1 /* $NetBSD: shmtest.c,v 1.2 2001/02/19 22:44:41 cgd Exp $ */ 2 3 /*- 4 * Copyright (c) 1999 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility, 9 * NASA Ames Research Center. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 22 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 23 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 24 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 25 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 26 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 29 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 30 * POSSIBILITY OF SUCH DAMAGE. 31 */ 32 33 /* 34 * Test the SVID-compatible Shared Memory facility. 35 */ 36 37 #include <sys/param.h> 38 #include <sys/ipc.h> 39 #include <sys/shm.h> 40 #include <sys/wait.h> 41 42 #include <err.h> 43 #include <errno.h> 44 #include <signal.h> 45 #include <stdio.h> 46 #include <stdlib.h> 47 #include <string.h> 48 #include <time.h> 49 #include <unistd.h> 50 51 int main(int, char *[]); 52 void print_shmid_ds(struct shmid_ds *, mode_t); 53 void sigsys_handler(int); 54 void sigchld_handler(int); 55 void cleanup(void); 56 void receiver(void); 57 58 const char *m_str = "The quick brown fox jumped over the lazy dog."; 59 60 int sender_shmid = -1; 61 pid_t child_pid; 62 63 key_t shmkey; 64 65 char keyname[] = "/tmp/msgtestXXXXXXXX"; 66 67 int verbose; 68 69 size_t pgsize; 70 71 int 72 main(argc, argv) 73 int argc; 74 char *argv[]; 75 { 76 struct sigaction sa; 77 struct shmid_ds s_ds; 78 sigset_t sigmask; 79 char *shm_buf; 80 int fd, ch; 81 82 if ((fd = mkstemp(keyname)) < 0) 83 err(1, "mkstemp"); 84 85 close(fd); 86 87 while ((ch = getopt(argc, argv, "v")) != -1) { 88 switch (ch) { 89 case 'v': 90 verbose = 1; 91 break; 92 default: 93 fprintf(stderr, "Usage: shmtest [-v]\n"); 94 exit(1); 95 } 96 } 97 98 /* 99 * Install a SIGSYS handler so that we can exit gracefully if 100 * System V Shared Memory support isn't in the kernel. 101 */ 102 sa.sa_handler = sigsys_handler; 103 sigemptyset(&sa.sa_mask); 104 sa.sa_flags = 0; 105 if (sigaction(SIGSYS, &sa, NULL) == -1) 106 err(1, "sigaction SIGSYS"); 107 108 /* 109 * Install and SIGCHLD handler to deal with all possible exit 110 * conditions of the receiver. 111 */ 112 sa.sa_handler = sigchld_handler; 113 sigemptyset(&sa.sa_mask); 114 sa.sa_flags = 0; 115 if (sigaction(SIGCHLD, &sa, NULL) == -1) 116 err(1, "sigaction SIGCHLD"); 117 118 pgsize = sysconf(_SC_PAGESIZE); 119 120 shmkey = ftok(argv[1], 4160); 121 122 /* 123 * Initialize child_pid to ourselves to that the cleanup function 124 * works before we create the receiver. 125 */ 126 child_pid = getpid(); 127 128 /* 129 * Make sure that when the sender exits, the message queue is 130 * removed. 131 */ 132 if (atexit(cleanup) == -1) 133 err(1, "atexit"); 134 135 if ((sender_shmid = shmget(shmkey, pgsize, IPC_CREAT | 0640)) == -1) 136 err(1, "shmget"); 137 138 if (shmctl(sender_shmid, IPC_STAT, &s_ds) == -1) 139 err(1, "shmctl IPC_STAT"); 140 141 if (verbose) 142 print_shmid_ds(&s_ds, 0640); 143 144 s_ds.shm_perm.mode = (s_ds.shm_perm.mode & ~0777) | 0600; 145 146 if (shmctl(sender_shmid, IPC_SET, &s_ds) == -1) 147 err(1, "shmctl IPC_SET"); 148 149 memset(&s_ds, 0, sizeof(s_ds)); 150 151 if (shmctl(sender_shmid, IPC_STAT, &s_ds) == -1) 152 err(1, "shmctl IPC_STAT"); 153 154 if ((s_ds.shm_perm.mode & 0777) != 0600) 155 err(1, "IPC_SET of mode didn't hold"); 156 157 if (verbose) 158 print_shmid_ds(&s_ds, 0600); 159 160 if ((shm_buf = shmat(sender_shmid, NULL, 0)) == (void *) -1) 161 err(1, "sender: shmat"); 162 163 /* 164 * Write the test pattern into the shared memory buffer. 165 */ 166 strlcpy(shm_buf, m_str, pgsize); 167 168 switch ((child_pid = fork())) { 169 case -1: 170 err(1, "fork"); 171 /* NOTREACHED */ 172 173 case 0: 174 receiver(); 175 break; 176 177 default: 178 break; 179 } 180 181 /* 182 * Suspend forever; when we get SIGCHLD, the handler will exit. 183 */ 184 sigemptyset(&sigmask); 185 (void) sigsuspend(&sigmask); 186 187 /* 188 * ...and any other signal is an unexpected error. 189 */ 190 errx(1, "sender: received unexpected signal"); 191 } 192 193 void 194 sigsys_handler(signo) 195 int signo; 196 { 197 198 errx(1, "System V Shared Memory support is not present in the kernel"); 199 } 200 201 void 202 sigchld_handler(signo) 203 int signo; 204 { 205 struct shmid_ds s_ds; 206 int cstatus; 207 208 /* 209 * Reap the child; if it exited successfully, then the test passed! 210 */ 211 if (waitpid(child_pid, &cstatus, 0) != child_pid) 212 err(1, "waitpid"); 213 214 if (WIFEXITED(cstatus) == 0) 215 errx(1, "receiver exited abnormally"); 216 217 if (WEXITSTATUS(cstatus) != 0) 218 errx(1, "receiver exited with status %d", 219 WEXITSTATUS(cstatus)); 220 221 /* 222 * If we get here, the child has exited normally, and thus 223 * we should exit normally too. First, tho, we print out 224 * the final stats for the message queue. 225 */ 226 227 if (shmctl(sender_shmid, IPC_STAT, &s_ds) == -1) 228 err(1, "shmctl IPC_STAT"); 229 230 if (verbose) 231 print_shmid_ds(&s_ds, 0600); 232 233 exit(0); 234 } 235 236 void 237 cleanup() 238 { 239 240 /* 241 * If we're the sender, and it exists, remove the shared memory area. 242 */ 243 if (child_pid != 0 && sender_shmid != -1) { 244 if (shmctl(sender_shmid, IPC_RMID, NULL) == -1) 245 warn("shmctl IPC_RMID"); 246 } 247 248 remove(keyname); 249 } 250 251 void 252 print_shmid_ds(sp, mode) 253 struct shmid_ds *sp; 254 mode_t mode; 255 { 256 uid_t uid = geteuid(); 257 gid_t gid = getegid(); 258 259 printf("PERM: uid %u, gid %u, cuid %u, cgid %u, mode 0%o\n", 260 sp->shm_perm.uid, sp->shm_perm.gid, 261 sp->shm_perm.cuid, sp->shm_perm.cgid, 262 sp->shm_perm.mode & 0777); 263 264 printf("segsz %lu, lpid %d, cpid %d, nattch %u\n", 265 (u_long)sp->shm_segsz, sp->shm_lpid, sp->shm_cpid, 266 sp->shm_nattch); 267 268 printf("atime: %s", ctime(&sp->shm_atime)); 269 printf("dtime: %s", ctime(&sp->shm_dtime)); 270 printf("ctime: %s", ctime(&sp->shm_ctime)); 271 272 /* 273 * Sanity check a few things. 274 */ 275 276 if (sp->shm_perm.uid != uid || sp->shm_perm.cuid != uid) 277 errx(1, "uid mismatch"); 278 279 if (sp->shm_perm.gid != gid || sp->shm_perm.cgid != gid) 280 errx(1, "gid mismatch"); 281 282 if ((sp->shm_perm.mode & 0777) != mode) 283 errx(1, "mode mismatch"); 284 } 285 286 void 287 receiver() 288 { 289 int shmid; 290 void *shm_buf; 291 292 if ((shmid = shmget(shmkey, pgsize, 0)) == -1) 293 err(1, "receiver: shmget"); 294 295 if ((shm_buf = shmat(shmid, NULL, 0)) == (void *) -1) 296 err(1, "receiver: shmat"); 297 298 if (verbose) 299 printf("%s\n", (const char *)shm_buf); 300 if (strcmp((const char *)shm_buf, m_str) != 0) 301 err(1, "receiver: data isn't correct"); 302 303 exit(0); 304 } 305