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>

1 files changed, 17 insertions, 2 deletions

diff --git a/util-linux/flock.c b/util-linux/flock.c
index 05a747f72..539a835b7 100644
--- 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;
 }