spdlog

Very fast, header only, C++ logging library.

Install

Just copy the files to your build tree and use a C++11 compiler

Tested on:

• gcc 4.8.1 and above
• clang 3.5
• visual studio 2013
• mingw with g++ 4.9.x

##Features

• Very fast - performance is the primary goal (see becnhmarks below).
• Headers only.
• No dependencies.
• Cross platform - Linux / Windows on 32/64 bits.
• Variadic-template/stream call styles: logger.info("variadic", x, y) << "or stream" << x << y;
• Custom formatting.
• Multi/Single threaded loggers.
• Various log targets:
  • Rotating log files.
  • Daily log files.
  • Console logging.
  • Linux syslog.
  • Easily extendable with custom log targets (just implement a single function in the sink interface).
• Optional async logging .
• Log levels.

Benchmarks

Below are some benchmarks under Ubuntu 64 bit, Intel i7-4770 CPU @ 3.40GHz:

Single thread bench

library	log lines	single thread	10 threads
boost log v1.56	1,000,000	4.207s	6.592s
glog v0.3.3	1,000,000	1.077s	1.678s
spdlog	1,000,000	0.975s	0.961s

10 threads bench

library	log lines	threads	elapsed
boost log v1.56	1,000,000	10	6.592s
glog v0.3.3	1,000,000	10	1.678s
spdlog	1,000,000	10	0.961s

Usage Example

#include <iostream>
#include "spdlog/spdlog.h"

int main(int, char* [])
{
    namespace spd = spdlog;

    try
    {
        std::string filename = "spdlog_example";
        auto console = spd::stdout_logger_mt("console");
        console->info("Welcome to spdlog!") ;
        console->info() << "Creating file " << filename << "..";

        auto file_logger = spd::rotating_logger_mt("file_logger", filename, 1024 * 1024 * 5, 3);
        file_logger->info("Log file message number", 1);

        for (int i = 0; i < 100; ++i)
        {
            auto square = i*i;
            file_logger->info() << i << '*' << i << '=' << square << " (" << "0x" << std::hex << square << ")";
        }

        // Change log level to all loggers to warning and above
        spd::set_level(spd::level::WARN);
        console->info("This should not be displayed");
        console->warn("This should!");
        spd::set_level(spd::level::INFO);

        // Change format pattern to all loggers
        spd::set_pattern(" **** %Y-%m-%d %H:%M:%S.%e %l **** %v");
        spd::get("console")->info("This is another message with different format");
    }
    catch (const spd::spdlog_ex& ex)
    {
        std::cout << "Log failed: " << ex.what() << std::endl;
    }
    return 0;
}