C/C++格式化日志库实现代码

/*****************************************************//* 跨平台日志函数,Linux下与windows下亲测有效      *//*****************************************************/  #ifndef _LOG_FORMAT_H_#define _LOG_FORMAT_H_ // 日志等级enum LogLevel { _LOG_TRACE, _LOG_INFO, _LOG_WARN, _LOG_ERROR, _LOG_FATAL };void LogFormat(const char *pszFileName, const int nLine, LogLevel Level, const char *Format, ...); /******************************************************//* 日志函数调用方法  _LOG(_LOG_FATAL, "%s", "sss"); *//******************************************************/#ifndef _LOG#define _LOG(Level, Format, ...) LogFormat(__FILE__, __LINE__, Level, Format, ##__VA_ARGS__)#endif #endif // _LOG_FORMAT_H_

#include <string>#include <stdio.h>#include <stdarg.h>#include <stdint.h> #if defined __GNUC__ || defined LINUX#include <sys/time.h>#define MY_VA_LIST _G_va_list#else#include <windows.h>#define MY_VA_LIST va_list#endif #include "LogFormat.h" /* *最终生成的日志字符串最大长度,要特别注意*超过此长度程序会崩溃,用户可以自定义长度*/#define LOG_MAX 1024 /**时间长度,不需要修改*/#define FORMAT_TIME_SIZE 24 /**日志等级字符串,与头文件中定义的枚举必须一致*/static std::string g_LogLevel[] = { "TRACE","INFO","WARN","ERROR","FATAL" }; /**内存申请函数,用户可以自定义*/static char *NewBuf(const uint32_t unBufSize){	return new char[unBufSize];} /**内存释放函数,必须与NewBuf对应*/static void DeleteBuf(char ** pszBuf){	if (NULL != *pszBuf)	{		delete[] *pszBuf;		*pszBuf = NULL;	}	*pszBuf = NULL;} /**获取当前时间字符串函数*2018-08-08 08:08:08.888*/static char* GetTime(){	char *pszFormatTime = NewBuf(FORMAT_TIME_SIZE);#if defined __GNUC__ || defined LINUX	struct timeval tv;	struct timezone tz;	gettimeofday(&tv, &tz);	struct tm *current_time = localtime(&tv.tv_sec);	sprintf(pszFormatTime,		"%04d-%02d-%02d %02d:%02d:%02d.%03d",		current_time->tm_year + 1900,		current_time->tm_mon + 1,		current_time->tm_mday,		current_time->tm_hour,		current_time->tm_min,		current_time->tm_sec,		tv.tv_usec / 1000);#else	SYSTEMTIME sys_time;	GetLocalTime(&sys_time);#if _MSC_VER	sprintf_s(pszFormatTime,		FORMAT_TIME_SIZE,		"%04d-%02d-%02d %02d:%02d:%02d.%03d",		sys_time.wYear,		sys_time.wMonth,		sys_time.wDay,		sys_time.wHour,		sys_time.wMinute,		sys_time.wSecond,		sys_time.wMilliseconds);#else	sprintf(pszFormatTime,		"%04d-%02d-%02d %02d:%02d:%02d.%03d",		sys_time.wYear,		sys_time.wMonth,		sys_time.wDay,		sys_time.wHour,		sys_time.wMinute,		sys_time.wSecond,		sys_time.wMilliseconds);#endif#endif	return pszFormatTime;} void LogFormat(const char *pszFileName, const int nLine, LogLevel Level, const char *Format, ...){	int ret = 0;	char *pszDescribeInfo = NewBuf(LOG_MAX); 	MY_VA_LIST ap;	va_start(ap, Format);#if defined __GNUC__ || defined LINUX	ret = vsnprintf(pszDescribeInfo,		LOG_MAX,		Format,		ap);#else#if _MSC_VER	ret = _vsnprintf_s(pszDescribeInfo,		LOG_MAX,		_TRUNCATE,		Format,		ap);#else	ret = _vsnprintf(pszDescribeInfo,		LOG_MAX,		Format,		ap);#endif#endif	va_end(ap);	if ((LOG_MAX <= ret) || (0 > ret))	{		DeleteBuf(&pszDescribeInfo);		return;	} 	// 组装日志,[时间][等级][文件名(行数)][自定义字符串]	char *pszLog = NewBuf(LOG_MAX);	char *pszTime = GetTime();#if defined __GNUC__ || defined LINUX	ret = sprintf(pszLog,		"[%s][%s][%s(%d)][%s]",		pszTime,		g_LogLevel[Level].c_str(),		pszFileName,		nLine,		pszDescribeInfo);#else#if _MSC_VER	ret = sprintf_s(pszLog,		LOG_MAX,		"[%s][%s][%s(%d)][%s]",		pszTime,		g_LogLevel[Level].c_str(),		pszFileName,		nLine,		pszDescribeInfo);#else	ret = sprintf(pszLog,		"[%s][%s][%s(%d)][%s]",		pszTime,		g_LogLevel[Level].c_str(),		pszFileName,		nLine,		pszDescribeInfo);#endif#endif 	// 日志默认输出到控制台,用户可以自行修改	printf("%s/n", pszLog); 	DeleteBuf(&pszDescribeInfo);	DeleteBuf(&pszLog);	DeleteBuf(&pszTime);}