/* Nessus
 * Copyright (C) 1998 - 2006 Tenable Network Security, Inc.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2,
 * as published by the Free Software Foundation
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 *
 * Log.c -- manages the logfile of Nessus
 *
 */
 


#include <includes.h>
#include <stdarg.h>
#include "comm.h"
#include "utils.h"
#include "log.h"
#include "corevers.h"


static FILE * log;

#define MAX_LOG_SIZE_MEGS 500 /* 500 Megs */

void rotate_log_file(const char * filename)
{
 char path[1024];
 int  i = 0;
 struct stat st;

 if ( stat(filename, &st) == 0 )
 {
  if ( st.st_size < 1024*1024*MAX_LOG_SIZE_MEGS)
	return;
 }
 else return; /* Could not stat the log file */


 log_close();

 for ( i = 0 ; i < 1024 ; i ++ )
 {
  int e;
  snprintf(path, sizeof(path), "%s.%d", filename, i);
  e = stat(path, &st);
  if ( e < 0 && errno == ENOENT ) break;
 }

 if ( i == 1024 ) return; /* ?? */

 rename(filename, path);
}


/* 
 * initialization of the log file
 */
void 
log_init(filename)
  const char * filename;
{
  rotate_log_file(filename);
  if((!filename)||(!strcmp(filename, "stderr"))){
  	log = stderr;
	dup2(2, 3);
	}
  else
    {
      int fd = open(filename, O_WRONLY|O_CREAT|O_APPEND
#ifdef O_LARGEFILE
	| O_LARGEFILE
#endif
	, 0644);
      if(fd < 0)
      {
       perror("log_init():open ");
       print_error("Could not open the logfile, using stderr\n");
       log = stderr;
      }
      
      if(fd != 3)
      {
      if(dup2(fd, 3) < 0)
      {
        perror("dup2 ");
      }
      close(fd);
      }
      
      log = fdopen(3, "a");
      if(log == NULL)
       {
       perror("fdopen ");
       log = stderr;
       dup2(2, 3);
       }
       
#ifdef _IOLBF
	setvbuf(log, NULL, _IOLBF, 0);
#endif	       
    }
}



void log_close()
{
 if(log != NULL)
 {
  log_write("closing logfile");
  fclose(log);
  log = NULL;
 }
}
 

/*
 * write into the logfile
 * Nothing fancy here...
 */
void 
log_write(const char * str, ...)
{
  va_list param;
  char disp[4096];
  char * tmp;
  
  va_start(param, str);
  vsnprintf(disp, sizeof(disp),str, param);
  va_end(param);  
  
  tmp = disp;
  while((tmp=(char*)strchr(tmp, '\n')) != NULL)
  	tmp[0]=' ';
  
	
  if(log != NULL)
  {
   char timestr[255];
   time_t t;
   
   t = time(NULL);
   tmp = ctime(&t);
  
   timestr[sizeof(timestr) - 1 ] = '\0';
   strncpy(timestr, tmp, sizeof(timestr) - 1);
   timestr[strlen(timestr) - 1 ] = '\0';
   fprintf(log, "[%s][%d] %s\n", timestr, getpid(), disp);
  }
}