自定义log日志输出到文件中保存

程序调试日志，可以 通过printf直接输出到屏幕上面进行调试。在默写特定的情况下面，可以将日志保存到文件中，后期进行查阅调试。

log.h

//log.h
#ifndef _ITCAST_LOG_H_
#define _ITCAST_LOG_H_

/*
#define IC_NO_LOG_LEVEL			0
#define IC_DEBUG_LEVEL			1
#define IC_INFO_LEVEL			2
#define IC_WARNING_LEVEL		3
#define IC_ERROR_LEVEL			4;
*/

/************************************************************************/
/*
const char *file：文件名称
int line：文件行号
int level：错误级别
0 -- 没有日志
1 -- debug级别
2 -- info级别
3 -- warning级别
4 -- err级别
int status：错误码
const char *fmt：可变参数
*/
/************************************************************************/
//实际使用的Level
extern int  LogLevel[5];
void ITCAST_LOG(const char *file, int line, int level, int status, const char *fmt, ...);

#endif

log.c

//log.c
#define _CRT_SECURE_NO_WARNINGS
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <stdarg.h>
#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include "ItcastLog.h"

#define ITCAST_DEBUG_FILE_	"socketclient.log"
#define ITCAST_MAX_STRING_LEN 		10240

//Level类别
#define IC_NO_LOG_LEVEL			0
#define IC_DEBUG_LEVEL			1
#define IC_INFO_LEVEL			2
#define IC_WARNING_LEVEL		3
#define IC_ERROR_LEVEL			4

int  LogLevel[5] = { IC_NO_LOG_LEVEL, IC_DEBUG_LEVEL, IC_INFO_LEVEL, IC_WARNING_LEVEL, IC_ERROR_LEVEL };

//Level的名称
char ICLevelName[5][10] = { "NOLOG", "DEBUG", "INFO", "WARNING", "ERROR" };

static int ITCAST_Error_GetCurTime(char* strTime)
{
	struct tm*		tmTime = NULL;
	size_t			timeLen = 0;
	time_t			tTime = 0;

	tTime = time(NULL);
	tmTime = localtime(&tTime);
	//timeLen = strftime(strTime, 33, "%Y(Y)%m(M)%d(D)%H(H)%M(M)%S(S)", tmTime);
	timeLen = strftime(strTime, 33, "%Y.%m.%d %H:%M:%S", tmTime);

	return timeLen;
}

static int ITCAST_Error_OpenFile(int* pf)
{
	char	fileName[1024];

	memset(fileName, 0, sizeof(fileName));
#ifdef WIN32
	sprintf(fileName, "c:\\debuglog\\%s", ITCAST_DEBUG_FILE_);//log文件路径
#else
	sprintf(fileName, "%s/log/%s", getenv("HOME"), ITCAST_DEBUG_FILE_);
#endif

	*pf = open(fileName, O_WRONLY | O_CREAT | O_APPEND, 0666);
	if (*pf < 0)
	{
		return -1;
	}

	return 0;
}

static void ITCAST_Error_Core(const char *file, int line, int level, int status, const char *fmt, va_list args)
{
	char str[ITCAST_MAX_STRING_LEN];
	int	 strLen = 0;
	char tmpStr[64];
	int	 tmpStrLen = 0;
	int  pf = 0;

	//初始化
	memset(str, 0, ITCAST_MAX_STRING_LEN);
	memset(tmpStr, 0, 64);

	//加入LOG时间
	tmpStrLen = ITCAST_Error_GetCurTime(tmpStr);
	tmpStrLen = sprintf(str, "[%s] ", tmpStr);
	strLen = tmpStrLen;

	//加入LOG等级
	tmpStrLen = sprintf(str + strLen, "[%s] ", ICLevelName[level]);
	strLen += tmpStrLen;

	//加入LOG状态
	if (status != 0)
	{
		tmpStrLen = sprintf(str + strLen, "[ERRNO is %d] ", status);
	}
	else
	{
		tmpStrLen = sprintf(str + strLen, "[SUCCESS] ");
	}
	strLen += tmpStrLen;

	//加入LOG信息
	tmpStrLen = vsprintf(str + strLen, fmt, args);
	strLen += tmpStrLen;

	//加入LOG发生文件
	tmpStrLen = sprintf(str + strLen, " [%s]", file);
	strLen += tmpStrLen;

	//加入LOG发生行数
	tmpStrLen = sprintf(str + strLen, " [%d]\n", line);
	strLen += tmpStrLen;

	//打开LOG文件
	if (ITCAST_Error_OpenFile(&pf))
	{
		return;
	}

	//写入LOG文件
	write(pf, str, strLen);
	//IC_Log_Error_WriteFile(str);

	//关闭文件
	close(pf);

	return;
}

void ITCAST_LOG(const char *file, int line, int level, int status, const char *fmt, ...)
{
	va_list args;

	//判断是否需要写LOG
	//	if(level!=IC_DEBUG_LEVEL && level!=IC_INFO_LEVEL && level!=IC_WARNING_LEVEL && level!=IC_ERROR_LEVEL)
	if (level == IC_NO_LOG_LEVEL)
	{
		return;
	}

	//调用核心的写LOG函数
	va_start(args, fmt);
	ITCAST_Error_Core(file, line, level, status, fmt, args);
	va_end(args);

	return;
}

void main()
{
	int rv = -3;
	ITCAST_LOG(__FILE__, __LINE__, LogLevel[4], rv, "func cltSocketRev2: (buflen == NULL) [%d]", rv);
	system("pause");
}