regress/sys/kern/sysvshm/shmtest.c

   1 /*      $NetBSD: shmtest.c,v 1.4 2005/02/06 06:05:20 perry 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 void    usage(void);
  58
  59 const char *m_str = "The quick brown fox jumped over the lazy dog.";
  60
  61 int     sender_shmid = -1;
  62 pid_t   child_pid;
  63
  64 key_t   shmkey;
  65
  66 size_t  pgsize;
  67
  68 int
  69 main(argc, argv)
  70         int argc;
  71         char *argv[];
  72 {
  73         struct sigaction sa;
  74         struct shmid_ds s_ds;
  75         sigset_t sigmask;
  76         char *shm_buf;
  77
  78         if (argc != 2)
  79                 usage();
  80
  81         /*
  82          * Install a SIGSYS handler so that we can exit gracefully if
  83          * System V Shared Memory support isn't in the kernel.
  84          */
  85         sa.sa_handler = sigsys_handler;
  86         sigemptyset(&sa.sa_mask);
  87         sa.sa_flags = 0;
  88         if (sigaction(SIGSYS, &sa, NULL) == -1)
  89                 err(1, "sigaction SIGSYS");
  90
  91         /*
  92          * Install and SIGCHLD handler to deal with all possible exit
  93          * conditions of the receiver.
  94          */
  95         sa.sa_handler = sigchld_handler;
  96         sigemptyset(&sa.sa_mask);
  97         sa.sa_flags = 0;
  98         if (sigaction(SIGCHLD, &sa, NULL) == -1)
  99                 err(1, "sigaction SIGCHLD");
 100
 101         pgsize = sysconf(_SC_PAGESIZE);
 102
 103         shmkey = ftok(argv[1], 4160);
 104
 105         /*
 106          * Initialize child_pid to ourselves to that the cleanup function
 107          * works before we create the receiver.
 108          */
 109         child_pid = getpid();
 110
 111         /*
 112          * Make sure that when the sender exits, the message queue is
 113          * removed.
 114          */
 115         if (atexit(cleanup) == -1)
 116                 err(1, "atexit");
 117
 118         if ((sender_shmid = shmget(shmkey, pgsize, IPC_CREAT | 0640)) == -1)
 119                 err(1, "shmget");
 120
 121         if (shmctl(sender_shmid, IPC_STAT, &s_ds) == -1)
 122                 err(1, "shmctl IPC_STAT");
 123
 124         print_shmid_ds(&s_ds, 0640);
 125
 126         s_ds.shm_perm.mode = (s_ds.shm_perm.mode & ~0777) | 0600;
 127
 128         if (shmctl(sender_shmid, IPC_SET, &s_ds) == -1)
 129                 err(1, "shmctl IPC_SET");
 130
 131         memset(&s_ds, 0, sizeof(s_ds));
 132
 133         if (shmctl(sender_shmid, IPC_STAT, &s_ds) == -1)
 134                 err(1, "shmctl IPC_STAT");
 135
 136         if ((s_ds.shm_perm.mode & 0777) != 0600)
 137                 err(1, "IPC_SET of mode didn't hold");
 138
 139         print_shmid_ds(&s_ds, 0600);
 140
 141         if ((shm_buf = shmat(sender_shmid, NULL, 0)) == (void *) -1)
 142                 err(1, "sender: shmat");
 143
 144         /*
 145          * Write the test pattern into the shared memory buffer.
 146          */
 147         strcpy(shm_buf, m_str);
 148
 149         switch ((child_pid = fork())) {
 150         case -1:
 151                 err(1, "fork");
 152                 /* NOTREACHED */
 153
 154         case 0:
 155                 receiver();
 156                 break;
 157
 158         default:
 159                 break;
 160         }
 161
 162         /*
 163          * Suspend forever; when we get SIGCHLD, the handler will exit.
 164          */
 165         sigemptyset(&sigmask);
 166         (void) sigsuspend(&sigmask);
 167
 168         /*
 169          * ...and any other signal is an unexpected error.
 170          */
 171         errx(1, "sender: received unexpected signal");
 172 }
 173
 174 void
 175 sigsys_handler(signo)
 176         int signo;
 177 {
 178
 179         errx(1, "System V Shared Memory support is not present in the kernel");
 180 }
 181
 182 void
 183 sigchld_handler(signo)
 184         int signo;
 185 {
 186         struct shmid_ds s_ds;
 187         int cstatus;
 188
 189         /*
 190          * Reap the child; if it exited successfully, then the test passed!
 191          */
 192         if (waitpid(child_pid, &cstatus, 0) != child_pid)
 193                 err(1, "waitpid");
 194
 195         if (WIFEXITED(cstatus) == 0)
 196                 errx(1, "receiver exited abnormally");
 197
 198         if (WEXITSTATUS(cstatus) != 0)
 199                 errx(1, "receiver exited with status %d",
 200                     WEXITSTATUS(cstatus));
 201
 202         /*
 203          * If we get here, the child has exited normally, and thus
 204          * we should exit normally too.  First, tho, we print out
 205          * the final stats for the message queue.
 206          */
 207
 208         if (shmctl(sender_shmid, IPC_STAT, &s_ds) == -1)
 209                 err(1, "shmctl IPC_STAT");
 210
 211         print_shmid_ds(&s_ds, 0600);
 212
 213         exit(0);
 214 }
 215
 216 void
 217 cleanup()
 218 {
 219
 220         /*
 221          * If we're the sender, and it exists, remove the shared memory area.
 222          */
 223         if (child_pid != 0 && sender_shmid != -1) {
 224                 if (shmctl(sender_shmid, IPC_RMID, NULL) == -1)
 225                         warn("shmctl IPC_RMID");
 226         }
 227 }
 228
 229 void
 230 print_shmid_ds(sp, mode)
 231         struct shmid_ds *sp;
 232         mode_t mode;
 233 {
 234         uid_t uid = geteuid();
 235         gid_t gid = getegid();
 236
 237         printf("PERM: uid %d, gid %d, cuid %d, cgid %d, mode 0%o\n",
 238             sp->shm_perm.uid, sp->shm_perm.gid,
 239             sp->shm_perm.cuid, sp->shm_perm.cgid,
 240             sp->shm_perm.mode & 0777);
 241
 242         printf("segsz %lu, lpid %d, cpid %d, nattch %u\n",
 243             (u_long)sp->shm_segsz, sp->shm_lpid, sp->shm_cpid,
 244             sp->shm_nattch);
 245
 246         printf("atime: %s", ctime(&sp->shm_atime));
 247         printf("dtime: %s", ctime(&sp->shm_dtime));
 248         printf("ctime: %s", ctime(&sp->shm_ctime));
 249
 250         /*
 251          * Sanity check a few things.
 252          */
 253
 254         if (sp->shm_perm.uid != uid || sp->shm_perm.cuid != uid)
 255                 errx(1, "uid mismatch");
 256
 257         if (sp->shm_perm.gid != gid || sp->shm_perm.cgid != gid)
 258                 errx(1, "gid mismatch");
 259
 260         if ((sp->shm_perm.mode & 0777) != mode)
 261                 errx(1, "mode mismatch");
 262 }
 263
 264 void
 265 usage()
 266 {
 267
 268         fprintf(stderr, "usage: %s keypath\n", getprogname());
 269         exit(1);
 270 }
 271
 272 void
 273 receiver()
 274 {
 275         int shmid;
 276         void *shm_buf;
 277
 278         if ((shmid = shmget(shmkey, pgsize, 0)) == -1)
 279                 err(1, "receiver: shmget");
 280
 281         if ((shm_buf = shmat(shmid, NULL, 0)) == (void *) -1)
 282                 err(1, "receiver: shmat");
 283
 284         printf("%s\n", (const char *)shm_buf);
 285         if (strcmp((const char *)shm_buf, m_str) != 0)
 286                 err(1, "receiver: data isn't correct");
 287
 288         exit(0);
 289 }