xref: /dragonfly/bin/ps/ps.c (revision a4da4a90)
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  * 3. 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) 1990, 1993, 1994 The Regents of the University of California.  All rights reserved.
30  * @(#)ps.c	8.4 (Berkeley) 4/2/94
31  * $FreeBSD: src/bin/ps/ps.c,v 1.30.2.6 2002/07/04 08:30:37 sobomax Exp $
32  */
33 
34 #include <sys/user.h>
35 #include <sys/param.h>
36 #include <sys/time.h>
37 #include <sys/queue.h>
38 #include <sys/resource.h>
39 #include <sys/stat.h>
40 #include <sys/ioctl.h>
41 #include <sys/sysctl.h>
42 #include <sys/mount.h>
43 
44 #include <ctype.h>
45 #include <err.h>
46 #include <errno.h>
47 #include <fcntl.h>
48 #include <kvm.h>
49 #include <limits.h>
50 #include <locale.h>
51 #include <nlist.h>
52 #include <paths.h>
53 #include <stdio.h>
54 #include <stdlib.h>
55 #include <string.h>
56 #include <unistd.h>
57 #include <pwd.h>
58 
59 #include "ps.h"
60 
61 #define SEP ", \t"		/* username separators */
62 
63 #define KHSIZE	2048
64 #define KHMASK	(KHSIZE - 1)
65 
66 KINFO *KInfo;
67 KINFO **KSort;
68 struct varent *vhead, *vtail;
69 
70 int	eval;			/* exit value */
71 int	cflag;			/* -c */
72 int	rawcpu;			/* -C */
73 int	sumrusage;		/* -S */
74 int	termwidth;		/* width of screen (0 == infinity) */
75 int	totwidth;		/* calculated width of requested variables */
76 int	numcpus;		/* hw.ncpu */
77 int	showtid;		/* -H */
78 
79 static int needuser, needcomm, needenv;
80 #if defined(LAZY_PS)
81 static int forceuread=0;
82 #define PS_ARGS	"AaCcefgHhjLlM:mN:O:o:p:rRSTt:U:uvwx"
83 #else
84 static int forceuread=1;
85 #define PS_ARGS	"AaCcegHhjLlM:mN:O:o:p:rRSTt:U:uvwx"
86 #endif
87 
88 enum sort { DEFAULT, SORTMEM, SORTCPU } sortby = DEFAULT;
89 
90 static const char *getfmt (char **(*)(kvm_t *, const struct kinfo_proc *, int),
91 		    KINFO *, char *, int);
92 static char	*kludge_oldps_options (char *);
93 static int	 pscomp (const void *, const void *);
94 static void	 dochain (KINFO **ksort, int *nentriesp, pid_t pid);
95 static void	 saveuser (KINFO *);
96 static void	 scanvars (void);
97 static void	 dynsizevars (KINFO *);
98 static void	 sizevars (void);
99 static int	 check_procfs(void);
100 static void	 usage (void);
101 static uid_t	*getuids(const char *, int *);
102 
103 struct timeval btime;
104 
105 static char dfmt[] = "pid tt state time command";
106 static char jfmt[] = "user pid ppid pgid sess jobc state tt time command";
107 static char lfmt[] = "uid pid ppid cpu pri nice vsz rss wchan state tt time command";
108 static char   o1[] = "pid";
109 static char   o2[] = "tt state time command";
110 static char ufmt[] = "user pid %cpu %mem vsz rss tt state start time command";
111 static char vfmt[] = "pid state time sl re pagein vsz rss lim tsiz %cpu %mem command";
112 
113 kvm_t *kd;
114 
115 int
116 main(int argc, char **argv)
117 {
118 	struct kinfo_proc *kp;
119 	struct varent *vent;
120 	struct winsize ws;
121 	dev_t ttydev;
122 	pid_t pid;
123 	uid_t *uids;
124 	int all, ch, flag, i, fmt, ofmt, lineno, nentries, nocludge, dropgid;
125 	int prtheader, wflag, what, xflg, uid, nuids;
126 	int chainflg;
127 	char errbuf[_POSIX2_LINE_MAX];
128 	const char *cp, *nlistf, *memf;
129 	size_t btime_size = sizeof(struct timeval);
130 	size_t numcpus_size = sizeof(numcpus);
131 
132 	setlocale(LC_ALL, "");
133 
134 	if ((ioctl(STDOUT_FILENO, TIOCGWINSZ, (char *)&ws) == -1 &&
135 	     ioctl(STDERR_FILENO, TIOCGWINSZ, (char *)&ws) == -1 &&
136 	     ioctl(STDIN_FILENO,  TIOCGWINSZ, (char *)&ws) == -1) ||
137 	     ws.ws_col == 0)
138 		termwidth = 79;
139 	else
140 		termwidth = ws.ws_col - 1;
141 
142 	/*
143 	 * Don't apply a kludge if the first argument is an option taking an
144 	 * argument
145 	 */
146 	if (argc > 1) {
147 		nocludge = 0;
148 		if (argv[1][0] == '-') {
149 			for (cp = PS_ARGS; *cp != '\0'; cp++) {
150 				if (*cp != ':')
151 					continue;
152 				if (*(cp - 1) == argv[1][1]) {
153 					nocludge = 1;
154 					break;
155 				}
156 			}
157 		}
158 		if (nocludge == 0)
159 			argv[1] = kludge_oldps_options(argv[1]);
160 	}
161 
162 	all = fmt = ofmt = prtheader = wflag = xflg = showtid = 0;
163 	chainflg = 0;
164 	pid = -1;
165 	nuids = 0;
166 	uids = NULL;
167 	ttydev = NODEV;
168 	dropgid = 0;
169 	memf = nlistf = _PATH_DEVNULL;
170 
171 	while ((ch = getopt(argc, argv, PS_ARGS)) != -1) {
172 		switch((char)ch) {
173 		case 'A':
174 			all = xflg = 1;
175 			break;
176 		case 'a':
177 			all = 1;
178 			break;
179 		case 'C':
180 			rawcpu = 1;
181 			break;
182 		case 'c':
183 			cflag = 1;
184 			break;
185 		case 'e':			/* XXX set ufmt */
186 			needenv = 1;
187 			break;
188 		case 'g':
189 			break;			/* no-op */
190 		case 'H':
191 			showtid = KERN_PROC_FLAG_LWP;
192 			break;
193 		case 'h':
194 			prtheader = ws.ws_row > 5 ? ws.ws_row : 22;
195 			break;
196 		case 'j':
197 			parsefmt(jfmt);
198 			fmt = 1;
199 			jfmt[0] = '\0';
200 			break;
201 		case 'L':
202 			showkey();
203 			exit(0);
204 		case 'l':
205 			parsefmt(lfmt);
206 			fmt = 1;
207 			lfmt[0] = '\0';
208 			break;
209 		case 'M':
210 			memf = optarg;
211 			dropgid = 1;
212 			break;
213 		case 'm':
214 			sortby = SORTMEM;
215 			break;
216 		case 'N':
217 			nlistf = optarg;
218 			dropgid = 1;
219 			break;
220 		case 'O':
221 			parsefmt(o1);
222 			parsefmt(optarg);
223 			parsefmt(o2);
224 			o1[0] = o2[0] = '\0';
225 			fmt = 1;
226 			break;
227 		case 'o':
228 			parsefmt(optarg);
229 			fmt = ofmt = 1;
230 			break;
231 #if defined(LAZY_PS)
232 		case 'f':
233 			if (getuid() == 0 || getgid() == 0)
234 			    forceuread = 1;
235 			break;
236 #endif
237 		case 'p':
238 			pid = atol(optarg);
239 			xflg = 1;
240 			break;
241 		case 'r':
242 			sortby = SORTCPU;
243 			break;
244 		case 'R':
245 			chainflg = 1;
246 			break;
247 		case 'S':
248 			sumrusage = 1;
249 			break;
250 		case 'T':
251 			if ((optarg = ttyname(STDIN_FILENO)) == NULL)
252 				errx(1, "stdin: not a terminal");
253 			/* FALLTHROUGH */
254 		case 't': {
255 			struct stat sb;
256 			char pathbuf[PATH_MAX];
257 			const char *ttypath;
258 
259 			if (strcmp(optarg, "co") == 0) {
260 				ttypath = _PATH_CONSOLE;
261 			} else if (*optarg >= '0' && *optarg <= '9') {
262 				snprintf(pathbuf, sizeof(pathbuf),
263 					 "%spts/%s", _PATH_DEV, optarg);
264 				ttypath = pathbuf;
265 			} else if (*optarg != '/') {
266 				snprintf(pathbuf, sizeof(pathbuf),
267 					 "%s%s", _PATH_TTY, optarg);
268 				ttypath = pathbuf;
269 			} else {
270 				ttypath = optarg;
271 			}
272 			if (stat(ttypath, &sb) == -1)
273 				err(1, "%s", ttypath);
274 			if (!S_ISCHR(sb.st_mode))
275 				errx(1, "%s: not a terminal", ttypath);
276 			ttydev = sb.st_rdev;
277 			break;
278 		}
279 		case 'U':
280 			uids = getuids(optarg, &nuids);
281 			xflg++;		/* XXX: intuitive? */
282 			break;
283 		case 'u':
284 			parsefmt(ufmt);
285 			sortby = SORTCPU;
286 			fmt = 1;
287 			ufmt[0] = '\0';
288 			break;
289 		case 'v':
290 			parsefmt(vfmt);
291 			sortby = SORTMEM;
292 			fmt = 1;
293 			vfmt[0] = '\0';
294 			break;
295 		case 'w':
296 			if (wflag)
297 				termwidth = UNLIMITED;
298 			else if (termwidth < 131)
299 				termwidth = 131;
300 			wflag++;
301 			break;
302 		case 'x':
303 			xflg = 1;
304 			break;
305 		case '?':
306 		default:
307 			usage();
308 		}
309 	}
310 	argc -= optind;
311 	argv += optind;
312 
313 	/*
314 	 * If the user specified ps -e then they want a copy of the process
315 	 * environment kvm_getenvv(3) attempts to open /proc/<pid>/mem.
316 	 * Check to make sure that procfs is mounted on /proc, otherwise
317 	 * print a warning informing the user that output will be incomplete.
318 	 */
319 	if (needenv == 1 && check_procfs() == 0)
320 		warnx("Process environment requires procfs(5)");
321 
322 #define	BACKWARD_COMPATIBILITY
323 #ifdef	BACKWARD_COMPATIBILITY
324 	if (*argv) {
325 		nlistf = *argv;
326 		if (*++argv) {
327 			memf = *argv;
328 		}
329 	}
330 #endif
331 	/*
332 	 * Discard setgid privileges if not the running kernel so that bad
333 	 * guys can't print interesting stuff from kernel memory.
334 	 */
335 	if (dropgid) {
336 		setgid(getgid());
337 		setuid(getuid());
338 	}
339 
340 	kd = kvm_openfiles(nlistf, memf, NULL, O_RDONLY, errbuf);
341 	if (kd == NULL)
342 		errx(1, "%s", errbuf);
343 
344 	if (!fmt)
345 		parsefmt(dfmt);
346 
347 	/*
348 	 * Add TID to output format if requested unless user-specific format
349 	 * selected.
350 	 */
351 	if (showtid && !ofmt)
352 		insert_tid_in_fmt();
353 
354 	/* XXX - should be cleaner */
355 	if (!all && ttydev == NODEV && pid == -1 && !nuids) {
356 		if ((uids = malloc(sizeof (*uids))) == NULL)
357 			errx(1, "malloc: %s", strerror(errno));
358 		nuids = 1;
359 		*uids = getuid();
360 	}
361 
362 	/*
363 	 * scan requested variables, noting what structures are needed,
364 	 * and adjusting header widths as appropriate.
365 	 */
366 	scanvars();
367 
368 	/*
369 	 * Get boot time
370 	 */
371 	if (sysctlbyname("kern.boottime", &btime, &btime_size, NULL, 0) < 0) {
372 		perror("sysctl: kern.boottime");
373 		exit(EXIT_FAILURE);
374 	}
375 
376 	/*
377 	 * Get number of cpus
378 	 */
379 	if (sysctlbyname("hw.ncpu", &numcpus, &numcpus_size, NULL, 0) < 0)
380 		numcpus = 1;
381 
382 	/*
383 	 * get proc list
384 	 */
385 	if (nuids == 1) {
386 		what = KERN_PROC_UID;
387 		flag = *uids;
388 	} else if (ttydev != NODEV) {
389 		what = KERN_PROC_TTY;
390 		flag = ttydev;
391 	} else if (pid != -1 && chainflg == 0) {
392 		what = KERN_PROC_PID;
393 		flag = pid;
394 	} else {
395 		what = KERN_PROC_ALL;
396 		flag = 0;
397 	}
398 	what |= showtid;
399 
400 	/*
401 	 * select procs
402 	 */
403 	if ((kp = kvm_getprocs(kd, what, flag, &nentries)) == NULL)
404 		errx(1, "%s", kvm_geterr(kd));
405 	if ((KInfo = calloc(nentries, sizeof(KINFO))) == NULL)
406 		err(1, NULL);
407 	if ((KSort = malloc(nentries * sizeof(KINFO *))) == NULL)
408 		err(1, NULL);
409 
410 	for (i = 0; i < nentries; ++i) {
411 		KInfo[i].ki_proc = &kp[i];
412 		KInfo[i].ki_indent = -1;
413 		KInfo[i].ki_ctailp = &KInfo[i].ki_cbase;
414 		if (needuser)
415 			saveuser(&KInfo[i]);
416 		dynsizevars(&KInfo[i]);
417 		KSort[i] = &KInfo[i];
418 	}
419 
420 	sizevars();
421 
422 	/*
423 	 * print header
424 	 */
425 	printheader();
426 	if (nentries == 0)
427 		exit(1);
428 	/*
429 	 * sort proc list
430 	 */
431 	qsort(KSort, nentries, sizeof(KINFO *), pscomp);
432 
433 	/*
434 	 * rejigger and indent children, parent(s) and children
435 	 * at each level retain the above sort characteristics.
436 	 */
437 	if (chainflg)
438 		dochain(KSort, &nentries, pid);
439 
440 	/*
441 	 * for each proc, call each variable output function.
442 	 */
443 	for (i = lineno = 0; i < nentries; i++) {
444 		if (xflg == 0 && (KI_PROC(KSort[i], tdev) == NODEV ||
445 		    (KI_PROC(KSort[i], flags) & P_CONTROLT ) == 0))
446 			continue;
447 		if (nuids > 1) {
448 			for (uid = 0; uid < nuids; uid++)
449 				if (KI_PROC(KSort[i], uid) ==
450 				    uids[uid])
451 					break;
452 			if (uid == nuids)
453 				continue;
454 		}
455 		STAILQ_FOREACH(vent, &var_head, link) {
456 			(vent->var->oproc)(KSort[i], vent);
457 			if (STAILQ_NEXT(vent, link) != NULL)
458 				putchar(' ');
459 		}
460 		putchar('\n');
461 		if (prtheader && lineno++ == prtheader - 4) {
462 			putchar('\n');
463 			printheader();
464 			lineno = 0;
465 		}
466 	}
467 	free(uids);
468 
469 	exit(eval);
470 }
471 
472 uid_t *
473 getuids(const char *arg, int *nuids)
474 {
475 	char name[MAXLOGNAME];
476 	struct passwd *pwd;
477 	uid_t *uids, *moreuids;
478 	size_t l;
479 	int alloc;
480 
481 
482 	alloc = 0;
483 	*nuids = 0;
484 	uids = NULL;
485 	for (; (l = strcspn(arg, SEP)) > 0; arg += l + strspn(arg + l, SEP)) {
486 		if (l >= sizeof name) {
487 			warnx("%.*s: name too long", (int)l, arg);
488 			continue;
489 		}
490 		strncpy(name, arg, l);
491 		name[l] = '\0';
492 		if ((pwd = getpwnam(name)) == NULL) {
493 			warnx("%s: no such user", name);
494 			continue;
495 		}
496 		if (*nuids >= alloc) {
497 			alloc = (alloc + 1) << 1;
498 			moreuids = realloc(uids, alloc * sizeof (*uids));
499 			if (moreuids == NULL) {
500 				free(uids);
501 				errx(1, "realloc: %s", strerror(errno));
502 			}
503 			uids = moreuids;
504 		}
505 		uids[(*nuids)++] = pwd->pw_uid;
506 	}
507 	endpwent();
508 
509 	if (!*nuids)
510 		errx(1, "No users specified");
511 
512 	return uids;
513 }
514 
515 static void
516 scanvars(void)
517 {
518 	struct varent *vent;
519 	const VAR *v;
520 
521 	STAILQ_FOREACH(vent, &var_head, link) {
522 		v = vent->var;
523 		if (v->flag & DSIZ) {
524 			vent->dwidth = vent->width;
525 			vent->width = 0;
526 		}
527 		if (v->flag & USER)
528 			needuser = 1;
529 		if (v->flag & COMM)
530 			needcomm = 1;
531 	}
532 }
533 
534 static void
535 dynsizevars(KINFO *ki)
536 {
537 	struct varent *vent;
538 	const VAR *v;
539 	int i;
540 
541 	STAILQ_FOREACH(vent, &var_head, link) {
542 		v = vent->var;
543 		if (!(v->flag & DSIZ))
544 			continue;
545 		i = (v->sproc)( ki);
546 		if (vent->width < i)
547 			vent->width = i;
548 		if (vent->width > vent->dwidth)
549 			vent->width = vent->dwidth;
550 	}
551 }
552 
553 static void
554 sizevars(void)
555 {
556 	struct varent *vent;
557 	int i;
558 
559 	STAILQ_FOREACH(vent, &var_head, link) {
560 		i = strlen(vent->header);
561 		if (vent->width < i)
562 			vent->width = i;
563 		totwidth += vent->width + 1;	/* +1 for space */
564 	}
565 	totwidth--;
566 }
567 
568 static const char *
569 getfmt(char **(*fn) (kvm_t *, const struct kinfo_proc *, int), KINFO *ki, char
570     *comm, int maxlen)
571 {
572 	const char *s;
573 
574 	if ((s =
575 	    fmt_argv((*fn)(kd, ki->ki_proc, termwidth), comm, maxlen)) == NULL)
576 		err(1, NULL);
577 	return (s);
578 }
579 
580 static void
581 saveuser(KINFO *ki)
582 {
583 	/*
584 	 * save arguments if needed
585 	 */
586 	if (needcomm) {
587 		ki->ki_args = getfmt(kvm_getargv, ki, KI_PROC(ki, comm),
588 		    MAXCOMLEN);
589 	} else {
590 		ki->ki_args = NULL;
591 	}
592 	if (needenv) {
593 		ki->ki_env = getfmt(kvm_getenvv, ki, NULL, 0);
594 	} else {
595 		ki->ki_env = NULL;
596 	}
597 }
598 
599 static int
600 pscomp(const void *arg_a, const void *arg_b)
601 {
602 	const KINFO *a = *(KINFO * const *)arg_a;
603 	const KINFO *b = *(KINFO * const *)arg_b;
604 	double di;
605 	segsz_t si;
606 	int i;
607 
608 #define VSIZE(k) (KI_PROC(k, vm_dsize) + KI_PROC(k, vm_ssize) + \
609 		  KI_PROC(k, vm_tsize))
610 
611 #if 0
612 	if (sortby == SORTIAC)
613 		return (KI_PROC(a)->p_usdata.bsd4.interactive - KI_PROC(b)->p_usdata.bsd4.interactive);
614 #endif
615 	if (sortby == SORTCPU) {
616 		di = getpcpu(b) - getpcpu(a);
617 		if (di < 0.0)
618 			return(-1);
619 		if (di > 0.0)
620 			return(+1);
621 		/* fall through */
622 	}
623 	if (sortby == SORTMEM) {
624 		si = VSIZE(b) - VSIZE(a);
625 		if (si < 0)
626 			return(-1);
627 		if (si > 0)
628 			return(+1);
629 		/* fall through */
630 	}
631 	i = KI_PROC(a, tdev) - KI_PROC(b, tdev);
632 	if (i == 0)
633 		i = KI_PROC(a, pid) - KI_PROC(b, pid);
634 	return (i);
635 }
636 
637 /*
638  * Chain (-R) option.  Sub-sorts by parent/child association.
639  */
640 static int dochain_final(KINFO **kfinal, KINFO *base, int j);
641 
642 static void
643 dochain (KINFO **ksort, int *nentriesp, pid_t pid)
644 {
645 	int nentries = *nentriesp;
646 	int i;
647 	int j;
648 	int hi;
649 	pid_t ppid;
650 	KINFO *scan;
651 	KINFO **khash;
652 	KINFO **kfinal;
653 
654 	/*
655 	 * First hash all the pids so we can quickly locate the
656 	 * parent pids.
657 	 */
658 	khash = calloc(KHSIZE, sizeof(KINFO *));
659 	kfinal = calloc(nentries, sizeof(KINFO *));
660 
661 	for (i = 0; i < nentries; ++i) {
662 		hi = KI_PROC(ksort[i], pid) & KHMASK;
663 
664 		ksort[i]->ki_hnext = khash[hi];
665 		khash[hi] = ksort[i];
666 	}
667 
668 	/*
669 	 * Now run through the list and create the parent associations.
670 	 */
671 	for (i = 0; i < nentries; ++i) {
672 		ppid = KI_PROC(ksort[i], ppid);
673 
674 		if (ppid <= 0 || KI_PROC(ksort[i], pid) <= 0) {
675 			scan = NULL;
676 		} else {
677 			for (scan = khash[ppid & KHMASK];
678 			     scan;
679 			     scan = scan->ki_hnext) {
680 				if (ppid == KI_PROC(scan, pid))
681 					break;
682 			}
683 		}
684 		if (scan) {
685 			ksort[i]->ki_parent = scan;
686 			*scan->ki_ctailp = ksort[i];
687 			scan->ki_ctailp = &ksort[i]->ki_cnext;
688 		}
689 	}
690 
691 	/*
692 	 * Now regenerate the list starting at root entries, then copyback.
693 	 */
694 	for (i = j = 0; i < nentries; ++i) {
695 		if (pid != (pid_t)-1) {
696 			if (KI_PROC(ksort[i], pid) == pid) {
697 				ksort[i]->ki_indent = 0;
698 				j = dochain_final(kfinal, ksort[i], j);
699 			}
700 		} else if (ksort[i]->ki_parent == NULL) {
701 			ksort[i]->ki_indent = 0;
702 			j = dochain_final(kfinal, ksort[i], j);
703 		}
704 	}
705 
706 	/*
707 	 * There might be fewer entries if we restricted the chain to a
708 	 * pid.
709 	 */
710 	nentries = j;
711 	*nentriesp = nentries;
712 
713 	if (nentries)
714 		bcopy(kfinal, ksort, nentries * sizeof(kfinal[0]));
715 	free(kfinal);
716 	free(khash);
717 }
718 
719 static int
720 dochain_final(KINFO **kfinal, KINFO *base, int j)
721 {
722 	KINFO *scan;
723 
724 	kfinal[j++] = base;
725 	for (scan = base->ki_cbase; scan; scan = scan->ki_cnext) {
726 		/*
727 		 * Don't let us loop
728 		 */
729 		if (scan->ki_indent >= 0)
730 			continue;
731 		scan->ki_indent = base->ki_indent + 1;
732 		j = dochain_final(kfinal, scan, j);
733 	}
734 	return (j);
735 }
736 
737 /*
738  * ICK (all for getopt), would rather hide the ugliness
739  * here than taint the main code.
740  *
741  *  ps foo -> ps -foo
742  *  ps 34 -> ps -p34
743  *
744  * The old convention that 't' with no trailing tty arg means the users
745  * tty, is only supported if argv[1] doesn't begin with a '-'.  This same
746  * feature is available with the option 'T', which takes no argument.
747  */
748 static char *
749 kludge_oldps_options(char *s)
750 {
751 	size_t len;
752 	char *newopts, *ns, *cp;
753 
754 	len = strlen(s);
755 	if ((newopts = ns = malloc(len + 2)) == NULL)
756 		err(1, NULL);
757 	/*
758 	 * options begin with '-'
759 	 */
760 	if (*s != '-')
761 		*ns++ = '-';	/* add option flag */
762 
763 	/*
764 	 * gaze to end of argv[1]
765 	 */
766 	cp = s + len - 1;
767 
768 	/*
769 	 * if last letter is a 't' flag with no argument (in the context
770 	 * of the oldps options -- option string NOT starting with a '-' --
771 	 * then convert to 'T' (meaning *this* terminal, i.e. ttyname(0)).
772 	 *
773 	 * However, if a flag accepting a string argument is found in the
774 	 * option string, the remainder of the string is the argument to
775 	 * that flag; do not modify that argument.
776 	 */
777 	if (strcspn(s, "MNOoU") == len && *cp == 't' && *s != '-') {
778 		*cp = 'T';
779 	} else {
780 		/*
781 		 * otherwise check for trailing number, which *may* be a
782 		 * pid.
783 		 */
784 		while (cp >= s && isdigit(*cp))
785 			--cp;
786 	}
787 	cp++;
788 	memmove(ns, s, (size_t)(cp - s));	/* copy up to trailing number */
789 	ns += cp - s;
790 	/*
791 	 * if there's a trailing number, and not a preceding 'p' (pid) or
792 	 * 't' (tty) flag, then assume it's a pid and insert a 'p' flag.
793 	 */
794 	if (isdigit(*cp) &&
795 	    (cp == s || (cp[-1] != 't' && cp[-1] != 'p')) &&
796 	    (cp - 1 == s || cp[-2] != 't')) {
797 		*ns++ = 'p';
798 	}
799 	strcpy(ns, cp);		/* and append the number */
800 
801 	return (newopts);
802 }
803 
804 static int
805 check_procfs(void)
806 {
807 	struct statfs mnt;
808 
809 	if (statfs("/proc", &mnt) < 0)
810 		return (0);
811 	if (strcmp(mnt.f_fstypename, "procfs") != 0)
812 		return (0);
813 	return (1);
814 }
815 
816 static void
817 usage(void)
818 {
819 
820 	fprintf(stderr, "%s\n%s\n%s\n",
821 	    "usage: ps [-aCcefhHjlmrSTuvwx] [-M core] [-N system] [-O fmt] [-o fmt] [-p pid]",
822 	    "          [-t tty] [-U username]",
823 	    "       ps [-L]");
824 	exit(1);
825 }
826