1/*	$OpenBSD: switch.c,v 1.7 2022/12/04 23:50:46 cheloha Exp $	*/
2/*
3 * Copyright (c) 1993, 1994, 1995, 1996 by Chris Provenzano and contributors,
4 * proven@mit.edu All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 * 3. All advertising materials mentioning features or use of this software
15 *    must display the following acknowledgement:
16 *	This product includes software developed by Chris Provenzano,
17 *	the University of California, Berkeley, and contributors.
18 * 4. Neither the name of Chris Provenzano, the University, nor the names of
19 *   contributors may be used to endorse or promote products derived
20 *   from this software without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY CHRIS PROVENZANO AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED.  IN NO EVENT SHALL CHRIS PROVENZANO, THE REGENTS OR
26 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
27 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
28 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
29 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
30 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
31 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
32 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33 */
34
35/* ==== test_switch.c ========================================================
36 * Copyright (c) 1993 by Chris Provenzano, proven@athena.mit.edu
37 *
38 * Description : Test context switch functionality.
39 *
40 *  1.00 93/08/04 proven
41 *      -Started coding this file.
42 */
43
44#include <pthread.h>
45#include <stdio.h>
46#include <err.h>
47#include <errno.h>
48#include <unistd.h>
49#include <stdlib.h>
50
51#include "test.h"
52
53const char buf[] = "abcdefghijklmnopqrstuvwxyz";
54char x[sizeof(buf)];
55
56volatile int ending = 0;
57
58/* ==========================================================================
59 * usage();
60 */
61static __dead void
62usage(void)
63{
64	fprintf(stderr, "usage: %s [-c count]\n", getprogname());
65	fprintf(stderr, "count is number of theads, between 2 and 26\n");
66	exit(1);
67}
68
69static void *
70new_thread(void *arg)
71{
72	int i;
73
74	SET_NAME("writer");
75	while (!ending) {
76		CHECKe(write(STDOUT_FILENO, (char *) arg, 1));
77		x[(char *)arg - buf] = 1;
78		for (i = 0; i < 999999; i += 1)
79			;
80	}
81	return NULL;
82}
83
84int
85main(int argc, char *argv[])
86{
87	pthread_t thread;
88	int ch, count = 4;
89	long i;
90	const char *errstr;
91
92	while ((ch = getopt(argc, argv, "c:")) != -1) {
93		switch (ch) {
94		case 'c':
95			count = strtonum(optarg, 2, 26, &errstr);
96			if (errstr != NULL)
97				errx(1, "count is %s: %s", errstr, optarg);
98			break;
99		default:
100			usage();
101		}
102	}
103
104	/* create the threads */
105	for (i = 0; i < count; i++)
106		CHECKr(pthread_create(&thread, NULL, new_thread,
107		    (void*)(buf+i)));
108
109	/* give all threads a chance to run */
110	sleep (2);
111
112	ending = 1;
113	for (i = 0; i < count; i++)
114		ASSERT(x[i]);	/* make sure each thread ran */
115
116	CHECKe(write(STDOUT_FILENO, "\n", 1));
117	SUCCEED;
118}
119