Add test to ensure that time advances both normally and in a daemon.

[sliver-openvswitch.git] / tests / test-timeval.c

diff --git a/tests/test-timeval.c b/tests/test-timeval.c
new file mode 100644 (file)
index 0000000..ba8b3d3
--- /dev/null
+++ b/tests/test-timeval.c
@@ -0,0 +1,118 @@
+/*
+ * Copyright (c) 2009 Nicira Networks.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <config.h>
+
+#include "timeval.h"
+
+#include <errno.h>
+#include <stdio.h>
+#include <sys/time.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include "daemon.h"
+#include "util.h"
+
+#undef NDEBUG
+#include <assert.h>
+
+static long long int
+gettimeofday_in_msec(void)
+{
+    struct timeval tv;
+
+    assert(!gettimeofday(&tv, NULL));
+    return timeval_to_msec(&tv);
+}
+
+static void
+do_test(void)
+{
+    /* Wait until we are awakened by a signal (typically EINTR due to the
+     * setitimer()).  Then ensure that, if time has really advanced by
+     * TIME_UPDATE_INTERVAL, then time_msec() reports that it advanced.
+     */
+    long long int start_time_msec;
+    long long int start_gtod;
+
+    start_time_msec = time_msec();
+    start_gtod = gettimeofday_in_msec();
+    for (;;) {
+        /* Wait up to 1 second.  Using select() to do the timeout avoids
+         * interfering with the interval timer. */
+        struct timeval timeout;
+        timeout.tv_sec = 1;
+        timeout.tv_usec = 0;
+        assert(select(0, NULL, NULL, NULL, &timeout) == -1 && errno == EINTR);
+
+        if (gettimeofday_in_msec() - start_gtod >= TIME_UPDATE_INTERVAL) {
+            assert(time_msec() - start_time_msec >= TIME_UPDATE_INTERVAL);
+            break;
+        }
+    }
+}
+
+static void
+usage(void)
+{
+    ovs_fatal(0, "usage: %s TEST, where TEST is \"plain\" or \"daemon\"",
+              program_name);
+}
+
+int
+main(int argc, char *argv[])
+{
+    set_program_name(argv[0]);
+    time_init();
+
+    if (argc != 2) {
+        usage();
+    } else if (!strcmp(argv[1], "plain")) {
+        do_test();
+    } else if (!strcmp(argv[1], "daemon")) {
+        /* Test that time still advances even in a daemon.  This is an
+         * interesting test because fork() cancels the interval timer. */
+        char cwd[1024];
+        FILE *success;
+
+        assert(getcwd(cwd, sizeof cwd) == cwd);
+
+        unlink("test-timeval.success");
+
+        /* Daemonize, with a pidfile in the current directory. */
+        set_detach();
+        set_pidfile(xasprintf("%s/test-timeval.pid", cwd));
+        set_no_chdir();
+        daemonize();
+
+        /* Run the test. */
+        do_test();
+
+        /* Report success by writing out a file, since the ultimate invoker of
+         * test-timeval can't wait on the daemonized process. */
+        success = fopen("test-timeval.success", "w");
+        if (!success) {
+            ovs_fatal(errno, "test-timeval.success: create failed");
+        }
+        fprintf(success, "success\n");
+        fclose(success);
+    } else {
+        usage();
+    }
+
+    return 0;
+}