1 /*	$OpenBSD: blocked_shutdown.c,v 1.2 2012/02/20 17:06:11 kurt Exp $	*/
2 /*
3  * Copyright (c) 2006 Kurt Miller <kurt@intricatesoftware.com>
4  *
5  * Permission to use, copy, modify, and distribute this software for any
6  * purpose with or without fee is hereby granted, provided that the above
7  * copyright notice and this permission notice appear in all copies.
8  *
9  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16  */
17 
18 /*
19  * Test shutdown() racing with other threads using the same file
20  * descriptor, with some of them blocking on data that will never
21  * arrive.
22  */
23 
24 #include <pthread.h>
25 #include <unistd.h>
26 #include <fcntl.h>
27 #include <time.h>
28 #include <sys/types.h>
29 #include <sys/socket.h>
30 #include <netinet/in.h>
31 #include "test.h"
32 
33 #define ITERATIONS	100
34 #define WAITING_THREADS	5
35 
36 static void *
37 deadlock_detector(void *arg)
38 {
39 	sleep(15);
40 	PANIC("deadlock detected");
41 }
42 
43 static void *
44 waiting_read(void *arg)
45 {
46 	int fd = *(int *)arg;
47 	struct sockaddr remote_addr;
48 	char readBuf;
49 	int n, remote_addr_len = sizeof(struct sockaddr);
50 
51 	n = recvfrom(fd, &readBuf, 1, 0, &remote_addr, &remote_addr_len);
52 
53 	if (n == -1)
54 		return ((caddr_t)NULL + errno);
55 	else
56 		return (NULL);
57 }
58 
59 int
60 main(int argc, char *argv[])
61 {
62 	pthread_t waiting_threads[WAITING_THREADS];
63 	pthread_t deadlock_thread;
64 	struct sockaddr_in addr;
65 	int fd, i, j;
66 	void *value_ptr;
67 	struct timespec rqtp;
68 
69 	rqtp.tv_sec = 0;
70 	rqtp.tv_nsec = 1000000;
71 
72 	bzero((char *) &addr, sizeof addr);
73 	addr.sin_family = AF_INET;
74 	addr.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
75 
76 	CHECKr(pthread_create(&deadlock_thread, NULL,
77 	    deadlock_detector, NULL));
78 
79 	for (i = 0; i < ITERATIONS; i++) {
80 		CHECKe(fd = socket(AF_INET, SOCK_DGRAM, 0));
81 		addr.sin_port = htons(0);
82  		CHECKr(bind(fd, (struct sockaddr *)&addr, sizeof(addr)));
83 		for (j = 0; j < WAITING_THREADS; j++)
84 			CHECKr(pthread_create(&waiting_threads[j], NULL,
85 			    waiting_read, (void *)&fd));
86 		nanosleep(&rqtp, NULL);
87 		CHECKr(shutdown(fd, SHUT_RDWR));
88 		for (j = 0; j < WAITING_THREADS; j++) {
89 			CHECKr(pthread_join(waiting_threads[j], &value_ptr));
90 			ASSERT(value_ptr == NULL);
91 		}
92 		CHECKr(close(fd));
93 	}
94 	SUCCEED;
95 }
96