xref: /freebsd/usr.bin/top/top.c (revision 2e3f49888ec8851bafb22011533217487764fdb0)
1 /*-
2  *  Top users/processes display for Unix
3  *
4  *  This program may be freely redistributed,
5  *  but this entire comment MUST remain intact.
6  *
7  *  Copyright (c) 1984, 1989, William LeFebvre, Rice University
8  *  Copyright (c) 1989 - 1994, William LeFebvre, Northwestern University
9  *  Copyright (c) 1994, 1995, William LeFebvre, Argonne National Laboratory
10  *  Copyright (c) 1996, William LeFebvre, Group sys Consulting
11  */
12 
13 #include <sys/types.h>
14 #include <sys/time.h>
15 #include <sys/cdefs.h>
16 #include <sys/limits.h>
17 #include <sys/resource.h>
18 #include <sys/select.h>
19 #include <sys/signal.h>
20 
21 #include <assert.h>
22 #include <err.h>
23 #include <errno.h>
24 #include <getopt.h>
25 #include <jail.h>
26 #include <locale.h>
27 #include <stdbool.h>
28 #include <stdio.h>
29 #include <stdlib.h>
30 #include <signal.h>
31 #include <string.h>
32 #include <unistd.h>
33 
34 #include "commands.h"
35 #include "display.h"		/* interface to display package */
36 #include "screen.h"		/* interface to screen package */
37 #include "top.h"
38 #include "machine.h"
39 #include "utils.h"
40 #include "username.h"
41 
42 /* Size of the stdio buffer given to stdout */
43 #define Buffersize	2048
44 
45 char copyright[] =
46     "Copyright (c) 1984 through 1996, William LeFebvre";
47 
48 typedef void sigret_t;
49 
50 /* The buffer that stdio will use */
51 static char stdoutbuf[Buffersize];
52 
53 static int fmt_flags = 0;
54 int show_args = false;
55 int pcpu_stats = false;
56 
57 /* signal handling routines */
58 static sigret_t leave(int);
59 static sigret_t tstop(int);
60 static sigret_t top_winch(int);
61 
62 static volatile sig_atomic_t leaveflag;
63 static volatile sig_atomic_t tstopflag;
64 static volatile sig_atomic_t winchflag;
65 
66 /* values which need to be accessed by signal handlers */
67 static int max_topn;		/* maximum displayable processes */
68 
69 /* miscellaneous things */
70 struct process_select ps;
71 pid_t mypid;
72 
73 /* pointers to display routines */
74 static void (*d_loadave)(int mpid, double *avenrun) = i_loadave;
75 static void (*d_procstates)(int total, int *brkdn) = i_procstates;
76 static void (*d_cpustates)(int *states) = i_cpustates;
77 static void (*d_memory)(int *stats) = i_memory;
78 static void (*d_arc)(int *stats) = i_arc;
79 static void (*d_carc)(int *stats) = i_carc;
80 static void (*d_swap)(int *stats) = i_swap;
81 static void (*d_message)(void) = i_message;
82 static void (*d_header)(const char *text) = i_header;
83 static void (*d_process)(int line, char *thisline) = i_process;
84 
85 static void reset_display(void);
86 
87 static const struct option longopts[] = {
88     { "cpu-display-mode", no_argument, NULL, 'C' }, /* differs from orignal */
89     /* D reserved */
90     { "thread", no_argument, NULL, 'H' },
91     { "idle-procs", no_argument, NULL, 'I' },
92 	{ "jail", required_argument, NULL, 'J' },
93 	{ "per-cpu", no_argument, NULL, 'P' },
94     { "system-procs", no_argument, NULL, 'S' },
95     { "thread-id", no_argument, NULL, 'T' }, /* differs from orignal */
96     { "user", required_argument, NULL, 'U' },
97     { "all", no_argument, NULL, 'a' },
98     { "batch", no_argument, NULL, 'b' },
99     /* c reserved */
100     { "displays", required_argument, NULL, 'd' },
101     { "interactive", no_argument, NULL, 'i' },
102     { "jail-id", no_argument, NULL, 'j' },
103     { "display-mode", required_argument, NULL, 'm' },
104     /* n is identical to batch */
105     { "sort-order", required_argument, NULL, 'o' },
106     { "pid", required_argument, NULL, 'p' },
107     { "quick", no_argument, NULL, 'q' },
108     { "delay", required_argument, NULL, 's' },
109     { "threads", no_argument, NULL, 't' },
110     { "uids", no_argument, NULL, 'u' },
111     { "version", no_argument, NULL, 'v' },
112 	{ "swap", no_argument, NULL, 'w' },
113 	{ "system-idle-procs", no_argument, NULL, 'z' },
114 	{ NULL, 0, NULL, 0 }
115 };
116 
117 static void
118 reset_uids(void)
119 {
120     for (size_t i = 0; i < TOP_MAX_UIDS; ++i)
121 	ps.uid[i] = -1;
122 }
123 
124 static int
125 add_uid(int uid)
126 {
127     size_t i = 0;
128 
129     /* Add the uid if there's room */
130     for (; i < TOP_MAX_UIDS; ++i)
131     {
132 	if (ps.uid[i] == -1 || ps.uid[i] == uid)
133 	{
134 	    ps.uid[i] = uid;
135 	    break;
136 	}
137     }
138 
139     return (i == TOP_MAX_UIDS);
140 }
141 
142 static void
143 rem_uid(int uid)
144 {
145     size_t i = 0;
146     size_t where = TOP_MAX_UIDS;
147 
148     /* Look for the user to remove - no problem if it's not there */
149     for (; i < TOP_MAX_UIDS; ++i)
150     {
151 	if (ps.uid[i] == -1)
152 	    break;
153 	if (ps.uid[i] == uid)
154 	    where = i;
155     }
156 
157     /* Make sure we don't leave a hole in the middle */
158     if (where != TOP_MAX_UIDS)
159     {
160 	ps.uid[where] = ps.uid[i-1];
161 	ps.uid[i-1] = -1;
162     }
163 }
164 
165 static int
166 handle_user(char *buf, size_t buflen)
167 {
168     int rc = 0;
169     int uid = -1;
170     char *buf2 = buf;
171 
172     new_message(MT_standout, "Username to show (+ for all): ");
173     if (readline(buf, buflen, false) <= 0)
174     {
175 	clear_message();
176 	return (rc);
177     }
178 
179     if (buf[0] == '+' || buf[0] == '-')
180     {
181 	if (buf[1] == '\0')
182 	{
183 	    reset_uids();
184 	    goto end;
185 	}
186 	else
187 	    ++buf2;
188     }
189 
190     if ((uid = userid(buf2)) == -1)
191     {
192 	new_message(MT_standout, " %s: unknown user", buf2);
193 	rc = 1;
194 	goto end;
195     }
196 
197     if (buf2 == buf)
198     {
199 	reset_uids();
200 	ps.uid[0] = uid;
201 	goto end;
202     }
203 
204     if (buf[0] == '+')
205     {
206 	if (add_uid(uid))
207 	{
208 	    new_message(MT_standout, " too many users, reset with '+'");
209 	    rc = 1;
210 	    goto end;
211 	}
212     }
213     else
214 	rem_uid(uid);
215 
216 end:
217     putchar('\r');
218     return (rc);
219 }
220 
221 int
222 main(int argc, const char *argv[])
223 {
224     int i;
225     int active_procs;
226 
227     struct system_info system_info;
228     struct statics statics;
229     void * processes;
230 
231     static char tempbuf1[50];
232     static char tempbuf2[50];
233 	sigset_t old_sigmask, new_sigmask;
234     int topn = Infinity;
235     struct timeval delay = { 2, 0 };
236     int displays = 0;		/* indicates unspecified */
237     int sel_ret = 0;
238     time_t curr_time;
239     char *(*get_userid)(int) = username;
240     const char *uname_field = "USERNAME";
241     const char *header_text;
242     char *env_top;
243     const char **preset_argv;
244     int  preset_argc = 0;
245     const char **av = NULL;
246     int  ac = -1;
247     bool do_unames = true;
248     char interactive = 2;
249     char warnings = 0;
250     char topn_specified = false;
251     char ch;
252     char no_command = 1;
253     struct timeval timeout;
254     char *order_name = NULL;
255     int order_index = 0;
256     fd_set readfds;
257 	char *nptr;
258 
259     /* set the buffer for stdout */
260 #ifdef DEBUG
261     extern FILE *debug;
262     debug = fopen("debug.run", "w");
263     setbuffer(stdout, NULL, 0);
264 #else
265     setbuffer(stdout, stdoutbuf, Buffersize);
266 #endif
267 
268     if (setlocale(LC_ALL, "") == NULL) {
269         fprintf(stderr, "invalid locale.\n");
270 	exit(1);
271     }
272 
273     mypid = getpid();
274 
275     /* get our name */
276     /* initialize some selection options */
277     ps.idle    = true;
278     ps.self    = true;
279     ps.system  = false;
280     reset_uids();
281     ps.thread  = false;
282     ps.wcpu    = 1;
283     ps.jid     = -1;
284     ps.jail    = false;
285     ps.swap    = false;
286     ps.kidle   = true;
287     ps.pid     = -1;
288     ps.command = NULL;
289     ps.thread_id = false;
290 
291     /* get preset options from the environment */
292     if ((env_top = getenv("TOP")) != NULL)
293     {
294 	av = preset_argv = argparse(env_top, &preset_argc);
295 	ac = preset_argc;
296 
297 	/* set the dummy argument to an explanatory message, in case
298 	   getopt encounters a bad argument */
299 	preset_argv[0] = "while processing environment";
300     }
301 
302     /* process options */
303     do {
304 	/* if we're done doing the presets, then process the real arguments */
305 	if (preset_argc == 0)
306 	{
307 	    ac = argc;
308 	    av = argv;
309 
310 	    /* this should keep getopt happy... */
311 	    optind = 1;
312 	}
313 
314 	while ((i = getopt_long(ac, __DECONST(char * const *, av), "CSIHPabijJ:nquvzs:d:U:m:o:p:Ttw", longopts, NULL)) != EOF)
315 	{
316 	    switch(i)
317 	    {
318 	      case 'v':			/* show version number */
319 			  errx(0, "version FreeBSD");
320 			  break;
321 
322 	      case 'u':			/* toggle uid/username display */
323 		do_unames = !do_unames;
324 		break;
325 
326 	      case 'U':			/* display only username's processes */
327 		if ((ps.uid[0] = userid(optarg)) == -1)
328 		{
329 		    errx(1, "%s: unknown user\n", optarg);
330 		}
331 		break;
332 
333 	      case 'S':			/* show system processes */
334 		ps.system = true;
335 		break;
336 
337 	      case 'I':                   /* show idle processes */
338 		ps.idle = !ps.idle;
339 		break;
340 
341 	      case 'i':			/* go interactive regardless */
342 		interactive = 1;
343 		break;
344 
345 	      case 'n':			/* batch, or non-interactive */
346 	      case 'b':
347 		interactive = 0;
348 		break;
349 
350 	      case 'a':
351 		fmt_flags ^= FMT_SHOWARGS;
352 		break;
353 
354 	      case 'd':			/* number of displays to show */
355 		if ((i = atoiwi(optarg)) == Invalid || i == 0)
356 		{
357 		    warnx("warning: display count should be positive -- option ignored");
358 		    warnings++;
359 		}
360 		else
361 		{
362 		    displays = i;
363 		}
364 		break;
365 	      case 'p': {
366 		unsigned long long num;
367 		const char *errstr;
368 
369 		num = strtonum(optarg, 0, INT_MAX, &errstr);
370 		if (errstr != NULL || !find_pid(num)) {
371 			fprintf(stderr, "%s: unknown pid\n", optarg);
372 			exit(1);
373 		}
374 		ps.pid = (pid_t)num;
375 		ps.system = true;
376 		break;
377 	      }
378 
379 	      case 's':
380 	      {
381 		  double delay_d = strtod(optarg, &nptr);
382 		  if (nptr == optarg)
383 		  {
384 		      warnx("warning: invalid delay");
385 		      warnings++;
386 		  }
387 		  else if (delay_d <= 0)
388 		  {
389 		      warnx("warning: seconds delay should be positive -- using default");
390 		      warnings++;
391 		  }
392 		  else
393 		  {
394 		      delay.tv_sec = delay_d;
395 		      delay.tv_usec = (delay_d - delay.tv_sec) * 1e6;
396 		  }
397 		  break;
398 	      }
399 
400 	      case 'q':		/* be quick about it */
401 			errno = 0;
402 			i = setpriority(PRIO_PROCESS, 0, PRIO_MIN);
403 			if (i == -1 && errno != 0) {
404 				warnx("warning: `-q' option failed (%m)");
405 				warnings++;
406 			}
407 		break;
408 
409 	      case 'm':		/* select display mode */
410 		if (strcmp(optarg, "io") == 0) {
411 			displaymode = DISP_IO;
412 		} else if (strcmp(optarg, "cpu") == 0) {
413 			displaymode = DISP_CPU;
414 		} else {
415 			errx(1, "warning: `-m' option can only take args 'io' or 'cpu'");
416 		}
417 		break;
418 
419 	      case 'o':		/* select sort order */
420 		order_name = optarg;
421 		break;
422 
423 	      case 't':
424 		ps.self = !ps.self;
425 		break;
426 
427 	      case 'C':
428 		ps.wcpu = !ps.wcpu;
429 		break;
430 
431 	      case 'H':
432 		ps.thread = !ps.thread;
433 		break;
434 
435 	      case 'T':
436 		ps.thread_id = !ps.thread_id;
437 		break;
438 
439 	      case 'j':
440 		ps.jail = !ps.jail;
441 		break;
442 
443 	      case 'J':			/* display only jail's processes */
444 		if ((ps.jid = jail_getid(optarg)) == -1)
445 		{
446 		    fprintf(stderr, "%s: unknown jail\n", optarg);
447 		    exit(1);
448 		}
449 		ps.jail = 1;
450 		break;
451 
452 	      case 'P':
453 		pcpu_stats = !pcpu_stats;
454 		break;
455 
456 	      case 'w':
457 		ps.swap = 1;
458 		break;
459 
460 	      case 'z':
461 		ps.kidle = !ps.kidle;
462 		break;
463 
464 	      default:
465 		errx(1,
466 "[-abCHIijnPqStuvwz] [-d count] [-J jail] [-m cpu | io] [-o field]\n"
467 "     [-p pid] [-s time] [-U username] [number]");
468 	    }
469 	}
470 
471 	/* get count of top processes to display (if any) */
472 	if (optind < ac)
473 	{
474 	    if ((topn = atoiwi(av[optind])) == Invalid)
475 	    {
476 			warnx("warning: process display count should be non-negative -- using default");
477 			warnings++;
478 	    }
479             else
480 	    {
481 		topn_specified = true;
482 	    }
483 	}
484 
485 	/* tricky:  remember old value of preset_argc & set preset_argc = 0 */
486 	i = preset_argc;
487 	preset_argc = 0;
488 
489     /* repeat only if we really did the preset arguments */
490     } while (i != 0);
491 
492     /* set constants for username/uid display correctly */
493     if (!do_unames)
494     {
495 	uname_field = "   UID  ";
496 	get_userid = itoa7;
497     }
498 
499     /* initialize the kernel memory interface */
500     if (machine_init(&statics) == -1)
501     {
502 	exit(1);
503     }
504 
505     /* determine sorting order index, if necessary */
506     if (order_name != NULL)
507     {
508 	if ((order_index = string_index(order_name, statics.order_names)) == -1)
509 	{
510 	    const char * const *pp;
511 
512 	    warnx("'%s' is not a recognized sorting order.", order_name);
513 	    fprintf(stderr, "\tTry one of these:");
514 	    pp = statics.order_names;
515 	    while (*pp != NULL)
516 	    {
517 		fprintf(stderr, " %s", *pp++);
518 	    }
519 	    fputc('\n', stderr);
520 	    exit(1);
521 	}
522     }
523 
524     /* initialize termcap */
525     init_termcap(interactive);
526 
527     /* get the string to use for the process area header */
528     header_text = format_header(uname_field);
529 
530     /* initialize display interface */
531     if ((max_topn = display_init(&statics)) == -1)
532     {
533 		errx(4, "can't allocate sufficient memory");
534     }
535 
536     /* print warning if user requested more processes than we can display */
537     if (topn > max_topn)
538     {
539 		warnx("warning: this terminal can only display %d processes.", max_topn);
540 		warnings++;
541     }
542 
543     /* adjust for topn == Infinity */
544     if (topn == Infinity)
545     {
546 	/*
547 	 *  For smart terminals, infinity really means everything that can
548 	 *  be displayed, or Largest.
549 	 *  On dumb terminals, infinity means every process in the system!
550 	 *  We only really want to do that if it was explicitly specified.
551 	 *  This is always the case when "Default_TOPN != Infinity".  But if
552 	 *  topn wasn't explicitly specified and we are on a dumb terminal
553 	 *  and the default is Infinity, then (and only then) we use
554 	 *  "Nominal_TOPN" instead.
555 	 */
556 	topn = smart_terminal ? Largest :
557 		    (topn_specified ? Largest : Nominal_TOPN);
558     }
559 
560     /* set header display accordingly */
561     display_header(topn > 0);
562 
563     /* determine interactive state */
564     if (interactive == 2)
565     {
566 	interactive = smart_terminal;
567     }
568 
569     /* if # of displays not specified, fill it in */
570     if (displays == 0)
571     {
572 	displays = smart_terminal ? Infinity : 1;
573     }
574 
575     /* hold interrupt signals while setting up the screen and the handlers */
576 
577 	sigemptyset(&new_sigmask);
578 	sigaddset(&new_sigmask, SIGINT);
579 	sigaddset(&new_sigmask, SIGQUIT);
580 	sigaddset(&new_sigmask, SIGTSTP);
581 	sigprocmask(SIG_BLOCK, &new_sigmask, &old_sigmask);
582     init_screen();
583     signal(SIGINT, leave);
584     signal(SIGQUIT, leave);
585     signal(SIGTSTP, tstop);
586     signal(SIGWINCH, top_winch);
587     sigprocmask(SIG_SETMASK, &old_sigmask, NULL);
588     if (warnings)
589     {
590 	fputs("....", stderr);
591 	fflush(stderr);
592 	sleep(3 * warnings);
593 	fputc('\n', stderr);
594     }
595 
596 restart:
597 
598     /*
599      *  main loop -- repeat while display count is positive or while it
600      *		indicates infinity (by being -1)
601      */
602 
603     while ((displays == -1) || (displays-- > 0))
604     {
605 	int (*compare)(const void * const, const void * const);
606 
607 
608 	/* get the current stats */
609 	get_system_info(&system_info);
610 
611 	compare = compares[order_index];
612 
613 	/* get the current set of processes */
614 	processes =
615 		get_process_info(&system_info, &ps, compare);
616 
617 	/* display the load averages */
618 	(*d_loadave)(system_info.last_pid,
619 		     system_info.load_avg);
620 
621 	/* display the battery info (if any) */
622 	i_battery(statics.nbatteries, system_info.battery);
623 
624 	/* display the current time */
625 	/* this method of getting the time SHOULD be fairly portable */
626 	time(&curr_time);
627 	i_uptime(&system_info.boottime, &curr_time);
628 	i_timeofday(&curr_time);
629 
630 	/* display process state breakdown */
631 	(*d_procstates)(system_info.p_total,
632 			system_info.procstates);
633 	(*d_cpustates)(system_info.cpustates);
634 
635 	/* display memory stats */
636 	(*d_memory)(system_info.memory);
637 	(*d_arc)(system_info.arc);
638 	(*d_carc)(system_info.carc);
639 
640 	/* display swap stats */
641 	(*d_swap)(system_info.swap);
642 
643 	/* handle message area */
644 	(*d_message)();
645 
646 	/* update the header area */
647 	(*d_header)(header_text);
648 
649 	if (topn > 0)
650 	{
651 	    /* determine number of processes to actually display */
652 	    /* this number will be the smallest of:  active processes,
653 	       number user requested, number current screen accommodates */
654 	    active_procs = system_info.p_pactive;
655 	    if (active_procs > topn)
656 	    {
657 		active_procs = topn;
658 	    }
659 	    if (active_procs > max_topn)
660 	    {
661 		active_procs = max_topn;
662 	    }
663 
664 	    /* now show the top "n" processes. */
665 	    for (i = 0; i < active_procs; i++)
666 	    {
667 		(*d_process)(i, format_next_process(processes, get_userid,
668 			     fmt_flags));
669 	    }
670 	}
671 	else
672 	{
673 	    i = 0;
674 	}
675 
676 	/* do end-screen processing */
677 	u_endscreen(i);
678 
679 	/* now, flush the output buffer */
680 	if (fflush(stdout) != 0)
681 	{
682 	    new_message(MT_standout, " Write error on stdout");
683 	    putchar('\r');
684 	    quit(1);
685 	}
686 
687 	/* only do the rest if we have more displays to show */
688 	if (displays)
689 	{
690 	    /* switch out for new display on smart terminals */
691 	    if (smart_terminal)
692 	    {
693 		if (overstrike)
694 		{
695 		    reset_display();
696 		}
697 		else
698 		{
699 		    d_loadave = u_loadave;
700 		    d_procstates = u_procstates;
701 		    d_cpustates = u_cpustates;
702 		    d_memory = u_memory;
703 		    d_arc = u_arc;
704 		    d_carc = u_carc;
705 		    d_swap = u_swap;
706 		    d_message = u_message;
707 		    d_header = u_header;
708 		    d_process = u_process;
709 		}
710 	    }
711 
712 	    no_command = true;
713 	    if (!interactive)
714 	    {
715 		timeout = delay;
716 		select(0, NULL, NULL, NULL, &timeout);
717 		if (leaveflag) {
718 		    end_screen();
719 		    exit(0);
720 		}
721 	    }
722 	    else while (no_command)
723 	    {
724 		/* assume valid command unless told otherwise */
725 		no_command = false;
726 
727 		/* set up arguments for select with timeout */
728 		FD_ZERO(&readfds);
729 		FD_SET(0, &readfds);		/* for standard input */
730 		timeout = delay;
731 
732 		if (leaveflag) {
733 		    end_screen();
734 		    exit(0);
735 		}
736 
737 		if (tstopflag) {
738 		    /* move to the lower left */
739 		    end_screen();
740 		    fflush(stdout);
741 
742 		    /* default the signal handler action */
743 		    signal(SIGTSTP, SIG_DFL);
744 
745 		    /* unblock the signal and send ourselves one */
746 		    sigsetmask(sigblock(0) & ~(1 << (SIGTSTP - 1)));
747 		    kill(0, SIGTSTP);
748 
749 		    /* reset the signal handler */
750 		    signal(SIGTSTP, tstop);
751 
752 		    /* reinit screen */
753 		    reinit_screen();
754 		    reset_display();
755 		    tstopflag = 0;
756 		    goto restart;
757 		}
758 
759 		if (winchflag) {
760 		    /* reascertain the screen dimensions */
761 		    get_screensize();
762 
763 		    /* tell display to resize */
764 		    max_topn = display_resize();
765 
766 		    /* reset the signal handler */
767 		    signal(SIGWINCH, top_winch);
768 
769 		    reset_display();
770 		    winchflag = 0;
771 		    goto restart;
772 		}
773 
774 		/* wait for either input or the end of the delay period */
775 		sel_ret = select(2, &readfds, NULL, NULL, &timeout);
776 		if (sel_ret < 0 && errno != EINTR)
777 		    quit(0);
778 		if (sel_ret > 0)
779 		{
780 		    int newval;
781 		    const char *errmsg;
782 			const struct command *cptr;
783 
784 		    /* something to read -- clear the message area first */
785 		    clear_message();
786 
787 		    /* now read it and convert to command strchr */
788 		    /* (use "change" as a temporary to hold strchr) */
789 		    if (read(0, &ch, 1) != 1)
790 		    {
791 			/* read error: either 0 or -1 */
792 			new_message(MT_standout, " Read error on stdin");
793 			putchar('\r');
794 			quit(1);
795 		    }
796 			if (ch == '\r' || ch == '\n') {
797 				continue;
798 			}
799 			cptr = all_commands;
800 			while (cptr->c != '\0') {
801 				if (cptr->c == ch) {
802 					break;
803 				}
804 				cptr++;
805 			}
806 			if (cptr->c == '\0') {
807 			    new_message(MT_standout, " Command not understood");
808 			    putchar('\r');
809 				no_command = true;
810 			}
811 			if (overstrike && !cptr->available_to_dumb)
812 			{
813 			    new_message(MT_standout,
814 			    " Command cannot be handled by this terminal");
815 			    putchar('\r');
816 				no_command = true;
817 			}
818 			if (!no_command) {
819 			switch(cptr->id)
820 			{
821 			    case CMD_redraw:	/* redraw screen */
822 				reset_display();
823 				break;
824 
825 			    case CMD_update:	/* merely update display */
826 				break;
827 
828 			    case CMD_quit:
829 				quit(0);
830 				break;
831 
832 			    case CMD_help:
833 				reset_display();
834 				top_clear();
835 				show_help();
836 				top_standout("Hit any key to continue: ");
837 				fflush(stdout);
838 				read(0, &ch, 1);
839 				break;
840 
841 			    case CMD_errors:	/* show errors */
842 				if (error_count() == 0)
843 				{
844 				    new_message(MT_standout,
845 					" Currently no errors to report.");
846 				    putchar('\r');
847 				    no_command = true;
848 				}
849 				else
850 				{
851 				    reset_display();
852 				    top_clear();
853 				    show_errors();
854 				    top_standout("Hit any key to continue: ");
855 				    fflush(stdout);
856 				    read(0, &ch, 1);
857 				}
858 				break;
859 
860 			    case CMD_number:
861 				new_message(MT_standout,
862 				    "Number of processes to show: ");
863 				newval = readline(tempbuf1, 8, true);
864 				if (newval > -1)
865 				{
866 				    if (newval > max_topn)
867 				    {
868 					new_message(MT_standout | MT_delayed,
869 					  " This terminal can only display %d processes.",
870 					  max_topn);
871 					putchar('\r');
872 				    }
873 
874 				    if (newval == 0)
875 				    {
876 					/* inhibit the header */
877 					display_header(false);
878 				    }
879 				    else if (newval > topn && topn == 0)
880 				    {
881 					/* redraw the header */
882 					display_header(true);
883 					d_header = i_header;
884 				    }
885 				    topn = newval;
886 				}
887 				break;
888 
889 			    case CMD_delay:	/* new seconds delay */
890 				new_message(MT_standout, "Seconds to delay: ");
891 				if ((i = readline(tempbuf1, 8, false)) > 0)
892 				{
893 				    double delay_d = strtod(tempbuf1, &nptr);
894 				    if (nptr == tempbuf1 || delay_d <= 0)
895 				    {
896 					new_message(MT_standout, " Invalid delay");
897 					putchar('\r');
898 					no_command = true;
899 				    }
900 				    else
901 				    {
902 					delay.tv_sec = delay_d;
903 					delay.tv_usec = (delay_d - delay.tv_sec) * 1e6;
904 					clear_message();
905 				    }
906 				}
907 				break;
908 
909 			    case CMD_grep: /* grep command name */
910 				new_message(MT_standout,
911 				    "Grep command name (+ for all): ");
912 				if (readline(tempbuf1, sizeof(tempbuf1), false) > 0) {
913 					free(ps.command);
914 					if (tempbuf1[0] == '+' && tempbuf1[1] == '\0') {
915 						ps.command = NULL;
916 					} else if ((ps.command = strdup(tempbuf1)) == NULL)
917 						quit(1);
918 				}
919 				clear_message();
920 				break;
921 
922 			    case CMD_displays:	/* change display count */
923 				new_message(MT_standout,
924 					"Displays to show (currently %s): ",
925 					displays == -1 ? "infinite" :
926 							 itoa(displays));
927 				if ((i = readline(tempbuf1, 10, true)) > 0)
928 				{
929 				    displays = i;
930 				}
931 				else if (i == 0)
932 				{
933 				    quit(0);
934 				}
935 				clear_message();
936 				break;
937 
938 			    case CMD_kill:	/* kill program */
939 				new_message(0, "kill ");
940 				if (readline(tempbuf2, sizeof(tempbuf2), false) > 0)
941 				{
942 				    if ((errmsg = kill_procs(tempbuf2)) != NULL)
943 				    {
944 					new_message(MT_standout, "%s", errmsg);
945 					putchar('\r');
946 					no_command = true;
947 				    }
948 				}
949 				else
950 				{
951 				    clear_message();
952 				}
953 				break;
954 
955 			    case CMD_renice:	/* renice program */
956 				new_message(0, "renice ");
957 				if (readline(tempbuf2, sizeof(tempbuf2), false) > 0)
958 				{
959 				    if ((errmsg = renice_procs(tempbuf2)) != NULL)
960 				    {
961 					new_message(MT_standout, "%s", errmsg);
962 					putchar('\r');
963 					no_command = true;
964 				    }
965 				}
966 				else
967 				{
968 				    clear_message();
969 				}
970 				break;
971 
972 			    case CMD_idletog:
973 				ps.idle = !ps.idle;
974 				new_message(MT_standout | MT_delayed,
975 				    " %sisplaying idle processes.",
976 				    ps.idle ? "D" : "Not d");
977 				putchar('\r');
978 				break;
979 
980 			    case CMD_selftog:
981 				ps.self = !ps.self;
982 				new_message(MT_standout | MT_delayed,
983 				    " %sisplaying self.",
984 				    (ps.self) ? "D" : "Not d");
985 				putchar('\r');
986 				break;
987 
988 			    case CMD_user:
989 				if (handle_user(tempbuf2, sizeof(tempbuf2)))
990 				    no_command = true;
991 				break;
992 
993 			    case CMD_thrtog:
994 				ps.thread = !ps.thread;
995 				new_message(MT_standout | MT_delayed,
996 				    " Displaying threads %s",
997 				    ps.thread ? "separately" : "as a count");
998 				header_text = format_header(uname_field);
999 				reset_display();
1000 				putchar('\r');
1001 				break;
1002 
1003 			    case CMD_toggletid:
1004 				ps.thread_id = !ps.thread_id;
1005 				new_message(MT_standout | MT_delayed,
1006 				    " Displaying %s",
1007 				    ps.thread_id ? "tid" : "pid");
1008 				header_text = format_header(uname_field);
1009 				reset_display();
1010 				putchar('\r');
1011 				break;
1012 
1013 			    case CMD_wcputog:
1014 				ps.wcpu = !ps.wcpu;
1015 				new_message(MT_standout | MT_delayed,
1016 				    " Displaying %s CPU",
1017 				    ps.wcpu ? "weighted" : "raw");
1018 				header_text = format_header(uname_field);
1019 				reset_display();
1020 				putchar('\r');
1021 				break;
1022 			    case CMD_viewtog:
1023 				displaymode = displaymode == DISP_IO ? DISP_CPU : DISP_IO;
1024 				new_message(MT_standout | MT_delayed,
1025 				    " Displaying %s statistics.",
1026 				    displaymode == DISP_IO ? "IO" : "CPU");
1027 				header_text = format_header(uname_field);
1028 				display_header(true);
1029 				d_header = i_header;
1030 				reset_display();
1031 				break;
1032 			    case CMD_viewsys:
1033 				ps.system = !ps.system;
1034 				new_message(MT_standout | MT_delayed,
1035 				    " %sisplaying system processes.",
1036 				    ps.system ? "D" : "Not d");
1037 				break;
1038 			    case CMD_showargs:
1039 				fmt_flags ^= FMT_SHOWARGS;
1040 				show_args = fmt_flags & FMT_SHOWARGS;
1041 				new_message(MT_standout | MT_delayed,
1042 				    " %sisplaying process arguments.",
1043 				    fmt_flags & FMT_SHOWARGS ? "D" : "Not d");
1044 				break;
1045 			    case CMD_order:
1046 				new_message(MT_standout,
1047 				    "Order to sort: ");
1048 				if (readline(tempbuf2, sizeof(tempbuf2), false) > 0)
1049 				{
1050 				  if ((i = string_index(tempbuf2, statics.order_names)) == -1)
1051 					{
1052 					  new_message(MT_standout,
1053 					      " %s: unrecognized sorting order", tempbuf2);
1054 					  no_command = true;
1055 				    }
1056 				    else
1057 				    {
1058 					order_index = i;
1059 				    }
1060 				    putchar('\r');
1061 				}
1062 				else
1063 				{
1064 				    clear_message();
1065 				}
1066 				break;
1067 			    case CMD_jidtog:
1068 				ps.jail = !ps.jail;
1069 				new_message(MT_standout | MT_delayed,
1070 				    " %sisplaying jail ID.",
1071 				    ps.jail ? "D" : "Not d");
1072 				header_text = format_header(uname_field);
1073 				reset_display();
1074 				putchar('\r');
1075 				break;
1076 
1077 			    case CMD_jail:
1078 				new_message(MT_standout,
1079 				    "Jail to show (+ for all): ");
1080 				if (readline(tempbuf2, sizeof(tempbuf2), false) > 0)
1081 				{
1082 				    if (tempbuf2[0] == '+' &&
1083 					tempbuf2[1] == '\0')
1084 				    {
1085 					ps.jid = -1;
1086 				    }
1087 				    else if ((i = jail_getid(tempbuf2)) == -1)
1088 				    {
1089 					new_message(MT_standout,
1090 					    " %s: unknown jail", tempbuf2);
1091 					no_command = true;
1092 				    }
1093 				    else
1094 				    {
1095 					ps.jid = i;
1096 				    }
1097 				    if (ps.jail == 0) {
1098 					    ps.jail = 1;
1099 					    new_message(MT_standout |
1100 						MT_delayed, " Displaying jail "
1101 						"ID.");
1102 					    header_text =
1103 						format_header(uname_field);
1104 					    reset_display();
1105 				    }
1106 				    putchar('\r');
1107 				}
1108 				else
1109 				{
1110 				    clear_message();
1111 				}
1112 				break;
1113 
1114 			    case CMD_kidletog:
1115 				ps.kidle = !ps.kidle;
1116 				new_message(MT_standout | MT_delayed,
1117 				    " %sisplaying system idle process.",
1118 				    ps.kidle ? "D" : "Not d");
1119 				putchar('\r');
1120 				break;
1121 			    case CMD_pcputog:
1122 				pcpu_stats = !pcpu_stats;
1123 				new_message(MT_standout | MT_delayed,
1124 				    " Displaying %sCPU statistics.",
1125 				    pcpu_stats ? "per-" : "global ");
1126 				toggle_pcpustats();
1127 				max_topn = display_updatecpus(&statics);
1128 				reset_display();
1129 				putchar('\r');
1130 				break;
1131 			    case CMD_swaptog:
1132 				ps.swap = !ps.swap;
1133 				new_message(MT_standout | MT_delayed,
1134 				    " %sisplaying per-process swap usage.",
1135 				    ps.swap ? "D" : "Not d");
1136 				header_text = format_header(uname_field);
1137 				reset_display();
1138 				putchar('\r');
1139 				break;
1140 			    case CMD_pid:
1141 				new_message(MT_standout,
1142 					"Process id to show (+ for all): ");
1143 				if (readline(tempbuf2, sizeof(tempbuf2), false) > 0) {
1144 					if (tempbuf2[0] == '+' &&
1145                    			    tempbuf2[1] == '\0') {
1146 						ps.pid = (pid_t)-1;
1147 					} else {
1148 						unsigned long long num;
1149 						const char *errstr;
1150 
1151 						num = strtonum(tempbuf2, 0, INT_MAX,
1152 							&errstr);
1153 						if (errstr != NULL || !find_pid(num)) {
1154 							new_message(MT_standout,
1155 								" %s: unknown pid",
1156 								tempbuf2);
1157 							no_command = true;
1158 						} else {
1159 							ps.pid = (pid_t)num;
1160 						}
1161 					}
1162 					putchar('\r');
1163 				} else
1164 					clear_message();
1165 				break;
1166 			    case CMD_NONE:
1167 					assert(false && "reached switch without command");
1168 			}
1169 			}
1170 		    }
1171 
1172 		    /* flush out stuff that may have been written */
1173 		    fflush(stdout);
1174 		}
1175 	    }
1176     }
1177 
1178 #ifdef DEBUG
1179     fclose(debug);
1180 #endif
1181     quit(0);
1182 }
1183 
1184 /*
1185  *  reset_display() - reset all the display routine pointers so that entire
1186  *	screen will get redrawn.
1187  */
1188 
1189 static void
1190 reset_display(void)
1191 {
1192     d_loadave    = i_loadave;
1193     d_procstates = i_procstates;
1194     d_cpustates  = i_cpustates;
1195     d_memory     = i_memory;
1196     d_arc        = i_arc;
1197     d_carc       = i_carc;
1198     d_swap       = i_swap;
1199     d_message	 = i_message;
1200     d_header	 = i_header;
1201     d_process	 = i_process;
1202 }
1203 
1204 /*
1205  *  signal handlers
1206  */
1207 
1208 static sigret_t
1209 leave(int i __unused)	/* exit under normal conditions -- INT handler */
1210 {
1211 
1212     leaveflag = 1;
1213 }
1214 
1215 static sigret_t
1216 tstop(int i __unused)	/* SIGTSTP handler */
1217 {
1218 
1219     tstopflag = 1;
1220 }
1221 
1222 static sigret_t
1223 top_winch(int i __unused)		/* SIGWINCH handler */
1224 {
1225 
1226     winchflag = 1;
1227 }
1228 
1229 void __dead2
1230 quit(int status)		/* exit under duress */
1231 {
1232     end_screen();
1233     exit(status);
1234 }
1235