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58 lines
1.9 KiB
C
58 lines
1.9 KiB
C
/* io_getevents.c
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libaio Linux async I/O interface
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Copyright 2002 Red Hat, Inc.
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This library is free software; you can redistribute it and/or
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modify it under the terms of the GNU Lesser General Public
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License as published by the Free Software Foundation; either
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version 2 of the License, or (at your option) any later version.
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This library is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public
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License along with this library; if not, write to the Free Software
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Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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*/
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#include <libaio.h>
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#include <errno.h>
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#include <stdlib.h>
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#include <time.h>
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#include "syscall.h"
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io_syscall5(int, __io_getevents_0_4, io_getevents, io_context_t, ctx, long, min_nr, long, nr, struct io_event *, events, struct timespec *, timeout)
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#define AIO_RING_MAGIC 0xa10a10a1
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/* Ben will hate me for this */
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struct aio_ring {
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unsigned id; /* kernel internal index number */
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unsigned nr; /* number of io_events */
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unsigned head;
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unsigned tail;
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unsigned magic;
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unsigned compat_features;
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unsigned incompat_features;
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unsigned header_length; /* size of aio_ring */
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};
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int io_getevents_0_4(io_context_t ctx, long min_nr, long nr, struct io_event * events, struct timespec * timeout)
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{
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struct aio_ring *ring;
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ring = (struct aio_ring*)ctx;
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if (ring==NULL || ring->magic != AIO_RING_MAGIC)
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goto do_syscall;
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if (timeout!=NULL && timeout->tv_sec == 0 && timeout->tv_nsec == 0) {
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if (ring->head == ring->tail)
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return 0;
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}
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do_syscall:
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return __io_getevents_0_4(ctx, min_nr, nr, events, timeout);
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}
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DEFSYMVER(io_getevents_0_4, io_getevents, 0.4)
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