File indexing completed on 2025-01-19 03:55:55

 /* ============================================================
  *
  * This file is a part of digiKam project
  * https://www.digikam.org
  *
  * Date        : 2008-11-22
  * Description : some workaround functions to read jpeg
  *               files without relying on libjpeg
  *
  * SPDX-FileCopyrightText: 2008 by Patrick Spendrin <ps ml at gmx dot de>
  *
  * SPDX-License-Identifier: GPL-2.0-or-later
  *
  * ============================================================ */
 
 #include "jpegwin.h"
 
 // Qt includes
 
 #include <QFile>
 #include <QByteArray>
 
 namespace Digikam
 {
 
 namespace JPEGUtils
 {
 
 void init_source (j_decompress_ptr /*cinfo*/)
 {
 }
 
 boolean fill_input_buffer (j_decompress_ptr cinfo)
 {
     digikam_source_mgr* const src  = (digikam_source_mgr*) cinfo->src;
 
     // Create a fake EOI marker
 
     src->eoi[0]              = (JOCTET) 0xFF;
     src->eoi[1]              = (JOCTET) JPEG_EOI;
     src->pub.next_input_byte = src->eoi;
     src->pub.bytes_in_buffer = 2;
 
     return true;
 }
 
 void skip_input_data (j_decompress_ptr cinfo, long nbytes)
 {
     digikam_source_mgr* const src = (digikam_source_mgr*) cinfo->src;
 
     if (nbytes > 0)
     {
         while (nbytes > (long) src->pub.bytes_in_buffer)
         {
             nbytes -= (long) src->pub.bytes_in_buffer;
             (void) fill_input_buffer(cinfo);
         }
 
         src->pub.next_input_byte += (size_t) nbytes;
         src->pub.bytes_in_buffer -= (size_t) nbytes;
     }
 }
 
 void term_source (j_decompress_ptr /*cinfo*/)
 {
 }
 
 void jpeg_memory_src (j_decompress_ptr cinfo, const JOCTET* buffer, size_t bufsize)
 {
     digikam_source_mgr* src = 0;
 
     if (cinfo->src == NULL)
     {
         cinfo->src = (struct jpeg_source_mgr*) (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo,
                         JPOOL_PERMANENT,
                         sizeof(digikam_source_mgr));
     }
 
     src                        = (digikam_source_mgr*) cinfo->src;
     src->pub.init_source       = init_source;
     src->pub.fill_input_buffer = fill_input_buffer;
     src->pub.skip_input_data   = skip_input_data;
     src->pub.resync_to_restart = jpeg_resync_to_restart;    // default
     src->pub.term_source       = term_source;
     src->pub.next_input_byte   = buffer;
     src->pub.bytes_in_buffer   = bufsize;
 }
 
 } // namespace JPEGUtils
 
 } // namespace Digikam