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/* ==== wait.c ============================================================
* Copyright (c) 1994 by Chris Provenzano, proven@mit.edu
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Chris Provenzano.
* 4. The name of Chris Provenzano may not be used to endorse or promote
* products derived from this software without specific prior written
* permission.
*
* THIS SOFTWARE IS PROVIDED BY CHRIS PROVENZANO ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL CHRIS PROVENZANO BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* Description : All the appropriate wait routines.
*
* 1.38 94/06/13 proven
* -Started coding this file.
*
*/
#ifndef lint
static const char rcsid[] = "$Id$";
#endif
#include <pthread.h>
#include <signal.h>
#include <sys/types.h>
#include <sys/time.h>
#include <pthread/posix.h>
#include <sys/compat.h>
#include <sys/wait.h>
/* This is an UGLY hack to get wait to compile, something better is needed. */
/* #define _POSIX_SOURCE
#undef _POSIX_SOURCE
*/
struct pthread_queue wait_queue = { NULL, NULL, NULL };
extern void sig_handler_real();
/* ==========================================================================
* wait_wakeup()
*
* This routine is called by the interrupt handler which has locked
* the current kthread semaphore. Since only threads owned by the
* current kthread can be queue here, no additional locks are necessary.
*/
int wait_wakeup()
{
struct pthread *pthread;
int ret = 0;
if (pthread = pthread_queue_deq(& wait_queue)) {
/* Wakeup all threads, and enqueue them on the run queue */
do {
pthread->state = PS_RUNNING;
if (pthread->pthread_priority > ret) {
ret = pthread->pthread_priority;
}
pthread_prio_queue_enq(pthread_current_prio_queue, pthread);
} while (pthread = pthread_queue_deq(&wait_queue));
return(ret);
}
return(NOTOK);
}
/* ==========================================================================
* For the wait calls, it is important that the current kthread is locked
* before the apropriate wait syscall is preformed. This way we ensure
* that there is never a case where a thread is waiting for a child but
* missed the interrupt for that child.
* Patched by William S. Lear 1997-02-02
*/
/* ==========================================================================
* waitpid()
*/
pid_t waitpid(pid_t pid, int *status, int options)
{
pid_t ret;
pthread_sched_prevent();
ret = machdep_sys_waitpid(pid, status, options | WNOHANG);
/* If we are not doing nohang, try again, else return immediately */
if (!(options & WNOHANG)) {
while (ret == OK) {
/* Enqueue thread on wait queue */
pthread_queue_enq(&wait_queue, pthread_run);
/* reschedule unlocks scheduler */
SET_PF_AT_CANCEL_POINT(pthread_run); /* This is a cancel point */
pthread_resched_resume(PS_WAIT_WAIT);
CLEAR_PF_AT_CANCEL_POINT(pthread_run); /* No longer at cancel point */
pthread_sched_prevent();
ret = machdep_sys_waitpid(pid, status, options | WNOHANG);
}
}
pthread_sched_resume();
return(ret);
}
/* ==========================================================================
* wait3()
* Patched by Monty 1997-02-02
*/
pid_t wait3(__WAIT_STATUS status, int options, void * rusage)
{
semaphore * lock;
pid_t ret;
pthread_sched_prevent();
ret = machdep_sys_wait3(status, options | WNOHANG, rusage);
/* If we are not doing nohang, try again, else return immediately */
if (!(options & WNOHANG)) {
while (ret == OK) {
/* Enqueue thread on wait queue */
pthread_queue_enq(&wait_queue, pthread_run);
/* reschedule unlocks scheduler */
SET_PF_AT_CANCEL_POINT(pthread_run); /* This is a cancel point */
pthread_resched_resume(PS_WAIT_WAIT);
CLEAR_PF_AT_CANCEL_POINT(pthread_run); /* No longer at cancel point */
pthread_sched_prevent();
machdep_sys_wait3(status, options | WNOHANG, rusage);
}
}
pthread_sched_resume();
return(ret);
}
/* ==========================================================================
* wait()
*/
pid_t wait(__WAIT_STATUS status)
{
return(waitpid((pid_t)-1, (int *)status, 0));
}
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