xref: /netbsd-src/tests/kernel/t_lockf.c (revision 6de51c519f1b899da63c1bf576f478920b89083f)
1 /*	$NetBSD: t_lockf.c,v 1.6 2013/02/19 04:58:40 pgoyette 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, ret, 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 		ret = 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 
127 	(void)unlink(lockfile);
128 
129 	fd = open (lockfile, O_RDWR|O_CREAT|O_EXCL|O_TRUNC, 0666);
130 	ATF_REQUIRE_MSG(fd >= 0, "open(%s): %s", lockfile, strerror(errno));
131 
132 	ATF_REQUIRE_MSG(ftruncate(fd, filesize) >= 0,
133 	    "ftruncate(%s): %s", lockfile, strerror(errno));
134 
135 	ATF_REQUIRE_MSG(pipe(pipe_fd) == 0, "pipe: %s", strerror(errno));
136 
137 	fsync(fd);
138 	close(fd);
139 
140 	pid = malloc(nprocs * sizeof(pid_t));
141 
142 	for (i = 0; i < nprocs; i++) {
143 		pipe_out = (char)('A' + i);
144 		pid[i] = fork();
145 		switch (pid[i]) {
146 		case 0:
147 			if (write(pipe_fd[1], &pipe_out, 1) != 1)
148 				printf("write_pipe(%i): %s", i,
149 				strerror(errno));
150 			else
151 				trylocks(i);
152 			_exit(0);
153 			break;
154 		case -1:
155 			atf_tc_fail("fork %d failed", i);
156 			break;
157 		default:
158 			ATF_REQUIRE_MSG(read(pipe_fd[0], &pipe_in, 1) == 1,
159 			    "parent: read_pipe(%i): %s", i, strerror(errno));
160 			ATF_REQUIRE_MSG(pipe_in == pipe_out,
161 			    "parent: pipe does not match");
162 			break;
163 		}
164 	}
165 	for (j = 0; j < npasses; j++) {
166 		printf("parent: run %i\n", j+1);
167 		for (i = 0; i < nprocs; i++) {
168 			ATF_REQUIRE_MSG(ptrace(PT_ATTACH, pid[i], 0, 0) >= 0,
169 			    "ptrace attach %d", pid[i]);
170 			ATF_REQUIRE_MSG(waitpid(pid[i], &status, WUNTRACED) >= 0,
171 			    "waitpid(ptrace)");
172 			usleep(sleeptime / 3);
173 			ATF_REQUIRE_MSG(ptrace(PT_DETACH, pid[i], (caddr_t)1,
174 					       0) >= 0,
175 			    "ptrace detach %d", pid[i]);
176 			usleep(sleeptime / 3);
177 		}
178 	}
179 	for (i = 0; i < nprocs; i++) {
180 		printf("reap %d: ", i);
181 		fflush(stdout);
182 		kill(pid[i], SIGINT);
183 		waitpid(pid[i], &status, 0);
184 		printf(" status %d\n", status);
185 	}
186 	atf_tc_pass();
187 }
188 
189 static int
190 dolock(int fd, int op, off_t lk_off, off_t lk_size)
191 {
192 	off_t result;
193 	int ret;
194 
195 	result = lseek(fd, lk_off, SEEK_SET);
196 	if (result == -1) {
197 		return errno;
198 	}
199 	ATF_REQUIRE_MSG(result == lk_off, "lseek to wrong offset");
200 	ret = lockf(fd, op, lk_size);
201 	if (ret == -1) {
202 		return errno;
203 	}
204 	return 0;
205 }
206 
207 ATF_TC(deadlock);
208 ATF_TC_HEAD(deadlock, tc)
209 {
210 
211 	atf_tc_set_md_var(tc, "timeout", "30");
212 	atf_tc_set_md_var(tc, "descr", "Checks fcntl(2) deadlock detection");
213 }
214 
215 ATF_TC_BODY(deadlock, tc)
216 {
217 	int fd;
218 	int error;
219 	int ret;
220 	pid_t pid;
221 
222 	(void)unlink(lockfile);
223 
224 	fd = open (lockfile, O_RDWR|O_CREAT|O_EXCL|O_TRUNC, 0666);
225 	ATF_REQUIRE_MSG(fd >= 0, "open(%s): %s", lockfile, strerror(errno));
226 
227 	ATF_REQUIRE_MSG(ftruncate(fd, filesize) >= 0,
228 	    "ftruncate(%s): %s", lockfile, strerror(errno));
229 
230 	fsync(fd);
231 
232 	error = dolock(fd, F_LOCK, 0, 1);
233 	ATF_REQUIRE_MSG(error == 0, "initial dolock: %s", strerror(errno));
234 
235 	pid = fork();
236 	ATF_REQUIRE_MSG(pid != -1, "fork failed: %s", strerror(errno));
237 	if (pid == 0) {
238 		error = dolock(fd, F_LOCK, 1, 1);
239 		ATF_REQUIRE_MSG(error == 0, "child dolock: %s",
240 		    strerror(errno));
241 		dolock(fd, F_LOCK, 0, 1);	/* will block */
242 		atf_tc_fail("child did not block");
243 	}
244 	sleep(1);	/* give child time to grab its lock then block */
245 
246 	error = dolock(fd, F_LOCK, 1, 1);
247 	ATF_REQUIRE_MSG(error == EDEADLK, "parent did not detect deadlock: %s",
248 	    strerror(errno));
249 	ret = kill(pid, SIGKILL);
250 	ATF_REQUIRE_MSG(ret != -1, "failed to kill child: %s", strerror(errno));
251 
252 	atf_tc_pass();
253 }
254 
255 ATF_TP_ADD_TCS(tp)
256 {
257 	ATF_TP_ADD_TC(tp, randlock);
258 	ATF_TP_ADD_TC(tp, deadlock);
259 
260 	return atf_no_error();
261 }
262