| /* Suspend until termination of a requests. |
| Copyright (C) 1997, 1998 Free Software Foundation, Inc. |
| This file is part of the GNU C Library. |
| Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997. |
| |
| The GNU C Library is free software; you can redistribute it and/or |
| modify it under the terms of the GNU Library General Public License as |
| published by the Free Software Foundation; either version 2 of the |
| License, or (at your option) any later version. |
| |
| The GNU C 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 |
| Library General Public License for more details. |
| |
| You should have received a copy of the GNU Library General Public |
| License along with the GNU C Library; see the file COPYING.LIB. If not, |
| write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, |
| Boston, MA 02111-1307, USA. */ |
| |
| |
| /* We use an UGLY hack to prevent gcc from finding us cheating. The |
| implementation of aio_suspend and aio_suspend64 are identical and so |
| we want to avoid code duplication by using aliases. But gcc sees |
| the different parameter lists and prints a warning. We define here |
| a function so that aio_suspend64 has no prototype. */ |
| #define aio_suspend64 XXX |
| #include <aio.h> |
| /* And undo the hack. */ |
| #undef aio_suspend64 |
| |
| #include <errno.h> |
| |
| #include "aio_misc.h" |
| |
| |
| int |
| aio_suspend (list, nent, timeout) |
| const struct aiocb *const list[]; |
| int nent; |
| const struct timespec *timeout; |
| { |
| struct waitlist waitlist[nent]; |
| struct requestlist *requestlist[nent]; |
| pthread_cond_t cond = PTHREAD_COND_INITIALIZER; |
| int cnt; |
| int result = 0; |
| int dummy; |
| int none = 1; |
| |
| /* Request the mutex. */ |
| pthread_mutex_lock (&__aio_requests_mutex); |
| |
| /* There is not yet a finished request. Signal the request that |
| we are working for it. */ |
| for (cnt = 0; cnt < nent; ++cnt) |
| if (list[cnt] != NULL && list[cnt]->__error_code == EINPROGRESS) |
| { |
| requestlist[cnt] = __aio_find_req ((aiocb_union *) list[cnt]); |
| |
| if (requestlist[cnt] != NULL) |
| { |
| waitlist[cnt].cond = &cond; |
| waitlist[cnt].next = requestlist[cnt]->waiting; |
| waitlist[cnt].counterp = &dummy; |
| waitlist[cnt].sigevp = NULL; |
| requestlist[cnt]->waiting = &waitlist[cnt]; |
| none = 0; |
| } |
| } |
| |
| /* If there is a not finished request wait for it. */ |
| if (!none) |
| { |
| int oldstate; |
| |
| /* Since `pthread_cond_wait'/`pthread_cond_timedwait' are cancelation |
| points we must be careful. We added entries to the waiting lists |
| which we must remove. So defer cancelation for now. */ |
| pthread_setcancelstate (PTHREAD_CANCEL_DISABLE, &oldstate); |
| |
| if (timeout == NULL) |
| result = pthread_cond_wait (&cond, &__aio_requests_mutex); |
| else |
| result = pthread_cond_timedwait (&cond, &__aio_requests_mutex, |
| timeout); |
| |
| /* Now remove the entry in the waiting list for all requests |
| which didn't terminate. */ |
| for (cnt = 0; cnt < nent; ++cnt) |
| if (list[cnt] != NULL && list[cnt]->__error_code == EINPROGRESS |
| && requestlist[cnt] != NULL) |
| { |
| struct waitlist **listp = &requestlist[cnt]->waiting; |
| |
| /* There is the chance that we cannot find our entry anymore. |
| This could happen if the request terminated and restarted |
| again. */ |
| while (*listp != NULL && *listp != &waitlist[cnt]) |
| listp = &(*listp)->next; |
| |
| if (*listp != NULL) |
| *listp = (*listp)->next; |
| } |
| |
| /* Now it's time to restore the cancelation state. */ |
| pthread_setcancelstate (oldstate, NULL); |
| |
| /* Release the conditional variable. */ |
| if (pthread_cond_destroy (&cond) != 0) |
| /* This must never happen. */ |
| abort (); |
| |
| if (result != 0) |
| { |
| /* An error occurred. Possibly it's EINTR. We have to translate |
| the timeout error report of `pthread_cond_timedwait' to the |
| form expected from `aio_suspend'. */ |
| if (result == ETIMEDOUT) |
| __set_errno (EAGAIN); |
| |
| result = -1; |
| } |
| } |
| |
| /* Release the mutex. */ |
| pthread_mutex_unlock (&__aio_requests_mutex); |
| |
| return result; |
| } |
| |
| weak_alias (aio_suspend, aio_suspend64) |