incubator-nuttx/sched/signal/sig_sleep.c

109 lines
3.5 KiB
C

/****************************************************************************
* sched/signal/sig_sleep.c
*
* SPDX-License-Identifier: Apache-2.0
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you 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.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <signal.h>
#include <nuttx/clock.h>
#include <nuttx/signal.h>
#include <arch/irq.h>
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: nxsig_sleep
*
* Description:
* The nxsig_sleep() function will cause the calling thread to be
* suspended from execution until either the number of real-time seconds
* specified by the argument 'seconds' has elapsed or a signal is
* delivered to the calling thread.
*
* This is an internal OS interface. It is functionally equivalent to
* the standard sleep() application interface except that:
*
* - It is not a cancellation point, and
* - There is no check that the action of the signal is to invoke a
* signal-catching function or to terminate the process.
*
* See the description of sleep() for additional information that is not
* duplicated here.
*
* Input Parameters:
* seconds - The number of seconds to sleep
*
* Returned Value:
* If nxsig_sleep() returns because the requested time has elapsed, the
* value returned will be zero (OK). If nxsig_sleep() returns because of
* premature arousal due to delivery of a signal, the return value will
* be the "unslept" amount (the requested time minus the time actually
* slept) in seconds.
*
****************************************************************************/
unsigned int nxsig_sleep(unsigned int seconds)
{
struct timespec rqtp;
struct timespec rmtp;
unsigned int remaining = 0;
int ret;
/* Don't sleep if seconds == 0 */
if (seconds > 0)
{
/* Let nxsig_nanosleep() do all of the work. */
rqtp.tv_sec = seconds;
rqtp.tv_nsec = 0;
ret = nxsig_nanosleep(&rqtp, &rmtp);
/* nanosleep() should only fail if it was interrupted by a signal,
* but we treat all errors the same,
*/
if (ret < 0)
{
remaining = rmtp.tv_sec;
if (remaining < seconds && rmtp.tv_nsec >= 500000000)
{
/* Round up */
remaining++;
}
}
return remaining;
}
return 0;
}