GIF decoding to Index8, unit tests and misusing unit test as benchmark

third_party/WebKit/Source/platform/image-decoders/gif/GIFImageReader.h

 /* -*- Mode: C; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
 /* ***** BEGIN LICENSE BLOCK *****
  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
  *
  * The contents of this file are subject to the Mozilla Public License Version
  * 1.1 (the "License"); you may not use this file except in compliance with
  * the License. You may obtain a copy of the License at
  * http://www.mozilla.org/MPL/
  *
  * Software distributed under the License is distributed on an "AS IS" basis,
@@ skipping 150 matching lines @@
     }
 
     // Set position and number of colors for the RGB table in the data stream.
     void setTablePositionAndSize(size_t position, size_t colors)
     {
         m_position = position;
         m_colors = colors;
     }
     void setDefined() { m_isDefined = true; }
     bool isDefined() const { return m_isDefined; }
+    size_t getPosition() const { return m_position; }
+    size_t getTableSize() const { return m_colors; }
 
     // Build RGBA table using the data stream.
     void buildTable(blink::FastSharedBufferReader*);
     const Table& table() const { return m_table; }
 
 private:
     bool m_isDefined;
     size_t m_position;
     size_t m_colors;
     Table m_table;
@@ skipping 104 matching lines @@
         : m_client(client)
         , m_state(GIFType)
         , m_bytesToConsume(6) // Number of bytes for GIF type, either "GIF87a" or "GIF89a".
         , m_bytesRead(0)
         , m_version(0)
         , m_screenWidth(0)
         , m_screenHeight(0)
         , m_sentSizeToClient(false)
         , m_loopCount(cLoopCountNotSeen)
         , m_parseCompleted(false)
+        , m_backgroundIndex(-1)

[scroggo_chromium, 2016/04/29 19:48:15]

It's a little weird that you initialize this unsigned field to -1.

     {
     }
 
     ~GIFImageReader()
     {
     }
 
     void setData(PassRefPtr<blink::SharedBuffer> data) { m_data = data; }
     bool parse(blink::GIFImageDecoder::GIFParseQuery);
     bool decode(size_t frameIndex);
@@ skipping 17 matching lines @@
 
     const GIFFrameContext* frameContext(size_t index) const
     {
         return index < m_frames.size() ? m_frames[index].get() : 0;
     }
 
     bool parseCompleted() const { return m_parseCompleted; }
 
     void clearDecodeState(size_t index) { m_frames[index]->clearDecodeState(); }
 
+    unsigned backgroundIndex() const { return m_backgroundIndex; }
+
 private:
     bool parseData(size_t dataPosition, size_t len, blink::GIFImageDecoder::GIFParseQuery);
     void setRemainingBytes(size_t);
 
     void addFrameIfNecessary();
     bool currentFrameIsFirstFrame() const
     {
         return m_frames.isEmpty() || (m_frames.size() == 1u && !m_frames[0]->isComplete());
     }
 
     blink::GIFImageDecoder* m_client;
 
     // Parsing state machine.
     GIFState m_state; // Current decoder master state.
     size_t m_bytesToConsume; // Number of bytes to consume for next stage of parsing.
     size_t m_bytesRead; // Number of bytes processed.
 
     // Global (multi-image) state.
     int m_version; // Either 89 for GIF89 or 87 for GIF87.
     unsigned m_screenWidth; // Logical screen width & height.
     unsigned m_screenHeight;
     bool m_sentSizeToClient;
     GIFColorMap m_globalColorMap;
     int m_loopCount; // Netscape specific extension block to control the number of animation loops a GIF renders.
 
     Vector<OwnPtr<GIFFrameContext>> m_frames;
 
     RefPtr<blink::SharedBuffer> m_data;
     bool m_parseCompleted;
+    unsigned m_backgroundIndex;
 };
 
 #endif