internal override unsafe bool WriteDataBlock(IntPtr itemHandle, Int32 numBytesToWrite)
{
byte *dataBlock = (byte *)itemHandle;
if (this.m_compressionScheme == CompressionScheme.None)
{
Int32 numBytesWritten = 0;
Int32 remainingBytes = numBytesToWrite;
while (remainingBytes > 0)
{
Int32 *pNumBytesWritten = &numBytesWritten;
bool success = DryadLinqNative.WriteFile(this.m_fhandle,
dataBlock,
(UInt32)remainingBytes,
(IntPtr)pNumBytesWritten,
null);
if (!success)
{
throw new DryadLinqException(DryadLinqErrorCode.WriteFileError,
String.Format(SR.WriteFileError,
Marshal.GetLastWin32Error()));
}
dataBlock += numBytesWritten;
remainingBytes -= numBytesWritten;
}
}
else
{
if (this.m_compressStream == null)
{
if (this.m_compressionScheme == CompressionScheme.Gzip)
{
this.m_compressStream = new GZipStream(this.m_fstream,
CompressionMode.Compress);
}
else
{
throw new DryadLinqException(DryadLinqErrorCode.UnknownCompressionScheme,
SR.UnknownCompressionScheme);
}
}
// YY: Made an extra copy here. Could do better.
byte[] buffer = new byte[numBytesToWrite];
fixed(byte *pBuffer = buffer)
{
DryadLinqUtil.memcpy(dataBlock, pBuffer, numBytesToWrite);
}
this.m_compressStream.Write(buffer, 0, numBytesToWrite);
}
return(true);
}
internal override unsafe bool WriteDataBlock(IntPtr itemHandle, Int32 numBytesToWrite)
{
byte *dataBlock = (byte *)itemHandle;
byte[] buffer = new byte[numBytesToWrite];
fixed(byte *pBuffer = buffer)
{
DryadLinqUtil.memcpy(dataBlock, pBuffer, numBytesToWrite);
}
this.m_stream.Write(buffer, 0, numBytesToWrite);
return(true);
}
internal override unsafe DataBlockInfo ReadDataBlock()
{
DataBlockInfo blockInfo;
blockInfo.DataBlock = (byte *)Marshal.AllocHGlobal(DefaultBuffSize);
blockInfo.ItemHandle = (IntPtr)blockInfo.DataBlock;
byte[] buffer = new byte[DefaultBuffSize];
blockInfo.BlockSize = this.m_stream.Read(buffer, 0, DefaultBuffSize);
fixed(byte *pBuffer = buffer)
{
DryadLinqUtil.memcpy(pBuffer, blockInfo.DataBlock, blockInfo.BlockSize);
}
return(blockInfo);
}
internal override unsafe DataBlockInfo ReadDataBlock()
{
DataBlockInfo blockInfo;
blockInfo.DataBlock = (byte *)Marshal.AllocHGlobal(DefaultBuffSize);
blockInfo.ItemHandle = (IntPtr)blockInfo.DataBlock;
if (this.m_compressionScheme == CompressionScheme.None)
{
Int32 *pBlockSize = &blockInfo.BlockSize;
bool success = DryadLinqNative.ReadFile(this.m_fhandle,
blockInfo.DataBlock,
DefaultBuffSize,
(IntPtr)pBlockSize,
null);
if (!success)
{
throw new DryadLinqException(DryadLinqErrorCode.ReadFileError,
String.Format(SR.ReadFileError,
Marshal.GetLastWin32Error()));
}
}
else
{
if (this.m_compressStream == null)
{
if (this.m_compressionScheme == CompressionScheme.Gzip)
{
this.m_compressStream = new GZipStream(this.m_fstream,
CompressionMode.Decompress);
}
else
{
throw new DryadLinqException(DryadLinqErrorCode.UnknownCompressionScheme,
SR.UnknownCompressionScheme);
}
}
// YY: Made an extra copy here. Could do better.
byte[] buffer = new byte[DefaultBuffSize];
blockInfo.BlockSize = this.m_compressStream.Read(buffer, 0, DefaultBuffSize);
fixed(byte *pBuffer = buffer)
{
DryadLinqUtil.memcpy(pBuffer, blockInfo.DataBlock, blockInfo.BlockSize);
}
}
return(blockInfo);
}
