diff options
Diffstat (limited to 'archival/libarchive/open_transformer.c')
| -rw-r--r-- | archival/libarchive/open_transformer.c | 140 |
1 files changed, 140 insertions, 0 deletions
diff --git a/archival/libarchive/open_transformer.c b/archival/libarchive/open_transformer.c index aa8c1021c..743ffee02 100644 --- a/archival/libarchive/open_transformer.c +++ b/archival/libarchive/open_transformer.c @@ -6,6 +6,16 @@ #include "libbb.h" #include "bb_archive.h" +#define ZIPPED (ENABLE_FEATURE_SEAMLESS_LZMA \ + || ENABLE_FEATURE_SEAMLESS_BZ2 \ + || ENABLE_FEATURE_SEAMLESS_GZ \ + /* || ENABLE_FEATURE_SEAMLESS_Z */ \ +) + +#if ZIPPED +# include "bb_archive.h" +#endif + /* transformer(), more than meets the eye */ /* * On MMU machine, the transform_prog is removed by macro magic @@ -52,3 +62,133 @@ void FAST_FUNC open_transformer(int fd, close(fd_pipe.wr); /* don't want to write to the child */ xmove_fd(fd_pipe.rd, fd); } + + +/* Used by e.g. rpm which gives us a fd without filename, + * thus we can't guess the format from filename's extension. + */ +#if ZIPPED +void FAST_FUNC setup_unzip_on_fd(int fd /*, int fail_if_not_detected*/) +{ + const int fail_if_not_detected = 1; + 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); + enum { xformer_prog = 0 }; +# else + enum { xformer = 0 }; + const char *xformer_prog; +# endif + + /* .gz and .bz2 both have 2-byte signature, and their + * unpack_XXX_stream wants this header skipped. */ + xread(fd, magic.b16, sizeof(magic.b16[0])); + if (ENABLE_FEATURE_SEAMLESS_GZ + && magic.b16[0] == GZIP_MAGIC + ) { +# if BB_MMU + xformer = unpack_gz_stream; +# else + xformer_prog = "gunzip"; +# endif + goto found_magic; + } + if (ENABLE_FEATURE_SEAMLESS_BZ2 + && magic.b16[0] == BZIP2_MAGIC + ) { +# if BB_MMU + xformer = unpack_bz2_stream; +# else + xformer_prog = "bunzip2"; +# endif + goto found_magic; + } + if (ENABLE_FEATURE_SEAMLESS_XZ + && magic.b16[0] == XZ_MAGIC1 + ) { + offset = -6; + xread(fd, magic.b32, sizeof(magic.b32[0])); + if (magic.b32[0] == XZ_MAGIC2) { +# if BB_MMU + xformer = unpack_xz_stream; + /* unpack_xz_stream wants fd at position 6, no need to seek */ + //xlseek(fd, offset, SEEK_CUR); +# else + xformer_prog = "unxz"; +# endif + goto found_magic; + } + } + + /* No known magic seen */ + if (fail_if_not_detected) + bb_error_msg_and_die("no gzip" + IF_FEATURE_SEAMLESS_BZ2("/bzip2") + IF_FEATURE_SEAMLESS_XZ("/xz") + " magic"); + xlseek(fd, offset, SEEK_CUR); + return; + + found_magic: +# if !BB_MMU + /* NOMMU version of open_transformer execs + * an external unzipper that wants + * file position at the start of the file */ + xlseek(fd, offset, SEEK_CUR); +# endif + open_transformer(fd, xformer, xformer_prog); +} +#endif /* ZIPPED */ + +int FAST_FUNC open_zipped(const char *fname) +{ +#if !ZIPPED + return open(fname, O_RDONLY); +#else + char *sfx; + int fd; + + fd = open(fname, O_RDONLY); + if (fd < 0) + return fd; + + sfx = strrchr(fname, '.'); + if (sfx) { + sfx++; + if (ENABLE_FEATURE_SEAMLESS_LZMA && strcmp(sfx, "lzma") == 0) + /* .lzma has no header/signature, just trust it */ + open_transformer(fd, unpack_lzma_stream, "unlzma"); + else + if ((ENABLE_FEATURE_SEAMLESS_GZ && strcmp(sfx, "gz") == 0) + || (ENABLE_FEATURE_SEAMLESS_BZ2 && strcmp(sfx, "bz2") == 0) + || (ENABLE_FEATURE_SEAMLESS_XZ && strcmp(sfx, "xz") == 0) + ) { + setup_unzip_on_fd(fd /*, fail_if_not_detected: 1*/); + } + } + + return fd; +#endif +} + +void* FAST_FUNC xmalloc_open_zipped_read_close(const char *fname, size_t *maxsz_p) +{ + int fd; + char *image; + + fd = open_zipped(fname); + if (fd < 0) + return NULL; + + image = xmalloc_read(fd, maxsz_p); + if (!image) + bb_perror_msg("read error from '%s'", fname); + close(fd); + + return image; +} |