flock: fix -c; improve error handling of fork+exec

function                                             old     new   delta
flock_main                                           254     334     +80

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

diff --git a/util-linux/flock.c b/util-linux/flock.c
index 05a747f724b678a0bc6cfeca032f4f42ad4b2783..539a835b7dcfab2421497b438ef5b32929b71fbf 100644 (file)
--- a/util-linux/flock.c
+++ b/util-linux/flock.c
@@ -57,7 +57,6 @@ int flock_main(int argc UNUSED_PARAM, char **argv)
        /* If it is "flock FILE -c PROG", then -c isn't caught by getopt32:
         * we use "+" in order to support "flock -opt FILE PROG -with-opts",
         * we need to remove -c by hand.
-        * TODO: in upstream, -c 'PROG ARGS' means "run sh -c 'PROG ARGS'"
         */
        if (argv[0]
         && argv[0][0] == '-'
@@ -66,6 +65,9 @@ int flock_main(int argc UNUSED_PARAM, char **argv)
            )
        ) {
                argv++;
+               if (argv[1])
+                       bb_error_msg_and_die("-c takes only one argument");
+               opt |= OPT_c;
        }
 
        if (OPT_s == LOCK_SH && OPT_x == LOCK_EX && OPT_n == LOCK_NB && OPT_u == LOCK_UN) {
@@ -90,8 +92,21 @@ int flock_main(int argc UNUSED_PARAM, char **argv)
                bb_perror_nomsg_and_die();
        }
 
-       if (argv[0])
+       if (argv[0]) {
+               if (!(opt & OPT_c)) {
+                       int rc = spawn_and_wait(argv);
+                       if (rc < 0)
+                               bb_simple_perror_msg(argv[0]);
+                       return rc;
+               }
+               /* -c 'PROG ARGS' means "run sh -c 'PROG ARGS'" */
+               argv -= 2;
+               argv[0] = (char*)get_shell_name();
+               argv[1] = (char*)"-c";
+               /* argv[2] = "PROG ARGS"; */
+               /* argv[3] = NULL; */
                return spawn_and_wait(argv);
+       }
 
        return EXIT_SUCCESS;
 }