1/** Initialize several kinds of mutexes and lock each mutex twice.
2 *  Note: locking a regular mutex twice causes a deadlock.
3 */
4
5#define _GNU_SOURCE
6
7#include <stdio.h>
8#include <unistd.h>
9#include <pthread.h>
10#include "../../config.h"
11
12
13static void lock_twice(pthread_mutex_t* const p)
14{
15  if (pthread_mutex_trylock(p) != 0)
16    fprintf(stderr, "first lock call failed !\n");
17  if (pthread_mutex_trylock(p) != 0)
18    fprintf(stderr, "second lock call failed !\n");
19  if (pthread_mutex_unlock(p) != 0)
20    fprintf(stderr, "first unlock call failed !\n");
21  if (pthread_mutex_unlock(p) != 0)
22    fprintf(stderr, "second unlock call failed !\n");
23}
24
25int main(int argc, char** argv)
26{
27#if defined(HAVE_PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP)
28  {
29    pthread_mutex_t m = PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP;
30
31    fprintf(stderr, "Recursive mutex (statically initialized).\n");
32    lock_twice(&m);
33    pthread_mutex_destroy(&m);
34  }
35#endif
36#if defined(HAVE_PTHREAD_MUTEX_RECURSIVE_NP)
37  {
38    pthread_mutex_t m;
39    pthread_mutexattr_t attr;
40
41    fprintf(stderr, "\nRecursive mutex (initialized via mutex attributes).\n");
42    pthread_mutexattr_init(&attr);
43    pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE_NP);
44    pthread_mutex_init(&m, &attr);
45    pthread_mutexattr_destroy(&attr);
46    lock_twice(&m);
47    pthread_mutex_destroy(&m);
48  }
49#endif
50#if defined(HAVE_PTHREAD_MUTEX_ERRORCHECK_NP)
51  {
52    pthread_mutex_t m;
53    pthread_mutexattr_t attr;
54
55    fprintf(stderr, "\nError checking mutex.\n");
56    pthread_mutexattr_init(&attr);
57    pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_ERRORCHECK_NP);
58    pthread_mutex_init(&m, &attr);
59    pthread_mutexattr_destroy(&attr);
60    lock_twice(&m);
61    pthread_mutex_destroy(&m);
62  }
63#endif
64
65  {
66    pthread_mutex_t m = PTHREAD_MUTEX_INITIALIZER;
67
68    fprintf(stderr, "\nNon-recursive mutex.\n");
69    lock_twice(&m);
70  }
71
72  fprintf(stderr, "\nDone.\n");
73
74  return 0;
75}
76