spdlog是一個(gè)開(kāi)源的、快速的、僅有頭文件的C++11 日志庫(kù)，code地址在 https://github.com/gabime/spdlog?，目前最新的發(fā)布版本為0.14.0。它提供了向流、標(biāo)準(zhǔn)輸出、文件、系統(tǒng)日志、調(diào)試器等目標(biāo)輸出日志的能力。它支持的平臺(tái)包括Windows、Linux、Mac、Android。

spdlog特性：

(1)、非?？?#xff0c;性能是它的主要目標(biāo)；

(2)、僅包括頭文件；

(3)、日志的格式化處理使用開(kāi)源的fmt庫(kù)( ?https://github.com/fmtlib/fmt )；

(4)、可選的printf語(yǔ)法支持；

(5)、非常快的異步模式(可選)，支持異步寫(xiě)日志；

(6)、自定義格式；

(7)、條件日志；

(8)、多線程/單線程日志；

(9)、各種日志目標(biāo)：可對(duì)日志文件進(jìn)行循環(huán)輸出；可每日生成日志文件；支持控制臺(tái)日志輸出(支持顏色)；系統(tǒng)日志；Windows debugger；較容易擴(kuò)展自定義日志目標(biāo)；

(10)、支持日志輸出級(jí)別：閾值級(jí)別既可以在運(yùn)行時(shí)也可以在編譯時(shí)修改。

以下是測(cè)試代碼，主要來(lái)自spdlog/example/example.cpp:

#include "funset.hpp"
#include <iostream>
#include "spdlog/spdlog.h"
#include "spdlog/fmt/ostr.h"namespace spd = spdlog;int test_spdlog_console()
{try {// Console logger with colorauto console = spd::stdout_color_mt("console");console->info("Welcome to spdlog!");console->error("Some error message with arg{}..", 1);// Conditional logging exampleconsole->info_if(true, "Welcome to spdlog conditional logging!");// Formatting examplesconsole->warn("Easy padding in numbers like {:08d}", 12);console->critical("Support for int: {0:d};  hex: {0:x};  oct: {0:o}; bin: {0:b}", 42);console->info("Support for floats {:03.2f}", 1.23456);console->info("Positional args are {1} {0}..", "too", "supported");console->info("{:<30}", "left aligned");SPDLOG_DEBUG_IF(console, true, "This is a debug log");spd::get("console")->info("loggers can be retrieved from a global registry using the spdlog::get(logger_name) function");// Create basic file logger (not rotated)auto my_logger = spd::basic_logger_mt("basic_logger", "E:/GitCode/Messy_Test/testdata/basic_log");my_logger->info("Some log message");// Create a file rotating logger with 5mb size max and 3 rotated filesauto rotating_logger = spd::rotating_logger_mt("some_logger_name", "E:/GitCode/Messy_Test/testdata/mylogfile_log", 1048576 * 5, 3);for (int i = 0; i < 10; ++i)rotating_logger->info("{} * {} equals {:>10}", i, i, i*i);// Create a daily logger - a new file is created every day on 2:30amauto daily_logger = spd::daily_logger_mt("daily_logger", "E:/GitCode/Messy_Test/testdata/daily_log", 2, 30);// trigger flush if the log severity is error or higherdaily_logger->flush_on(spd::level::err);daily_logger->info(123.44);// Customize msg format for all messagesspd::set_pattern("*** [%H:%M:%S %z] [thread %t] %v ***");rotating_logger->info("This is another message with custom format");// Runtime log levelsspd::set_level(spd::level::info); //Set global log level to infoconsole->debug("This message shold not be displayed!");console->set_level(spd::level::debug); // Set specific logger's log levelconsole->debug("This message shold be displayed..");// Compile time log levels// define SPDLOG_DEBUG_ON or SPDLOG_TRACE_ONSPDLOG_TRACE(console, "Enabled only #ifdef SPDLOG_TRACE_ON..{} ,{}", 1, 3.23);SPDLOG_DEBUG(console, "Enabled only #ifdef SPDLOG_DEBUG_ON.. {} ,{}", 1, 3.23);SPDLOG_DEBUG_IF(console, true, "This is a debug log");// Apply a function on all registered loggersspd::apply_all([&](std::shared_ptr<spdlog::logger> l) { l->info("End of example."); });// Release and close all loggersspdlog::drop_all();}// Exceptions will only be thrown upon failed logger or sink construction (not during logging)catch (const spd::spdlog_ex& ex) {std::cout << "Log init failed: " << ex.what() << std::endl;return -1;}return 0;
}int test_spdlog_async()
{// Asynchronous logging is very fast..// Just call spdlog::set_async_mode(q_size) and all created loggers from now on will be asynchronous..size_t q_size = 4096; //queue size must be power of 2spdlog::set_async_mode(q_size);auto async_file = spd::daily_logger_st("async_file_logger", "E:/GitCode/Messy_Test/testdata/async_log");for (int i = 0; i < 100; ++i)async_file->info("Async message #{}", i);return 0;
}int test_spdlog_syslog()
{// there is no syslog.h file in windows, so macro SPDLOG_ENABLE_SYSLOG should be disenable
#ifdef SPDLOG_ENABLE_SYSLOGstd::string ident = "spdlog-example";auto syslog_logger = spd::syslog_logger("syslog", ident, LOG_PID);syslog_logger->warn("This is warning that will end up in syslog.");
#endifreturn 0;
}// user defined types logging by implementing operator<<
struct my_type {int i;template<typename OStream>friend OStream& operator<<(OStream& os, const my_type& c){return os << "[my_type i=" << c.i << "]";}
};int test_spdlog_user_defined()
{try {//spd::get("console")->info("user defined type: {}", my_type{ 14 });auto console = spd::stdout_color_mt("console");console->info("user defined type: {}", my_type{ 14 });} catch (const spd::spdlog_ex& ex) {std::cout << "user defined log fail: " << ex.what() << std::endl;return -1;}return 0;
}int test_spdlog_err_handler()
{// can be set globaly or per logger(logger->set_error_handler(..))spdlog::set_error_handler([](const std::string& msg){std::cerr << "my err handler: " << msg << std::endl;});//spd::get("console")->info("some invalid message to trigger an error {}{}{}{}", 3);auto console = spd::stdout_color_mt("console");console->info("some invalid message to trigger an error {}{}{}{}", 3);return 0;
}

執(zhí)行結(jié)果如下：

GitHub：?https://github.com/fengbingchun/Messy_Test

總結(jié)

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