/** log.h **/
 
#ifndef __LOG_H__
#define __LOG_H__
#include "stdio.h"
#include "string.h"
#include "stdlib.h"
#include "time.h"
#include "stdarg.h"
#include "unistd.h"
 
#define MAXLEN (2048)
#define MAXFILEPATH (512)
#define MAXFILENAME (50)
typedef enum{
	ERROR_1=-1,
	ERROR_2=-2,
	ERROR_3=-3
}ERROR0;
 
 
typedef enum{
	NONE=0,
	INFO=1,
	DEBUG=2,
	WARN=3,
	ERROR=4,
	ALL=255
}LOGLEVEL;
 
typedef struct log{
	char logtime[20];
	char filepath[MAXFILEPATH];
	FILE *logfile;
}LOG;
 
typedef struct logseting{
	char filepath[MAXFILEPATH];
	unsigned int maxfilelen;
	unsigned char loglevel;
}LOGSET;
 
int LogWrite(unsigned char loglevel,char *fromat,...);
#endif /* __LOG_H__ */
 

/** log.c **/
 
#include "log.h"
#define MAXLEVELNUM (3)
 
LOGSET logsetting;
LOG loging;
 
const static char LogLevelText[4][10]={"INFO","DEBUG","WARN","ERROR"};
 
static char * getdate(char *date);
 
static unsigned char getcode(char *path){
	unsigned char code=255;
	if(strcmp("INFO",path)==0)
		code=1;
	else if(strcmp("WARN",path)==0)
		code=3;
	else if(strcmp("ERROR",path)==0)
		code=4;
	else if(strcmp("NONE",path)==0)
		code=0;
	else if(strcmp("DEBUG",path)==0)
		code=2;
	return code;
}
 
static unsigned char ReadConfig(char *path){
	char value[512]={0x0};
	char data[50]={0x0};
 
	FILE *fpath=fopen(path,"r");
	if(fpath==NULL)
		return -1;
	fscanf(fpath,"path=%s\n",value);
	getdate(data);
	strcat(data,".log");
	strcat(value,"/");
	strcat(value,data);
	if(strcmp(value,logsetting.filepath)!=0)
		memcpy(logsetting.filepath,value,strlen(value));
	memset(value,0,sizeof(value));
 
	fscanf(fpath,"level=%s\n",value);
	logsetting.loglevel=getcode(value);
	fclose(fpath);
	return 0;
}
/*
 *日誌設定資訊
 * */
static LOGSET *getlogset(){
	char path[512]={0x0};
	getcwd(path,sizeof(path));
	strcat(path,"/log.conf");
	if(access(path,F_OK)==0){
		if(ReadConfig(path)!=0){
			logsetting.loglevel=INFO;
			logsetting.maxfilelen=4096;
		}
	}else{
		logsetting.loglevel=INFO;
		logsetting.maxfilelen=4096;
	}
	return &logsetting;
}
 
/*
 *獲取日期
 * */
static char * getdate(char *date){
	time_t timer=time(NULL);
	strftime(date,11,"%Y-%m-%d",localtime(&timer));
	return date;
}
 
/*
 *獲取時間
 * */
static void settime(){
	time_t timer=time(NULL);
	strftime(loging.logtime,20,"%Y-%m-%d %H:%M:%S",localtime(&timer));
}
 
/*
 *不定參列印
 * */
static void PrintfLog(char * fromat,va_list args){
	int d;
	char c,*s;
	while(*fromat)
	{
		switch(*fromat){
			case 's':{
				s = va_arg(args, char *);
				fprintf(loging.logfile,"%s",s);
				break;}
			case 'd':{
				d = va_arg(args, int);
				fprintf(loging.logfile,"%d",d);
				break;}
			case 'c':{
				c = (char)va_arg(args, int);
				fprintf(loging.logfile,"%c",c);
				break;}
			default:{
				if(*fromat!='%'&&*fromat!='\n')
					fprintf(loging.logfile,"%c",*fromat);
				break;}
		}
		fromat++;
	}
	fprintf(loging.logfile,"%s","\n");
}
 
static int initlog(unsigned char loglevel){
	char strdate[30]={0x0};
	LOGSET *logsetting;
	//獲取日誌配置資訊
	if((logsetting=getlogset())==NULL){
		perror("Get Log Set Fail!");
		return -1;
	}
	if((loglevel&(logsetting->loglevel))!=loglevel)
		return -1;
 
	memset(&loging,0,sizeof(LOG));
	//獲取日誌時間
	settime();
	if(strlen(logsetting->filepath)==0){
		char *path=getenv("HOME");
		memcpy(logsetting->filepath,path,strlen(path));
 
		getdate(strdate);
		strcat(strdate,".log");
		strcat(logsetting->filepath,"/");
		strcat(logsetting->filepath,strdate);
	}
	memcpy(loging.filepath,logsetting->filepath,MAXFILEPATH);
	//開啟日誌檔案
	if(loging.logfile==NULL)
		loging.logfile=fopen(loging.filepath,"a+");
	if(loging.logfile==NULL){
		perror("Open Log File Fail!---");
		return -1;
	}
	//寫入日誌級別，日誌時間
	fprintf(loging.logfile,"[%s] [%s] ",LogLevelText[loglevel-1],loging.logtime);
	return 0;
}
 
/*
 *日誌寫入
 * */
int LogWrite(unsigned char loglevel,char *fromat,...)
{
	int  rtv = -1;
	va_list args;
	
	//[為支援多執行緒需要加鎖] pthread_mutex_lock(&mutex_log); //lock. 
	
	do{
		//初始化日誌
		if(initlog(loglevel) != 0)
		{
			rtv = -1;
			break;
		}
		//列印日誌資訊
		va_start(args,fromat);
		PrintfLog(fromat,args);
		va_end(args);
		//檔案刷出
		fflush(loging.logfile);
		//日誌關閉
		if(loging.logfile!=NULL)
			fclose(loging.logfile);
		loging.logfile=NULL;
		rtv = 0;
	}while(0);
	
	//[為支援多執行緒需要加鎖] pthread_mutex_unlock(&mutex_log); //unlock. 
	
	return rtv;
}
 

/** test.c **/
 
#include "stdio.h"
#include "stdlib.h"
#include "log.h"
int main(int argv,char**argc){
	printf("%s\n",argc[0]);
	LogWrite(INFO,"%s","Hello World!");
	LogWrite(DEBUG,"%s","H.e.l.l.o W.o.r.l.d!");
	LogWrite(WARN,"%s","H e l l o W o r l d!");
	LogWrite(ERROR,"%s","Hallo World!");
	return 0;
}
 

path=./log
level=INFO

[INFO] [2021-11-24 22:58:16] Hello World!
[INFO] [2021-11-24 22:58:39] Hello World!
[DEBUG] [2021-11-24 22:58:39] H.e.l.l.o W.o.r.l.d!
[WARN] [2021-11-24 22:58:39] H e l l o W o r l d!
[ERROR] [2021-11-24 22:58:39] Hallo World!
[INFO] [2021-11-24 22:58:48] Hello World!
[DEBUG] [2021-11-24 22:58:48] H.e.l.l.o W.o.r.l.d!
[WARN] [2021-11-24 22:58:48] H e l l o W o r l d!
[ERROR] [2021-11-24 22:58:48] Hallo World!