cli: add nmc_complete_strv() which takes a string array for completion that may contain NULL

This will allow for a convenient calling pattern when some elements
should be printed optionally.

(cherry picked from commit 62b939de4e2288d0a9d305706db4cf47c34122d5)

2 files changed, 28 insertions, 10 deletions

diff --git a/clients/cli/common.c b/clients/cli/common.c
index 50dd0eb5cb..3c1c315d5e 100644
--- a/clients/cli/common.c
+++ b/clients/cli/common.c
@@ -1349,23 +1349,39 @@ nmc_do_cmd (NmCli *nmc, const NMCCommand cmds[], const char *cmd, int argc, char
 /**
  * nmc_complete_strings:
  * @prefix: a string to match
- * @...: a %NULL-terminated list of candidate strings
+ * @nargs: the number of elements in @args. Or -1 if @args is a NULL terminated
+ *   strv array.
+ * @args: the argument list. If @nargs is not -1, then some elements may
+ *   be %NULL to indicate to silently skip the values.
  *
  * Prints all the matching candidates for completion. Useful when there's
  * no better way to suggest completion other than a hardcoded string list.
  */
 void
-nmc_complete_strings (const char *prefix, ...)
+nmc_complete_strv (const char *prefix, gssize nargs, const char *const*args)
 {
-	va_list args;
-	const char *candidate;
+	gsize i, n;
+
+	if (prefix && !prefix[0])
+		prefix = NULL;
+
+	if (nargs < 0) {
+		nm_assert (nargs == -1);
+		n = NM_PTRARRAY_LEN (args);
+	} else
+		n = (gsize) nargs;
+
+	for (i = 0; i < n; i++) {
+		const char *candidate = args[i];
 
-	va_start (args, prefix);
-	while ((candidate = va_arg (args, const char *))) {
-		if (!*prefix || matches (prefix, candidate))
-			g_print ("%s\n", candidate);
+		if (!candidate)
+			continue;
+		if (   prefix
+		    && !matches (prefix, candidate))
+			continue;
+
+		g_print ("%s\n", candidate);
 	}
-	va_end (args);
 }
 
 /**
diff --git a/clients/cli/common.h b/clients/cli/common.h
index 71734acc98..688f2819f6 100644
--- a/clients/cli/common.h
+++ b/clients/cli/common.h
@@ -88,7 +88,9 @@ typedef struct {
 
 void nmc_do_cmd (NmCli *nmc, const NMCCommand cmds[], const char *cmd, int argc, char **argv);
 
-void nmc_complete_strings (const char *prefix, ...) G_GNUC_NULL_TERMINATED;
+void nmc_complete_strv (const char *prefix, gssize nargs, const char *const*args);
+
+#define nmc_complete_strings(prefix, ...) nmc_complete_strv ((prefix), NM_NARG (__VA_ARGS__), (const char *const[]) { __VA_ARGS__ })
 
 void nmc_complete_bool (const char *prefix);