helgrind/tests/locked_vs_unlocked3.c

   1
   2 /* Needed for older glibcs (2.3 and older, at least) who don't
   3    otherwise "know" about pthread_rwlock_anything or about
   4    PTHREAD_MUTEX_RECURSIVE (amongst things). */
   5 #define _GNU_SOURCE 1
   6
   7 #include <pthread.h>
   8 #include <stdio.h>
   9 #include <stdlib.h>
  10 #include <assert.h>
  11 #include <unistd.h>
  12
  13 /* Test of the mechanism for showing all locks held by a thread.  This
  14    is like locked_vs_unlocked.c, except that it uses a recursively
  15    lockable lock, and one thread holds the lock more than once.  Point
  16    is to check that the lock showing mechanism shows the
  17    lock-number-of-times-held count. */
  18
  19 pthread_mutex_t mx;
  20
  21 int x = 0;
  22
  23 void* child_fn1 ( void* arg )
  24 {
  25    int r;
  26    r= pthread_mutex_lock(&mx);  assert(!r);
  27    r= pthread_mutex_lock(&mx);  assert(!r);
  28    x = 1;
  29    r= pthread_mutex_unlock(&mx);  assert(!r);
  30    r= pthread_mutex_unlock(&mx);  assert(!r);
  31    sleep(1);
  32    return NULL;
  33 }
  34
  35 void* child_fn2 ( void* arg )
  36 {
  37    sleep(1);
  38    x = 1;
  39    return NULL;
  40 }
  41
  42 int main ( int argc, char** argv )
  43 {
  44    int r;
  45    pthread_t child1, child2;
  46    pthread_mutexattr_t attr;
  47    r = pthread_mutexattr_init( &attr );
  48    assert(!r);
  49    r = pthread_mutexattr_settype( &attr, PTHREAD_MUTEX_RECURSIVE );
  50    assert(!r);
  51    r= pthread_mutex_init(&mx, &attr);  assert(!r);
  52
  53    r= pthread_create(&child2, NULL, child_fn2, NULL);  assert(!r);
  54    r= pthread_create(&child1, NULL, child_fn1, NULL);  assert(!r);
  55
  56    r= pthread_join(child1, NULL);  assert(!r);
  57    r= pthread_join(child2, NULL);  assert(!r);
  58
  59    r= pthread_mutex_destroy(&mx);  assert(!r);
  60
  61    return 0;
  62 }