/
InBuffer.cpp
83 lines (73 loc) · 1.5 KB
/
InBuffer.cpp
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// InBuffer.cpp
#include "StdAfx.h"
#include "InBuffer.h"
extern "C"
{
#include "../../../C/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++;
}