xref: /netbsd-src/external/gpl3/gdb.old/dist/gdb/testsuite/gdb.threads/watchthreads.c (revision bdc22b2e01993381dcefeff2bc9b56ca75a4235c)
1 /* This testcase is part of GDB, the GNU debugger.
2 
3    Copyright 2002-2016 Free Software Foundation, Inc.
4 
5    This program is free software; you can redistribute it and/or modify
6    it under the terms of the GNU General Public License as published by
7    the Free Software Foundation; either version 3 of the License, or
8    (at your option) any later version.
9 
10    This program is distributed in the hope that it will be useful,
11    but WITHOUT ANY WARRANTY; without even the implied warranty of
12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13    GNU General Public License for more details.
14 
15    You should have received a copy of the GNU General Public License
16    along with this program.  If not, see <http://www.gnu.org/licenses/>.
17 
18    This file is copied from schedlock.c.  */
19 
20 #include <stdio.h>
21 #include <unistd.h>
22 #include <stdlib.h>
23 #include <pthread.h>
24 
25 void *thread_function (void *arg); /* Function executed by each thread.  */
26 
27 #define NUM 5
28 
29 unsigned int args[NUM+1];
30 
31 int
32 main ()
33 {
34     int res;
35     pthread_t threads[NUM];
36     void *thread_result;
37     long i;
38 
39     /* To keep the test determinative, initialize args first,
40        then start all the threads.  Otherwise, the way watchthreads.exp
41        is written, we have to worry about things like threads[0] getting
42        to 29 hits of args[0] before args[1] gets changed.  */
43 
44     for (i = 0; i < NUM; i++)
45       {
46 	/* The call to usleep is so that when the watchpoint triggers,
47 	   the pc is still on the same line.  */
48 	args[i] = 1; usleep (1); /* Init value.  */
49       }
50 
51     for (i = 0; i < NUM; i++)
52       {
53 	res = pthread_create (&threads[i],
54 			      NULL,
55 			      thread_function,
56 			      (void *) i);
57       }
58 
59     args[i] = 1;
60     thread_function ((void *) i);
61 
62     exit (EXIT_SUCCESS);
63 }
64 
65 void *
66 thread_function (void *arg)
67 {
68     int my_number =  (long) arg;
69     int *myp = (int *) &args[my_number];
70 
71     /* Don't run forever.  Run just short of it :)  */
72     while (*myp > 0)
73       {
74 	(*myp) ++; usleep (1);  /* Loop increment.  */
75       }
76 
77     pthread_exit (NULL);
78 }
79 
80