xref: /freebsd/bin/ps/ps.c (revision 02e9120893770924227138ba49df1edb3896112a)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1990, 1993, 1994
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  * ------+---------+---------+-------- + --------+---------+---------+---------*
31  * Copyright (c) 2004  - Garance Alistair Drosehn <gad@FreeBSD.org>.
32  * All rights reserved.
33  *
34  * Significant modifications made to bring `ps' options somewhat closer
35  * to the standard for `ps' as described in SingleUnixSpec-v3.
36  * ------+---------+---------+-------- + --------+---------+---------+---------*
37  */
38 
39 #include <sys/param.h>
40 #include <sys/jail.h>
41 #include <sys/proc.h>
42 #include <sys/user.h>
43 #include <sys/stat.h>
44 #include <sys/ioctl.h>
45 #include <sys/sysctl.h>
46 #include <sys/mount.h>
47 
48 #include <ctype.h>
49 #include <err.h>
50 #include <errno.h>
51 #include <fcntl.h>
52 #include <grp.h>
53 #include <jail.h>
54 #include <kvm.h>
55 #include <limits.h>
56 #include <locale.h>
57 #include <paths.h>
58 #include <pwd.h>
59 #include <stdio.h>
60 #include <stdlib.h>
61 #include <string.h>
62 #include <unistd.h>
63 #include <libxo/xo.h>
64 
65 #include "ps.h"
66 
67 #define	_PATH_PTS	"/dev/pts/"
68 
69 #define	W_SEP	" \t"		/* "Whitespace" list separators */
70 #define	T_SEP	","		/* "Terminate-element" list separators */
71 
72 #ifdef LAZY_PS
73 #define	DEF_UREAD	0
74 #define	OPT_LAZY_f	"f"
75 #else
76 #define	DEF_UREAD	1	/* Always do the more-expensive read. */
77 #define	OPT_LAZY_f		/* I.e., the `-f' option is not added. */
78 #endif
79 
80 /*
81  * isdigit takes an `int', but expects values in the range of unsigned char.
82  * This wrapper ensures that values from a 'char' end up in the correct range.
83  */
84 #define	isdigitch(Anychar) isdigit((u_char)(Anychar))
85 
86 int	 cflag;			/* -c */
87 int	 eval;			/* Exit value */
88 time_t	 now;			/* Current time(3) value */
89 int	 rawcpu;		/* -C */
90 int	 sumrusage;		/* -S */
91 int	 termwidth;		/* Width of the screen (0 == infinity). */
92 int	 showthreads;		/* will threads be shown? */
93 
94 struct velisthead varlist = STAILQ_HEAD_INITIALIZER(varlist);
95 
96 static int	 forceuread = DEF_UREAD; /* Do extra work to get u-area. */
97 static kvm_t	*kd;
98 static int	 needcomm;	/* -o "command" */
99 static int	 needenv;	/* -e */
100 static int	 needuser;	/* -o "user" */
101 static int	 optfatal;	/* Fatal error parsing some list-option. */
102 static int	 pid_max;	/* kern.pid_max */
103 
104 static enum sort { DEFAULT, SORTMEM, SORTCPU } sortby = DEFAULT;
105 
106 struct listinfo;
107 typedef	int	addelem_rtn(struct listinfo *_inf, const char *_elem);
108 
109 struct listinfo {
110 	int		 count;
111 	int		 maxcount;
112 	int		 elemsize;
113 	addelem_rtn	*addelem;
114 	const char	*lname;
115 	union {
116 		gid_t	*gids;
117 		int	*jids;
118 		pid_t	*pids;
119 		dev_t	*ttys;
120 		uid_t	*uids;
121 		void	*ptr;
122 	} l;
123 };
124 
125 static int	 addelem_gid(struct listinfo *, const char *);
126 static int	 addelem_jid(struct listinfo *, const char *);
127 static int	 addelem_pid(struct listinfo *, const char *);
128 static int	 addelem_tty(struct listinfo *, const char *);
129 static int	 addelem_uid(struct listinfo *, const char *);
130 static void	 add_list(struct listinfo *, const char *);
131 static void	 descendant_sort(KINFO *, int);
132 static void	 format_output(KINFO *);
133 static void	*expand_list(struct listinfo *);
134 static const char *
135 		 fmt(char **(*)(kvm_t *, const struct kinfo_proc *, int),
136 		    KINFO *, char *, char *, int);
137 static void	 free_list(struct listinfo *);
138 static void	 init_list(struct listinfo *, addelem_rtn, int, const char *);
139 static char	*kludge_oldps_options(const char *, char *, const char *);
140 static int	 pscomp(const void *, const void *);
141 static void	 saveuser(KINFO *);
142 static void	 scanvars(void);
143 static void	 sizevars(void);
144 static void	 pidmax_init(void);
145 static void	 usage(void);
146 
147 static char dfmt[] = "pid,tt,state,time,command";
148 static char jfmt[] = "user,pid,ppid,pgid,sid,jobc,state,tt,time,command";
149 static char lfmt[] = "uid,pid,ppid,cpu,pri,nice,vsz,rss,mwchan,state,"
150 			"tt,time,command";
151 static char   o1[] = "pid";
152 static char   o2[] = "tt,state,time,command";
153 static char ufmt[] = "user,pid,%cpu,%mem,vsz,rss,tt,state,start,time,command";
154 static char vfmt[] = "pid,state,time,sl,re,pagein,vsz,rss,lim,tsiz,"
155 			"%cpu,%mem,command";
156 static char Zfmt[] = "label";
157 
158 #define	PS_ARGS	"AaCcD:de" OPT_LAZY_f "G:gHhjJ:LlM:mN:O:o:p:rSTt:U:uvwXxZ"
159 
160 int
161 main(int argc, char *argv[])
162 {
163 	struct listinfo gidlist, jidlist, pgrplist, pidlist;
164 	struct listinfo ruidlist, sesslist, ttylist, uidlist;
165 	struct kinfo_proc *kp;
166 	KINFO *kinfo = NULL, *next_KINFO;
167 	KINFO_STR *ks;
168 	struct varent *vent;
169 	struct winsize ws = { .ws_row = 0 };
170 	const char *nlistf, *memf, *str;
171 	char *cols;
172 	int all, ch, elem, flag, _fmt, i, lineno, linelen, left;
173 	int descendancy, nentries, nkept, nselectors;
174 	int prtheader, wflag, what, xkeep, xkeep_implied;
175 	int fwidthmin, fwidthmax;
176 	char errbuf[_POSIX2_LINE_MAX];
177 	char fmtbuf[_POSIX2_LINE_MAX];
178 	enum { NONE = 0, UP = 1, DOWN = 2, BOTH = 1 | 2 } directions = NONE;
179 	struct { int traversed; int initial; } pid_count;
180 
181 	(void) setlocale(LC_ALL, "");
182 	time(&now);			/* Used by routines in print.c. */
183 
184 	/*
185 	 * Compute default output line length before processing options.
186 	 * If COLUMNS is set, use it.  Otherwise, if this is part of an
187 	 * interactive job (i.e. one associated with a terminal), use
188 	 * the terminal width.  "Interactive" is determined by whether
189 	 * any of stdout, stderr, or stdin is a terminal.  The intent
190 	 * is that "ps", "ps | more", and "ps | grep" all use the same
191 	 * default line length unless -w is specified.
192 	 *
193 	 * If not interactive, the default length was traditionally 79.
194 	 * It has been changed to unlimited.  This is mostly for the
195 	 * benefit of non-interactive scripts, which arguably should
196 	 * use -ww, but is compatible with Linux.
197 	 */
198 	if ((cols = getenv("COLUMNS")) != NULL && *cols != '\0')
199 		termwidth = atoi(cols);
200 	else if ((ioctl(STDOUT_FILENO, TIOCGWINSZ, (char *)&ws) == -1 &&
201 	     ioctl(STDERR_FILENO, TIOCGWINSZ, (char *)&ws) == -1 &&
202 	     ioctl(STDIN_FILENO,  TIOCGWINSZ, (char *)&ws) == -1) ||
203 	     ws.ws_col == 0)
204 		termwidth = UNLIMITED;
205 	else
206 		termwidth = ws.ws_col - 1;
207 
208 	/*
209 	 * Hide a number of option-processing kludges in a separate routine,
210 	 * to support some historical BSD behaviors, such as `ps axu'.
211 	 */
212 	if (argc > 1)
213 		argv[1] = kludge_oldps_options(PS_ARGS, argv[1], argv[2]);
214 
215 	pidmax_init();
216 
217 	all = descendancy = _fmt = nselectors = optfatal = 0;
218 	prtheader = showthreads = wflag = xkeep_implied = 0;
219 	xkeep = -1;			/* Neither -x nor -X. */
220 	init_list(&gidlist, addelem_gid, sizeof(gid_t), "group");
221 	init_list(&jidlist, addelem_jid, sizeof(int), "jail id");
222 	init_list(&pgrplist, addelem_pid, sizeof(pid_t), "process group");
223 	init_list(&pidlist, addelem_pid, sizeof(pid_t), "process id");
224 	init_list(&ruidlist, addelem_uid, sizeof(uid_t), "ruser");
225 	init_list(&sesslist, addelem_pid, sizeof(pid_t), "session id");
226 	init_list(&ttylist, addelem_tty, sizeof(dev_t), "tty");
227 	init_list(&uidlist, addelem_uid, sizeof(uid_t), "user");
228 	memf = _PATH_DEVNULL;
229 	nlistf = NULL;
230 
231 	argc = xo_parse_args(argc, argv);
232 	if (argc < 0)
233 		exit(1);
234 
235 	while ((ch = getopt(argc, argv, PS_ARGS)) != -1)
236 		switch (ch) {
237 		case 'A':
238 			/*
239 			 * Exactly the same as `-ax'.   This has been
240 			 * added for compatibility with SUSv3, but for
241 			 * now it will not be described in the man page.
242 			 */
243 			all = xkeep = 1;
244 			break;
245 		case 'a':
246 			all = 1;
247 			break;
248 		case 'C':
249 			rawcpu = 1;
250 			break;
251 		case 'c':
252 			cflag = 1;
253 			break;
254 		case 'D': {
255 				size_t len = strlen(optarg);
256 
257 				if (len <= 2 &&
258 					strncasecmp(optarg, "up", len) == 0)
259 					directions |= UP;
260 				else if (len <= 4 &&
261 					strncasecmp(optarg, "down", len) == 0)
262 					directions |= DOWN;
263 				else if (len <= 4 &&
264 					strncasecmp(optarg, "both", len) == 0)
265 					directions |= BOTH;
266 				break;
267 			}
268 		case 'd':
269 			descendancy = 1;
270 			break;
271 		case 'e':			/* XXX set ufmt */
272 			needenv = 1;
273 			break;
274 #ifdef LAZY_PS
275 		case 'f':
276 			if (getuid() == 0 || getgid() == 0)
277 				forceuread = 1;
278 			break;
279 #endif
280 		case 'G':
281 			add_list(&gidlist, optarg);
282 			xkeep_implied = 1;
283 			nselectors++;
284 			break;
285 		case 'g':
286 #if 0
287 			/*-
288 			 * XXX - This SUSv3 behavior is still under debate
289 			 *	since it conflicts with the (undocumented)
290 			 *	`-g' option.  So we skip it for now.
291 			 */
292 			add_list(&pgrplist, optarg);
293 			xkeep_implied = 1;
294 			nselectors++;
295 			break;
296 #else
297 			/* The historical BSD-ish (from SunOS) behavior. */
298 			break;			/* no-op */
299 #endif
300 		case 'H':
301 			showthreads = KERN_PROC_INC_THREAD;
302 			break;
303 		case 'h':
304 			prtheader = ws.ws_row > 5 ? ws.ws_row : 22;
305 			break;
306 		case 'J':
307 			add_list(&jidlist, optarg);
308 			xkeep_implied = 1;
309 			nselectors++;
310 			break;
311 		case 'j':
312 			parsefmt(jfmt, 0);
313 			_fmt = 1;
314 			jfmt[0] = '\0';
315 			break;
316 		case 'L':
317 			showkey();
318 			exit(0);
319 		case 'l':
320 			parsefmt(lfmt, 0);
321 			_fmt = 1;
322 			lfmt[0] = '\0';
323 			break;
324 		case 'M':
325 			memf = optarg;
326 			break;
327 		case 'm':
328 			sortby = SORTMEM;
329 			break;
330 		case 'N':
331 			nlistf = optarg;
332 			break;
333 		case 'O':
334 			parsefmt(o1, 1);
335 			parsefmt(optarg, 1);
336 			parsefmt(o2, 1);
337 			o1[0] = o2[0] = '\0';
338 			_fmt = 1;
339 			break;
340 		case 'o':
341 			parsefmt(optarg, 1);
342 			_fmt = 1;
343 			break;
344 		case 'p':
345 			add_list(&pidlist, optarg);
346 			/*
347 			 * Note: `-p' does not *set* xkeep, but any values
348 			 * from pidlist are checked before xkeep is.  That
349 			 * way they are always matched, even if the user
350 			 * specifies `-X'.
351 			 */
352 			nselectors++;
353 			break;
354 #if 0
355 		case 'R':
356 			/*-
357 			 * XXX - This un-standard option is still under
358 			 *	debate.  This is what SUSv3 defines as
359 			 *	the `-U' option, and while it would be
360 			 *	nice to have, it could cause even more
361 			 *	confusion to implement it as `-R'.
362 			 */
363 			add_list(&ruidlist, optarg);
364 			xkeep_implied = 1;
365 			nselectors++;
366 			break;
367 #endif
368 		case 'r':
369 			sortby = SORTCPU;
370 			break;
371 		case 'S':
372 			sumrusage = 1;
373 			break;
374 #if 0
375 		case 's':
376 			/*-
377 			 * XXX - This non-standard option is still under
378 			 *	debate.  This *is* supported on Solaris,
379 			 *	Linux, and IRIX, but conflicts with `-s'
380 			 *	on NetBSD and maybe some older BSD's.
381 			 */
382 			add_list(&sesslist, optarg);
383 			xkeep_implied = 1;
384 			nselectors++;
385 			break;
386 #endif
387 		case 'T':
388 			if ((optarg = ttyname(STDIN_FILENO)) == NULL)
389 				xo_errx(1, "stdin: not a terminal");
390 			/* FALLTHROUGH */
391 		case 't':
392 			add_list(&ttylist, optarg);
393 			xkeep_implied = 1;
394 			nselectors++;
395 			break;
396 		case 'U':
397 			/* This is what SUSv3 defines as the `-u' option. */
398 			add_list(&uidlist, optarg);
399 			xkeep_implied = 1;
400 			nselectors++;
401 			break;
402 		case 'u':
403 			parsefmt(ufmt, 0);
404 			sortby = SORTCPU;
405 			_fmt = 1;
406 			ufmt[0] = '\0';
407 			break;
408 		case 'v':
409 			parsefmt(vfmt, 0);
410 			sortby = SORTMEM;
411 			_fmt = 1;
412 			vfmt[0] = '\0';
413 			break;
414 		case 'w':
415 			if (wflag)
416 				termwidth = UNLIMITED;
417 			else if (termwidth < 131 && termwidth != UNLIMITED)
418 				termwidth = 131;
419 			wflag++;
420 			break;
421 		case 'X':
422 			/*
423 			 * Note that `-X' and `-x' are not standard "selector"
424 			 * options. For most selector-options, we check *all*
425 			 * processes to see if any are matched by the given
426 			 * value(s).  After we have a set of all the matched
427 			 * processes, then `-X' and `-x' govern whether we
428 			 * modify that *matched* set for processes which do
429 			 * not have a controlling terminal.  `-X' causes
430 			 * those processes to be deleted from the matched
431 			 * set, while `-x' causes them to be kept.
432 			 */
433 			xkeep = 0;
434 			break;
435 		case 'x':
436 			xkeep = 1;
437 			break;
438 		case 'Z':
439 			parsefmt(Zfmt, 0);
440 			Zfmt[0] = '\0';
441 			break;
442 		case '?':
443 		default:
444 			usage();
445 		}
446 	argc -= optind;
447 	argv += optind;
448 
449 	/*
450 	 * If there arguments after processing all the options, attempt
451 	 * to treat them as a list of process ids.
452 	 */
453 	while (*argv) {
454 		if (!isdigitch(**argv))
455 			break;
456 		add_list(&pidlist, *argv);
457 		argv++;
458 	}
459 	if (*argv) {
460 		xo_warnx("illegal argument: %s\n", *argv);
461 		usage();
462 	}
463 	if (optfatal)
464 		exit(1);		/* Error messages already printed. */
465 	if (xkeep < 0)			/* Neither -X nor -x was specified. */
466 		xkeep = xkeep_implied;
467 
468 	kd = kvm_openfiles(nlistf, memf, NULL, O_RDONLY, errbuf);
469 	if (kd == NULL)
470 		xo_errx(1, "%s", errbuf);
471 
472 	if (!_fmt)
473 		parsefmt(dfmt, 0);
474 
475 	if (!all && nselectors == 0) {
476 		uidlist.l.ptr = malloc(sizeof(uid_t));
477 		if (uidlist.l.ptr == NULL)
478 			xo_errx(1, "malloc failed");
479 		nselectors = 1;
480 		uidlist.count = uidlist.maxcount = 1;
481 		*uidlist.l.uids = getuid();
482 	}
483 
484 	/*
485 	 * scan requested variables, noting what structures are needed,
486 	 * and adjusting header widths as appropriate.
487 	 */
488 	scanvars();
489 
490 	/*
491 	 * Get process list.  If the user requested just one selector-
492 	 * option, then kvm_getprocs can be asked to return just those
493 	 * processes.  Otherwise, have it return all processes, and
494 	 * then this routine will search that full list and select the
495 	 * processes which match any of the user's selector-options.
496 	 */
497 	what = showthreads != 0 ? KERN_PROC_ALL : KERN_PROC_PROC;
498 	flag = 0;
499 	if (nselectors == 1) {
500 		if (gidlist.count == 1) {
501 			what = KERN_PROC_RGID | showthreads;
502 			flag = *gidlist.l.gids;
503 			nselectors = 0;
504 		} else if (pgrplist.count == 1) {
505 			what = KERN_PROC_PGRP | showthreads;
506 			flag = *pgrplist.l.pids;
507 			nselectors = 0;
508 		} else if (pidlist.count == 1 && directions == NONE) {
509 			what = KERN_PROC_PID | showthreads;
510 			flag = *pidlist.l.pids;
511 			nselectors = 0;
512 		} else if (ruidlist.count == 1) {
513 			what = KERN_PROC_RUID | showthreads;
514 			flag = *ruidlist.l.uids;
515 			nselectors = 0;
516 		} else if (sesslist.count == 1) {
517 			what = KERN_PROC_SESSION | showthreads;
518 			flag = *sesslist.l.pids;
519 			nselectors = 0;
520 		} else if (ttylist.count == 1) {
521 			what = KERN_PROC_TTY | showthreads;
522 			flag = *ttylist.l.ttys;
523 			nselectors = 0;
524 		} else if (uidlist.count == 1) {
525 			what = KERN_PROC_UID | showthreads;
526 			flag = *uidlist.l.uids;
527 			nselectors = 0;
528 		}
529 	}
530 
531 	/*
532 	 * select procs
533 	 */
534 	nentries = -1;
535 	kp = kvm_getprocs(kd, what, flag, &nentries);
536 	/*
537 	 * Ignore ESRCH to preserve behaviour of "ps -p nonexistent-pid"
538 	 * not reporting an error.
539 	 */
540 	if ((kp == NULL && errno != ESRCH) || (kp != NULL && nentries < 0))
541 		xo_errx(1, "%s", kvm_geterr(kd));
542 	nkept = 0;
543 	pid_count.initial = pidlist.count;
544 	if (directions & DOWN)
545 		for (elem = 0; elem < pidlist.count; elem++)
546 			for (i = 0; i < nentries; i++) {
547 				if (kp[i].ki_ppid == kp[i].ki_pid)
548 					continue;
549 				if (kp[i].ki_ppid == pidlist.l.pids[elem]) {
550 					if (pidlist.count >= pidlist.maxcount)
551 						expand_list(&pidlist);
552 					pidlist.l.pids[pidlist.count++] = kp[i].ki_pid;
553 				}
554 			}
555 	pid_count.traversed = pidlist.count;
556 	if (directions & UP)
557 		for (elem = 0; elem < pidlist.count; elem++) {
558 			if (elem >= pid_count.initial && elem < pid_count.traversed)
559 				continue;
560 			for (i = 0; i < nentries; i++) {
561 				if (kp[i].ki_ppid == kp[i].ki_pid)
562 					continue;
563 				if (kp[i].ki_pid == pidlist.l.pids[elem]) {
564 					if (pidlist.count >= pidlist.maxcount)
565 						expand_list(&pidlist);
566 					pidlist.l.pids[pidlist.count++] = kp[i].ki_ppid;
567 				}
568 			}
569 		}
570 	if (nentries > 0) {
571 		if ((kinfo = malloc(nentries * sizeof(*kinfo))) == NULL)
572 			xo_errx(1, "malloc failed");
573 		for (i = nentries; --i >= 0; ++kp) {
574 			/*
575 			 * If the user specified multiple selection-criteria,
576 			 * then keep any process matched by the inclusive OR
577 			 * of all the selection-criteria given.
578 			 */
579 			if (pidlist.count > 0) {
580 				for (elem = 0; elem < pidlist.count; elem++)
581 					if (kp->ki_pid == pidlist.l.pids[elem])
582 						goto keepit;
583 			}
584 			/*
585 			 * Note that we had to process pidlist before
586 			 * filtering out processes which do not have
587 			 * a controlling terminal.
588 			 */
589 			if (xkeep == 0) {
590 				if ((kp->ki_tdev == NODEV ||
591 				    (kp->ki_flag & P_CONTROLT) == 0))
592 					continue;
593 			}
594 			if (nselectors == 0)
595 				goto keepit;
596 			if (gidlist.count > 0) {
597 				for (elem = 0; elem < gidlist.count; elem++)
598 					if (kp->ki_rgid == gidlist.l.gids[elem])
599 						goto keepit;
600 			}
601 			if (jidlist.count > 0) {
602 				for (elem = 0; elem < jidlist.count; elem++)
603 					if (kp->ki_jid == jidlist.l.jids[elem])
604 						goto keepit;
605 			}
606 			if (pgrplist.count > 0) {
607 				for (elem = 0; elem < pgrplist.count; elem++)
608 					if (kp->ki_pgid ==
609 					    pgrplist.l.pids[elem])
610 						goto keepit;
611 			}
612 			if (ruidlist.count > 0) {
613 				for (elem = 0; elem < ruidlist.count; elem++)
614 					if (kp->ki_ruid ==
615 					    ruidlist.l.uids[elem])
616 						goto keepit;
617 			}
618 			if (sesslist.count > 0) {
619 				for (elem = 0; elem < sesslist.count; elem++)
620 					if (kp->ki_sid == sesslist.l.pids[elem])
621 						goto keepit;
622 			}
623 			if (ttylist.count > 0) {
624 				for (elem = 0; elem < ttylist.count; elem++)
625 					if (kp->ki_tdev == ttylist.l.ttys[elem])
626 						goto keepit;
627 			}
628 			if (uidlist.count > 0) {
629 				for (elem = 0; elem < uidlist.count; elem++)
630 					if (kp->ki_uid == uidlist.l.uids[elem])
631 						goto keepit;
632 			}
633 			/*
634 			 * This process did not match any of the user's
635 			 * selector-options, so skip the process.
636 			 */
637 			continue;
638 
639 		keepit:
640 			next_KINFO = &kinfo[nkept];
641 			next_KINFO->ki_p = kp;
642 			next_KINFO->ki_d.level = 0;
643 			next_KINFO->ki_d.prefix = NULL;
644 			next_KINFO->ki_pcpu = getpcpu(next_KINFO);
645 			if (sortby == SORTMEM)
646 				next_KINFO->ki_memsize = kp->ki_tsize +
647 				    kp->ki_dsize + kp->ki_ssize;
648 			if (needuser)
649 				saveuser(next_KINFO);
650 			nkept++;
651 		}
652 	}
653 
654 	sizevars();
655 
656 	if (nkept == 0) {
657 		printheader();
658 		xo_finish();
659 		exit(1);
660 	}
661 
662 	/*
663 	 * sort proc list
664 	 */
665 	qsort(kinfo, nkept, sizeof(KINFO), pscomp);
666 
667 	/*
668 	 * We want things in descendant order
669 	 */
670 	if (descendancy)
671 		descendant_sort(kinfo, nkept);
672 
673 
674 	/*
675 	 * Prepare formatted output.
676 	 */
677 	for (i = 0; i < nkept; i++)
678 		format_output(&kinfo[i]);
679 
680 	/*
681 	 * Print header.
682 	 */
683 	xo_open_container("process-information");
684 	printheader();
685 	if (xo_get_style(NULL) != XO_STYLE_TEXT)
686 		termwidth = UNLIMITED;
687 
688 	/*
689 	 * Output formatted lines.
690 	 */
691 	xo_open_list("process");
692 	for (i = lineno = 0; i < nkept; i++) {
693 		linelen = 0;
694 		xo_open_instance("process");
695 		STAILQ_FOREACH(vent, &varlist, next_ve) {
696 			ks = STAILQ_FIRST(&kinfo[i].ki_ks);
697 			STAILQ_REMOVE_HEAD(&kinfo[i].ki_ks, ks_next);
698 			/* Truncate rightmost column if necessary.  */
699 			fwidthmax = _POSIX2_LINE_MAX;
700 			if (STAILQ_NEXT(vent, next_ve) == NULL &&
701 			   termwidth != UNLIMITED && ks->ks_str != NULL) {
702 				left = termwidth - linelen;
703 				if (left > 0 && left < (int)strlen(ks->ks_str))
704 					fwidthmax = left;
705 			}
706 
707 			str = ks->ks_str;
708 			if (str == NULL)
709 				str = "-";
710 			/* No padding for the last column, if it's LJUST. */
711 			fwidthmin = (xo_get_style(NULL) != XO_STYLE_TEXT ||
712 			    (STAILQ_NEXT(vent, next_ve) == NULL &&
713 			    (vent->var->flag & LJUST))) ? 0 : vent->var->width;
714 			snprintf(fmtbuf, sizeof(fmtbuf), "{:%s/%%%s%d..%dhs}",
715 			    vent->var->field ? vent->var->field : vent->var->name,
716 			    (vent->var->flag & LJUST) ? "-" : "",
717 			    fwidthmin, fwidthmax);
718 			xo_emit(fmtbuf, str);
719 			linelen += fwidthmin;
720 
721 			if (ks->ks_str != NULL) {
722 				free(ks->ks_str);
723 				ks->ks_str = NULL;
724 			}
725 			free(ks);
726 			ks = NULL;
727 
728 			if (STAILQ_NEXT(vent, next_ve) != NULL) {
729 				xo_emit("{P: }");
730 				linelen++;
731 			}
732 		}
733 	        xo_emit("\n");
734 		xo_close_instance("process");
735 		if (prtheader && lineno++ == prtheader - 4) {
736 			xo_emit("\n");
737 			printheader();
738 			lineno = 0;
739 		}
740 	}
741 	xo_close_list("process");
742 	xo_close_container("process-information");
743 	xo_finish();
744 
745 	free_list(&gidlist);
746 	free_list(&jidlist);
747 	free_list(&pidlist);
748 	free_list(&pgrplist);
749 	free_list(&ruidlist);
750 	free_list(&sesslist);
751 	free_list(&ttylist);
752 	free_list(&uidlist);
753 	for (i = 0; i < nkept; i++)
754 		free(kinfo[i].ki_d.prefix);
755 	free(kinfo);
756 
757 	exit(eval);
758 }
759 
760 static int
761 addelem_gid(struct listinfo *inf, const char *elem)
762 {
763 	struct group *grp;
764 	const char *nameorID;
765 	char *endp;
766 	u_long bigtemp;
767 
768 	if (*elem == '\0' || strlen(elem) >= MAXLOGNAME) {
769 		if (*elem == '\0')
770 			xo_warnx("Invalid (zero-length) %s name", inf->lname);
771 		else
772 			xo_warnx("%s name too long: %s", inf->lname, elem);
773 		optfatal = 1;
774 		return (0);		/* Do not add this value. */
775 	}
776 
777 	/*
778 	 * SUSv3 states that `ps -G grouplist' should match "real-group
779 	 * ID numbers", and does not mention group-names.  I do want to
780 	 * also support group-names, so this tries for a group-id first,
781 	 * and only tries for a name if that doesn't work.  This is the
782 	 * opposite order of what is done in addelem_uid(), but in
783 	 * practice the order would only matter for group-names which
784 	 * are all-numeric.
785 	 */
786 	grp = NULL;
787 	nameorID = "named";
788 	errno = 0;
789 	bigtemp = strtoul(elem, &endp, 10);
790 	if (errno == 0 && *endp == '\0' && bigtemp <= GID_MAX) {
791 		nameorID = "name or ID matches";
792 		grp = getgrgid((gid_t)bigtemp);
793 	}
794 	if (grp == NULL)
795 		grp = getgrnam(elem);
796 	if (grp == NULL) {
797 		xo_warnx("No %s %s '%s'", inf->lname, nameorID, elem);
798 		optfatal = 1;
799 		return (0);
800 	}
801 	if (inf->count >= inf->maxcount)
802 		expand_list(inf);
803 	inf->l.gids[(inf->count)++] = grp->gr_gid;
804 	return (1);
805 }
806 
807 static int
808 addelem_jid(struct listinfo *inf, const char *elem)
809 {
810 	int tempid;
811 
812 	if (*elem == '\0') {
813 		warnx("Invalid (zero-length) jail id");
814 		optfatal = 1;
815 		return (0);		/* Do not add this value. */
816 	}
817 
818 	tempid = jail_getid(elem);
819 	if (tempid < 0) {
820 		warnx("Invalid %s: %s", inf->lname, elem);
821 		optfatal = 1;
822 		return (0);
823 	}
824 
825 	if (inf->count >= inf->maxcount)
826 		expand_list(inf);
827 	inf->l.jids[(inf->count)++] = tempid;
828 	return (1);
829 }
830 
831 static int
832 addelem_pid(struct listinfo *inf, const char *elem)
833 {
834 	char *endp;
835 	long tempid;
836 
837 	if (*elem == '\0') {
838 		xo_warnx("Invalid (zero-length) process id");
839 		optfatal = 1;
840 		return (0);		/* Do not add this value. */
841 	}
842 
843 	errno = 0;
844 	tempid = strtol(elem, &endp, 10);
845 	if (*endp != '\0' || tempid < 0 || elem == endp) {
846 		xo_warnx("Invalid %s: %s", inf->lname, elem);
847 		errno = ERANGE;
848 	} else if (errno != 0 || tempid > pid_max) {
849 		xo_warnx("%s too large: %s", inf->lname, elem);
850 		errno = ERANGE;
851 	}
852 	if (errno == ERANGE) {
853 		optfatal = 1;
854 		return (0);
855 	}
856 	if (inf->count >= inf->maxcount)
857 		expand_list(inf);
858 	inf->l.pids[(inf->count)++] = tempid;
859 	return (1);
860 }
861 
862 /*-
863  * The user can specify a device via one of three formats:
864  *     1) fully qualified, e.g.:     /dev/ttyp0 /dev/console	/dev/pts/0
865  *     2) missing "/dev", e.g.:      ttyp0      console		pts/0
866  *     3) two-letters, e.g.:         p0         co		0
867  *        (matching letters that would be seen in the "TT" column)
868  */
869 static int
870 addelem_tty(struct listinfo *inf, const char *elem)
871 {
872 	const char *ttypath;
873 	struct stat sb;
874 	char pathbuf[PATH_MAX], pathbuf2[PATH_MAX], pathbuf3[PATH_MAX];
875 
876 	ttypath = NULL;
877 	pathbuf2[0] = '\0';
878 	pathbuf3[0] = '\0';
879 	switch (*elem) {
880 	case '/':
881 		ttypath = elem;
882 		break;
883 	case 'c':
884 		if (strcmp(elem, "co") == 0) {
885 			ttypath = _PATH_CONSOLE;
886 			break;
887 		}
888 		/* FALLTHROUGH */
889 	default:
890 		strlcpy(pathbuf, _PATH_DEV, sizeof(pathbuf));
891 		strlcat(pathbuf, elem, sizeof(pathbuf));
892 		ttypath = pathbuf;
893 		if (strncmp(pathbuf, _PATH_TTY, strlen(_PATH_TTY)) == 0)
894 			break;
895 		if (strncmp(pathbuf, _PATH_PTS, strlen(_PATH_PTS)) == 0)
896 			break;
897 		if (strcmp(pathbuf, _PATH_CONSOLE) == 0)
898 			break;
899 		/* Check to see if /dev/tty${elem} exists */
900 		strlcpy(pathbuf2, _PATH_TTY, sizeof(pathbuf2));
901 		strlcat(pathbuf2, elem, sizeof(pathbuf2));
902 		if (stat(pathbuf2, &sb) == 0 && S_ISCHR(sb.st_mode)) {
903 			/* No need to repeat stat() && S_ISCHR() checks */
904 			ttypath = NULL;
905 			break;
906 		}
907 		/* Check to see if /dev/pts/${elem} exists */
908 		strlcpy(pathbuf3, _PATH_PTS, sizeof(pathbuf3));
909 		strlcat(pathbuf3, elem, sizeof(pathbuf3));
910 		if (stat(pathbuf3, &sb) == 0 && S_ISCHR(sb.st_mode)) {
911 			/* No need to repeat stat() && S_ISCHR() checks */
912 			ttypath = NULL;
913 			break;
914 		}
915 		break;
916 	}
917 	if (ttypath) {
918 		if (stat(ttypath, &sb) == -1) {
919 			if (pathbuf3[0] != '\0')
920 				xo_warn("%s, %s, and %s", pathbuf3, pathbuf2,
921 				    ttypath);
922 			else
923 				xo_warn("%s", ttypath);
924 			optfatal = 1;
925 			return (0);
926 		}
927 		if (!S_ISCHR(sb.st_mode)) {
928 			if (pathbuf3[0] != '\0')
929 				xo_warnx("%s, %s, and %s: Not a terminal",
930 				    pathbuf3, pathbuf2, ttypath);
931 			else
932 				xo_warnx("%s: Not a terminal", ttypath);
933 			optfatal = 1;
934 			return (0);
935 		}
936 	}
937 	if (inf->count >= inf->maxcount)
938 		expand_list(inf);
939 	inf->l.ttys[(inf->count)++] = sb.st_rdev;
940 	return (1);
941 }
942 
943 static int
944 addelem_uid(struct listinfo *inf, const char *elem)
945 {
946 	struct passwd *pwd;
947 	char *endp;
948 	u_long bigtemp;
949 
950 	if (*elem == '\0' || strlen(elem) >= MAXLOGNAME) {
951 		if (*elem == '\0')
952 			xo_warnx("Invalid (zero-length) %s name", inf->lname);
953 		else
954 			xo_warnx("%s name too long: %s", inf->lname, elem);
955 		optfatal = 1;
956 		return (0);		/* Do not add this value. */
957 	}
958 
959 	pwd = getpwnam(elem);
960 	if (pwd == NULL) {
961 		errno = 0;
962 		bigtemp = strtoul(elem, &endp, 10);
963 		if (errno != 0 || *endp != '\0' || bigtemp > UID_MAX)
964 			xo_warnx("No %s named '%s'", inf->lname, elem);
965 		else {
966 			/* The string is all digits, so it might be a userID. */
967 			pwd = getpwuid((uid_t)bigtemp);
968 			if (pwd == NULL)
969 				xo_warnx("No %s name or ID matches '%s'",
970 				    inf->lname, elem);
971 		}
972 	}
973 	if (pwd == NULL) {
974 		/*
975 		 * These used to be treated as minor warnings (and the
976 		 * option was simply ignored), but now they are fatal
977 		 * errors (and the command will be aborted).
978 		 */
979 		optfatal = 1;
980 		return (0);
981 	}
982 	if (inf->count >= inf->maxcount)
983 		expand_list(inf);
984 	inf->l.uids[(inf->count)++] = pwd->pw_uid;
985 	return (1);
986 }
987 
988 static void
989 add_list(struct listinfo *inf, const char *argp)
990 {
991 	const char *savep;
992 	char *cp, *endp;
993 	int toolong;
994 	char elemcopy[PATH_MAX];
995 
996 	if (*argp == '\0')
997 		inf->addelem(inf, argp);
998 	while (*argp != '\0') {
999 		while (*argp != '\0' && strchr(W_SEP, *argp) != NULL)
1000 			argp++;
1001 		savep = argp;
1002 		toolong = 0;
1003 		cp = elemcopy;
1004 		if (strchr(T_SEP, *argp) == NULL) {
1005 			endp = elemcopy + sizeof(elemcopy) - 1;
1006 			while (*argp != '\0' && cp <= endp &&
1007 			    strchr(W_SEP T_SEP, *argp) == NULL)
1008 				*cp++ = *argp++;
1009 			if (cp > endp)
1010 				toolong = 1;
1011 		}
1012 		if (!toolong) {
1013 			*cp = '\0';
1014 			/*
1015 			 * Add this single element to the given list.
1016 			 */
1017 			inf->addelem(inf, elemcopy);
1018 		} else {
1019 			/*
1020 			 * The string is too long to copy.  Find the end
1021 			 * of the string to print out the warning message.
1022 			 */
1023 			while (*argp != '\0' && strchr(W_SEP T_SEP,
1024 			    *argp) == NULL)
1025 				argp++;
1026 			xo_warnx("Value too long: %.*s", (int)(argp - savep),
1027 			    savep);
1028 			optfatal = 1;
1029 		}
1030 		/*
1031 		 * Skip over any number of trailing whitespace characters,
1032 		 * but only one (at most) trailing element-terminating
1033 		 * character.
1034 		 */
1035 		while (*argp != '\0' && strchr(W_SEP, *argp) != NULL)
1036 			argp++;
1037 		if (*argp != '\0' && strchr(T_SEP, *argp) != NULL) {
1038 			argp++;
1039 			/* Catch case where string ended with a comma. */
1040 			if (*argp == '\0')
1041 				inf->addelem(inf, argp);
1042 		}
1043 	}
1044 }
1045 
1046 static void
1047 descendant_sort(KINFO *ki, int items)
1048 {
1049 	int dst, lvl, maxlvl, n, ndst, nsrc, siblings, src;
1050 	unsigned char *path;
1051 	KINFO kn;
1052 
1053 	/*
1054 	 * First, sort the entries by descendancy, tracking the descendancy
1055 	 * depth in the ki_d.level field.
1056 	 */
1057 	src = 0;
1058 	maxlvl = 0;
1059 	while (src < items) {
1060 		if (ki[src].ki_d.level) {
1061 			src++;
1062 			continue;
1063 		}
1064 		for (nsrc = 1; src + nsrc < items; nsrc++)
1065 			if (!ki[src + nsrc].ki_d.level)
1066 				break;
1067 
1068 		for (dst = 0; dst < items; dst++) {
1069 			if (ki[dst].ki_p->ki_pid == ki[src].ki_p->ki_pid)
1070 				continue;
1071 			if (ki[dst].ki_p->ki_pid == ki[src].ki_p->ki_ppid)
1072 				break;
1073 		}
1074 
1075 		if (dst == items) {
1076 			src += nsrc;
1077 			continue;
1078 		}
1079 
1080 		for (ndst = 1; dst + ndst < items; ndst++)
1081 			if (ki[dst + ndst].ki_d.level <= ki[dst].ki_d.level)
1082 				break;
1083 
1084 		for (n = src; n < src + nsrc; n++) {
1085 			ki[n].ki_d.level += ki[dst].ki_d.level + 1;
1086 			if (maxlvl < ki[n].ki_d.level)
1087 				maxlvl = ki[n].ki_d.level;
1088 		}
1089 
1090 		while (nsrc) {
1091 			if (src < dst) {
1092 				kn = ki[src];
1093 				memmove(ki + src, ki + src + 1,
1094 				    (dst - src + ndst - 1) * sizeof *ki);
1095 				ki[dst + ndst - 1] = kn;
1096 				nsrc--;
1097 				dst--;
1098 				ndst++;
1099 			} else if (src != dst + ndst) {
1100 				kn = ki[src];
1101 				memmove(ki + dst + ndst + 1, ki + dst + ndst,
1102 				    (src - dst - ndst) * sizeof *ki);
1103 				ki[dst + ndst] = kn;
1104 				ndst++;
1105 				nsrc--;
1106 				src++;
1107 			} else {
1108 				ndst += nsrc;
1109 				src += nsrc;
1110 				nsrc = 0;
1111 			}
1112 		}
1113 	}
1114 
1115 	/*
1116 	 * Now populate ki_d.prefix (instead of ki_d.level) with the command
1117 	 * prefix used to show descendancies.
1118 	 */
1119 	path = calloc((maxlvl + 7) / 8, sizeof(unsigned char));
1120 	for (src = 0; src < items; src++) {
1121 		if ((lvl = ki[src].ki_d.level) == 0) {
1122 			ki[src].ki_d.prefix = NULL;
1123 			continue;
1124 		}
1125 		if ((ki[src].ki_d.prefix = malloc(lvl * 2 + 1)) == NULL)
1126 			xo_errx(1, "malloc failed");
1127 		for (n = 0; n < lvl - 2; n++) {
1128 			ki[src].ki_d.prefix[n * 2] =
1129 			    path[n / 8] & 1 << (n % 8) ? '|' : ' ';
1130 			ki[src].ki_d.prefix[n * 2 + 1] = ' ';
1131 		}
1132 		if (n == lvl - 2) {
1133 			/* Have I any more siblings? */
1134 			for (siblings = 0, dst = src + 1; dst < items; dst++) {
1135 				if (ki[dst].ki_d.level > lvl)
1136 					continue;
1137 				if (ki[dst].ki_d.level == lvl)
1138 					siblings = 1;
1139 				break;
1140 			}
1141 			if (siblings)
1142 				path[n / 8] |= 1 << (n % 8);
1143 			else
1144 				path[n / 8] &= ~(1 << (n % 8));
1145 			ki[src].ki_d.prefix[n * 2] = siblings ? '|' : '`';
1146 			ki[src].ki_d.prefix[n * 2 + 1] = '-';
1147 			n++;
1148 		}
1149 		strcpy(ki[src].ki_d.prefix + n * 2, "- ");
1150 	}
1151 	free(path);
1152 }
1153 
1154 static void *
1155 expand_list(struct listinfo *inf)
1156 {
1157 	void *newlist;
1158 	int newmax;
1159 
1160 	newmax = (inf->maxcount + 1) << 1;
1161 	newlist = realloc(inf->l.ptr, newmax * inf->elemsize);
1162 	if (newlist == NULL) {
1163 		free(inf->l.ptr);
1164 		xo_errx(1, "realloc to %d %ss failed", newmax, inf->lname);
1165 	}
1166 	inf->maxcount = newmax;
1167 	inf->l.ptr = newlist;
1168 
1169 	return (newlist);
1170 }
1171 
1172 static void
1173 free_list(struct listinfo *inf)
1174 {
1175 
1176 	inf->count = inf->elemsize = inf->maxcount = 0;
1177 	if (inf->l.ptr != NULL)
1178 		free(inf->l.ptr);
1179 	inf->addelem = NULL;
1180 	inf->lname = NULL;
1181 	inf->l.ptr = NULL;
1182 }
1183 
1184 static void
1185 init_list(struct listinfo *inf, addelem_rtn artn, int elemsize,
1186     const char *lname)
1187 {
1188 
1189 	inf->count = inf->maxcount = 0;
1190 	inf->elemsize = elemsize;
1191 	inf->addelem = artn;
1192 	inf->lname = lname;
1193 	inf->l.ptr = NULL;
1194 }
1195 
1196 VARENT *
1197 find_varentry(VAR *v)
1198 {
1199 	struct varent *vent;
1200 
1201 	STAILQ_FOREACH(vent, &varlist, next_ve) {
1202 		if (strcmp(vent->var->name, v->name) == 0)
1203 			return vent;
1204 	}
1205 	return NULL;
1206 }
1207 
1208 static void
1209 scanvars(void)
1210 {
1211 	struct varent *vent;
1212 	VAR *v;
1213 
1214 	STAILQ_FOREACH(vent, &varlist, next_ve) {
1215 		v = vent->var;
1216 		if (v->flag & USER)
1217 			needuser = 1;
1218 		if (v->flag & COMM)
1219 			needcomm = 1;
1220 	}
1221 }
1222 
1223 static void
1224 format_output(KINFO *ki)
1225 {
1226 	struct varent *vent;
1227 	VAR *v;
1228 	KINFO_STR *ks;
1229 	char *str;
1230 	int len;
1231 
1232 	STAILQ_INIT(&ki->ki_ks);
1233 	STAILQ_FOREACH(vent, &varlist, next_ve) {
1234 		v = vent->var;
1235 		str = (v->oproc)(ki, vent);
1236 		ks = malloc(sizeof(*ks));
1237 		if (ks == NULL)
1238 			xo_errx(1, "malloc failed");
1239 		ks->ks_str = str;
1240 		STAILQ_INSERT_TAIL(&ki->ki_ks, ks, ks_next);
1241 		if (str != NULL) {
1242 			len = strlen(str);
1243 		} else
1244 			len = 1; /* "-" */
1245 		if (v->width < len)
1246 			v->width = len;
1247 	}
1248 }
1249 
1250 static void
1251 sizevars(void)
1252 {
1253 	struct varent *vent;
1254 	VAR *v;
1255 	int i;
1256 
1257 	STAILQ_FOREACH(vent, &varlist, next_ve) {
1258 		v = vent->var;
1259 		i = strlen(vent->header);
1260 		if (v->width < i)
1261 			v->width = i;
1262 	}
1263 }
1264 
1265 static const char *
1266 fmt(char **(*fn)(kvm_t *, const struct kinfo_proc *, int), KINFO *ki,
1267     char *comm, char *thread, int maxlen)
1268 {
1269 	const char *s;
1270 
1271 	s = fmt_argv((*fn)(kd, ki->ki_p, termwidth), comm,
1272 	    showthreads && ki->ki_p->ki_numthreads > 1 ? thread : NULL, maxlen);
1273 	return (s);
1274 }
1275 
1276 #define UREADOK(ki)	(forceuread || (ki->ki_p->ki_flag & P_INMEM))
1277 
1278 static void
1279 saveuser(KINFO *ki)
1280 {
1281 	char tdname[COMMLEN + 1];
1282 	char *argsp;
1283 
1284 	if (ki->ki_p->ki_flag & P_INMEM) {
1285 		/*
1286 		 * The u-area might be swapped out, and we can't get
1287 		 * at it because we have a crashdump and no swap.
1288 		 * If it's here fill in these fields, otherwise, just
1289 		 * leave them 0.
1290 		 */
1291 		ki->ki_valid = 1;
1292 	} else
1293 		ki->ki_valid = 0;
1294 	/*
1295 	 * save arguments if needed
1296 	 */
1297 	if (needcomm) {
1298 		if (ki->ki_p->ki_stat == SZOMB) {
1299 			ki->ki_args = strdup("<defunct>");
1300 		} else if (UREADOK(ki) || (ki->ki_p->ki_args != NULL)) {
1301 			(void)snprintf(tdname, sizeof(tdname), "%s%s",
1302 			    ki->ki_p->ki_tdname, ki->ki_p->ki_moretdname);
1303 			ki->ki_args = fmt(kvm_getargv, ki,
1304 			    ki->ki_p->ki_comm, tdname, COMMLEN * 2 + 1);
1305 		} else {
1306 			asprintf(&argsp, "(%s)", ki->ki_p->ki_comm);
1307 			ki->ki_args = argsp;
1308 		}
1309 		if (ki->ki_args == NULL)
1310 			xo_errx(1, "malloc failed");
1311 	} else {
1312 		ki->ki_args = NULL;
1313 	}
1314 	if (needenv) {
1315 		if (UREADOK(ki))
1316 			ki->ki_env = fmt(kvm_getenvv, ki,
1317 			    (char *)NULL, (char *)NULL, 0);
1318 		else
1319 			ki->ki_env = strdup("()");
1320 		if (ki->ki_env == NULL)
1321 			xo_errx(1, "malloc failed");
1322 	} else {
1323 		ki->ki_env = NULL;
1324 	}
1325 }
1326 
1327 /* A macro used to improve the readability of pscomp(). */
1328 #define	DIFF_RETURN(a, b, field) do {	\
1329 	if ((a)->field != (b)->field)	\
1330 		return (((a)->field < (b)->field) ? -1 : 1); 	\
1331 } while (0)
1332 
1333 static int
1334 pscomp(const void *a, const void *b)
1335 {
1336 	const KINFO *ka, *kb;
1337 
1338 	ka = a;
1339 	kb = b;
1340 	/* SORTCPU and SORTMEM are sorted in descending order. */
1341 	if (sortby == SORTCPU)
1342 		DIFF_RETURN(kb, ka, ki_pcpu);
1343 	if (sortby == SORTMEM)
1344 		DIFF_RETURN(kb, ka, ki_memsize);
1345 	/*
1346 	 * TTY's are sorted in ascending order, except that all NODEV
1347 	 * processes come before all processes with a device.
1348 	 */
1349 	if (ka->ki_p->ki_tdev != kb->ki_p->ki_tdev) {
1350 		if (ka->ki_p->ki_tdev == NODEV)
1351 			return (-1);
1352 		if (kb->ki_p->ki_tdev == NODEV)
1353 			return (1);
1354 		DIFF_RETURN(ka, kb, ki_p->ki_tdev);
1355 	}
1356 
1357 	/* PID's and TID's (threads) are sorted in ascending order. */
1358 	DIFF_RETURN(ka, kb, ki_p->ki_pid);
1359 	DIFF_RETURN(ka, kb, ki_p->ki_tid);
1360 	return (0);
1361 }
1362 #undef DIFF_RETURN
1363 
1364 /*
1365  * ICK (all for getopt), would rather hide the ugliness
1366  * here than taint the main code.
1367  *
1368  *  ps foo -> ps -foo
1369  *  ps 34 -> ps -p34
1370  *
1371  * The old convention that 't' with no trailing tty arg means the users
1372  * tty, is only supported if argv[1] doesn't begin with a '-'.  This same
1373  * feature is available with the option 'T', which takes no argument.
1374  */
1375 static char *
1376 kludge_oldps_options(const char *optlist, char *origval, const char *nextarg)
1377 {
1378 	size_t len;
1379 	char *argp, *cp, *newopts, *ns, *optp, *pidp;
1380 
1381 	/*
1382 	 * See if the original value includes any option which takes an
1383 	 * argument (and will thus use up the remainder of the string).
1384 	 */
1385 	argp = NULL;
1386 	if (optlist != NULL) {
1387 		for (cp = origval; *cp != '\0'; cp++) {
1388 			optp = strchr(optlist, *cp);
1389 			if ((optp != NULL) && *(optp + 1) == ':') {
1390 				argp = cp;
1391 				break;
1392 			}
1393 		}
1394 	}
1395 	if (argp != NULL && *origval == '-')
1396 		return (origval);
1397 
1398 	/*
1399 	 * if last letter is a 't' flag with no argument (in the context
1400 	 * of the oldps options -- option string NOT starting with a '-' --
1401 	 * then convert to 'T' (meaning *this* terminal, i.e. ttyname(0)).
1402 	 *
1403 	 * However, if a flag accepting a string argument is found earlier
1404 	 * in the option string (including a possible `t' flag), then the
1405 	 * remainder of the string must be the argument to that flag; so
1406 	 * do not modify that argument.  Note that a trailing `t' would
1407 	 * cause argp to be set, if argp was not already set by some
1408 	 * earlier option.
1409 	 */
1410 	len = strlen(origval);
1411 	cp = origval + len - 1;
1412 	pidp = NULL;
1413 	if (*cp == 't' && *origval != '-' && cp == argp) {
1414 		if (nextarg == NULL || *nextarg == '-' || isdigitch(*nextarg))
1415 			*cp = 'T';
1416 	} else if (argp == NULL) {
1417 		/*
1418 		 * The original value did not include any option which takes
1419 		 * an argument (and that would include `p' and `t'), so check
1420 		 * the value for trailing number, or comma-separated list of
1421 		 * numbers, which we will treat as a pid request.
1422 		 */
1423 		if (isdigitch(*cp)) {
1424 			while (cp >= origval && (*cp == ',' || isdigitch(*cp)))
1425 				--cp;
1426 			pidp = cp + 1;
1427 		}
1428 	}
1429 
1430 	/*
1431 	 * If nothing needs to be added to the string, then return
1432 	 * the "original" (although possibly modified) value.
1433 	 */
1434 	if (*origval == '-' && pidp == NULL)
1435 		return (origval);
1436 
1437 	/*
1438 	 * Create a copy of the string to add '-' and/or 'p' to the
1439 	 * original value.
1440 	 */
1441 	if ((newopts = ns = malloc(len + 3)) == NULL)
1442 		xo_errx(1, "malloc failed");
1443 
1444 	if (*origval != '-')
1445 		*ns++ = '-';	/* add option flag */
1446 
1447 	if (pidp == NULL)
1448 		strcpy(ns, origval);
1449 	else {
1450 		/*
1451 		 * Copy everything before the pid string, add the `p',
1452 		 * and then copy the pid string.
1453 		 */
1454 		len = pidp - origval;
1455 		memcpy(ns, origval, len);
1456 		ns += len;
1457 		*ns++ = 'p';
1458 		strcpy(ns, pidp);
1459 	}
1460 
1461 	return (newopts);
1462 }
1463 
1464 static void
1465 pidmax_init(void)
1466 {
1467 	size_t intsize;
1468 
1469 	intsize = sizeof(pid_max);
1470 	if (sysctlbyname("kern.pid_max", &pid_max, &intsize, NULL, 0) < 0) {
1471 		xo_warn("unable to read kern.pid_max");
1472 		pid_max = 99999;
1473 	}
1474 }
1475 
1476 static void __dead2
1477 usage(void)
1478 {
1479 #define	SINGLE_OPTS	"[-aCcde" OPT_LAZY_f "HhjlmrSTuvwXxZ]"
1480 
1481 	(void)xo_error("%s\n%s\n%s\n%s\n%s\n",
1482 	    "usage: ps [--libxo] " SINGLE_OPTS " [-O fmt | -o fmt]",
1483 	    "          [-G gid[,gid...]] [-J jid[,jid...]] [-M core] [-N system]",
1484 	    "          [-p pid[,pid...]] [-t tty[,tty...]] [-U user[,user...]]",
1485 	    "          [-D up | down | both]",
1486 	    "       ps [--libxo] -L");
1487 	exit(1);
1488 }
1489