4.44 beta

CPP/7zip/Common/InBuffer.cpp

@@ -0,0 +1,80 @@
+// InBuffer.cpp
+
+#include "StdAfx.h"
+
+#include "InBuffer.h"
+
+#include "../../Common/Alloc.h"
+
+CInBuffer::CInBuffer(): 
+  _buffer(0), 
+  _bufferLimit(0), 
+  _bufferBase(0), 
+  _stream(0),
+  _bufferSize(0)
+{}
+
+bool CInBuffer::Create(UInt32 bufferSize)
+{
+  const UInt32 kMinBlockSize = 1;
+  if (bufferSize < kMinBlockSize)
+    bufferSize = kMinBlockSize;
+  if (_bufferBase != 0 && _bufferSize == bufferSize)
+    return true;
+  Free();
+  _bufferSize = bufferSize;
+  _bufferBase = (Byte *)::MidAlloc(bufferSize);
+  return (_bufferBase != 0);
+}
+
+void CInBuffer::Free()
+{
+  ::MidFree(_bufferBase);
+  _bufferBase = 0;
+}
+
+void CInBuffer::SetStream(ISequentialInStream *stream)
+{
+  _stream = stream;
+}
+
+void CInBuffer::Init()
+{
+  _processedSize = 0;
+  _buffer = _bufferBase;
+  _bufferLimit = _buffer;
+  _wasFinished = false;
+  #ifdef _NO_EXCEPTIONS
+  ErrorCode = S_OK;
+  #endif
+}
+
+bool CInBuffer::ReadBlock()
+{
+  #ifdef _NO_EXCEPTIONS
+  if (ErrorCode != S_OK)
+    return false;
+  #endif
+  if (_wasFinished)
+    return false;
+  _processedSize += (_buffer - _bufferBase);
+  UInt32 numProcessedBytes;
+  HRESULT result = _stream->Read(_bufferBase, _bufferSize, &numProcessedBytes);
+  #ifdef _NO_EXCEPTIONS
+  ErrorCode = result;
+  #else
+  if (result != S_OK)
+    throw CInBufferException(result);
+  #endif
+  _buffer = _bufferBase;
+  _bufferLimit = _buffer + numProcessedBytes;
+  _wasFinished = (numProcessedBytes == 0);
+  return (!_wasFinished);
+}
+
+Byte CInBuffer::ReadBlock2()
+{
+  if(!ReadBlock())
+    return 0xFF;
+  return *_buffer++;
+}