87 lines
3.0 KiB
C
87 lines
3.0 KiB
C
/****************************************************************************
|
|
* sched/signal/sig_usleep.c
|
|
*
|
|
* 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 <sys/types.h>
|
|
#include <unistd.h>
|
|
#include <signal.h>
|
|
#include <assert.h>
|
|
#include <errno.h>
|
|
|
|
#include <nuttx/signal.h>
|
|
|
|
/****************************************************************************
|
|
* Public Functions
|
|
****************************************************************************/
|
|
|
|
/****************************************************************************
|
|
* Name: nxsig_usleep
|
|
*
|
|
* Description:
|
|
* The nxsig_usleep() function will cause the calling thread to be
|
|
* suspended from execution until either the number of real-time
|
|
* microseconds specified by the argument 'usec' has elapsed or a signal
|
|
* is delivered to the calling thread. The suspension time may be longer
|
|
* than requested due to the scheduling of other activity by the system.
|
|
*
|
|
* This is an internal OS interface. It is functionally equivalent to
|
|
* the standard nxsig_usleep() application interface except that:
|
|
*
|
|
* - It is not a cancellation point, and
|
|
* - It does not modify the errno value.
|
|
*
|
|
* See the description of usleep() for additional information that is not
|
|
* duplicated here.
|
|
*
|
|
* Input Parameters:
|
|
* usec - the number of microseconds to wait.
|
|
*
|
|
* Returned Value:
|
|
* This is an internal OS interface and should not be used by applications.
|
|
* It follows the NuttX internal error return policy: Zero (OK) is
|
|
* returned on success. A negated errno value is returned on failure.
|
|
*
|
|
****************************************************************************/
|
|
|
|
int nxsig_usleep(useconds_t usec)
|
|
{
|
|
struct timespec rqtp;
|
|
time_t sec;
|
|
int ret = 0;
|
|
|
|
if (usec)
|
|
{
|
|
/* Let nxsig_nanosleep() do all of the work. */
|
|
|
|
sec = usec / 1000000;
|
|
rqtp.tv_sec = sec;
|
|
rqtp.tv_nsec = (usec - (sec * 1000000)) * 1000;
|
|
|
|
ret = nxsig_nanosleep(&rqtp, NULL);
|
|
}
|
|
|
|
return ret;
|
|
}
|