// Write data to this stream.
public override void Write(byte[] buffer, int offset, int count)
{
int temp;
if (stream == null)
{
throw new ObjectDisposedException
(S._("Exception_Disposed"));
}
if (mode != CompressionMode.Compress)
{
throw new NotSupportedException(S._("IO_NotSupp_Write"));
}
DeflateStream.ValidateBuffer(buffer, offset, count);
if (!headerDone)
{
// Write the gzip header to the output stream.
stream.WriteByte(0x1F); // Magic number.
stream.WriteByte(0x8B);
stream.WriteByte(0x08); // Compression type.
stream.WriteByte(0x00); // Flags.
int secs = (int)((DateTime.UtcNow.Ticks /
TimeSpan.TicksPerSecond) -
62135596800L);
stream.WriteByte((byte)(secs & 0xFF));
stream.WriteByte((byte)((secs >> 8) & 0xFF));
stream.WriteByte((byte)((secs >> 16) & 0xFF));
stream.WriteByte((byte)((secs >> 24) & 0xFF));
stream.WriteByte(0x00); // Extra flags.
stream.WriteByte(0xFF); // OS type (unknown).
headerDone = true;
}
crc32.Update(buffer, offset, count);
deflater.SetInput(buffer, offset, count);
while (!deflater.IsNeedingInput)
{
temp = deflater.Deflate(buf, 0, buf.Length);
if (temp <= 0)
{
if (!deflater.IsNeedingInput)
{
throw new IOException(S._("IO_Compress_Input"));
}
break;
}
stream.Write(buf, 0, temp);
}
}
// Read data from this stream.
public override int Read(byte[] buffer, int offset, int count)
{
int temp;
if (stream == null)
{
throw new ObjectDisposedException
(S._("Exception_Disposed"));
}
if (mode != CompressionMode.Decompress)
{
throw new NotSupportedException(S._("IO_NotSupp_Read"));
}
DeflateStream.ValidateBuffer(buffer, offset, count);
if (!headerDone)
{
ReadHeader();
}
if (endOfStream)
{
return(0);
}
for (;;)
{
temp = inflater.Inflate(buffer, offset, count);
if (temp > 0)
{
crc32.Update(buffer, offset, temp);
if (inflater.IsFinished)
{
ReadFooter();
}
return(temp);
}
if (inflater.IsNeedingDictionary)
{
throw new IOException
(S._("IO_Decompress_NeedDict"));
}
else if (inflater.IsFinished)
{
ReadFooter();
return(0);
}
else if (inflater.IsNeedingInput)
{
temp = stream.Read(buf, 0, buf.Length);
if (temp <= 0)
{
throw new IOException
(S._("IO_Decompress_Truncated"));
}
inflater.SetInput(buf, 0, temp);
}
else
{
throw new IOException
(S._("IO_Decompress_Invalid"));
}
}
}
