[ovs-dev] [PATCH] ovn-nbctl: Detect unrecognized short options in server mode.

[Jakub Sitnicki]

Because getopt() will set optopt for both known and unknown options,
we need to differentiate between them ourselves by checking if we
know the option. Do that by looking up its value.

Also, because we are using GNU extensions to getopt(), we need to be
resetting getopt() state by setting optind to 0 instead of 1 as
pointed out in NOTES in getopt(3) man-page. Not doing so results in
invalid reads and optopt being set to a garbarge value.

Fixes: 3ec06ea9c668 ("ovn-nbctl: Initial support for daemon mode.")
Signed-off-by: Jakub Sitnicki <jkbs at redhat.com>
---
 ovn/utilities/ovn-nbctl.c | 19 +++++++++++++++++--
 1 file changed, 17 insertions(+), 2 deletions(-)

diff --git a/ovn/utilities/ovn-nbctl.c b/ovn/utilities/ovn-nbctl.c
index 8b888294e..a1717d153 100644
--- a/ovn/utilities/ovn-nbctl.c
+++ b/ovn/utilities/ovn-nbctl.c
@@ -4844,6 +4844,19 @@ nbctl_cmd_init(void)
     ctl_register_commands(nbctl_commands);
 }
 
+static const struct option *
+find_option_by_value(const struct option *options, int value)
+{
+    const struct option *o;
+
+    for (o = options; o->name; o++) {
+        if (o->val == value) {
+            return o;
+        }
+    }
+    return NULL;
+}
+
 static char * OVS_WARN_UNUSED_RESULT
 server_parse_options(int argc, char *argv[], struct shash *local_options,
                      int *n_options_p)
@@ -4863,7 +4876,7 @@ server_parse_options(int argc, char *argv[], struct shash *local_options,
     short_options = build_short_options(global_long_options, false);
     options = append_command_options(global_long_options, OPT_LOCAL);
 
-    optind = 1;
+    optind = 0;
     opterr = 0;
     for (;;) {
         int idx;
@@ -4899,9 +4912,11 @@ server_parse_options(int argc, char *argv[], struct shash *local_options,
         TABLE_OPTION_HANDLERS(&table_style)
 
         case '?':
-            if (optopt) {
+            if (find_option_by_value(options, optopt)) {
                 error = xasprintf("option '%s' doesn't allow an argument",
                                   argv[optind-1]);
+            } else if (optopt) {
+                error = xasprintf("unrecognized option '%c'", optopt);
             } else {
                 error = xasprintf("unrecognized option '%s'", argv[optind-1]);
             }
-- 
2.14.4