[ViewVC] Diff of: cvs/liblzf/lzf

Comparing liblzf/lzf_c.c (file contents):
Revision 1.9 by root, Tue Mar 8 19:59:52 2005 UTC vs.
Revision 1.29 by root, Fri Nov 30 10:35:02 2007 UTC

…		…
1	/*	1	/*
2	* Copyright (c) 2000-2005 Marc Alexander Lehmann <schmorp@schmorp.de>	2	* Copyright (c) 2000-2007 Marc Alexander Lehmann <schmorp@schmorp.de>
3	*	3	*
4	* Redistribution and use in source and binary forms, with or without modifica-	4	* Redistribution and use in source and binary forms, with or without modifica-
5	* tion, are permitted provided that the following conditions are met:	5	* tion, are permitted provided that the following conditions are met:
6	*	6	*
7	* 1. Redistributions of source code must retain the above copyright notice,	7	* 1. Redistributions of source code must retain the above copyright notice,
8	* this list of conditions and the following disclaimer.	8	* this list of conditions and the following disclaimer.
9	*	9	*
10	* 2. Redistributions in binary form must reproduce the above copyright	10	* 2. Redistributions in binary form must reproduce the above copyright
11	* notice, this list of conditions and the following disclaimer in the	11	* notice, this list of conditions and the following disclaimer in the
12	* documentation and/or other materials provided with the distribution.	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	*	13	*
17	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED	14	* 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-	15	* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER-
19	* CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO	16	* CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
20	* EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE-	17	* EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE-
24	* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTH-	21	* 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	22	* ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
26	* OF THE POSSIBILITY OF SUCH DAMAGE.	23	* OF THE POSSIBILITY OF SUCH DAMAGE.
27	*	24	*
28	* Alternatively, the contents of this file may be used under the terms of	25	* 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	26	* the GNU General Public License ("GPL") version 2 or any later version,
30	* provisions of the GPL are applicable instead of the above. If you wish to	27	* in which case the provisions of the GPL are applicable instead of
31	* allow the use of your version of this file only under the terms of the	28	* the above. If you wish to allow the use of your version of this file
32	* GPL and not to allow others to use your version of this file under the	29	* only under the terms of the GPL and not to allow others to use your
33	* BSD license, indicate your decision by deleting the provisions above and	30	* version of this file under the BSD license, indicate your decision
34	* replace them with the notice and other provisions required by the GPL. If	31	* by deleting the provisions above and replace them with the notice
35	* you do not delete the provisions above, a recipient may use your version	32	* and other provisions required by the GPL. If you do not delete the
		33	* provisions above, a recipient may use your version of this file under
36	* of this file under either the BSD or the GPL.	34	* either the BSD or the GPL.
37	*/	35	*/
38		36
39	#include "lzfP.h"	37	#include "lzfP.h"
40		38
41	#define HSIZE (1 << (HLOG))	39	#define HSIZE (1 << (HLOG))
…		…
44	* don't play with this unless you benchmark!	42	* don't play with this unless you benchmark!
45	* decompression is not dependent on the hash function	43	* decompression is not dependent on the hash function
46	* the hashing function might seem strange, just believe me	44	* the hashing function might seem strange, just believe me
47	* it works ;)	45	* it works ;)
48	*/	46	*/
		47	#ifndef FRST
49	#define FRST(p) (((p[0]) << 8) \| p[1])	48	# define FRST(p) (((p[0]) << 8) \| p[1])
50	#define NEXT(v,p) (((v) << 8) \| p[2])	49	# define NEXT(v,p) (((v) << 8) \| p[2])
		50	# if ULTRA_FAST
		51	# define IDX(h) ((( h >> (3*8 - HLOG)) - h ) & (HSIZE - 1))
		52	# elif VERY_FAST
		53	# define IDX(h) ((( h >> (38 - HLOG)) - h5) & (HSIZE - 1))
		54	# else
51	#define IDX(h) ((((h ^ (h << 5)) >> (38 - HLOG)) - h5) & (HSIZE - 1))	55	# define IDX(h) ((((h ^ (h << 5)) >> (38 - HLOG)) - h5) & (HSIZE - 1))
		56	# endif
		57	#endif
52	/*	58	/*
53	* IDX works because it is very similar to a multiplicative hash, e.g.	59	* IDX works because it is very similar to a multiplicative hash, e.g.
54	* ((h * 57321 >> (3*8 - HLOG)) & (HSIZE - 1))	60	* ((h * 57321 >> (3*8 - HLOG)) & (HSIZE - 1))
55	* the latter is also quite fast on newer CPUs, and sligthly better	61	* the latter is also quite fast on newer CPUs, and compresses similarly.
56	*	62	*
57	* the next one is also quite good, albeit slow ;)	63	* the next one is also quite good, albeit slow ;)
58	* (int)(cos(h & 0xffffff) * 1e6)	64	* (int)(cos(h & 0xffffff) * 1e6)
59	*/	65	*/
60		66
…		…
65	# define IDX(h) ((h) & (HSIZE - 1))	71	# define IDX(h) ((h) & (HSIZE - 1))
66	#endif	72	#endif
67		73
68	#define MAX_LIT (1 << 5)	74	#define MAX_LIT (1 << 5)
69	#define MAX_OFF (1 << 13)	75	#define MAX_OFF (1 << 13)
70	#define MAX_REF ((1 << 8) + (1 << 3))	76	#define MAX_REF ((1 << 8) + (1 << 3))
		77
		78	#if __GNUC__ >= 3
		79	# define expect(expr,value) __builtin_expect ((expr),(value))
		80	# define inline inline
		81	#else
		82	# define expect(expr,value) (expr)
		83	# define inline static
		84	#endif
		85
		86	#define expect_false(expr) expect ((expr) != 0, 0)
		87	#define expect_true(expr) expect ((expr) != 0, 1)
71		88
72	/*	89	/*
73	* compressed format	90	* compressed format
74	*	91	*
75	* 000LLLLL <L+1> ; literal	92	* 000LLLLL <L+1> ; literal
76	* LLLOOOOO oooooooo ; backref L	93	* LLLooooo oooooooo ; backref L
77	* 111OOOOO LLLLLLLL oooooooo ; backref L+7	94	* 111ooooo LLLLLLLL oooooooo ; backref L+7
78	*	95	*
79	*/	96	*/
80		97
81	unsigned int	98	unsigned int
82	lzf_compress (const void *const in_data, unsigned int in_len,	99	lzf_compress (const void *const in_data, unsigned int in_len,
83	void *out_data, unsigned int out_len	100	void *out_data, unsigned int out_len
84	#if LZF_STATE_ARG	101	#if LZF_STATE_ARG
85	, LZF_STATE *htab	102	, LZF_STATE htab
86	#endif	103	#endif
87	)	104	)
88	{	105	{
89	#if !LZF_STATE_ARG	106	#if !LZF_STATE_ARG
90	LZF_STATE htab;	107	LZF_STATE htab;
…		…
94	u8 op = (u8 )out_data;	111	u8 op = (u8 )out_data;
95	const u8 *in_end = ip + in_len;	112	const u8 *in_end = ip + in_len;
96	u8 *out_end = op + out_len;	113	u8 *out_end = op + out_len;
97	const u8 *ref;	114	const u8 *ref;
98		115
99	unsigned int hval = FRST (ip);	116	unsigned int hval;
100	unsigned long off;	117	unsigned long off;
101	int lit = 0;	118	int lit;
		119
		120	if (!in_len \|\| !out_len)
		121	return 0;
102		122
103	#if INIT_HTAB	123	#if INIT_HTAB
104	# if USE_MEMCPY
105	memset (htab, 0, sizeof (htab));	124	memset (htab, 0, sizeof (htab));
106	# else	125	# if 0
107	for (hslot = htab; hslot < htab + HSIZE; hslot++)	126	for (hslot = htab; hslot < htab + HSIZE; hslot++)
108	*hslot++ = ip;	127	*hslot++ = ip;
109	# endif	128	# endif
110	#endif	129	#endif
111		130
112	for (;;)	131	lit = 0; op++; /* start run */
		132
		133	hval = FRST (ip);
		134	while (ip < in_end - 2)
113	{	135	{
114	if (ip < in_end - 2)	136	hval = NEXT (hval, ip);
		137	hslot = htab + IDX (hval);
		138	ref = hslot; hslot = ip;
		139
		140	if (1
		141	#if INIT_HTAB
		142	&& ref < ip /* the next test will actually take care of this, but this is faster */
		143	#endif
		144	&& (off = ip - ref - 1) < MAX_OFF
		145	&& ip + 4 < in_end
		146	&& ref > (u8 *)in_data
		147	#if STRICT_ALIGN
		148	&& ref[0] == ip[0]
		149	&& ref[1] == ip[1]
		150	&& ref[2] == ip[2]
		151	#else
		152	&& (u16 )ref == (u16 )ip
		153	&& ref[2] == ip[2]
		154	#endif
		155	)
115	{	156	{
116	hval = NEXT (hval, ip);
117	hslot = htab + IDX (hval);
118	ref = hslot; hslot = ip;
119
120	if (1
121	#if INIT_HTAB && !USE_MEMCPY
122	&& ref < ip /* the next test will actually take care of this, but this is faster */
123	#endif
124	&& (off = ip - ref - 1) < MAX_OFF
125	&& ip + 4 < in_end
126	&& ref > (u8 *)in_data
127	#if STRICT_ALIGN
128	&& ref[0] == ip[0]
129	&& ref[1] == ip[1]
130	&& ref[2] == ip[2]
131	#else
132	&& (u16 )ref == (u16 )ip
133	&& ref[2] == ip[2]
134	#endif
135	)
136	{
137	/* match found at ref++ /	157	/* match found at ref++ /
138	unsigned int len = 2;	158	unsigned int len = 2;
139	unsigned int maxlen = in_end - ip - len;	159	unsigned int maxlen = in_end - ip - len;
140	maxlen = maxlen > MAX_REF ? MAX_REF : maxlen;	160	maxlen = maxlen > MAX_REF ? MAX_REF : maxlen;
141		161
142	if (op + lit + 1 + 3 >= out_end)	162	if (maxlen > 8) maxlen = 8;//D
		163
		164	op [- lit - 1] = lit - 1; /* stop run */
		165	op -= !lit; /* undo run if length is zero */
		166
		167	if (expect_false (op + 3 + 1 >= out_end))
143	return 0;	168	return 0;
		169
		170	for (;;)
		171	{
		172	if (expect_true (maxlen > 16))
		173	{
		174	len++; if (ref [len] != ip [len]) break;
		175	len++; if (ref [len] != ip [len]) break;
		176	len++; if (ref [len] != ip [len]) break;
		177	len++; if (ref [len] != ip [len]) break;
		178
		179	len++; if (ref [len] != ip [len]) break;
		180	len++; if (ref [len] != ip [len]) break;
		181	len++; if (ref [len] != ip [len]) break;
		182	len++; if (ref [len] != ip [len]) break;
		183
		184	len++; if (ref [len] != ip [len]) break;
		185	len++; if (ref [len] != ip [len]) break;
		186	len++; if (ref [len] != ip [len]) break;
		187	len++; if (ref [len] != ip [len]) break;
		188
		189	len++; if (ref [len] != ip [len]) break;
		190	len++; if (ref [len] != ip [len]) break;
		191	len++; if (ref [len] != ip [len]) break;
		192	len++; if (ref [len] != ip [len]) break;
		193	}
144		194
145	do	195	do
146	len++;	196	len++;
147	while (len < maxlen && ref[len] == ip[len]);	197	while (len < maxlen && ref[len] == ip[len]);
148		198
149	if (lit)
150	{	199	break;
151	*op++ = lit - 1;
152	lit = -lit;
153	do
154	*op++ = ip[lit];
155	while (++lit);
156	}	200	}
157		201
158	len -= 2;	202	len -= 2;
159	ip++;	203	ip++;
160		204
161	if (len < 7)	205	if (len < 7)
162	{	206	{
163	*op++ = (off >> 8) + (len << 5);	207	*op++ = (off >> 8) + (len << 5);
164	}	208	}
165	else	209	else
166	{	210	{
167	*op++ = (off >> 8) + ( 7 << 5);	211	*op++ = (off >> 8) + ( 7 << 5);
168	*op++ = len - 7;	212	*op++ = len - 7;
169	}	213	}
170		214
171	*op++ = off;	215	*op++ = off;
172		216
173	#if ULTRA_FAST \|\| VERY_FAST	217	#if ULTRA_FAST \|\| VERY_FAST
174	ip += len;	218	ip += len;
175	#if VERY_FAST && !ULTRA_FAST	219	#if VERY_FAST && !ULTRA_FAST
176	--ip;	220	--ip;
177	#endif	221	#endif
178	hval = FRST (ip);	222	hval = FRST (ip);
179		223
		224	hval = NEXT (hval, ip);
		225	htab[IDX (hval)] = ip;
		226	ip++;
		227
		228	#if VERY_FAST && !ULTRA_FAST
		229	hval = NEXT (hval, ip);
		230	htab[IDX (hval)] = ip;
		231	ip++;
		232	#endif
		233	#else
		234	do
		235	{
180	hval = NEXT (hval, ip);	236	hval = NEXT (hval, ip);
181	htab[IDX (hval)] = ip;	237	htab[IDX (hval)] = ip;
182	ip++;	238	ip++;
183
184	#if VERY_FAST && !ULTRA_FAST
185	hval = NEXT (hval, ip);
186	htab[IDX (hval)] = ip;
187	ip++;
188	#endif
189	#else
190	do
191	{
192	hval = NEXT (hval, ip);
193	htab[IDX (hval)] = ip;
194	ip++;
195	}	239	}
196	while (len--);	240	while (len--);
197	#endif	241	#endif
198	continue;	242
199	}	243	lit = 0; op++; /* start run */
200	}	244	}
201	else if (ip == in_end)	245	else
202	break;
203
204	/* one more literal byte we must copy */
205	lit++;
206	ip++;
207
208	if (lit == MAX_LIT)
209	{	246	{
210	if (op + 1 + MAX_LIT >= out_end)	247	/* one more literal byte we must copy */
		248	if (expect_false (op >= out_end))
211	return 0;	249	return 0;
212		250
213	*op++ = MAX_LIT - 1;	251	lit++; op++ = ip++;
214	#if USE_MEMCPY	252
215	memcpy (op, ip - MAX_LIT, MAX_LIT);	253	if (expect_false (lit == MAX_LIT))
216	op += MAX_LIT;
217	lit = 0;
218	#else
219	lit = -lit;
220	do	254	{
221	*op++ = ip[lit];	255	op [- lit - 1] = lit - 1; /* stop run */
222	while (++lit);	256	lit = 0; op++; /* start run */
223	#endif	257	}
224	}	258	}
225	}	259	}
226		260
227	if (lit)	261	if (op + 3 > out_end) /* at most 3 bytes can be missing here */
		262	return 0;
		263
		264	while (ip < in_end)
228	{	265	{
229	if (op + lit + 1 >= out_end)	266	lit++; op++ = ip++;
230	return 0;
231		267
232	*op++ = lit - 1;	268	if (expect_false (lit == MAX_LIT))
233	lit = -lit;	269	{
234	do	270	op [- lit - 1] = lit - 1; /* stop run */
235	*op++ = ip[lit];	271	lit = 0; op++; /* start run */
236	while (++lit);	272	}
237	}	273	}
238		274
		275	op [- lit - 1] = lit - 1; /* end run */
		276	op -= !lit; /* undo run if length is zero */
		277
239	return op - (u8 *) out_data;	278	return op - (u8 *)out_data;
240	}	279	}
		280

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Comparing liblzf/lzf_c.c (file contents): Revision 1.9 by root, Tue Mar 8 19:59:52 2005 UTC vs. Revision 1.29 by root, Fri Nov 30 10:35:02 2007 UTC

Diff Legend

Comparing liblzf/lzf_c.c (file contents):
Revision 1.9 by root, Tue Mar 8 19:59:52 2005 UTC vs.
Revision 1.29 by root, Fri Nov 30 10:35:02 2007 UTC