obs-studio/deps/w32-pthreads/pthread_setcancelstate.c

126 lines
4.0 KiB
C

/*
* pthread_setcancelstate.c
*
* Description:
* POSIX thread functions related to thread cancellation.
*
* --------------------------------------------------------------------------
*
* 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.,
* 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
*/
#include "pthread.h"
#include "implement.h"
int
pthread_setcancelstate (int state, int *oldstate)
/*
* ------------------------------------------------------
* DOCPUBLIC
* This function atomically sets the calling thread's
* cancelability state to 'state' and returns the previous
* cancelability state at the location referenced by
* 'oldstate'
*
* PARAMETERS
* state,
* oldstate
* PTHREAD_CANCEL_ENABLE
* cancellation is enabled,
*
* PTHREAD_CANCEL_DISABLE
* cancellation is disabled
*
*
* DESCRIPTION
* This function atomically sets the calling thread's
* cancelability state to 'state' and returns the previous
* cancelability state at the location referenced by
* 'oldstate'.
*
* NOTES:
* 1) Use to disable cancellation around 'atomic' code that
* includes cancellation points
*
* COMPATIBILITY ADDITIONS
* If 'oldstate' is NULL then the previous state is not returned
* but the function still succeeds. (Solaris)
*
* RESULTS
* 0 successfully set cancelability type,
* EINVAL 'state' is invalid
*
* ------------------------------------------------------
*/
{
ptw32_mcs_local_node_t stateLock;
int result = 0;
pthread_t self = pthread_self ();
ptw32_thread_t * sp = (ptw32_thread_t *) self.p;
if (sp == NULL
|| (state != PTHREAD_CANCEL_ENABLE && state != PTHREAD_CANCEL_DISABLE))
{
return EINVAL;
}
/*
* Lock for async-cancel safety.
*/
ptw32_mcs_lock_acquire (&sp->stateLock, &stateLock);
if (oldstate != NULL)
{
*oldstate = sp->cancelState;
}
sp->cancelState = state;
/*
* Check if there is a pending asynchronous cancel
*/
if (state == PTHREAD_CANCEL_ENABLE
&& sp->cancelType == PTHREAD_CANCEL_ASYNCHRONOUS
&& WaitForSingleObject (sp->cancelEvent, 0) == WAIT_OBJECT_0)
{
sp->state = PThreadStateCanceling;
sp->cancelState = PTHREAD_CANCEL_DISABLE;
ResetEvent (sp->cancelEvent);
ptw32_mcs_lock_release (&stateLock);
ptw32_throw (PTW32_EPS_CANCEL);
/* Never reached */
}
ptw32_mcs_lock_release (&stateLock);
return (result);
} /* pthread_setcancelstate */