| /* |
| * (C) 2016 by sysmocom - s.f.m.c. GmbH <info@sysmocom.de> |
| * Authors: Neels Hofmeyr <nhofmeyr@sysmocom.de> |
| * All Rights Reserved |
| * |
| * SPDX-License-Identifier: GPL-2.0+ |
| * |
| * 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. |
| * |
| */ |
| |
| /*! \addtogroup timer |
| * @{ |
| * \file timer_gettimeofday.c |
| * Overriding Time: osmo_gettimeofday() |
| * - Useful to write and reproduce tests that depend on specific time |
| * factors. This API allows to fake the timeval provided by `gettimeofday()` |
| * by using a small shim osmo_gettimeofday(). |
| * - If the clock override is disabled (default) for a given clock, |
| * osmo_gettimeofday() will do the same as regular `gettimeofday()`. |
| * - If you want osmo_gettimeofday() to provide a specific time, you must |
| * enable time override by setting the global variable |
| * osmo_gettimeofday_override (`osmo_gettimeofday_override = true`), then |
| * set the global struct timeval osmo_gettimeofday_override_time wih the |
| * desired value. Next time osmo_gettimeofday() is called, it will return |
| * the values previously set. |
| * - A helper osmo_gettimeofday_override_add() is provided to easily |
| * increment osmo_gettimeofday_override_time with a specific amount of |
| * time. |
| */ |
| |
| #include <stdbool.h> |
| #include <sys/time.h> |
| #include <osmocom/core/timer_compat.h> |
| |
| bool osmo_gettimeofday_override = false; |
| struct timeval osmo_gettimeofday_override_time = { 23, 424242 }; |
| |
| /*! 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. |
| * |
| * N. B: gettimeofday() is affected by discontinuous jumps in the system time |
| * (e.g., if the system administrator manually changes the system time). |
| * Hence this should NEVER be used for elapsed time computation. |
| * Instead, osmo_clock_gettime() with CLOCK_MONOTONIC should be used for that. |
| */ |
| int osmo_gettimeofday(struct timeval *tv, struct timezone *tz) |
| { |
| if (osmo_gettimeofday_override) { |
| *tv = osmo_gettimeofday_override_time; |
| return 0; |
| } |
| |
| return gettimeofday(tv, tz); |
| } |
| |
| /*! 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); |
| } |
| |
| /*! @} */ |