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;
 

src/NetworkManagerUtils.h

@@ -160,6 +160,10 @@ void nm_utils_log_connection_diff (NMConnection *connection, NMConnection *diff_
 
 gint64 nm_utils_ascii_str_to_int64 (const char *str, guint base, gint64 min, gint64 max, gint64 fallback);
 
+#define NM_UTILS_UUID_NS "b425e9fb-7598-44b4-9e3b-5a2e3aaa4905"
+
+char *nm_utils_uuid_generate_from_strings (const char *string1, ...) G_GNUC_NULL_TERMINATED;
+
 #define NM_UTILS_NS_PER_SECOND  ((gint64) 1000000000)
 gint64 nm_utils_get_monotonic_timestamp_ns (void);
 gint64 nm_utils_get_monotonic_timestamp_us (void);

src/tests/test-general.c

@@ -729,6 +729,53 @@ test_connection_sort_autoconnect_priority (void)
 
 /*******************************************/
 
+static void
+__test_uuid (const char *expected_uuid, const char *str, gssize slen, char *uuid_test)
+{
+	g_assert (uuid_test);
+	g_assert (nm_utils_is_uuid (uuid_test));
+
+	if (strcmp (uuid_test, expected_uuid)) {
+		g_error ("UUID test failed (1): text=%s, len=%lld, expected=%s, uuid_test=%s",
+		         str, (long long) slen, expected_uuid, uuid_test);
+	}
+	g_free (uuid_test);
+
+	uuid_test = nm_utils_uuid_generate_from_string (str, slen, NM_UTILS_UUID_TYPE_VARIANT3, NM_UTILS_UUID_NS);
+
+	g_assert (uuid_test);
+	g_assert (nm_utils_is_uuid (uuid_test));
+
+	if (strcmp (uuid_test, expected_uuid)) {
+		g_error ("UUID test failed (2): text=%s; len=%lld, expected=%s, uuid2=%s",
+		         str, (long long) slen, expected_uuid, uuid_test);
+	}
+	g_free (uuid_test);
+}
+
+#define _test_uuid(expected_uuid, str, strlen, ...) __test_uuid (expected_uuid, str, strlen, nm_utils_uuid_generate_from_strings(__VA_ARGS__, NULL))
+
+static void
+test_nm_utils_uuid_generate_from_strings (void)
+{
+	_test_uuid ("b07c334a-399b-32de-8d50-58e4e08f98e3", "",         0, NULL);
+	_test_uuid ("b8a426cb-bcb5-30a3-bd8f-6786fea72df9", "\0",       1, "");
+	_test_uuid ("12a4a982-7aae-39e1-951e-41aeb1250959", "a\0",      2, "a");
+	_test_uuid ("69e22c7e-f89f-3a43-b239-1cb52ed8db69", "aa\0",     3, "aa");
+	_test_uuid ("59829fd3-5ad5-3d90-a7b0-4911747e4088", "\0\0",     2, "",   "");
+	_test_uuid ("01ad0e06-6c50-3384-8d86-ddab81421425", "a\0\0",    3, "a",  "");
+	_test_uuid ("e1ed8647-9ed3-3ec8-8c6d-e8204524d71d", "aa\0\0",   4, "aa", "");
+	_test_uuid ("fb1c7cd6-275c-3489-9382-83b900da8af0", "\0a\0",    3, "",   "a");
+	_test_uuid ("5d79494e-c4ba-31a6-80a2-d6016ccd7e17", "a\0a\0",   4, "a",  "a");
+	_test_uuid ("fd698d86-1b60-3ebe-855f-7aada9950a8d", "aa\0a\0",  5, "aa", "a");
+	_test_uuid ("8c573b48-0f01-30ba-bb94-c5f59f4fe517", "\0aa\0",   4, "",   "aa");
+	_test_uuid ("2bdd3d46-eb83-3c53-a41b-a724d04b5544", "a\0aa\0",  5, "a",  "aa");
+	_test_uuid ("13d4b780-07c1-3ba7-b449-81c4844ef039", "aa\0aa\0", 6, "aa", "aa");
+	_test_uuid ("dd265bf7-c05a-3037-9939-b9629858a477", "a\0b\0",   4, "a",  "b");
+}
+
+/*******************************************/
+
 NMTST_DEFINE ();
 
 int
@@ -751,6 +798,8 @@ main (int argc, char **argv)
 
 	g_test_add_func ("/general/connection-sort/autoconnect-priority", test_connection_sort_autoconnect_priority);
 
+	g_test_add_func ("/general/nm_utils_uuid_generate_from_strings", test_nm_utils_uuid_generate_from_strings);
+
 	return g_test_run ();
 }