fmt: update bundled fmt to 3.0.1 (7fa8f8f)

Signed-off-by: Damien Zammit <damien@zamaudio.com>

include/spdlog/fmt/bundled/time.h

@@ -0,0 +1,53 @@
+/*
+ Formatting library for C++ - time formatting
+
+ Copyright (c) 2012 - 2016, Victor Zverovich
+ All rights reserved.
+
+ For the license information refer to format.h.
+ */
+
+#ifndef FMT_TIME_H_
+#define FMT_TIME_H_
+
+#include "format.h"
+#include <ctime>
+
+namespace fmt {
+template <typename ArgFormatter>
+void format(BasicFormatter<char, ArgFormatter> &f,
+            const char *&format_str, const std::tm &tm) {
+  if (*format_str == ':')
+    ++format_str;
+  const char *end = format_str;
+  while (*end && *end != '}')
+    ++end;
+  if (*end != '}')
+    FMT_THROW(FormatError("missing '}' in format string"));
+  internal::MemoryBuffer<char, internal::INLINE_BUFFER_SIZE> format;
+  format.append(format_str, end + 1);
+  format[format.size() - 1] = '\0';
+  Buffer<char> &buffer = f.writer().buffer();
+  std::size_t start = buffer.size();
+  for (;;) {
+    std::size_t size = buffer.capacity() - start;
+    std::size_t count = std::strftime(&buffer[start], size, &format[0], &tm);
+    if (count != 0) {
+      buffer.resize(start + count);
+      break;
+    }
+    if (size >= format.size() * 256) {
+      // If the buffer is 256 times larger than the format string, assume
+      // that `strftime` gives an empty result. There doesn't seem to be a
+      // better way to distinguish the two cases:
+      // https://github.com/fmtlib/fmt/issues/367
+      break;
+    }
+    const std::size_t MIN_GROWTH = 10;
+    buffer.reserve(buffer.capacity() + (size > MIN_GROWTH ? size : MIN_GROWTH));
+  }
+  format_str = end + 1;
+}
+}
+
+#endif  // FMT_TIME_H_