1 | /* |
2 | * Copyright (c) 2000-2010 Marc Alexander Lehmann <[email protected]> |
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 | #if defined(__GNUC__) && __GNUC__ >= 7 |
56 | #pragma GCC diagnostic push |
57 | #pragma GCC diagnostic ignored "-Wimplicit-fallthrough" |
58 | #endif |
59 | size_t |
60 | lzf_decompress (const void *const in_data, size_t in_len, |
61 | void *out_data, size_t out_len) |
62 | { |
63 | u8 const *ip = (const u8 *)in_data; |
64 | u8 *op = (u8 *)out_data; |
65 | u8 const *const in_end = ip + in_len; |
66 | u8 *const out_end = op + out_len; |
67 | |
68 | while (ip < in_end) |
69 | { |
70 | unsigned int ctrl; |
71 | ctrl = *ip++; |
72 | |
73 | if (ctrl < (1 << 5)) /* literal run */ |
74 | { |
75 | ctrl++; |
76 | |
77 | if (op + ctrl > out_end) |
78 | { |
79 | SET_ERRNO (E2BIG); |
80 | return 0; |
81 | } |
82 | |
83 | #if CHECK_INPUT |
84 | if (ip + ctrl > in_end) |
85 | { |
86 | SET_ERRNO (EINVAL); |
87 | return 0; |
88 | } |
89 | #endif |
90 | |
91 | #ifdef lzf_movsb |
92 | lzf_movsb (op, ip, ctrl); |
93 | #else |
94 | switch (ctrl) |
95 | { |
96 | case 32: *op++ = *ip++; case 31: *op++ = *ip++; case 30: *op++ = *ip++; case 29: *op++ = *ip++; |
97 | case 28: *op++ = *ip++; case 27: *op++ = *ip++; case 26: *op++ = *ip++; case 25: *op++ = *ip++; |
98 | case 24: *op++ = *ip++; case 23: *op++ = *ip++; case 22: *op++ = *ip++; case 21: *op++ = *ip++; |
99 | case 20: *op++ = *ip++; case 19: *op++ = *ip++; case 18: *op++ = *ip++; case 17: *op++ = *ip++; |
100 | case 16: *op++ = *ip++; case 15: *op++ = *ip++; case 14: *op++ = *ip++; case 13: *op++ = *ip++; |
101 | case 12: *op++ = *ip++; case 11: *op++ = *ip++; case 10: *op++ = *ip++; case 9: *op++ = *ip++; |
102 | case 8: *op++ = *ip++; case 7: *op++ = *ip++; case 6: *op++ = *ip++; case 5: *op++ = *ip++; |
103 | case 4: *op++ = *ip++; case 3: *op++ = *ip++; case 2: *op++ = *ip++; case 1: *op++ = *ip++; |
104 | } |
105 | #endif |
106 | } |
107 | else /* back reference */ |
108 | { |
109 | unsigned int len = ctrl >> 5; |
110 | |
111 | u8 *ref = op - ((ctrl & 0x1f) << 8) - 1; |
112 | |
113 | #if CHECK_INPUT |
114 | if (ip >= in_end) |
115 | { |
116 | SET_ERRNO (EINVAL); |
117 | return 0; |
118 | } |
119 | #endif |
120 | if (len == 7) |
121 | { |
122 | len += *ip++; |
123 | #if CHECK_INPUT |
124 | if (ip >= in_end) |
125 | { |
126 | SET_ERRNO (EINVAL); |
127 | return 0; |
128 | } |
129 | #endif |
130 | } |
131 | |
132 | ref -= *ip++; |
133 | |
134 | if (op + len + 2 > out_end) |
135 | { |
136 | SET_ERRNO (E2BIG); |
137 | return 0; |
138 | } |
139 | |
140 | if (ref < (u8 *)out_data) |
141 | { |
142 | SET_ERRNO (EINVAL); |
143 | return 0; |
144 | } |
145 | |
146 | #ifdef lzf_movsb |
147 | len += 2; |
148 | lzf_movsb (op, ref, len); |
149 | #else |
150 | switch (len) |
151 | { |
152 | default: |
153 | len += 2; |
154 | |
155 | if (op >= ref + len) |
156 | { |
157 | /* disjunct areas */ |
158 | memcpy (op, ref, len); |
159 | op += len; |
160 | } |
161 | else |
162 | { |
163 | /* overlapping, use octte by octte copying */ |
164 | do |
165 | *op++ = *ref++; |
166 | while (--len); |
167 | } |
168 | |
169 | break; |
170 | |
171 | case 9: *op++ = *ref++; /* fall-thru */ |
172 | case 8: *op++ = *ref++; /* fall-thru */ |
173 | case 7: *op++ = *ref++; /* fall-thru */ |
174 | case 6: *op++ = *ref++; /* fall-thru */ |
175 | case 5: *op++ = *ref++; /* fall-thru */ |
176 | case 4: *op++ = *ref++; /* fall-thru */ |
177 | case 3: *op++ = *ref++; /* fall-thru */ |
178 | case 2: *op++ = *ref++; /* fall-thru */ |
179 | case 1: *op++ = *ref++; /* fall-thru */ |
180 | case 0: *op++ = *ref++; /* two octets more */ |
181 | *op++ = *ref++; /* fall-thru */ |
182 | } |
183 | #endif |
184 | } |
185 | } |
186 | |
187 | return op - (u8 *)out_data; |
188 | } |
189 | #if defined(__GNUC__) && __GNUC__ >= 5 |
190 | #pragma GCC diagnostic pop |
191 | #endif |
192 | |