Initial checkin

BeefySysLib/CachedDataStream.cpp

@@ -0,0 +1,79 @@
+#include "CachedDataStream.h"
+
+USING_NS_BF;
+
+CachedDataStream::CachedDataStream(DataStream* stream)
+{
+	mStream = stream;
+	mDataPtr = mChunk;
+	mDataEnd = mChunk + CHUNK_SIZE;
+}
+
+CachedDataStream::~CachedDataStream()
+{
+	Flush();
+}
+
+void CachedDataStream::Flush()
+{
+	int cachedBytes = (int)(mDataPtr - mChunk);
+	if (cachedBytes > 0)
+	{
+		mStream->Write(mChunk, cachedBytes);
+		mDataPtr = mChunk;
+	}
+}
+
+bool CachedDataStream::Eof()
+{
+	Flush();
+	return mStream->Eof();
+}
+
+int CachedDataStream::GetSize()
+{
+	Flush();
+	return mStream->GetSize();
+}
+
+void CachedDataStream::Read(void* ptr, int size)
+{
+	Flush();
+	mStream->Read(ptr, size);
+}
+
+void CachedDataStream::Write(void* ptr, int size)
+{
+	while (size > 0)
+	{
+		int cacheLeft = (int)(mDataEnd - mDataPtr);
+		if (cacheLeft == 0)
+		{
+			Flush();
+			continue;
+		}
+
+		int writeBytes = std::min(cacheLeft, size);
+		memcpy(mDataPtr, ptr, writeBytes);
+		ptr = (uint8*)ptr + writeBytes;
+		size -= writeBytes;
+		mDataPtr += writeBytes;
+	}
+}
+
+int CachedDataStream::GetPos()
+{	
+	return mStream->GetPos() + (int)(mDataPtr - mChunk);
+}
+
+void CachedDataStream::Seek(int size)
+{
+	Flush();
+	mStream->Seek(size);
+}
+
+void CachedDataStream::SetPos(int pos)
+{
+	Flush();
+	mStream->SetPos(pos);
+}