networkctl: return error or warning when interfaces are not matched

We'd just print nothing and exit with 0. If the user gave an explicit
name, we should fail. If a pattern didn't match, we should at least warn.

$ networkctl status enx54ee75cb1dc0a* --no-pager && echo $?
No interfaces matched.
0

$ networkctl status enx54ee75cb1dc0a --no-pager
Interface "enx54ee75cb1dc0a" not found.
1

src/basic/strv.c

@@ -800,12 +800,13 @@ char **strv_shell_escape(char **l, const char *bad) {
         return l;
 }
 
-bool strv_fnmatch(char* const* patterns, const char *s, int flags) {
-        char* const* p;
-
-        STRV_FOREACH(p, patterns)
-                if (fnmatch(*p, s, flags) == 0)
+bool strv_fnmatch_full(char* const* patterns, const char *s, int flags, size_t *matched_pos) {
+        for (size_t i = 0; patterns && patterns[i]; i++)
+                if (fnmatch(patterns[i], s, flags) == 0) {
+                        if (matched_pos)
+                                *matched_pos = i;
                         return true;
+                }
 
         return false;
 }

src/basic/strv.h

@@ -177,7 +177,10 @@ void strv_print(char * const *l);
 char **strv_reverse(char **l);
 char **strv_shell_escape(char **l, const char *bad);
 
-bool strv_fnmatch(char* const* patterns, const char *s, int flags);
+bool strv_fnmatch_full(char* const* patterns, const char *s, int flags, size_t *matched_pos);
+static inline bool strv_fnmatch(char* const* patterns, const char *s, int flags) {
+        return strv_fnmatch_full(patterns, s, flags, NULL);
+}
 
 static inline bool strv_fnmatch_or_empty(char* const* patterns, const char *s, int flags) {
         assert(s);