sbin/slattach/slattach.c

   1 /*
   2  * Copyright (c) 1988 Regents of the University of California.
   3  * All rights reserved.
   4  *
   5  * This code is derived from software contributed to Berkeley by
   6  * Rick Adams.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  * 3. All advertising materials mentioning features or use of this software
  17  *    must display the following acknowledgement:
  18  *      This product includes software developed by the University of
  19  *      California, Berkeley and its contributors.
  20  * 4. Neither the name of the University nor the names of its contributors
  21  *    may be used to endorse or promote products derived from this software
  22  *    without specific prior written permission.
  23  *
  24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  34  * SUCH DAMAGE.
  35  *
  36  * @(#) Copyright (c) 1988 Regents of the University of California. All rights reserved.
  37  * @(#)slattach.c       4.6 (Berkeley) 6/1/90
  38  * $FreeBSD: src/sbin/slattach/slattach.c,v 1.36 1999/08/28 00:14:25 peter Exp $
  39  * $DragonFly: src/sbin/slattach/slattach.c,v 1.6 2005/02/02 07:59:48 cpressey Exp $
  40  */
  41
  42 #include <sys/types.h>
  43 #include <sys/ioctl.h>
  44 #include <sys/socket.h>
  45
  46 #include <err.h>
  47 #include <fcntl.h>
  48 #include <libutil.h>
  49 #include <paths.h>
  50 #include <signal.h>
  51 #include <stdio.h>
  52 #include <stdlib.h>
  53 #include <strings.h>
  54 #include <syslog.h>
  55 #include <termios.h>
  56 #include <unistd.h>
  57
  58 #include <net/if.h>
  59 #include <net/slip.h>
  60
  61 #define DEFAULT_BAUD    9600
  62
  63 static void sighup_handler(int);        /* SIGHUP handler */
  64 static void sigint_handler(int);        /* SIGINT handler */
  65 static void sigterm_handler(int);       /* SIGTERM handler */
  66 static void sigurg_handler(int);        /* SIGURG handler */
  67 static void exit_handler(int);          /* run exit_cmd iff specified upon exit. */
  68 static void setup_line(int);            /* configure terminal settings */
  69 static void slip_discipline(void);      /* switch to slip line discipline */
  70 static void configure_network(void);    /* configure slip interface */
  71 static void acquire_line(void);         /* get tty device as controlling terminal */
  72 static void usage(void);
  73
  74 int     fd = -1;
  75 char    *dev = (char *)0;       /* path name of the tty (e.g. /dev/tty01) */
  76 char    *dvname;                /* basename of dev */
  77 int     locked = 0;             /* uucp lock active */
  78 int     flow_control = 0;       /* non-zero to enable hardware flow control. */
  79 int     modem_control = HUPCL;  /* !CLOCAL+HUPCL iff we watch carrier. */
  80 int     comstate;               /* TIOCMGET current state of serial driver */
  81 int     redial_on_startup = 0;  /* iff non-zero execute redial_cmd on startup */
  82 speed_t speed = DEFAULT_BAUD;   /* baud rate of tty */
  83 int     slflags = 0;            /* compression flags */
  84 int     unit = -1;              /* slip device unit number */
  85 int     foreground = 0;         /* act as demon if zero, else don't fork. */
  86 int     keepal = 0;             /* keepalive timeout */
  87 int     outfill = 0;            /* outfill timeout */
  88 int     sl_unit = -1;           /* unit number */
  89 int     uucp_lock = 0;          /* do uucp locking */
  90 int     exiting = 0;            /* already running exit_handler */
  91
  92 struct  termios tty;            /* tty configuration/state */
  93
  94 char    tty_path[32];           /* path name of the tty (e.g. /dev/tty01) */
  95 char    pidfilename[40];        /* e.g. /var/run/slattach.tty01.pid */
  96 char    *redial_cmd = 0;        /* command to exec upon shutdown. */
  97 char    *config_cmd = 0;        /* command to exec if slip unit changes. */
  98 char    *exit_cmd = 0;          /* command to exec before exiting. */
  99
 100 static void
 101 usage(void)
 102 {
 103         fprintf(stderr, "%s\n%s\n",
 104 "usage: slattach [-acfhlnz] [-e command] [-r command] [-s speed] [-u command]",
 105 "                [-L] [-K timeout] [-O timeout] [-S unit] device");
 106         /* do not exit here */
 107 }
 108
 109 int
 110 main(int argc, char **argv)
 111 {
 112         int option;
 113
 114         while ((option = getopt(argc, argv, "ace:fhlnr:s:u:zLK:O:S:")) != -1) {
 115                 switch (option) {
 116                 case 'a':
 117                         slflags |= IFF_LINK2;
 118                         slflags &= ~IFF_LINK0;
 119                         break;
 120                 case 'c':
 121                         slflags |= IFF_LINK0;
 122                         slflags &= ~IFF_LINK2;
 123                         break;
 124                 case 'e':
 125                         exit_cmd = (char*) strdup (optarg);
 126                         break;
 127                 case 'f':
 128                         foreground = 1;
 129                         break;
 130                 case 'h':
 131                         flow_control |= CRTSCTS;
 132                         break;
 133                 case 'l':
 134                         modem_control = CLOCAL; /* clear HUPCL too */
 135                         break;
 136                 case 'n':
 137                         slflags |= IFF_LINK1;
 138                         break;
 139                 case 'r':
 140                         redial_cmd = (char*) strdup (optarg);
 141                         break;
 142                 case 's':
 143                         speed = atoi(optarg);
 144                         break;
 145                 case 'u':
 146                         config_cmd = (char*) strdup (optarg);
 147                         break;
 148                 case 'z':
 149                         redial_on_startup = 1;
 150                         break;
 151                 case 'L':
 152                         uucp_lock = 1;
 153                         break;
 154                 case 'K':
 155                         keepal = atoi(optarg);
 156                         break;
 157                 case 'O':
 158                         outfill = atoi(optarg);
 159                         break;
 160                 case 'S':
 161                         sl_unit = atoi(optarg);
 162                         break;
 163                 case '?':
 164                 default:
 165                         usage();
 166                         exit_handler(1);
 167                 }
 168         }
 169
 170         if (optind == argc - 1)
 171                 dev = argv[optind];
 172
 173         if (optind < (argc - 1))
 174             warnx("too many args, first='%s'", argv[optind]);
 175         if (optind > (argc - 1))
 176             warnx("not enough args");
 177         if (dev == (char *)0) {
 178                 usage();
 179                 exit_handler(2);
 180         }
 181         if (strncmp(_PATH_DEV, dev, sizeof(_PATH_DEV) - 1)) {
 182                 strcpy(tty_path, _PATH_DEV);
 183                 strcat(tty_path, "/");
 184                 strncat(tty_path, dev, 10);
 185                 dev = tty_path;
 186         }
 187         dvname = strrchr(dev, '/'); /* always succeeds */
 188         dvname++;                   /* trailing tty pathname component */
 189         snprintf(pidfilename, sizeof(pidfilename),
 190             "%sslattach.%s.pid", _PATH_VARRUN, dvname);
 191         printf("%s\n",pidfilename);
 192
 193         if (!foreground)
 194                 daemon(0,0);    /* fork, setsid, chdir /, and close std*. */
 195         /* daemon() closed stderr, so log errors from here on. */
 196         openlog("slattach",LOG_CONS|LOG_PID,LOG_DAEMON);
 197
 198         acquire_line();         /* get tty device as controlling terminal */
 199         setup_line(0);          /* configure for slip line discipline */
 200         slip_discipline();      /* switch to slip line discipline */
 201
 202         /* upon INT log a timestamp and exit.  */
 203         if (signal(SIGINT,sigint_handler) == SIG_ERR)
 204                 syslog(LOG_NOTICE,"cannot install SIGINT handler: %m");
 205         /* upon TERM log a timestamp and exit.  */
 206         if (signal(SIGTERM,sigterm_handler) == SIG_ERR)
 207                 syslog(LOG_NOTICE,"cannot install SIGTERM handler: %m");
 208         /* upon HUP redial and reconnect.  */
 209         if (signal(SIGHUP,sighup_handler) == SIG_ERR)
 210                 syslog(LOG_NOTICE,"cannot install SIGHUP handler: %m");
 211
 212         if (redial_on_startup)
 213                 sighup_handler(0);
 214         else if (!(modem_control & CLOCAL)) {
 215                 if (ioctl(fd, TIOCMGET, &comstate) < 0)
 216                         syslog(LOG_NOTICE,"cannot get carrier state: %m");
 217                 if (!(comstate & TIOCM_CD)) { /* check for carrier */
 218                         /* force a redial if no carrier */
 219                         kill (getpid(), SIGHUP);
 220                 } else
 221                         configure_network();
 222         } else
 223                 configure_network(); /* configure the network if needed. */
 224
 225         for (;;) {
 226                 sigset_t mask;
 227                 sigemptyset(&mask);
 228                 sigsuspend(&mask);
 229         }
 230 }
 231
 232 /* Close all FDs, fork, reopen tty port as 0-2, and make it the
 233    controlling terminal for our process group. */
 234 static void
 235 acquire_line(void)
 236 {
 237         int ttydisc = TTYDISC;
 238         int oflags;
 239         FILE *pid_file;
 240
 241         /* reset to tty discipline */
 242         if (fd >= 0 && ioctl(fd, TIOCSETD, &ttydisc) < 0) {
 243                 syslog(LOG_ERR, "ioctl(TIOCSETD): %m");
 244                 exit_handler(1);
 245         }
 246
 247         close(STDIN_FILENO); /* close FDs before forking. */
 248         close(STDOUT_FILENO);
 249         close(STDERR_FILENO);
 250         if (fd > 2)
 251                 close(fd);
 252
 253         signal(SIGHUP, SIG_IGN); /* ignore HUP signal when parent dies. */
 254         if (daemon(0,0)) {       /* fork, setsid, chdir /, and close std*. */
 255                 syslog(LOG_ERR, "daemon(0,0): %m");
 256                 exit_handler(1);
 257         }
 258
 259         while (getppid () != 1)
 260                 sleep (1);      /* Wait for parent to die. */
 261
 262         /* create PID file */
 263         if((pid_file = fopen(pidfilename, "w"))) {
 264                 fprintf(pid_file, "%ld\n", (long)getpid());
 265                 fclose(pid_file);
 266         }
 267
 268         if (signal(SIGHUP,sighup_handler) == SIG_ERR) /* Re-enable HUP signal */
 269                 syslog(LOG_NOTICE,"cannot install SIGHUP handler: %m");
 270
 271         if (uucp_lock) {
 272                 /* unlock not needed here, always re-lock with new pid */
 273                 int res;
 274                 if ((res = uu_lock(dvname)) != UU_LOCK_OK) {
 275                         if (res != UU_LOCK_INUSE)
 276                                 syslog(LOG_ERR, "uu_lock: %s", uu_lockerr(res));
 277                         syslog(LOG_ERR, "can't lock %s", dev);
 278                         exit_handler(1);
 279                 }
 280                 locked = 1;
 281         }
 282
 283         if ((fd = open(dev, O_RDWR | O_NONBLOCK, 0)) < 0) {
 284                 syslog(LOG_ERR, "open(%s) %m", dev);
 285                 exit_handler(1);
 286         }
 287         /* Turn off O_NONBLOCK for dumb redialers, if any. */
 288         if ((oflags = fcntl(fd, F_GETFL)) == -1) {
 289                 syslog(LOG_ERR, "fcntl(F_GETFL) failed: %m");
 290                 exit_handler(1);
 291         }
 292         if (fcntl(fd, F_SETFL, oflags & ~O_NONBLOCK) == -1) {
 293                 syslog(LOG_ERR, "fcntl(F_SETFL) failed: %m");
 294                 exit_handler(1);
 295         }
 296         dup2(fd, STDIN_FILENO);
 297         dup2(fd, STDOUT_FILENO);
 298         dup2(fd, STDERR_FILENO);
 299         if (fd > 2)
 300                 close (fd);
 301         fd = STDIN_FILENO;
 302
 303         /* acquire the serial line as a controlling terminal. */
 304         if (ioctl(fd, TIOCSCTTY, 0) < 0) {
 305                 syslog(LOG_ERR,"ioctl(TIOCSCTTY): %m");
 306                 exit_handler(1);
 307         }
 308         /* Make us the foreground process group associated with the
 309            slip line which is our controlling terminal. */
 310         if (tcsetpgrp(fd, getpid()) < 0)
 311                 syslog(LOG_NOTICE,"tcsetpgrp failed: %m");
 312 }
 313
 314 /* Set the tty flags and set DTR. */
 315 /* Call as setup_line(CLOCAL) to force clocal assertion. */
 316 static void
 317 setup_line(int cflag)
 318 {
 319         tty.c_lflag = tty.c_iflag = tty.c_oflag = 0;
 320         tty.c_cflag = CREAD | CS8 | flow_control | modem_control | cflag;
 321         cfsetispeed(&tty, speed);
 322         cfsetospeed(&tty, speed);
 323         /* set the line speed and flow control */
 324         if (tcsetattr(fd, TCSAFLUSH, &tty) < 0) {
 325                 syslog(LOG_ERR, "tcsetattr(TCSAFLUSH): %m");
 326                 exit_handler(1);
 327         }
 328         /* set data terminal ready */
 329         if (ioctl(fd, TIOCSDTR) < 0) {
 330                 syslog(LOG_ERR, "ioctl(TIOCSDTR): %m");
 331                 exit_handler(1);
 332         }
 333 }
 334
 335 /* Put the line in slip discipline. */
 336 static void
 337 slip_discipline(void)
 338 {
 339         struct ifreq ifr;
 340         int slipdisc = SLIPDISC;
 341         int s, tmp_unit = -1;
 342
 343         /* Switch to slip line discipline. */
 344         if (ioctl(fd, TIOCSETD, &slipdisc) < 0) {
 345                 syslog(LOG_ERR, "ioctl(TIOCSETD): %m");
 346                 exit_handler(1);
 347         }
 348
 349         if (sl_unit >= 0 && ioctl(fd, SLIOCSUNIT, &sl_unit) < 0) {
 350                 syslog(LOG_ERR, "ioctl(SLIOCSUNIT): %m");
 351                 exit_handler(1);
 352         }
 353
 354         /* find out what unit number we were assigned */
 355         if (ioctl(fd, SLIOCGUNIT, (caddr_t)&tmp_unit) < 0) {
 356                 syslog(LOG_ERR, "ioctl(SLIOCGUNIT): %m");
 357                 exit_handler(1);
 358         }
 359
 360         if (tmp_unit < 0) {
 361                 syslog(LOG_ERR, "bad unit (%d) from ioctl(SLIOCGUNIT)",tmp_unit);
 362                 exit_handler(1);
 363         }
 364
 365         if (keepal > 0) {
 366                 signal(SIGURG, sigurg_handler);
 367                 if (ioctl(fd, SLIOCSKEEPAL, &keepal) < 0) {
 368                         syslog(LOG_ERR, "ioctl(SLIOCSKEEPAL): %m");
 369                         exit_handler(1);
 370                 }
 371         }
 372         if (outfill > 0 && ioctl(fd, SLIOCSOUTFILL, &outfill) < 0) {
 373                 syslog(LOG_ERR, "ioctl(SLIOCSOUTFILL): %m");
 374                 exit_handler(1);
 375         }
 376
 377         /* open a socket as the handle to the interface */
 378         s = socket(AF_INET, SOCK_DGRAM, 0);
 379         if (s < 0) {
 380                 syslog(LOG_ERR, "socket: %m");
 381                 exit_handler(1);
 382         }
 383         sprintf(ifr.ifr_name, "sl%d", tmp_unit);
 384
 385         /* get the flags for the interface */
 386         if (ioctl(s, SIOCGIFFLAGS, (caddr_t)&ifr) < 0) {
 387                 syslog(LOG_ERR, "ioctl (SIOCGIFFLAGS): %m");
 388                 exit_handler(1);
 389         }
 390
 391         /* Assert any compression or no-icmp flags. */
 392 #define SLMASK (~(IFF_LINK0 | IFF_LINK1 | IFF_LINK2))
 393         ifr.ifr_flags &= SLMASK;
 394         ifr.ifr_flags |= slflags;
 395         if (ioctl(s, SIOCSIFFLAGS, (caddr_t)&ifr) < 0) {
 396                 syslog(LOG_ERR, "ioctl (SIOCSIFFLAGS): %m");
 397                 exit_handler(1);
 398         }
 399         close(s);
 400 }
 401
 402 /* configure the interface, e.g. by passing the unit number to a script. */
 403 static void
 404 configure_network(void)
 405 {
 406         int new_unit;
 407
 408         /* find out what unit number we were assigned */
 409         if (ioctl(fd, SLIOCGUNIT, (caddr_t)&new_unit) < 0) {
 410                 syslog(LOG_ERR, "ioctl(SLIOCGUNIT): %m");
 411                 exit_handler(1);
 412         }
 413         /* iff the unit number changes either invoke config_cmd or punt. */
 414         if (config_cmd) {
 415                 char *s;
 416                 s = (char*) malloc(strlen(config_cmd) + 32);
 417                 if (s == NULL) {
 418                         syslog(LOG_ERR, "malloc failed");
 419                         exit(1);
 420                 }
 421                 sprintf (s, "%s %d %d", config_cmd, unit, new_unit);
 422                 syslog(LOG_NOTICE, "configuring %s (sl%d):", dev, unit);
 423                 syslog(LOG_NOTICE, "  '%s'", s);
 424                 system(s);
 425                 free (s);
 426                 unit = new_unit;
 427         } else {
 428                 /* don't compare unit numbers if this is the first time to attach. */
 429                 if (unit < 0)
 430                         unit = new_unit;
 431                 if (new_unit != unit) {
 432                         syslog(LOG_ERR,
 433         "slip unit changed from sl%d to sl%d, but no -u CMD was specified!",
 434                             unit, new_unit);
 435                         exit_handler(1);
 436                 }
 437                 syslog(LOG_NOTICE,"sl%d connected to %s at %d baud",unit,dev,speed);
 438         }
 439 }
 440
 441 /* sighup_handler() is invoked when carrier drops, eg. before redial. */
 442 static void
 443 sighup_handler(int signo __unused)
 444 {
 445         if(exiting) return;
 446
 447         if (redial_cmd == NULL) {
 448                 syslog(LOG_NOTICE,"SIGHUP on %s (sl%d); exiting", dev, unit);
 449                 exit_handler(1);
 450         }
 451 again:
 452         /* invoke a shell for redial_cmd or punt. */
 453         if (*redial_cmd) { /* Non-empty redial command */
 454                 syslog(LOG_NOTICE,"SIGHUP on %s (sl%d); running '%s'",
 455                        dev, unit, redial_cmd);
 456                 acquire_line(); /* reopen dead line */
 457                 setup_line(CLOCAL);
 458                 if (locked) {
 459                         if (uucp_lock)
 460                                 uu_unlock(dvname);      /* for redial */
 461                         locked = 0;
 462                 }
 463                 if (system(redial_cmd))
 464                         goto again;
 465                 if (uucp_lock) {
 466                         int res;
 467                         if ((res = uu_lock(dvname)) != UU_LOCK_OK) {
 468                                 if (res != UU_LOCK_INUSE)
 469                                         syslog(LOG_ERR, "uu_lock: %s", uu_lockerr(res));
 470                                 syslog(LOG_ERR, "can't relock %s after %s, aborting",
 471                                         dev, redial_cmd);
 472                                 exit_handler(1);
 473                         }
 474                         locked = 1;
 475                 }
 476                 /* Now check again for carrier (dial command is done): */
 477                 if (!(modem_control & CLOCAL)) {
 478                         tty.c_cflag &= ~CLOCAL;
 479                         if (tcsetattr(fd, TCSAFLUSH, &tty) < 0) {
 480                                 syslog(LOG_ERR, "tcsetattr(TCSAFLUSH): %m");
 481                                 exit_handler(1);
 482                         }
 483                         ioctl(fd, TIOCMGET, &comstate);
 484                         if (!(comstate & TIOCM_CD)) { /* check for carrier */
 485                                 /* force a redial if no carrier */
 486                                 goto again;
 487                         }
 488                 } else
 489                         setup_line(0);
 490         } else {        /* Empty redial command */
 491                 syslog(LOG_NOTICE,"SIGHUP on %s (sl%d); reestablish connection",
 492                         dev, unit);
 493                 acquire_line(); /* reopen dead line */
 494                 setup_line(0);  /* restore ospeed from hangup (B0) */
 495                 /* If modem control, just wait for carrier before attaching.
 496                    If no modem control, just fall through immediately. */
 497                 if (!(modem_control & CLOCAL)) {
 498                         int carrier = 0;
 499
 500                         syslog(LOG_NOTICE, "waiting for carrier on %s (sl%d)",
 501                                dev, unit);
 502                         /* Now wait for carrier before attaching line. */
 503                         /* We must poll since CLOCAL prevents signal. */
 504                         while (! carrier) {
 505                                 sleep(2);
 506                                 ioctl(fd, TIOCMGET, &comstate);
 507                                 if (comstate & TIOCM_CD)
 508                                         carrier = 1;
 509                         }
 510                         syslog(LOG_NOTICE, "carrier now present on %s (sl%d)",
 511                                dev, unit);
 512                 }
 513         }
 514         slip_discipline();
 515         configure_network();
 516 }
 517
 518 /* Signal handler for SIGINT.  We just log and exit. */
 519 static void
 520 sigint_handler(int signo __unused)
 521 {
 522         if(exiting) return;
 523         syslog(LOG_NOTICE,"SIGINT on %s (sl%d); exiting",dev,unit);
 524         exit_handler(0);
 525 }
 526
 527 /* Signal handler for SIGURG. */
 528 static void
 529 sigurg_handler(int signo __unused)
 530 {
 531         int ttydisc = TTYDISC;
 532
 533         signal(SIGURG, SIG_IGN);
 534         if(exiting) return;
 535         syslog(LOG_NOTICE,"SIGURG on %s (sl%d); hangup",dev,unit);
 536         if (ioctl(fd, TIOCSETD, &ttydisc) < 0) {
 537                 syslog(LOG_ERR, "ioctl(TIOCSETD): %m");
 538                 exit_handler(1);
 539         }
 540         cfsetospeed(&tty, B0);
 541         if (tcsetattr(fd, TCSANOW, &tty) < 0) {
 542                 syslog(LOG_ERR, "tcsetattr(TCSANOW): %m");
 543                 exit_handler(1);
 544         }
 545         /* Need to go to sighup handler in any case */
 546         if (modem_control & CLOCAL)
 547                 kill (getpid(), SIGHUP);
 548
 549 }
 550
 551 /* Signal handler for SIGTERM.  We just log and exit. */
 552 static void
 553 sigterm_handler(int signo __unused)
 554 {
 555         if(exiting) return;
 556         syslog(LOG_NOTICE,"SIGTERM on %s (sl%d); exiting",dev,unit);
 557         exit_handler(0);
 558 }
 559
 560 /* Run config_cmd if specified before exiting. */
 561 static void
 562 exit_handler(int ret)
 563 {
 564         if(exiting) return;
 565         exiting = 1;
 566         /*
 567          * First close the slip line in case exit_cmd wants it (like to hang
 568          * up a modem or something).
 569          */
 570         if (fd != -1)
 571                 close(fd);
 572         if (uucp_lock && locked)
 573                 uu_unlock(dvname);
 574
 575         /* Remove the PID file */
 576         unlink(pidfilename);
 577
 578         if (config_cmd) {
 579                 char *s;
 580                 s = (char*) malloc(strlen(config_cmd) + 32);
 581                 if (s == NULL) {
 582                         syslog(LOG_ERR, "malloc failed");
 583                         exit(1);
 584                 }
 585                 sprintf (s, "%s %d -1", config_cmd, unit);
 586                 syslog(LOG_NOTICE, "deconfiguring %s (sl%d):", dev, unit);
 587                 syslog(LOG_NOTICE, "  '%s'", s);
 588                 system(s);
 589                 free (s);
 590         }
 591         /* invoke a shell for exit_cmd. */
 592         if (exit_cmd) {
 593                 syslog(LOG_NOTICE,"exiting after running %s", exit_cmd);
 594                 system(exit_cmd);
 595         }
 596         exit(ret);
 597 }
 598
 599 /* local variables: */
 600 /* c-indent-level: 8 */
 601 /* c-argdecl-indent: 0 */
 602 /* c-label-offset: -8 */
 603 /* c-continued-statement-offset: 8 */
 604 /* c-brace-offset: 0 */
 605 /* comment-column: 32 */
 606 /* end: */