diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/Makefile | 9 | ||||
| -rw-r--r-- | lib/decompress.c | 50 |
2 files changed, 55 insertions, 4 deletions
diff --git a/lib/Makefile b/lib/Makefile index d9ac5a4..790de7c 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -11,7 +11,8 @@ lib-y := ctype.o string.o vsprintf.o cmdline.o \ rbtree.o radix-tree.o dump_stack.o \ idr.o int_sqrt.o extable.o prio_tree.o \ sha1.o irq_regs.o reciprocal_div.o argv_split.o \ - proportions.o prio_heap.o ratelimit.o show_mem.o is_single_threaded.o + proportions.o prio_heap.o ratelimit.o show_mem.o \ + is_single_threaded.o decompress.o lib-$(CONFIG_MMU) += ioremap.o lib-$(CONFIG_SMP) += cpumask.o @@ -65,9 +66,9 @@ obj-$(CONFIG_REED_SOLOMON) += reed_solomon/ obj-$(CONFIG_LZO_COMPRESS) += lzo/ obj-$(CONFIG_LZO_DECOMPRESS) += lzo/ -obj-$(CONFIG_DECOMPRESS_GZIP) += decompress_inflate.o -obj-$(CONFIG_DECOMPRESS_BZIP2) += decompress_bunzip2.o -obj-$(CONFIG_DECOMPRESS_LZMA) += decompress_unlzma.o +lib-$(CONFIG_DECOMPRESS_GZIP) += decompress_inflate.o +lib-$(CONFIG_DECOMPRESS_BZIP2) += decompress_bunzip2.o +lib-$(CONFIG_DECOMPRESS_LZMA) += decompress_unlzma.o obj-$(CONFIG_TEXTSEARCH) += textsearch.o obj-$(CONFIG_TEXTSEARCH_KMP) += ts_kmp.o diff --git a/lib/decompress.c b/lib/decompress.c new file mode 100644 index 0000000..edac55c --- /dev/null +++ b/lib/decompress.c @@ -0,0 +1,50 @@ +/* + * decompress.c + * + * Detect the decompression method based on magic number + */ + +#include <linux/decompress/generic.h> + +#include <linux/decompress/bunzip2.h> +#include <linux/decompress/unlzma.h> +#include <linux/decompress/inflate.h> + +#include <linux/types.h> +#include <linux/string.h> + +static const struct compress_format { + unsigned char magic[2]; + const char *name; + decompress_fn decompressor; +} compressed_formats[] = { +#ifdef CONFIG_DECOMPRESS_GZIP + { {037, 0213}, "gzip", gunzip }, + { {037, 0236}, "gzip", gunzip }, +#endif +#ifdef CONFIG_DECOMPRESS_BZIP2 + { {0x42, 0x5a}, "bzip2", bunzip2 }, +#endif +#ifdef CONFIG_DECOMPRESS_LZMA + { {0x5d, 0x00}, "lzma", unlzma }, +#endif + { {0, 0}, NULL, NULL } +}; + +decompress_fn decompress_method(const unsigned char *inbuf, int len, + const char **name) +{ + const struct compress_format *cf; + + if (len < 2) + return NULL; /* Need at least this much... */ + + for (cf = compressed_formats; cf->decompressor; cf++) { + if (!memcmp(inbuf, cf->magic, 2)) + break; + + } + if (name) + *name = cf->name; + return cf->decompressor; +} |
