Commit | Line | Data |
---|---|---|
889c92d2 PA |
1 | /* |
2 | * decompress.c | |
3 | * | |
4 | * Detect the decompression method based on magic number | |
5 | */ | |
6 | ||
7 | #include <linux/decompress/generic.h> | |
8 | ||
9 | #include <linux/decompress/bunzip2.h> | |
10 | #include <linux/decompress/unlzma.h> | |
11 | #include <linux/decompress/inflate.h> | |
12 | ||
13 | #include <linux/types.h> | |
14 | #include <linux/string.h> | |
15 | ||
16 | static const struct compress_format { | |
17 | unsigned char magic[2]; | |
18 | const char *name; | |
19 | decompress_fn decompressor; | |
20 | } compressed_formats[] = { | |
21 | #ifdef CONFIG_DECOMPRESS_GZIP | |
22 | { {037, 0213}, "gzip", gunzip }, | |
23 | { {037, 0236}, "gzip", gunzip }, | |
24 | #endif | |
25 | #ifdef CONFIG_DECOMPRESS_BZIP2 | |
26 | { {0x42, 0x5a}, "bzip2", bunzip2 }, | |
27 | #endif | |
28 | #ifdef CONFIG_DECOMPRESS_LZMA | |
29 | { {0x5d, 0x00}, "lzma", unlzma }, | |
30 | #endif | |
31 | { {0, 0}, NULL, NULL } | |
32 | }; | |
33 | ||
34 | decompress_fn decompress_method(const unsigned char *inbuf, int len, | |
35 | const char **name) | |
36 | { | |
37 | const struct compress_format *cf; | |
38 | ||
39 | if (len < 2) | |
40 | return NULL; /* Need at least this much... */ | |
41 | ||
42 | for (cf = compressed_formats; cf->decompressor; cf++) { | |
43 | if (!memcmp(inbuf, cf->magic, 2)) | |
44 | break; | |
45 | ||
46 | } | |
47 | if (name) | |
48 | *name = cf->name; | |
49 | return cf->decompressor; | |
50 | } |