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Comparing liblzf/lzf_d.c (file contents):
Revision 1.2 by root, Sun Nov 17 11:39:26 2002 UTC vs.
Revision 1.11 by root, Sun May 30 05:52:57 2010 UTC

1/* 1/*
2 * Copyright (c) 2000-2002 Marc Alexander Lehmann <pcg@goof.com> 2 * Copyright (c) 2000-2010 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,
… …
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 * 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 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-
21 * CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 18 * CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
22 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; 19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
23 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 20 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
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.
24 *
25 * Alternatively, the contents of this file may be used under the terms of
26 * the GNU General Public License ("GPL") version 2 or any later version,
27 * in which case the provisions of the GPL are applicable instead of
28 * the above. If you wish to allow the use of your version of this file
29 * only under the terms of the GPL and not to allow others to use your
30 * version of this file under the BSD license, indicate your decision
31 * by deleting the provisions above and replace them with the notice
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
34 * either the BSD or the GPL.
27 */ 35 */
28 36
29#include <errno.h> 37#include "lzfP.h"
30 38
31#include "lzfP.h" 39#include <string.h> /* for memcpy/memset */
40
41#if AVOID_ERRNO
42# define SET_ERRNO(n)
43#else
44# include <errno.h>
45# define SET_ERRNO(n) errno = (n)
46#endif
47
48#if USE_REP_MOVSB /* small win on amd, big loss on intel */
49#if (__i386 || __amd64) && __GNUC__ >= 3
50# define lzf_movsb(dst, src, len) \
51 asm ("rep movsb" \
52 : "=D" (dst), "=S" (src), "=c" (len) \
53 : "0" (dst), "1" (src), "2" (len));
54#endif
55#endif
32 56
33unsigned int 57unsigned int
34lzf_decompress (const void *const in_data, unsigned int in_len, 58lzf_decompress (const void *const in_data, unsigned int in_len,
35 void *out_data, unsigned int out_len) 59 void *out_data, unsigned int out_len)
36{ 60{
37 u8 const *ip = in_data; 61 u8 const *ip = (const u8 *)in_data;
38 u8 *op = out_data; 62 u8 *op = (u8 *)out_data;
39 u8 const *const in_end = ip + in_len; 63 u8 const *const in_end = ip + in_len;
40 u8 *const out_end = op + out_len; 64 u8 *const out_end = op + out_len;
41 65
42 do 66 do
43 { 67 {
… …
47 { 71 {
48 ctrl++; 72 ctrl++;
49 73
50 if (op + ctrl > out_end) 74 if (op + ctrl > out_end)
51 { 75 {
52 errno = E2BIG; 76 SET_ERRNO (E2BIG);
53 return 0; 77 return 0;
54 } 78 }
55 79
56#if USE_MEMCPY 80#if CHECK_INPUT
81 if (ip + ctrl > in_end)
82 {
83 SET_ERRNO (EINVAL);
84 return 0;
85 }
86#endif
87
88#ifdef lzf_movsb
57 memcpy (op, ip, ctrl); 89 lzf_movsb (op, ip, ctrl);
58 op += ctrl;
59 ip += ctrl;
60#else 90#else
91 switch (ctrl)
61 do 92 {
62 *op++ = *ip++; 93 case 32: *op++ = *ip++; case 31: *op++ = *ip++; case 30: *op++ = *ip++; case 29: *op++ = *ip++;
63 while (--ctrl); 94 case 28: *op++ = *ip++; case 27: *op++ = *ip++; case 26: *op++ = *ip++; case 25: *op++ = *ip++;
95 case 24: *op++ = *ip++; case 23: *op++ = *ip++; case 22: *op++ = *ip++; case 21: *op++ = *ip++;
96 case 20: *op++ = *ip++; case 19: *op++ = *ip++; case 18: *op++ = *ip++; case 17: *op++ = *ip++;
97 case 16: *op++ = *ip++; case 15: *op++ = *ip++; case 14: *op++ = *ip++; case 13: *op++ = *ip++;
98 case 12: *op++ = *ip++; case 11: *op++ = *ip++; case 10: *op++ = *ip++; case 9: *op++ = *ip++;
99 case 8: *op++ = *ip++; case 7: *op++ = *ip++; case 6: *op++ = *ip++; case 5: *op++ = *ip++;
100 case 4: *op++ = *ip++; case 3: *op++ = *ip++; case 2: *op++ = *ip++; case 1: *op++ = *ip++;
101 }
64#endif 102#endif
65 } 103 }
66 else /* back reference */ 104 else /* back reference */
67 { 105 {
68 unsigned int len = ctrl >> 5; 106 unsigned int len = ctrl >> 5;
69 107
70 u8 *ref = op - ((ctrl & 0x1f) << 8) - 1; 108 u8 *ref = op - ((ctrl & 0x1f) << 8) - 1;
71 109
110#if CHECK_INPUT
111 if (ip >= in_end)
112 {
113 SET_ERRNO (EINVAL);
114 return 0;
115 }
116#endif
72 if (len == 7) 117 if (len == 7)
118 {
73 len += *ip++; 119 len += *ip++;
120#if CHECK_INPUT
121 if (ip >= in_end)
122 {
123 SET_ERRNO (EINVAL);
124 return 0;
125 }
126#endif
74 127 }
128
75 ref -= *ip++; 129 ref -= *ip++;
76 130
77 if (op + len + 2 > out_end) 131 if (op + len + 2 > out_end)
78 { 132 {
79 errno = E2BIG; 133 SET_ERRNO (E2BIG);
80 return 0; 134 return 0;
81 } 135 }
82 136
83 if (ref < (u8 *)out_data) 137 if (ref < (u8 *)out_data)
84 { 138 {
85 errno = EINVAL; 139 SET_ERRNO (EINVAL);
86 return 0; 140 return 0;
87 } 141 }
88 142
89 *op++ = *ref++; 143#ifdef lzf_movsb
90 *op++ = *ref++; 144 len += 2;
145 lzf_movsb (op, ref, len);
146#else
147 switch (len)
148 {
149 default:
150 len += 2;
91 151
92 do 152 if (op >= ref + len)
153 {
154 /* disjunct areas */
155 memcpy (op, ref, len);
156 op += len;
157 }
158 else
159 {
160 /* overlapping, use octte by octte copying */
161 do
93 *op++ = *ref++; 162 *op++ = *ref++;
94 while (--len); 163 while (--len);
164 }
165
166 break;
167
168 case 9: *op++ = *ref++;
169 case 8: *op++ = *ref++;
170 case 7: *op++ = *ref++;
171 case 6: *op++ = *ref++;
172 case 5: *op++ = *ref++;
173 case 4: *op++ = *ref++;
174 case 3: *op++ = *ref++;
175 case 2: *op++ = *ref++;
176 case 1: *op++ = *ref++;
177 case 0: *op++ = *ref++; /* two octets more */
178 *op++ = *ref++;
179 }
180#endif
95 } 181 }
96 } 182 }
97 while (op < out_end && ip < in_end); 183 while (ip < in_end);
98 184
99 return op - (u8 *)out_data; 185 return op - (u8 *)out_data;
100} 186}
101 187

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