src/regression/pthread_cancel-sem_wait.c

   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
  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
  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
  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
  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 }