xref: /freebsd/bin/pkill/pkill.c (revision 9fd69f37d28cfd7438cac3eeb45fe9dd46b4d7dd)
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 <assert.h>
53 #include <stdio.h>
54 #include <stdlib.h>
55 #include <limits.h>
56 #include <paths.h>
57 #include <string.h>
58 #include <unistd.h>
59 #include <signal.h>
60 #include <regex.h>
61 #include <ctype.h>
62 #include <fcntl.h>
63 #include <kvm.h>
64 #include <err.h>
65 #include <pwd.h>
66 #include <grp.h>
67 #include <errno.h>
68 #include <locale.h>
69 
70 #define	STATUS_MATCH	0
71 #define	STATUS_NOMATCH	1
72 #define	STATUS_BADUSAGE	2
73 #define	STATUS_ERROR	3
74 
75 #define	MIN_PID	5
76 #define	MAX_PID	99999
77 
78 /* Ignore system-processes (if '-S' flag is not specified) and myself. */
79 #define	PSKIP(kp)	((kp)->ki_pid == mypid ||			\
80 			 (!kthreads && ((kp)->ki_flag & P_KTHREAD) != 0))
81 
82 enum listtype {
83 	LT_GENERIC,
84 	LT_USER,
85 	LT_GROUP,
86 	LT_TTY,
87 	LT_PGRP,
88 	LT_JID,
89 	LT_SID
90 };
91 
92 struct list {
93 	SLIST_ENTRY(list) li_chain;
94 	long	li_number;
95 };
96 
97 SLIST_HEAD(listhead, list);
98 
99 static struct kinfo_proc *plist;
100 static char	*selected;
101 static const char *delim = "\n";
102 static int	nproc;
103 static int	pgrep;
104 static int	signum = SIGTERM;
105 static int	newest;
106 static int	oldest;
107 static int	interactive;
108 static int	inverse;
109 static int	longfmt;
110 static int	matchargs;
111 static int	fullmatch;
112 static int	kthreads;
113 static int	cflags = REG_EXTENDED;
114 static int	quiet;
115 static kvm_t	*kd;
116 static pid_t	mypid;
117 
118 static struct listhead euidlist = SLIST_HEAD_INITIALIZER(euidlist);
119 static struct listhead ruidlist = SLIST_HEAD_INITIALIZER(ruidlist);
120 static struct listhead rgidlist = SLIST_HEAD_INITIALIZER(rgidlist);
121 static struct listhead pgrplist = SLIST_HEAD_INITIALIZER(pgrplist);
122 static struct listhead ppidlist = SLIST_HEAD_INITIALIZER(ppidlist);
123 static struct listhead tdevlist = SLIST_HEAD_INITIALIZER(tdevlist);
124 static struct listhead sidlist = SLIST_HEAD_INITIALIZER(sidlist);
125 static struct listhead jidlist = SLIST_HEAD_INITIALIZER(jidlist);
126 
127 static void	usage(void) __attribute__((__noreturn__));
128 static int	killact(const struct kinfo_proc *);
129 static int	grepact(const struct kinfo_proc *);
130 static void	makelist(struct listhead *, enum listtype, char *);
131 static int	takepid(const char *, int);
132 
133 int
134 main(int argc, char **argv)
135 {
136 	char buf[_POSIX2_LINE_MAX], *mstr, **pargv, *p, *q, *pidfile;
137 	const char *execf, *coref;
138 	int ancestors, debug_opt;
139 	int i, ch, bestidx, rv, criteria, pidfromfile, pidfilelock;
140 	size_t jsz;
141 	int (*action)(const struct kinfo_proc *);
142 	struct kinfo_proc *kp;
143 	struct list *li;
144 	struct timeval best_tval;
145 	regex_t reg;
146 	regmatch_t regmatch;
147 	pid_t pid;
148 
149 	setlocale(LC_ALL, "");
150 
151 	if (strcmp(getprogname(), "pgrep") == 0) {
152 		action = grepact;
153 		pgrep = 1;
154 	} else {
155 		action = killact;
156 		p = argv[1];
157 
158 		if (argc > 1 && p[0] == '-') {
159 			p++;
160 			i = (int)strtol(p, &q, 10);
161 			if (*q == '\0') {
162 				signum = i;
163 				argv++;
164 				argc--;
165 			} else {
166 				if (strncasecmp(p, "sig", 3) == 0)
167 					p += 3;
168 				for (i = 1; i < NSIG; i++)
169 					if (strcasecmp(sys_signame[i], p) == 0)
170 						break;
171 				if (i != NSIG) {
172 					signum = i;
173 					argv++;
174 					argc--;
175 				}
176 			}
177 		}
178 	}
179 
180 	ancestors = 0;
181 	criteria = 0;
182 	debug_opt = 0;
183 	pidfile = NULL;
184 	pidfilelock = 0;
185 	quiet = 0;
186 	execf = NULL;
187 	coref = _PATH_DEVNULL;
188 
189 	while ((ch = getopt(argc, argv, "DF:G:ILM:N:P:SU:ad:fg:ij:lnoqs:t:u:vx")) != -1)
190 		switch (ch) {
191 		case 'D':
192 			debug_opt++;
193 			break;
194 		case 'F':
195 			pidfile = optarg;
196 			criteria = 1;
197 			break;
198 		case 'G':
199 			makelist(&rgidlist, LT_GROUP, optarg);
200 			criteria = 1;
201 			break;
202 		case 'I':
203 			if (pgrep)
204 				usage();
205 			interactive = 1;
206 			break;
207 		case 'L':
208 			pidfilelock = 1;
209 			break;
210 		case 'M':
211 			coref = optarg;
212 			break;
213 		case 'N':
214 			execf = optarg;
215 			break;
216 		case 'P':
217 			makelist(&ppidlist, LT_GENERIC, optarg);
218 			criteria = 1;
219 			break;
220 		case 'S':
221 			if (!pgrep)
222 				usage();
223 			kthreads = 1;
224 			break;
225 		case 'U':
226 			makelist(&ruidlist, LT_USER, optarg);
227 			criteria = 1;
228 			break;
229 		case 'a':
230 			ancestors++;
231 			break;
232 		case 'd':
233 			if (!pgrep)
234 				usage();
235 			delim = optarg;
236 			break;
237 		case 'f':
238 			matchargs = 1;
239 			break;
240 		case 'g':
241 			makelist(&pgrplist, LT_PGRP, optarg);
242 			criteria = 1;
243 			break;
244 		case 'i':
245 			cflags |= REG_ICASE;
246 			break;
247 		case 'j':
248 			makelist(&jidlist, LT_JID, optarg);
249 			criteria = 1;
250 			break;
251 		case 'l':
252 			if (!pgrep)
253 				usage();
254 			longfmt = 1;
255 			break;
256 		case 'n':
257 			newest = 1;
258 			criteria = 1;
259 			break;
260 		case 'o':
261 			oldest = 1;
262 			criteria = 1;
263 			break;
264 		case 'q':
265 			if (!pgrep)
266 				usage();
267 			quiet = 1;
268 			break;
269 		case 's':
270 			makelist(&sidlist, LT_SID, optarg);
271 			criteria = 1;
272 			break;
273 		case 't':
274 			makelist(&tdevlist, LT_TTY, optarg);
275 			criteria = 1;
276 			break;
277 		case 'u':
278 			makelist(&euidlist, LT_USER, optarg);
279 			criteria = 1;
280 			break;
281 		case 'v':
282 			inverse = 1;
283 			break;
284 		case 'x':
285 			fullmatch = 1;
286 			break;
287 		default:
288 			usage();
289 			/* NOTREACHED */
290 		}
291 
292 	argc -= optind;
293 	argv += optind;
294 	if (argc != 0)
295 		criteria = 1;
296 	if (!criteria)
297 		usage();
298 	if (newest && oldest)
299 		errx(STATUS_ERROR, "Options -n and -o are mutually exclusive");
300 	if (pidfile != NULL)
301 		pidfromfile = takepid(pidfile, pidfilelock);
302 	else {
303 		if (pidfilelock) {
304 			errx(STATUS_ERROR,
305 			    "Option -L doesn't make sense without -F");
306 		}
307 		pidfromfile = -1;
308 	}
309 
310 	mypid = getpid();
311 
312 	/*
313 	 * Retrieve the list of running processes from the kernel.
314 	 */
315 	kd = kvm_openfiles(execf, coref, NULL, O_RDONLY, buf);
316 	if (kd == NULL)
317 		errx(STATUS_ERROR, "Cannot open kernel files (%s)", buf);
318 
319 	/*
320 	 * Use KERN_PROC_PROC instead of KERN_PROC_ALL, since we
321 	 * just want processes and not individual kernel threads.
322 	 */
323 	plist = kvm_getprocs(kd, KERN_PROC_PROC, 0, &nproc);
324 	if (plist == NULL) {
325 		errx(STATUS_ERROR, "Cannot get process list (%s)",
326 		    kvm_geterr(kd));
327 	}
328 
329 	/*
330 	 * Allocate memory which will be used to keep track of the
331 	 * selection.
332 	 */
333 	if ((selected = malloc(nproc)) == NULL) {
334 		err(STATUS_ERROR, "Cannot allocate memory for %d processes",
335 		    nproc);
336 	}
337 	memset(selected, 0, nproc);
338 
339 	/*
340 	 * Refine the selection.
341 	 */
342 	for (; *argv != NULL; argv++) {
343 		if ((rv = regcomp(&reg, *argv, cflags)) != 0) {
344 			regerror(rv, &reg, buf, sizeof(buf));
345 			errx(STATUS_BADUSAGE,
346 			    "Cannot compile regular expression `%s' (%s)",
347 			    *argv, buf);
348 		}
349 
350 		for (i = 0, kp = plist; i < nproc; i++, kp++) {
351 			if (PSKIP(kp)) {
352 				if (debug_opt > 0)
353 				    fprintf(stderr, "* Skipped %5d %3d %s\n",
354 					kp->ki_pid, kp->ki_uid, kp->ki_comm);
355 				continue;
356 			}
357 
358 			if (matchargs &&
359 			    (pargv = kvm_getargv(kd, kp, 0)) != NULL) {
360 				jsz = 0;
361 				while (jsz < sizeof(buf) && *pargv != NULL) {
362 					jsz += snprintf(buf + jsz,
363 					    sizeof(buf) - jsz,
364 					    pargv[1] != NULL ? "%s " : "%s",
365 					    pargv[0]);
366 					pargv++;
367 				}
368 				mstr = buf;
369 			} else
370 				mstr = kp->ki_comm;
371 
372 			rv = regexec(&reg, mstr, 1, &regmatch, 0);
373 			if (rv == 0) {
374 				if (fullmatch) {
375 					if (regmatch.rm_so == 0 &&
376 					    regmatch.rm_eo ==
377 					    (off_t)strlen(mstr))
378 						selected[i] = 1;
379 				} else
380 					selected[i] = 1;
381 			} else if (rv != REG_NOMATCH) {
382 				regerror(rv, &reg, buf, sizeof(buf));
383 				errx(STATUS_ERROR,
384 				    "Regular expression evaluation error (%s)",
385 				    buf);
386 			}
387 			if (debug_opt > 1) {
388 				const char *rv_res = "NoMatch";
389 				if (selected[i])
390 					rv_res = "Matched";
391 				fprintf(stderr, "* %s %5d %3d %s\n", rv_res,
392 				    kp->ki_pid, kp->ki_uid, mstr);
393 			}
394 		}
395 
396 		regfree(&reg);
397 	}
398 
399 	for (i = 0, kp = plist; i < nproc; i++, kp++) {
400 		if (PSKIP(kp))
401 			continue;
402 
403 		if (pidfromfile >= 0 && kp->ki_pid != pidfromfile) {
404 			selected[i] = 0;
405 			continue;
406 		}
407 
408 		SLIST_FOREACH(li, &ruidlist, li_chain)
409 			if (kp->ki_ruid == (uid_t)li->li_number)
410 				break;
411 		if (SLIST_FIRST(&ruidlist) != NULL && li == NULL) {
412 			selected[i] = 0;
413 			continue;
414 		}
415 
416 		SLIST_FOREACH(li, &rgidlist, li_chain)
417 			if (kp->ki_rgid == (gid_t)li->li_number)
418 				break;
419 		if (SLIST_FIRST(&rgidlist) != NULL && li == NULL) {
420 			selected[i] = 0;
421 			continue;
422 		}
423 
424 		SLIST_FOREACH(li, &euidlist, li_chain)
425 			if (kp->ki_uid == (uid_t)li->li_number)
426 				break;
427 		if (SLIST_FIRST(&euidlist) != NULL && li == NULL) {
428 			selected[i] = 0;
429 			continue;
430 		}
431 
432 		SLIST_FOREACH(li, &ppidlist, li_chain)
433 			if (kp->ki_ppid == (pid_t)li->li_number)
434 				break;
435 		if (SLIST_FIRST(&ppidlist) != NULL && li == NULL) {
436 			selected[i] = 0;
437 			continue;
438 		}
439 
440 		SLIST_FOREACH(li, &pgrplist, li_chain)
441 			if (kp->ki_pgid == (pid_t)li->li_number)
442 				break;
443 		if (SLIST_FIRST(&pgrplist) != NULL && li == NULL) {
444 			selected[i] = 0;
445 			continue;
446 		}
447 
448 		SLIST_FOREACH(li, &tdevlist, li_chain) {
449 			if (li->li_number == -1 &&
450 			    (kp->ki_flag & P_CONTROLT) == 0)
451 				break;
452 			if (kp->ki_tdev == (dev_t)li->li_number)
453 				break;
454 		}
455 		if (SLIST_FIRST(&tdevlist) != NULL && li == NULL) {
456 			selected[i] = 0;
457 			continue;
458 		}
459 
460 		SLIST_FOREACH(li, &sidlist, li_chain)
461 			if (kp->ki_sid == (pid_t)li->li_number)
462 				break;
463 		if (SLIST_FIRST(&sidlist) != NULL && li == NULL) {
464 			selected[i] = 0;
465 			continue;
466 		}
467 
468 		SLIST_FOREACH(li, &jidlist, li_chain) {
469 			/* A particular jail ID, including 0 (not in jail) */
470 			if (kp->ki_jid == (int)li->li_number)
471 				break;
472 			/* Any jail */
473 			if (kp->ki_jid > 0 && li->li_number == -1)
474 				break;
475 		}
476 		if (SLIST_FIRST(&jidlist) != NULL && li == NULL) {
477 			selected[i] = 0;
478 			continue;
479 		}
480 
481 		if (argc == 0)
482 			selected[i] = 1;
483 	}
484 
485 	if (!ancestors) {
486 		pid = mypid;
487 		while (pid) {
488 			for (i = 0, kp = plist; i < nproc; i++, kp++) {
489 				if (PSKIP(kp))
490 					continue;
491 				if (kp->ki_pid == pid) {
492 					selected[i] = 0;
493 					pid = kp->ki_ppid;
494 					break;
495 				}
496 			}
497 			if (i == nproc) {
498 				if (pid == mypid)
499 					pid = getppid();
500 				else
501 					break;	/* Maybe we're in a jail ? */
502 			}
503 		}
504 	}
505 
506 	if (newest || oldest) {
507 		best_tval.tv_sec = 0;
508 		best_tval.tv_usec = 0;
509 		bestidx = -1;
510 
511 		for (i = 0, kp = plist; i < nproc; i++, kp++) {
512 			if (!selected[i])
513 				continue;
514 			if (bestidx == -1) {
515 				/* The first entry of the list which matched. */
516 				;
517 			} else if (timercmp(&kp->ki_start, &best_tval, >)) {
518 				/* This entry is newer than previous "best". */
519 				if (oldest)	/* but we want the oldest */
520 					continue;
521 			} else {
522 				/* This entry is older than previous "best". */
523 				if (newest)	/* but we want the newest */
524 					continue;
525 			}
526 			/* This entry is better than previous "best" entry. */
527 			best_tval.tv_sec = kp->ki_start.tv_sec;
528 			best_tval.tv_usec = kp->ki_start.tv_usec;
529 			bestidx = i;
530 		}
531 
532 		memset(selected, 0, nproc);
533 		if (bestidx != -1)
534 			selected[bestidx] = 1;
535 	}
536 
537 	/*
538 	 * Take the appropriate action for each matched process, if any.
539 	 */
540 	for (i = 0, rv = 0, kp = plist; i < nproc; i++, kp++) {
541 		if (PSKIP(kp))
542 			continue;
543 		if (selected[i]) {
544 			if (inverse)
545 				continue;
546 		} else if (!inverse)
547 			continue;
548 		rv |= (*action)(kp);
549 	}
550 
551 	exit(rv ? STATUS_MATCH : STATUS_NOMATCH);
552 }
553 
554 static void
555 usage(void)
556 {
557 	const char *ustr;
558 
559 	if (pgrep)
560 		ustr = "[-LSfilnoqvx] [-d delim]";
561 	else
562 		ustr = "[-signal] [-ILfinovx]";
563 
564 	fprintf(stderr,
565 		"usage: %s %s [-F pidfile] [-G gid] [-M core] [-N system]\n"
566 		"             [-P ppid] [-U uid] [-g pgrp] [-j jid] [-s sid]\n"
567 		"             [-t tty] [-u euid] pattern ...\n", getprogname(),
568 		ustr);
569 
570 	exit(STATUS_BADUSAGE);
571 }
572 
573 static void
574 show_process(const struct kinfo_proc *kp)
575 {
576 	char **argv;
577 
578 	if (quiet) {
579 		assert(pgrep);
580 		return;
581 	}
582 	if ((longfmt || !pgrep) && matchargs &&
583 	    (argv = kvm_getargv(kd, kp, 0)) != NULL) {
584 		printf("%d ", (int)kp->ki_pid);
585 		for (; *argv != NULL; argv++) {
586 			printf("%s", *argv);
587 			if (argv[1] != NULL)
588 				putchar(' ');
589 		}
590 	} else if (longfmt || !pgrep)
591 		printf("%d %s", (int)kp->ki_pid, kp->ki_comm);
592 	else
593 		printf("%d", (int)kp->ki_pid);
594 }
595 
596 static int
597 killact(const struct kinfo_proc *kp)
598 {
599 	int ch, first;
600 
601 	if (interactive) {
602 		/*
603 		 * Be careful, ask before killing.
604 		 */
605 		printf("kill ");
606 		show_process(kp);
607 		printf("? ");
608 		fflush(stdout);
609 		first = ch = getchar();
610 		while (ch != '\n' && ch != EOF)
611 			ch = getchar();
612 		if (first != 'y' && first != 'Y')
613 			return (1);
614 	}
615 	if (kill(kp->ki_pid, signum) == -1) {
616 		/*
617 		 * Check for ESRCH, which indicates that the process
618 		 * disappeared between us matching it and us
619 		 * signalling it; don't issue a warning about it.
620 		 */
621 		if (errno != ESRCH)
622 			warn("signalling pid %d", (int)kp->ki_pid);
623 		/*
624 		 * Return 0 to indicate that the process should not be
625 		 * considered a match, since we didn't actually get to
626 		 * signal it.
627 		 */
628 		return (0);
629 	}
630 	return (1);
631 }
632 
633 static int
634 grepact(const struct kinfo_proc *kp)
635 {
636 
637 	show_process(kp);
638 	if (!quiet)
639 		printf("%s", delim);
640 	return (1);
641 }
642 
643 static void
644 makelist(struct listhead *head, enum listtype type, char *src)
645 {
646 	struct list *li;
647 	struct passwd *pw;
648 	struct group *gr;
649 	struct stat st;
650 	const char *cp;
651 	char *sp, *ep, buf[MAXPATHLEN];
652 	int empty;
653 
654 	empty = 1;
655 
656 	while ((sp = strsep(&src, ",")) != NULL) {
657 		if (*sp == '\0')
658 			usage();
659 
660 		if ((li = malloc(sizeof(*li))) == NULL) {
661 			err(STATUS_ERROR, "Cannot allocate %zu bytes",
662 			    sizeof(*li));
663 		}
664 
665 		SLIST_INSERT_HEAD(head, li, li_chain);
666 		empty = 0;
667 
668 		li->li_number = (uid_t)strtol(sp, &ep, 0);
669 		if (*ep == '\0') {
670 			switch (type) {
671 			case LT_PGRP:
672 				if (li->li_number == 0)
673 					li->li_number = getpgrp();
674 				break;
675 			case LT_SID:
676 				if (li->li_number == 0)
677 					li->li_number = getsid(mypid);
678 				break;
679 			case LT_JID:
680 				if (li->li_number < 0)
681 					errx(STATUS_BADUSAGE,
682 					     "Negative jail ID `%s'", sp);
683 				/* For compatibility with old -j */
684 				if (li->li_number == 0)
685 					li->li_number = -1;	/* any jail */
686 				break;
687 			case LT_TTY:
688 				if (li->li_number < 0)
689 					errx(STATUS_BADUSAGE,
690 					     "Negative /dev/pts tty `%s'", sp);
691 				snprintf(buf, sizeof(buf), _PATH_DEV "pts/%s",
692 				    sp);
693 				if (stat(buf, &st) != -1)
694 					goto foundtty;
695 				if (errno == ENOENT)
696 					errx(STATUS_BADUSAGE, "No such tty: `"
697 					    _PATH_DEV "pts/%s'", sp);
698 				err(STATUS_ERROR, "Cannot access `"
699 				    _PATH_DEV "pts/%s'", sp);
700 				break;
701 			default:
702 				break;
703 			}
704 			continue;
705 		}
706 
707 		switch (type) {
708 		case LT_USER:
709 			if ((pw = getpwnam(sp)) == NULL)
710 				errx(STATUS_BADUSAGE, "Unknown user `%s'", sp);
711 			li->li_number = pw->pw_uid;
712 			break;
713 		case LT_GROUP:
714 			if ((gr = getgrnam(sp)) == NULL)
715 				errx(STATUS_BADUSAGE, "Unknown group `%s'", sp);
716 			li->li_number = gr->gr_gid;
717 			break;
718 		case LT_TTY:
719 			if (strcmp(sp, "-") == 0) {
720 				li->li_number = -1;
721 				break;
722 			} else if (strcmp(sp, "co") == 0) {
723 				cp = "console";
724 			} else {
725 				cp = sp;
726 			}
727 
728 			snprintf(buf, sizeof(buf), _PATH_DEV "%s", cp);
729 			if (stat(buf, &st) != -1)
730 				goto foundtty;
731 
732 			snprintf(buf, sizeof(buf), _PATH_DEV "tty%s", cp);
733 			if (stat(buf, &st) != -1)
734 				goto foundtty;
735 
736 			if (errno == ENOENT)
737 				errx(STATUS_BADUSAGE, "No such tty: `%s'", sp);
738 			err(STATUS_ERROR, "Cannot access `%s'", sp);
739 
740 foundtty:		if ((st.st_mode & S_IFCHR) == 0)
741 				errx(STATUS_BADUSAGE, "Not a tty: `%s'", sp);
742 
743 			li->li_number = st.st_rdev;
744 			break;
745 		case LT_JID:
746 			if (strcmp(sp, "none") == 0)
747 				li->li_number = 0;
748 			else if (strcmp(sp, "any") == 0)
749 				li->li_number = -1;
750 			else if (*ep != '\0')
751 				errx(STATUS_BADUSAGE,
752 				     "Invalid jail ID `%s'", sp);
753 			break;
754 		default:
755 			usage();
756 		}
757 	}
758 
759 	if (empty)
760 		usage();
761 }
762 
763 static int
764 takepid(const char *pidfile, int pidfilelock)
765 {
766 	char *endp, line[BUFSIZ];
767 	FILE *fh;
768 	long rval;
769 
770 	fh = fopen(pidfile, "r");
771 	if (fh == NULL)
772 		err(STATUS_ERROR, "Cannot open pidfile `%s'", pidfile);
773 
774 	if (pidfilelock) {
775 		/*
776 		 * If we can lock pidfile, this means that daemon is not
777 		 * running, so would be better not to kill some random process.
778 		 */
779 		if (flock(fileno(fh), LOCK_EX | LOCK_NB) == 0) {
780 			(void)fclose(fh);
781 			errx(STATUS_ERROR, "File '%s' can be locked", pidfile);
782 		} else {
783 			if (errno != EWOULDBLOCK) {
784 				errx(STATUS_ERROR,
785 				    "Error while locking file '%s'", pidfile);
786 			}
787 		}
788 	}
789 
790 	if (fgets(line, sizeof(line), fh) == NULL) {
791 		if (feof(fh)) {
792 			(void)fclose(fh);
793 			errx(STATUS_ERROR, "Pidfile `%s' is empty", pidfile);
794 		}
795 		(void)fclose(fh);
796 		err(STATUS_ERROR, "Cannot read from pid file `%s'", pidfile);
797 	}
798 	(void)fclose(fh);
799 
800 	rval = strtol(line, &endp, 10);
801 	if (*endp != '\0' && !isspace((unsigned char)*endp))
802 		errx(STATUS_ERROR, "Invalid pid in file `%s'", pidfile);
803 	else if (rval < MIN_PID || rval > MAX_PID)
804 		errx(STATUS_ERROR, "Invalid pid in file `%s'", pidfile);
805 	return (rval);
806 }
807