Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/anholt...
[linux-2.6/linux-2.6-openrd.git] / lib / decompress.c
bloba7606815541f4631d675707950a11de0609aff89
1 /*
2 * decompress.c
4 * Detect the decompression method based on magic number
5 */
7 #include <linux/decompress/generic.h>
9 #include <linux/decompress/bunzip2.h>
10 #include <linux/decompress/unlzma.h>
11 #include <linux/decompress/inflate.h>
12 #include <linux/decompress/unlzo.h>
14 #include <linux/types.h>
15 #include <linux/string.h>
17 #ifndef CONFIG_DECOMPRESS_GZIP
18 # define gunzip NULL
19 #endif
20 #ifndef CONFIG_DECOMPRESS_BZIP2
21 # define bunzip2 NULL
22 #endif
23 #ifndef CONFIG_DECOMPRESS_LZMA
24 # define unlzma NULL
25 #endif
26 #ifndef CONFIG_DECOMPRESS_LZO
27 # define unlzo NULL
28 #endif
30 static const struct compress_format {
31 unsigned char magic[2];
32 const char *name;
33 decompress_fn decompressor;
34 } compressed_formats[] = {
35 { {037, 0213}, "gzip", gunzip },
36 { {037, 0236}, "gzip", gunzip },
37 { {0x42, 0x5a}, "bzip2", bunzip2 },
38 { {0x5d, 0x00}, "lzma", unlzma },
39 { {0x89, 0x4c}, "lzo", unlzo },
40 { {0, 0}, NULL, NULL }
43 decompress_fn decompress_method(const unsigned char *inbuf, int len,
44 const char **name)
46 const struct compress_format *cf;
48 if (len < 2)
49 return NULL; /* Need at least this much... */
51 for (cf = compressed_formats; cf->name; cf++) {
52 if (!memcmp(inbuf, cf->magic, 2))
53 break;
56 if (name)
57 *name = cf->name;
58 return cf->decompressor;