Cancel image loads if decoding failed (attempt #2)

third_party/WebKit/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
@@ skipping 76 matching lines @@
     enum AlphaOption {
         AlphaPremultiplied,
         AlphaNotPremultiplied
     };
 
     enum GammaAndColorProfileOption {
         GammaAndColorProfileApplied,
         GammaAndColorProfileIgnored
     };
 
+    enum class SniffResult {
+        JPEG,
+        PNG,
+        GIF,
+        WEBP,
+        ICO,
+        BMP,
+        InsufficientData,
+        Invalid
+    };
+
+    static SniffResult determineImageType(const char* data, size_t length);
+    static SniffResult determineImageType(const SharedBuffer&);
+    static SniffResult determineImageType(const SegmentReader&);
+
     ImageDecoder(AlphaOption alphaOption, GammaAndColorProfileOption colorOptions, size_t maxDecodedBytes)
         : m_premultiplyAlpha(alphaOption == AlphaPremultiplied)
         , m_ignoreGammaAndColorProfile(colorOptions == 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 std::unique_ptr<ImageDecoder> create(const char* data, size_t length, AlphaOption, GammaAndColorProfileOption);
-    static std::unique_ptr<ImageDecoder> create(const SharedBuffer&, AlphaOption, GammaAndColorProfileOption);
-    static std::unique_ptr<ImageDecoder> create(const SegmentReader&, AlphaOption, GammaAndColorProfileOption);
+    static std::unique_ptr<ImageDecoder> create(SniffResult, AlphaOption, GammaAndColorProfileOption);
 
     virtual String filenameExtension() const = 0;
 
     bool isAllDataReceived() const { return m_isAllDataReceived; }
 
     void setData(PassRefPtr<SegmentReader> data, bool allDataReceived)
     {
         if (m_failed)
             return;
         m_data = data;
@@ skipping 207 matching lines @@
     bool m_failed;
 
 #if USE(QCMSLIB)
     QCMSTransformUniquePtr m_sourceToOutputDeviceColorTransform;
 #endif
 };
 
 } // namespace blink
 
 #endif