diff options
Diffstat (limited to 'libbb/read.c')
| -rw-r--r-- | libbb/read.c | 21 |
1 files changed, 13 insertions, 8 deletions
diff --git a/libbb/read.c b/libbb/read.c index cd6bbeb..b1eb3f2 100644 --- a/libbb/read.c +++ b/libbb/read.c @@ -312,7 +312,11 @@ void* FAST_FUNC xmalloc_xopen_read_close(const char *filename, size_t *maxsz_p) void FAST_FUNC setup_unzip_on_fd(int fd /*, int fail_if_not_detected*/) { const int fail_if_not_detected = 1; - unsigned char magic[8]; + union { + uint8_t b[4]; + uint16_t b16[2]; + uint32_t b32[1]; + } magic; int offset = -2; # if BB_MMU IF_DESKTOP(long long) int FAST_FUNC (*xformer)(int src_fd, int dst_fd); @@ -324,9 +328,9 @@ void FAST_FUNC setup_unzip_on_fd(int fd /*, int fail_if_not_detected*/) /* .gz and .bz2 both have 2-byte signature, and their * unpack_XXX_stream wants this header skipped. */ - xread(fd, magic, 2); + xread(fd, magic.b16, sizeof(magic.b16)); if (ENABLE_FEATURE_SEAMLESS_GZ - && magic[0] == 0x1f && magic[1] == 0x8b + && magic.b16[0] == GZIP_MAGIC ) { # if BB_MMU xformer = unpack_gz_stream; @@ -336,7 +340,7 @@ void FAST_FUNC setup_unzip_on_fd(int fd /*, int fail_if_not_detected*/) goto found_magic; } if (ENABLE_FEATURE_SEAMLESS_BZ2 - && magic[0] == 'B' && magic[1] == 'Z' + && magic.b16[0] == BZIP2_MAGIC ) { # if BB_MMU xformer = unpack_bz2_stream; @@ -346,19 +350,20 @@ void FAST_FUNC setup_unzip_on_fd(int fd /*, int fail_if_not_detected*/) goto found_magic; } if (ENABLE_FEATURE_SEAMLESS_XZ - && magic[0] == 0xfd && magic[1] == '7' + && magic.b16[0] == XZ_MAGIC1 ) { /* .xz signature: 0xfd, '7', 'z', 'X', 'Z', 0x00 */ /* More info at: http://tukaani.org/xz/xz-file-format.txt */ offset = -6; - xread(fd, magic + 2, 4); - if (strcmp((char*)magic + 2, "zXZ") == 0) { + xread(fd, magic.b32, sizeof(magic.b32)); + if (magic.b32[0] == XZ_MAGIC2) { # if BB_MMU xformer = unpack_xz_stream; + /* unpack_xz_stream wants fd at position 0 */ + xlseek(fd, offset, SEEK_CUR); # else xformer_prog = "unxz"; # endif - xlseek(fd, offset, SEEK_CUR); goto found_magic; } } |