STDMETHODIMP CLimitedInStream::Read(void *data, UInt32 size, UInt32 *processedSize)
{
if (processedSize)
*processedSize = 0;
if (_virtPos >= _size)
{
// 9.31: Fixed. Windows doesn't return error in ReadFile and IStream->Read in that case.
return S_OK;
// return (_virtPos == _size) ? S_OK: E_FAIL; // ERROR_HANDLE_EOF
}
{
const UInt64 rem = _size - _virtPos;
if (size > rem)
size = (UInt32)rem;
}
UInt64 newPos = _startOffset + _virtPos;
if (newPos != _physPos)
{
_physPos = newPos;
RINOK(SeekToPhys());
}
HRESULT res = _stream->Read(data, size, &size);
if (processedSize)
*processedSize = size;
_physPos += size;
_virtPos += size;
return res;
}
STDMETHODIMP CClusterInStream::Read(void *data, UInt32 size, UInt32 *processedSize)
{
if (processedSize)
*processedSize = 0;
if (_virtPos >= Size)
return S_OK;
if (_curRem == 0)
{
UInt32 blockSize = (UInt32)1 << BlockSizeLog;
UInt32 virtBlock = (UInt32)(_virtPos >> BlockSizeLog);
UInt32 offsetInBlock = (UInt32)_virtPos & (blockSize - 1);
UInt32 phyBlock = Vector[virtBlock];
UInt64 newPos = StartOffset + ((UInt64)phyBlock << BlockSizeLog) + offsetInBlock;
if (newPos != _physPos)
{
_physPos = newPos;
RINOK(SeekToPhys());
}
_curRem = blockSize - offsetInBlock;
for (int i = 1; i < 64 && (virtBlock + i) < (UInt32)Vector.Size() && phyBlock + i == Vector[virtBlock + i]; i++)
_curRem += (UInt32)1 << BlockSizeLog;
UInt64 rem = Size - _virtPos;
if (_curRem > rem)
_curRem = (UInt32)rem;
}
STDMETHODIMP CExtentsStream::Read(void *data, UInt32 size, UInt32 *processedSize)
{
if (processedSize)
*processedSize = 0;
if (_virtPos >= Extents.Back().Virt)
return S_OK;
if (size == 0)
return S_OK;
unsigned left = 0, right = Extents.Size() - 1;
for (;;)
{
unsigned mid = (left + right) / 2;
if (mid == left)
break;
if (_virtPos < Extents[mid].Virt)
right = mid;
else
left = mid;
}
const CSeekExtent &extent = Extents[left];
UInt64 phyPos = extent.Phy + (_virtPos - extent.Virt);
if (_needStartSeek || _phyPos != phyPos)
{
_needStartSeek = false;
_phyPos = phyPos;
RINOK(SeekToPhys());
}
UInt64 rem = Extents[left + 1].Virt - _virtPos;
if (size > rem)
size = (UInt32)rem;
HRESULT res = Stream->Read(data, size, &size);
_phyPos += size;
_virtPos += size;
if (processedSize)
*processedSize = size;
return res;
}
STDMETHODIMP CLimitedCachedInStream::Read(void *data, UInt32 size, UInt32 *processedSize)
{
if (processedSize)
*processedSize = 0;
if (_virtPos >= _size)
{
// 9.31: Fixed. Windows doesn't return error in ReadFile and IStream->Read in that case.
return S_OK;
// return (_virtPos == _size) ? S_OK: E_FAIL; // ERROR_HANDLE_EOF
}
UInt64 rem = _size - _virtPos;
if (rem < size)
size = (UInt32)rem;
UInt64 newPos = _startOffset + _virtPos;
UInt64 offsetInCache = newPos - _cachePhyPos;
HRESULT res = S_OK;
if (newPos >= _cachePhyPos &&
offsetInCache <= _cacheSize &&
size <= _cacheSize - (size_t)offsetInCache)
{
if (size != 0)
memcpy(data, _cache + (size_t)offsetInCache, size);
}
else
{
if (newPos != _physPos)
{
_physPos = newPos;
RINOK(SeekToPhys());
}
res = _stream->Read(data, size, &size);
_physPos += size;
}
if (processedSize)
*processedSize = size;
_virtPos += size;
return res;
}