logfile.h

/*
 * logfunction 
 *
 * Copyright (c) 2020 Rain
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without modifica-
 * tion, are permitted provided that the following conditions are met:
 *
 *   1.  Redistributions of source code must retain the above copyright notice,
 *       this list of conditions and the following disclaimer.
 *
 *   2.  Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in the
 *       documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER-
 * CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO
 * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE-
 * CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTH-
 * ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 * OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * Alternatively, the contents of this file may be used under the terms of
 * the GNU General Public License ("GPL") version 2 or any later version,
 * in which case the provisions of the GPL are applicable instead of
 * the above. If you wish to allow the use of your version of this file
 * only under the terms of the GPL and not to allow others to use your
 * version of this file under the BSD license, indicate your decision
 * by deleting the provisions above and replace them with the notice
 * and other provisions required by the GPL. If you do not delete the
 * provisions above, a recipient may use your version of this file under
 * either the BSD or the GPL.
 */
#ifndef _LOG_FUNCTION_LOGFILE_H_
#define _LOG_FUNCTION_LOGFILE_H_
#include <stdio.h>
#include <string.h>
#ifndef _LOG_BASE_FUNC
#define _LOG_BASE_FUNC
#include <time.h>
static char* __gettime(){
   static char buf[32] = {0};
   time_t t = time(NULL);
   struct tm* local = localtime(&t);
   sprintf(buf, "%04d%02d%02d-%02d:%02d:%02d",
        local->tm_year + 1900, local->tm_mon + 1, local->tm_mday,
        local->tm_hour, local->tm_min, local->tm_sec);
   return buf;
}

#define _LOG(fd, title, ...) {\
    char buff[1024]={0};\
	sprintf(buff, "%s ", __gettime());\
	sprintf(buff, "%s", title);\
	sprintf(buff+strlen(buff), __VA_ARGS__);\
	sprintf(buff+strlen(buff), " line(%d)\n", __LINE__);\
    buff[sizeof(buff)-1]='\0';\
	fprintf(fd, "%s", buff);\
	LogFile::instance()->Write(buff);}

class LogFile 
{
public:
	static LogFile* instance() {
		static LogFile s_log;
		return &s_log;
	}
    char* GetRandLogName(){
	    static char filename[32] = { 0 };
        time_t t = time(NULL);
        struct tm *gmt = localtime(&t);
        sprintf(filename, "log-%04d%02d%02d-%02d%02d%02d.log",
                gmt->tm_year+1900,
                gmt->tm_mon+1,
                gmt->tm_mday,
                gmt->tm_hour,
                gmt->tm_min,
                gmt->tm_sec);     
	    return filename;
	}
	void InitByPath(const char* path){
	    if (path == NULL)
		   return Init(NULL);
	    char filename[512] = {0};
		sprintf(filename, "%s/%s", path, GetRandLogName());
		Init(filename);
	}
	void Init(const char* filename = NULL) {
		if (fd) {fclose(fd);fd = NULL;}
		if (filename) {
			fd = fopen(filename, "w+");
			fseek(fd, 0, SEEK_END);
		}
        else {
            fd = fopen(GetRandLogName(), "w+");
            fseek(fd, 0, SEEK_END);
        }
	}
	void Write(char *buff) {
	    if(!fd) Init(NULL);
      if (fd && buff) {
			  fwrite(buff, 1, strlen(buff), fd);
        //fsync(fd); // syn buffer to disk
		  }
	}
private:
	LogFile():fd(NULL) {}
	~LogFile() {if (fd) fclose(fd);}
	FILE* fd;
};

#include "log.h"
#endif

#endif