gecko-dev/image/decoders/nsICODecoder.h

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/* vim:set tw=80 expandtab softtabstop=4 ts=4 sw=4: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef mozilla_image_decoders_nsICODecoder_h
#define mozilla_image_decoders_nsICODecoder_h
#include "nsAutoPtr.h"
#include "Decoder.h"
#include "imgFrame.h"
#include "nsBMPDecoder.h"
#include "nsPNGDecoder.h"
#include "ICOFileHeaders.h"
namespace mozilla {
namespace image {
class RasterImage;
class nsICODecoder : public Decoder
{
public:
explicit nsICODecoder(RasterImage* aImage);
virtual ~nsICODecoder();
// Obtains the width of the icon directory entry
uint32_t GetRealWidth() const
{
return mDirEntry.mWidth == 0 ? 256 : mDirEntry.mWidth;
}
// Obtains the height of the icon directory entry
uint32_t GetRealHeight() const
{
return mDirEntry.mHeight == 0 ? 256 : mDirEntry.mHeight;
}
virtual void WriteInternal(const char* aBuffer, uint32_t aCount) override;
virtual void FinishInternal() override;
virtual nsresult AllocateFrame(const nsIntSize& aTargetSize
/* = nsIntSize() */) override;
protected:
virtual bool NeedsNewFrame() const override;
private:
// Writes to the contained decoder and sets the appropriate errors
// Returns true if there are no errors.
bool WriteToContainedDecoder(const char* aBuffer, uint32_t aCount);
// Processes a single dir entry of the icon resource
void ProcessDirEntry(IconDirEntry& aTarget);
// Sets the hotspot property of if we have a cursor
void SetHotSpotIfCursor();
// Creates a bitmap file header buffer, returns true if successful
bool FillBitmapFileHeaderBuffer(int8_t* bfh);
// Fixes the ICO height to match that of the BIH.
// and also fixes the BIH height to be /2 of what it was.
// See definition for explanation.
// Returns false if invalid information is contained within.
bool FixBitmapHeight(int8_t* bih);
// Fixes the ICO width to match that of the BIH.
// Returns false if invalid information is contained within.
bool FixBitmapWidth(int8_t* bih);
// Extract bitmap info header size count from BMP information header
int32_t ExtractBIHSizeFromBitmap(int8_t* bih);
// Extract bit count from BMP information header
int32_t ExtractBPPFromBitmap(int8_t* bih);
// Calculates the row size in bytes for the AND mask table
uint32_t CalcAlphaRowSize();
// Obtains the number of colors from the BPP, mBPP must be filled in
uint16_t GetNumColors();
uint16_t mBPP; // Stores the images BPP
uint32_t mPos; // Keeps track of the position we have decoded up until
uint16_t mNumIcons; // Stores the number of icons in the ICO file
uint16_t mCurrIcon; // Stores the current dir entry index we are processing
uint32_t mImageOffset; // Stores the offset of the image data we want
uint8_t* mRow; // Holds one raw line of the image
int32_t mCurLine; // Line index of the image that's currently being decoded
uint32_t mRowBytes; // How many bytes of the row were already received
int32_t mOldLine; // Previous index of the line
nsRefPtr<Decoder> mContainedDecoder; // Contains either a BMP or PNG resource
RawAccessFrameRef mRefForContainedDecoder; // Avoid locking off-main-thread
char mDirEntryArray[ICODIRENTRYSIZE]; // Holds the current dir entry buffer
IconDirEntry mDirEntry; // Holds a decoded dir entry
// Holds the potential bytes that can be a PNG signature
char mSignature[PNGSIGNATURESIZE];
// Holds the potential bytes for a bitmap information header
char mBIHraw[40];
// Stores whether or not the icon file we are processing has type 1 (icon)
bool mIsCursor;
// Stores whether or not the contained resource is a PNG
bool mIsPNG;
};
} // namespace image
} // namespace mozilla
#endif // mozilla_image_decoders_nsICODecoder_h