Initial commit

engine/core/resizeStream.cc

@@ -0,0 +1,139 @@
+//-----------------------------------------------------------------------------
+// Torque Game Engine
+// Copyright (C) GarageGames.com, Inc.
+//-----------------------------------------------------------------------------
+
+#include "core/resizeStream.h"
+
+ResizeFilterStream::ResizeFilterStream()
+ : m_pStream(NULL),
+   m_startOffset(0),
+   m_streamLen(0),
+   m_currOffset(0)
+{
+   //
+}
+
+ResizeFilterStream::~ResizeFilterStream()
+{
+   detachStream();
+}
+
+bool ResizeFilterStream::attachStream(Stream* io_pSlaveStream)
+{
+   AssertFatal(io_pSlaveStream != NULL, "NULL Slave stream?");
+
+   m_pStream     = io_pSlaveStream;
+   m_startOffset = 0;
+   m_streamLen   = m_pStream->getStreamSize();
+   m_currOffset  = 0;
+   setStatus(EOS);
+   return true;
+}
+
+void ResizeFilterStream::detachStream()
+{
+   m_pStream     = NULL;
+   m_startOffset = 0;
+   m_streamLen   = 0;
+   m_currOffset  = 0;
+   setStatus(Closed);
+}
+
+Stream* ResizeFilterStream::getStream()
+{
+   return m_pStream;
+}
+
+bool ResizeFilterStream::setStreamOffset(const U32 in_startOffset, const U32 in_streamLen)
+{
+   AssertFatal(m_pStream != NULL, "stream not attached!");
+   if (m_pStream == NULL)
+      return false;
+
+   U32 start  = in_startOffset;
+   U32 end    = in_startOffset + in_streamLen;
+   U32 actual = m_pStream->getStreamSize();
+
+   if (start >= actual || end > actual)
+      return false;
+
+   m_startOffset = start;
+   m_streamLen   = in_streamLen;
+   m_currOffset  = 0;
+
+   if (m_streamLen != 0)
+      setStatus(Ok);
+   else
+      setStatus(EOS);
+
+   return true;
+}
+
+U32 ResizeFilterStream::getPosition() const
+{
+   AssertFatal(m_pStream != NULL, "Error, stream not attached");
+   if (m_pStream == NULL)
+      return 0;
+
+   return m_currOffset;
+}
+
+bool ResizeFilterStream::setPosition(const U32 in_newPosition)
+{
+   AssertFatal(m_pStream != NULL, "Error, stream not attached");
+   if (m_pStream == NULL)
+      return false;
+
+   if (in_newPosition < m_streamLen) {
+      m_currOffset = in_newPosition;
+      return true;
+   } else {
+      m_currOffset = m_streamLen;
+      return false;
+   }
+}
+
+U32 ResizeFilterStream::getStreamSize()
+{
+   AssertFatal(m_pStream != NULL, "Error, stream not attached");
+
+   return m_streamLen;
+}
+
+bool ResizeFilterStream::_read(const U32 in_numBytes, void* out_pBuffer)
+{
+   AssertFatal(m_pStream != NULL, "Error, stream not attached");
+
+   if (in_numBytes == 0)
+      return true;
+
+   AssertFatal(out_pBuffer != NULL, "Invalid output buffer");
+   if (getStatus() == Closed) {
+      AssertFatal(false, "Attempted read from closed stream");
+      return false;
+   }
+
+   U32 savePosition = m_pStream->getPosition();
+   if (m_pStream->setPosition(m_startOffset + m_currOffset) == false)
+      return false;
+
+   U32 actualSize = in_numBytes;
+   U32 position   = m_startOffset + m_currOffset;
+   if (in_numBytes + position > m_startOffset + m_streamLen)
+      actualSize = m_streamLen - (position - m_startOffset);
+
+   if (actualSize == 0) {
+      setStatus(EOS);
+      return false;
+   }
+
+   bool success = m_pStream->read(actualSize, out_pBuffer);
+   m_currOffset += actualSize;
+
+   setStatus(m_pStream->getStatus());
+
+   m_pStream->setPosition(savePosition);
+   return success;
+}
+