swapon: more robust progname probing

Currently, the 'swapoff' is the default behavior. It means that if you
have a libtool wrapper script in your build directory the executed binary
name is 'lt-swapon' and then "swapon -a" is interpreted as "swapoff -a".

Any random argv[0] should not be interpreted as "swapoff".

Signed-off-by: Karel Zak <kzak@redhat.com>

diff --git a/mount/swapon.c b/mount/swapon.c
index d89c6a965800f30d3846e9546fb5ee672d69b488..a66d59d6d6cd97420a6c72729123b13ee9b72c1b 100644 (file)
--- a/mount/swapon.c
+++ b/mount/swapon.c
@@ -791,6 +791,9 @@ main(int argc, char *argv[]) {
 
        if (streq(progname, "swapon"))
                return main_swapon(argc, argv);
-       else
+       else if (streq(progname, "swapoff"))
                return main_swapoff(argc, argv);
+
+       errx(EXIT_FAILURE, _("'%s' is unsupported program name "
+                       "(must be 'swapon' or 'swapoff')."), progname);
 }