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      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