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Diffstat (limited to 'Source/WebCore/platform/image-decoders/ico/ICOImageDecoder.h')
| -rw-r--r-- | Source/WebCore/platform/image-decoders/ico/ICOImageDecoder.h | 142 |
1 files changed, 142 insertions, 0 deletions
diff --git a/Source/WebCore/platform/image-decoders/ico/ICOImageDecoder.h b/Source/WebCore/platform/image-decoders/ico/ICOImageDecoder.h new file mode 100644 index 0000000..c2af6a3 --- /dev/null +++ b/Source/WebCore/platform/image-decoders/ico/ICOImageDecoder.h @@ -0,0 +1,142 @@ +/* + * Copyright (c) 2008, 2009, Google Inc. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are + * met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following disclaimer + * in the documentation and/or other materials provided with the + * distribution. + * * Neither the name of Google Inc. nor the names of its + * contributors may be used to endorse or promote products derived from + * this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +#ifndef ICOImageDecoder_h +#define ICOImageDecoder_h + +#include "BMPImageReader.h" + +namespace WebCore { + + class PNGImageDecoder; + + // This class decodes the ICO and CUR image formats. + class ICOImageDecoder : public ImageDecoder { + public: + ICOImageDecoder(ImageSource::AlphaOption, ImageSource::GammaAndColorProfileOption); + virtual ~ICOImageDecoder(); + + // ImageDecoder + virtual String filenameExtension() const { return "ico"; } + virtual void setData(SharedBuffer*, bool allDataReceived); + virtual bool isSizeAvailable(); + virtual IntSize size() const; + virtual IntSize frameSizeAtIndex(size_t) const; + virtual bool setSize(unsigned width, unsigned height); + virtual size_t frameCount(); + virtual RGBA32Buffer* frameBufferAtIndex(size_t); + // CAUTION: setFailed() deletes all readers and decoders. Be careful to + // avoid accessing deleted memory, especially when calling this from + // inside BMPImageReader! + virtual bool setFailed(); + + private: + enum ImageType { + Unknown, + BMP, + PNG, + }; + + struct IconDirectoryEntry { + IntSize m_size; + uint16_t m_bitCount; + uint32_t m_imageOffset; + }; + + // Returns true if |a| is a preferable icon entry to |b|. + // Larger sizes, or greater bitdepths at the same size, are preferable. + static bool compareEntries(const IconDirectoryEntry& a, const IconDirectoryEntry& b); + + inline uint16_t readUint16(int offset) const + { + return BMPImageReader::readUint16(m_data.get(), m_decodedOffset + offset); + } + + inline uint32_t readUint32(int offset) const + { + return BMPImageReader::readUint32(m_data.get(), m_decodedOffset + offset); + } + + // If the desired PNGImageDecoder exists, gives it the appropriate data. + void setDataForPNGDecoderAtIndex(size_t); + + // Decodes the entry at |index|. If |onlySize| is true, stops decoding + // after calculating the image size. If decoding fails but there is no + // more data coming, sets the "decode failure" flag. + void decode(size_t index, bool onlySize); + + // Decodes the directory and directory entries at the beginning of the + // data, and initializes members. Returns true if all decoding + // succeeded. Once this returns true, all entries' sizes are known. + bool decodeDirectory(); + + // Decodes the specified entry. + bool decodeAtIndex(size_t); + + // Processes the ICONDIR at the beginning of the data. Returns true if + // the directory could be decoded. + bool processDirectory(); + + // Processes the ICONDIRENTRY records after the directory. Keeps the + // "best" entry as the one we'll decode. Returns true if the entries + // could be decoded. + bool processDirectoryEntries(); + + // Reads and returns a directory entry from the current offset into + // |data|. + IconDirectoryEntry readDirectoryEntry(); + + // Determines whether the desired entry is a BMP or PNG. Returns true + // if the type could be determined. + ImageType imageTypeAtIndex(size_t); + + // An index into |m_data| representing how much we've already decoded. + // Note that this only tracks data _this_ class decodes; once the + // BMPImageReader takes over this will not be updated further. + size_t m_decodedOffset; + + // The headers for the ICO. + typedef Vector<IconDirectoryEntry> IconDirectoryEntries; + IconDirectoryEntries m_dirEntries; + + // The image decoders for the various frames. + typedef Vector<OwnPtr<BMPImageReader> > BMPReaders; + BMPReaders m_bmpReaders; + typedef Vector<OwnPtr<PNGImageDecoder> > PNGDecoders; + PNGDecoders m_pngDecoders; + + // Valid only while a BMPImageReader is decoding, this holds the size + // for the particular entry being decoded. + IntSize m_frameSize; + }; + +} // namespace WebCore + +#endif |