LoggerXX

Github project page

A modern C++ logger based on Boost::Format

Copyright © Gordon "Lee" Morgan May 2016. This project is released under the MIT License

Why another logging library

• Portability

  Traditional logging libraries which use printf style formatting strings work well when you use legacy C data types; int, float, char, pointers, etc. This breaks down for types such as uint64_t and long long. Other types such as size_t and off_t can change size between 32 and 64 bit compiles on the same platform. Logging macros should not need conditional compilation to compile cleanly between multiple platforms or targets.

• Type safety

  C++ types such as std::string and std::chrono::time_point cannot be used with printf without conversion. User defined types almost never are useable as printf without helper functions. LoggerXX can be used with any type that provides a ostream >> operator or provides a helper function.

• Dependencies

  LoggerXX only requires two libraries to use, Boost and Date. Date is a "header only" library and is an external submodule. Boost is a very common dependency and is effectively free for a large number of projects.

• Streaming and Format string APIs

  LoggerXX allows the mixing of both format string and streaming log apis simplifying code migration or mixing source code from multiple sources.

• Functionality

  LoggerXX is designed to easily replace simple printf derived loggers and offer advanced functionality with low overhead

• Performance

  LoggerXX is intended to be enabled in both debug and release builds with a minimal performance hit. This has a number desirable effects:

  1. This will eliminate a number of "unused variable" warnings that typically occur in release builds when return values are logged.
  2. Functions can safely be used in logging macros, classic "nop" macros will remove these calls in release builds.
  3. You can enable a ring buffer that collects all log messages to write into a crash log, regardless of log level.

Design goals

1. A drop in replacement for "C printf" style logging
2. C++ type safe
3. extensible types
4. By module, file, class, function or line log configuration
5. high performance Always On logging
6. Ring buffer critical error log
7. Multiple log output sinks