1 /* Copyright (C) 2002-2022 Free Software Foundation, Inc.
2    This file is part of the GNU C Library.
3 
4    The GNU C Library is free software; you can redistribute it and/or
5    modify it under the terms of the GNU Lesser General Public
6    License as published by the Free Software Foundation; either
7    version 2.1 of the License, or (at your option) any later version.
8 
9    The GNU C Library is distributed in the hope that it will be useful,
10    but WITHOUT ANY WARRANTY; without even the implied warranty of
11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
12    Lesser General Public License for more details.
13 
14    You should have received a copy of the GNU Lesser General Public
15    License along with the GNU C Library; if not, see
16    <https://www.gnu.org/licenses/>.  */
17 
18 #include <pthread.h>
19 #include <stdio.h>
20 #include <stdlib.h>
21 #include <string.h>
22 #include <unistd.h>
23 
24 static int do_test (void);
25 
26 #define TEST_FUNCTION do_test ()
27 #include "../test-skeleton.c"
28 
29 /* Note that this test requires more than the standard.  It is
30    required that there are no spurious wakeups if only more readers
31    are added.  This is a reasonable demand.  */
32 
33 
34 static pthread_cond_t cond = PTHREAD_COND_INITIALIZER;
35 static pthread_mutex_t mut = PTHREAD_MUTEX_INITIALIZER;
36 
37 
38 #define N 10
39 
40 
41 static void *
tf(void * arg)42 tf (void *arg)
43 {
44   int i = (long int) arg;
45   int err;
46 
47   /* Get the mutex.  */
48   err = pthread_mutex_lock (&mut);
49   if (err != 0)
50     {
51       printf ("child %d mutex_lock failed: %s\n", i, strerror (err));
52       exit (1);
53     }
54 
55   /* This call should never return.  */
56   xpthread_cond_wait (&cond, &mut);
57   puts ("error: pthread_cond_wait in tf returned");
58 
59   /* We should never get here.  */
60   exit (1);
61 
62   return NULL;
63 }
64 
65 
66 static int
do_test(void)67 do_test (void)
68 {
69   int err;
70   int i;
71 
72   for (i = 0; i < N; ++i)
73     {
74       pthread_t th;
75 
76       if (i != 0)
77 	{
78 	  /* Release the mutex.  */
79 	  err = pthread_mutex_unlock (&mut);
80 	  if (err != 0)
81 	    {
82 	      printf ("mutex_unlock %d failed: %s\n", i, strerror (err));
83 	      return 1;
84 	    }
85 	}
86 
87       err = pthread_create (&th, NULL, tf, (void *) (long int) i);
88       if (err != 0)
89 	{
90 	  printf ("create %d failed: %s\n", i, strerror (err));
91 	  return 1;
92 	}
93 
94       /* Get the mutex.  */
95       err = pthread_mutex_lock (&mut);
96       if (err != 0)
97 	{
98 	  printf ("mutex_lock %d failed: %s\n", i, strerror (err));
99 	  return 1;
100 	}
101     }
102 
103   delayed_exit (1);
104 
105   /* This call should never return.  */
106   xpthread_cond_wait (&cond, &mut);
107 
108   puts ("error: pthread_cond_wait in do_test returned");
109   return 1;
110 }
111