add osmo_gettimeofday as a shim around gettimeofday

This allows feeding a custom time for unit tests by overriding
osmo_gettimeofday.

Change-Id: Ic7a81a6eb51f27fe452962b91f2eae2070d87089

1 files changed, 58 insertions, 0 deletions

diff --git a/src/timer_gettimeofday.c b/src/timer_gettimeofday.c
new file mode 100644
index 00000000..81a1598d
--- /dev/null
+++ b/src/timer_gettimeofday.c
@@ -0,0 +1,58 @@
+/*
+ * (C) 2016 by sysmocom s.f.m.c. GmbH <info@sysmocom.de>
+ * All Rights Reserved
+ *
+ * Authors: Neels Hofmeyr <nhofmeyr@sysmocom.de>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ */
+
+/*! \addtogroup timer
+ *  @{
+ */
+
+/*! \file timer_gettimeofday.c
+ */
+
+#include <stdbool.h>
+#include <sys/time.h>
+
+bool osmo_gettimeofday_override = false;
+struct timeval osmo_gettimeofday_override_time = { 23, 424242 };
+
+/*! \brief shim around gettimeofday to be able to set the time manually.
+ * To override, set osmo_gettimeofday_override == true and set the desired
+ * current time in osmo_gettimeofday_override_time. */
+int osmo_gettimeofday(struct timeval *tv, struct timezone *tz)
+{
+	if (osmo_gettimeofday_override) {
+		*tv = osmo_gettimeofday_override_time;
+		return 0;
+	}
+
+	return gettimeofday(tv, tz);
+}
+
+/*! \brief convenience function to advance the fake time.
+ * Add the given values to osmo_gettimeofday_override_time. */
+void osmo_gettimeofday_override_add(time_t secs, suseconds_t usecs)
+{
+	struct timeval val = { secs, usecs };
+	timeradd(&osmo_gettimeofday_override_time, &val,
+		 &osmo_gettimeofday_override_time);
+}
+
+/*! @} */