Basic unit tests for update_current_time().

This function is about to get more complicated, so we should track
how it's working.

1 files changed, 102 insertions, 0 deletions

diff --git a/src/test/test_mainloop.c b/src/test/test_mainloop.c
new file mode 100644
index 0000000000..2f8a7bca67
--- /dev/null
+++ b/src/test/test_mainloop.c
@@ -0,0 +1,102 @@
+/* Copyright (c) 2018, The Tor Project, Inc. */
+/* See LICENSE for licensing information */
+
+/**
+ * \file test_mainloop.c
+ * \brief Tests for functions closely related to the Tor main loop
+ */
+
+#include "test.h"
+#include "log_test_helpers.h"
+
+#include "or.h"
+#include "main.h"
+
+static void
+test_mainloop_update_time_normal(void *arg)
+{
+  (void)arg;
+
+  /* This time is in the past as of when this test was written. */
+  time_t now = 1525272090;
+  reset_uptime();
+  update_current_time(now);
+  tt_int_op(approx_time(), OP_EQ, now);
+  tt_int_op(get_uptime(), OP_EQ, 0);
+
+  update_current_time(now); // Same time as before is a no-op.
+  tt_int_op(get_uptime(), OP_EQ, 0);
+
+  now += 1;
+  update_current_time(now);
+  tt_int_op(approx_time(), OP_EQ, now);
+  tt_int_op(get_uptime(), OP_EQ, 1);
+
+  now += 2; // two-second jump is unremarkable.
+  update_current_time(now);
+  tt_int_op(approx_time(), OP_EQ, now);
+  tt_int_op(get_uptime(), OP_EQ, 3);
+
+  now -= 1; // a one-second hop backwards is also unremarkable.
+  update_current_time(now);
+  tt_int_op(approx_time(), OP_EQ, now); // it changes the approx time...
+  tt_int_op(get_uptime(), OP_EQ, 3); // but it doesn't roll back our uptime
+
+ done:
+  ;
+}
+
+static void
+test_mainloop_update_time_jumps(void *arg)
+{
+  (void)arg;
+
+  /* This time is in the past as of when this test was written. */
+  time_t now = 220897152;
+  reset_uptime();
+  update_current_time(now);
+  tt_int_op(approx_time(), OP_EQ, now);
+  tt_int_op(get_uptime(), OP_EQ, 0);
+
+  /* Put some uptime on the clock.. */
+  now += 3;
+  update_current_time(now);
+  tt_int_op(approx_time(), OP_EQ, now);
+  tt_int_op(get_uptime(), OP_EQ, 3);
+
+  /* Now try jumping forward. */
+  setup_capture_of_logs(LOG_NOTICE);
+  now += 3600;
+  update_current_time(now);
+  expect_single_log_msg_containing(
+               "Your system clock just jumped 3600 seconds forward");
+  tt_int_op(approx_time(), OP_EQ, now);
+  tt_int_op(get_uptime(), OP_EQ, 3); // no uptime change.
+  mock_clean_saved_logs();
+
+  now -= 600;
+  update_current_time(now);
+  expect_single_log_msg_containing(
+               "Your system clock just jumped 600 seconds backward");
+  tt_int_op(approx_time(), OP_EQ, now);
+  tt_int_op(get_uptime(), OP_EQ, 3); // no uptime change.
+
+  /* uptime tracking should go normally now if the clock moves sensibly. */
+  now += 2;
+  update_current_time(now);
+  tt_int_op(approx_time(), OP_EQ, now);
+  tt_int_op(get_uptime(), OP_EQ, 5);
+
+ done:
+  teardown_capture_of_logs();
+}
+
+#define MAINLOOP_TEST(name) \
+  { #name, test_mainloop_## name , TT_FORK, NULL, NULL }
+
+struct testcase_t mainloop_tests[] = {
+  MAINLOOP_TEST(update_time_normal),
+  MAINLOOP_TEST(update_time_jumps),
+  END_OF_TESTCASES
+};
+