Fix errors caused by unsafe conversions to/from size_t

third_party/WebKit/Source/platform/image-decoders/ImageDecoder.cpp

 /*
  * Copyright (C) Research In Motion Limited 2009-2010. All rights reserved.
  *
  *  This library is free software; you can redistribute it and/or
  *  modify it under the terms of the GNU Library General Public
  *  License as published by the Free Software Foundation; either
  *  version 2 of the License, or (at your option) any later version.
  *
  *  This library is distributed in the hope that it will be useful,
  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ skipping 14 matching lines @@
 #include "platform/image-decoders/bmp/BMPImageDecoder.h"
 #include "platform/image-decoders/gif/GIFImageDecoder.h"
 #include "platform/image-decoders/ico/ICOImageDecoder.h"
 #include "platform/image-decoders/jpeg/JPEGImageDecoder.h"
 #include "platform/image-decoders/png/PNGImageDecoder.h"
 #include "platform/image-decoders/webp/WEBPImageDecoder.h"
 #include "wtf/PassOwnPtr.h"
 
 namespace blink {
 
-static unsigned copyFromSharedBuffer(char* buffer, unsigned bufferLength, const SharedBuffer& sharedBuffer, unsigned offset)
+static size_t copyFromSharedBuffer(char* buffer, size_t bufferLength, const SharedBuffer& sharedBuffer, size_t offset)
 {
-    unsigned bytesExtracted = 0;
+    size_t bytesExtracted = 0;
     const char* moreData;
-    while (unsigned moreDataLength = sharedBuffer.getSomeData(moreData, offset)) {
-        unsigned bytesToCopy = std::min(bufferLength - bytesExtracted, moreDataLength);
+    while (size_t moreDataLength = sharedBuffer.getSomeData(moreData, offset)) {
+        size_t bytesToCopy = std::min(bufferLength - bytesExtracted, moreDataLength);
         memcpy(buffer + bytesExtracted, moreData, bytesToCopy);
         bytesExtracted += bytesToCopy;
         if (bytesExtracted == bufferLength)
             break;
         offset += bytesToCopy;
     }
     return bytesExtracted;
 }
 
 inline bool matchesJPEGSignature(char* contents)
@@ skipping 26 matching lines @@
     return !memcmp(contents, "\x00\x00\x02\x00", 4);
 }
 
 inline bool matchesBMPSignature(char* contents)
 {
     return !memcmp(contents, "BM", 2);
 }
 
 PassOwnPtr<ImageDecoder> ImageDecoder::create(const SharedBuffer& data, AlphaOption alphaOption, GammaAndColorProfileOption colorOptions)
 {
-    const unsigned longestSignatureLength = sizeof("RIFF????WEBPVP") - 1;
+    const size_t longestSignatureLength = sizeof("RIFF????WEBPVP") - 1;
     ASSERT(longestSignatureLength == 14);
 
     size_t maxDecodedBytes = Platform::current() ? Platform::current()->maxDecodedImageBytes() : noDecodedImageByteLimit;
 
     char contents[longestSignatureLength];
     if (copyFromSharedBuffer(contents, longestSignatureLength, data, 0) < longestSignatureLength)
         return nullptr;
 
     if (matchesJPEGSignature(contents))
         return adoptPtr(new JPEGImageDecoder(alphaOption, colorOptions, maxDecodedBytes));
@@ skipping 167 matching lines @@
     return m_planes[i];
 }
 
 size_t ImagePlanes::rowBytes(int i) const
 {
     ASSERT((i >= 0) && i < 3);
     return m_rowBytes[i];
 }
 
 } // namespace blink