Moving GraphicsContext and dependencies from core to platform.

Source/platform/image-decoders/ImageDecoder.h

+/*
+ * Copyright (C) 2006 Apple Computer, Inc.  All rights reserved.
+ * Copyright (C) Research In Motion Limited 2009-2010. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``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 APPLE COMPUTER, INC. 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 ImageDecoder_h
+#define ImageDecoder_h
+
+#include "SkColorPriv.h"
+#include "platform/PlatformExport.h"
+#include "platform/PlatformScreen.h"
+#include "platform/SharedBuffer.h"
+#include "platform/graphics/ImageSource.h"
+#include "platform/image-decoders/ImageFrame.h"
+#include "public/platform/Platform.h"
+#include "wtf/Assertions.h"
+#include "wtf/RefPtr.h"
+#include "wtf/text/WTFString.h"
+#include "wtf/Vector.h"
+
+#if USE(QCMSLIB)
+#include "qcms.h"
+#if OS(MACOSX)
+#include <ApplicationServices/ApplicationServices.h>
+#include "platform/graphics/cg/GraphicsContextCG.h"
+#include "wtf/RetainPtr.h"
+#endif
+#endif
+
+namespace WebCore {
+
+// ImageDecoder is a base for all format-specific decoders
+// (e.g. JPEGImageDecoder). This base manages the ImageFrame cache.
+//
+class PLATFORM_EXPORT ImageDecoder {
+    WTF_MAKE_NONCOPYABLE(ImageDecoder); WTF_MAKE_FAST_ALLOCATED;
+public:
+    static const size_t noDecodedImageByteLimit = blink::Platform::noDecodedImageByteLimit;
+
+    ImageDecoder(ImageSource::AlphaOption alphaOption, ImageSource::GammaAndColorProfileOption gammaAndColorProfileOption, size_t maxDecodedBytes)
+        : m_premultiplyAlpha(alphaOption == ImageSource::AlphaPremultiplied)
+        , m_ignoreGammaAndColorProfile(gammaAndColorProfileOption == ImageSource::GammaAndColorProfileIgnored)
+        , m_maxDecodedBytes(maxDecodedBytes)
+        , m_sizeAvailable(false)
+        , m_isAllDataReceived(false)
+        , m_failed(false) { }
+
+    virtual ~ImageDecoder() { }
+
+    // Returns a caller-owned decoder of the appropriate type.  Returns 0 if
+    // we can't sniff a supported type from the provided data (possibly
+    // because there isn't enough data yet).
+    // Sets m_maxDecodedBytes to Platform::maxImageDecodedBytes().
+    static PassOwnPtr<ImageDecoder> create(const SharedBuffer& data, ImageSource::AlphaOption, ImageSource::GammaAndColorProfileOption);
+
+    // Returns a decoder with custom maxDecodedSize.
+    static PassOwnPtr<ImageDecoder> create(const SharedBuffer& data, ImageSource::AlphaOption, ImageSource::GammaAndColorProfileOption, size_t maxDecodedSize);
+
+    virtual String filenameExtension() const = 0;
+
+    bool isAllDataReceived() const { return m_isAllDataReceived; }
+
+    virtual void setData(SharedBuffer* data, bool allDataReceived)
+    {
+        if (m_failed)
+            return;
+        m_data = data;
+        m_isAllDataReceived = allDataReceived;
+    }
+
+    // Lazily-decodes enough of the image to get the size (if possible).
+    // FIXME: Right now that has to be done by each subclass; factor the
+    // decode call out and use it here.
+    virtual bool isSizeAvailable()
+    {
+        return !m_failed && m_sizeAvailable;
+    }
+
+    virtual IntSize size() const { return m_size; }
+
+    // Decoders which downsample images should override this method to
+    // return the actual decoded size.
+    virtual IntSize decodedSize() const { return size(); }
+
+    // This will only differ from size() for ICO (where each frame is a
+    // different icon) or other formats where different frames are different
+    // sizes. This does NOT differ from size() for GIF or WebP, since
+    // decoding GIF or WebP composites any smaller frames against previous
+    // frames to create full-size frames.
+    virtual IntSize frameSizeAtIndex(size_t) const
+    {
+        return size();
+    }
+
+    // Returns whether the size is legal (i.e. not going to result in
+    // overflow elsewhere).  If not, marks decoding as failed.
+    virtual bool setSize(unsigned width, unsigned height)
+    {
+        if (sizeCalculationMayOverflow(width, height))
+            return setFailed();
+        m_size = IntSize(width, height);
+        m_sizeAvailable = true;
+        return true;
+    }
+
+    // Lazily-decodes enough of the image to get the frame count (if
+    // possible), without decoding the individual frames.
+    // FIXME: Right now that has to be done by each subclass; factor the
+    // decode call out and use it here.
+    virtual size_t frameCount() { return 1; }
+
+    virtual int repetitionCount() const { return cAnimationNone; }
+
+    // Decodes as much of the requested frame as possible, and returns an
+    // ImageDecoder-owned pointer.
+    virtual ImageFrame* frameBufferAtIndex(size_t) = 0;
+
+    // Make the best effort guess to check if the requested frame has alpha channel.
+    virtual bool frameHasAlphaAtIndex(size_t) const;
+
+    // Whether or not the frame is fully received.
+    virtual bool frameIsCompleteAtIndex(size_t) const;
+
+    // Duration for displaying a frame in seconds. This method is used by animated images only.
+    virtual float frameDurationAtIndex(size_t) const { return 0; }
+
+    // Number of bytes in the decoded frame requested. Return 0 if not yet decoded.
+    virtual unsigned frameBytesAtIndex(size_t) const;
+
+    void setIgnoreGammaAndColorProfile(bool flag) { m_ignoreGammaAndColorProfile = flag; }
+    bool ignoresGammaAndColorProfile() const { return m_ignoreGammaAndColorProfile; }
+
+    ImageOrientation orientation() const { return m_orientation; }
+
+    enum { iccColorProfileHeaderLength = 128 };
+
+    static bool rgbColorProfile(const char* profileData, unsigned profileLength)
+    {
+        ASSERT_UNUSED(profileLength, profileLength >= iccColorProfileHeaderLength);
+
+        return !memcmp(&profileData[16], "RGB ", 4);
+    }
+
+    static bool inputDeviceColorProfile(const char* profileData, unsigned profileLength)
+    {
+        ASSERT_UNUSED(profileLength, profileLength >= iccColorProfileHeaderLength);
+
+        return !memcmp(&profileData[12], "mntr", 4) || !memcmp(&profileData[12], "scnr", 4);
+    }
+
+#if USE(QCMSLIB)
+    static qcms_profile* qcmsOutputDeviceProfile()
+    {
+        static qcms_profile* outputDeviceProfile = 0;
+
+        static bool qcmsInitialized = false;
+        if (!qcmsInitialized) {
+            qcmsInitialized = true;
+            // FIXME: Add optional ICCv4 support.
+#if OS(MACOSX)
+            RetainPtr<CGColorSpaceRef> monitorColorSpace(AdoptCF, CGDisplayCopyColorSpace(CGMainDisplayID()));
+            CFDataRef iccProfile(CGColorSpaceCopyICCProfile(monitorColorSpace.get()));
+            if (iccProfile) {
+                size_t length = CFDataGetLength(iccProfile);
+                const unsigned char* systemProfile = CFDataGetBytePtr(iccProfile);
+                outputDeviceProfile = qcms_profile_from_memory(systemProfile, length);
+            }
+#else
+            // FIXME: add support for multiple monitors.
+            ColorProfile profile;
+            screenColorProfile(profile);
+            if (!profile.isEmpty())
+                outputDeviceProfile = qcms_profile_from_memory(profile.data(), profile.size());
+#endif
+            if (outputDeviceProfile && qcms_profile_is_bogus(outputDeviceProfile)) {
+                qcms_profile_release(outputDeviceProfile);
+                outputDeviceProfile = 0;
+            }
+            if (!outputDeviceProfile)
+                outputDeviceProfile = qcms_profile_sRGB();
+            if (outputDeviceProfile)
+                qcms_profile_precache_output_transform(outputDeviceProfile);
+        }
+        return outputDeviceProfile;
+    }
+#endif
+
+    // Sets the "decode failure" flag.  For caller convenience (since so
+    // many callers want to return false after calling this), returns false
+    // to enable easy tailcalling.  Subclasses may override this to also
+    // clean up any local data.
+    virtual bool setFailed()
+    {
+        m_failed = true;
+        return false;
+    }
+
+    bool failed() const { return m_failed; }
+
+    // Clears decoded pixel data from all frames except the provided frame.
+    // Callers may pass WTF::kNotFound to clear all frames.
+    // Note: If |m_frameBufferCache| contains only one frame, it won't be cleared.
+    // Returns the number of bytes of frame data actually cleared.
+    virtual size_t clearCacheExceptFrame(size_t);
+
+    // If the image has a cursor hot-spot, stores it in the argument
+    // and returns true. Otherwise returns false.
+    virtual bool hotSpot(IntPoint&) const { return false; }
+
+    virtual void setMemoryAllocator(SkBitmap::Allocator* allocator)
+    {
+        // FIXME: this doesn't work for images with multiple frames.
+        if (m_frameBufferCache.isEmpty()) {
+            m_frameBufferCache.resize(1);
+            m_frameBufferCache[0].setRequiredPreviousFrameIndex(
+                findRequiredPreviousFrame(0, false));
+        }
+        m_frameBufferCache[0].setMemoryAllocator(allocator);
+    }
+
+protected:
+    // Calculates the most recent frame whose image data may be needed in
+    // order to decode frame |frameIndex|, based on frame disposal methods
+    // and |frameRectIsOpaque|, where |frameRectIsOpaque| signifies whether
+    // the rectangle of frame at |frameIndex| is known to be opaque.
+    // If no previous frame's data is required, returns WTF::kNotFound.
+    //
+    // This function requires that the previous frame's
+    // |m_requiredPreviousFrameIndex| member has been set correctly. The
+    // easiest way to ensure this is for subclasses to call this method and
+    // store the result on the frame via setRequiredPreviousFrameIndex()
+    // as soon as the frame has been created and parsed sufficiently to
+    // determine the disposal method; assuming this happens for all frames
+    // in order, the required invariant will hold.
+    //
+    // Image formats which do not use more than one frame do not need to
+    // worry about this; see comments on
+    // ImageFrame::m_requiredPreviousFrameIndex.
+    size_t findRequiredPreviousFrame(size_t frameIndex, bool frameRectIsOpaque);
+
+    virtual void clearFrameBuffer(size_t frameIndex);
+
+    RefPtr<SharedBuffer> m_data; // The encoded data.
+    Vector<ImageFrame, 1> m_frameBufferCache;
+    bool m_premultiplyAlpha;
+    bool m_ignoreGammaAndColorProfile;
+    ImageOrientation m_orientation;
+
+    // The maximum amount of memory a decoded image should require. Ideally,
+    // image decoders should downsample large images to fit under this limit
+    // (and then return the downsampled size from decodedSize()). Ignoring
+    // this limit can cause excessive memory use or even crashes on low-
+    // memory devices.
+    size_t m_maxDecodedBytes;
+
+private:
+    // Some code paths compute the size of the image as "width * height * 4"
+    // and return it as a (signed) int.  Avoid overflow.
+    static bool sizeCalculationMayOverflow(unsigned width, unsigned height)
+    {
+        unsigned long long total_size = static_cast<unsigned long long>(width)
+                                      * static_cast<unsigned long long>(height);
+        return total_size > ((1 << 29) - 1);
+    }
+
+    IntSize m_size;
+    bool m_sizeAvailable;
+    bool m_isAllDataReceived;
+    bool m_failed;
+};
+
+} // namespace WebCore
+
+#endif