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