src/functional/pthread_cancel-points.c

   1 // testing cancellation points
   2 #include <errno.h>
   3 #include <pthread.h>
   4 #include <semaphore.h>
   5 #include <string.h>
   6 #include <sys/mman.h>
   7 #include <fcntl.h>
   8 #include "test.h"
   9
  10 #define TESTC(c, m) ( (c) || (t_error(#c " failed (%s, " m ")\n", cdescr), 0) )
  11 #define TESTR(f, m) do {int r; \
  12         if ((r = (f))) t_error(#f " failed: %s (%s, " m ")\n", strerror(r), cdescr); } while (0)
  13 #define TESTE(f, m) do { \
  14         if ((f)==-1) t_error(#f " failed: %s (%s, " m ")\n", strerror(errno), cdescr); } while (0)
  15
  16 static sem_t sem_seq, sem_test;
  17
  18 static int seqno;
  19
  20 static const char *cdescr = "global initialization";
  21
  22 static void prepare_sem(void *arg)
  23 {
  24         TESTR(sem_init(&sem_test, 0, (long)arg), "creating semaphore");
  25 }
  26
  27 static void cleanup_sem(void *arg)
  28 {
  29         TESTR(sem_destroy(&sem_test), "destroying semaphore");
  30 }
  31
  32 static void execute_sem_wait(void *arg)
  33 {
  34         TESTR(sem_wait(&sem_test), "waiting on semaphore in the canceled thread");
  35 }
  36
  37 static void execute_sem_timedwait(void *arg)
  38 {
  39         struct timespec ts;
  40         clock_gettime(CLOCK_REALTIME, &ts);
  41         ts.tv_sec += 1;
  42         TESTR(sem_timedwait(&sem_test, &ts), "timed-waiting on semaphore in the canceled thread");
  43 }
  44
  45 static pthread_t td_test;
  46
  47 static void *run_test(void *arg)
  48 {
  49         while (sem_wait(&sem_test));
  50         return 0;
  51 }
  52
  53 static void prepare_thread(void *arg)
  54 {
  55         prepare_sem(arg);
  56         TESTR(pthread_create(&td_test, 0, run_test, 0), "creating auxiliary thread");
  57 }
  58
  59 static void cleanup_thread(void *arg)
  60 {
  61         void *res;
  62         if (td_test) {
  63                 TESTR(sem_post(&sem_test), "posting semaphore");
  64                 TESTR(pthread_join(td_test, &res), "joining auxiliary thread");
  65                 TESTC(res == 0, "auxiliary thread exit status");
  66         }
  67         cleanup_sem(arg);
  68 }
  69
  70 static void execute_thread_join(void *arg)
  71 {
  72         TESTR(pthread_join(td_test, 0), "joining in the canceled thread");
  73         td_test = 0;
  74 }
  75
  76 static void prepare_dummy(void *arg)
  77 {
  78 }
  79
  80 static void execute_shm_open(void *arg)
  81 {
  82         int *fd = arg;
  83         TESTE(*fd = shm_open("/testshm", O_RDWR|O_CREAT, 0666), "");
  84 }
  85
  86 static void cleanup_shm(void *arg)
  87 {
  88         int *fd = arg;
  89         if (*fd > 0) {
  90                 TESTE(close(*fd), "shm fd");
  91                 TESTE(shm_unlink("/testshm"), "");
  92         }
  93 }
  94
  95 static struct {
  96         int want_cancel;
  97         void (*prepare)(void *);
  98         void (*execute)(void *);
  99         void (*cleanup)(void *);
 100         void *arg;
 101         const char *descr;
 102 } scenarios[] = {
 103         {1, prepare_sem, execute_sem_wait, cleanup_sem, 0, "blocking sem_wait"},
 104         {1, prepare_sem, execute_sem_wait, cleanup_sem, (void*)1, "non-blocking sem_wait"},
 105         {1, prepare_sem, execute_sem_timedwait, cleanup_sem, 0, "blocking sem_timedwait"},
 106         {1, prepare_sem, execute_sem_timedwait, cleanup_sem, (void*)1, "non-blocking sem_timedwait"},
 107         {1, prepare_thread, execute_thread_join, cleanup_thread, 0, "blocking pthread_join"},
 108         {1, prepare_thread, execute_thread_join, cleanup_thread, (void*)1, "non-blocking pthread_join"},
 109         {0, prepare_dummy, execute_shm_open, cleanup_shm, &(int){0}, "shm_open"},
 110         { 0 }
 111 }, *cur_sc = scenarios;
 112
 113 static void *run_execute(void *arg)
 114 {
 115         pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, 0);
 116         while (sem_wait(&sem_seq));
 117         pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, 0);
 118         seqno = 1;
 119         cur_sc->execute(cur_sc->arg);
 120         seqno = 2;
 121         return 0;
 122 }
 123
 124 int main(void)
 125 {
 126         TESTR(sem_init(&sem_seq, 0, 0), "creating semaphore");
 127
 128         for (; cur_sc->prepare; cur_sc++) {
 129                 pthread_t td;
 130                 void *res;
 131
 132                 cdescr = cur_sc->descr;
 133                 cur_sc->prepare(cur_sc->arg);
 134                 seqno = 0;
 135                 TESTR(pthread_create(&td, 0, run_execute, 0), "creating thread to be canceled");
 136                 TESTR(pthread_cancel(td), "canceling");
 137                 TESTR(sem_post(&sem_seq), "unblocking canceled thread");
 138                 TESTR(pthread_join(td, &res), "joining canceled thread");
 139                 if (cur_sc->want_cancel) {
 140                         TESTC(res == PTHREAD_CANCELED, "canceled thread exit status")
 141                         && TESTC(seqno == 1, "seqno");
 142                 } else {
 143                         TESTC(res != PTHREAD_CANCELED, "canceled thread exit status")
 144                         && TESTC(seqno == 2, "seqno");
 145                 }
 146                 cur_sc->cleanup(cur_sc->arg);
 147         }
 148
 149         return t_status;
 150 }