xref: /minix/tests/kernel/t_lockf.c (revision ebfedea0)
1 /*	$NetBSD: t_lockf.c,v 1.9 2013/10/19 17:45:00 christos Exp $	*/
2 
3 /*-
4  * Copyright (c) 2000 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
17  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
18  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
19  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
20  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26  * POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 #include <atf-c.h>
30 #include <err.h>
31 #include <errno.h>
32 #include <fcntl.h>
33 #include <signal.h>
34 #include <stdio.h>
35 #include <stdlib.h>
36 #include <string.h>
37 #include <unistd.h>
38 
39 #include <sys/types.h>
40 #include <sys/wait.h>
41 #include <sys/ptrace.h>
42 
43 /*
44  * lockf1 regression test:
45  *
46  * Tests:
47  * Fork N child processes, each of which gets M random byte range locks
48  * on a common file.  We ignore all lock errors (practically speaking,
49  * this means EDEADLK or ENOLOCK), but we make numerous passes over all
50  * the children to make sure that they are still awake.  (We do this by
51  * verifying that we can ptrace(ATTACH/DETACH) to the children and get
52  * their status via waitpid().)
53  * When finished, reap all the children.
54  */
55 
56 #define	nlocks		500	/* number of locks per thread */
57 #define	nprocs		10	/* number of processes to spawn */
58 #define	npasses		50	/* number of passes to make over the children */
59 #define	sleeptime	150000	/* sleep time between locks, usec */
60 #define	filesize 	8192	/* size of file to lock */
61 
62 const char *lockfile = "lockf_test";
63 
64 static u_int32_t
65 random_uint32(void)
66 {
67 	return lrand48();
68 }
69 
70 static void
71 trylocks(int id)
72 {
73 	int i, fd;
74 
75 	srand48(getpid());
76 
77 	fd = open (lockfile, O_RDWR, 0);
78 
79 	if (fd < 0)
80 		err(1, "%s", lockfile);
81 
82 	printf("%d: start\n", id);
83 
84 	for (i = 0; i < nlocks; i++) {
85 		struct flock fl;
86 
87 		fl.l_start = random_uint32() % filesize;
88 		fl.l_len = random_uint32() % filesize;
89 		switch (random_uint32() % 3) {
90 		case 0:
91 			fl.l_type = F_RDLCK;
92 			break;
93 		case 1:
94 			fl.l_type = F_WRLCK;
95 			break;
96 		case 2:
97 			fl.l_type = F_UNLCK;
98 			break;
99 		}
100 		fl.l_whence = SEEK_SET;
101 
102 		(void)fcntl(fd, F_SETLKW, &fl);
103 
104 		if (usleep(sleeptime) < 0)
105 		  err(1, "usleep");
106 	}
107 	printf("%d: done\n", id);
108 	close (fd);
109 }
110 
111 ATF_TC(randlock);
112 ATF_TC_HEAD(randlock, tc)
113 {
114 
115 	atf_tc_set_md_var(tc, "timeout", "300");
116 	atf_tc_set_md_var(tc, "descr", "Checks fcntl(2) locking");
117 }
118 
119 ATF_TC_BODY(randlock, tc)
120 {
121 	int i, j, fd;
122 	int pipe_fd[2];
123 	pid_t *pid;
124 	int status;
125 	char pipe_in, pipe_out;
126 	const char pipe_errmsg[] = "child: pipe write failed\n";
127 
128 	(void)unlink(lockfile);
129 
130 	fd = open (lockfile, O_RDWR|O_CREAT|O_EXCL|O_TRUNC, 0666);
131 	ATF_REQUIRE_MSG(fd >= 0, "open(%s): %s", lockfile, strerror(errno));
132 
133 	ATF_REQUIRE_MSG(ftruncate(fd, filesize) >= 0,
134 	    "ftruncate(%s): %s", lockfile, strerror(errno));
135 
136 	ATF_REQUIRE_MSG(pipe(pipe_fd) == 0, "pipe: %s", strerror(errno));
137 
138 	fsync(fd);
139 	close(fd);
140 
141 	pid = malloc(nprocs * sizeof(pid_t));
142 
143 	for (i = 0; i < nprocs; i++) {
144 		pipe_out = (char)('A' + i);
145 		pid[i] = fork();
146 		switch (pid[i]) {
147 		case 0:
148 			if (write(pipe_fd[1], &pipe_out, 1) != 1)
149 				write(STDERR_FILENO, pipe_errmsg,
150 				    __arraycount(pipe_errmsg) - 1);
151 			else
152 				trylocks(i);
153 			_exit(0);
154 			break;
155 		case -1:
156 			atf_tc_fail("fork %d failed", i);
157 			break;
158 		default:
159 			ATF_REQUIRE_MSG(read(pipe_fd[0], &pipe_in, 1) == 1,
160 			    "parent: read_pipe(%i): %s", i, strerror(errno));
161 			ATF_REQUIRE_MSG(pipe_in == pipe_out,
162 			    "parent: pipe does not match");
163 			break;
164 		}
165 	}
166 	for (j = 0; j < npasses; j++) {
167 		printf("parent: run %i\n", j+1);
168 		for (i = 0; i < nprocs; i++) {
169 			ATF_REQUIRE_MSG(ptrace(PT_ATTACH, pid[i], 0, 0) >= 0,
170 			    "ptrace attach %d", pid[i]);
171 			ATF_REQUIRE_MSG(waitpid(pid[i], &status, WUNTRACED) >= 0,
172 			    "waitpid(ptrace)");
173 			usleep(sleeptime / 3);
174 			ATF_REQUIRE_MSG(ptrace(PT_DETACH, pid[i], (caddr_t)1,
175 					       0) >= 0,
176 			    "ptrace detach %d", pid[i]);
177 			usleep(sleeptime / 3);
178 		}
179 	}
180 	for (i = 0; i < nprocs; i++) {
181 		printf("reap %d: ", i);
182 		fflush(stdout);
183 		kill(pid[i], SIGINT);
184 		waitpid(pid[i], &status, 0);
185 		printf(" status %d\n", status);
186 	}
187 	atf_tc_pass();
188 }
189 
190 static int
191 dolock(int fd, int op, off_t lk_off, off_t lk_size)
192 {
193 	off_t result;
194 	int ret;
195 
196 	result = lseek(fd, lk_off, SEEK_SET);
197 	if (result == -1) {
198 		return errno;
199 	}
200 	ATF_REQUIRE_MSG(result == lk_off, "lseek to wrong offset");
201 	ret = lockf(fd, op, lk_size);
202 	if (ret == -1) {
203 		return errno;
204 	}
205 	return 0;
206 }
207 
208 ATF_TC(deadlock);
209 ATF_TC_HEAD(deadlock, tc)
210 {
211 
212 	atf_tc_set_md_var(tc, "timeout", "30");
213 	atf_tc_set_md_var(tc, "descr", "Checks fcntl(2) deadlock detection");
214 }
215 
216 ATF_TC_BODY(deadlock, tc)
217 {
218 	int fd;
219 	int error;
220 	int ret;
221 	pid_t pid;
222 
223 	(void)unlink(lockfile);
224 
225 	fd = open (lockfile, O_RDWR|O_CREAT|O_EXCL|O_TRUNC, 0666);
226 	ATF_REQUIRE_MSG(fd >= 0, "open(%s): %s", lockfile, strerror(errno));
227 
228 	ATF_REQUIRE_MSG(ftruncate(fd, filesize) >= 0,
229 	    "ftruncate(%s): %s", lockfile, strerror(errno));
230 
231 	fsync(fd);
232 
233 	error = dolock(fd, F_LOCK, 0, 1);
234 	ATF_REQUIRE_MSG(error == 0, "initial dolock: %s", strerror(errno));
235 
236 	pid = fork();
237 	ATF_REQUIRE_MSG(pid != -1, "fork failed: %s", strerror(errno));
238 	if (pid == 0) {
239 		error = dolock(fd, F_LOCK, 1, 1);
240 		ATF_REQUIRE_MSG(error == 0, "child dolock: %s",
241 		    strerror(errno));
242 		dolock(fd, F_LOCK, 0, 1);	/* will block */
243 		atf_tc_fail("child did not block");
244 	}
245 	sleep(1);	/* give child time to grab its lock then block */
246 
247 	error = dolock(fd, F_LOCK, 1, 1);
248 	ATF_REQUIRE_MSG(error == EDEADLK, "parent did not detect deadlock: %s",
249 	    strerror(errno));
250 	ret = kill(pid, SIGKILL);
251 	ATF_REQUIRE_MSG(ret != -1, "failed to kill child: %s", strerror(errno));
252 
253 	atf_tc_pass();
254 }
255 
256 ATF_TP_ADD_TCS(tp)
257 {
258 	ATF_TP_ADD_TC(tp, randlock);
259 	ATF_TP_ADD_TC(tp, deadlock);
260 
261 	return atf_no_error();
262 }
263