core: add nm_utils_uuid_generate_from_strings()

Add function to create variant3 UUIDs based on a set
of concatenated strings.

src/NetworkManagerUtils.c

@@ -1739,6 +1739,48 @@ nm_utils_ascii_str_to_int64 (const char *str, guint base, gint64 min, gint64 max
 	return v;
 }
 
+/**
+ * nm_utils_uuid_generate_from_strings:
+ * @string1: a variadic list of strings. Must be NULL terminated.
+ *
+ * Returns a variant3 UUID based on the concatenated C strings.
+ * It does not simply concatenate them, but also includes the
+ * terminating '\0' character. For example "a", "b", gives
+ * "a\0b\0\0".
+ *
+ * This has the advantage, that the following invocations
+ * all give different UUIDs: (""), ("",""), ("","a"), ("a",""),
+ * ("aa"), ("aa", ""), ("", "aa"), ...
+ */
+char *
+nm_utils_uuid_generate_from_strings (const char *string1, ...)
+{
+	GString *str;
+	va_list args;
+	const char *s;
+	char *uuid;
+
+	if (!string1)
+		return nm_utils_uuid_generate_from_string (NULL, 0, NM_UTILS_UUID_TYPE_VARIANT3, NM_UTILS_UUID_NS);
+
+	str = g_string_sized_new (120); /* effectively allocates power of 2 (128)*/
+
+	g_string_append_len (str, string1, strlen (string1) + 1);
+
+	va_start (args, string1);
+	s = va_arg (args, const char *);
+	while (s) {
+		g_string_append_len (str, s, strlen (s) + 1);
+		s = va_arg (args, const char *);
+	}
+
+	uuid = nm_utils_uuid_generate_from_string (str->str, str->len, NM_UTILS_UUID_TYPE_VARIANT3, NM_UTILS_UUID_NS);
+
+	g_string_free (str, TRUE);
+	return uuid;
+}
+
+/**************************************************************************/
 
 static gint64 monotonic_timestamp_offset_sec;