1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
|
#include "pthread_impl.h"
struct cm {
pthread_cond_t *c;
pthread_mutex_t *m;
};
static void unwait(pthread_cond_t *c, pthread_mutex_t *m)
{
/* Removing a waiter is non-trivial if we could be using requeue
* based broadcast signals, due to mutex access issues, etc. */
if (c->_c_mutex == (void *)-1) {
a_dec(&c->_c_waiters);
if (c->_c_destroy) __wake(&c->_c_waiters, 1, 0);
return;
}
while (a_swap(&c->_c_lock, 1))
__wait(&c->_c_lock, &c->_c_lockwait, 1, 1);
if (c->_c_waiters2) c->_c_waiters2--;
else a_dec(&m->_m_waiters);
a_store(&c->_c_lock, 0);
if (c->_c_lockwait) __wake(&c->_c_lock, 1, 1);
a_dec(&c->_c_waiters);
if (c->_c_destroy) __wake(&c->_c_waiters, 1, 1);
}
static void cleanup(void *p)
{
struct cm *cm = p;
unwait(cm->c, cm->m);
pthread_mutex_lock(cm->m);
}
int pthread_cond_timedwait(pthread_cond_t *restrict c, pthread_mutex_t *restrict m, const struct timespec *restrict ts)
{
struct cm cm = { .c=c, .m=m };
int r, e=0, seq;
if (m->_m_type && (m->_m_lock&INT_MAX) != pthread_self()->tid)
return EPERM;
if (ts && ts->tv_nsec >= 1000000000UL)
return EINVAL;
pthread_testcancel();
a_inc(&c->_c_waiters);
if (c->_c_mutex != (void *)-1) {
c->_c_mutex = m;
while (a_swap(&c->_c_lock, 1))
__wait(&c->_c_lock, &c->_c_lockwait, 1, 1);
c->_c_waiters2++;
a_store(&c->_c_lock, 0);
if (c->_c_lockwait) __wake(&c->_c_lock, 1, 1);
}
seq = c->_c_seq;
pthread_mutex_unlock(m);
do e = __timedwait(&c->_c_seq, seq, c->_c_clock, ts, cleanup, &cm, 0);
while (c->_c_seq == seq && (!e || e==EINTR));
if (e == EINTR) e = 0;
unwait(c, m);
if ((r=pthread_mutex_lock(m))) return r;
return e;
}
|