Function cups_raster_read

cups/raster-stream.c:1417–1564

 */

static ssize_t				/* O - Number of bytes read */
cups_raster_read(cups_raster_t *r,	/* I - Raster stream */
                 unsigned char *buf,	/* I - Buffer */
                 size_t        bytes)	/* I - Number of bytes to read */
{
  ssize_t	count,			/* Number of bytes read */
		remaining,		/* Remaining bytes in buffer */
		total;			/* Total bytes read */


  DEBUG_printf(("4cups_raster_read(r=%p, buf=%p, bytes=" CUPS_LLFMT "), offset=" CUPS_LLFMT, (void *)r, (void *)buf, CUPS_LLCAST bytes, CUPS_LLCAST (r->iostart + (ssize_t)(r->bufptr - r->buffer))));

  if (!r->compressed)
    return (cups_raster_io(r, buf, bytes));

 /*
  * Allocate a read buffer as needed...
  */

  count = (ssize_t)(2 * r->header.cupsBytesPerLine);
  if (count < 65536)
    count = 65536;

  if ((size_t)count > r->bufsize)
  {
    ssize_t offset = r->bufptr - r->buffer;
					/* Offset to current start of buffer */
    ssize_t end = r->bufend - r->buffer;/* Offset to current end of buffer */
    unsigned char *rptr;		/* Pointer in read buffer */

    if (r->buffer)
      rptr = realloc(r->buffer, (size_t)count);
    else
      rptr = malloc((size_t)count);

    if (!rptr)
      return (0);

    r->buffer  = rptr;
    r->bufptr  = rptr + offset;
    r->bufend  = rptr + end;
    r->bufsize = (size_t)count;
  }

 /*
  * Loop until we have read everything...
  */

  for (total = 0, remaining = (int)(r->bufend - r->bufptr);
       total < (ssize_t)bytes;
       total += count, buf += count)
  {
    count = (ssize_t)bytes - total;

    DEBUG_printf(("5cups_raster_read: count=" CUPS_LLFMT ", remaining=" CUPS_LLFMT ", buf=%p, bufptr=%p, bufend=%p", CUPS_LLCAST count, CUPS_LLCAST remaining, (void *)buf, (void *)r->bufptr, (void *)r->bufend));

    if (remaining == 0)
    {