Zlog日志

注释控制日志打印

//printf("app start\n");
printf("app start\n");
printf("app start\n");
//printf("app start\n");
printf("app start\n");
//printf("app start\n");
printf("app start\n");

特点: 麻烦,产品发布时要注释所有日志, 开发时要打开日志

define 控制日志打印

#include <stdio.h>
// #define OPEN_LOG 1
int main(int argc, char const *argv[])
{
#ifdef OPEN_LOG
    printf("app start\n");
#endif
    printf("constant.\n");
#ifdef OPEN_LOG
    printf("app start\n");
#endif
    return 0;
}

特点: 比注释高效, 但每次打印日志都需要加#ifdef OPEN_LOG和#endif

日志打印工具文件

log.c

#include "log.h"
char *EM_LOGLevelGet(const int level)
{
    switch (level)
    {
    case LOG_DEBUG:
        return "DEBUG";
    case LOG_INFO:
        return "INFO";
    case LOG_WARN:
        return "WARN";
    case LOG_ERROR:
        return "ERROR";
    default:
        return "UNKNOW";
    }
}
void EM_LOG(const int level, const char *fun, const int line, const char *fmt, ...)
{
#ifdef OPEN_LOG
    va_list arg;
    va_start(arg, fmt);
    char buf[vsnprintf(NULL, 0, fmt, arg)];
    vsnprintf(buf, sizeof(buf) + 1, fmt, arg);
    va_end(arg);
    if (level >= LOG_LEVEL)
    {
        printf("[%s] [%s %d] %s\n", EM_LOGLevelGet(level), fun, line, buf);
    }
#endif
}

log.h

#ifndef __EM_LOG_H__
#define __EM_LOG_H__

#include<stdio.h>
#include <stdarg.h>
#define OPEN_LOG 1
#define LOG_LEVEL LOG_DEBUG

typedef enum
{
    LOG_DEBUG = 0,
    LOG_INFO,
    LOG_WARN,
    LOG_ERROR,
} E_LOGLEVEL;

extern void EM_LOG(const int level, const char *fun, const int line, const char *fmt, ...);

#define EMLog(level, fmt...) EM_LOG(level, __FUNCTION__, __LINE__, fmt)

#endif

调用日志文件

#include<stdio.h>
#include"log.h"
int main(int argc, char const *argv[])
{
    int a = 10, b = 11;
    // EM_LOG(LOG_DEBUG, "app LOG_DEBUG");
    // EM_LOG(LOG_INFO, "A = %d", a);
    // EM_LOG(LOG_WARN, "app LOG_WARN");
    // EM_LOG(LOG_ERROR, "app LOG_ERROR");
    EMLog(LOG_DEBUG, "app_start");
    return 0;
}