| /* |
| * pthread_timechange_handler_np.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: 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" |
| |
| /* |
| * Notes on handling system time adjustments (especially negative ones). |
| * --------------------------------------------------------------------- |
| * |
| * This solution was suggested by Alexander Terekhov, but any errors |
| * in the implementation are mine - [Ross Johnson] |
| * |
| * 1) The problem: threads doing a timedwait on a CV may expect to timeout |
| * at a specific absolute time according to a system timer. If the |
| * system clock is adjusted backwards then those threads sleep longer than |
| * expected. Also, pthreads-win32 converts absolute times to intervals in |
| * order to make use of the underlying Win32, and so waiting threads may |
| * awake before their proper abstimes. |
| * |
| * 2) We aren't able to distinquish between threads on timed or untimed waits, |
| * so we wake them all at the time of the adjustment so that they can |
| * re-evaluate their conditions and re-compute their timeouts. |
| * |
| * 3) We rely on correctly written applications for this to work. Specifically, |
| * they must be able to deal properly with spurious wakeups. That is, |
| * they must re-test their condition upon wakeup and wait again if |
| * the condition is not satisfied. |
| */ |
| |
| void * |
| pthread_timechange_handler_np (void *arg) |
| /* |
| * ------------------------------------------------------ |
| * DOCPUBLIC |
| * Broadcasts all CVs to force re-evaluation and |
| * new timeouts if required. |
| * |
| * PARAMETERS |
| * NONE |
| * |
| * |
| * DESCRIPTION |
| * Broadcasts all CVs to force re-evaluation and |
| * new timeouts if required. |
| * |
| * This routine may be passed directly to pthread_create() |
| * as a new thread in order to run asynchronously. |
| * |
| * |
| * RESULTS |
| * 0 successfully broadcast all CVs |
| * EAGAIN Not all CVs were broadcast |
| * |
| * ------------------------------------------------------ |
| */ |
| { |
| int result = 0; |
| pthread_cond_t cv; |
| |
| EnterCriticalSection (&ptw32_cond_list_lock); |
| |
| cv = ptw32_cond_list_head; |
| |
| while (cv != NULL && 0 == result) |
| { |
| result = pthread_cond_broadcast (&cv); |
| cv = cv->next; |
| } |
| |
| LeaveCriticalSection (&ptw32_cond_list_lock); |
| |
| return (void *) (result != 0 ? EAGAIN : 0); |
| } |