Function cupsFileRead

cups/file.c:1691–1763

 */

ssize_t					/* O - Number of bytes read or -1 on error */
cupsFileRead(cups_file_t *fp,		/* I - CUPS file */
             char        *buf,		/* O - Buffer */
	     size_t      bytes)		/* I - Number of bytes to read */
{
  size_t	total;			/* Total bytes read */
  ssize_t	count;			/* Bytes read */


  DEBUG_printf(("2cupsFileRead(fp=%p, buf=%p, bytes=" CUPS_LLFMT ")", (void *)fp, (void *)buf, CUPS_LLCAST bytes));

 /*
  * Range check input...
  */

  if (!fp || !buf || (fp->mode != 'r' && fp->mode != 's'))
    return (-1);

  if (bytes == 0)
    return (0);

  if (fp->eof)
  {
    DEBUG_puts("5cupsFileRead: End-of-file!");
    return (-1);
  }

 /*
  * Loop until all bytes are read...
  */

  total = 0;
  while (bytes > 0)
  {
    if (fp->ptr >= fp->end)
      if (cups_fill(fp) <= 0)
      {
        DEBUG_printf(("4cupsFileRead: cups_fill() returned -1, total="
	              CUPS_LLFMT, CUPS_LLCAST total));

        if (total > 0)
          return ((ssize_t)total);
	else
	  return (-1);
      }

    count = (ssize_t)(fp->end - fp->ptr);
    if (count > (ssize_t)bytes)
      count = (ssize_t)bytes;

    memcpy(buf, fp->ptr,(size_t) count);
    fp->ptr += count;
    fp->pos += count;

    DEBUG_printf(("4cupsFileRead: pos=" CUPS_LLFMT, CUPS_LLCAST fp->pos));

   /*
    * Update the counts for the last read...