1 /* Enqueue and list of read or write requests.
2 Copyright (C) 1997, 1998, 1999, 2000, 2001 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. */
30 /* We need this special structure to handle asynchronous I/O. */
34 struct sigevent sigev
;
35 struct waitlist list
[0];
40 lio_listio (mode
, list
, nent
, sig
)
42 struct aiocb
*const list
[];
46 struct sigevent defsigev
;
47 struct requestlist
*requests
[nent
];
49 volatile int total
= 0;
52 /* Check arguments. */
53 if (mode
!= LIO_WAIT
&& mode
!= LIO_NOWAIT
)
61 defsigev
.sigev_notify
= SIGEV_NONE
;
65 /* Request the mutex. */
66 pthread_mutex_lock (&__aio_requests_mutex
);
68 /* Now we can enqueue all requests. Since we already acquired the
69 mutex the enqueue function need not do this. */
70 for (cnt
= 0; cnt
< nent
; ++cnt
)
71 if (list
[cnt
] != NULL
&& list
[cnt
]->aio_lio_opcode
!= LIO_NOP
)
73 list
[cnt
]->aio_sigevent
.sigev_notify
= SIGEV_NONE
;
74 requests
[cnt
] = __aio_enqueue_request ((aiocb_union
*) list
[cnt
],
75 list
[cnt
]->aio_lio_opcode
);
77 if (requests
[cnt
] != NULL
)
78 /* Successfully enqueued. */
81 /* Signal that we've seen an error. `errno' and the error code
82 of the aiocb will tell more. */
90 /* We don't have anything to do except signalling if we work
93 /* Release the mutex. We do this before raising a signal since the
94 signal handler might do a `siglongjmp' and then the mutex is
96 pthread_mutex_unlock (&__aio_requests_mutex
);
98 if (mode
== LIO_NOWAIT
)
99 __aio_notify_only (sig
,
100 sig
->sigev_notify
== SIGEV_SIGNAL
? getpid () : 0);
104 else if (mode
== LIO_WAIT
)
106 pthread_cond_t cond
= PTHREAD_COND_INITIALIZER
;
107 struct waitlist waitlist
[nent
];
111 for (cnt
= 0; cnt
< nent
; ++cnt
)
113 assert (requests
[cnt
] == NULL
|| list
[cnt
] != NULL
);
115 if (requests
[cnt
] != NULL
&& list
[cnt
]->aio_lio_opcode
!= LIO_NOP
)
117 waitlist
[cnt
].cond
= &cond
;
118 waitlist
[cnt
].next
= requests
[cnt
]->waiting
;
119 waitlist
[cnt
].counterp
= &total
;
120 waitlist
[cnt
].sigevp
= NULL
;
121 waitlist
[cnt
].caller_pid
= 0; /* Not needed. */
122 requests
[cnt
]->waiting
= &waitlist
[cnt
];
127 /* Since `pthread_cond_wait'/`pthread_cond_timedwait' are cancelation
128 points we must be careful. We added entries to the waiting lists
129 which we must remove. So defer cancelation for now. */
130 pthread_setcancelstate (PTHREAD_CANCEL_DISABLE
, &oldstate
);
133 pthread_cond_wait (&cond
, &__aio_requests_mutex
);
135 /* Now it's time to restore the cancelation state. */
136 pthread_setcancelstate (oldstate
, NULL
);
138 /* Release the conditional variable. */
139 if (pthread_cond_destroy (&cond
) != 0)
140 /* This must never happen. */
145 struct async_waitlist
*waitlist
;
147 waitlist
= (struct async_waitlist
*)
148 malloc (sizeof (struct async_waitlist
)
149 + (nent
* sizeof (struct waitlist
)));
151 if (waitlist
== NULL
)
153 __set_errno (EAGAIN
);
158 pid_t caller_pid
= sig
->sigev_notify
== SIGEV_SIGNAL
? getpid () : 0;
161 for (cnt
= 0; cnt
< nent
; ++cnt
)
163 assert (requests
[cnt
] == NULL
|| list
[cnt
] != NULL
);
165 if (requests
[cnt
] != NULL
166 && list
[cnt
]->aio_lio_opcode
!= LIO_NOP
)
168 waitlist
->list
[cnt
].cond
= NULL
;
169 waitlist
->list
[cnt
].next
= requests
[cnt
]->waiting
;
170 waitlist
->list
[cnt
].counterp
= &waitlist
->counter
;
171 waitlist
->list
[cnt
].sigevp
= &waitlist
->sigev
;
172 waitlist
->list
[cnt
].caller_pid
= caller_pid
;
173 requests
[cnt
]->waiting
= &waitlist
->list
[cnt
];
178 waitlist
->counter
= total
;
179 waitlist
->sigev
= *sig
;
183 /* Release the mutex. */
184 pthread_mutex_unlock (&__aio_requests_mutex
);