usr.bin/pkill/pkill.c

   1 /*      $NetBSD: pkill.c,v 1.16 2005/10/10 22:13:20 kleink Exp $        */
   2
   3 /*-
   4  * Copyright (c) 2002 The NetBSD Foundation, Inc.
   5  * Copyright (c) 2005 Pawel Jakub Dawidek <pjd@FreeBSD.org>
   6  * All rights reserved.
   7  *
   8  * This code is derived from software contributed to The NetBSD Foundation
   9  * by Andrew Doran.
  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  * 3. All advertising materials mentioning features or use of this software
  20  *    must display the following acknowledgement:
  21  *      This product includes software developed by the NetBSD
  22  *      Foundation, Inc. and its contributors.
  23  * 4. Neither the name of The NetBSD Foundation nor the names of its
  24  *    contributors may be used to endorse or promote products derived
  25  *    from this software without specific prior written permission.
  26  *
  27  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
  28  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  29  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  30  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
  31  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  32  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  33  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  34  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  35  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  36  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  37  * POSSIBILITY OF SUCH DAMAGE.
  38  */
  39
  40 #include <sys/cdefs.h>
  41 __FBSDID("$FreeBSD$");
  42
  43 #include <sys/types.h>
  44 #include <sys/param.h>
  45 #include <sys/sysctl.h>
  46 #include <sys/proc.h>
  47 #include <sys/queue.h>
  48 #include <sys/stat.h>
  49 #include <sys/time.h>
  50 #include <sys/user.h>
  51
  52 #include <stdio.h>
  53 #include <stdlib.h>
  54 #include <limits.h>
  55 #include <paths.h>
  56 #include <string.h>
  57 #include <unistd.h>
  58 #include <signal.h>
  59 #include <regex.h>
  60 #include <ctype.h>
  61 #include <fcntl.h>
  62 #include <kvm.h>
  63 #include <err.h>
  64 #include <pwd.h>
  65 #include <grp.h>
  66 #include <errno.h>
  67 #include <locale.h>
  68
  69 #define STATUS_MATCH    0
  70 #define STATUS_NOMATCH  1
  71 #define STATUS_BADUSAGE 2
  72 #define STATUS_ERROR    3
  73
  74 #define MIN_PID 5
  75 #define MAX_PID 99999
  76
  77 /* Ignore system-processes (if '-S' flag is not specified) and myself. */
  78 #define PSKIP(kp)       ((kp)->ki_pid == mypid ||                       \
  79                          (!kthreads && ((kp)->ki_flag & P_KTHREAD) != 0))
  80
  81 enum listtype {
  82         LT_GENERIC,
  83         LT_USER,
  84         LT_GROUP,
  85         LT_TTY,
  86         LT_PGRP,
  87         LT_JID,
  88         LT_SID
  89 };
  90
  91 struct list {
  92         SLIST_ENTRY(list) li_chain;
  93         long    li_number;
  94 };
  95
  96 SLIST_HEAD(listhead, list);
  97
  98 static struct kinfo_proc *plist;
  99 static char     *selected;
 100 static const char *delim = "\n";
 101 static int      nproc;
 102 static int      pgrep;
 103 static int      signum = SIGTERM;
 104 static int      newest;
 105 static int      oldest;
 106 static int      interactive;
 107 static int      inverse;
 108 static int      longfmt;
 109 static int      matchargs;
 110 static int      fullmatch;
 111 static int      kthreads;
 112 static int      cflags = REG_EXTENDED;
 113 static kvm_t    *kd;
 114 static pid_t    mypid;
 115
 116 static struct listhead euidlist = SLIST_HEAD_INITIALIZER(list);
 117 static struct listhead ruidlist = SLIST_HEAD_INITIALIZER(list);
 118 static struct listhead rgidlist = SLIST_HEAD_INITIALIZER(list);
 119 static struct listhead pgrplist = SLIST_HEAD_INITIALIZER(list);
 120 static struct listhead ppidlist = SLIST_HEAD_INITIALIZER(list);
 121 static struct listhead tdevlist = SLIST_HEAD_INITIALIZER(list);
 122 static struct listhead sidlist = SLIST_HEAD_INITIALIZER(list);
 123 static struct listhead jidlist = SLIST_HEAD_INITIALIZER(list);
 124
 125 static void     usage(void) __attribute__((__noreturn__));
 126 static int      killact(const struct kinfo_proc *);
 127 static int      grepact(const struct kinfo_proc *);
 128 static void     makelist(struct listhead *, enum listtype, char *);
 129 static int      takepid(const char *, int);
 130
 131 int
 132 main(int argc, char **argv)
 133 {
 134         char buf[_POSIX2_LINE_MAX], *mstr, **pargv, *p, *q, *pidfile;
 135         const char *execf, *coref;
 136         int debug_opt;
 137         int i, ch, bestidx, rv, criteria, pidfromfile, pidfilelock;
 138         size_t jsz;
 139         int (*action)(const struct kinfo_proc *);
 140         struct kinfo_proc *kp;
 141         struct list *li;
 142         struct timeval best_tval;
 143         regex_t reg;
 144         regmatch_t regmatch;
 145
 146         setlocale(LC_ALL, "");
 147
 148         if (strcmp(getprogname(), "pgrep") == 0) {
 149                 action = grepact;
 150                 pgrep = 1;
 151         } else {
 152                 action = killact;
 153                 p = argv[1];
 154
 155                 if (argc > 1 && p[0] == '-') {
 156                         p++;
 157                         i = (int)strtol(p, &q, 10);
 158                         if (*q == '\0') {
 159                                 signum = i;
 160                                 argv++;
 161                                 argc--;
 162                         } else {
 163                                 if (strncasecmp(p, "sig", 3) == 0)
 164                                         p += 3;
 165                                 for (i = 1; i < NSIG; i++)
 166                                         if (strcasecmp(sys_signame[i], p) == 0)
 167                                                 break;
 168                                 if (i != NSIG) {
 169                                         signum = i;
 170                                         argv++;
 171                                         argc--;
 172                                 }
 173                         }
 174                 }
 175         }
 176
 177         criteria = 0;
 178         debug_opt = 0;
 179         pidfile = NULL;
 180         pidfilelock = 0;
 181         execf = coref = _PATH_DEVNULL;
 182
 183         while ((ch = getopt(argc, argv, "DF:G:ILM:N:P:SU:d:fg:ij:lnos:t:u:vx")) != -1)
 184                 switch (ch) {
 185                 case 'D':
 186                         debug_opt++;
 187                         break;
 188                 case 'F':
 189                         pidfile = optarg;
 190                         criteria = 1;
 191                         break;
 192                 case 'G':
 193                         makelist(&rgidlist, LT_GROUP, optarg);
 194                         criteria = 1;
 195                         break;
 196                 case 'I':
 197                         if (pgrep)
 198                                 usage();
 199                         interactive = 1;
 200                         break;
 201                 case 'L':
 202                         pidfilelock = 1;
 203                         break;
 204                 case 'M':
 205                         coref = optarg;
 206                         break;
 207                 case 'N':
 208                         execf = optarg;
 209                         break;
 210                 case 'P':
 211                         makelist(&ppidlist, LT_GENERIC, optarg);
 212                         criteria = 1;
 213                         break;
 214                 case 'S':
 215                         if (!pgrep)
 216                                 usage();
 217                         kthreads = 1;
 218                         break;
 219                 case 'U':
 220                         makelist(&ruidlist, LT_USER, optarg);
 221                         criteria = 1;
 222                         break;
 223                 case 'd':
 224                         if (!pgrep)
 225                                 usage();
 226                         delim = optarg;
 227                         break;
 228                 case 'f':
 229                         matchargs = 1;
 230                         break;
 231                 case 'g':
 232                         makelist(&pgrplist, LT_PGRP, optarg);
 233                         criteria = 1;
 234                         break;
 235                 case 'i':
 236                         cflags |= REG_ICASE;
 237                         break;
 238                 case 'j':
 239                         makelist(&jidlist, LT_JID, optarg);
 240                         criteria = 1;
 241                         break;
 242                 case 'l':
 243                         if (!pgrep)
 244                                 usage();
 245                         longfmt = 1;
 246                         break;
 247                 case 'n':
 248                         newest = 1;
 249                         criteria = 1;
 250                         break;
 251                 case 'o':
 252                         oldest = 1;
 253                         criteria = 1;
 254                         break;
 255                 case 's':
 256                         makelist(&sidlist, LT_SID, optarg);
 257                         criteria = 1;
 258                         break;
 259                 case 't':
 260                         makelist(&tdevlist, LT_TTY, optarg);
 261                         criteria = 1;
 262                         break;
 263                 case 'u':
 264                         makelist(&euidlist, LT_USER, optarg);
 265                         criteria = 1;
 266                         break;
 267                 case 'v':
 268                         inverse = 1;
 269                         break;
 270                 case 'x':
 271                         fullmatch = 1;
 272                         break;
 273                 default:
 274                         usage();
 275                         /* NOTREACHED */
 276                 }
 277
 278         argc -= optind;
 279         argv += optind;
 280         if (argc != 0)
 281                 criteria = 1;
 282         if (!criteria)
 283                 usage();
 284         if (newest && oldest)
 285                 errx(STATUS_ERROR, "Options -n and -o are mutually exclusive");
 286         if (pidfile != NULL)
 287                 pidfromfile = takepid(pidfile, pidfilelock);
 288         else {
 289                 if (pidfilelock) {
 290                         errx(STATUS_ERROR,
 291                             "Option -L doesn't make sense without -F");
 292                 }
 293                 pidfromfile = -1;
 294         }
 295
 296         mypid = getpid();
 297
 298         /*
 299          * Retrieve the list of running processes from the kernel.
 300          */
 301         kd = kvm_openfiles(execf, coref, NULL, O_RDONLY, buf);
 302         if (kd == NULL)
 303                 errx(STATUS_ERROR, "Cannot open kernel files (%s)", buf);
 304
 305         /*
 306          * Use KERN_PROC_PROC instead of KERN_PROC_ALL, since we
 307          * just want processes and not individual kernel threads.
 308          */
 309         plist = kvm_getprocs(kd, KERN_PROC_PROC, 0, &nproc);
 310         if (plist == NULL) {
 311                 errx(STATUS_ERROR, "Cannot get process list (%s)",
 312                     kvm_geterr(kd));
 313         }
 314
 315         /*
 316          * Allocate memory which will be used to keep track of the
 317          * selection.
 318          */
 319         if ((selected = malloc(nproc)) == NULL) {
 320                 err(STATUS_ERROR, "Cannot allocate memory for %d processes",
 321                     nproc);
 322         }
 323         memset(selected, 0, nproc);
 324
 325         /*
 326          * Refine the selection.
 327          */
 328         for (; *argv != NULL; argv++) {
 329                 if ((rv = regcomp(&reg, *argv, cflags)) != 0) {
 330                         regerror(rv, &reg, buf, sizeof(buf));
 331                         errx(STATUS_BADUSAGE,
 332                             "Cannot compile regular expression `%s' (%s)",
 333                             *argv, buf);
 334                 }
 335
 336                 for (i = 0, kp = plist; i < nproc; i++, kp++) {
 337                         if (PSKIP(kp)) {
 338                                 if (debug_opt > 0)
 339                                     fprintf(stderr, "* Skipped %5d %3d %s\n",
 340                                         kp->ki_pid, kp->ki_uid, kp->ki_comm);
 341                                 continue;
 342                         }
 343
 344                         if (matchargs &&
 345                             (pargv = kvm_getargv(kd, kp, 0)) != NULL) {
 346                                 jsz = 0;
 347                                 while (jsz < sizeof(buf) && *pargv != NULL) {
 348                                         jsz += snprintf(buf + jsz,
 349                                             sizeof(buf) - jsz,
 350                                             pargv[1] != NULL ? "%s " : "%s",
 351                                             pargv[0]);
 352                                         pargv++;
 353                                 }
 354                                 mstr = buf;
 355                         } else
 356                                 mstr = kp->ki_comm;
 357
 358                         rv = regexec(&reg, mstr, 1, &regmatch, 0);
 359                         if (rv == 0) {
 360                                 if (fullmatch) {
 361                                         if (regmatch.rm_so == 0 &&
 362                                             regmatch.rm_eo ==
 363                                             (off_t)strlen(mstr))
 364                                                 selected[i] = 1;
 365                                 } else
 366                                         selected[i] = 1;
 367                         } else if (rv != REG_NOMATCH) {
 368                                 regerror(rv, &reg, buf, sizeof(buf));
 369                                 errx(STATUS_ERROR,
 370                                     "Regular expression evaluation error (%s)",
 371                                     buf);
 372                         }
 373                         if (debug_opt > 1) {
 374                                 const char *rv_res = "NoMatch";
 375                                 if (selected[i])
 376                                         rv_res = "Matched";
 377                                 fprintf(stderr, "* %s %5d %3d %s\n", rv_res,
 378                                     kp->ki_pid, kp->ki_uid, mstr);
 379                         }
 380                 }
 381
 382                 regfree(&reg);
 383         }
 384
 385         for (i = 0, kp = plist; i < nproc; i++, kp++) {
 386                 if (PSKIP(kp))
 387                         continue;
 388
 389                 if (pidfromfile >= 0 && kp->ki_pid != pidfromfile) {
 390                         selected[i] = 0;
 391                         continue;
 392                 }
 393
 394                 SLIST_FOREACH(li, &ruidlist, li_chain)
 395                         if (kp->ki_ruid == (uid_t)li->li_number)
 396                                 break;
 397                 if (SLIST_FIRST(&ruidlist) != NULL && li == NULL) {
 398                         selected[i] = 0;
 399                         continue;
 400                 }
 401
 402                 SLIST_FOREACH(li, &rgidlist, li_chain)
 403                         if (kp->ki_rgid == (gid_t)li->li_number)
 404                                 break;
 405                 if (SLIST_FIRST(&rgidlist) != NULL && li == NULL) {
 406                         selected[i] = 0;
 407                         continue;
 408                 }
 409
 410                 SLIST_FOREACH(li, &euidlist, li_chain)
 411                         if (kp->ki_uid == (uid_t)li->li_number)
 412                                 break;
 413                 if (SLIST_FIRST(&euidlist) != NULL && li == NULL) {
 414                         selected[i] = 0;
 415                         continue;
 416                 }
 417
 418                 SLIST_FOREACH(li, &ppidlist, li_chain)
 419                         if (kp->ki_ppid == (pid_t)li->li_number)
 420                                 break;
 421                 if (SLIST_FIRST(&ppidlist) != NULL && li == NULL) {
 422                         selected[i] = 0;
 423                         continue;
 424                 }
 425
 426                 SLIST_FOREACH(li, &pgrplist, li_chain)
 427                         if (kp->ki_pgid == (pid_t)li->li_number)
 428                                 break;
 429                 if (SLIST_FIRST(&pgrplist) != NULL && li == NULL) {
 430                         selected[i] = 0;
 431                         continue;
 432                 }
 433
 434                 SLIST_FOREACH(li, &tdevlist, li_chain) {
 435                         if (li->li_number == -1 &&
 436                             (kp->ki_flag & P_CONTROLT) == 0)
 437                                 break;
 438                         if (kp->ki_tdev == (dev_t)li->li_number)
 439                                 break;
 440                 }
 441                 if (SLIST_FIRST(&tdevlist) != NULL && li == NULL) {
 442                         selected[i] = 0;
 443                         continue;
 444                 }
 445
 446                 SLIST_FOREACH(li, &sidlist, li_chain)
 447                         if (kp->ki_sid == (pid_t)li->li_number)
 448                                 break;
 449                 if (SLIST_FIRST(&sidlist) != NULL && li == NULL) {
 450                         selected[i] = 0;
 451                         continue;
 452                 }
 453
 454                 SLIST_FOREACH(li, &jidlist, li_chain) {
 455                         /* A particular jail ID, including 0 (not in jail) */
 456                         if (kp->ki_jid == (int)li->li_number)
 457                                 break;
 458                         /* Any jail */
 459                         if (kp->ki_jid > 0 && li->li_number == -1)
 460                                 break;
 461                 }
 462                 if (SLIST_FIRST(&jidlist) != NULL && li == NULL) {
 463                         selected[i] = 0;
 464                         continue;
 465                 }
 466
 467                 if (argc == 0)
 468                         selected[i] = 1;
 469         }
 470
 471         if (newest || oldest) {
 472                 best_tval.tv_sec = 0;
 473                 best_tval.tv_usec = 0;
 474                 bestidx = -1;
 475
 476                 for (i = 0, kp = plist; i < nproc; i++, kp++) {
 477                         if (!selected[i])
 478                                 continue;
 479                         if (bestidx == -1) {
 480                                 /* The first entry of the list which matched. */
 481                                 ;
 482                         } else if (timercmp(&kp->ki_start, &best_tval, >)) {
 483                                 /* This entry is newer than previous "best". */
 484                                 if (oldest)     /* but we want the oldest */
 485                                         continue;
 486                         } else {
 487                                 /* This entry is older than previous "best". */
 488                                 if (newest)     /* but we want the newest */
 489                                         continue;
 490                         }
 491                         /* This entry is better than previous "best" entry. */
 492                         best_tval.tv_sec = kp->ki_start.tv_sec;
 493                         best_tval.tv_usec = kp->ki_start.tv_usec;
 494                         bestidx = i;
 495                 }
 496
 497                 memset(selected, 0, nproc);
 498                 if (bestidx != -1)
 499                         selected[bestidx] = 1;
 500         }
 501
 502         /*
 503          * Take the appropriate action for each matched process, if any.
 504          */
 505         for (i = 0, rv = 0, kp = plist; i < nproc; i++, kp++) {
 506                 if (PSKIP(kp))
 507                         continue;
 508                 if (selected[i]) {
 509                         if (inverse)
 510                                 continue;
 511                 } else if (!inverse)
 512                         continue;
 513                 rv |= (*action)(kp);
 514         }
 515
 516         exit(rv ? STATUS_MATCH : STATUS_NOMATCH);
 517 }
 518
 519 static void
 520 usage(void)
 521 {
 522         const char *ustr;
 523
 524         if (pgrep)
 525                 ustr = "[-LSfilnovx] [-d delim]";
 526         else
 527                 ustr = "[-signal] [-ILfinovx]";
 528
 529         fprintf(stderr,
 530                 "usage: %s %s [-F pidfile] [-G gid] [-M core] [-N system]\n"
 531                 "             [-P ppid] [-U uid] [-g pgrp] [-j jid] [-s sid]\n"
 532                 "             [-t tty] [-u euid] pattern ...\n", getprogname(),
 533                 ustr);
 534
 535         exit(STATUS_BADUSAGE);
 536 }
 537
 538 static void
 539 show_process(const struct kinfo_proc *kp)
 540 {
 541         char **argv;
 542
 543         if ((longfmt || !pgrep) && matchargs &&
 544             (argv = kvm_getargv(kd, kp, 0)) != NULL) {
 545                 printf("%d ", (int)kp->ki_pid);
 546                 for (; *argv != NULL; argv++) {
 547                         printf("%s", *argv);
 548                         if (argv[1] != NULL)
 549                                 putchar(' ');
 550                 }
 551         } else if (longfmt || !pgrep)
 552                 printf("%d %s", (int)kp->ki_pid, kp->ki_comm);
 553         else
 554                 printf("%d", (int)kp->ki_pid);
 555 }
 556
 557 static int
 558 killact(const struct kinfo_proc *kp)
 559 {
 560         int ch, first;
 561
 562         if (interactive) {
 563                 /*
 564                  * Be careful, ask before killing.
 565                  */
 566                 printf("kill ");
 567                 show_process(kp);
 568                 printf("? ");
 569                 fflush(stdout);
 570                 first = ch = getchar();
 571                 while (ch != '\n' && ch != EOF)
 572                         ch = getchar();
 573                 if (first != 'y' && first != 'Y')
 574                         return (1);
 575         }
 576         if (kill(kp->ki_pid, signum) == -1) {
 577                 /*
 578                  * Check for ESRCH, which indicates that the process
 579                  * disappeared between us matching it and us
 580                  * signalling it; don't issue a warning about it.
 581                  */
 582                 if (errno != ESRCH)
 583                         warn("signalling pid %d", (int)kp->ki_pid);
 584                 /*
 585                  * Return 0 to indicate that the process should not be
 586                  * considered a match, since we didn't actually get to
 587                  * signal it.
 588                  */
 589                 return (0);
 590         }
 591         return (1);
 592 }
 593
 594 static int
 595 grepact(const struct kinfo_proc *kp)
 596 {
 597
 598         show_process(kp);
 599         printf("%s", delim);
 600         return (1);
 601 }
 602
 603 static void
 604 makelist(struct listhead *head, enum listtype type, char *src)
 605 {
 606         struct list *li;
 607         struct passwd *pw;
 608         struct group *gr;
 609         struct stat st;
 610         const char *cp, *prefix;
 611         char *sp, *ep, buf[MAXPATHLEN];
 612         int empty;
 613
 614         empty = 1;
 615         prefix = _PATH_DEV;
 616
 617         while ((sp = strsep(&src, ",")) != NULL) {
 618                 if (*sp == '\0')
 619                         usage();
 620
 621                 if ((li = malloc(sizeof(*li))) == NULL) {
 622                         err(STATUS_ERROR, "Cannot allocate %zu bytes",
 623                             sizeof(*li));
 624                 }
 625
 626                 SLIST_INSERT_HEAD(head, li, li_chain);
 627                 empty = 0;
 628
 629                 li->li_number = (uid_t)strtol(sp, &ep, 0);
 630                 if (*ep == '\0') {
 631                         switch (type) {
 632                         case LT_PGRP:
 633                                 if (li->li_number == 0)
 634                                         li->li_number = getpgrp();
 635                                 break;
 636                         case LT_SID:
 637                                 if (li->li_number == 0)
 638                                         li->li_number = getsid(mypid);
 639                                 break;
 640                         case LT_JID:
 641                                 if (li->li_number < 0)
 642                                         errx(STATUS_BADUSAGE,
 643                                              "Negative jail ID `%s'", sp);
 644                                 /* For compatibility with old -j */
 645                                 if (li->li_number == 0)
 646                                         li->li_number = -1;     /* any jail */
 647                                 break;
 648                         case LT_TTY:
 649                                 usage();
 650                                 /* NOTREACHED */
 651                         default:
 652                                 break;
 653                         }
 654                         continue;
 655                 }
 656
 657                 switch (type) {
 658                 case LT_USER:
 659                         if ((pw = getpwnam(sp)) == NULL)
 660                                 errx(STATUS_BADUSAGE, "Unknown user `%s'", sp);
 661                         li->li_number = pw->pw_uid;
 662                         break;
 663                 case LT_GROUP:
 664                         if ((gr = getgrnam(sp)) == NULL)
 665                                 errx(STATUS_BADUSAGE, "Unknown group `%s'", sp);
 666                         li->li_number = gr->gr_gid;
 667                         break;
 668                 case LT_TTY:
 669                         if (strcmp(sp, "-") == 0) {
 670                                 li->li_number = -1;
 671                                 break;
 672                         } else if (strcmp(sp, "co") == 0) {
 673                                 cp = "console";
 674                         } else {
 675                                 cp = sp;
 676                                 if (strncmp(sp, "tty", 3) != 0)
 677                                         prefix = _PATH_TTY;
 678                         }
 679
 680                         snprintf(buf, sizeof(buf), "%s%s", prefix, cp);
 681
 682                         if (stat(buf, &st) == -1) {
 683                                 if (errno == ENOENT) {
 684                                         errx(STATUS_BADUSAGE,
 685                                             "No such tty: `%s'", sp);
 686                                 }
 687                                 err(STATUS_ERROR, "Cannot access `%s'", sp);
 688                         }
 689
 690                         if ((st.st_mode & S_IFCHR) == 0)
 691                                 errx(STATUS_BADUSAGE, "Not a tty: `%s'", sp);
 692
 693                         li->li_number = st.st_rdev;
 694                         break;
 695                 case LT_JID:
 696                         if (strcmp(sp, "none") == 0)
 697                                 li->li_number = 0;
 698                         else if (strcmp(sp, "any") == 0)
 699                                 li->li_number = -1;
 700                         else if (*ep != '\0')
 701                                 errx(STATUS_BADUSAGE,
 702                                      "Invalid jail ID `%s'", sp);
 703                         break;
 704                 default:
 705                         usage();
 706                 }
 707         }
 708
 709         if (empty)
 710                 usage();
 711 }
 712
 713 static int
 714 takepid(const char *pidfile, int pidfilelock)
 715 {
 716         char *endp, line[BUFSIZ];
 717         FILE *fh;
 718         long rval;
 719
 720         fh = fopen(pidfile, "r");
 721         if (fh == NULL)
 722                 err(STATUS_ERROR, "Cannot open pidfile `%s'", pidfile);
 723
 724         if (pidfilelock) {
 725                 /*
 726                  * If we can lock pidfile, this means that daemon is not
 727                  * running, so would be better not to kill some random process.
 728                  */
 729                 if (flock(fileno(fh), LOCK_EX | LOCK_NB) == 0) {
 730                         (void)fclose(fh);
 731                         errx(STATUS_ERROR, "File '%s' can be locked", pidfile);
 732                 } else {
 733                         if (errno != EWOULDBLOCK) {
 734                                 errx(STATUS_ERROR,
 735                                     "Error while locking file '%s'", pidfile);
 736                         }
 737                 }
 738         }
 739
 740         if (fgets(line, sizeof(line), fh) == NULL) {
 741                 if (feof(fh)) {
 742                         (void)fclose(fh);
 743                         errx(STATUS_ERROR, "Pidfile `%s' is empty", pidfile);
 744                 }
 745                 (void)fclose(fh);
 746                 err(STATUS_ERROR, "Cannot read from pid file `%s'", pidfile);
 747         }
 748         (void)fclose(fh);
 749
 750         rval = strtol(line, &endp, 10);
 751         if (*endp != '\0' && !isspace((unsigned char)*endp))
 752                 errx(STATUS_ERROR, "Invalid pid in file `%s'", pidfile);
 753         else if (rval < MIN_PID || rval > MAX_PID)
 754                 errx(STATUS_ERROR, "Invalid pid in file `%s'", pidfile);
 755         return (rval);
 756 }