spdlog/README.md

140 lines
5.0 KiB
Markdown
Raw Normal View History

2014-10-31 21:20:54 -04:00
# spdlog
2014-10-31 21:40:52 -04:00
Very fast, header only, C++ logging library.
2014-10-31 21:20:54 -04:00
## 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
2014-11-05 15:54:13 -05:00
* mingw with g++ 4.9.x
2014-10-31 21:20:54 -04:00
##Features
2015-01-07 19:06:53 -05:00
* Very fast - performance is the primary goal (see [benchmarks](#benchmarks) below).
2014-11-22 03:27:01 -05:00
* Headers only.
2014-12-07 13:27:21 -05:00
* No dependencies - just copy and use.
2014-11-22 03:27:01 -05:00
* Cross platform - Linux / Windows on 32/64 bits.
2014-12-07 13:26:42 -05:00
* **new!** Feature rich [call style](#usage-example) using the excellent [cppformat](http://cppformat.github.io/) library.
2014-12-08 18:36:41 -05:00
* ostream call style is supported too.
2014-12-20 19:54:49 -05:00
* Extremely fast asynchronous mode (optional) - using lockfree queues and other tricks to reach millions of calls/sec.
2014-11-22 03:27:01 -05:00
* [Custom](https://github.com/gabime/spdlog/wiki/Custom-formatting) 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](include/spdlog/sinks/sink.h) interface).
2014-12-20 20:14:35 -05:00
* Severity based filtering - threshold levels can be modified in runtime as well as in compile time.
2014-11-22 03:27:01 -05:00
2014-11-03 19:47:26 -05:00
## Benchmarks
2014-11-03 18:43:20 -05:00
2014-12-20 15:32:03 -05:00
Below are some [benchmarks](bench) comparing popular log libraries under Ubuntu 64 bit, Intel i7-4770 CPU @ 3.40GHz
2014-11-03 18:52:30 -05:00
2014-12-20 15:33:17 -05:00
#### Synchronous mode
2014-12-20 19:50:36 -05:00
Time needed to log 1,000,000 lines in synchronous mode (in seconds, the best of 3 runs):
2014-12-20 15:32:50 -05:00
|threads|boost log|glog |easylogging |spdlog|
|-------|:-------:|:-----:|----------:|------:|
2014-12-20 15:35:10 -05:00
|1| 4.169s |1.066s |0.975s |0.302s|
2014-12-20 15:35:58 -05:00
|10| 16.029 |3.032s |2.857s |0.968s|
2014-12-20 15:35:10 -05:00
|100| 15.008 |1.139s |4.512s |0.497s|
2014-12-20 15:33:17 -05:00
#### Asynchronous mode
2014-12-20 19:50:36 -05:00
Time needed to log 1,000,000 lines in asynchronous mode, i.e. the time it takes to put them in the async queue (in seconds, the best of 3 runs):
2014-12-20 15:29:52 -05:00
2014-12-20 19:38:32 -05:00
|threads|g2log <sup>async logger</sup> |spdlog <sup>async mode</sup>|
2014-12-20 15:27:13 -05:00
|:-------|:-----:|-------------------------:|
|1| 1.850s |0.216s |
|10| 0.943s |0.173s|
2014-12-20 15:35:58 -05:00
|100| 0.959s |0.202s|
2014-11-22 19:05:17 -05:00
2014-11-03 18:43:20 -05:00
2014-10-31 21:20:54 -04:00
## Usage Example
2014-11-03 07:40:12 -05:00
```c++
2014-10-31 21:20:54 -04:00
#include <iostream>
#include "spdlog/spdlog.h"
int main(int, char* [])
{
namespace spd = spdlog;
try
{
2014-12-06 23:01:10 -05:00
//Create console, multithreaded logger
2014-11-03 02:00:28 -05:00
auto console = spd::stdout_logger_mt("console");
2014-10-31 21:20:54 -04:00
console->info("Welcome to spdlog!") ;
2014-12-06 23:01:10 -05:00
console->info("An info message example {}..", 1);
console->info() << "Streams are supported too " << 1;
2014-12-22 07:02:21 -05:00
2014-12-22 07:04:38 -05:00
//Formatting examples
2014-12-06 22:05:01 -05:00
console->info("Easy padding in numbers like {:08d}", 12);
2014-12-06 22:33:33 -05:00
console->info("Support for int: {0:d}; hex: {0:x}; oct: {0:o}; bin: {0:b}", 42);
2014-12-06 23:01:10 -05:00
console->info("Support for floats {:03.2f}", 1.23456);
console->info("Positional args are {1} {0}..", "too", "supported");
2014-12-06 22:05:01 -05:00
console->info("{:<30}", "left aligned");
console->info("{:>30}", "right aligned");
console->info("{:^30}", "centered");
2014-12-22 07:04:01 -05:00
//
// Runtime log levels
2014-12-22 07:03:32 -05:00
//
2014-12-22 07:02:21 -05:00
spd::set_level(spd::level::info); //Set global log level to info
console->debug("This message shold not be displayed!");
console->set_level(spd::level::info); // Set specific logger's log level
console->info("Now it should..");
2014-12-22 07:03:32 -05:00
//
2014-12-20 19:35:41 -05:00
// Create a file rotating logger with 5mb size max and 3 rotated files
2014-12-22 07:02:21 -05:00
//
2014-12-08 04:38:33 -05:00
auto file_logger = spd::rotating_logger_mt("file_logger", "logs/mylogfile", 1048576 * 5, 3);
2014-12-07 00:16:45 -05:00
for(int i = 0; i < 10; ++i)
file_logger->info("{} * {} equals {:>10}", i, i, i*i);
2014-12-06 23:01:10 -05:00
2014-12-22 07:03:32 -05:00
//
2014-12-20 19:35:41 -05:00
// Customize msg format for all messages
2014-12-22 07:02:21 -05:00
//
2014-12-06 23:01:10 -05:00
spd::set_pattern("*** [%H:%M:%S %z] [thread %t] %v ***");
file_logger->info("This is another message with custom format");
spd::get("console")->info("loggers can be retrieved from a global registry using the spdlog::get(logger_name) function");
2014-12-22 07:03:32 -05:00
//
// Compile time debug or trace macros.
// Enabled #ifdef SPDLOG_DEBUG_ON or #ifdef SPDLOG_TRACE_ON
//
2014-12-18 03:12:06 -05:00
SPDLOG_TRACE(console, "Enabled only #ifdef SPDLOG_TRACE_ON..{} ,{}", 1, 3.23);
SPDLOG_DEBUG(console, "Enabled only #ifdef SPDLOG_DEBUG_ON.. {} ,{}", 1, 3.23);
2014-12-20 20:12:35 -05:00
2014-12-22 07:02:21 -05:00
//
2014-12-08 04:38:33 -05:00
// Asynchronous logging is very fast..
// Just call spdlog::set_async_mode(q_size) and all created loggers from now on will be asynchronous..
2014-12-22 07:02:21 -05:00
//
2014-12-06 23:45:37 -05:00
size_t q_size = 1048576; //queue size must be power of 2
spdlog::set_async_mode(q_size);
2014-12-06 23:01:10 -05:00
auto async_file= spd::daily_logger_st("async_file_logger", "logs/async_log.txt");
async_file->info() << "This is async log.." << "Should be very fast!";
2014-12-22 07:02:21 -05:00
//
2014-12-20 19:34:52 -05:00
// syslog example. linux only..
2014-12-22 07:02:21 -05:00
//
2014-12-20 19:32:23 -05:00
#ifdef __linux__
2014-12-20 19:30:33 -05:00
std::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. This is Linux only!");
2014-12-20 19:32:23 -05:00
#endif
2014-10-31 21:20:54 -04:00
}
catch (const spd::spdlog_ex& ex)
{
std::cout << "Log failed: " << ex.what() << std::endl;
}
}
```