1 /* Suspend until termination of a requests.
2 Copyright (C) 1997 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4 Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
6 The GNU C Library is free software; you can redistribute it and/or
7 modify it under the terms of the GNU Library General Public License as
8 published by the Free Software Foundation; either version 2 of the
9 License, or (at your option) any later version.
11 The GNU C Library is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 Library General Public License for more details.
16 You should have received a copy of the GNU Library General Public
17 License along with the GNU C Library; see the file COPYING.LIB. If not,
18 write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
19 Boston, MA 02111-1307, USA. */
22 /* We use an UGLY hack to prevent gcc from finding us cheating. The
23 implementation of aio_suspend and aio_suspend64 are identical and so
24 we want to avoid code duplication by using aliases. But gcc sees
25 the different parameter lists and prints a warning. We define here
26 a function so that aio_suspend64 has no prototype. */
27 #define aio_suspend64 XXX
29 /* And undo the hack. */
38 aio_suspend (list
, nent
, timeout
)
39 const struct aiocb
*const list
[];
41 const struct timespec
*timeout
;
44 struct waitlist waitlist
[nent
];
45 struct requestlist
*requestlist
[nent
];
49 /* Request the mutex. */
50 pthread_mutex_lock (&__aio_requests_mutex
);
52 /* First look whether there is already a terminated request. */
53 for (cnt
= 0; cnt
< nent
; ++cnt
)
54 if (list
[cnt
] != NULL
&& list
[cnt
]->__error_code
!= EINPROGRESS
)
61 /* There is not yet a finished request. Signal the request that
62 we are working for it. */
63 for (cnt
= 0; cnt
< nent
; ++cnt
)
64 if (list
[cnt
] != NULL
&& list
[cnt
]->__error_code
== EINPROGRESS
)
66 requestlist
[cnt
] = __aio_find_req ((aiocb_union
*) list
[cnt
]);
68 if (requestlist
[cnt
] != NULL
)
70 waitlist
[cnt
].cond
= &cond
;
71 waitlist
[cnt
].next
= requestlist
[cnt
]->waiting
;
72 waitlist
[cnt
].counterp
= NULL
;
73 waitlist
[cnt
].sigevp
= NULL
;
74 requestlist
[cnt
]->waiting
= &waitlist
[cnt
];
78 /* Since `pthread_cond_wait'/`pthread_cond_timedwait' are cancelation
79 points we must be careful. We added entries to the waiting lists
80 which we must remove. So defer cancelation for now. */
81 pthread_setcancelstate (PTHREAD_CANCEL_DISABLE
, &oldstate
);
84 result
= pthread_cond_wait (&cond
, &__aio_requests_mutex
);
86 result
= pthread_cond_timedwait (&cond
, &__aio_requests_mutex
,
89 /* Now remove the entry in the waiting list for all requests
90 which didn't terminate */
91 for (cnt
= 0; cnt
< nent
; ++cnt
)
92 if (list
[cnt
] != NULL
&& list
[cnt
]->__error_code
== EINPROGRESS
93 && requestlist
[cnt
] != NULL
)
95 struct waitlist
**listp
= &requestlist
[cnt
]->waiting
;
97 /* There is the chance that we cannot find our entry anymore.
98 This could happen if the request terminated and restarted
100 while (*listp
!= NULL
&& *listp
!= &waitlist
[cnt
])
101 listp
= &(*listp
)->next
;
104 *listp
= (*listp
)->next
;
107 /* Now it's time to restore the cancelation state. */
108 pthread_setcancelstate (oldstate
, NULL
);
112 /* An error occurred. Possibly it's EINTR. We have to translate
113 the timeout error report of `pthread_cond_timedwait' to the
114 form expected from `aio_suspend'. */
115 if (result
== ETIMEDOUT
)
116 __set_errno (EAGAIN
);
122 /* Release the mutex. */
123 pthread_mutex_unlock (&__aio_requests_mutex
);
128 weak_alias (aio_suspend
, aio_suspend64
)