1 // sem_wait and sem_timedwait are cancellation points
2 #include <pthread.h>
3 #include <semaphore.h>
4 #include <string.h>
5 #include "test.h"
6
7 #define TESTC(c, m) ( (c) || (t_error("%s failed (" m ")\n", #c), 0) )
8 #define TESTR(r, f, m) ( \
9 ((r) = (f)) == 0 || (t_error("%s failed: %s (" m ")\n", #f, strerror(r)), 0) )
10
11 static sem_t sem1, sem2;
12
13 static int seqno;
14
wait_cancel(void * arg)15 static void wait_cancel(void *arg)
16 {
17 pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, 0);
18 while (sem_wait(&sem1));
19 pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, 0);
20 seqno = 1;
21 }
22
start_sem_wait(void * arg)23 static void *start_sem_wait(void *arg)
24 {
25 wait_cancel(arg);
26 sem_wait(&sem2);
27 seqno = 2;
28 return 0;
29 }
30
start_sem_timedwait(void * arg)31 static void *start_sem_timedwait(void *arg)
32 {
33 wait_cancel(arg);
34 sem_timedwait(&sem2, &(struct timespec){1, 0});
35 seqno = 2;
36 return 0;
37 }
38
main(void)39 int main(void)
40 {
41 pthread_t td;
42 int r;
43 void *res;
44
45 TESTR(r, sem_init(&sem1, 0, 0), "creating semaphore");
46 TESTR(r, sem_init(&sem2, 0, 1), "creating semaphore");
47
48 /* Cancellation on uncontended sem_wait */
49 seqno = 0;
50 TESTR(r, pthread_create(&td, 0, start_sem_wait, 0), "failed to create thread");
51 TESTR(r, pthread_cancel(td), "canceling");
52 sem_post(&sem1);
53 TESTR(r, pthread_join(td, &res), "joining canceled thread after uncontended sem_wait");
54 TESTC(res == PTHREAD_CANCELED, "canceled thread exit status after uncontended sem_wait");
55 TESTC(seqno == 1, "uncontended sem_wait");
56
57 /* Cancellation on blocking sem_wait */
58 seqno = 0;
59 sem_trywait(&sem2);
60 TESTR(r, pthread_create(&td, 0, start_sem_wait, 0), "failed to create thread");
61 TESTR(r, pthread_cancel(td), "canceling");
62 sem_post(&sem1);
63 TESTR(r, pthread_join(td, &res), "joining canceled thread after blocking sem_wait");
64 TESTC(res == PTHREAD_CANCELED, "canceled thread exit status after blocking sem_wait");
65 TESTC(seqno == 1, "blocking sem_wait");
66
67 /* Cancellation on uncontended sem_timedwait */
68 seqno = 0;
69 sem_post(&sem2);
70 TESTR(r, pthread_create(&td, 0, start_sem_timedwait, 0), "failed to create thread");
71 TESTR(r, pthread_cancel(td), "canceling");
72 sem_post(&sem1);
73 TESTR(r, pthread_join(td, &res), "joining canceled thread after uncontended sem_timedwait");
74 TESTC(res == PTHREAD_CANCELED, "canceled thread exit status after uncontended sem_timedwait");
75 TESTC(seqno == 1, "uncontended sem_timedwait");
76
77 /* Cancellation on blocking sem_timedwait */
78 seqno = 0;
79 sem_trywait(&sem2);
80 TESTR(r, pthread_create(&td, 0, start_sem_timedwait, 0), "failed to create thread");
81 TESTR(r, pthread_cancel(td), "canceling");
82 sem_post(&sem1);
83 TESTR(r, pthread_join(td, &res), "joining canceled thread after blocking sem_timedwait");
84 TESTC(res == PTHREAD_CANCELED, "canceled thread exit status after blocking sem_timedwait");
85 TESTC(seqno == 1, "blocking sem_timedwait");
86
87 return t_status;
88 }
89