51工具盒子

依楼听风雨
笑看云卷云舒,淡观潮起潮落

C++日志库spdlog

使用方法 {#使用方法}

spdlog是基于C++ 11的日志组件,它非常轻量,使用时你仅仅需要引入头文件就可以了。

spdlog下载链接
或使用命令下载

|-----------|-----------------------------------------------| | 1 | wget https://github.com/gabime/spdlog |

下载完成后,将includ/spdlog目录单独拷贝到自己的工程目录,g++编译文件头路径添加include/spdlog即可,spdlog一级目录为:

|---------------------------------------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------| | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 | -bash-4.2$ ll ../spdlog/ total 56 -rw-rw-r--. 1 centos centos 988 Dec 30 07:43 appveyor.yml drwxrwxr-x. 2 centos centos 148 Dec 30 07:43 bench drwxrwxr-x. 2 centos centos 116 Dec 30 07:43 cmake -rw-rw-r--. 1 centos centos 11996 Dec 30 07:43 CMakeLists.txt drwxrwxr-x. 2 centos centos 66 Dec 30 07:43 example drwxrwxr-x. 3 centos centos 20 Dec 30 07:43 include -rw-rw-r--. 1 centos centos 661 Dec 30 07:43 INSTALL -rw-rw-r--. 1 centos centos 1142 Dec 30 07:43 LICENSE -rw-rw-r--. 1 centos centos 4682 Dec 30 07:43 meson.build -rw-rw-r--. 1 centos centos 1773 Dec 30 07:43 meson_options.txt -rw-rw-r--. 1 centos centos 12669 Dec 30 07:43 README.md drwxrwxr-x. 2 centos centos 110 Dec 30 07:43 scripts drwxrwxr-x. 2 centos centos 125 Dec 30 07:43 src drwxrwxr-x. 2 centos centos 4096 Dec 30 07:43 tests -bash-4.2$ |

修改CMakeLists.txt文件,增加头文件搜索路径

|---------------------|----------------------------------------------------------------------------------------------------------------------------------------------| | 1 2 3 4 5 6 | INCLUDE_DIRECTORIES( /usr/include/ ${PROJECT_SOURCE_DIR}/src/ ${PROJECT_SOURCE_DIR}/include/ ${PROJECT_SOURCE_DIR}/include/spdlog/ ) |

线程安全 {#线程安全}

命名空间 spdlog:: 下面的大多数方法是线程安全的。已知以下三个是线程不安全的,使用时请注意:

|---------------|---------------------------------------------------------------------------------------------------------------------------------------------------| | 1 2 3 | void spdlog::set_pattern(const std::string&); void spdlog::set_formatter(formatter_ptr); void spdlog::set_error_handler(log_err_handler); |

日志对象的大部分方法也是线程安全的,除了:

|---------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------| | 1 2 3 | void spdlog::logger::set_pattern(const std::string&); void spdlog::logger::set_formatter(formatter_ptr); void spdlog::set_error_handler(log_err_handler); |

_mt的意思是multi thread(速度稍微慢一点点,考虑了多线程并发),_st的意思是single thread(速度较块)。所有以_mt结尾的SINK都是线程安全的,以_st结尾的则不是。

使用规则示例 {#使用规则示例}

|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------| | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 | #include "spdlog/spdlog.h" #include <iostream> // 多线程的基于控制台(stdout)的日志记录器,支持高亮。类似的stdout_color_st是单线程版本 auto console = spdlog::stdout_color_mt( "console" ); // 基于文件的简单日志 auto logger = spdlog::basic_logger_mt("basic_logger", "logs/basic.txt"); // 基于滚动文件的日志,每个文件5MB,三个文件 auto logger = spdlog::rotating_logger_mt("file_logger", "myfilename", 1024 * 1024 * 5, 3); // 定制输出格式 spdlog::set_pattern("*** [%H:%M:%S %z] [thread %t] %v ***"); // 多个日志器共享SINK auto daily_sink = std::make_shared<spdlog::sinks::daily_file_sink_mt>("logfile", 23, 59); // 下面几个同步日志器共享的输出到目标文件 auto net_logger = std::make_shared<spdlog::logger>("net", daily_sink); auto hw_logger = std::make_shared<spdlog::logger>("hw", daily_sink); auto db_logger = std::make_shared<spdlog::logger>("db", daily_sink); // 一个日志器使用多个SINK std::vector<spdlog::sink_ptr> sinks; sinks.push_back( std::make_shared<spdlog::sinks::stdout_sink_st>()); sinks.push_back( std::make_shared<spdlog::sinks::daily_file_sink_st>( "logfile", 23, 59 )); auto combined_logger = std::make_shared<spdlog::logger>( "name", begin( sinks ), end( sinks )); spdlog::register_logger( combined_logger ); // 异步 // 每个日志器分配8192长度的队列,队列长度必须2的幂 spdlog::set_async_mode(8192); // 程序退出前清理 spdlog::drop_all(); // 注册日志器 spdlog::register_logger(net_logger); // 注册后,其它代码可以根据名称获得日志器 auto logger = spdlog::get(net_logger); // 记录日志 // 设置最低级别 console->set_level(spdlog::level::debug); console->debug("Hello World") ; // 使用占位符 console->info("Hello {}" ,"World"); // 带格式化的占位符:d整数,x十六进制,o八进制,b二进制 console->warn("Support for int: {0:d}; hex: {0:x}; oct: {0:o}; bin: {0:b}", 42); // 带格式化的占位符:f浮点数 console->info("Support for floats {:03.2f}", 1.23456); // 左对齐,保证30字符宽度 console->error("{:<30}", "left aligned"); // 指定占位符位置序号 console->info("Positional args are {1} {0}..", "too", "supported"); // 记录自定义类型,需要重载<<操作符 #include <spdlog/fmt/ostr.h> class Duck{} std::ostream& operator<<(std::ostream& os, const Duck& duck){ return os << duck.getName(); } Duck duck; console->info("custom class with operator<<: {}..", duck); |

输出格式 {#输出格式}

spdlog默认的输出格式为:

|-----------|-----------------------------------------------------------------------| | 1 | [2014-31-10 23:46:59.678] [info] [my_loggername] Some message |

要定制输出格式,可以调用:

|---------------|-----------------------------------------------------------------------------------------------------------------| | 1 2 3 | spdlog::set_pattern(pattern_string); // 示例 spdlog::set_pattern("*** [%H:%M:%S %z] [thread %t] %v ***"); |

或者实现自己的格式化器:

|-----------|-------------------------------------------------------------------------| | 1 | spdlog::set_formatter(std::make_shared<my_custom_formatter>()); |

Pattern说明 {#Pattern说明}

输出格式的Pattern中可以有若干 %开头的标记,含义如下表:

| flag | meaning | example | |-------|-----------------------------------------------------------------------|------------------------------------------------------------------| | %v | 实际需要被日志记录的文本,如果文本中有{占位符}会被替换 | "my log test content" | | %t | 线程标识符 | "123" | | %P | 进程标识符 | "234" | | %n | 日志记录器名称 | "basicLogger" | | %l | 日志级别 | "debug", "info", etc | | %L | 日志级别简称 | "D", "I", etc | | %a | 星期几(简称) | "Thu" | | %A | 星期几 | "Thursday" | | %b | 月份简称 | "Aug" | | %B | 月份 | "August" | | %c | 日期时间 | "Thu Aug 23 15:35:46 2014" | | %C | 年(两位) | "14" | | %Y | 年 | "2014" | | %D %x | 日期简写 | "08/23/14" | | %m | 月份(数字) | "11" | | %d | 日(数组) | "29" | | %H | 小时(24制) | "23" | | %I | 小时(12制) | "11" | | %M | 分钟 | "59" | | %S | 秒 | "58" | | %e | 毫秒 | "678" | | %f | 微秒 | "056789" | | %F | 纳秒 | "256789123" | | %p | AM/PM | "AM" | | %r | 时间(12制) | "02:55:02 pm" | | %R | 时分(24制) | "23:55" | | %T %X | 时间(24制) | "23:55:59" | | %z | 时区(偏移) | "+02:00" | | %E | epoch(秒) | "1528834770" | | %% | 百分号 | "%" | | %+ | 默认格式 | "[2014-10-31 23:46:59.678] [mylogger] [info] Some message" | | %^ | start color range (can be used only once) | "[mylogger] [info(green)] Some message" | | %$ | end color range (for example %^[+++]%$ %v) (can be used only once) | [+++] Some message | | %@ | 文件名与行数 | my_file.cpp:123 | | %s | 文件名 | my_file.cpp | | %g | 文件名(含路径) | /some/dir/my_file.cpp | | %# | 行数 | 123 | | %! | 函数名 | my_func | | %o | 相对上一条记录的时间间隔(毫秒) | 456 | | %i | 相对上一条记录的时间间隔(微秒) | 456 | | %u | 相对上一条记录的时间间隔(纳秒) | 11456 | | %O | 相对上一条记录的时间间隔(秒) | 4 |

spdlog示例 {#spdlog示例}

|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------| | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 | #include "spdlog/spdlog.h" #include "spdlog/sinks/daily_file_sink.h" #include <memory> #include "spdlog/spdlog.h" #include "spdlog/sinks/basic_file_sink.h" namespace spd = spdlog; using namespace std; int main(int argc, char **argv) { //创建文件名类似于: daily_log_2018-01-17_10-27.txt,如果程序不退出的话,就是每天2:30 am创建新的文件 { auto console= spd::daily_logger_mt("maitianPT", "./daily_log.txt", 2, 30); //写入文档 console->info("test daily info 提示信息"); console->warn("test daily warn 警告"); console->error("test daily error 错误"); console->critical("test daily critical 致命"); } // 打印到控制台的信息,不同日志级别,颜色不同 { spdlog::info("Welcome to spdlog!"); spdlog::error("Some error message with arg: {}", 1); spdlog::warn("Easy padding in numbers like {:08d}", 12); spdlog::critical("Support for int: {0:d}; hex: {0:x}; oct: {0:o}; bin: {0:b}", 42); spdlog::info("Support for floats {:03.2f}", 1.23456); spdlog::info("Positional args are {1} {0}..", "too", "supported"); spdlog::info("{:<30}", "left aligned"); spdlog::set_level(spdlog::level::debug); // Set global log level to debug spdlog::debug("This message should be displayed.."); // change log pattern spdlog::set_pattern("[%H:%M:%S %z] [%n] [%^---%L---%$] [thread %t] %v"); // Compile time log levels // define SPDLOG_ACTIVE_LEVEL to desired level SPDLOG_TRACE("Some trace message with param {}", 42); SPDLOG_DEBUG("Some debug message"); } // Set the default logger to file logger,创建普通日志文件 auto file_logger = spdlog::basic_logger_mt("basic_logger", "logs/basic.txt"); spdlog::set_default_logger(file_logger); for (int i = 0; i < 1000; i ++) { file_logger->info("Test File Logger {}", i); } return 0; } |


赞(1)
未经允许不得转载:工具盒子 » C++日志库spdlog