public ZOutputStream(System.IO.Stream out_Renamed, int level) : base()
{
InitBlock();
this.out_Renamed = out_Renamed;
z.deflateInit(level);
compress = true;
}
public ZlibStream(Stream innerStream)
{
_innerStream = innerStream;
if(_innerStream.CanRead)
{
_in = new ZStream();
int ret = _in.inflateInit();
if (ret != zlibConst.Z_OK)
throw new ZStreamException("Unable to initialize inflate");
_inBuff = new byte[_buffSize];
_in.avail_in = 0;
_in.next_in = _inBuff;
_in.next_in_index = 0;
}
if(_innerStream.CanWrite)
{
_out = new ZStream();
int ret = _out.deflateInit(zlibConst.Z_DEFAULT_COMPRESSION);
if (ret != zlibConst.Z_OK)
throw new ZStreamException("Unable to initialize deflate");
_outBuff = new byte[_buffSize];
_out.next_out = _outBuff;
}
}
public ZInputStream(System.IO.Stream in_Renamed, int level) : base(in_Renamed)
{
InitBlock();
this.in_Renamed = in_Renamed;
z.deflateInit(level);
compress = true;
z.next_in = buf;
z.next_in_index = 0;
z.avail_in = 0;
}
IEnumerable<WebSocketsFrame> IExtension.ApplyOutgoing(NetContext context, WebSocketConnection connection, WebSocketsFrame frame)
{
if (!frame.IsControlFrame && frame.PayloadLength > parent.compressMessagesLargerThanBytes)
{
if (frame.Reserved1)
{
throw new InvalidOperationException("Reserved1 flag is already set; extension conflict?");
}
int headerBytes = 0;
if (outbound == null)
{
outbound = new ZStream();
const int BITS = 12; // 4096 byte outbound buffer (instead of full 32k=15)
outbound.deflateInit(zlibConst.Z_BEST_COMPRESSION, BITS);
headerBytes = 2;
}
BufferStream tmp = null;
var payload = frame.Payload;
payload.Position = 0;
byte[] inBuffer = null, outBuffer = null;
try
{
inBuffer = context.GetBuffer();
outBuffer = context.GetBuffer();
tmp = new BufferStream(context, 0);
outbound.next_out = outBuffer;
outbound.next_in = inBuffer;
int remaining = frame.PayloadLength;
while (remaining > 0)
{
int readCount = payload.Read(inBuffer, 0, inBuffer.Length);
if (readCount <= 0) break;
remaining -= readCount;
outbound.next_in_index = 0;
outbound.avail_in = readCount;
do
{
outbound.next_out_index = 0;
outbound.avail_out = outBuffer.Length;
long priorOut = outbound.total_out;
int err = outbound.deflate(remaining == 0 ? zlibConst.Z_SYNC_FLUSH : zlibConst.Z_NO_FLUSH);
if (err != zlibConst.Z_OK && err != zlibConst.Z_STREAM_END)
throw new ZStreamException("deflating: " + outbound.msg);
int outCount = (int)(outbound.total_out - priorOut);
if (outCount > 0)
{
if (headerBytes == 0)
{
tmp.Write(outBuffer, 0, outCount);
}
else
{
if (outCount < headerBytes)
{
throw new InvalidOperationException("Failed to write entire header");
}
// check the generated header meets our expectations
// CMF is very specific - CM must be 8, and CINFO must be <=7 (for 32k window)
if ((outBuffer[0] & 15) != 8)
{
throw new InvalidOperationException("Zlib CM header was incorrect");
}
if ((outBuffer[0] & 128) != 0) // if msb set, is > 7 - invalid
{
throw new InvalidOperationException("Zlib CINFO header was incorrect");
}
// FLG is less important; FCHECK is irrelevent, FLEVEL doesn't matter; but
// FDICT must be zero, to ensure that we aren't expecting a an initialization dictionary
if ((outBuffer[1] & 32) != 0)
{
throw new InvalidOperationException("Zlib FLG.FDICT header was set (must not be)");
}
// skip the header, and write anything else
outCount -= headerBytes;
if (outCount > 0)
{
tmp.Write(outBuffer, headerBytes, outCount);
}
headerBytes = 0; // all written now
}
}
} while (outbound.avail_in > 0 || outbound.avail_out == 0);
}
if (remaining != 0) throw new EndOfStreamException();
if (headerBytes != 0) throw new InvalidOperationException("Zlib header was not written");
// verify the last 4 bytes, then drop them
tmp.Position = tmp.Length - 4;
NetContext.Fill(tmp, outBuffer, 4);
if (!(outBuffer[0] == 0x00 && outBuffer[1] == 0x00 && outBuffer[2] == 0xFF && outBuffer[3] == 0xFF))
{
throw new InvalidOperationException("expectation failed: 0000FFFF in the tail");
}
if (parent.disableContextTakeover && tmp.Length >= frame.PayloadLength)
{ // compressing it didn't do anything useful; since we're going to discard
// the compression context, we might as well stick with the original data
payload.Position = 0;
payload = null; // so that it doesn't get disposed
}
else
{
// set our final output
tmp.Position = 0;
tmp.SetLength(tmp.Length - 4);
long bytesSaved = frame.PayloadLength - tmp.Length;
frame.Payload = tmp;
frame.PayloadLength = (int)tmp.Length;
frame.Reserved1 = true;
tmp = payload as BufferStream;
parent.RegisterOutboundBytesSaved(bytesSaved);
}
}
#if DEBUG
catch (Exception ex)
{
Debug.WriteLine(ex);
throw;
}
#endif
finally
{
if (outbound != null)
{
outbound.next_out = null;
outbound.next_in = null;
}
if (tmp != null) tmp.Dispose();
if (inBuffer != null) context.Recycle(inBuffer);
if (outBuffer != null) context.Recycle(outBuffer);
if (parent.disableContextTakeover) ClearContext(false, true);
}
}
yield return frame;
}
protected override int InitZlibOperation(ZStream zs)
{
// -MAX_WBITS stands for absense of Zlib header and trailer (needed for GZIP compression and decompression)
return zs.deflateInit(_level, -Zlib.MAX_WBITS);
}
private void init(Stream innerStream)
{
m_stream = innerStream;
if (m_stream.CanRead)
{
m_in = new ZStream();
int ret = m_in.inflateInit();
if (ret != zlibConst.Z_OK)
throw new CompressionFailedException("Unable to initialize zlib for deflate: " + ret);
m_inbuf = new byte[bufsize];
m_in.avail_in = 0;
m_in.next_in = m_inbuf;
m_in.next_in_index = 0;
}
if (m_stream.CanWrite)
{
m_out = new ZStream();
int ret = m_out.deflateInit(zlibConst.Z_DEFAULT_COMPRESSION);
if (ret != zlibConst.Z_OK)
throw new CompressionFailedException("Unable to initialize zlib for inflate: " + ret);
m_outbuf = new byte[bufsize];
m_out.next_out = m_outbuf;
}
}
public static PhpBytes GzEncode(PhpBytes data, int level, int encoding_mode)
{
if ((level < -1) || (level > 9))
{
PhpException.Throw(PhpError.Warning, String.Format("compression level ({0}) must be within -1..9", level));
return null;
}
ZStream zs = new ZStream();
int status = zlibConst.Z_OK;
zs.next_in = data.ReadonlyData;
zs.avail_in = data.Length;
// heuristic for max data length
zs.avail_out = data.Length + data.Length / Zlib.PHP_ZLIB_MODIFIER + 15 + 1;
zs.next_out = new byte[zs.avail_out];
switch (encoding_mode)
{
case (int)ForceConstants.FORCE_GZIP:
if ((status = zs.deflateInit(level, -MAX_WBITS)) != zlibConst.Z_OK)
{
PhpException.Throw(PhpError.Warning, zError(status));
return null;
}
break;
case (int)ForceConstants.FORCE_DEFLATE:
if ((status = zs.deflateInit(level)) != zlibConst.Z_OK)
{
PhpException.Throw(PhpError.Warning, zError(status));
return null;
}
break;
}
status = zs.deflate(zlibConst.Z_FINISH);
if (status != zlibConst.Z_STREAM_END)
{
zs.deflateEnd();
if (status == zlibConst.Z_OK)
{
status = zlibConst.Z_STREAM_ERROR;
}
}
else
{
status = zs.deflateEnd();
}
z_error = zs.msg;
if (status == zlibConst.Z_OK)
{
long output_length = zs.total_out + (encoding_mode == (int)ForceConstants.FORCE_GZIP ? GZIP_HEADER_LENGTH + GZIP_FOOTER_LENGTH : GZIP_HEADER_LENGTH);
long output_offset = GZIP_HEADER_LENGTH;
byte[] output = new byte[output_length];
Buffer.BlockCopy(zs.next_out, 0, output, (int)output_offset, (int)zs.total_out);
// fill the header
output[0] = GZIP_HEADER[0];
output[1] = GZIP_HEADER[1];
output[2] = Z_DEFLATED; // zlib constant (private in ZLIB.NET)
output[3] = 0; // reserved flag bits (this function puts invalid flags in here)
// 4-8 represent time and are set to zero
output[9] = OS_CODE; // php constant
if (encoding_mode == (int)ForceConstants.FORCE_GZIP)
{
var crc_algo = new PHP.Library.CRC32();
byte[] crc = crc_algo.ComputeHash(data.ReadonlyData, 0, data.Length);
crc_algo.Dispose();
output[output_length - 8] = crc[0];
output[output_length - 7] = crc[1];
output[output_length - 6] = crc[2];
output[output_length - 5] = crc[3];
output[output_length - 4] = (byte)(zs.total_in & 0xFF);
output[output_length - 3] = (byte)((zs.total_in >> 8) & 0xFF);
output[output_length - 2] = (byte)((zs.total_in >> 16) & 0xFF);
output[output_length - 1] = (byte)((zs.total_in >> 24) & 0xFF);
}
return new PhpBytes(output);
}
else
{
PhpException.Throw(PhpError.Warning, zError(status));
return null;
}
}
public static PhpBytes GzDeflate(PhpBytes data, int level)
{
if ((level < -1) || (level > 9))
{
PhpException.Throw(PhpError.Warning, String.Format("compression level ({0}) must be within -1..9", level));
return null;
}
ZStream zs = new ZStream();
zs.next_in = data.ReadonlyData;
zs.avail_in = data.Length;
// heuristic for max data length
zs.avail_out = data.Length + data.Length / PHP_ZLIB_MODIFIER + 15 + 1;
zs.next_out = new byte[zs.avail_out];
// -15 omits the header (undocumented feature of zlib)
int status = zs.deflateInit(level, -MAX_WBITS);
if (status == zlibConst.Z_OK)
{
status = zs.deflate(zlibConst.Z_FINISH);
if (status != zlibConst.Z_STREAM_END)
{
zs.deflateEnd();
if (status == zlibConst.Z_OK)
{
status = zlibConst.Z_BUF_ERROR;
}
}
else
{
status = zs.deflateEnd();
}
}
if (status == zlibConst.Z_OK)
{
byte[] result = new byte[zs.total_out];
Buffer.BlockCopy(zs.next_out, 0, result, 0, (int)zs.total_out);
return new PhpBytes(result);
}
else
{
PhpException.Throw(PhpError.Warning, zError(status));
return null;
}
}
/// <summary>
/// Reimplements function from zlib (compress2) that is not present in ZLIB.NET.
/// </summary>
/// <param name="dest">Destination array of bytes. May be trimmed if necessary.</param>
/// <param name="source">Source array of bytes.</param>
/// <param name="level">Level of compression.</param>
/// <returns>Zlib status code.</returns>
private static int ZlibCompress(ref byte[] dest, byte[] source, int level)
{
ZStream stream = new ZStream();
int err;
stream.next_in = source;
stream.avail_in = source.Length;
stream.next_out = dest;
stream.avail_out = dest.Length;
err = stream.deflateInit(level);
if (err != zlibConst.Z_OK) return err;
err = stream.deflate(zlibConst.Z_FINISH);
if (err != zlibConst.Z_STREAM_END)
{
stream.deflateEnd();
return err == zlibConst.Z_OK ? zlibConst.Z_BUF_ERROR : err;
}
if (stream.total_out != dest.Length)
{
byte[] output = new byte[stream.total_out];
Buffer.BlockCopy(stream.next_out, 0, output, 0, (int)stream.total_out);
dest = output;
}
return stream.deflateEnd();
}