local.h revision 1.2
1/*
2 * Copyright (c) 2008 Bret S. Lambert <blambert@openbsd.org>
3 *
4 * Permission to use, copy, modify, and distribute this software for any
5 * purpose with or without fee is hereby granted, provided that the above
6 * copyright notice and this permission notice appear in all copies.
7 *
8 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15 */
16
17#include <stdio.h>
18#include <stdlib.h>
19#include <string.h>
20#include <unistd.h>
21#include <pthread.h>
22
23#define THREAD_COUNT 64
24
25#define TEXT	"barnacles"
26#define	TEXT_N	"barnacles\n"
27
28void	run_threads(void (*)(void *), void *);
29
30static pthread_rwlock_t	start;
31static void	(*real_func)(void *);
32
33static void *
34thread(void *arg)
35{
36	int	r;
37
38	if ((r = pthread_rwlock_rdlock(&start)))
39		errx(1, "could not obtain lock in thread: %s", strerror(r));
40	real_func(arg);
41	if ((r = pthread_rwlock_unlock(&start)))
42		errx(1, "could not release lock in thread: %s", strerror(r));
43	return NULL;
44}
45
46void
47run_threads(void (*func)(void *), void *arg)
48{
49	pthread_t	self, pthread[THREAD_COUNT];
50	int	i, r;
51
52	self = pthread_self();
53	real_func = func;
54	if ((r = pthread_rwlock_init(&start, NULL)))
55		errx(1, "could not initialize lock: %s", strerror(r));
56
57	if ((r = pthread_rwlock_wrlock(&start)))		/* block */
58		errx(1, "could not lock lock: %s", strerror(r));
59
60	for (i = 0; i < THREAD_COUNT; i++)
61		if ((r = pthread_create(&pthread[i], NULL, thread, arg))) {
62			warnx("could not create thread: %s", strerror(r));
63			pthread[i] = self;
64		}
65
66
67	if ((r = pthread_rwlock_unlock(&start)))		/* unleash */
68		errx(1, "could not release lock: %s", strerror(r));
69
70	sleep(1);
71
72	if ((r = pthread_rwlock_wrlock(&start)))		/* sync */
73		errx(1, "parent could not sync with children: %s",
74		    strerror(r));
75
76	for (i = 0; i < THREAD_COUNT; i++)
77		if (! pthread_equal(pthread[i], self) &&
78		    (r = pthread_join(pthread[i], NULL)))
79			warnx("could not join thread: %s", strerror(r));
80}
81
82