yolobs-studio/deps/w32-pthreads/pthread_delay_np.c
2016-02-24 00:16:51 +01:00

172 lines
4.8 KiB
C

/*
* pthreads_delay_np.c
*
* Description:
* This translation unit implements non-portable thread functions.
*
* --------------------------------------------------------------------------
*
* Pthreads-win32 - POSIX Threads Library for Win32
* Copyright(C) 1998 John E. Bossom
* Copyright(C) 1999,2005 Pthreads-win32 contributors
*
* Contact Email: rpj@callisto.canberra.edu.au
*
* The current list of contributors is contained
* in the file CONTRIBUTORS included with the source
* code distribution. The list can also be seen at the
* following World Wide Web location:
* http://sources.redhat.com/pthreads-win32/contributors.html
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library in the file COPYING.LIB;
* if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
*/
#include "pthread.h"
#include "implement.h"
/*
* pthread_delay_np
*
* DESCRIPTION
*
* This routine causes a thread to delay execution for a specific period of time.
* This period ends at the current time plus the specified interval. The routine
* will not return before the end of the period is reached, but may return an
* arbitrary amount of time after the period has gone by. This can be due to
* system load, thread priorities, and system timer granularity.
*
* Specifying an interval of zero (0) seconds and zero (0) nanoseconds is
* allowed and can be used to force the thread to give up the processor or to
* deliver a pending cancelation request.
*
* The timespec structure contains the following two fields:
*
* tv_sec is an integer number of seconds.
* tv_nsec is an integer number of nanoseconds.
*
* Return Values
*
* If an error condition occurs, this routine returns an integer value indicating
* the type of error. Possible return values are as follows:
*
* 0
* Successful completion.
* [EINVAL]
* The value specified by interval is invalid.
*
* Example
*
* The following code segment would wait for 5 and 1/2 seconds
*
* struct timespec tsWait;
* int intRC;
*
* tsWait.tv_sec = 5;
* tsWait.tv_nsec = 500000000L;
* intRC = pthread_delay_np(&tsWait);
*/
int
pthread_delay_np (struct timespec *interval)
{
DWORD wait_time;
DWORD secs_in_millisecs;
DWORD millisecs;
DWORD status;
pthread_t self;
ptw32_thread_t * sp;
if (interval == NULL)
{
return EINVAL;
}
if (interval->tv_sec == 0L && interval->tv_nsec == 0L)
{
pthread_testcancel ();
Sleep (0);
pthread_testcancel ();
return (0);
}
/* convert secs to millisecs */
secs_in_millisecs = (DWORD)interval->tv_sec * 1000L;
/* convert nanosecs to millisecs (rounding up) */
millisecs = (interval->tv_nsec + 999999L) / 1000000L;
#if defined(__WATCOMC__)
#pragma disable_message (124)
#endif
/*
* Most compilers will issue a warning 'comparison always 0'
* because the variable type is unsigned, but we need to keep this
* for some reason I can't recall now.
*/
if (0 > (wait_time = secs_in_millisecs + millisecs))
{
return EINVAL;
}
#if defined(__WATCOMC__)
#pragma enable_message (124)
#endif
if (NULL == (self = pthread_self ()).p)
{
return ENOMEM;
}
sp = (ptw32_thread_t *) self.p;
if (sp->cancelState == PTHREAD_CANCEL_ENABLE)
{
/*
* Async cancelation won't catch us until wait_time is up.
* Deferred cancelation will cancel us immediately.
*/
if (WAIT_OBJECT_0 ==
(status = WaitForSingleObject (sp->cancelEvent, wait_time)))
{
ptw32_mcs_local_node_t stateLock;
/*
* Canceling!
*/
ptw32_mcs_lock_acquire (&sp->stateLock, &stateLock);
if (sp->state < PThreadStateCanceling)
{
sp->state = PThreadStateCanceling;
sp->cancelState = PTHREAD_CANCEL_DISABLE;
ptw32_mcs_lock_release (&stateLock);
ptw32_throw (PTW32_EPS_CANCEL);
}
ptw32_mcs_lock_release (&stateLock);
return ESRCH;
}
else if (status != WAIT_TIMEOUT)
{
return EINVAL;
}
}
else
{
Sleep (wait_time);
}
return (0);
}