Line data Source code
1 : /*
2 : * Copyright (c) 2000-2010 Marc Alexander Lehmann <schmorp@schmorp.de>
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 : * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
15 : * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER-
16 : * CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
17 : * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE-
18 : * CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19 : * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
20 : * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
21 : * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTH-
22 : * ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
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.
35 : */
36 :
37 : #include "lzfP.h"
38 :
39 : #if AVOID_ERRNO
40 : # define SET_ERRNO(n)
41 : #else
42 : # include <errno.h>
43 : # define SET_ERRNO(n) errno = (n)
44 : #endif
45 :
46 : #if USE_REP_MOVSB /* small win on amd, big loss on intel */
47 : #if (__i386 || __amd64) && __GNUC__ >= 3
48 : # define lzf_movsb(dst, src, len) \
49 : asm ("rep movsb" \
50 : : "=D" (dst), "=S" (src), "=c" (len) \
51 : : "0" (dst), "1" (src), "2" (len));
52 : #endif
53 : #endif
54 :
55 : unsigned int
56 76 : lzf_decompress (const void *const in_data, unsigned int in_len,
57 : void *out_data, unsigned int out_len)
58 : {
59 76 : u8 const *ip = (const u8 *)in_data;
60 76 : u8 *op = (u8 *)out_data;
61 76 : u8 const *const in_end = ip + in_len;
62 76 : u8 *const out_end = op + out_len;
63 :
64 : do
65 : {
66 156884256 : unsigned int ctrl = *ip++;
67 :
68 156884256 : if (ctrl < (1 << 5)) /* literal run */
69 : {
70 37212842 : ctrl++;
71 :
72 37212842 : if (op + ctrl > out_end)
73 : {
74 0 : SET_ERRNO (E2BIG);
75 0 : return 0;
76 : }
77 :
78 : #if CHECK_INPUT
79 37212842 : if (ip + ctrl > in_end)
80 : {
81 0 : SET_ERRNO (EINVAL);
82 0 : return 0;
83 : }
84 : #endif
85 :
86 : #ifdef lzf_movsb
87 : lzf_movsb (op, ip, ctrl);
88 : #else
89 37212842 : switch (ctrl)
90 : {
91 6283680 : case 32: *op++ = *ip++; case 31: *op++ = *ip++; case 30: *op++ = *ip++; case 29: *op++ = *ip++;
92 6408420 : case 28: *op++ = *ip++; case 27: *op++ = *ip++; case 26: *op++ = *ip++; case 25: *op++ = *ip++;
93 6589826 : case 24: *op++ = *ip++; case 23: *op++ = *ip++; case 22: *op++ = *ip++; case 21: *op++ = *ip++;
94 6842352 : case 20: *op++ = *ip++; case 19: *op++ = *ip++; case 18: *op++ = *ip++; case 17: *op++ = *ip++;
95 7026232 : case 16: *op++ = *ip++; case 15: *op++ = *ip++; case 14: *op++ = *ip++; case 13: *op++ = *ip++;
96 7782684 : case 12: *op++ = *ip++; case 11: *op++ = *ip++; case 10: *op++ = *ip++; case 9: *op++ = *ip++;
97 9772988 : case 8: *op++ = *ip++; case 7: *op++ = *ip++; case 6: *op++ = *ip++; case 5: *op++ = *ip++;
98 11932072 : case 4: *op++ = *ip++; case 3: *op++ = *ip++; case 2: *op++ = *ip++; case 1: *op++ = *ip++;
99 : }
100 : #endif
101 : }
102 : else /* back reference */
103 : {
104 119671414 : unsigned int len = ctrl >> 5;
105 :
106 119671414 : u8 *ref = op - ((ctrl & 0x1f) << 8) - 1;
107 :
108 : #if CHECK_INPUT
109 119671414 : if (ip >= in_end)
110 : {
111 0 : SET_ERRNO (EINVAL);
112 0 : return 0;
113 : }
114 : #endif
115 119671414 : if (len == 7)
116 : {
117 9119768 : len += *ip++;
118 : #if CHECK_INPUT
119 9119768 : if (ip >= in_end)
120 : {
121 0 : SET_ERRNO (EINVAL);
122 0 : return 0;
123 : }
124 : #endif
125 : }
126 :
127 119671414 : ref -= *ip++;
128 :
129 119671414 : if (op + len + 2 > out_end)
130 : {
131 0 : SET_ERRNO (E2BIG);
132 0 : return 0;
133 : }
134 :
135 119671414 : if (ref < (u8 *)out_data)
136 : {
137 0 : SET_ERRNO (EINVAL);
138 0 : return 0;
139 : }
140 :
141 : #ifdef lzf_movsb
142 : len += 2;
143 : lzf_movsb (op, ref, len);
144 : #else
145 119671414 : switch (len)
146 : {
147 : default:
148 3507802 : len += 2;
149 :
150 3507802 : if (op >= ref + len)
151 : {
152 : /* disjunct areas */
153 3483054 : memcpy (op, ref, len);
154 3483054 : op += len;
155 : }
156 : else
157 : {
158 : /* overlapping, use octte by octte copying */
159 : do
160 868332 : *op++ = *ref++;
161 868332 : while (--len);
162 : }
163 :
164 3507802 : break;
165 :
166 1428032 : case 9: *op++ = *ref++;
167 3383952 : case 8: *op++ = *ref++;
168 5611966 : case 7: *op++ = *ref++;
169 9755026 : case 6: *op++ = *ref++;
170 15586340 : case 5: *op++ = *ref++;
171 22224342 : case 4: *op++ = *ref++;
172 38011370 : case 3: *op++ = *ref++;
173 69203586 : case 2: *op++ = *ref++;
174 116163612 : case 1: *op++ = *ref++;
175 116163612 : case 0: *op++ = *ref++; /* two octets more */
176 116163612 : *op++ = *ref++;
177 : }
178 : #endif
179 : }
180 : }
181 156884256 : while (ip < in_end);
182 :
183 76 : return op - (u8 *)out_data;
184 : }
185 :
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