Allow 'gzip -d' and 'bzip2 -d' without gunzip or bunzip2

Idea copied from the "ip" applet.

Signed-off-by: Kang-Che Sung <explorer09@gmail.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 14 insertions, 2 deletions

diff --git a/archival/bzip2.c b/archival/bzip2.c
index 47fa29af3..7e38e78b3 100644
--- a/archival/bzip2.c
+++ b/archival/bzip2.c
@@ -19,6 +19,15 @@
 //config:
 //config:         Unless you have a specific application which requires bzip2, you
 //config:         should probably say N here.
+//config:
+//config:config FEATURE_BZIP2_DECOMPRESS
+//config:       bool "Enable decompression"
+//config:       default y
+//config:       depends on BZIP2 || BUNZIP2 || BZCAT
+//config:       help
+//config:         Enable -d (--decompress) and -t (--test) options for bzip2.
+//config:         This will be automatically selected if bunzip2 or bzcat is
+//config:         enabled.
 
 //applet:IF_BZIP2(APPLET(bzip2, BB_DIR_USR_BIN, BB_SUID_DROP))
 //kbuild:lib-$(CONFIG_BZIP2) += bzip2.o
@@ -28,7 +37,10 @@
 //usage:#define bzip2_full_usage "\n\n"
 //usage:       "Compress FILEs (or stdin) with bzip2 algorithm\n"
 //usage:     "\n        -1..9   Compression level"
+//usage:        IF_FEATURE_BZIP2_DECOMPRESS(
 //usage:     "\n        -d      Decompress"
+//usage:     "\n        -t      Test file integrity"
+//usage:        )
 //usage:     "\n        -c      Write to stdout"
 //usage:     "\n        -f      Force"
 
@@ -184,8 +196,8 @@ int bzip2_main(int argc UNUSED_PARAM, char **argv)
 
         opt_complementary = "s2"; /* -s means -2 (compatibility) */
         /* Must match bbunzip's constants OPT_STDOUT, OPT_FORCE! */
-        opt = getopt32(argv, "cfv" IF_BUNZIP2("dt") "123456789qzs");
-#if ENABLE_BUNZIP2 /* bunzip2_main may not be visible... */
+        opt = getopt32(argv, "cfv" IF_FEATURE_BZIP2_DECOMPRESS("dt") "123456789qzs");
+#if ENABLE_FEATURE_BZIP2_DECOMPRESS /* bunzip2_main may not be visible... */
         if (opt & 0x18) // -d and/or -t
                 return bunzip2_main(argc, argv);
         opt >>= 5;