sky/engine/platform/image-decoders/bmp/BMPImageDecoder.h

/*
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#ifndef SKY_ENGINE_PLATFORM_IMAGE_DECODERS_BMP_BMPIMAGEDECODER_H_
#define SKY_ENGINE_PLATFORM_IMAGE_DECODERS_BMP_BMPIMAGEDECODER_H_

#include "platform/image-decoders/bmp/BMPImageReader.h"
#include "sky/engine/wtf/OwnPtr.h"

namespace blink {

// This class decodes the BMP image format.
class PLATFORM_EXPORT BMPImageDecoder : public ImageDecoder {
public:
    BMPImageDecoder(ImageSource::AlphaOption, ImageSource::GammaAndColorProfileOption, size_t maxDecodedBytes);

    // ImageDecoder
    virtual String filenameExtension() const override { return "bmp"; }
    virtual void setData(SharedBuffer*, bool allDataReceived) override;
    virtual bool isSizeAvailable() override;
    virtual ImageFrame* frameBufferAtIndex(size_t) override;
    // CAUTION: setFailed() deletes |m_reader|.  Be careful to avoid
    // accessing deleted memory, especially when calling this from inside
    // BMPImageReader!
    virtual bool setFailed() override;

private:
    inline uint32_t readUint32(int offset) const
    {
        return BMPImageReader::readUint32(m_data.get(), m_decodedOffset + offset);
    }

    // Decodes the image.  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(bool onlySize);

    // Decodes the image.  If |onlySize| is true, stops decoding after
    // calculating the image size.  Returns whether decoding succeeded.
    bool decodeHelper(bool onlySize);

    // Processes the file header at the beginning of the data.  Sets
    // |*imgDataOffset| based on the header contents.  Returns true if the
    // file header could be decoded.
    bool processFileHeader(size_t* imgDataOffset);

    // 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 reader used to do most of the BMP decoding.
    OwnPtr<BMPImageReader> m_reader;
};

} // namespace blink

#endif  // SKY_ENGINE_PLATFORM_IMAGE_DECODERS_BMP_BMPIMAGEDECODER_H_