CLZF.cs revision e54acca48ba1ab84ac7c693de45ed31ac3f311c2 
1/*
2 * Copyright (c) 2005 Oren J. Maurice <oymaurice@hazorea.org.il>
3 *
4 * Redistribution and use in source and binary forms, with or without modifica-
5 * tion, are permitted provided that the following conditions are met:
6 *
7 *   1.  Redistributions of source code must retain the above copyright notice,
8 *       this list of conditions and the following disclaimer.
9 *
10 *   2.  Redistributions in binary form must reproduce the above copyright
11 *       notice, this list of conditions and the following disclaimer in the
12 *       documentation and/or other materials provided with the distribution.
13 *
14 *   3.  The name of the author may not be used to endorse or promote products
15 *       derived from this software without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
18 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER-
19 * CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO
20 * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE-
21 * CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
22 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
23 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
24 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTH-
25 * ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
26 * OF THE POSSIBILITY OF SUCH DAMAGE.
27 *
28 * Alternatively, the contents of this file may be used under the terms of
29 * the GNU General Public License version 2 (the "GPL"), in which case the
30 * provisions of the GPL are applicable instead of the above. If you wish to
31 * allow the use of your version of this file only under the terms of the
32 * GPL and not to allow others to use your version of this file under the
33 * BSD license, indicate your decision by deleting the provisions above and
34 * replace them with the notice and other provisions required by the GPL. If
35 * you do not delete the provisions above, a recipient may use your version
36 * of this file under either the BSD or the GPL.
37 */
38
39using System;
40
41namespace LZF.NET
42{
43
44	/// <summary>
45	/// Summary description for CLZF.
46	/// </summary>
47	public class CLZF
48	{
49		// CRC32 data & function
50		UInt32 []crc_32_tab = new UInt32[256]
51		{
52			0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419,
53			0x706af48f, 0xe963a535, 0x9e6495a3, 0x0edb8832, 0x79dcb8a4,
54			0xe0d5e91e, 0x97d2d988, 0x09b64c2b, 0x7eb17cbd, 0xe7b82d07,
55			0x90bf1d91, 0x1db71064, 0x6ab020f2, 0xf3b97148, 0x84be41de,
56			0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7, 0x136c9856,
57			0x646ba8c0, 0xfd62f97a, 0x8a65c9ec, 0x14015c4f, 0x63066cd9,
58			0xfa0f3d63, 0x8d080df5, 0x3b6e20c8, 0x4c69105e, 0xd56041e4,
59			0xa2677172, 0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b,
60			0x35b5a8fa, 0x42b2986c, 0xdbbbc9d6, 0xacbcf940, 0x32d86ce3,
61			0x45df5c75, 0xdcd60dcf, 0xabd13d59, 0x26d930ac, 0x51de003a,
62			0xc8d75180, 0xbfd06116, 0x21b4f4b5, 0x56b3c423, 0xcfba9599,
63			0xb8bda50f, 0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924,
64			0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d, 0x76dc4190,
65			0x01db7106, 0x98d220bc, 0xefd5102a, 0x71b18589, 0x06b6b51f,
66			0x9fbfe4a5, 0xe8b8d433, 0x7807c9a2, 0x0f00f934, 0x9609a88e,
67			0xe10e9818, 0x7f6a0dbb, 0x086d3d2d, 0x91646c97, 0xe6635c01,
68			0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e, 0x6c0695ed,
69			0x1b01a57b, 0x8208f4c1, 0xf50fc457, 0x65b0d9c6, 0x12b7e950,
70			0x8bbeb8ea, 0xfcb9887c, 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3,
71			0xfbd44c65, 0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2,
72			0x4adfa541, 0x3dd895d7, 0xa4d1c46d, 0xd3d6f4fb, 0x4369e96a,
73			0x346ed9fc, 0xad678846, 0xda60b8d0, 0x44042d73, 0x33031de5,
74			0xaa0a4c5f, 0xdd0d7cc9, 0x5005713c, 0x270241aa, 0xbe0b1010,
75			0xc90c2086, 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f,
76			0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4, 0x59b33d17,
77			0x2eb40d81, 0xb7bd5c3b, 0xc0ba6cad, 0xedb88320, 0x9abfb3b6,
78			0x03b6e20c, 0x74b1d29a, 0xead54739, 0x9dd277af, 0x04db2615,
79			0x73dc1683, 0xe3630b12, 0x94643b84, 0x0d6d6a3e, 0x7a6a5aa8,
80			0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1, 0xf00f9344,
81			0x8708a3d2, 0x1e01f268, 0x6906c2fe, 0xf762575d, 0x806567cb,
82			0x196c3671, 0x6e6b06e7, 0xfed41b76, 0x89d32be0, 0x10da7a5a,
83			0x67dd4acc, 0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5,
84			0xd6d6a3e8, 0xa1d1937e, 0x38d8c2c4, 0x4fdff252, 0xd1bb67f1,
85			0xa6bc5767, 0x3fb506dd, 0x48b2364b, 0xd80d2bda, 0xaf0a1b4c,
86			0x36034af6, 0x41047a60, 0xdf60efc3, 0xa867df55, 0x316e8eef,
87			0x4669be79, 0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236,
88			0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f, 0xc5ba3bbe,
89			0xb2bd0b28, 0x2bb45a92, 0x5cb36a04, 0xc2d7ffa7, 0xb5d0cf31,
90			0x2cd99e8b, 0x5bdeae1d, 0x9b64c2b0, 0xec63f226, 0x756aa39c,
91			0x026d930a, 0x9c0906a9, 0xeb0e363f, 0x72076785, 0x05005713,
92			0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38, 0x92d28e9b,
93			0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21, 0x86d3d2d4, 0xf1d4e242,
94			0x68ddb3f8, 0x1fda836e, 0x81be16cd, 0xf6b9265b, 0x6fb077e1,
95			0x18b74777, 0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c,
96			0x8f659eff, 0xf862ae69, 0x616bffd3, 0x166ccf45, 0xa00ae278,
97			0xd70dd2ee, 0x4e048354, 0x3903b3c2, 0xa7672661, 0xd06016f7,
98			0x4969474d, 0x3e6e77db, 0xaed16a4a, 0xd9d65adc, 0x40df0b66,
99			0x37d83bf0, 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9,
100			0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, 0xbad03605,
101			0xcdd70693, 0x54de5729, 0x23d967bf, 0xb3667a2e, 0xc4614ab8,
102			0x5d681b02, 0x2a6f2b94, 0xb40bbe37, 0xc30c8ea1, 0x5a05df1b,
103			0x2d02ef8d
104		};
105
106		public UInt32 crc32(UInt32 OldCRC,byte NewData)
107		{
108			return crc_32_tab[(OldCRC & 0xff) ^ NewData] ^ (OldCRC >> 8);
109		}
110
111
112		/// <summary>
113		/// LZF Compressor
114		/// </summary>
115
116		UInt32 HLOG=14;
117		UInt32 HSIZE=(1<<14);
118
119		/*
120		* don't play with this unless you benchmark!
121		* decompression is not dependent on the hash function
122		* the hashing function might seem strange, just believe me
123		* it works ;)
124		*/
125		UInt32 MAX_LIT=(1 <<  5);
126		UInt32 MAX_OFF=(1 << 13);
127		UInt32 MAX_REF=((1 <<  8) + (1 << 3));
128
129		UInt32 FRST(byte[] Array,UInt32 ptr)
130		{
131			return (UInt32)(((Array[ptr]) << 8) | Array[ptr+1]);
132		}
133
134		UInt32 NEXT(UInt32 v,byte[] Array,UInt32 ptr)
135		{
136			return ((v) << 8) | Array[ptr+2];
137		}
138
139		UInt32 IDX(UInt32 h)
140		{
141                	return ((((h ^ (h << 5)) >> (int) (3*8 - HLOG)) - h*5) & (HSIZE - 1));
142		}
143
144		/*
145		* compressed format
146		*
147		* 000LLLLL <L+1>    ; literal
148		* LLLOOOOO oooooooo ; backref L
149		* 111OOOOO LLLLLLLL oooooooo ; backref L+7
150		*
151		*/
152
153		public int lzf_compress (byte[] in_data, int in_len,byte[] out_data, int out_len)
154		{
155			int c;
156			long []htab=new long[1<<14];
157			for (c=0;c<1<<14;c++)
158			{
159				htab[c]=0;
160			}
161
162			long hslot;
163			UInt32 iidx = 0;
164			UInt32 oidx = 0;
165			//byte *in_end  = ip + in_len;
166			//byte *out_end = op + out_len;
167			long reference;
168
169			UInt32 hval = FRST (in_data,iidx);
170			long off;
171			int lit = 0;
172
173			for (;;)
174				{
175				if (iidx < in_len - 2)
176					{
177					hval = NEXT (hval, in_data,iidx);
178					hslot = IDX (hval);
179					reference = htab[hslot];
180					htab[hslot] = (long)iidx;
181
182					if ((off = iidx - reference - 1) < MAX_OFF
183						&& iidx + 4 < in_len
184						&& reference > 0
185						&& in_data[reference+0] == in_data[iidx+0]
186						&& in_data[reference+1] == in_data[iidx+1]
187						&& in_data[reference+2] == in_data[iidx+2]
188						)
189						{
190						/* match found at *reference++ */
191						UInt32 len = 2;
192						UInt32 maxlen = (UInt32)in_len - iidx - len;
193						maxlen = maxlen > MAX_REF ? MAX_REF : maxlen;
194
195						if (oidx + lit + 1 + 3 >= out_len)
196							return 0;
197
198						do
199							len++;
200						while (len < maxlen && in_data[reference+len] == in_data[iidx+len]);
201
202						if (lit!=0)
203							{
204							out_data[oidx++] = (byte)(lit - 1);
205							lit = -lit;
206							do
207								out_data[oidx++] = in_data[iidx+lit];
208							while ((++lit)!=0);
209							}
210
211						len -= 2;
212						iidx++;
213
214						if (len < 7)
215							{
216							out_data[oidx++] = (byte)((off >> 8) + (len << 5));
217							}
218						else
219							{
220							out_data[oidx++] = (byte)((off >> 8) + (  7 << 5));
221							out_data[oidx++] = (byte)(len - 7);
222							}
223
224						out_data[oidx++] = (byte)off;
225
226						iidx += len-1;
227						hval = FRST (in_data,iidx);
228
229						hval = NEXT (hval,in_data, iidx);
230						htab[IDX (hval)] = iidx;
231						iidx++;
232
233						hval = NEXT (hval, in_data,iidx);
234						htab[IDX (hval)] = iidx;
235						iidx++;
236						continue;
237						}
238					}
239				else if (iidx == in_len)
240					break;
241
242				/* one more literal byte we must copy */
243				lit++;
244				iidx++;
245
246				if (lit == MAX_LIT)
247					{
248					if (oidx + 1 + MAX_LIT >= out_len)
249						return 0;
250
251					out_data[oidx++] = (byte)(MAX_LIT - 1);
252					lit = -lit;
253					do
254						out_data[oidx++] = in_data[iidx+lit];
255					while ((++lit)!=0);
256					}
257				}
258
259			if (lit!=0)
260				{
261				if (oidx + lit + 1 >= out_len)
262					return 0;
263
264				out_data[oidx++] = (byte)(lit - 1);
265				lit = -lit;
266				do
267					out_data[oidx++] = in_data[iidx+lit];
268				while ((++lit)!=0);
269				}
270
271			return (int)oidx;
272		}
273
274		/// <summary>
275		/// LZF Decompressor
276		/// </summary>
277		public int lzf_decompress ( byte[] in_data, int in_len, byte[] out_data, int out_len)
278		{
279			UInt32 iidx=0;
280			UInt32 oidx=0;
281
282			do
283				{
284				UInt32 ctrl = in_data[iidx++];
285
286				if (ctrl < (1 << 5)) /* literal run */
287					{
288					ctrl++;
289
290					if (oidx + ctrl > out_len)
291						{
292						//SET_ERRNO (E2BIG);
293						return 0;
294						}
295
296					do
297						out_data[oidx++] = in_data[iidx++];
298					while ((--ctrl)!=0);
299					}
300				else /* back reference */
301					{
302					UInt32 len = ctrl >> 5;
303
304					int reference = (int)(oidx - ((ctrl & 0x1f) << 8) - 1);
305
306					if (len == 7)
307						len += in_data[iidx++];
308
309					reference -= in_data[iidx++];
310
311					if (oidx + len + 2 > out_len)
312						{
313						//SET_ERRNO (E2BIG);
314						return 0;
315						}
316
317					if (reference < 0)
318						{
319						//SET_ERRNO (EINVAL);
320						return 0;
321						}
322
323					out_data[oidx++]=out_data[reference++];
324					out_data[oidx++]=out_data[reference++];
325
326					do
327						out_data[oidx++]=out_data[reference++];
328					while ((--len)!=0);
329					}
330				}
331			while (iidx < in_len);
332
333			return (int)oidx;
334		}
335
336		public CLZF()
337		{
338			//
339			// TODO: Add ructor logic here
340			//
341		}
342	}
343}
344
345