xref: /freebsd/bin/ps/ps.c (revision 40a8ac8f62b535d30349faf28cf47106b7041b83)
1 /*-
2  * Copyright (c) 1990, 1993, 1994
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 4. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  * ------+---------+---------+-------- + --------+---------+---------+---------*
29  * Copyright (c) 2004  - Garance Alistair Drosehn <gad@FreeBSD.org>.
30  * All rights reserved.
31  *
32  * Significant modifications made to bring `ps' options somewhat closer
33  * to the standard for `ps' as described in SingleUnixSpec-v3.
34  * ------+---------+---------+-------- + --------+---------+---------+---------*
35  */
36 
37 #ifndef lint
38 static const char copyright[] =
39 "@(#) Copyright (c) 1990, 1993, 1994\n\
40 	The Regents of the University of California.  All rights reserved.\n";
41 #endif /* not lint */
42 
43 #if 0
44 #ifndef lint
45 static char sccsid[] = "@(#)ps.c	8.4 (Berkeley) 4/2/94";
46 #endif /* not lint */
47 #endif
48 
49 #include <sys/cdefs.h>
50 __FBSDID("$FreeBSD$");
51 
52 #include <sys/param.h>
53 #include <sys/jail.h>
54 #include <sys/proc.h>
55 #include <sys/user.h>
56 #include <sys/stat.h>
57 #include <sys/ioctl.h>
58 #include <sys/sysctl.h>
59 #include <sys/mount.h>
60 
61 #include <ctype.h>
62 #include <err.h>
63 #include <errno.h>
64 #include <fcntl.h>
65 #include <grp.h>
66 #include <jail.h>
67 #include <kvm.h>
68 #include <limits.h>
69 #include <locale.h>
70 #include <paths.h>
71 #include <pwd.h>
72 #include <stdio.h>
73 #include <stdlib.h>
74 #include <string.h>
75 #include <unistd.h>
76 
77 #include "ps.h"
78 
79 #define	_PATH_PTS	"/dev/pts/"
80 
81 #define	W_SEP	" \t"		/* "Whitespace" list separators */
82 #define	T_SEP	","		/* "Terminate-element" list separators */
83 
84 #ifdef LAZY_PS
85 #define	DEF_UREAD	0
86 #define	OPT_LAZY_f	"f"
87 #else
88 #define	DEF_UREAD	1	/* Always do the more-expensive read. */
89 #define	OPT_LAZY_f		/* I.e., the `-f' option is not added. */
90 #endif
91 
92 /*
93  * isdigit takes an `int', but expects values in the range of unsigned char.
94  * This wrapper ensures that values from a 'char' end up in the correct range.
95  */
96 #define	isdigitch(Anychar) isdigit((u_char)(Anychar))
97 
98 int	 cflag;			/* -c */
99 int	 eval;			/* Exit value */
100 time_t	 now;			/* Current time(3) value */
101 int	 rawcpu;		/* -C */
102 int	 sumrusage;		/* -S */
103 int	 termwidth;		/* Width of the screen (0 == infinity). */
104 int	 showthreads;		/* will threads be shown? */
105 
106 struct velisthead varlist = STAILQ_HEAD_INITIALIZER(varlist);
107 
108 static int	 forceuread = DEF_UREAD; /* Do extra work to get u-area. */
109 static kvm_t	*kd;
110 static int	 needcomm;	/* -o "command" */
111 static int	 needenv;	/* -e */
112 static int	 needuser;	/* -o "user" */
113 static int	 optfatal;	/* Fatal error parsing some list-option. */
114 static int	 pid_max;	/* kern.max_pid */
115 
116 static enum sort { DEFAULT, SORTMEM, SORTCPU } sortby = DEFAULT;
117 
118 struct listinfo;
119 typedef	int	addelem_rtn(struct listinfo *_inf, const char *_elem);
120 
121 struct listinfo {
122 	int		 count;
123 	int		 maxcount;
124 	int		 elemsize;
125 	addelem_rtn	*addelem;
126 	const char	*lname;
127 	union {
128 		gid_t	*gids;
129 		int	*jids;
130 		pid_t	*pids;
131 		dev_t	*ttys;
132 		uid_t	*uids;
133 		void	*ptr;
134 	} l;
135 };
136 
137 static int	 addelem_gid(struct listinfo *, const char *);
138 static int	 addelem_jid(struct listinfo *, const char *);
139 static int	 addelem_pid(struct listinfo *, const char *);
140 static int	 addelem_tty(struct listinfo *, const char *);
141 static int	 addelem_uid(struct listinfo *, const char *);
142 static void	 add_list(struct listinfo *, const char *);
143 static void	 descendant_sort(KINFO *, int);
144 static void	 format_output(KINFO *);
145 static void	*expand_list(struct listinfo *);
146 static const char *
147 		 fmt(char **(*)(kvm_t *, const struct kinfo_proc *, int),
148 		    KINFO *, char *, char *, int);
149 static void	 free_list(struct listinfo *);
150 static void	 init_list(struct listinfo *, addelem_rtn, int, const char *);
151 static char	*kludge_oldps_options(const char *, char *, const char *);
152 static int	 pscomp(const void *, const void *);
153 static void	 saveuser(KINFO *);
154 static void	 scanvars(void);
155 static void	 sizevars(void);
156 static void	 pidmax_init(void);
157 static void	 usage(void);
158 
159 static char dfmt[] = "pid,tt,state,time,command";
160 static char jfmt[] = "user,pid,ppid,pgid,sid,jobc,state,tt,time,command";
161 static char lfmt[] = "uid,pid,ppid,cpu,pri,nice,vsz,rss,mwchan,state,"
162 			"tt,time,command";
163 static char   o1[] = "pid";
164 static char   o2[] = "tt,state,time,command";
165 static char ufmt[] = "user,pid,%cpu,%mem,vsz,rss,tt,state,start,time,command";
166 static char vfmt[] = "pid,state,time,sl,re,pagein,vsz,rss,lim,tsiz,"
167 			"%cpu,%mem,command";
168 static char Zfmt[] = "label";
169 
170 #define	PS_ARGS	"AaCcde" OPT_LAZY_f "G:gHhjJ:LlM:mN:O:o:p:rSTt:U:uvwXxZ"
171 
172 int
173 main(int argc, char *argv[])
174 {
175 	struct listinfo gidlist, jidlist, pgrplist, pidlist;
176 	struct listinfo ruidlist, sesslist, ttylist, uidlist;
177 	struct kinfo_proc *kp;
178 	KINFO *kinfo = NULL, *next_KINFO;
179 	KINFO_STR *ks;
180 	struct varent *vent;
181 	struct winsize ws;
182 	const char *nlistf, *memf, *fmtstr, *str;
183 	char *cols;
184 	int all, ch, elem, flag, _fmt, i, lineno, linelen, left;
185 	int descendancy, nentries, nkept, nselectors;
186 	int prtheader, wflag, what, xkeep, xkeep_implied;
187 	char errbuf[_POSIX2_LINE_MAX];
188 
189 	(void) setlocale(LC_ALL, "");
190 	time(&now);			/* Used by routines in print.c. */
191 
192 	if ((cols = getenv("COLUMNS")) != NULL && *cols != '\0')
193 		termwidth = atoi(cols);
194 	else if ((ioctl(STDOUT_FILENO, TIOCGWINSZ, (char *)&ws) == -1 &&
195 	     ioctl(STDERR_FILENO, TIOCGWINSZ, (char *)&ws) == -1 &&
196 	     ioctl(STDIN_FILENO,  TIOCGWINSZ, (char *)&ws) == -1) ||
197 	     ws.ws_col == 0)
198 		termwidth = 79;
199 	else
200 		termwidth = ws.ws_col - 1;
201 
202 	/*
203 	 * Hide a number of option-processing kludges in a separate routine,
204 	 * to support some historical BSD behaviors, such as `ps axu'.
205 	 */
206 	if (argc > 1)
207 		argv[1] = kludge_oldps_options(PS_ARGS, argv[1], argv[2]);
208 
209 	pidmax_init();
210 
211 	all = descendancy = _fmt = nselectors = optfatal = 0;
212 	prtheader = showthreads = wflag = xkeep_implied = 0;
213 	xkeep = -1;			/* Neither -x nor -X. */
214 	init_list(&gidlist, addelem_gid, sizeof(gid_t), "group");
215 	init_list(&jidlist, addelem_jid, sizeof(int), "jail id");
216 	init_list(&pgrplist, addelem_pid, sizeof(pid_t), "process group");
217 	init_list(&pidlist, addelem_pid, sizeof(pid_t), "process id");
218 	init_list(&ruidlist, addelem_uid, sizeof(uid_t), "ruser");
219 	init_list(&sesslist, addelem_pid, sizeof(pid_t), "session id");
220 	init_list(&ttylist, addelem_tty, sizeof(dev_t), "tty");
221 	init_list(&uidlist, addelem_uid, sizeof(uid_t), "user");
222 	memf = _PATH_DEVNULL;
223 	nlistf = NULL;
224 	while ((ch = getopt(argc, argv, PS_ARGS)) != -1)
225 		switch (ch) {
226 		case 'A':
227 			/*
228 			 * Exactly the same as `-ax'.   This has been
229 			 * added for compatibility with SUSv3, but for
230 			 * now it will not be described in the man page.
231 			 */
232 			nselectors++;
233 			all = xkeep = 1;
234 			break;
235 		case 'a':
236 			nselectors++;
237 			all = 1;
238 			break;
239 		case 'C':
240 			rawcpu = 1;
241 			break;
242 		case 'c':
243 			cflag = 1;
244 			break;
245 		case 'd':
246 			descendancy = 1;
247 			break;
248 		case 'e':			/* XXX set ufmt */
249 			needenv = 1;
250 			break;
251 #ifdef LAZY_PS
252 		case 'f':
253 			if (getuid() == 0 || getgid() == 0)
254 				forceuread = 1;
255 			break;
256 #endif
257 		case 'G':
258 			add_list(&gidlist, optarg);
259 			xkeep_implied = 1;
260 			nselectors++;
261 			break;
262 		case 'g':
263 #if 0
264 			/*-
265 			 * XXX - This SUSv3 behavior is still under debate
266 			 *	since it conflicts with the (undocumented)
267 			 *	`-g' option.  So we skip it for now.
268 			 */
269 			add_list(&pgrplist, optarg);
270 			xkeep_implied = 1;
271 			nselectors++;
272 			break;
273 #else
274 			/* The historical BSD-ish (from SunOS) behavior. */
275 			break;			/* no-op */
276 #endif
277 		case 'H':
278 			showthreads = KERN_PROC_INC_THREAD;
279 			break;
280 		case 'h':
281 			prtheader = ws.ws_row > 5 ? ws.ws_row : 22;
282 			break;
283 		case 'J':
284 			add_list(&jidlist, optarg);
285 			xkeep_implied = 1;
286 			nselectors++;
287 			break;
288 		case 'j':
289 			parsefmt(jfmt, 0);
290 			_fmt = 1;
291 			jfmt[0] = '\0';
292 			break;
293 		case 'L':
294 			showkey();
295 			exit(0);
296 		case 'l':
297 			parsefmt(lfmt, 0);
298 			_fmt = 1;
299 			lfmt[0] = '\0';
300 			break;
301 		case 'M':
302 			memf = optarg;
303 			break;
304 		case 'm':
305 			sortby = SORTMEM;
306 			break;
307 		case 'N':
308 			nlistf = optarg;
309 			break;
310 		case 'O':
311 			parsefmt(o1, 1);
312 			parsefmt(optarg, 1);
313 			parsefmt(o2, 1);
314 			o1[0] = o2[0] = '\0';
315 			_fmt = 1;
316 			break;
317 		case 'o':
318 			parsefmt(optarg, 1);
319 			_fmt = 1;
320 			break;
321 		case 'p':
322 			add_list(&pidlist, optarg);
323 			/*
324 			 * Note: `-p' does not *set* xkeep, but any values
325 			 * from pidlist are checked before xkeep is.  That
326 			 * way they are always matched, even if the user
327 			 * specifies `-X'.
328 			 */
329 			nselectors++;
330 			break;
331 #if 0
332 		case 'R':
333 			/*-
334 			 * XXX - This un-standard option is still under
335 			 *	debate.  This is what SUSv3 defines as
336 			 *	the `-U' option, and while it would be
337 			 *	nice to have, it could cause even more
338 			 *	confusion to implement it as `-R'.
339 			 */
340 			add_list(&ruidlist, optarg);
341 			xkeep_implied = 1;
342 			nselectors++;
343 			break;
344 #endif
345 		case 'r':
346 			sortby = SORTCPU;
347 			break;
348 		case 'S':
349 			sumrusage = 1;
350 			break;
351 #if 0
352 		case 's':
353 			/*-
354 			 * XXX - This non-standard option is still under
355 			 *	debate.  This *is* supported on Solaris,
356 			 *	Linux, and IRIX, but conflicts with `-s'
357 			 *	on NetBSD and maybe some older BSD's.
358 			 */
359 			add_list(&sesslist, optarg);
360 			xkeep_implied = 1;
361 			nselectors++;
362 			break;
363 #endif
364 		case 'T':
365 			if ((optarg = ttyname(STDIN_FILENO)) == NULL)
366 				errx(1, "stdin: not a terminal");
367 			/* FALLTHROUGH */
368 		case 't':
369 			add_list(&ttylist, optarg);
370 			xkeep_implied = 1;
371 			nselectors++;
372 			break;
373 		case 'U':
374 			/* This is what SUSv3 defines as the `-u' option. */
375 			add_list(&uidlist, optarg);
376 			xkeep_implied = 1;
377 			nselectors++;
378 			break;
379 		case 'u':
380 			parsefmt(ufmt, 0);
381 			sortby = SORTCPU;
382 			_fmt = 1;
383 			ufmt[0] = '\0';
384 			break;
385 		case 'v':
386 			parsefmt(vfmt, 0);
387 			sortby = SORTMEM;
388 			_fmt = 1;
389 			vfmt[0] = '\0';
390 			break;
391 		case 'w':
392 			if (wflag)
393 				termwidth = UNLIMITED;
394 			else if (termwidth < 131)
395 				termwidth = 131;
396 			wflag++;
397 			break;
398 		case 'X':
399 			/*
400 			 * Note that `-X' and `-x' are not standard "selector"
401 			 * options. For most selector-options, we check *all*
402 			 * processes to see if any are matched by the given
403 			 * value(s).  After we have a set of all the matched
404 			 * processes, then `-X' and `-x' govern whether we
405 			 * modify that *matched* set for processes which do
406 			 * not have a controlling terminal.  `-X' causes
407 			 * those processes to be deleted from the matched
408 			 * set, while `-x' causes them to be kept.
409 			 */
410 			xkeep = 0;
411 			break;
412 		case 'x':
413 			xkeep = 1;
414 			break;
415 		case 'Z':
416 			parsefmt(Zfmt, 0);
417 			Zfmt[0] = '\0';
418 			break;
419 		case '?':
420 		default:
421 			usage();
422 		}
423 	argc -= optind;
424 	argv += optind;
425 
426 	/*
427 	 * If there arguments after processing all the options, attempt
428 	 * to treat them as a list of process ids.
429 	 */
430 	while (*argv) {
431 		if (!isdigitch(**argv))
432 			break;
433 		add_list(&pidlist, *argv);
434 		argv++;
435 	}
436 	if (*argv) {
437 		fprintf(stderr, "%s: illegal argument: %s\n",
438 		    getprogname(), *argv);
439 		usage();
440 	}
441 	if (optfatal)
442 		exit(1);		/* Error messages already printed. */
443 	if (xkeep < 0)			/* Neither -X nor -x was specified. */
444 		xkeep = xkeep_implied;
445 
446 	kd = kvm_openfiles(nlistf, memf, NULL, O_RDONLY, errbuf);
447 	if (kd == 0)
448 		errx(1, "%s", errbuf);
449 
450 	if (!_fmt)
451 		parsefmt(dfmt, 0);
452 
453 	if (nselectors == 0) {
454 		uidlist.l.ptr = malloc(sizeof(uid_t));
455 		if (uidlist.l.ptr == NULL)
456 			errx(1, "malloc failed");
457 		nselectors = 1;
458 		uidlist.count = uidlist.maxcount = 1;
459 		*uidlist.l.uids = getuid();
460 	}
461 
462 	/*
463 	 * scan requested variables, noting what structures are needed,
464 	 * and adjusting header widths as appropriate.
465 	 */
466 	scanvars();
467 
468 	/*
469 	 * Get process list.  If the user requested just one selector-
470 	 * option, then kvm_getprocs can be asked to return just those
471 	 * processes.  Otherwise, have it return all processes, and
472 	 * then this routine will search that full list and select the
473 	 * processes which match any of the user's selector-options.
474 	 */
475 	what = showthreads != 0 ? KERN_PROC_ALL : KERN_PROC_PROC;
476 	flag = 0;
477 	if (nselectors == 1) {
478 		if (gidlist.count == 1) {
479 			what = KERN_PROC_RGID | showthreads;
480 			flag = *gidlist.l.gids;
481 			nselectors = 0;
482 		} else if (pgrplist.count == 1) {
483 			what = KERN_PROC_PGRP | showthreads;
484 			flag = *pgrplist.l.pids;
485 			nselectors = 0;
486 		} else if (pidlist.count == 1) {
487 			what = KERN_PROC_PID | showthreads;
488 			flag = *pidlist.l.pids;
489 			nselectors = 0;
490 		} else if (ruidlist.count == 1) {
491 			what = KERN_PROC_RUID | showthreads;
492 			flag = *ruidlist.l.uids;
493 			nselectors = 0;
494 		} else if (sesslist.count == 1) {
495 			what = KERN_PROC_SESSION | showthreads;
496 			flag = *sesslist.l.pids;
497 			nselectors = 0;
498 		} else if (ttylist.count == 1) {
499 			what = KERN_PROC_TTY | showthreads;
500 			flag = *ttylist.l.ttys;
501 			nselectors = 0;
502 		} else if (uidlist.count == 1) {
503 			what = KERN_PROC_UID | showthreads;
504 			flag = *uidlist.l.uids;
505 			nselectors = 0;
506 		} else if (all) {
507 			/* No need for this routine to select processes. */
508 			nselectors = 0;
509 		}
510 	}
511 
512 	/*
513 	 * select procs
514 	 */
515 	nentries = -1;
516 	kp = kvm_getprocs(kd, what, flag, &nentries);
517 	if ((kp == NULL && nentries > 0) || (kp != NULL && nentries < 0))
518 		errx(1, "%s", kvm_geterr(kd));
519 	nkept = 0;
520 	if (nentries > 0) {
521 		if ((kinfo = malloc(nentries * sizeof(*kinfo))) == NULL)
522 			errx(1, "malloc failed");
523 		for (i = nentries; --i >= 0; ++kp) {
524 			/*
525 			 * If the user specified multiple selection-criteria,
526 			 * then keep any process matched by the inclusive OR
527 			 * of all the selection-criteria given.
528 			 */
529 			if (pidlist.count > 0) {
530 				for (elem = 0; elem < pidlist.count; elem++)
531 					if (kp->ki_pid == pidlist.l.pids[elem])
532 						goto keepit;
533 			}
534 			/*
535 			 * Note that we had to process pidlist before
536 			 * filtering out processes which do not have
537 			 * a controlling terminal.
538 			 */
539 			if (xkeep == 0) {
540 				if ((kp->ki_tdev == NODEV ||
541 				    (kp->ki_flag & P_CONTROLT) == 0))
542 					continue;
543 			}
544 			if (nselectors == 0)
545 				goto keepit;
546 			if (gidlist.count > 0) {
547 				for (elem = 0; elem < gidlist.count; elem++)
548 					if (kp->ki_rgid == gidlist.l.gids[elem])
549 						goto keepit;
550 			}
551 			if (jidlist.count > 0) {
552 				for (elem = 0; elem < jidlist.count; elem++)
553 					if (kp->ki_jid == jidlist.l.jids[elem])
554 						goto keepit;
555 			}
556 			if (pgrplist.count > 0) {
557 				for (elem = 0; elem < pgrplist.count; elem++)
558 					if (kp->ki_pgid ==
559 					    pgrplist.l.pids[elem])
560 						goto keepit;
561 			}
562 			if (ruidlist.count > 0) {
563 				for (elem = 0; elem < ruidlist.count; elem++)
564 					if (kp->ki_ruid ==
565 					    ruidlist.l.uids[elem])
566 						goto keepit;
567 			}
568 			if (sesslist.count > 0) {
569 				for (elem = 0; elem < sesslist.count; elem++)
570 					if (kp->ki_sid == sesslist.l.pids[elem])
571 						goto keepit;
572 			}
573 			if (ttylist.count > 0) {
574 				for (elem = 0; elem < ttylist.count; elem++)
575 					if (kp->ki_tdev == ttylist.l.ttys[elem])
576 						goto keepit;
577 			}
578 			if (uidlist.count > 0) {
579 				for (elem = 0; elem < uidlist.count; elem++)
580 					if (kp->ki_uid == uidlist.l.uids[elem])
581 						goto keepit;
582 			}
583 			/*
584 			 * This process did not match any of the user's
585 			 * selector-options, so skip the process.
586 			 */
587 			continue;
588 
589 		keepit:
590 			next_KINFO = &kinfo[nkept];
591 			next_KINFO->ki_p = kp;
592 			next_KINFO->ki_d.level = 0;
593 			next_KINFO->ki_d.prefix = NULL;
594 			next_KINFO->ki_pcpu = getpcpu(next_KINFO);
595 			if (sortby == SORTMEM)
596 				next_KINFO->ki_memsize = kp->ki_tsize +
597 				    kp->ki_dsize + kp->ki_ssize;
598 			if (needuser)
599 				saveuser(next_KINFO);
600 			nkept++;
601 		}
602 	}
603 
604 	sizevars();
605 
606 	if (nkept == 0) {
607 		printheader();
608 		exit(1);
609 	}
610 
611 	/*
612 	 * sort proc list
613 	 */
614 	qsort(kinfo, nkept, sizeof(KINFO), pscomp);
615 
616 	/*
617 	 * We want things in descendant order
618 	 */
619 	if (descendancy)
620 		descendant_sort(kinfo, nkept);
621 
622 
623 	/*
624 	 * Prepare formatted output.
625 	 */
626 	for (i = 0; i < nkept; i++)
627 		format_output(&kinfo[i]);
628 
629 	/*
630 	 * Print header.
631 	 */
632 	printheader();
633 
634 	/*
635 	 * Output formatted lines.
636 	 */
637 	for (i = lineno = 0; i < nkept; i++) {
638 		linelen = 0;
639 		STAILQ_FOREACH(vent, &varlist, next_ve) {
640 	        	if (vent->var->flag & LJUST)
641 				fmtstr = "%-*s";
642 			else
643 				fmtstr = "%*s";
644 
645 			ks = STAILQ_FIRST(&kinfo[i].ki_ks);
646 			STAILQ_REMOVE_HEAD(&kinfo[i].ki_ks, ks_next);
647 			/* Truncate rightmost column if necessary.  */
648 			if (STAILQ_NEXT(vent, next_ve) == NULL &&
649 			   termwidth != UNLIMITED && ks->ks_str != NULL) {
650 				left = termwidth - linelen;
651 				if (left > 0 && left < (int)strlen(ks->ks_str))
652 					ks->ks_str[left] = '\0';
653 			}
654 			str = ks->ks_str;
655 			if (str == NULL)
656 				str = "-";
657 			/* No padding for the last column, if it's LJUST. */
658 			if (STAILQ_NEXT(vent, next_ve) == NULL &&
659 			    vent->var->flag & LJUST)
660 				linelen += printf(fmtstr, 0, str);
661 			else
662 				linelen += printf(fmtstr, vent->var->width, str);
663 
664 			if (ks->ks_str != NULL) {
665 				free(ks->ks_str);
666 				ks->ks_str = NULL;
667 			}
668 			free(ks);
669 			ks = NULL;
670 
671 			if (STAILQ_NEXT(vent, next_ve) != NULL) {
672 				(void)putchar(' ');
673 				linelen++;
674 			}
675 		}
676 		(void)putchar('\n');
677 		if (prtheader && lineno++ == prtheader - 4) {
678 			(void)putchar('\n');
679 			printheader();
680 			lineno = 0;
681 		}
682 	}
683 	free_list(&gidlist);
684 	free_list(&jidlist);
685 	free_list(&pidlist);
686 	free_list(&pgrplist);
687 	free_list(&ruidlist);
688 	free_list(&sesslist);
689 	free_list(&ttylist);
690 	free_list(&uidlist);
691 	for (i = 0; i < nkept; i++)
692 		free(kinfo[i].ki_d.prefix);
693 	free(kinfo);
694 
695 	exit(eval);
696 }
697 
698 static int
699 addelem_gid(struct listinfo *inf, const char *elem)
700 {
701 	struct group *grp;
702 	const char *nameorID;
703 	char *endp;
704 	u_long bigtemp;
705 
706 	if (*elem == '\0' || strlen(elem) >= MAXLOGNAME) {
707 		if (*elem == '\0')
708 			warnx("Invalid (zero-length) %s name", inf->lname);
709 		else
710 			warnx("%s name too long: %s", inf->lname, elem);
711 		optfatal = 1;
712 		return (0);		/* Do not add this value. */
713 	}
714 
715 	/*
716 	 * SUSv3 states that `ps -G grouplist' should match "real-group
717 	 * ID numbers", and does not mention group-names.  I do want to
718 	 * also support group-names, so this tries for a group-id first,
719 	 * and only tries for a name if that doesn't work.  This is the
720 	 * opposite order of what is done in addelem_uid(), but in
721 	 * practice the order would only matter for group-names which
722 	 * are all-numeric.
723 	 */
724 	grp = NULL;
725 	nameorID = "named";
726 	errno = 0;
727 	bigtemp = strtoul(elem, &endp, 10);
728 	if (errno == 0 && *endp == '\0' && bigtemp <= GID_MAX) {
729 		nameorID = "name or ID matches";
730 		grp = getgrgid((gid_t)bigtemp);
731 	}
732 	if (grp == NULL)
733 		grp = getgrnam(elem);
734 	if (grp == NULL) {
735 		warnx("No %s %s '%s'", inf->lname, nameorID, elem);
736 		optfatal = 1;
737 		return (0);
738 	}
739 	if (inf->count >= inf->maxcount)
740 		expand_list(inf);
741 	inf->l.gids[(inf->count)++] = grp->gr_gid;
742 	return (1);
743 }
744 
745 static int
746 addelem_jid(struct listinfo *inf, const char *elem)
747 {
748 	int tempid;
749 
750 	if (*elem == '\0') {
751 		warnx("Invalid (zero-length) jail id");
752 		optfatal = 1;
753 		return (0);		/* Do not add this value. */
754 	}
755 
756 	tempid = jail_getid(elem);
757 	if (tempid < 0) {
758 		warnx("Invalid %s: %s", inf->lname, elem);
759 		optfatal = 1;
760 		return (0);
761 	}
762 
763 	if (inf->count >= inf->maxcount)
764 		expand_list(inf);
765 	inf->l.jids[(inf->count)++] = tempid;
766 	return (1);
767 }
768 
769 static int
770 addelem_pid(struct listinfo *inf, const char *elem)
771 {
772 	char *endp;
773 	long tempid;
774 
775 	if (*elem == '\0') {
776 		warnx("Invalid (zero-length) process id");
777 		optfatal = 1;
778 		return (0);		/* Do not add this value. */
779 	}
780 
781 	errno = 0;
782 	tempid = strtol(elem, &endp, 10);
783 	if (*endp != '\0' || tempid < 0 || elem == endp) {
784 		warnx("Invalid %s: %s", inf->lname, elem);
785 		errno = ERANGE;
786 	} else if (errno != 0 || tempid > pid_max) {
787 		warnx("%s too large: %s", inf->lname, elem);
788 		errno = ERANGE;
789 	}
790 	if (errno == ERANGE) {
791 		optfatal = 1;
792 		return (0);
793 	}
794 	if (inf->count >= inf->maxcount)
795 		expand_list(inf);
796 	inf->l.pids[(inf->count)++] = tempid;
797 	return (1);
798 }
799 
800 /*-
801  * The user can specify a device via one of three formats:
802  *     1) fully qualified, e.g.:     /dev/ttyp0 /dev/console	/dev/pts/0
803  *     2) missing "/dev", e.g.:      ttyp0      console		pts/0
804  *     3) two-letters, e.g.:         p0         co		0
805  *        (matching letters that would be seen in the "TT" column)
806  */
807 static int
808 addelem_tty(struct listinfo *inf, const char *elem)
809 {
810 	const char *ttypath;
811 	struct stat sb;
812 	char pathbuf[PATH_MAX], pathbuf2[PATH_MAX], pathbuf3[PATH_MAX];
813 
814 	ttypath = NULL;
815 	pathbuf2[0] = '\0';
816 	pathbuf3[0] = '\0';
817 	switch (*elem) {
818 	case '/':
819 		ttypath = elem;
820 		break;
821 	case 'c':
822 		if (strcmp(elem, "co") == 0) {
823 			ttypath = _PATH_CONSOLE;
824 			break;
825 		}
826 		/* FALLTHROUGH */
827 	default:
828 		strlcpy(pathbuf, _PATH_DEV, sizeof(pathbuf));
829 		strlcat(pathbuf, elem, sizeof(pathbuf));
830 		ttypath = pathbuf;
831 		if (strncmp(pathbuf, _PATH_TTY, strlen(_PATH_TTY)) == 0)
832 			break;
833 		if (strncmp(pathbuf, _PATH_PTS, strlen(_PATH_PTS)) == 0)
834 			break;
835 		if (strcmp(pathbuf, _PATH_CONSOLE) == 0)
836 			break;
837 		/* Check to see if /dev/tty${elem} exists */
838 		strlcpy(pathbuf2, _PATH_TTY, sizeof(pathbuf2));
839 		strlcat(pathbuf2, elem, sizeof(pathbuf2));
840 		if (stat(pathbuf2, &sb) == 0 && S_ISCHR(sb.st_mode)) {
841 			/* No need to repeat stat() && S_ISCHR() checks */
842 			ttypath = NULL;
843 			break;
844 		}
845 		/* Check to see if /dev/pts/${elem} exists */
846 		strlcpy(pathbuf3, _PATH_PTS, sizeof(pathbuf3));
847 		strlcat(pathbuf3, elem, sizeof(pathbuf3));
848 		if (stat(pathbuf3, &sb) == 0 && S_ISCHR(sb.st_mode)) {
849 			/* No need to repeat stat() && S_ISCHR() checks */
850 			ttypath = NULL;
851 			break;
852 		}
853 		break;
854 	}
855 	if (ttypath) {
856 		if (stat(ttypath, &sb) == -1) {
857 			if (pathbuf3[0] != '\0')
858 				warn("%s, %s, and %s", pathbuf3, pathbuf2,
859 				    ttypath);
860 			else
861 				warn("%s", ttypath);
862 			optfatal = 1;
863 			return (0);
864 		}
865 		if (!S_ISCHR(sb.st_mode)) {
866 			if (pathbuf3[0] != '\0')
867 				warnx("%s, %s, and %s: Not a terminal",
868 				    pathbuf3, pathbuf2, ttypath);
869 			else
870 				warnx("%s: Not a terminal", ttypath);
871 			optfatal = 1;
872 			return (0);
873 		}
874 	}
875 	if (inf->count >= inf->maxcount)
876 		expand_list(inf);
877 	inf->l.ttys[(inf->count)++] = sb.st_rdev;
878 	return (1);
879 }
880 
881 static int
882 addelem_uid(struct listinfo *inf, const char *elem)
883 {
884 	struct passwd *pwd;
885 	char *endp;
886 	u_long bigtemp;
887 
888 	if (*elem == '\0' || strlen(elem) >= MAXLOGNAME) {
889 		if (*elem == '\0')
890 			warnx("Invalid (zero-length) %s name", inf->lname);
891 		else
892 			warnx("%s name too long: %s", inf->lname, elem);
893 		optfatal = 1;
894 		return (0);		/* Do not add this value. */
895 	}
896 
897 	pwd = getpwnam(elem);
898 	if (pwd == NULL) {
899 		errno = 0;
900 		bigtemp = strtoul(elem, &endp, 10);
901 		if (errno != 0 || *endp != '\0' || bigtemp > UID_MAX)
902 			warnx("No %s named '%s'", inf->lname, elem);
903 		else {
904 			/* The string is all digits, so it might be a userID. */
905 			pwd = getpwuid((uid_t)bigtemp);
906 			if (pwd == NULL)
907 				warnx("No %s name or ID matches '%s'",
908 				    inf->lname, elem);
909 		}
910 	}
911 	if (pwd == NULL) {
912 		/*
913 		 * These used to be treated as minor warnings (and the
914 		 * option was simply ignored), but now they are fatal
915 		 * errors (and the command will be aborted).
916 		 */
917 		optfatal = 1;
918 		return (0);
919 	}
920 	if (inf->count >= inf->maxcount)
921 		expand_list(inf);
922 	inf->l.uids[(inf->count)++] = pwd->pw_uid;
923 	return (1);
924 }
925 
926 static void
927 add_list(struct listinfo *inf, const char *argp)
928 {
929 	const char *savep;
930 	char *cp, *endp;
931 	int toolong;
932 	char elemcopy[PATH_MAX];
933 
934 	if (*argp == '\0')
935 		inf->addelem(inf, argp);
936 	while (*argp != '\0') {
937 		while (*argp != '\0' && strchr(W_SEP, *argp) != NULL)
938 			argp++;
939 		savep = argp;
940 		toolong = 0;
941 		cp = elemcopy;
942 		if (strchr(T_SEP, *argp) == NULL) {
943 			endp = elemcopy + sizeof(elemcopy) - 1;
944 			while (*argp != '\0' && cp <= endp &&
945 			    strchr(W_SEP T_SEP, *argp) == NULL)
946 				*cp++ = *argp++;
947 			if (cp > endp)
948 				toolong = 1;
949 		}
950 		if (!toolong) {
951 			*cp = '\0';
952 			/*
953 			 * Add this single element to the given list.
954 			 */
955 			inf->addelem(inf, elemcopy);
956 		} else {
957 			/*
958 			 * The string is too long to copy.  Find the end
959 			 * of the string to print out the warning message.
960 			 */
961 			while (*argp != '\0' && strchr(W_SEP T_SEP,
962 			    *argp) == NULL)
963 				argp++;
964 			warnx("Value too long: %.*s", (int)(argp - savep),
965 			    savep);
966 			optfatal = 1;
967 		}
968 		/*
969 		 * Skip over any number of trailing whitespace characters,
970 		 * but only one (at most) trailing element-terminating
971 		 * character.
972 		 */
973 		while (*argp != '\0' && strchr(W_SEP, *argp) != NULL)
974 			argp++;
975 		if (*argp != '\0' && strchr(T_SEP, *argp) != NULL) {
976 			argp++;
977 			/* Catch case where string ended with a comma. */
978 			if (*argp == '\0')
979 				inf->addelem(inf, argp);
980 		}
981 	}
982 }
983 
984 static void
985 descendant_sort(KINFO *ki, int items)
986 {
987 	int dst, lvl, maxlvl, n, ndst, nsrc, siblings, src;
988 	unsigned char *path;
989 	KINFO kn;
990 
991 	/*
992 	 * First, sort the entries by descendancy, tracking the descendancy
993 	 * depth in the ki_d.level field.
994 	 */
995 	src = 0;
996 	maxlvl = 0;
997 	while (src < items) {
998 		if (ki[src].ki_d.level) {
999 			src++;
1000 			continue;
1001 		}
1002 		for (nsrc = 1; src + nsrc < items; nsrc++)
1003 			if (!ki[src + nsrc].ki_d.level)
1004 				break;
1005 
1006 		for (dst = 0; dst < items; dst++) {
1007 			if (ki[dst].ki_p->ki_pid == ki[src].ki_p->ki_pid)
1008 				continue;
1009 			if (ki[dst].ki_p->ki_pid == ki[src].ki_p->ki_ppid)
1010 				break;
1011 		}
1012 
1013 		if (dst == items) {
1014 			src += nsrc;
1015 			continue;
1016 		}
1017 
1018 		for (ndst = 1; dst + ndst < items; ndst++)
1019 			if (ki[dst + ndst].ki_d.level <= ki[dst].ki_d.level)
1020 				break;
1021 
1022 		for (n = src; n < src + nsrc; n++) {
1023 			ki[n].ki_d.level += ki[dst].ki_d.level + 1;
1024 			if (maxlvl < ki[n].ki_d.level)
1025 				maxlvl = ki[n].ki_d.level;
1026 		}
1027 
1028 		while (nsrc) {
1029 			if (src < dst) {
1030 				kn = ki[src];
1031 				memmove(ki + src, ki + src + 1,
1032 				    (dst - src + ndst - 1) * sizeof *ki);
1033 				ki[dst + ndst - 1] = kn;
1034 				nsrc--;
1035 				dst--;
1036 				ndst++;
1037 			} else if (src != dst + ndst) {
1038 				kn = ki[src];
1039 				memmove(ki + dst + ndst + 1, ki + dst + ndst,
1040 				    (src - dst - ndst) * sizeof *ki);
1041 				ki[dst + ndst] = kn;
1042 				ndst++;
1043 				nsrc--;
1044 				src++;
1045 			} else {
1046 				ndst += nsrc;
1047 				src += nsrc;
1048 				nsrc = 0;
1049 			}
1050 		}
1051 	}
1052 
1053 	/*
1054 	 * Now populate ki_d.prefix (instead of ki_d.level) with the command
1055 	 * prefix used to show descendancies.
1056 	 */
1057 	path = malloc((maxlvl + 7) / 8);
1058 	memset(path, '\0', (maxlvl + 7) / 8);
1059 	for (src = 0; src < items; src++) {
1060 		if ((lvl = ki[src].ki_d.level) == 0) {
1061 			ki[src].ki_d.prefix = NULL;
1062 			continue;
1063 		}
1064 		if ((ki[src].ki_d.prefix = malloc(lvl * 2 + 1)) == NULL)
1065 			errx(1, "malloc failed");
1066 		for (n = 0; n < lvl - 2; n++) {
1067 			ki[src].ki_d.prefix[n * 2] =
1068 			    path[n / 8] & 1 << (n % 8) ? '|' : ' ';
1069 			ki[src].ki_d.prefix[n * 2 + 1] = ' ';
1070 		}
1071 		if (n == lvl - 2) {
1072 			/* Have I any more siblings? */
1073 			for (siblings = 0, dst = src + 1; dst < items; dst++) {
1074 				if (ki[dst].ki_d.level > lvl)
1075 					continue;
1076 				if (ki[dst].ki_d.level == lvl)
1077 					siblings = 1;
1078 				break;
1079 			}
1080 			if (siblings)
1081 				path[n / 8] |= 1 << (n % 8);
1082 			else
1083 				path[n / 8] &= ~(1 << (n % 8));
1084 			ki[src].ki_d.prefix[n * 2] = siblings ? '|' : '`';
1085 			ki[src].ki_d.prefix[n * 2 + 1] = '-';
1086 			n++;
1087 		}
1088 		strcpy(ki[src].ki_d.prefix + n * 2, "- ");
1089 	}
1090 	free(path);
1091 }
1092 
1093 static void *
1094 expand_list(struct listinfo *inf)
1095 {
1096 	void *newlist;
1097 	int newmax;
1098 
1099 	newmax = (inf->maxcount + 1) << 1;
1100 	newlist = realloc(inf->l.ptr, newmax * inf->elemsize);
1101 	if (newlist == NULL) {
1102 		free(inf->l.ptr);
1103 		errx(1, "realloc to %d %ss failed", newmax, inf->lname);
1104 	}
1105 	inf->maxcount = newmax;
1106 	inf->l.ptr = newlist;
1107 
1108 	return (newlist);
1109 }
1110 
1111 static void
1112 free_list(struct listinfo *inf)
1113 {
1114 
1115 	inf->count = inf->elemsize = inf->maxcount = 0;
1116 	if (inf->l.ptr != NULL)
1117 		free(inf->l.ptr);
1118 	inf->addelem = NULL;
1119 	inf->lname = NULL;
1120 	inf->l.ptr = NULL;
1121 }
1122 
1123 static void
1124 init_list(struct listinfo *inf, addelem_rtn artn, int elemsize,
1125     const char *lname)
1126 {
1127 
1128 	inf->count = inf->maxcount = 0;
1129 	inf->elemsize = elemsize;
1130 	inf->addelem = artn;
1131 	inf->lname = lname;
1132 	inf->l.ptr = NULL;
1133 }
1134 
1135 VARENT *
1136 find_varentry(VAR *v)
1137 {
1138 	struct varent *vent;
1139 
1140 	STAILQ_FOREACH(vent, &varlist, next_ve) {
1141 		if (strcmp(vent->var->name, v->name) == 0)
1142 			return vent;
1143 	}
1144 	return NULL;
1145 }
1146 
1147 static void
1148 scanvars(void)
1149 {
1150 	struct varent *vent;
1151 	VAR *v;
1152 
1153 	STAILQ_FOREACH(vent, &varlist, next_ve) {
1154 		v = vent->var;
1155 		if (v->flag & USER)
1156 			needuser = 1;
1157 		if (v->flag & COMM)
1158 			needcomm = 1;
1159 	}
1160 }
1161 
1162 static void
1163 format_output(KINFO *ki)
1164 {
1165 	struct varent *vent;
1166 	VAR *v;
1167 	KINFO_STR *ks;
1168 	char *str;
1169 	int len;
1170 
1171 	STAILQ_INIT(&ki->ki_ks);
1172 	STAILQ_FOREACH(vent, &varlist, next_ve) {
1173 		v = vent->var;
1174 		str = (v->oproc)(ki, vent);
1175 		ks = malloc(sizeof(*ks));
1176 		if (ks == NULL)
1177 			errx(1, "malloc failed");
1178 		ks->ks_str = str;
1179 		STAILQ_INSERT_TAIL(&ki->ki_ks, ks, ks_next);
1180 		if (str != NULL) {
1181 			len = strlen(str);
1182 		} else
1183 			len = 1; /* "-" */
1184 		if (v->width < len)
1185 			v->width = len;
1186 	}
1187 }
1188 
1189 static void
1190 sizevars(void)
1191 {
1192 	struct varent *vent;
1193 	VAR *v;
1194 	int i;
1195 
1196 	STAILQ_FOREACH(vent, &varlist, next_ve) {
1197 		v = vent->var;
1198 		i = strlen(vent->header);
1199 		if (v->width < i)
1200 			v->width = i;
1201 	}
1202 }
1203 
1204 static const char *
1205 fmt(char **(*fn)(kvm_t *, const struct kinfo_proc *, int), KINFO *ki,
1206     char *comm, char *thread, int maxlen)
1207 {
1208 	const char *s;
1209 
1210 	s = fmt_argv((*fn)(kd, ki->ki_p, termwidth), comm,
1211 	    showthreads && ki->ki_p->ki_numthreads > 1 ? thread : NULL, maxlen);
1212 	return (s);
1213 }
1214 
1215 #define UREADOK(ki)	(forceuread || (ki->ki_p->ki_flag & P_INMEM))
1216 
1217 static void
1218 saveuser(KINFO *ki)
1219 {
1220 
1221 	if (ki->ki_p->ki_flag & P_INMEM) {
1222 		/*
1223 		 * The u-area might be swapped out, and we can't get
1224 		 * at it because we have a crashdump and no swap.
1225 		 * If it's here fill in these fields, otherwise, just
1226 		 * leave them 0.
1227 		 */
1228 		ki->ki_valid = 1;
1229 	} else
1230 		ki->ki_valid = 0;
1231 	/*
1232 	 * save arguments if needed
1233 	 */
1234 	if (needcomm) {
1235 		if (ki->ki_p->ki_stat == SZOMB)
1236 			ki->ki_args = strdup("<defunct>");
1237 		else if (UREADOK(ki) || (ki->ki_p->ki_args != NULL))
1238 			ki->ki_args = strdup(fmt(kvm_getargv, ki,
1239 			    ki->ki_p->ki_comm, ki->ki_p->ki_tdname, MAXCOMLEN));
1240 		else
1241 			asprintf(&ki->ki_args, "(%s)", ki->ki_p->ki_comm);
1242 		if (ki->ki_args == NULL)
1243 			errx(1, "malloc failed");
1244 	} else {
1245 		ki->ki_args = NULL;
1246 	}
1247 	if (needenv) {
1248 		if (UREADOK(ki))
1249 			ki->ki_env = strdup(fmt(kvm_getenvv, ki,
1250 			    (char *)NULL, (char *)NULL, 0));
1251 		else
1252 			ki->ki_env = strdup("()");
1253 		if (ki->ki_env == NULL)
1254 			errx(1, "malloc failed");
1255 	} else {
1256 		ki->ki_env = NULL;
1257 	}
1258 }
1259 
1260 /* A macro used to improve the readability of pscomp(). */
1261 #define	DIFF_RETURN(a, b, field) do {	\
1262 	if ((a)->field != (b)->field)	\
1263 		return (((a)->field < (b)->field) ? -1 : 1); 	\
1264 } while (0)
1265 
1266 static int
1267 pscomp(const void *a, const void *b)
1268 {
1269 	const KINFO *ka, *kb;
1270 
1271 	ka = a;
1272 	kb = b;
1273 	/* SORTCPU and SORTMEM are sorted in descending order. */
1274 	if (sortby == SORTCPU)
1275 		DIFF_RETURN(kb, ka, ki_pcpu);
1276 	if (sortby == SORTMEM)
1277 		DIFF_RETURN(kb, ka, ki_memsize);
1278 	/*
1279 	 * TTY's are sorted in ascending order, except that all NODEV
1280 	 * processes come before all processes with a device.
1281 	 */
1282 	if (ka->ki_p->ki_tdev != kb->ki_p->ki_tdev) {
1283 		if (ka->ki_p->ki_tdev == NODEV)
1284 			return (-1);
1285 		if (kb->ki_p->ki_tdev == NODEV)
1286 			return (1);
1287 		DIFF_RETURN(ka, kb, ki_p->ki_tdev);
1288 	}
1289 
1290 	/* PID's and TID's (threads) are sorted in ascending order. */
1291 	DIFF_RETURN(ka, kb, ki_p->ki_pid);
1292 	DIFF_RETURN(ka, kb, ki_p->ki_tid);
1293 	return (0);
1294 }
1295 #undef DIFF_RETURN
1296 
1297 /*
1298  * ICK (all for getopt), would rather hide the ugliness
1299  * here than taint the main code.
1300  *
1301  *  ps foo -> ps -foo
1302  *  ps 34 -> ps -p34
1303  *
1304  * The old convention that 't' with no trailing tty arg means the users
1305  * tty, is only supported if argv[1] doesn't begin with a '-'.  This same
1306  * feature is available with the option 'T', which takes no argument.
1307  */
1308 static char *
1309 kludge_oldps_options(const char *optlist, char *origval, const char *nextarg)
1310 {
1311 	size_t len;
1312 	char *argp, *cp, *newopts, *ns, *optp, *pidp;
1313 
1314 	/*
1315 	 * See if the original value includes any option which takes an
1316 	 * argument (and will thus use up the remainder of the string).
1317 	 */
1318 	argp = NULL;
1319 	if (optlist != NULL) {
1320 		for (cp = origval; *cp != '\0'; cp++) {
1321 			optp = strchr(optlist, *cp);
1322 			if ((optp != NULL) && *(optp + 1) == ':') {
1323 				argp = cp;
1324 				break;
1325 			}
1326 		}
1327 	}
1328 	if (argp != NULL && *origval == '-')
1329 		return (origval);
1330 
1331 	/*
1332 	 * if last letter is a 't' flag with no argument (in the context
1333 	 * of the oldps options -- option string NOT starting with a '-' --
1334 	 * then convert to 'T' (meaning *this* terminal, i.e. ttyname(0)).
1335 	 *
1336 	 * However, if a flag accepting a string argument is found earlier
1337 	 * in the option string (including a possible `t' flag), then the
1338 	 * remainder of the string must be the argument to that flag; so
1339 	 * do not modify that argument.  Note that a trailing `t' would
1340 	 * cause argp to be set, if argp was not already set by some
1341 	 * earlier option.
1342 	 */
1343 	len = strlen(origval);
1344 	cp = origval + len - 1;
1345 	pidp = NULL;
1346 	if (*cp == 't' && *origval != '-' && cp == argp) {
1347 		if (nextarg == NULL || *nextarg == '-' || isdigitch(*nextarg))
1348 			*cp = 'T';
1349 	} else if (argp == NULL) {
1350 		/*
1351 		 * The original value did not include any option which takes
1352 		 * an argument (and that would include `p' and `t'), so check
1353 		 * the value for trailing number, or comma-separated list of
1354 		 * numbers, which we will treat as a pid request.
1355 		 */
1356 		if (isdigitch(*cp)) {
1357 			while (cp >= origval && (*cp == ',' || isdigitch(*cp)))
1358 				--cp;
1359 			pidp = cp + 1;
1360 		}
1361 	}
1362 
1363 	/*
1364 	 * If nothing needs to be added to the string, then return
1365 	 * the "original" (although possibly modified) value.
1366 	 */
1367 	if (*origval == '-' && pidp == NULL)
1368 		return (origval);
1369 
1370 	/*
1371 	 * Create a copy of the string to add '-' and/or 'p' to the
1372 	 * original value.
1373 	 */
1374 	if ((newopts = ns = malloc(len + 3)) == NULL)
1375 		errx(1, "malloc failed");
1376 
1377 	if (*origval != '-')
1378 		*ns++ = '-';	/* add option flag */
1379 
1380 	if (pidp == NULL)
1381 		strcpy(ns, origval);
1382 	else {
1383 		/*
1384 		 * Copy everything before the pid string, add the `p',
1385 		 * and then copy the pid string.
1386 		 */
1387 		len = pidp - origval;
1388 		memcpy(ns, origval, len);
1389 		ns += len;
1390 		*ns++ = 'p';
1391 		strcpy(ns, pidp);
1392 	}
1393 
1394 	return (newopts);
1395 }
1396 
1397 static void
1398 pidmax_init(void)
1399 {
1400 	size_t intsize;
1401 
1402 	intsize = sizeof(pid_max);
1403 	if (sysctlbyname("kern.pid_max", &pid_max, &intsize, NULL, 0) < 0) {
1404 		warn("unable to read kern.pid_max");
1405 		pid_max = 99999;
1406 	}
1407 }
1408 
1409 static void
1410 usage(void)
1411 {
1412 #define	SINGLE_OPTS	"[-aCcde" OPT_LAZY_f "HhjlmrSTuvwXxZ]"
1413 
1414 	(void)fprintf(stderr, "%s\n%s\n%s\n%s\n",
1415 	    "usage: ps " SINGLE_OPTS " [-O fmt | -o fmt] [-G gid[,gid...]]",
1416 	    "          [-J jid[,jid...]] [-M core] [-N system]",
1417 	    "          [-p pid[,pid...]] [-t tty[,tty...]] [-U user[,user...]]",
1418 	    "       ps [-L]");
1419 	exit(1);
1420 }
1421