d0751937 |
1 | /* |
2 | * Copyright (c) 2000-2007 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 | /* |
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 | */ |
54 | |
55 | unsigned int |
56 | lzf_decompress (const void *const in_data, unsigned int in_len, |
57 | void *out_data, unsigned int out_len) |
58 | { |
59 | u8 const *ip = (const u8 *)in_data; |
60 | u8 *op = (u8 *)out_data; |
61 | u8 const *const in_end = ip + in_len; |
62 | u8 *const out_end = op + out_len; |
63 | |
64 | do |
65 | { |
66 | unsigned int ctrl = *ip++; |
67 | |
68 | if (ctrl < (1 << 5)) /* literal run */ |
69 | { |
70 | ctrl++; |
71 | |
72 | if (op + ctrl > out_end) |
73 | { |
74 | SET_ERRNO (E2BIG); |
75 | return 0; |
76 | } |
77 | |
78 | #if CHECK_INPUT |
79 | if (ip + ctrl > in_end) |
80 | { |
81 | SET_ERRNO (EINVAL); |
82 | return 0; |
83 | } |
84 | #endif |
85 | |
86 | #ifdef lzf_movsb |
87 | lzf_movsb (op, ip, ctrl); |
88 | #else |
89 | do |
90 | *op++ = *ip++; |
91 | while (--ctrl); |
92 | #endif |
93 | } |
94 | else /* back reference */ |
95 | { |
96 | unsigned int len = ctrl >> 5; |
97 | |
98 | u8 *ref = op - ((ctrl & 0x1f) << 8) - 1; |
99 | |
100 | #if CHECK_INPUT |
101 | if (ip >= in_end) |
102 | { |
103 | SET_ERRNO (EINVAL); |
104 | return 0; |
105 | } |
106 | #endif |
107 | if (len == 7) |
108 | { |
109 | len += *ip++; |
110 | #if CHECK_INPUT |
111 | if (ip >= in_end) |
112 | { |
113 | SET_ERRNO (EINVAL); |
114 | return 0; |
115 | } |
116 | #endif |
117 | } |
118 | |
119 | ref -= *ip++; |
120 | |
121 | if (op + len + 2 > out_end) |
122 | { |
123 | SET_ERRNO (E2BIG); |
124 | return 0; |
125 | } |
126 | |
127 | if (ref < (u8 *)out_data) |
128 | { |
129 | SET_ERRNO (EINVAL); |
130 | return 0; |
131 | } |
132 | |
133 | #ifdef lzf_movsb |
134 | len += 2; |
135 | lzf_movsb (op, ref, len); |
136 | #else |
137 | *op++ = *ref++; |
138 | *op++ = *ref++; |
139 | |
140 | do |
141 | *op++ = *ref++; |
142 | while (--len); |
143 | #endif |
144 | } |
145 | } |
146 | while (ip < in_end); |
147 | |
148 | return op - (u8 *)out_data; |
149 | } |
150 | |