From 8e96efa32314ec5a4e6ace9a6fe7a1694e2e7d90 Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Thu, 28 Feb 2013 18:06:09 +0100 Subject: [PATCH] zcat: if seamless uncompressors are defined, autodetect file's format function old new delta bbunpack 526 622 +96 packed_usage 29335 29341 +6 gunzip_main 64 67 +3 Signed-off-by: Denys Vlasenko --- archival/bbunzip.c | 54 ++++++++++++++++++++++++++++++++++------------ 1 file changed, 40 insertions(+), 14 deletions(-) diff --git a/archival/bbunzip.c b/archival/bbunzip.c index 46f99cf78..54dc2f5f1 100644 --- a/archival/bbunzip.c +++ b/archival/bbunzip.c @@ -14,6 +14,7 @@ enum { OPT_VERBOSE = 1 << 2, OPT_DECOMPRESS = 1 << 3, OPT_TEST = 1 << 4, + SEAMLESS_MAGIC = (1 << 31) * SEAMLESS_COMPRESSION, }; static @@ -39,7 +40,7 @@ int FAST_FUNC bbunpack(char **argv, ) { struct stat stat_buf; - IF_DESKTOP(long long) int status; + IF_DESKTOP(long long) int status = 0; char *filename, *new_name; smallint exitcode = 0; transformer_aux_data_t aux; @@ -54,14 +55,23 @@ int FAST_FUNC bbunpack(char **argv, /* Open src */ if (filename) { - if (stat(filename, &stat_buf) != 0) { - bb_simple_perror_msg(filename); + if (!(option_mask32 & SEAMLESS_MAGIC)) { + if (stat(filename, &stat_buf) != 0) { + err_name: + bb_simple_perror_msg(filename); err: - exitcode = 1; - goto free_name; + exitcode = 1; + goto free_name; + } + if (open_to_or_warn(STDIN_FILENO, filename, O_RDONLY, 0)) + goto err; + } else { + /* "clever zcat" */ + int fd = open_zipped(filename); + if (fd < 0) + goto err_name; + xmove_fd(fd, STDIN_FILENO); } - if (open_to_or_warn(STDIN_FILENO, filename, O_RDONLY, 0)) - goto err; } /* Special cases: test, stdout */ @@ -98,11 +108,23 @@ int FAST_FUNC bbunpack(char **argv, "use -f to force it"); } - init_transformer_aux_data(&aux); - aux.check_signature = 1; - status = unpacker(&aux); - if (status < 0) - exitcode = 1; + if (!(option_mask32 & SEAMLESS_MAGIC)) { + init_transformer_aux_data(&aux); + aux.check_signature = 1; + status = unpacker(&aux); + if (status < 0) + exitcode = 1; + } else { + /* "clever zcat" */ + if (!filename) { + if (setup_unzip_on_fd(STDIN_FILENO, /*fail_if_not_detected*/ 0)) + goto err; + } + if (bb_copyfd_eof(STDIN_FILENO, STDOUT_FILENO) < 0) { + /* Disk full, tty closed, etc. No point in continuing */ + xfunc_die(); + } + } if (!(option_mask32 & OPT_STDOUT)) xclose(STDOUT_FILENO); /* with error check! */ @@ -294,9 +316,13 @@ int gunzip_main(int argc UNUSED_PARAM, char **argv) { getopt32(argv, "cfvdtn"); argv += optind; - /* if called as zcat */ + + /* If called as zcat... + * Normally, "zcat" is just "gunzip -c". + * But if seamless magic is enabled, then we are much more clever. + */ if (applet_name[1] == 'c') - option_mask32 |= OPT_STDOUT; + option_mask32 |= OPT_STDOUT | SEAMLESS_MAGIC; return bbunpack(argv, unpack_gunzip, make_new_name_gunzip, /*unused:*/ NULL); } -- 2.25.1