gwenview/lib/jpegerrormanager.h

   1 // vim: set tabstop=4 shiftwidth=4 noexpandtab
   2 /*
   3 Gwenview: an image viewer
   4 Copyright 2007 Aurélien Gâteau <aurelien.gateau@free.fr>
   5
   6 This program is free software; you can redistribute it and/or
   7 modify it under the terms of the GNU General Public License
   8 as published by the Free Software Foundation; either version 2
   9 of the License, or (at your option) any later version.
  10
  11 This program is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 GNU General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with this program; if not, write to the Free Software
  18 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  19
  20 */
  21 #ifndef JPEGERRORMANAGER_H
  22 #define JPEGERRORMANAGER_H
  23
  24 #include <setjmp.h>
  25
  26 extern "C" {
  27 #define XMD_H
  28 #include <jpeglib.h>
  29 #undef const
  30 }
  31
  32 namespace Gwenview {
  33
  34 /**
  35  * A simple error manager which overrides jpeg_error_mgr.error_exit to avoid
  36  * calls to exit(). It uses setjmp, which I don't like, but I don't fill like
  37  * introducing exceptions to the code base for now.
  38  *
  39  * In order to use it, give an instance of it to jpeg_decompress_struct.err,
  40  * then call setjmp(errorManager.jmp_buffer)
  41  */
  42 struct JPEGErrorManager : public jpeg_error_mgr {
  43         JPEGErrorManager() : jpeg_error_mgr() {
  44                 jpeg_std_error(this);
  45                 error_exit=errorExitCallBack;
  46         }
  47
  48         jmp_buf jmp_buffer;
  49
  50         static void errorExitCallBack (j_common_ptr cinfo) {
  51                 JPEGErrorManager* myerr = static_cast<JPEGErrorManager*>(cinfo->err);
  52                 char buffer[JMSG_LENGTH_MAX];
  53                 (*cinfo->err->format_message)(cinfo, buffer);
  54                 kWarning() << buffer ;
  55                 longjmp(myerr->jmp_buffer, 1);
  56         }
  57 };
  58
  59 } // namespace
  60
  61 #endif /* JPEGERRORMANAGER_H */