1 files changed, 113 insertions, 4 deletions

diff --git a/archival/tar.c b/archival/tar.c
index 3129781d2..2909eca1b 100644
--- a/archival/tar.c
+++ b/archival/tar.c
@@ -22,7 +22,6 @@
  *
  * Licensed under GPLv2 or later, see file LICENSE in this source tree.
  */
-
 /* TODO: security with -C DESTDIR option can be enhanced.
  * Consider tar file created via:
  * $ tar cvf bug.tar anything.txt
@@ -42,6 +41,109 @@
  * This doesn't feel right, and IIRC GNU tar doesn't do that.
  */
 
+//config:config TAR
+//config:       bool "tar"
+//config:       default y
+//config:       help
+//config:         tar is an archiving program. It's commonly used with gzip to
+//config:         create compressed archives. It's probably the most widely used
+//config:         UNIX archive program.
+//config:
+//config:config FEATURE_TAR_CREATE
+//config:       bool "Enable archive creation"
+//config:       default y
+//config:       depends on TAR
+//config:       help
+//config:         If you enable this option you'll be able to create
+//config:         tar archives using the `-c' option.
+//config:
+//config:config FEATURE_TAR_AUTODETECT
+//config:       bool "Autodetect compressed tarballs"
+//config:       default y
+//config:       depends on TAR && (FEATURE_SEAMLESS_Z || FEATURE_SEAMLESS_GZ || FEATURE_SEAMLESS_BZ2 || FEATURE_SEAMLESS_LZMA || FEATURE_SEAMLESS_XZ)
+//config:       help
+//config:         With this option tar can automatically detect compressed
+//config:         tarballs. Currently it works only on files (not pipes etc).
+//config:
+//config:config FEATURE_TAR_FROM
+//config:       bool "Enable -X (exclude from) and -T (include from) options)"
+//config:       default y
+//config:       depends on TAR
+//config:       help
+//config:         If you enable this option you'll be able to specify
+//config:         a list of files to include or exclude from an archive.
+//config:
+//config:config FEATURE_TAR_OLDGNU_COMPATIBILITY
+//config:       bool "Support for old tar header format"
+//config:       default y
+//config:       depends on TAR || DPKG
+//config:       help
+//config:         This option is required to unpack archives created in
+//config:         the old GNU format; help to kill this old format by
+//config:         repacking your ancient archives with the new format.
+//config:
+//config:config FEATURE_TAR_OLDSUN_COMPATIBILITY
+//config:       bool "Enable untarring of tarballs with checksums produced by buggy Sun tar"
+//config:       default y
+//config:       depends on TAR || DPKG
+//config:       help
+//config:         This option is required to unpack archives created by some old
+//config:         version of Sun's tar (it was calculating checksum using signed
+//config:         arithmetic). It is said to be fixed in newer Sun tar, but "old"
+//config:         tarballs still exist.
+//config:
+//config:config FEATURE_TAR_GNU_EXTENSIONS
+//config:       bool "Support for GNU tar extensions (long filenames)"
+//config:       default y
+//config:       depends on TAR || DPKG
+//config:       help
+//config:         With this option busybox supports GNU long filenames and
+//config:         linknames.
+//config:
+//config:config FEATURE_TAR_LONG_OPTIONS
+//config:       bool "Enable long options"
+//config:       default y
+//config:       depends on TAR && LONG_OPTS
+//config:       help
+//config:         Enable use of long options, increases size by about 400 Bytes
+//config:
+//config:config FEATURE_TAR_TO_COMMAND
+//config:       bool "Support for writing to an external program"
+//config:       default y
+//config:       depends on TAR && FEATURE_TAR_LONG_OPTIONS
+//config:       help
+//config:         If you enable this option you'll be able to instruct tar to send
+//config:         the contents of each extracted file to the standard input of an
+//config:         external program.
+//config:
+//config:config FEATURE_TAR_UNAME_GNAME
+//config:       bool "Enable use of user and group names"
+//config:       default y
+//config:       depends on TAR
+//config:       help
+//config:         Enables use of user and group names in tar. This affects contents
+//config:         listings (-t) and preserving permissions when unpacking (-p).
+//config:         +200 bytes.
+//config:
+//config:config FEATURE_TAR_NOPRESERVE_TIME
+//config:       bool "Enable -m (do not preserve time) option"
+//config:       default y
+//config:       depends on TAR
+//config:       help
+//config:         With this option busybox supports GNU tar -m
+//config:         (do not preserve time) option.
+//config:
+//config:config FEATURE_TAR_SELINUX
+//config:       bool "Support for extracting SELinux labels"
+//config:       default n
+//config:       depends on TAR && SELINUX
+//config:       help
+//config:         With this option busybox supports restoring SELinux labels
+//config:         when extracting files from tar archives.
+
+//applet:IF_TAR(APPLET(tar, BB_DIR_BIN, BB_SUID_DROP))
+//kbuild:lib-$(CONFIG_TAR) += tar.o
+
 #include <fnmatch.h>
 #include "libbb.h"
 #include "bb_archive.h"
@@ -1096,8 +1198,14 @@ int tar_main(int argc UNUSED_PARAM, char **argv)
                 /*tar_handle->offset = 0; - already is */
         }
 
+        /* Zero processed headers (== empty file) is not a valid tarball.
+         * We (ab)use bb_got_signal as exitcode here,
+         * because check_errors_in_children() uses _it_ as error indicator.
+         */
+        bb_got_signal = EXIT_FAILURE;
+
         while (get_header_tar(tar_handle) == EXIT_SUCCESS)
-                continue;
+                bb_got_signal = EXIT_SUCCESS; /* saw at least one header, good */
 
         /* Check that every file that should have been extracted was */
         while (tar_handle->accept) {
@@ -1113,8 +1221,9 @@ int tar_main(int argc UNUSED_PARAM, char **argv)
                 close(tar_handle->src_fd);
 
         if (SEAMLESS_COMPRESSION || OPT_COMPRESS) {
+                /* Set bb_got_signal to 1 if a child died with !0 exitcode */
                 check_errors_in_children(0);
-                return bb_got_signal;
         }
-        return EXIT_SUCCESS;
+
+        return bb_got_signal;
 }