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();
}
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 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();
}
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;
}
}
