NVNC/zlib.NET/Inflate.cs - net/nvnc - Rivoreo Source Code Repositories

 // Copyright (c) 2006, ComponentAce
 // http://www.componentace.com
 // All rights reserved.

 // Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

 // Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
 // Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
 // Neither the name of ComponentAce nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.
 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

 /*
 Copyright (c) 2000,2001,2002,2003 ymnk, JCraft,Inc. All rights reserved.

 Redistribution and use in source and binary forms, with or without
 modification, are permitted provided that the following conditions are met:

 1. Redistributions of source code must retain the above copyright notice,
 this list of conditions and the following disclaimer.

 2. Redistributions in binary form must reproduce the above copyright
 notice, this list of conditions and the following disclaimer in
 the documentation and/or other materials provided with the distribution.

 3. The names of the authors may not be used to endorse or promote products
 derived from this software without specific prior written permission.

 THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES,
 INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
 FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL JCRAFT,
 INC. OR ANY CONTRIBUTORS TO THIS SOFTWARE BE LIABLE FOR ANY DIRECT, INDIRECT,
 INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
 OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
 EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
 /*
 * This program is based on zlib-1.1.3, so all credit should go authors
 * Jean-loup Gailly(jloup@gzip.org) and Mark Adler(madler@alumni.caltech.edu)
 * and contributors of zlib.
 */
 using System;
 namespace ComponentAce.Compression.Libs.zlib
 {

 	sealed class Inflate
 	{

 		private const int MAX_WBITS = 15; // 32K LZ77 window

 		// preset dictionary flag in zlib header
 		private const int PRESET_DICT = 0x20;

 		internal const int Z_NO_FLUSH = 0;
 		internal const int Z_PARTIAL_FLUSH = 1;
 		internal const int Z_SYNC_FLUSH = 2;
 		internal const int Z_FULL_FLUSH = 3;
 		internal const int Z_FINISH = 4;

 		private const int Z_DEFLATED = 8;

 		private const int Z_OK = 0;
 		private const int Z_STREAM_END = 1;
 		private const int Z_NEED_DICT = 2;
 		private const int Z_ERRNO = - 1;
 		private const int Z_STREAM_ERROR = - 2;
 		private const int Z_DATA_ERROR = - 3;
 		private const int Z_MEM_ERROR = - 4;
 		private const int Z_BUF_ERROR = - 5;
 		private const int Z_VERSION_ERROR = - 6;

 		private const int METHOD = 0; // waiting for method byte
 		private const int FLAG = 1; // waiting for flag byte
 		private const int DICT4 = 2; // four dictionary check bytes to go
 		private const int DICT3 = 3; // three dictionary check bytes to go
 		private const int DICT2 = 4; // two dictionary check bytes to go
 		private const int DICT1 = 5; // one dictionary check byte to go
 		private const int DICT0 = 6; // waiting for inflateSetDictionary
 		private const int BLOCKS = 7; // decompressing blocks
 		private const int CHECK4 = 8; // four check bytes to go
 		private const int CHECK3 = 9; // three check bytes to go
 		private const int CHECK2 = 10; // two check bytes to go
 		private const int CHECK1 = 11; // one check byte to go
 		private const int DONE = 12; // finished check, done
 		private const int BAD = 13; // got an error--stay here

 		internal int mode; // current inflate mode

 		// mode dependent information
 		internal int method; // if FLAGS, method byte

 		// if CHECK, check values to compare
 		internal long[] was = new long[1]; // computed check value
 		internal long need; // stream check value

 		// if BAD, inflateSync's marker bytes count
 		internal int marker;

 		// mode independent information
 		internal int nowrap; // flag for no wrapper
 		internal int wbits; // log2(window size)  (8..15, defaults to 15)

 		internal InfBlocks blocks; // current inflate_blocks state

 		internal int inflateReset(ZStream z)
 		{
 			if (z == null || z.istate == null)
 				return Z_STREAM_ERROR;

 			z.total_in = z.total_out = 0;
 			z.msg = null;
 			z.istate.mode = z.istate.nowrap != 0?BLOCKS:METHOD;
 			z.istate.blocks.reset(z, null);
 			return Z_OK;
 		}

 		internal int inflateEnd(ZStream z)
 		{
 			if (blocks != null)
 				blocks.free(z);
 			blocks = null;
 			//    ZFREE(z, z->state);
 			return Z_OK;
 		}

 		internal int inflateInit(ZStream z, int w)
 		{
 			z.msg = null;
 			blocks = null;

 			// handle undocumented nowrap option (no zlib header or check)
 			nowrap = 0;
 			if (w < 0)
 			{
 				w = - w;
 				nowrap = 1;
 			}

 			// set window size
 			if (w < 8 || w > 15)
 			{
 				inflateEnd(z);
 				return Z_STREAM_ERROR;
 			}
 			wbits = w;

 			z.istate.blocks = new InfBlocks(z, z.istate.nowrap != 0?null:this, 1 << w);

 			// reset state
 			inflateReset(z);
 			return Z_OK;
 		}

 		internal int inflate(ZStream z, int f)
 		{
 			int r;
 			int b;

 			if (z == null || z.istate == null || z.next_in == null)
 				return Z_STREAM_ERROR;
 			f = f == Z_FINISH?Z_BUF_ERROR:Z_OK;
 			r = Z_BUF_ERROR;
 			while (true)
 			{
 				//System.out.println("mode: "+z.istate.mode);
 				switch (z.istate.mode)
 				{

 					case METHOD:

 						if (z.avail_in == 0)
 							return r; r = f;

 						z.avail_in--; z.total_in++;
 						if (((z.istate.method = z.next_in[z.next_in_index++]) & 0xf) != Z_DEFLATED)
 						{
 							z.istate.mode = BAD;
 							z.msg = "unknown compression method";
 							z.istate.marker = 5; // can't try inflateSync
 							break;
 						}
 						if ((z.istate.method >> 4) + 8 > z.istate.wbits)
 						{
 							z.istate.mode = BAD;
 							z.msg = "invalid window size";
 							z.istate.marker = 5; // can't try inflateSync
 							break;
 						}
 						z.istate.mode = FLAG;
 						goto case FLAG;

 					case FLAG:

 						if (z.avail_in == 0)
 							return r; r = f;

 						z.avail_in--; z.total_in++;
 						b = (z.next_in[z.next_in_index++]) & 0xff;

 						if ((((z.istate.method << 8) + b) % 31) != 0)
 						{
 							z.istate.mode = BAD;
 							z.msg = "incorrect header check";
 							z.istate.marker = 5; // can't try inflateSync
 							break;
 						}

 						if ((b & PRESET_DICT) == 0)
 						{
 							z.istate.mode = BLOCKS;
 							break;
 						}
 						z.istate.mode = DICT4;
 						goto case DICT4;

 					case DICT4:

 						if (z.avail_in == 0)
 							return r; r = f;

 						z.avail_in--; z.total_in++;
 						z.istate.need = ((z.next_in[z.next_in_index++] & 0xff) << 24) & unchecked((int) 0xff000000L);
 						z.istate.mode = DICT3;
 						goto case DICT3;

 					case DICT3:

 						if (z.avail_in == 0)
 							return r; r = f;

 						z.avail_in--; z.total_in++;
 						z.istate.need += (((z.next_in[z.next_in_index++] & 0xff) << 16) & 0xff0000L);
 						z.istate.mode = DICT2;
 						goto case DICT2;

 					case DICT2:

 						if (z.avail_in == 0)
 							return r; r = f;

 						z.avail_in--; z.total_in++;
 						z.istate.need += (((z.next_in[z.next_in_index++] & 0xff) << 8) & 0xff00L);
 						z.istate.mode = DICT1;
 						goto case DICT1;

 					case DICT1:

 						if (z.avail_in == 0)
 							return r; r = f;

 						z.avail_in--; z.total_in++;
 						z.istate.need += (z.next_in[z.next_in_index++] & 0xffL);
 						z.adler = z.istate.need;
 						z.istate.mode = DICT0;
 						return Z_NEED_DICT;

 					case DICT0:
 						z.istate.mode = BAD;
 						z.msg = "need dictionary";
 						z.istate.marker = 0; // can try inflateSync
 						return Z_STREAM_ERROR;

 					case BLOCKS:

 						r = z.istate.blocks.proc(z, r);
 						if (r == Z_DATA_ERROR)
 						{
 							z.istate.mode = BAD;
 							z.istate.marker = 0; // can try inflateSync
 							break;
 						}
 						if (r == Z_OK)
 						{
 							r = f;
 						}
 						if (r != Z_STREAM_END)
 						{
 							return r;
 						}
 						r = f;
 						z.istate.blocks.reset(z, z.istate.was);
 						if (z.istate.nowrap != 0)
 						{
 							z.istate.mode = DONE;
 							break;
 						}
 						z.istate.mode = CHECK4;
 						goto case CHECK4;

 					case CHECK4:

 						if (z.avail_in == 0)
 							return r; r = f;

 						z.avail_in--; z.total_in++;
 						z.istate.need = ((z.next_in[z.next_in_index++] & 0xff) << 24) & unchecked((int) 0xff000000L);
 						z.istate.mode = CHECK3;
 						goto case CHECK3;

 					case CHECK3:

 						if (z.avail_in == 0)
 							return r; r = f;

 						z.avail_in--; z.total_in++;
 						z.istate.need += (((z.next_in[z.next_in_index++] & 0xff) << 16) & 0xff0000L);
 						z.istate.mode = CHECK2;
 						goto case CHECK2;

 					case CHECK2:

 						if (z.avail_in == 0)
 							return r; r = f;

 						z.avail_in--; z.total_in++;
 						z.istate.need += (((z.next_in[z.next_in_index++] & 0xff) << 8) & 0xff00L);
 						z.istate.mode = CHECK1;
 						goto case CHECK1;

 					case CHECK1:

 						if (z.avail_in == 0)
 							return r; r = f;

 						z.avail_in--; z.total_in++;
 						z.istate.need += (z.next_in[z.next_in_index++] & 0xffL);

 						if (((int) (z.istate.was[0])) != ((int) (z.istate.need)))
 						{
 							z.istate.mode = BAD;
 							z.msg = "incorrect data check";
 							z.istate.marker = 5; // can't try inflateSync
 							break;
 						}

 						z.istate.mode = DONE;
 						goto case DONE;

 					case DONE:
 						return Z_STREAM_END;

 					case BAD:
 						return Z_DATA_ERROR;

 					default:
 						return Z_STREAM_ERROR;

 				}
 			}
 		}


 		internal int inflateSetDictionary(ZStream z, byte[] dictionary, int dictLength)
 		{
 			int index = 0;
 			int length = dictLength;
 			if (z == null || z.istate == null || z.istate.mode != DICT0)
 				return Z_STREAM_ERROR;

 			if (z._adler.adler32(1L, dictionary, 0, dictLength) != z.adler)
 			{
 				return Z_DATA_ERROR;
 			}

 			z.adler = z._adler.adler32(0, null, 0, 0);

 			if (length >= (1 << z.istate.wbits))
 			{
 				length = (1 << z.istate.wbits) - 1;
 				index = dictLength - length;
 			}
 			z.istate.blocks.set_dictionary(dictionary, index, length);
 			z.istate.mode = BLOCKS;
 			return Z_OK;
 		}

 		private static byte[] mark = new byte[]{(byte) 0, (byte) 0, (byte) SupportClass.Identity(0xff), (byte) SupportClass.Identity(0xff)};

 		internal int inflateSync(ZStream z)
 		{
 			int n; // number of bytes to look at
 			int p; // pointer to bytes
 			int m; // number of marker bytes found in a row
 			long r, w; // temporaries to save total_in and total_out

 			// set up
 			if (z == null || z.istate == null)
 				return Z_STREAM_ERROR;
 			if (z.istate.mode != BAD)
 			{
 				z.istate.mode = BAD;
 				z.istate.marker = 0;
 			}
 			if ((n = z.avail_in) == 0)
 				return Z_BUF_ERROR;
 			p = z.next_in_index;
 			m = z.istate.marker;

 			// search
 			while (n != 0 && m < 4)
 			{
 				if (z.next_in[p] == mark[m])
 				{
 					m++;
 				}
 				else if (z.next_in[p] != 0)
 				{
 					m = 0;
 				}
 				else
 				{
 					m = 4 - m;
 				}
 				p++; n--;
 			}

 			// restore
 			z.total_in += p - z.next_in_index;
 			z.next_in_index = p;
 			z.avail_in = n;
 			z.istate.marker = m;

 			// return no joy or set up to restart on a new block
 			if (m != 4)
 			{
 				return Z_DATA_ERROR;
 			}
 			r = z.total_in; w = z.total_out;
 			inflateReset(z);
 			z.total_in = r; z.total_out = w;
 			z.istate.mode = BLOCKS;
 			return Z_OK;
 		}

 		// Returns true if inflate is currently at the end of a block generated
 		// by Z_SYNC_FLUSH or Z_FULL_FLUSH. This function is used by one PPP
 		// implementation to provide an additional safety check. PPP uses Z_SYNC_FLUSH
 		// but removes the length bytes of the resulting empty stored block. When
 		// decompressing, PPP checks that at the end of input packet, inflate is
 		// waiting for these length bytes.
 		internal int inflateSyncPoint(ZStream z)
 		{
 			if (z == null || z.istate == null || z.istate.blocks == null)
 				return Z_STREAM_ERROR;
 			return z.istate.blocks.sync_point();
 		}
 	}
 }
	// Copyright (c) 2006, ComponentAce
	// http://www.componentace.com
	// All rights reserved.

	// Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

	// Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
	// Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
	// Neither the name of ComponentAce nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.
	// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

	/*
	Copyright (c) 2000,2001,2002,2003 ymnk, JCraft,Inc. All rights reserved.

	Redistribution and use in source and binary forms, with or without
	modification, are permitted provided that the following conditions are met:

	1. Redistributions of source code must retain the above copyright notice,
	this list of conditions and the following disclaimer.

	2. Redistributions in binary form must reproduce the above copyright
	notice, this list of conditions and the following disclaimer in
	the documentation and/or other materials provided with the distribution.

	3. The names of the authors may not be used to endorse or promote products
	derived from this software without specific prior written permission.

	THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES,
	INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
	FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL JCRAFT,
	INC. OR ANY CONTRIBUTORS TO THIS SOFTWARE BE LIABLE FOR ANY DIRECT, INDIRECT,
	INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
	LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
	OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
	LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
	NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
	EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	*/
	/*
	* This program is based on zlib-1.1.3, so all credit should go authors
	* Jean-loup Gailly(jloup@gzip.org) and Mark Adler(madler@alumni.caltech.edu)
	* and contributors of zlib.
	*/
	using System;
	namespace ComponentAce.Compression.Libs.zlib
	{

	sealed class Inflate
	{

	private const int MAX_WBITS = 15; // 32K LZ77 window

	// preset dictionary flag in zlib header
	private const int PRESET_DICT = 0x20;

	internal const int Z_NO_FLUSH = 0;
	internal const int Z_PARTIAL_FLUSH = 1;
	internal const int Z_SYNC_FLUSH = 2;
	internal const int Z_FULL_FLUSH = 3;
	internal const int Z_FINISH = 4;

	private const int Z_DEFLATED = 8;

	private const int Z_OK = 0;
	private const int Z_STREAM_END = 1;
	private const int Z_NEED_DICT = 2;
	private const int Z_ERRNO = - 1;
	private const int Z_STREAM_ERROR = - 2;
	private const int Z_DATA_ERROR = - 3;
	private const int Z_MEM_ERROR = - 4;
	private const int Z_BUF_ERROR = - 5;
	private const int Z_VERSION_ERROR = - 6;

	private const int METHOD = 0; // waiting for method byte
	private const int FLAG = 1; // waiting for flag byte
	private const int DICT4 = 2; // four dictionary check bytes to go
	private const int DICT3 = 3; // three dictionary check bytes to go
	private const int DICT2 = 4; // two dictionary check bytes to go
	private const int DICT1 = 5; // one dictionary check byte to go
	private const int DICT0 = 6; // waiting for inflateSetDictionary
	private const int BLOCKS = 7; // decompressing blocks
	private const int CHECK4 = 8; // four check bytes to go
	private const int CHECK3 = 9; // three check bytes to go
	private const int CHECK2 = 10; // two check bytes to go
	private const int CHECK1 = 11; // one check byte to go
	private const int DONE = 12; // finished check, done
	private const int BAD = 13; // got an error--stay here

	internal int mode; // current inflate mode

	// mode dependent information
	internal int method; // if FLAGS, method byte

	// if CHECK, check values to compare
	internal long[] was = new long[1]; // computed check value
	internal long need; // stream check value

	// if BAD, inflateSync's marker bytes count
	internal int marker;

	// mode independent information
	internal int nowrap; // flag for no wrapper
	internal int wbits; // log2(window size) (8..15, defaults to 15)

	internal InfBlocks blocks; // current inflate_blocks state

	internal int inflateReset(ZStream z)
	{
	if (z == null \|\| z.istate == null)
	return Z_STREAM_ERROR;

	z.total_in = z.total_out = 0;
	z.msg = null;
	z.istate.mode = z.istate.nowrap != 0?BLOCKS:METHOD;
	z.istate.blocks.reset(z, null);
	return Z_OK;
	}

	internal int inflateEnd(ZStream z)
	{
	if (blocks != null)
	blocks.free(z);
	blocks = null;
	// ZFREE(z, z->state);
	return Z_OK;
	}

	internal int inflateInit(ZStream z, int w)
	{
	z.msg = null;
	blocks = null;

	// handle undocumented nowrap option (no zlib header or check)
	nowrap = 0;
	if (w < 0)
	{
	w = - w;
	nowrap = 1;
	}

	// set window size
	if (w < 8 \|\| w > 15)
	{
	inflateEnd(z);
	return Z_STREAM_ERROR;
	}
	wbits = w;

	z.istate.blocks = new InfBlocks(z, z.istate.nowrap != 0?null:this, 1 << w);

	// reset state
	inflateReset(z);
	return Z_OK;
	}

	internal int inflate(ZStream z, int f)
	{
	int r;
	int b;

	if (z == null \|\| z.istate == null \|\| z.next_in == null)
	return Z_STREAM_ERROR;
	f = f == Z_FINISH?Z_BUF_ERROR:Z_OK;
	r = Z_BUF_ERROR;
	while (true)
	{
	//System.out.println("mode: "+z.istate.mode);
	switch (z.istate.mode)
	{

	case METHOD:

	if (z.avail_in == 0)
	return r; r = f;

	z.avail_in--; z.total_in++;
	if (((z.istate.method = z.next_in[z.next_in_index++]) & 0xf) != Z_DEFLATED)
	{
	z.istate.mode = BAD;
	z.msg = "unknown compression method";
	z.istate.marker = 5; // can't try inflateSync
	break;
	}
	if ((z.istate.method >> 4) + 8 > z.istate.wbits)
	{
	z.istate.mode = BAD;
	z.msg = "invalid window size";
	z.istate.marker = 5; // can't try inflateSync
	break;
	}
	z.istate.mode = FLAG;
	goto case FLAG;

	case FLAG:

	if (z.avail_in == 0)
	return r; r = f;

	z.avail_in--; z.total_in++;
	b = (z.next_in[z.next_in_index++]) & 0xff;

	if ((((z.istate.method << 8) + b) % 31) != 0)
	{
	z.istate.mode = BAD;
	z.msg = "incorrect header check";
	z.istate.marker = 5; // can't try inflateSync
	break;
	}

	if ((b & PRESET_DICT) == 0)
	{
	z.istate.mode = BLOCKS;
	break;
	}
	z.istate.mode = DICT4;
	goto case DICT4;

	case DICT4:

	if (z.avail_in == 0)
	return r; r = f;

	z.avail_in--; z.total_in++;
	z.istate.need = ((z.next_in[z.next_in_index++] & 0xff) << 24) & unchecked((int) 0xff000000L);
	z.istate.mode = DICT3;
	goto case DICT3;

	case DICT3:

	if (z.avail_in == 0)
	return r; r = f;

	z.avail_in--; z.total_in++;
	z.istate.need += (((z.next_in[z.next_in_index++] & 0xff) << 16) & 0xff0000L);
	z.istate.mode = DICT2;
	goto case DICT2;

	case DICT2:

	if (z.avail_in == 0)
	return r; r = f;

	z.avail_in--; z.total_in++;
	z.istate.need += (((z.next_in[z.next_in_index++] & 0xff) << 8) & 0xff00L);
	z.istate.mode = DICT1;
	goto case DICT1;

	case DICT1:

	if (z.avail_in == 0)
	return r; r = f;

	z.avail_in--; z.total_in++;
	z.istate.need += (z.next_in[z.next_in_index++] & 0xffL);
	z.adler = z.istate.need;
	z.istate.mode = DICT0;
	return Z_NEED_DICT;

	case DICT0:
	z.istate.mode = BAD;
	z.msg = "need dictionary";
	z.istate.marker = 0; // can try inflateSync
	return Z_STREAM_ERROR;

	case BLOCKS:

	r = z.istate.blocks.proc(z, r);
	if (r == Z_DATA_ERROR)
	{
	z.istate.mode = BAD;
	z.istate.marker = 0; // can try inflateSync
	break;
	}
	if (r == Z_OK)
	{
	r = f;
	}
	if (r != Z_STREAM_END)
	{
	return r;
	}
	r = f;
	z.istate.blocks.reset(z, z.istate.was);
	if (z.istate.nowrap != 0)
	{
	z.istate.mode = DONE;
	break;
	}
	z.istate.mode = CHECK4;
	goto case CHECK4;

	case CHECK4:

	if (z.avail_in == 0)
	return r; r = f;

	z.avail_in--; z.total_in++;
	z.istate.need = ((z.next_in[z.next_in_index++] & 0xff) << 24) & unchecked((int) 0xff000000L);
	z.istate.mode = CHECK3;
	goto case CHECK3;

	case CHECK3:

	if (z.avail_in == 0)
	return r; r = f;

	z.avail_in--; z.total_in++;
	z.istate.need += (((z.next_in[z.next_in_index++] & 0xff) << 16) & 0xff0000L);
	z.istate.mode = CHECK2;
	goto case CHECK2;

	case CHECK2:

	if (z.avail_in == 0)
	return r; r = f;

	z.avail_in--; z.total_in++;
	z.istate.need += (((z.next_in[z.next_in_index++] & 0xff) << 8) & 0xff00L);
	z.istate.mode = CHECK1;
	goto case CHECK1;

	case CHECK1:

	if (z.avail_in == 0)
	return r; r = f;

	z.avail_in--; z.total_in++;
	z.istate.need += (z.next_in[z.next_in_index++] & 0xffL);

	if (((int) (z.istate.was[0])) != ((int) (z.istate.need)))
	{
	z.istate.mode = BAD;
	z.msg = "incorrect data check";
	z.istate.marker = 5; // can't try inflateSync
	break;
	}

	z.istate.mode = DONE;
	goto case DONE;

	case DONE:
	return Z_STREAM_END;

	case BAD:
	return Z_DATA_ERROR;

	default:
	return Z_STREAM_ERROR;

	}
	}
	}


	internal int inflateSetDictionary(ZStream z, byte[] dictionary, int dictLength)
	{
	int index = 0;
	int length = dictLength;
	if (z == null \|\| z.istate == null \|\| z.istate.mode != DICT0)
	return Z_STREAM_ERROR;

	if (z._adler.adler32(1L, dictionary, 0, dictLength) != z.adler)
	{
	return Z_DATA_ERROR;
	}

	z.adler = z._adler.adler32(0, null, 0, 0);

	if (length >= (1 << z.istate.wbits))
	{
	length = (1 << z.istate.wbits) - 1;
	index = dictLength - length;
	}
	z.istate.blocks.set_dictionary(dictionary, index, length);
	z.istate.mode = BLOCKS;
	return Z_OK;
	}

	private static byte[] mark = new byte[]{(byte) 0, (byte) 0, (byte) SupportClass.Identity(0xff), (byte) SupportClass.Identity(0xff)};

	internal int inflateSync(ZStream z)
	{
	int n; // number of bytes to look at
	int p; // pointer to bytes
	int m; // number of marker bytes found in a row
	long r, w; // temporaries to save total_in and total_out

	// set up
	if (z == null \|\| z.istate == null)
	return Z_STREAM_ERROR;
	if (z.istate.mode != BAD)
	{
	z.istate.mode = BAD;
	z.istate.marker = 0;
	}
	if ((n = z.avail_in) == 0)
	return Z_BUF_ERROR;
	p = z.next_in_index;
	m = z.istate.marker;

	// search
	while (n != 0 && m < 4)
	{
	if (z.next_in[p] == mark[m])
	{
	m++;
	}
	else if (z.next_in[p] != 0)
	{
	m = 0;
	}
	else
	{
	m = 4 - m;
	}
	p++; n--;
	}

	// restore
	z.total_in += p - z.next_in_index;
	z.next_in_index = p;
	z.avail_in = n;
	z.istate.marker = m;

	// return no joy or set up to restart on a new block
	if (m != 4)
	{
	return Z_DATA_ERROR;
	}
	r = z.total_in; w = z.total_out;
	inflateReset(z);
	z.total_in = r; z.total_out = w;
	z.istate.mode = BLOCKS;
	return Z_OK;
	}

	// Returns true if inflate is currently at the end of a block generated
	// by Z_SYNC_FLUSH or Z_FULL_FLUSH. This function is used by one PPP
	// implementation to provide an additional safety check. PPP uses Z_SYNC_FLUSH
	// but removes the length bytes of the resulting empty stored block. When
	// decompressing, PPP checks that at the end of input packet, inflate is
	// waiting for these length bytes.
	internal int inflateSyncPoint(ZStream z)
	{
	if (z == null \|\| z.istate == null \|\| z.istate.blocks == null)
	return Z_STREAM_ERROR;
	return z.istate.blocks.sync_point();
	}
	}
	}