Version 1.6.0

What's new

• Load log levels from environment variable SPDLOG_LEVEL :

#include "spdlog/cfg/env.h"
...
spdlog::cfg::load_env_levels(); 

$ # set log level to debug
$  SPDLOG_LEVEL=debug && ./example

$ # set to info except for mylogger which is set to trace:
$ SPDLOG_LEVEL=info,mylogger=trace  && ./example

$ # turn off all logging except for mylogger which is set to debug::
$ SPDLOG_LEVEL=off,mylogger=debug && ./example

• Load log levels from argv (e.g. ./example SPDLOG_LEVEL=debug):

#include "spdlog/cfg/argv.h"
...
spdlog::cfg::load_argv_levels(argc, argv);

• New windows eventlog sink . Thanks @ban-dana (#1418).

• New tcp sink that sends log messages in tcp to a remote server. Thanks @Proheeler (#1426).

• Extend spdlog with your own flags in the log pattern. See wiki for details.

• Support for building spdlog as dll under windows. Thanks vejmartin (#1467, 3b73278, 5b3a183).

• Bump the bundled fmt version to 6.2.0 .

Fixes and Improvements

• Prevent race condition when SPDLOG_PREVENT_CHILD_FD is defined. Thanks @dominicpoeschko (#1423).

• Fix race condition in the filename() function in the file sinks. Thanks @tt4g (#1430, #1431).

• Fix ansicolor_sink::set_color(..) - can cause memory violation if user provides a custom color code that points to stack memory (#1540, 0b36d4e). Thanks @caizongchao for reporting.

• Fix potential buffer overflow in color_sinks if creating multiple color sinks in the same logger and one of them has a pattern without color flags (#1452, 64de880). Thanks @dominicpoeschko for reporting.

• Optimize cases when string_view is passed to the logger to avoid unnecessary fmt::format. Thanks dominicpoeschko (#1424) .

• Support for max files in daily logger - delete oldest files after creating the daily file. Thanks @ruoshui1314 (#1394).

• Fix deprecated warning with C++14 and external fmt lib (#1439). Thanks @ClausKlein for reporting.

• Optimize colos sinks to use std::array instead of map to find color codes (695912c, 4b7c059). Thanks @qis for the suggestion.

• Fix Win32 event log sink compilation. Thanks @Crunkle (#1444).

• Don't include windows.h in common.h. Thanks @ghost (#1453).

• Resolve erroneous clang-tidy warning about using a moved from pointer. Thanks @ruffel (#1457).

• Fixed numerous clang-tidy warnings.

• Added options to to_hex to output hex like hexdump. Thanks @ngugcx (#1472).

• Fix Windows setenv check. Thanks @Crunkle (#1475).

• Removed the 'SPDLOG_NO_NAME` macro in tweakme.h and cmake.

• Added a forward declaration header spdlog\fwd.h . Thanks @horenmar for the suggestion (#1481).

• Moved throw to dedicated function to optimize compile-time and runtime-performance. Thanks @horenmar for the suggestion (#1483).

• Fix a build issue when SPDLOG_PREVENT_CHILD_FD is defined. Thanks @Naios (#1487).

• Fix issue with using external fmt (#1480). Thanks @nalinigans for reporting.

• Minor performance optimizations in pattern formatter (ca9c83f, 76389e0, 7766bc2, d38bd13)

• Fixed on Android compilation #1527. Thanks @Bizyroth for reporting.

• Add log function to the logger API to allow logging with custom timepoint. #1521 - Thanks @ron003 .

• Fix missing exported symbol when building spdlog.dll in windows (#1535, 348c438). Thanks @plmzod for reporting.

• Dropped meson support.

• Fix typos and tabs in the code. Thanks @waywardmonkeys (#1536) .

• CMake: Fix GNUInstallDirs include location Thanks @vitlav (#1407).

• CMake: workaround for Unknown extension ".c" for file issue . Thanks @niamster (#1442).

• CMake: Support CPack RPM generation. Thanks @tcraigtyler (#1451).

• CMake: Disabled extra warnings generation by default. Use SPDLOG_BUILD_WARNINGS=ON to enable again. Thanks @Glamhoth (#1503 02802af, 6440733, 1f7f1c1)

• CMake: Support for precompiled headers with SPDLOG_ENABLE_PCH flag. Thanks @OlivierLDff (#1484).

• CMake: Add /WX MSVC compiler option for only if mscv compiler is used. Thanks @trondhe (#1495).

• CMake: Set minimum version of fmt to 5.3.0. Thanks @Montellese (#1525).

• CMake: Fix tabs, whitespaces and eol. Thanks @waywardmonkeys (#1537).

• Tests: removed duplicate entry for count_lines(). Thanks @emmenlau (#1417).

• Tests: don't run spdlog-utests and spdlog-utests-ho in parallel. Thanks @tt4g (#1421).

• Tests: Enable running the tests against an installed copy of spdlog. Thanks @mr-c (#1422).

• Tests: Support empty SPDLOG_EOL. Thanks @emmenlau (#1414).

• README: add conda as a supported package manager . Thanks @avrahamshukron (#1473).

• README: Replace yaourt with yay` pacakge manage for archlinux. Thanks @zyansheep (#1494).

Version 1.5.0

New features

• Added ringbuffer sink. Thanks @eudoxos (#1307).
• Auto create the required logging directories if they do not exist (9b7812a).
• Update bundled fmt to version 6.1.2.
• Added the optional ! modifier to truncate the result if the field size exceeds the specified width (see wiki for details).

Fixes and improvements

• Fix build failure on clang 7 with libc++. Thanks @jktjkt (a03f9eb).
• Fix some spelling errors. Thanks @flopp .
• Fix - compilation when using external fmt library. Thanks @dvhwgumby for reporting (#1273).
• Fix location of CMake config info. Thanks @dvhwgumby for reporting (#1274)
• Fix missing include (9a68bd8).
• CMake code duplication improvement. Thanks @bencsikandrei (#1283)
• CMake improvments in tests . Thanks @Andrei-Florin BENCSIK (2cc620e)
• Remove unused variable. Thanks @masmullin2000 (#1285)
• Fix tests to Use _FILE_OFFSET_BITS=64 when building on Linux 32-bit systems. Thanks @yipdw (#1288).
• Improve systemd journald support. Thanks @jktjkt (#1292).
• Improve log macros. Thanks @pck (#1294).
• Removed lazy argument evaluation from macros (#163).
• Some micro optimizations (79468cf, 3ee4f28, bf40855).
• Correctly guard SetHandleInformation API call to better support compiling for UWP. Thanks @sylveon (#1296).
• Exclude from compilation prevent_child_fd() if SPDLOG_PREVENT_CHILD_FD not defined (57085c8)
• CMake - Added tweakme options to CMakeLists.txt (18edb8b).
• Removed SPDLOG_NO_DATETIME option.
• Fix meson tests build . Thanks vedranmiletic fore reporting (#1295, c081919, 4a4f13b, 436ce16).
• Use #include" <spdlog/.*> instead of spdlog/.* across the codebase. Thanks @reddwarf69 (#1304).
• Fix struct tm doesn't have tm_gmtoff in ISO C. Thanks @LanceSun (ff3e6c7, #1306)
• Always cache gmt offset (de2c07a).
• Optimize backtracer operator= (255f7f2).
• Fix some clang-tidy warnings (93008b2, bff8572, 3999613).
• Fix compiler error in os-inl.h min/max on Windows (#1302).
• Remove redundant semicolon. Thanks @inhzus (#1311).
• Fix compiler warnings. Thanks @0x8000-0000 (#1331).
• Fix missing include header in `spdlog/sinks/daily_file_sink.h. Thanks @afoolsbag for reporting (#1332).
• Fix elapsed time larger than 6 digits ignores alignment width. Thanks @ivan236634452 for reporting (#1327).
• Set version for shared library in meson build. Thanks @lgbaldoni (#1337).
• Improved dist_sink ctor. Thanks @mmakhalaf for reporting (#1298).
• Fix #1325. Added SPDLOG_FMT_EXTERNAL_HO option. Thanks @steffenb7333 for reporting.
• Fix #1340 (missing include). Thanks @jeanga for reporting.
• Fix compile on Win10 with Cygwin. Thanks @frfrankkopp and @tt4g (#1347).
• Fixed #1348. Thanks @ficzerepeti for reporting.
• CMakeLists.txt allow overriding the cpp standard to higher than 11
• Fix a small problem in the basic example. Thanks @mike239x (#1367).
• Fix invalid meson option. Thanks @segfault-magnet (#1370).
• meson: add fallback to fmt dependency #1378. Thanks @iDanko
• Update docs: spdlog now available in conan center, bincrafters repo is deprecated #1387. Thanks @gocarlos .

Version 1.4.2

Fix some issues discovered by users:

• Set additional CPACK variables for RPM generator (#1246). Thanks @tcraigtyler.
• Fix compile when SPDLOG_WCHAR_FILENAMES is defined (#1249 ).
• Fix stdout color sink under Windows to better handle cases when no console available (#1250).
• Fix windows compile error where std::max is overriden by a macro. (#1251, #1252). Thanks @bsergean.
• CMakeLists.txt: Moved the installed lib to CMAKE_INSTALL_LIBDIR (#1253). Thanks @DasRoteSkelett.
• CMakeLists.txt: Fixed pkg-config generation (cf2bf48, fb70eca). Thanks @SammyEnigma.

Version 1.4.1

Fix few issues discovered by users of 1.4.0

• Added pkgconfig file to CMake install - Thanks @orbea for reporting and fixing (#1237 #1238).
• Fix regression in wchar support under windows. Thanks @Bak-Jin-Hyeong for reporting and fixing (#1239 #1240).
• CMake: Do not install bundled fmt if SPDLOG_FMT_EXTERNAL is defined. Thanks @orbea (#1241).

Version 1.4.0

Improvements

• spdlog can now be compiled as a static or shared lib (thanks @DavidZemon for the help).
  Using the compiled lib improves greatly compile times when using spdlog and is very recommended.

  $ cd spdlog && mkdir build && cd build
  # Build is static lib (pass -DSPDLOG_BUILD_SHARED=ON for building as shared lib)
  $ cmake .. && make -j

• Upgraded to the latest and greatest fmt library version 6.0.0. Thanks @tgpfeiffer (and to @vitaut for fmt!).
• Support for -fno-exceptions (disabled by default). Enabling this will replace all throw() statements in spdlog with std::abort(). To enable, pass -DSPDLOG_NO_EXCEPTIONS=ON to CMake before building spdlog.
• support for building spdlog with meson. Thanks @mensinda
• Backtrace support - store debug/trace messages in a ring buffer to display later on demand. Very useful (thanks @MathijsV for the idea):

spdlog::enable_backtrace(32); // create ring buffer with capacity of 32  messages
// or my_logger->enable_backtrace(32)..
for(int i = 0; i < 100; i++)
{
  spdlog::debug("Backtrace message {}", i); // not logged yet.. 
}
// e.g. if some error happened:
spdlog::dump_backtrace(); // log them now! show the last 32 messages
// or my_logger->dump_backtrace(32)..

• Systemd support. Thanks @WarShoe (#1027)
• Support for cleaning old files in daily_logger.
• Numerous CMake build improvements. Thanks @DavidZemon , @jktjkt , @ksergey , @mnemotic , @cneumann , @dpacbach , @FrancoisChabot , @myd7349 , @matt77hias
• Better support for various Unix BSDs (DragonFly, NetBSD, FreeBSD, OpenBSD). Thanks @jbeich (#1234)
• Provide source location support for systemd sink. Thanks @jbelloncastro (#1122)
• Added fmt::(w)string_view support. Thanks @matt77hias (#1139)
• Add option to force color output without TTY . Thanks @psalz (#1175)
• Add more overloads to spdlog::log and spdlog::logger::log. Thanks @sylveon (@1169)
• Add public API spdlog::initialize_logger for create loggers manually. Thanks @tt4g (#1035)
• Expose should_do_colors_ in ansicolor_sink.h. Thanks Florian Wörter (#1022)
• Add tweak support for user short level names. Thanks @MFornander (#996)
• Add method to filesinks to return filename. Thanks @markniebur (#978)
• rotating_sink: Add option to rotate on open. Thanks @pwm1234 (#958)
• Allow filename/line number at all levels. Add function name %! support. Thanks @possiblyhuman (#956)
• New dups_filter sink -duplicate message removal sink. It will skip a message if previous one is identical and less than "max_skip_duration" old.
• New '%o', '%i', '%u', '%O' format flags - Display elapsed time in mills/micros/nanos/seconds since previous message.
• Some minor pattern formatter performance improvements.

Fixes

• Fix Wundef in os-inl.h. Thanks @AMS21 (#1189)
• Fix use of old style cast in os-inl.h. Thanks @AMS21 (#1164)
• Prevent NEAR and FAR macro definitions from leaking on Windows platforms. Thanks @PeterTh (#1142)
• Fix syslog output. Thanks @mattiasj-axis (#1140)
• Fix msg.time in daily_file_sink. Thanks @s-shin (#1129)
• Fix missing include for null_mutex in rotating_file_sink.h. Thanks @casperevan (#1120)
• Fix warning: redundant move in return statement. Thanks @MarkKoester (#1119)
• Fix use of incomplete type in stdout sinks. Thanks @DanielChabrowski (#1118)
• Fix deprecation warnings in filename_to_str and improve performance of wbuf_to_utf8buf. Thanks @sylveon (#1127)
• Update README.md. Thanks @martinkrammer (#1057)
• Remove extra semicolon. Thanks @Jerry-Ma (#1202)
• Fix unexpected log macro expansion. Thanks @db-panda (#1055)
• Namespace qualify stat functions. Thanks @p-po (#1045)
• Fix typo in Android logger. Thanks @romainthomas (#994)
• Remove unnecessary log function. Thanks @DanielChabrowski (#988)
• Allow custom formatter in sink's ctor. Thanks @DanielChabrowski (#986)
• Fix shadowed parameter. Thanks @ZGCDDoo (#984)
• Update log_msg.h. Thanks @scribam (#969)
• Fix #benchmark link error. Thanks @myd7349 (#962)
• Fix typo in file_helper.h. Thanks @brridder (#955)

Version 1.3.1

Fix few issues found by 1.3.0 users:

• Fix google benchmark link error when compiling the bechmarks. Thanks @myd7349 (#961, f4c737e)
• Fix spdlog not printing message if SPDLOG_NO_THREAD_ID is defined. Thanks @scribam (#970, f4c737e)
• Fix depending on the order of inclusion of spdlog.h. Thanks @gocarlos (#959, 23fdc0e)

Version 1.3.0

Improvements

• Upgraded to the latest and greatest fmt library version 5.3.0.

• New API for default logger spdlog::trace(..), spdlog::debug(..), spdlog::info(..), etc.
  For convenience, spdlog now creates a default global logger (to stdout, colored and multithreaded).
  It can be used easily by calling spdlog::info(..), spdlog::debug(..), etc directly without any preparations.

  It's instance can be replaced to any other logger (shared_ptr):

  spdlog::set_default_logger(some_other_logger);
  spdlog::info("Use the new default logger");

• Alignment support in log patterns.
  Each pattern flag can be aligned by prepending a width number(upto 128).
  Use-(left align) or = (center align) to control the align side:

  align	meaning	example	result
  %<width><flag>	Align to the right	%8l	"    info"
  %-<width><flag>	Align to the left	%-8l	"info    "
  %=<width><flag>	Align to the center	%=8l	"  info  "

• Support for logging source filename, line number, and function name (thanks @possiblyhuman for contributing to this effort)

  flag	meaning	example
  %@	Source file and line (use SPDLOG_TRACE(..),SPDLOG_INFO(...) etc.)	my_file.cpp:123
  %s	Source file (use SPDLOG_TRACE(..),SPDLOG_INFO(...) etc.)	my_file.cpp
  %#	Source line (use SPDLOG_TRACE(..),SPDLOG_INFO(...) etc.)	123
  %!	Source function (use SPDLOG_TRACE(..),SPDLOG_INFO(...) etc. see tweakme for pretty-print)	my_func

• Support for compile time check of log levels using #define SPDLOG_ACTIVE_LEVEL <level>.
  Use LOG_TRACE(..), LOG_DEBUG(..), LOG_INFO(..), etc. to enable.
  Those macros check at compile time the log level and translate to empty statement if the log level is not high enough. Even if a log macro evaluate to a log call, the macro will check at runtime the level before evaluating its arguments.
  So for example the following won't evaluate some_costly_function() because the logger's level is error:

  #define SPDLOG_ACTIVE_LEVEL SPDLOG_LEVEL_DEBUG
  #include "spdlog/spdlog.h"
   ..
   spdlog::set_level(error);
   SPDLOG_DEBUG("Some costly arg: {}", some_costly_function());

• CMake improvements. Thanks @dpacbach (85b4d7c, f5dc166 ).

• Numerous small performance optimizations.

• Global option that disables global registration of loggers set_automatic_registration(bool). Thanks @pabloariasal (#892).

• Optimize logging of C strings by using string_view to avoid unnecessary copy. Thanks @peergynt (cb71fea).

• Use google benchmark to test latencies.

Fixes

• logger::error_handler() should be const (#881, thanks @shoreadmin for reporting)
• Cleanup header file: remove log_msg.h include from fmt_helper.h. Thanks @peergynt (1b391cc)
• Fix log_msg constructor doesn't initialize all fields (#888. Thanks @curiouserrandy for reporting).
• Change log_msg&& to log_msg& params. Thanks @rwen2012 (794a636)
• Fix typo in Android example. Thanks @zamazan4ik (f5a2725)
• Fix Compiling error VS2017 #902 (Thanks @JaNurz for reprting).
• Fix thread id is prefixed with zeros #908 (Thanks @klrakiranpradeep for reporting).
• Fix OSX build. Thanks @DanielChabrowski (c7f42d1).
• Fix and optimize usage of fmt::internal::count_digits(..) for better support 32/64 bits. Thanks @DanielChabrowski (c7f42d1, f1ab6fe).
• Better handling of rotation errors (b64e446).
• Fix exceptions on file size calculation on Windows XP x64 and Windows Server 2003 x64. Thanks @lestera (#926).
• Do not attempt to default operator= when it is implicitly deleted. Thanks @dpacbach (63a475d).
• Make an implicit cast from int --> uint32_t explicit. Thanks @dpacbach (a6152eb).
• Enable testing in the Travis config file. Thanks @dpacbach (f5dc166).
• Fix the text alignment in the example. Thanks @bzindovic (d6086da4856df510657ffe4ef6b894e902b4b83).
• Fix typos. Thanks @peergynt (ce8cf1e).
• Fix handling of external fmt lib in cmake. Thanks @cneumann (084bc72).
• Fix VC WinRT compilation. Thanks @taniey for reporting (@948).
• Fix typo in file_helper.h. Thanks @brridder (fb702f9).

Version 1.2.1

This fixes a compilation error of dist_sink.h (#864) . Thanks @DimRochette !

Version 1.2.0

Improvements

• Upgraded to latest fmt version 5.2.1.
• Binary data logging using spdlog::to_hex(binary_data). Many types of std::container<char> can be logged in hex. See usage examples.
• Added logger->clone() to ease the creation of new loggers from an existing one.
• Numerous micro optimizations across the lib.
• Added set_sinks method to dist_sink for atomic updating set of sinks in dist_sink. Thanks @jwnimmer-tri .
• Improved CmakeLists.txt to better handle third-party usage. Thanks @taketwo .

Fixes

• Fixed wchar logging (supported only in windows. #851 , #764).
• Fixed registry test. Thanks @DanielChabrowski .
• Removed invalid files from tests.sln. Thanks @yhchen .
• Some fixes to console_globals.h includes. Thanks @DanielChabrowski
• Don't deny access to log files from other processes under windows. Thanks @eruiz.
• Pessimizing move remove. Thanks @maciekgajewski
• ansicolor_sink.h - add missing sink include. Thanks @AlexanderDalshov .
• Improved rotating sink error handling.
• Fixed Readme. Thanks @blackball .
• Fixed some clang tidy warnings.

Version 1.1.0

Bug fixes

• Fixed android sink compilation. Thanks @rajesh-p .
• Fixed race condition in async-factory.
• Fixed bug in spdlog_ex implementation .Thanks @gajanak for reporting.
• Fixed race condition in the unit tests.
• Fixed compiler warnings under OSX. Thanks @baishuai .

Improvements

• Some micro optimizations.
• Improve and fix CMake issues. Thanks @DanielChabrowski .
• Improve and fix travis-ci issues. Thanks @DanielChabrowski .
• Added overrun_counter() to the async thread pool queue - returns # of messages overrun under the overrun_oldest mode. Thanks @indiosmo .
• Fixed some clang tidy warnings.