DXR is a code search and navigation tool aimed at making sense of large projects. It supports full-text and regex searches as well as structural queries.

Line Code
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147
/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
 *
 * ***** BEGIN LICENSE BLOCK *****
 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
 *
 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 * http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is mozilla.org code.
 *
 * The Initial Developer of the Original Code is
 * Netscape Communications Corporation.
 * Portions created by the Initial Developer are Copyright (C) 2001
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *   Stuart Parmenter <pavlov@netscape.com>
 *   Bobby Holley <bobbyholley@gmail.com>
 *
 * Alternatively, the contents of this file may be used under the terms of
 * either the GNU General Public License Version 2 or later (the "GPL"), or
 * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
 * in which case the provisions of the GPL or the LGPL are applicable instead
 * of those above. If you wish to allow use of your version of this file only
 * under the terms of either the GPL or the LGPL, and not to allow others to
 * use your version of this file under the terms of the MPL, indicate your
 * decision by deleting the provisions above and replace them with the notice
 * and other provisions required by the GPL or the LGPL. If you do not delete
 * the provisions above, a recipient may use your version of this file under
 * the terms of any one of the MPL, the GPL or the LGPL.
 *
 * ***** END LICENSE BLOCK ***** */

#ifndef nsPNGDecoder_h__
#define nsPNGDecoder_h__

#include "Decoder.h"

#include "imgIDecoderObserver.h"
#include "gfxASurface.h"

#include "nsCOMPtr.h"

#include "png.h"

#include "qcms.h"

namespace mozilla {
namespace image {
class RasterImage;

class nsPNGDecoder : public Decoder
{
public:
  nsPNGDecoder(RasterImage &aImage, imgIDecoderObserver* aObserver);
  virtual ~nsPNGDecoder();

  virtual void InitInternal();
  virtual void WriteInternal(const char* aBuffer, PRUint32 aCount);
  virtual Telemetry::ID SpeedHistogram();

  void CreateFrame(png_uint_32 x_offset, png_uint_32 y_offset,
                   PRInt32 width, PRInt32 height,
                   gfxASurface::gfxImageFormat format);
  void SetAnimFrameInfo();

  void EndImageFrame();

  // Check if PNG is valid ICO (32bpp RGBA)
  // http://blogs.msdn.com/b/oldnewthing/archive/2010/10/22/10079192.aspx
  bool IsValidICO() const
  {
    png_uint_32
        png_width,  // Unused
        png_height; // Unused

    int png_bit_depth,
        png_color_type;

    if (png_get_IHDR(mPNG, mInfo, &png_width, &png_height, &png_bit_depth,
                     &png_color_type, NULL, NULL, NULL)) {

      return (png_color_type == PNG_COLOR_TYPE_RGB_ALPHA &&
              png_bit_depth == 8);
    } else {
      return false;
    }
  }

public:
  png_structp mPNG;
  png_infop mInfo;
  nsIntRect mFrameRect;
  PRUint8 *mCMSLine;
  PRUint8 *interlacebuf;
  PRUint8 *mImageData;
  qcms_profile *mInProfile;
  qcms_transform *mTransform;

  gfxASurface::gfxImageFormat format;

  // For size decodes
  PRUint8 *mHeaderBuf;
  PRUint32 mHeaderBytesRead;

  PRUint8 mChannels;
  bool mFrameHasNoAlpha;
  bool mFrameIsHidden;

  // whether CMS or premultiplied alpha are forced off
  PRUint32 mCMSMode;
  bool mDisablePremultipliedAlpha;
  
  /*
   * libpng callbacks
   *
   * We put these in the class so that they can access protected members.
   */
  static void PNGAPI info_callback(png_structp png_ptr, png_infop info_ptr);
  static void PNGAPI row_callback(png_structp png_ptr, png_bytep new_row,
                                  png_uint_32 row_num, int pass);
#ifdef PNG_APNG_SUPPORTED
  static void PNGAPI frame_info_callback(png_structp png_ptr,
                                         png_uint_32 frame_num);
#endif
  static void PNGAPI end_callback(png_structp png_ptr, png_infop info_ptr);
  static void PNGAPI error_callback(png_structp png_ptr,
                                    png_const_charp error_msg);
  static void PNGAPI warning_callback(png_structp png_ptr,
                                      png_const_charp warning_msg);

  // This is defined in the PNG spec as an invariant. We use it to
  // do manual validation without libpng.
  static const PRUint8 pngSignatureBytes[];
};

} // namespace image
} // namespace mozilla

#endif // nsPNGDecoder_h__