/*********************************************************************
                                                                  v.1
    fifo_logs.cz
      improved log function for First In, First Out (instead of 
      just truncating the entire file when it reaches a max length)

    Requirments:
      ewtoo derivitive talker

    Installing:
      replace your old log () function (located in glue.c)
      with this one....

    Notes:
      if you have MAX_LOG_SIZE set very high... there
      is a small possiblity that could over write the
      stack length when processing... tho i doubt this
      could realistically happen... its not impossible.
      increaseing STACK_SIZE dramatically is one method
      to make sure all bases are covered...

      the second open() call doesnt use O_SYNC... cause
      it takes about 10 times longer when done syncrously
      im not sure of all the side effects of this from
      operating system to operating system but there shouldnt
      be anything noticable

   Bug Reports:
      send to phypor@benland.muc.edu

    Licences:
      freely distributable and modifiable,
      as long as credit given in appropritate
      places for any distrubitions (be it
      this alone or within another package)

    Warranty:
      non, the author <phypor> is in no way responsible
      for use, misuse, abuse, or any other actions
      misactions, reactions of this code,
      its provided as is.

    Author:
      phypor <phypor@benland.muc.edu>

        "if it breaks you get to keep both pieces"
                                   ~old linux proverb


*********************************************************************/




void            log ( char * filename, char * string )
{
   int             fd;
   int             length;
   char           *oldstack = stack;
   char            path[160];

   memset (path, 0, 160);
   sprintf (path, "logs/%s.log", filename);
   fd = open (path, (O_RDWR | O_CREAT | O_SYNC), (S_IRUSR | S_IWUSR));
   length = lseek (fd, 0, SEEK_END);

   if ((length + strlen (string)) > MAX_LOG_SIZE)
   {
      lseek (fd, 0, SEEK_SET);    /* put file ptr back to beginning of file */
      read (fd, stack, length);   /* read it into stack */
      close (fd);                 /* close it */
      fd = open (path, (O_WRONLY | O_CREAT | O_TRUNC),
                        (S_IRUSR | S_IWUSR));
                                  /* re-open, truncating it */

      stack[length] = '\0';       /* make sure stack is NULL terminated */
      stack += strlen (string);   /* advance stack ptr length of string */

      while (*stack && *stack != '\n')
         stack++;                 /* advance stack to next newline */

      if (*stack)
      {
         stack++;                 /* advance past newline */
         write (fd, stack, strlen (stack));
      }
      stack = oldstack;
   }
   sprintf (stack, "%s - %s\n", sys_time (), string);
   if (!(sys_flags & NO_PRINT_LOG))
      printf (stack);
   write (fd, stack, strlen (stack));
   close (fd);

}