/// <exception cref="NotSupportedException">The stream must be in decompress mode to read from.</exception>
/// <exception cref="ArgumentNullException"><paramref name="p"/> is <see langword="null" />.</exception>
/// <exception cref="ArgumentOutOfRangeException">length cannot be negative.</exception>
/// <exception cref="ObjectDisposedException">The method cannot be called after the object has been disposed.</exception>
public unsafe int Read(byte *p, int length)
{
if (!CanRead)
{
throw new NotSupportedException($"{nameof(GZipStream)} must be in decompress mode to read from");
}
if (p == null)
{
throw new ArgumentNullException(nameof(p));
}
if (length < 0)
{
throw new ArgumentOutOfRangeException(nameof(length), "length cannot be negative");
}
if (_isDisposed)
{
throw new ObjectDisposedException(nameof(GZipStream));
}
Contract.EndContractBlock();
var exitLoop = false;
_zstream.next_out = p;
_zstream.avail_out = (uint)length;
while (_zstream.avail_out > 0 && exitLoop == false)
{
if (_zstream.avail_in == 0)
{
var readLength = _stream.Read(_tmpBuffer, 0, _tmpBuffer.Length);
_zstream.avail_in = (uint)readLength;
_zstream.next_in = (byte *)_tmpBufferPtr;
}
var result = ZLibNative.inflate(ref _zstream, ZLibFlush.NoFlush);
switch (result)
{
case ZLibReturnCode.StreamEnd:
exitLoop = true;
break;
case ZLibReturnCode.Ok:
break;
case ZLibReturnCode.MemError:
throw new OutOfMemoryException($"ZLib return code: {result}");
default:
throw new Exception($"ZLib return code: {result}");
}
}
return(length - (int)_zstream.avail_out);
}
