Small cleanup on BMPImageReader.cpp

Source/platform/image-decoders/bmp/BMPImageReader.cpp

Index: Source/platform/image-decoders/bmp/BMPImageReader.cpp
diff --git a/Source/platform/image-decoders/bmp/BMPImageReader.cpp b/Source/platform/image-decoders/bmp/BMPImageReader.cpp
index 32dc46d1baaf34f1750f1755dd30027909ab516f..def470893ca10879b67ab942b05041e4fe0fb6bb 100644
--- a/Source/platform/image-decoders/bmp/BMPImageReader.cpp
+++ b/Source/platform/image-decoders/bmp/BMPImageReader.cpp
@@ -96,7 +96,7 @@ bool BMPImageReader::decodeBMP(bool onlySize)
         return false;
 
     // Read and process info header.
-    if ((m_decodedOffset < (m_headerOffset + m_infoHeader.biSize)) && !processInfoHeader())
+    if ((m_decodedOffset < sizeOfHeaderAndInfoHeader()) && !processInfoHeader())
         return false;
 
     // processInfoHeader() set the size, so if that's all we needed, we're done.
@@ -175,7 +175,8 @@ bool BMPImageReader::readInfoHeaderSize()
     // Don't allow the header to overflow (which would be harmless here, but
     // problematic or at least confusing in other places), or to overrun the
     // image data.
-    if (((m_headerOffset + m_infoHeader.biSize) < m_headerOffset) || (m_imgDataOffset && (m_imgDataOffset < (m_headerOffset + m_infoHeader.biSize))))
+    const size_t headerAndInfoHeaderSize = sizeOfHeaderAndInfoHeader();

[Peter Kasting, 2015/02/03 23:56:43]

Nit: Call this |headerEnd|.

[changseok, 2015/02/04 04:10:32]

Done.

+    if ((headerAndInfoHeaderSize < m_headerOffset) || (m_imgDataOffset && (m_imgDataOffset < headerAndInfoHeaderSize)))
         return m_parent->setFailed();
 
     // See if this is a header size we understand:
@@ -423,7 +424,9 @@ bool BMPImageReader::processBitmasks()
 
         // Fail if we don't have enough file space for the bitmasks.
         static const size_t SIZEOF_BITMASKS = 12;

[Peter Kasting, 2015/02/03 23:56:43]

Nit: While here, change to:

        const size_t bitmasksSize = 12;

[changseok, 2015/02/04 04:10:32]

Done.

-        if (((m_headerOffset + m_infoHeader.biSize + SIZEOF_BITMASKS) < (m_headerOffset + m_infoHeader.biSize)) || (m_imgDataOffset && (m_imgDataOffset < (m_headerOffset + m_infoHeader.biSize + SIZEOF_BITMASKS))))
+        const size_t headerAndInfoHeaderSize = sizeOfHeaderAndInfoHeader();
+        const size_t headerInfoHeaderAndBitmasksSize = headerAndInfoHeaderSize + SIZEOF_BITMASKS;

[Peter Kasting, 2015/02/03 23:56:43]

Nit: Call these |headerEnd| and |bitmasksEnd|.

[changseok, 2015/02/04 04:10:32]

Done.

+        if ((headerInfoHeaderAndBitmasksSize < headerAndInfoHeaderSize) || (m_imgDataOffset && (m_imgDataOffset < headerInfoHeaderAndBitmasksSize)))
             return m_parent->setFailed();
 
         // Read bitmasks.
@@ -530,9 +533,11 @@ bool BMPImageReader::processBitmasks()
 bool BMPImageReader::processColorTable()
 {
     size_t tableSizeInBytes = m_infoHeader.biClrUsed * (m_isOS21x ? 3 : 4);
+    size_t headerAndInfoHeaderSize = sizeOfHeaderAndInfoHeader();
+    size_t headerInfoHeaderAndTableSize = headerAndInfoHeaderSize + tableSizeInBytes;

[Peter Kasting, 2015/02/03 23:56:43]

Nit: Make all these const.  Call the new variables |headerEnd| and |tableEnd|.

[changseok, 2015/02/04 04:10:32]

Done.

 
     // Fail if we don't have enough file space for the color table.
-    if (((m_headerOffset + m_infoHeader.biSize + tableSizeInBytes) < (m_headerOffset + m_infoHeader.biSize)) || (m_imgDataOffset && (m_imgDataOffset < (m_headerOffset + m_infoHeader.biSize + tableSizeInBytes))))
+    if ((headerInfoHeaderAndTableSize < headerAndInfoHeaderSize) || (m_imgDataOffset && (m_imgDataOffset < headerInfoHeaderAndTableSize)))
         return m_parent->setFailed();
 
     // Read color table.