 
@@ -31,8 +39,8 @@ struct custom_daily_file_name_calculator
 {
     static spdlog::filename_t calc_filename(const spdlog::filename_t &basename, const tm &now_tm)
     {
-        spdlog::memory_buf_t w;
-        fmt::format_to(w, "{}{:04d}{:02d}{:02d}", basename, now_tm.tm_year + 1900, now_tm.tm_mon + 1, now_tm.tm_mday);
+        filename_memory_buf_t w;
+        fmt::format_to(w, SPDLOG_FILENAME_T("{}{:04d}{:02d}{:02d}"), basename, now_tm.tm_year + 1900, now_tm.tm_mon + 1, now_tm.tm_mday);
         return fmt::to_string(w);
     }
 };
@@ -44,10 +52,10 @@ TEST_CASE("daily_logger with custom calculator", "[daily_logger]")
     prepare_logdir();
 
     // calculate filename (time based)
-    std::string basename = "test_logs/daily_dateonly";
+    spdlog::filename_t basename = SPDLOG_FILENAME_T("test_logs/daily_dateonly");
     std::tm tm = spdlog::details::os::localtime();
-    spdlog::memory_buf_t w;
-    fmt::format_to(w, "{}{:04d}{:02d}{:02d}", basename, tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday);
+    filename_memory_buf_t w;
+    fmt::format_to(w, SPDLOG_FILENAME_T("{}{:04d}{:02d}{:02d}"), basename, tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday);
 
     auto logger = spdlog::create<sink_type>("logger", basename, 0, 0);
     for (int i = 0; i < 10; ++i)
@@ -57,7 +65,13 @@ TEST_CASE("daily_logger with custom calculator", "[daily_logger]")
 
     logger->flush();
 
+#ifdef SPDLOG_WCHAR_FILENAMES
+    spdlog::memory_buf_t buf;
+    spdlog::details::os::wstr_to_utf8buf(fmt::to_string(w), buf);
+    auto filename = fmt::to_string(buf);
+#else
     auto filename = fmt::to_string(w);
+#endif
     require_message_count(filename, 10);
 }
 
@@ -67,20 +81,20 @@ TEST_CASE("daily_logger with custom calculator", "[daily_logger]")
 
 TEST_CASE("rotating_file_sink::calc_filename1", "[rotating_file_sink]]")
 {
-    auto filename = spdlog::sinks::rotating_file_sink_st::calc_filename("rotated.txt", 3);
-    REQUIRE(filename == "rotated.3.txt");
+    auto filename = spdlog::sinks::rotating_file_sink_st::calc_filename(SPDLOG_FILENAME_T("rotated.txt"), 3);
+    REQUIRE(filename == SPDLOG_FILENAME_T("rotated.3.txt"));
 }
 
 TEST_CASE("rotating_file_sink::calc_filename2", "[rotating_file_sink]]")
 {
-    auto filename = spdlog::sinks::rotating_file_sink_st::calc_filename("rotated", 3);
-    REQUIRE(filename == "rotated.3");
+    auto filename = spdlog::sinks::rotating_file_sink_st::calc_filename(SPDLOG_FILENAME_T("rotated"), 3);
+    REQUIRE(filename == SPDLOG_FILENAME_T("rotated.3"));
 }
 
 TEST_CASE("rotating_file_sink::calc_filename3", "[rotating_file_sink]]")
 {
-    auto filename = spdlog::sinks::rotating_file_sink_st::calc_filename("rotated.txt", 0);
-    REQUIRE(filename == "rotated.txt");
+    auto filename = spdlog::sinks::rotating_file_sink_st::calc_filename(SPDLOG_FILENAME_T("rotated.txt"), 0);
+    REQUIRE(filename == SPDLOG_FILENAME_T("rotated.txt"));
 }
 
 // regex supported only from gcc 4.9 and above
@@ -91,10 +105,10 @@ TEST_CASE("rotating_file_sink::calc_filename3", "[rotating_file_sink]]")
 TEST_CASE("daily_file_sink::daily_filename_calculator", "[daily_file_sink]]")
 {
     // daily_YYYY-MM-DD_hh-mm.txt
-    auto filename = spdlog::sinks::daily_filename_calculator::calc_filename("daily.txt", spdlog::details::os::localtime());
+    auto filename = spdlog::sinks::daily_filename_calculator::calc_filename(SPDLOG_FILENAME_T("daily.txt"), spdlog::details::os::localtime());
     // date regex based on https://www.regular-expressions.info/dates.html
-    std::regex re(R"(^daily_(19|20)\d\d-(0[1-9]|1[012])-(0[1-9]|[12][0-9]|3[01])\.txt$)");
-    std::smatch match;
+    std::basic_regex<spdlog::filename_t::value_type> re(SPDLOG_FILENAME_T(R"(^daily_(19|20)\d\d-(0[1-9]|1[012])-(0[1-9]|[12][0-9]|3[01])\.txt$)"));
+    std::match_results<spdlog::filename_t::const_iterator> match;
     REQUIRE(std::regex_match(filename, match, re));
 }
 #endif
@@ -116,7 +130,7 @@ static void test_rotate(int days_to_run, uint16_t max_days, uint16_t expected_n_
 
     prepare_logdir();
 
-    std::string basename = "test_logs/daily_rotate.txt";
+    spdlog::filename_t basename = SPDLOG_FILENAME_T("test_logs/daily_rotate.txt");
     daily_file_sink_st sink{basename, 2, 30, true, max_days};
 
     // simulate messages with 24 intervals

tests/test_errors.cpp

@@ -5,6 +5,9 @@
 
 #include <iostream>
 
+#define SIMPLE_LOG "test_logs/simple_log.txt"
+#define SIMPLE_ASYNC_LOG "test_logs/simple_async_log.txt"
+
 class failing_sink : public spdlog::sinks::base_sink<std::mutex>
 {
 protected:
@@ -22,7 +25,7 @@ protected:
 TEST_CASE("default_error_handler", "[errors]]")
 {
     prepare_logdir();
-    std::string filename = "test_logs/simple_log.txt";
+    spdlog::filename_t filename = SPDLOG_FILENAME_T(SIMPLE_LOG);
 
     auto logger = spdlog::create<spdlog::sinks::basic_file_sink_mt>("test-error", filename, true);
     logger->set_pattern("%v");
@@ -31,8 +34,8 @@ TEST_CASE("default_error_handler", "[errors]]")
     logger->flush();
 
     using spdlog::details::os::default_eol;
-    REQUIRE(file_contents(filename) == fmt::format("Test message 2{}", default_eol));
-    REQUIRE(count_lines(filename) == 1);
+    REQUIRE(file_contents(SIMPLE_LOG) == fmt::format("Test message 2{}", default_eol));
+    REQUIRE(count_lines(SIMPLE_LOG) == 1);
 }
 
 struct custom_ex
@@ -40,7 +43,7 @@ struct custom_ex
 TEST_CASE("custom_error_handler", "[errors]]")
 {
     prepare_logdir();
-    std::string filename = "test_logs/simple_log.txt";
+    spdlog::filename_t filename = SPDLOG_FILENAME_T(SIMPLE_LOG);
     auto logger = spdlog::create<spdlog::sinks::basic_file_sink_mt>("logger", filename, true);
     logger->flush_on(spdlog::level::info);
     logger->set_error_handler([=](const std::string &) { throw custom_ex(); });
@@ -48,7 +51,7 @@ TEST_CASE("custom_error_handler", "[errors]]")
 
     REQUIRE_THROWS_AS(logger->info("Bad format msg {} {}", "xxx"), custom_ex);
     logger->info("Good message #2");
-    require_message_count(filename, 2);
+    require_message_count(SIMPLE_LOG, 2);
 }
 
 TEST_CASE("default_error_handler2", "[errors]]")
@@ -72,7 +75,7 @@ TEST_CASE("async_error_handler", "[errors]]")
     prepare_logdir();
     std::string err_msg("log failed with some msg");
 
-    std::string filename = "test_logs/simple_async_log.txt";
+    spdlog::filename_t filename = SPDLOG_FILENAME_T(SIMPLE_ASYNC_LOG);
     {
         spdlog::init_thread_pool(128, 1);
         auto logger = spdlog::create_async<spdlog::sinks::basic_file_sink_mt>("logger", filename, true);
@@ -90,7 +93,7 @@ TEST_CASE("async_error_handler", "[errors]]")
         spdlog::drop("logger"); // force logger to drain the queue and shutdown
     }
     spdlog::init_thread_pool(128, 1);
-    require_message_count(filename, 2);
+    require_message_count(SIMPLE_ASYNC_LOG, 2);
     REQUIRE(file_contents("test_logs/custom_err.txt") == err_msg);
 }
 
@@ -100,7 +103,7 @@ TEST_CASE("async_error_handler2", "[errors]]")
     prepare_logdir();
     std::string err_msg("This is async handler error message");
     {
-        spdlog::details::os::create_dir("test_logs");
+        spdlog::details::os::create_dir(SPDLOG_FILENAME_T("test_logs"));
         spdlog::init_thread_pool(128, 1);
         auto logger = spdlog::create_async<failing_sink>("failed_logger");
         logger->set_error_handler([=](const std::string &) {

tests/test_eventlog.cpp

@@ -24,20 +24,20 @@ static void test_single_print(std::function<void(std::string const &)> do_log, s
                 REQUIRE(CloseEventLog(handle_));
             }
         }
-    } event_log{::OpenEventLog(nullptr, TEST_SOURCE)};
+    } event_log{::OpenEventLogA(nullptr, TEST_SOURCE)};
 
     REQUIRE(event_log.handle_);
 
     DWORD read_bytes{}, size_needed{};
     auto ok =
-        ::ReadEventLog(event_log.handle_, EVENTLOG_SEQUENTIAL_READ | EVENTLOG_BACKWARDS_READ, 0, &read_bytes, 0, &read_bytes, &size_needed);
+        ::ReadEventLogA(event_log.handle_, EVENTLOG_SEQUENTIAL_READ | EVENTLOG_BACKWARDS_READ, 0, &read_bytes, 0, &read_bytes, &size_needed);
     REQUIRE(!ok);
     REQUIRE(::GetLastError() == ERROR_INSUFFICIENT_BUFFER);
 
     std::vector<char> record_buffer(size_needed);
     PEVENTLOGRECORD record = (PEVENTLOGRECORD)record_buffer.data();
 
-    ok = ::ReadEventLog(
+    ok = ::ReadEventLogA(
         event_log.handle_, EVENTLOG_SEQUENTIAL_READ | EVENTLOG_BACKWARDS_READ, 0, record, size_needed, &read_bytes, &size_needed);
     REQUIRE(ok);
 

tests/test_file_helper.cpp

@@ -3,6 +3,8 @@
  */
 #include "includes.h"
 
+#define TEST_FILENAME "test_logs/file_helper_test.txt"
+
 using spdlog::details::file_helper;
 
 static void write_with_helper(file_helper &helper, size_t howmany)
@@ -18,7 +20,7 @@ TEST_CASE("file_helper_filename", "[file_helper::filename()]]")
     prepare_logdir();
 
     file_helper helper;
-    std::string target_filename = "test_logs/file_helper_test.txt";
+    spdlog::filename_t target_filename = SPDLOG_FILENAME_T(TEST_FILENAME);
     helper.open(target_filename);
     REQUIRE(helper.filename() == target_filename);
 }
@@ -26,7 +28,7 @@ TEST_CASE("file_helper_filename", "[file_helper::filename()]]")
 TEST_CASE("file_helper_size", "[file_helper::size()]]")
 {
     prepare_logdir();
-    std::string target_filename = "test_logs/file_helper_test.txt";
+    spdlog::filename_t target_filename = SPDLOG_FILENAME_T(TEST_FILENAME);
     size_t expected_size = 123;
     {
         file_helper helper;
@@ -34,13 +36,13 @@ TEST_CASE("file_helper_size", "[file_helper::size()]]")
         write_with_helper(helper, expected_size);
         REQUIRE(static_cast<size_t>(helper.size()) == expected_size);
     }
-    REQUIRE(get_filesize(target_filename) == expected_size);
+    REQUIRE(get_filesize(TEST_FILENAME) == expected_size);
 }
 
 TEST_CASE("file_helper_reopen", "[file_helper::reopen()]]")
 {
     prepare_logdir();
-    std::string target_filename = "test_logs/file_helper_test.txt";
+    spdlog::filename_t target_filename = SPDLOG_FILENAME_T(TEST_FILENAME);
     file_helper helper;
     helper.open(target_filename);
     write_with_helper(helper, 12);
@@ -52,7 +54,7 @@ TEST_CASE("file_helper_reopen", "[file_helper::reopen()]]")
 TEST_CASE("file_helper_reopen2", "[file_helper::reopen(false)]]")
 {
     prepare_logdir();
-    std::string target_filename = "test_logs/file_helper_test.txt";
+    spdlog::filename_t target_filename = SPDLOG_FILENAME_T(TEST_FILENAME);
     size_t expected_size = 14;
     file_helper helper;
     helper.open(target_filename);
@@ -62,16 +64,12 @@ TEST_CASE("file_helper_reopen2", "[file_helper::reopen(false)]]")
     REQUIRE(helper.size() == expected_size);
 }
 
-static void test_split_ext(const char *fname, const char *expect_base, const char *expect_ext)
+static void test_split_ext(const spdlog::filename_t::value_type *fname, const spdlog::filename_t::value_type *expect_base, const spdlog::filename_t::value_type *expect_ext)
 {
     spdlog::filename_t filename(fname);
     spdlog::filename_t expected_base(expect_base);
     spdlog::filename_t expected_ext(expect_ext);
 
-#ifdef _WIN32 // replace folder sep
-    std::replace(filename.begin(), filename.end(), '/', '\\');
-    std::replace(expected_base.begin(), expected_base.end(), '/', '\\');
-#endif
     spdlog::filename_t basename;
     spdlog::filename_t ext;
     std::tie(basename, ext) = file_helper::split_by_extension(filename);
@@ -81,22 +79,22 @@ static void test_split_ext(const char *fname, const char *expect_base, const cha
 
 TEST_CASE("file_helper_split_by_extension", "[file_helper::split_by_extension()]]")
 {
-    test_split_ext("mylog.txt", "mylog", ".txt");
-    test_split_ext(".mylog.txt", ".mylog", ".txt");
-    test_split_ext(".mylog", ".mylog", "");
-    test_split_ext("/aaa/bb.d/mylog", "/aaa/bb.d/mylog", "");
-    test_split_ext("/aaa/bb.d/mylog.txt", "/aaa/bb.d/mylog", ".txt");
-    test_split_ext("aaa/bbb/ccc/mylog.txt", "aaa/bbb/ccc/mylog", ".txt");
-    test_split_ext("aaa/bbb/ccc/mylog.", "aaa/bbb/ccc/mylog.", "");
-    test_split_ext("aaa/bbb/ccc/.mylog.txt", "aaa/bbb/ccc/.mylog", ".txt");
-    test_split_ext("/aaa/bbb/ccc/mylog.txt", "/aaa/bbb/ccc/mylog", ".txt");
-    test_split_ext("/aaa/bbb/ccc/.mylog", "/aaa/bbb/ccc/.mylog", "");
-    test_split_ext("../mylog.txt", "../mylog", ".txt");
-    test_split_ext(".././mylog.txt", ".././mylog", ".txt");
-    test_split_ext(".././mylog.txt/xxx", ".././mylog.txt/xxx", "");
-    test_split_ext("/mylog.txt", "/mylog", ".txt");
-    test_split_ext("//mylog.txt", "//mylog", ".txt");
-    test_split_ext("", "", "");
-    test_split_ext(".", ".", "");
-    test_split_ext("..txt", ".", ".txt");
+    test_split_ext(SPDLOG_FILENAME_T("mylog.txt"), SPDLOG_FILENAME_T("mylog"), SPDLOG_FILENAME_T(".txt"));
+    test_split_ext(SPDLOG_FILENAME_T(".mylog.txt"), SPDLOG_FILENAME_T(".mylog"), SPDLOG_FILENAME_T(".txt"));
+    test_split_ext(SPDLOG_FILENAME_T(".mylog"), SPDLOG_FILENAME_T(".mylog"), SPDLOG_FILENAME_T(""));
+    test_split_ext(SPDLOG_FILENAME_T("/aaa/bb.d/mylog"), SPDLOG_FILENAME_T("/aaa/bb.d/mylog"), SPDLOG_FILENAME_T(""));
+    test_split_ext(SPDLOG_FILENAME_T("/aaa/bb.d/mylog.txt"), SPDLOG_FILENAME_T("/aaa/bb.d/mylog"), SPDLOG_FILENAME_T(".txt"));
+    test_split_ext(SPDLOG_FILENAME_T("aaa/bbb/ccc/mylog.txt"), SPDLOG_FILENAME_T("aaa/bbb/ccc/mylog"), SPDLOG_FILENAME_T(".txt"));
+    test_split_ext(SPDLOG_FILENAME_T("aaa/bbb/ccc/mylog."), SPDLOG_FILENAME_T("aaa/bbb/ccc/mylog."), SPDLOG_FILENAME_T(""));
+    test_split_ext(SPDLOG_FILENAME_T("aaa/bbb/ccc/.mylog.txt"), SPDLOG_FILENAME_T("aaa/bbb/ccc/.mylog"), SPDLOG_FILENAME_T(".txt"));
+    test_split_ext(SPDLOG_FILENAME_T("/aaa/bbb/ccc/mylog.txt"), SPDLOG_FILENAME_T("/aaa/bbb/ccc/mylog"), SPDLOG_FILENAME_T(".txt"));
+    test_split_ext(SPDLOG_FILENAME_T("/aaa/bbb/ccc/.mylog"), SPDLOG_FILENAME_T("/aaa/bbb/ccc/.mylog"), SPDLOG_FILENAME_T(""));
+    test_split_ext(SPDLOG_FILENAME_T("../mylog.txt"), SPDLOG_FILENAME_T("../mylog"), SPDLOG_FILENAME_T(".txt"));
+    test_split_ext(SPDLOG_FILENAME_T(".././mylog.txt"), SPDLOG_FILENAME_T(".././mylog"), SPDLOG_FILENAME_T(".txt"));
+    test_split_ext(SPDLOG_FILENAME_T(".././mylog.txt/xxx"), SPDLOG_FILENAME_T(".././mylog.txt/xxx"), SPDLOG_FILENAME_T(""));
+    test_split_ext(SPDLOG_FILENAME_T("/mylog.txt"), SPDLOG_FILENAME_T("/mylog"), SPDLOG_FILENAME_T(".txt"));
+    test_split_ext(SPDLOG_FILENAME_T("//mylog.txt"), SPDLOG_FILENAME_T("//mylog"), SPDLOG_FILENAME_T(".txt"));
+    test_split_ext(SPDLOG_FILENAME_T(""), SPDLOG_FILENAME_T(""), SPDLOG_FILENAME_T(""));
+    test_split_ext(SPDLOG_FILENAME_T("."), SPDLOG_FILENAME_T("."), SPDLOG_FILENAME_T(""));
+    test_split_ext(SPDLOG_FILENAME_T("..txt"), SPDLOG_FILENAME_T("."), SPDLOG_FILENAME_T(".txt"));
 }

tests/test_file_logging.cpp

@@ -3,10 +3,13 @@
  */
 #include "includes.h"
 
+#define SIMPLE_LOG "test_logs/simple_log"
+#define ROTATING_LOG "test_logs/rotating_log"
+
 TEST_CASE("simple_file_logger", "[simple_logger]]")
 {
     prepare_logdir();
-    std::string filename = "test_logs/simple_log";
+    spdlog::filename_t filename = SPDLOG_FILENAME_T(SIMPLE_LOG);
 
     auto logger = spdlog::create<spdlog::sinks::basic_file_sink_mt>("logger", filename);
     logger->set_pattern("%v");
@@ -15,29 +18,29 @@ TEST_CASE("simple_file_logger", "[simple_logger]]")
     logger->info("Test message {}", 2);
 
     logger->flush();
-    require_message_count(filename, 2);
+    require_message_count(SIMPLE_LOG, 2);
     using spdlog::details::os::default_eol;
-    REQUIRE(file_contents(filename) == fmt::format("Test message 1{}Test message 2{}", default_eol, default_eol));
+    REQUIRE(file_contents(SIMPLE_LOG) == fmt::format("Test message 1{}Test message 2{}", default_eol, default_eol));
 }
 
 TEST_CASE("flush_on", "[flush_on]]")
 {
     prepare_logdir();
-    std::string filename = "test_logs/simple_log";
+    spdlog::filename_t filename = SPDLOG_FILENAME_T(SIMPLE_LOG);
 
     auto logger = spdlog::create<spdlog::sinks::basic_file_sink_mt>("logger", filename);
     logger->set_pattern("%v");
     logger->set_level(spdlog::level::trace);
     logger->flush_on(spdlog::level::info);
     logger->trace("Should not be flushed");
-    REQUIRE(count_lines(filename) == 0);
+    REQUIRE(count_lines(SIMPLE_LOG) == 0);
 
     logger->info("Test message {}", 1);
     logger->info("Test message {}", 2);
 
-    require_message_count(filename, 3);
+    require_message_count(SIMPLE_LOG, 3);
     using spdlog::details::os::default_eol;
-    REQUIRE(file_contents(filename) ==
+    REQUIRE(file_contents(SIMPLE_LOG) ==
             fmt::format("Should not be flushed{}Test message 1{}Test message 2{}", default_eol, default_eol, default_eol));
 }
 
@@ -45,7 +48,7 @@ TEST_CASE("rotating_file_logger1", "[rotating_logger]]")
 {
     prepare_logdir();
     size_t max_size = 1024 * 10;
-    std::string basename = "test_logs/rotating_log";
+    spdlog::filename_t basename = SPDLOG_FILENAME_T(ROTATING_LOG);
     auto logger = spdlog::rotating_logger_mt("logger", basename, max_size, 0);
 
     for (int i = 0; i < 10; ++i)
@@ -54,14 +57,14 @@ TEST_CASE("rotating_file_logger1", "[rotating_logger]]")
     }
 
     logger->flush();
-    require_message_count(basename, 10);
+    require_message_count(ROTATING_LOG, 10);
 }
 
 TEST_CASE("rotating_file_logger2", "[rotating_logger]]")
 {
     prepare_logdir();
     size_t max_size = 1024 * 10;
-    std::string basename = "test_logs/rotating_log";
+    spdlog::filename_t basename = SPDLOG_FILENAME_T(ROTATING_LOG);
 
     {
         // make an initial logger to create the first output file
@@ -83,7 +86,7 @@ TEST_CASE("rotating_file_logger2", "[rotating_logger]]")
 
     logger->flush();
 
-    require_message_count(basename, 10);
+    require_message_count(ROTATING_LOG, 10);
 
     for (int i = 0; i < 1000; i++)
     {
@@ -92,7 +95,6 @@ TEST_CASE("rotating_file_logger2", "[rotating_logger]]")
     }
 
     logger->flush();
-    REQUIRE(get_filesize(basename) <= max_size);
-    auto filename1 = basename + ".1";
-    REQUIRE(get_filesize(filename1) <= max_size);
+    REQUIRE(get_filesize(ROTATING_LOG) <= max_size);
+    REQUIRE(get_filesize(ROTATING_LOG ".1") <= max_size);
 }

tests/test_macros.cpp

@@ -8,11 +8,13 @@
 #error "Invalid SPDLOG_ACTIVE_LEVEL in test. Should be SPDLOG_LEVEL_DEBUG"
 #endif
 
+#define TEST_FILENAME "test_logs/simple_log"
+
 TEST_CASE("debug and trace w/o format string", "[macros]]")
 {
 
     prepare_logdir();
-    std::string filename = "test_logs/simple_log";
+    spdlog::filename_t filename = SPDLOG_FILENAME_T(TEST_FILENAME);
 
     auto logger = spdlog::create<spdlog::sinks::basic_file_sink_mt>("logger", filename);
     logger->set_pattern("%v");
@@ -23,8 +25,8 @@ TEST_CASE("debug and trace w/o format string", "[macros]]")
     logger->flush();
 
     using spdlog::details::os::default_eol;
-    REQUIRE(ends_with(file_contents(filename), fmt::format("Test message 2{}", default_eol)));
-    REQUIRE(count_lines(filename) == 1);
+    REQUIRE(ends_with(file_contents(TEST_FILENAME), fmt::format("Test message 2{}", default_eol)));
+    REQUIRE(count_lines(TEST_FILENAME) == 1);
 
     spdlog::set_default_logger(logger);
 
@@ -32,8 +34,8 @@ TEST_CASE("debug and trace w/o format string", "[macros]]")
     SPDLOG_DEBUG("Test message {}", 4);
     logger->flush();
 
-    require_message_count(filename, 2);
-    REQUIRE(ends_with(file_contents(filename), fmt::format("Test message 4{}", default_eol)));
+    require_message_count(TEST_FILENAME, 2);
+    REQUIRE(ends_with(file_contents(TEST_FILENAME), fmt::format("Test message 4{}", default_eol)));
 }
 
 TEST_CASE("disable param evaluation", "[macros]")

tests/test_misc.cpp

@@ -55,6 +55,14 @@ TEST_CASE("level_to_string_view", "[convert_to_string_view")
     REQUIRE(spdlog::level::to_string_view(spdlog::level::off) == "off");
 }
 
+TEST_CASE("set_level_to_string_view", "[set_string_view")
+{
+    spdlog::level::set_string_view(spdlog::level::info, "INF");
+    REQUIRE(spdlog::level::to_string_view(spdlog::level::info) == "INF");
+    spdlog::level::set_string_view(spdlog::level::info, "info"); // set it back
+    REQUIRE(spdlog::level::to_string_view(spdlog::level::info) == "info");
+}
+
 TEST_CASE("to_short_c_str", "[convert_to_short_c_str]")
 {
     REQUIRE(std::string(spdlog::level::to_short_c_str(spdlog::level::trace)) == "T");

tests/test_mpmc_q.cpp

@@ -10,7 +10,7 @@ static milliseconds millis_from(const test_clock::time_point &tp0)
 TEST_CASE("dequeue-empty-nowait", "[mpmc_blocking_q]")
 {
     size_t q_size = 100;
-    milliseconds tolerance_wait(10);
+    milliseconds tolerance_wait(20);
     spdlog::details::mpmc_blocking_queue<int> q(q_size);
     int popped_item = 0;
 

tests/test_pattern_formatter.cpp

@@ -5,7 +5,7 @@ using spdlog::memory_buf_t;
 
 // log to str and return it
 template<typename... Args>
-static std::string log_to_str(const std::string &msg, const Args &... args)
+static std::string log_to_str(const std::string &msg, const Args &...args)
 {
     std::ostringstream oss;
     auto oss_sink = std::make_shared<spdlog::sinks::ostream_sink_mt>(oss);
@@ -227,7 +227,7 @@ TEST_CASE("paddinng_truncate", "[pattern_formatter]")
     REQUIRE(log_to_str("123456", "%0!v", spdlog::pattern_time_type::local, "\n") == "\n");
 }
 
-TEST_CASE("paddinng_truncate_funcname", "[pattern_formatter]")
+TEST_CASE("padding_truncate_funcname", "[pattern_formatter]")
 {
     spdlog::sinks::test_sink_st test_sink;
 
@@ -237,13 +237,28 @@ TEST_CASE("paddinng_truncate_funcname", "[pattern_formatter]")
 
     spdlog::details::log_msg msg1{spdlog::source_loc{"ignored", 1, "func"}, "test_logger", spdlog::level::info, "message"};
     test_sink.log(msg1);
+    REQUIRE(test_sink.lines()[0] == "message [ func]");
 
     spdlog::details::log_msg msg2{spdlog::source_loc{"ignored", 1, "function"}, "test_logger", spdlog::level::info, "message"};
     test_sink.log(msg2);
+    REQUIRE(test_sink.lines()[1] == "message [funct]");
+}
 
-    auto lines = test_sink.lines();
-    REQUIRE(lines[0] == "message [ func]");
-    REQUIRE(lines[1] == "message [funct]");
+TEST_CASE("padding_funcname", "[pattern_formatter]")
+{
+    spdlog::sinks::test_sink_st test_sink;
+
+    const char *pattern = "%v [%10!]";
+    auto formatter = std::unique_ptr<spdlog::formatter>(new spdlog::pattern_formatter(pattern));
+    test_sink.set_formatter(std::move(formatter));
+
+    spdlog::details::log_msg msg1{spdlog::source_loc{"ignored", 1, "func"}, "test_logger", spdlog::level::info, "message"};
+    test_sink.log(msg1);
+    REQUIRE(test_sink.lines()[0] == "message [      func]");
+
+    spdlog::details::log_msg msg2{spdlog::source_loc{"ignored", 1, "func567890123"}, "test_logger", spdlog::level::info, "message"};
+    test_sink.log(msg2);
+    REQUIRE(test_sink.lines()[1] == "message [func567890123]");
 }
 
 TEST_CASE("clone-default-formatter", "[pattern_formatter]")
@@ -357,7 +372,7 @@ TEST_CASE("clone-custom_formatter", "[pattern_formatter]")
 //
 
 #ifdef _WIN32
-static const char *const test_path = "\\a\\b\\myfile.cpp";
+static const char *const test_path = "\\a\\b\\c/myfile.cpp";
 #else
 static const char *const test_path = "/a/b//myfile.cpp";
 #endif

tests/test_registry.cpp

@@ -103,7 +103,7 @@ TEST_CASE("disable automatic registration", "[registry]")
     spdlog::set_level(log_level);
     // but disable automatic registration
     spdlog::set_automatic_registration(false);
-    auto logger1 = spdlog::create<spdlog::sinks::daily_file_sink_st>(tested_logger_name, "filename", 11, 59);
+    auto logger1 = spdlog::create<spdlog::sinks::daily_file_sink_st>(tested_logger_name, SPDLOG_FILENAME_T("filename"), 11, 59);
     auto logger2 = spdlog::create_async<spdlog::sinks::stdout_color_sink_mt>(tested_logger_name2);
     // loggers should not be part of the registry
     REQUIRE_FALSE(spdlog::get(tested_logger_name));

tests/test_stopwatch.cpp

@@ -0,0 +1,35 @@
+#include "includes.h"
+#include "test_sink.h"
+#include "spdlog/stopwatch.h"
+
+TEST_CASE("stopwatch1", "[stopwatch]")
+{
+    using std::chrono::milliseconds;
+    milliseconds wait_ms(250);
+    milliseconds tolerance_ms(250);
+
+    spdlog::stopwatch sw;
+    std::this_thread::sleep_for(wait_ms);
+    REQUIRE(sw.elapsed() >= wait_ms);
+    REQUIRE(sw.elapsed() <= wait_ms + tolerance_ms);
+}
+
+TEST_CASE("stopwatch2", "[stopwatch]")
+{
+    using spdlog::sinks::test_sink_st;
+
+    std::chrono::duration<double> wait_duration(0.250);
+    std::chrono::duration<double> tolerance_duration(0.250);
+
+    auto test_sink = std::make_shared<test_sink_st>();
+
+    spdlog::stopwatch sw;
+    spdlog::logger logger("test-stopwatch", test_sink);
+    logger.set_pattern("%v");
+    std::this_thread::sleep_for(wait_duration);
+    logger.info("{}", sw);
+    auto val = std::stod(test_sink->lines()[0]);
+
+    REQUIRE(val >= wait_duration.count());
+    REQUIRE(val <= (wait_duration + tolerance_duration).count());
+}

tests/utils.cpp

@@ -1,6 +1,8 @@
 #include "includes.h"
 
-#ifndef _WIN32
+#ifdef _WIN32
+#include <Windows.h>
+#else
 #include <sys/types.h>
 #include <dirent.h>
 #endif
@@ -82,7 +84,7 @@ bool ends_with(std::string const &value, std::string const &ending)
 std::size_t count_files(const std::string &folder)
 {
     size_t counter = 0;
-    WIN32_FIND_DATA ffd;
+    WIN32_FIND_DATAA ffd;
 
     // Start iterating over the files in the folder directory.
     HANDLE hFind = ::FindFirstFileA((folder + "\\*").c_str(), &ffd);
@@ -92,7 +94,7 @@ std::size_t count_files(const std::string &folder)
         {
             if (ffd.cFileName[0] != '.')
                 counter++;
-        } while (::FindNextFile(hFind, &ffd) != 0);
+        } while (::FindNextFileA(hFind, &ffd) != 0);
         ::FindClose(hFind);
     }
     else