Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git...
[linux-2.6/mini2440.git] / lib / decompress.c
blobd2842f57167446e0221352035a2276b87318ea4b
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>
13 #include <linux/types.h>
14 #include <linux/string.h>
16 #ifndef CONFIG_DECOMPRESS_GZIP
17 # define gunzip NULL
18 #endif
19 #ifndef CONFIG_DECOMPRESS_BZIP2
20 # define bunzip2 NULL
21 #endif
22 #ifndef CONFIG_DECOMPRESS_LZMA
23 # define unlzma NULL
24 #endif
26 static const struct compress_format {
27 unsigned char magic[2];
28 const char *name;
29 decompress_fn decompressor;
30 } compressed_formats[] = {
31 { {037, 0213}, "gzip", gunzip },
32 { {037, 0236}, "gzip", gunzip },
33 { {0x42, 0x5a}, "bzip2", bunzip2 },
34 { {0x5d, 0x00}, "lzma", unlzma },
35 { {0, 0}, NULL, NULL }
38 decompress_fn decompress_method(const unsigned char *inbuf, int len,
39 const char **name)
41 const struct compress_format *cf;
43 if (len < 2)
44 return NULL; /* Need at least this much... */
46 for (cf = compressed_formats; cf->name; cf++) {
47 if (!memcmp(inbuf, cf->magic, 2))
48 break;
51 if (name)
52 *name = cf->name;
53 return cf->decompressor;