COMMON: Only take the md5 of the resource fork data section

Since various apps can modify the type/creator of the files, we can't rely on the header of the resource fork to take the md5. I've therefore also recalculated all of the detector entries (all 5 of them) that use the Mac resource fork code.

svn-id: r55764

2 files changed, 13 insertions, 6 deletions

diff --git a/common/macresman.cpp b/common/macresman.cpp
index fc4e0a55f5..9a50549a9d 100644
--- a/common/macresman.cpp
+++ b/common/macresman.cpp
@@ -83,18 +83,25 @@ bool MacResManager::hasResFork() const {
 	return !_baseFileName.empty() && _mode != kResForkNone;
 }
 
-uint32 MacResManager::getResForkSize() const {
+uint32 MacResManager::getResForkDataSize() const {
 	if (!hasResFork())
 		return 0;
 
-	return _resForkSize;
+	_stream->seek(_resForkOffset + 4);
+	return _stream->readUint32BE();
 }
 
 String MacResManager::computeResForkMD5AsString(uint32 length) const {
 	if (!hasResFork())
 		return String();
 
-	SeekableSubReadStream resForkStream(_stream, _resForkOffset, _resForkOffset + _resForkSize);
+	_stream->seek(_resForkOffset);
+	uint32 dataOffset = _stream->readUint32BE() + _resForkOffset;
+	/* uint32 mapOffset = */ _stream->readUint32BE();
+	uint32 dataLength = _stream->readUint32BE();
+
+
+	SeekableSubReadStream resForkStream(_stream, dataOffset, dataOffset + dataLength);
 	return computeStreamMD5AsString(resForkStream, MIN<uint32>(length, _resForkSize));
 }
 
diff --git a/common/macresman.h b/common/macresman.h
index 4b0aea18f6..1cbebbcf4b 100644
--- a/common/macresman.h
+++ b/common/macresman.h
@@ -134,10 +134,10 @@ public:
 	String getResName(uint32 typeID, uint16 resID) const;
 
 	/**
-	 * Get the size of the resource fork
-	 * @return The size of the resource fork
+	 * Get the size of the data portion of the resource fork
+	 * @return The size of the data portion of the resource fork
 	 */
-	uint32 getResForkSize() const;
+	uint32 getResForkDataSize() const;
 
 	/**
 	 * Calculate the MD5 checksum of the resource fork