1 files changed, 78 insertions, 0 deletions
diff --git a/src/test/test-clock.c b/src/test/test-clock.c
new file mode 100644
index 0000000..714935c
--- /dev/null
+++ b/src/test/test-clock.c
@@ -0,0 +1,78 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/***
+  Copyright © 2016 Canonical Ltd.
+***/
+
+#include <unistd.h>
+#include <fcntl.h>
+
+#include "clock-util.h"
+#include "fd-util.h"
+#include "fileio.h"
+#include "fs-util.h"
+#include "log.h"
+#include "macro.h"
+#include "tmpfile-util.h"
+
+static void test_clock_is_localtime(void) {
+        _cleanup_(unlink_tempfilep) char adjtime[] = "/tmp/test-adjtime.XXXXXX";
+        _cleanup_fclose_ FILE* f = NULL;
+
+        static const struct scenario {
+                const char* contents;
+                int expected_result;
+        } scenarios[] = {
+                /* adjtime configures UTC */
+                {"0.0 0 0\n0\nUTC\n", 0},
+                /* adjtime configures local time */
+                {"0.0 0 0\n0\nLOCAL\n", 1},
+                /* no final EOL */
+                {"0.0 0 0\n0\nUTC", 0},
+                {"0.0 0 0\n0\nLOCAL", 1},
+                /* empty value -> defaults to UTC */
+                {"0.0 0 0\n0\n", 0},
+                /* unknown value -> defaults to UTC */
+                {"0.0 0 0\n0\nFOO\n", 0},
+                /* no third line */
+                {"0.0 0 0", 0},
+                {"0.0 0 0\n", 0},
+                {"0.0 0 0\n0", 0},
+        };
+
+        /* without an adjtime file we default to UTC */
+        assert_se(clock_is_localtime("/nonexisting/adjtime") == 0);
+
+        assert_se(fmkostemp_safe(adjtime, "w", &f) == 0);
+        log_info("adjtime test file: %s", adjtime);
+
+        for (size_t i = 0; i < ELEMENTSOF(scenarios); ++i) {
+                log_info("scenario #%zu:, expected result %i", i, scenarios[i].expected_result);
+                log_info("%s", scenarios[i].contents);
+                rewind(f);
+                assert_se(ftruncate(fileno(f), 0) == 0);
+                assert_se(write_string_stream(f, scenarios[i].contents, WRITE_STRING_FILE_AVOID_NEWLINE) == 0);
+                assert_se(clock_is_localtime(adjtime) == scenarios[i].expected_result);
+        }
+}
+
+/* Test with the real /etc/adjtime */
+static void test_clock_is_localtime_system(void) {
+        int r;
+        r = clock_is_localtime(NULL);
+
+        if (access("/etc/adjtime", R_OK) == 0) {
+                log_info("/etc/adjtime is readable, clock_is_localtime() == %i", r);
+                /* if /etc/adjtime exists we expect some answer, no error or
+                 * crash */
+                assert_se(IN_SET(r, 0, 1));
+        } else
+                /* default is UTC if there is no /etc/adjtime */
+                assert_se(r == 0 || ERRNO_IS_PRIVILEGE(r));
+}
+
+int main(int argc, char *argv[]) {
+        test_clock_is_localtime();
+        test_clock_is_localtime_system();
+
+        return 0;
+}