diff options
author | David S. Miller <davem@davemloft.net> | 2010-01-23 03:31:06 -0500 |
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committer | David S. Miller <davem@davemloft.net> | 2010-01-23 03:31:06 -0500 |
commit | 51c24aaacaea90c8e87f1dec75a2ac7622b593f8 (patch) | |
tree | 9f54936c87764bef75e97395cb56b7d1e0df24c6 /lib/decompress_unlzo.c | |
parent | 4276e47e2d1c85a2477caf0d22b91c4f2377fba8 (diff) | |
parent | 6be325719b3e54624397e413efd4b33a997e55a3 (diff) |
Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Diffstat (limited to 'lib/decompress_unlzo.c')
-rw-r--r-- | lib/decompress_unlzo.c | 209 |
1 files changed, 209 insertions, 0 deletions
diff --git a/lib/decompress_unlzo.c b/lib/decompress_unlzo.c new file mode 100644 index 000000000000..db521f45626e --- /dev/null +++ b/lib/decompress_unlzo.c | |||
@@ -0,0 +1,209 @@ | |||
1 | /* | ||
2 | * LZO decompressor for the Linux kernel. Code borrowed from the lzo | ||
3 | * implementation by Markus Franz Xaver Johannes Oberhumer. | ||
4 | * | ||
5 | * Linux kernel adaptation: | ||
6 | * Copyright (C) 2009 | ||
7 | * Albin Tonnerre, Free Electrons <albin.tonnerre@free-electrons.com> | ||
8 | * | ||
9 | * Original code: | ||
10 | * Copyright (C) 1996-2005 Markus Franz Xaver Johannes Oberhumer | ||
11 | * All Rights Reserved. | ||
12 | * | ||
13 | * lzop and the LZO library are free software; you can redistribute them | ||
14 | * and/or modify them under the terms of the GNU General Public License as | ||
15 | * published by the Free Software Foundation; either version 2 of | ||
16 | * the License, or (at your option) any later version. | ||
17 | * | ||
18 | * This program is distributed in the hope that it will be useful, | ||
19 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
20 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | ||
21 | * GNU General Public License for more details. | ||
22 | * | ||
23 | * You should have received a copy of the GNU General Public License | ||
24 | * along with this program; see the file COPYING. | ||
25 | * If not, write to the Free Software Foundation, Inc., | ||
26 | * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. | ||
27 | * | ||
28 | * Markus F.X.J. Oberhumer | ||
29 | * <markus@oberhumer.com> | ||
30 | * http://www.oberhumer.com/opensource/lzop/ | ||
31 | */ | ||
32 | |||
33 | #ifdef STATIC | ||
34 | #include "lzo/lzo1x_decompress.c" | ||
35 | #else | ||
36 | #include <linux/slab.h> | ||
37 | #include <linux/decompress/unlzo.h> | ||
38 | #endif | ||
39 | |||
40 | #include <linux/types.h> | ||
41 | #include <linux/lzo.h> | ||
42 | #include <linux/decompress/mm.h> | ||
43 | |||
44 | #include <linux/compiler.h> | ||
45 | #include <asm/unaligned.h> | ||
46 | |||
47 | static const unsigned char lzop_magic[] = { | ||
48 | 0x89, 0x4c, 0x5a, 0x4f, 0x00, 0x0d, 0x0a, 0x1a, 0x0a }; | ||
49 | |||
50 | #define LZO_BLOCK_SIZE (256*1024l) | ||
51 | #define HEADER_HAS_FILTER 0x00000800L | ||
52 | |||
53 | STATIC inline int INIT parse_header(u8 *input, u8 *skip) | ||
54 | { | ||
55 | int l; | ||
56 | u8 *parse = input; | ||
57 | u8 level = 0; | ||
58 | u16 version; | ||
59 | |||
60 | /* read magic: 9 first bits */ | ||
61 | for (l = 0; l < 9; l++) { | ||
62 | if (*parse++ != lzop_magic[l]) | ||
63 | return 0; | ||
64 | } | ||
65 | /* get version (2bytes), skip library version (2), | ||
66 | * 'need to be extracted' version (2) and | ||
67 | * method (1) */ | ||
68 | version = get_unaligned_be16(parse); | ||
69 | parse += 7; | ||
70 | if (version >= 0x0940) | ||
71 | level = *parse++; | ||
72 | if (get_unaligned_be32(parse) & HEADER_HAS_FILTER) | ||
73 | parse += 8; /* flags + filter info */ | ||
74 | else | ||
75 | parse += 4; /* flags */ | ||
76 | |||
77 | /* skip mode and mtime_low */ | ||
78 | parse += 8; | ||
79 | if (version >= 0x0940) | ||
80 | parse += 4; /* skip mtime_high */ | ||
81 | |||
82 | l = *parse++; | ||
83 | /* don't care about the file name, and skip checksum */ | ||
84 | parse += l + 4; | ||
85 | |||
86 | *skip = parse - input; | ||
87 | return 1; | ||
88 | } | ||
89 | |||
90 | STATIC inline int INIT unlzo(u8 *input, int in_len, | ||
91 | int (*fill) (void *, unsigned int), | ||
92 | int (*flush) (void *, unsigned int), | ||
93 | u8 *output, int *posp, | ||
94 | void (*error_fn) (char *x)) | ||
95 | { | ||
96 | u8 skip = 0, r = 0; | ||
97 | u32 src_len, dst_len; | ||
98 | size_t tmp; | ||
99 | u8 *in_buf, *in_buf_save, *out_buf; | ||
100 | int obytes_processed = 0; | ||
101 | |||
102 | set_error_fn(error_fn); | ||
103 | |||
104 | if (output) { | ||
105 | out_buf = output; | ||
106 | } else if (!flush) { | ||
107 | error("NULL output pointer and no flush function provided"); | ||
108 | goto exit; | ||
109 | } else { | ||
110 | out_buf = malloc(LZO_BLOCK_SIZE); | ||
111 | if (!out_buf) { | ||
112 | error("Could not allocate output buffer"); | ||
113 | goto exit; | ||
114 | } | ||
115 | } | ||
116 | |||
117 | if (input && fill) { | ||
118 | error("Both input pointer and fill function provided, don't know what to do"); | ||
119 | goto exit_1; | ||
120 | } else if (input) { | ||
121 | in_buf = input; | ||
122 | } else if (!fill || !posp) { | ||
123 | error("NULL input pointer and missing position pointer or fill function"); | ||
124 | goto exit_1; | ||
125 | } else { | ||
126 | in_buf = malloc(lzo1x_worst_compress(LZO_BLOCK_SIZE)); | ||
127 | if (!in_buf) { | ||
128 | error("Could not allocate input buffer"); | ||
129 | goto exit_1; | ||
130 | } | ||
131 | } | ||
132 | in_buf_save = in_buf; | ||
133 | |||
134 | if (posp) | ||
135 | *posp = 0; | ||
136 | |||
137 | if (fill) | ||
138 | fill(in_buf, lzo1x_worst_compress(LZO_BLOCK_SIZE)); | ||
139 | |||
140 | if (!parse_header(input, &skip)) { | ||
141 | error("invalid header"); | ||
142 | goto exit_2; | ||
143 | } | ||
144 | in_buf += skip; | ||
145 | |||
146 | if (posp) | ||
147 | *posp = skip; | ||
148 | |||
149 | for (;;) { | ||
150 | /* read uncompressed block size */ | ||
151 | dst_len = get_unaligned_be32(in_buf); | ||
152 | in_buf += 4; | ||
153 | |||
154 | /* exit if last block */ | ||
155 | if (dst_len == 0) { | ||
156 | if (posp) | ||
157 | *posp += 4; | ||
158 | break; | ||
159 | } | ||
160 | |||
161 | if (dst_len > LZO_BLOCK_SIZE) { | ||
162 | error("dest len longer than block size"); | ||
163 | goto exit_2; | ||
164 | } | ||
165 | |||
166 | /* read compressed block size, and skip block checksum info */ | ||
167 | src_len = get_unaligned_be32(in_buf); | ||
168 | in_buf += 8; | ||
169 | |||
170 | if (src_len <= 0 || src_len > dst_len) { | ||
171 | error("file corrupted"); | ||
172 | goto exit_2; | ||
173 | } | ||
174 | |||
175 | /* decompress */ | ||
176 | tmp = dst_len; | ||
177 | r = lzo1x_decompress_safe((u8 *) in_buf, src_len, | ||
178 | out_buf, &tmp); | ||
179 | |||
180 | if (r != LZO_E_OK || dst_len != tmp) { | ||
181 | error("Compressed data violation"); | ||
182 | goto exit_2; | ||
183 | } | ||
184 | |||
185 | obytes_processed += dst_len; | ||
186 | if (flush) | ||
187 | flush(out_buf, dst_len); | ||
188 | if (output) | ||
189 | out_buf += dst_len; | ||
190 | if (posp) | ||
191 | *posp += src_len + 12; | ||
192 | if (fill) { | ||
193 | in_buf = in_buf_save; | ||
194 | fill(in_buf, lzo1x_worst_compress(LZO_BLOCK_SIZE)); | ||
195 | } else | ||
196 | in_buf += src_len; | ||
197 | } | ||
198 | |||
199 | exit_2: | ||
200 | if (!input) | ||
201 | free(in_buf); | ||
202 | exit_1: | ||
203 | if (!output) | ||
204 | free(out_buf); | ||
205 | exit: | ||
206 | return obytes_processed; | ||
207 | } | ||
208 | |||
209 | #define decompress unlzo | ||