1
2/* Check that an error is reported for various kinds of bogus
3   pthread_mutex_unlock calls. */
4
5#include <pthread.h>
6#include <stdio.h>
7#include <stdlib.h>
8
9void* child_fn ( void* arg )
10{
11   pthread_mutex_unlock( (pthread_mutex_t*)arg ); /* ERROR */
12   return NULL;
13}
14
15void nearly_main ( void )
16{
17   pthread_t child;
18   pthread_mutex_t mx1, mx2;
19   int bogus[100], i;
20   /* fill bogus with values which will cause glibc's pth_mx_unlock to fail */
21   for (i = 0; i < 100; i++) bogus[i] = 0xFFFFFFFF;
22   /* Unlocking a lock that is already unlocked */
23   pthread_mutex_init( &mx1, NULL );
24   pthread_mutex_lock( &mx1 );
25   pthread_mutex_unlock( &mx1 );
26
27   pthread_mutex_unlock( &mx1 ); /* ERROR */
28
29   /* Unlocking a lock that is held by a different thread */
30
31   pthread_mutex_init( &mx2, NULL );
32   pthread_mutex_lock( &mx2 );
33   // start child and get it to unlock this lock
34
35   pthread_create( &child, NULL, child_fn, (void*)&mx2 );
36      /* child runs and attempts to unlock our lock.  Error
37         is reported in child_fn. */
38   pthread_join(child, NULL );
39
40   /* Unlocking a totally bogus lock. */
41   pthread_mutex_unlock( (pthread_mutex_t*) &bogus[50] ); /* ERROR */
42
43   /* Now we get a freeing-locked-lock error, since the stack
44      frame is removed whilst mx2 is still locked. */
45}
46
47int main ( void )
48{
49   nearly_main(); fprintf(stderr, "---------------------\n" );
50   nearly_main();
51   return 0;
52}
53