/*
* w32_CancelableWait.c
*
* Description:
* This translation unit implements miscellaneous thread functions.
*
* --------------------------------------------------------------------------
*
* Pthreads-win32 - POSIX Threads Library for Win32
* Copyright(C) 1998 John E. Bossom
* Copyright(C) 1999,2005 Pthreads-win32 contributors
*
* Contact Email: [email protected]
*
* 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"
static INLINE int
ptw32_cancelable_wait (HANDLE waitHandle, DWORD timeout)
/*
* -------------------------------------------------------------------
* This provides an extra hook into the pthread_cancel
* mechanism that will allow you to wait on a Windows handle and make it a
* cancellation point. This function blocks until the given WIN32 handle is
* signaled or pthread_cancel has been called. It is implemented using
* WaitForMultipleObjects on 'waitHandle' and a manually reset WIN32
* event used to implement pthread_cancel.
*
* Given this hook it would be possible to implement more of the cancellation
* points.
* -------------------------------------------------------------------
*/
{
int result;
pthread_t self;
ptw32_thread_t * sp;
HANDLE handles[2];
DWORD nHandles = 1;
DWORD status;
handles[0] = waitHandle;
self = pthread_self();
sp = (ptw32_thread_t *) self.p;
if (sp != NULL)
{
/*
* Get cancelEvent handle
*/
if (sp->cancelState == PTHREAD_CANCEL_ENABLE)
{
if ((handles[1] = sp->cancelEvent) != NULL)
{
nHandles++;
}
}
}
else
{
handles[1] = NULL;
}
status = WaitForMultipleObjects (nHandles, handles, PTW32_FALSE, timeout);
switch (status - WAIT_OBJECT_0)
{
case 0:
/*
* Got the handle.
* In the event that both handles are signalled, the smallest index
* value (us) is returned. As it has been arranged, this ensures that
* we don't drop a signal that we should act on (i.e. semaphore,
* mutex, or condition variable etc).
*/
result = 0;
break;
case 1:
/*
* Got cancel request.
* In the event that both handles are signaled, the cancel will
* be ignored (see case 0 comment).
*/
ResetEvent (handles[1]);
if (sp != NULL)
{
ptw32_mcs_local_node_t stateLock;
/*
* Should handle POSIX and implicit POSIX threads..
* Make sure we haven't been async-canceled in the meantime.
*/
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);
/* Never reached */
}
ptw32_mcs_lock_release (&stateLock);
}
/* Should never get to here. */
result = EINVAL;
break;
default:
if (status == WAIT_TIMEOUT)
{
result = ETIMEDOUT;
}
else
{
result = EINVAL;
}
break;
}
return (result);
} /* CancelableWait */
int
pthreadCancelableWait (HANDLE waitHandle)
{
return (ptw32_cancelable_wait (waitHandle, INFINITE));
}
int
pthreadCancelableTimedWait (HANDLE waitHandle, DWORD timeout)
{
return (ptw32_cancelable_wait (waitHandle, timeout));
}
Codebase Browser
chromium