The Tor Browser: image/decoders/nsPNGDecoder.h@6474c204b198

Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.

     1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-

     2  *

     3  * This Source Code Form is subject to the terms of the Mozilla Public

     4  * License, v. 2.0. If a copy of the MPL was not distributed with this

     5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

     7 #ifndef nsPNGDecoder_h__

     8 #define nsPNGDecoder_h__

    10 #include "Decoder.h"

    12 #include "gfxTypes.h"

    14 #include "nsCOMPtr.h"

    16 #include "png.h"

    18 #include "qcms.h"

    20 namespace mozilla {

    21 namespace image {

    22 class RasterImage;

    24 class nsPNGDecoder : public Decoder

    25 {

    26 public:

    27   nsPNGDecoder(RasterImage &aImage);

    28   virtual ~nsPNGDecoder();

    30   virtual void InitInternal();

    31   virtual void WriteInternal(const char* aBuffer, uint32_t aCount, DecodeStrategy aStrategy);

    32   virtual Telemetry::ID SpeedHistogram();

    34   void CreateFrame(png_uint_32 x_offset, png_uint_32 y_offset,

    35                    int32_t width, int32_t height,

    36                    gfxImageFormat format);

    37   void EndImageFrame();

    39   // Check if PNG is valid ICO (32bpp RGBA)

    40   // http://blogs.msdn.com/b/oldnewthing/archive/2010/10/22/10079192.aspx

    41   bool IsValidICO() const

    42   {

    43     // If there are errors in the call to png_get_IHDR, the error_callback in

    44     // nsPNGDecoder.cpp is called.  In this error callback we do a longjmp, so

    45     // we need to save the jump buffer here. Oterwise we'll end up without a

    46     // proper callstack.

    47     if (setjmp(png_jmpbuf(mPNG))) {

    48       // We got here from a longjmp call indirectly from png_get_IHDR

    49       return false;

    50     }

    52     png_uint_32

    53         png_width,  // Unused

    54         png_height; // Unused

    56     int png_bit_depth,

    57         png_color_type;

    59     if (png_get_IHDR(mPNG, mInfo, &png_width, &png_height, &png_bit_depth,

    60                      &png_color_type, nullptr, nullptr, nullptr)) {

    62       return ((png_color_type == PNG_COLOR_TYPE_RGB_ALPHA ||

    63                png_color_type == PNG_COLOR_TYPE_RGB) &&

    64               png_bit_depth == 8);

    65     } else {

    66       return false;

    67     }

    68   }

    70 public:

    71   png_structp mPNG;

    72   png_infop mInfo;

    73   nsIntRect mFrameRect;

    74   uint8_t *mCMSLine;

    75   uint8_t *interlacebuf;

    76   qcms_profile *mInProfile;

    77   qcms_transform *mTransform;

    79   gfxImageFormat format;

    81   // For size decodes

    82   uint8_t mSizeBytes[8]; // Space for width and height, both 4 bytes

    83   uint32_t mHeaderBytesRead;

    85   // whether CMS or premultiplied alpha are forced off

    86   uint32_t mCMSMode;

    88   uint8_t mChannels;

    89   bool mFrameHasNoAlpha;

    90   bool mFrameIsHidden;

    91   bool mDisablePremultipliedAlpha;

    93   struct AnimFrameInfo

    94   {

    95     AnimFrameInfo();

    96 #ifdef PNG_APNG_SUPPORTED

    97     AnimFrameInfo(png_structp aPNG, png_infop aInfo);

    98 #endif

   100     FrameBlender::FrameDisposalMethod mDispose;

   101     FrameBlender::FrameBlendMethod mBlend;

   102     int32_t mTimeout;

   103   };

   105   AnimFrameInfo mAnimInfo;

   107   // The number of frames we've finished.

   108   uint32_t mNumFrames;

   110   /*

   111    * libpng callbacks

   112    *

   113    * We put these in the class so that they can access protected members.

   114    */

   115   static void PNGAPI info_callback(png_structp png_ptr, png_infop info_ptr);

   116   static void PNGAPI row_callback(png_structp png_ptr, png_bytep new_row,

   117                                   png_uint_32 row_num, int pass);

   118 #ifdef PNG_APNG_SUPPORTED

   119   static void PNGAPI frame_info_callback(png_structp png_ptr,

   120                                          png_uint_32 frame_num);

   121 #endif

   122   static void PNGAPI end_callback(png_structp png_ptr, png_infop info_ptr);

   123   static void PNGAPI error_callback(png_structp png_ptr,

   124                                     png_const_charp error_msg);

   125   static void PNGAPI warning_callback(png_structp png_ptr,

   126                                       png_const_charp warning_msg);

   128   // This is defined in the PNG spec as an invariant. We use it to

   129   // do manual validation without libpng.

   130   static const uint8_t pngSignatureBytes[];

   131 };

   133 } // namespace image

   134 } // namespace mozilla

   136 #endif // nsPNGDecoder_h__

The Tor Browser / file revision