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#include <aio.h>
#include <errno.h>
#include <time.h>
#include "atomic.h"
#include "libc.h"
#include "pthread_impl.h"
extern volatile int __aio_fut;
int aio_suspend(const struct aiocb *const cbs[], int cnt, const struct timespec *ts)
{
int i, tid = 0, ret, expect = 0;
struct timespec at;
volatile int dummy_fut, *pfut;
int nzcnt = 0;
const struct aiocb *cb = 0;
if (cnt<0) {
errno = EINVAL;
return -1;
}
for (i=0; i<cnt; i++) if (cbs[i]) {
if (aio_error(cbs[i]) != EINPROGRESS) return 0;
nzcnt++;
cb = cbs[i];
}
if (ts) {
clock_gettime(CLOCK_MONOTONIC, &at);
at.tv_sec += ts->tv_sec;
if ((at.tv_nsec += ts->tv_nsec) >= 1000000000) {
at.tv_nsec -= 1000000000;
at.tv_sec++;
}
}
for (;;) {
for (i=0; i<cnt; i++)
if (cbs[i] && aio_error(cbs[i]) != EINPROGRESS)
return 0;
switch (nzcnt) {
case 0:
pfut = &dummy_fut;
break;
case 1:
pfut = (void *)&cb->__err;
expect = EINPROGRESS | 0x80000000;
a_cas(pfut, EINPROGRESS, expect);
break;
default:
pfut = &__aio_fut;
if (!tid) tid = __pthread_self()->tid;
expect = a_cas(pfut, 0, tid);
if (!expect) expect = tid;
/* Need to recheck the predicate before waiting. */
for (i=0; i<cnt; i++)
if (cbs[i] && aio_error(cbs[i]) != EINPROGRESS)
return 0;
break;
}
ret = __timedwait(pfut, expect, CLOCK_MONOTONIC, ts?&at:0, 0, 0, 1);
if (ret) {
errno = ret==ETIMEDOUT ? EAGAIN : ret;
return -1;
}
}
}
LFS64(aio_suspend);
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