Changeset 52831 in webkit

Timestamp:

Jan 5, 2010 3:08:32 PM (14 years ago)

Author:

yong.li@torchmobile.com

Message:

2010-01-05 Yong Li <​yoli@rim.com>

Reviewed by Darin Adler.

Make PNG image decoder work with segmented SharedBuffer
​https://bugs.webkit.org/show_bug.cgi?id=33213

• platform/image-decoders/ImageDecoder.cpp: (WebCore::ImageDecoder::create):
• platform/image-decoders/ImageDecoder.h: (WebCore::ImageDecoder::ImageDecoder): (WebCore::ImageDecoder::isAllDataReceived): (WebCore::ImageDecoder::setData):
• platform/image-decoders/png/PNGImageDecoder.cpp: (WebCore::PNGImageReader::PNGImageReader): (WebCore::PNGImageReader::close): (WebCore::PNGImageReader::currentBufferSize): (WebCore::PNGImageReader::setComplete): (WebCore::PNGImageReader::decode): (WebCore::PNGImageDecoder::decode): (WebCore::PNGImageDecoder::headerAvailable): (WebCore::PNGImageDecoder::pngComplete):

Location:

trunk/WebCore

Files:

• ChangeLog (modified) (1 diff)
• platform/image-decoders/ImageDecoder.cpp (modified) (2 diffs)
• platform/image-decoders/ImageDecoder.h (modified) (4 diffs)
• platform/image-decoders/png/PNGImageDecoder.cpp (modified) (8 diffs)

trunk/WebCore/ChangeLog

@@ +1 @@
+2010-01-05  Yong Li  <yoli@rim.com>
+
+        Reviewed by Darin Adler.
+
+        Make PNG image decoder work with segmented SharedBuffer
+        https://bugs.webkit.org/show_bug.cgi?id=33213
+
+        * platform/image-decoders/ImageDecoder.cpp:
+        (WebCore::ImageDecoder::create):
+        * platform/image-decoders/ImageDecoder.h:
+        (WebCore::ImageDecoder::ImageDecoder):
+        (WebCore::ImageDecoder::isAllDataReceived):
+        (WebCore::ImageDecoder::setData):
+        * platform/image-decoders/png/PNGImageDecoder.cpp:
+        (WebCore::PNGImageReader::PNGImageReader):
+        (WebCore::PNGImageReader::close):
+        (WebCore::PNGImageReader::currentBufferSize):
+        (WebCore::PNGImageReader::setComplete):
+        (WebCore::PNGImageReader::decode):
+        (WebCore::PNGImageDecoder::decode):
+        (WebCore::PNGImageDecoder::headerAvailable):
+        (WebCore::PNGImageDecoder::pngComplete):
+
 2010-01-05  Adam Barth  <abarth@webkit.org>
 

trunk/WebCore/platform/image-decoders/ImageDecoder.cpp

@@ -1 +1 @@
 /*
  * Copyright (C) 2008-2009 Torch Mobile, Inc.
+ * Copyright (C) Research In Motion Limited 2009-2010. All rights reserved.
  *
  *  This library is free software; you can redistribute it and/or
@@ -35 +36 @@
 #include "XBMImageDecoder.h"
 
+using namespace std;
+
 namespace WebCore {
 
+static unsigned copyFromSharedBuffer(char* buffer, unsigned bufferLength, const SharedBuffer& sharedBuffer, unsigned offset)
+{
+    unsigned bytesExtracted = 0;
+    const char* moreData;
+    while (unsigned moreDataLength = sharedBuffer.getSomeData(moreData, offset)) {
+        unsigned bytesToCopy = min(bufferLength - bytesExtracted, moreDataLength);
+        memcpy(buffer + bytesExtracted, moreData, bytesToCopy);
+        bytesExtracted += bytesToCopy;
+        if (bytesExtracted == bufferLength)
+            break;
+        offset += bytesToCopy;
+    }
+    return bytesExtracted;
+}
+
 ImageDecoder* ImageDecoder::create(const SharedBuffer& data)
 {
+    // XBMs require 8 bytes of info.
+    static const unsigned maxMarkerLength = 8;
+
+    char contents[maxMarkerLength];
+    unsigned length = copyFromSharedBuffer(contents, maxMarkerLength, data, 0);
+
     // We need at least 4 bytes to figure out what kind of image we're dealing with.
-    int length = data.size();
     if (length < 4)
         return 0;
 
-    const unsigned char* uContents = (const unsigned char*)data.data();
-    const char* contents = data.data();
+    const unsigned char* uContents = reinterpret_cast<const unsigned char*>(contents);
 
     // GIFs begin with GIF8(7 or 9).

trunk/WebCore/platform/image-decoders/ImageDecoder.h

@@ -2 +2 @@
  * Copyright (C) 2006 Apple Computer, Inc.  All rights reserved.
  * Copyright (C) 2008-2009 Torch Mobile, Inc.
+ * Copyright (C) Research In Motion Limited 2009-2010. All rights reserved.
  * Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies)
  *
@@ -201 +202 @@
             : m_failed(false)
             , m_sizeAvailable(false)
+            , m_isAllDataReceived(false)
 #if ENABLE(IMAGE_DECODER_DOWN_SAMPLING)
             , m_maxNumPixels(-1)
@@ -219 +221 @@
 
         // All specific decoder plugins must do something with the data they are given.
-        virtual void setData(SharedBuffer* data, bool allDataReceived) { m_data = data; }
+        bool isAllDataReceived() const { return m_isAllDataReceived; }
+        virtual void setData(SharedBuffer* data, bool allDataReceived)
+        {
+            m_data = data;
+            m_isAllDataReceived = allDataReceived;
+        }
 
         // Whether or not the size information has been decoded yet. This default
@@ -327 +334 @@
         IntSize m_size;
         bool m_sizeAvailable;
+        bool m_isAllDataReceived;
     };
 

trunk/WebCore/platform/image-decoders/png/PNGImageDecoder.cpp

@@ -2 +2 @@
  * Copyright (C) 2006 Apple Computer, Inc.
  * Copyright (C) 2007-2009 Torch Mobile, Inc.
+ * Copyright (C) Research In Motion Limited 2009-2010. All rights reserved.
  *
  * Portions are Copyright (C) 2001 mozilla.org
@@ -76 +77 @@
         , m_interlaceBuffer(0)
         , m_hasAlpha(0)
+        , m_hasFinishedDecoding(false)
+        , m_currentBufferSize(0)
     {
         m_png = png_create_read_struct(PNG_LIBPNG_VER_STRING, 0, decodingFailed, decodingWarning);
@@ -93 +96 @@
         m_interlaceBuffer = 0;
         m_readOffset = 0;
-    }
-
-    void decode(const Vector<char>& data, bool sizeOnly)
+        m_hasFinishedDecoding = false;
+    }
+
+    unsigned currentBufferSize() const { return m_currentBufferSize; }
+
+    void setComplete() { m_hasFinishedDecoding = true; }
+
+    void decode(const SharedBuffer& data, bool sizeOnly)
     {
         m_decodingSizeOnly = sizeOnly;
@@ -105 +113 @@
         }
 
-        // Go ahead and assume we consumed all the data.  If we consume less, the
-        // callback will adjust our read offset accordingly.  Do not attempt to adjust the
-        // offset after png_process_data returns.
-        unsigned offset = m_readOffset;
-        unsigned remaining = data.size() - m_readOffset;
-        m_readOffset = data.size();
-        png_process_data(m_png, m_info, (png_bytep)(data.data()) + offset, remaining);
+        PNGImageDecoder* decoder = static_cast<PNGImageDecoder*>(png_get_progressive_ptr(m_png));
+        const char* segment;
+        while (unsigned segmentLength = data.getSomeData(segment, m_readOffset)) {
+            m_readOffset += segmentLength;
+            m_currentBufferSize = m_readOffset;
+            png_process_data(m_png, m_info, reinterpret_cast<png_bytep>(const_cast<char*>(segment)), segmentLength);
+            if ((sizeOnly && decoder->isSizeAvailable()) || m_hasFinishedDecoding)
+                break;
+        }
+        if (!m_hasFinishedDecoding && decoder->isAllDataReceived())
+            decoder->pngComplete();
     }
 
@@ -134 +146 @@
     png_bytep m_interlaceBuffer;
     bool m_hasAlpha;
+    bool m_hasFinishedDecoding;
+    unsigned m_currentBufferSize;
 };
 
@@ -190 +204 @@
         return;
 
-    m_reader->decode(m_data->buffer(), sizeOnly);
+    m_reader->decode(*m_data, sizeOnly);
     
     if (m_failed || (!m_frameBufferCache.isEmpty() && m_frameBufferCache[0].status() == RGBA32Buffer::FrameComplete)) {
@@ -298 +312 @@
     if (reader()->decodingSizeOnly()) {
         // If we only needed the size, halt the reader.     
-        reader()->setReadOffset(m_data->size() - png->buffer_size);
+        reader()->setReadOffset(reader()->currentBufferSize() - png->buffer_size);
         png->buffer_size = 0;
     }
@@ -424 +438 @@
 void PNGImageDecoder::pngComplete()
 {
+    m_reader->setComplete();
+
     if (m_frameBufferCache.isEmpty())
         return;