incubator-nuttx/sched/timer/timer_getitimer.c

114 lines
4.1 KiB
C

/****************************************************************************
* sched/timer/timer_getitimer.c
*
* Copyright (C) 2019 Xiaomi Inc. All rights reserved.
* Author: Xiang Xiao <xiaoxiang@xiaomi.com>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <errno.h>
#include <time.h>
#include <sys/time.h>
#include "sched/sched.h"
#ifndef CONFIG_DISABLE_POSIX_TIMERS
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: getitimer
*
* Description:
* The getitimer() function will store the amount of time until the
* specified timer, which, expires and the reload value of the timer
* into the space pointed to by the value argument. The it_value member
* of this structure will contain the amount of time before the timer
* expires, or zero if the timer is disarmed. This value is returned as
* the interval until timer expiration. The it_interval member of value
* will contain the reload value last set by setitime().
*
* Input Parameters:
* which - The predefined timer id
* value - The current timer value
*
* Returned Value:
* If the getitimer() succeeds, a value of 0 (OK) will be returned.
* If an error occurs, the value -1 (ERROR) will be returned, and errno
* set to indicate the error.
*
* EINVAL - The which argument does not correspond to an predefined ID.
*
* Assumptions/Limitations:
* Due to the asynchronous operation of this function, the time reported
* by this function could be significantly more than that actual time
* remaining on the timer at any time.
*
****************************************************************************/
int getitimer(int which, FAR struct itimerval *value)
{
FAR struct tcb_s *rtcb = this_task();
struct itimerspec spec =
{
};
int ret = OK;
if (which != ITIMER_REAL || !value)
{
set_errno(EINVAL);
return ERROR;
}
if (rtcb->group->itimer)
{
ret = timer_gettime(rtcb->group->itimer, &spec);
}
if (ret == OK)
{
TIMESPEC_TO_TIMEVAL(&value->it_value, &spec.it_value);
TIMESPEC_TO_TIMEVAL(&value->it_interval, &spec.it_interval);
}
return ret;
}
#endif /* CONFIG_DISABLE_POSIX_TIMERS */