Moving GraphicsContext and dependencies from core to platform.

Source/platform/image-decoders/ico/ICOImageDecoder.h

Index: Source/platform/image-decoders/ico/ICOImageDecoder.h
diff --git a/Source/platform/image-decoders/ico/ICOImageDecoder.h b/Source/platform/image-decoders/ico/ICOImageDecoder.h
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index 0000000000000000000000000000000000000000..7f376344114fe7b69dbc6bf1036ee7f9cfa8ead8
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+++ b/Source/platform/image-decoders/ico/ICOImageDecoder.h
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+/*
+ * 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 "platform/image-decoders/bmp/BMPImageReader.h"
+
+namespace WebCore {
+
+class PNGImageDecoder;
+
+// This class decodes the ICO and CUR image formats.
+class PLATFORM_EXPORT ICOImageDecoder : public ImageDecoder {
+public:
+    ICOImageDecoder(ImageSource::AlphaOption, ImageSource::GammaAndColorProfileOption, size_t maxDecodedBytes);
+    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 ImageFrame* 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();
+    virtual bool hotSpot(IntPoint&) const;
+
+private:
+    enum ImageType {
+        Unknown,
+        BMP,
+        PNG,
+    };
+
+    enum FileType {
+        ICON = 1,
+        CURSOR = 2,
+    };
+
+    struct IconDirectoryEntry {
+        IntSize m_size;
+        uint16_t m_bitCount;
+        IntPoint m_hotSpot;
+        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();
+
+    // Stores the hot-spot for |index| in |hotSpot| and returns true,
+    // or returns false if there is none.
+    bool hotSpotAtIndex(size_t index, IntPoint& hotSpot) const;
+
+    // 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;
+
+    // Which type of file (ICO/CUR) this is.
+    FileType m_fileType;
+
+    // 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