1#include <aio.h>
 2#include <errno.h>
 3#include <time.h>
 4#include "atomic.h"
 5#include "pthread_impl.h"
 6#include "aio_impl.h"
 7
 8int aio_suspend(const struct aiocb *const cbs[], int cnt, const struct timespec *ts)
 9{
10	int i, tid = 0, ret, expect = 0;
11	struct timespec at;
12	volatile int dummy_fut = 0, *pfut;
13	int nzcnt = 0;
14	const struct aiocb *cb = 0;
15
16	pthread_testcancel();
17
18	if (cnt<0) {
19		errno = EINVAL;
20		return -1;
21	}
22
23	for (i=0; i<cnt; i++) if (cbs[i]) {
24		if (aio_error(cbs[i]) != EINPROGRESS) return 0;
25		nzcnt++;
26		cb = cbs[i];
27	}
28
29	if (ts) {
30		clock_gettime(CLOCK_MONOTONIC, &at);
31		at.tv_sec += ts->tv_sec;
32		if ((at.tv_nsec += ts->tv_nsec) >= 1000000000) {
33			at.tv_nsec -= 1000000000;
34			at.tv_sec++;
35		}
36	}
37
38	for (;;) {
39		for (i=0; i<cnt; i++)
40			if (cbs[i] && aio_error(cbs[i]) != EINPROGRESS)
41				return 0;
42
43		switch (nzcnt) {
44		case 0:
45			pfut = &dummy_fut;
46			break;
47		case 1:
48			pfut = (void *)&cb->__err;
49			expect = EINPROGRESS | 0x80000000;
50			a_cas(pfut, EINPROGRESS, expect);
51			break;
52		default:
53			pfut = &__aio_fut;
54			if (!tid) tid = __pthread_self()->tid;
55			expect = a_cas(pfut, 0, tid);
56			if (!expect) expect = tid;
57			/* Need to recheck the predicate before waiting. */
58			for (i=0; i<cnt; i++)
59				if (cbs[i] && aio_error(cbs[i]) != EINPROGRESS)
60					return 0;
61			break;
62		}
63
64		ret = __timedwait_cp(pfut, expect, CLOCK_MONOTONIC, ts?&at:0, 1);
65
66		switch (ret) {
67		case ETIMEDOUT:
68			ret = EAGAIN;
69		case ECANCELED:
70		case EINTR:
71			errno = ret;
72			return -1;
73		}
74	}
75}