xref: /freebsd/usr.bin/top/display.c (revision ce6a89e27cd190313be39bb479880aeda4778436)
1 /*
2  *  Top users/processes display for Unix
3  *  Version 3
4  *
5  *  This program may be freely redistributed,
6  *  but this entire comment MUST remain intact.
7  *
8  *  Copyright (c) 1984, 1989, William LeFebvre, Rice University
9  *  Copyright (c) 1989, 1990, 1992, William LeFebvre, Northwestern University
10  *
11  * $FreeBSD$
12  */
13 
14 /*
15  *  This file contains the routines that display information on the screen.
16  *  Each section of the screen has two routines:  one for initially writing
17  *  all constant and dynamic text, and one for only updating the text that
18  *  changes.  The prefix "i_" is used on all the "initial" routines and the
19  *  prefix "u_" is used for all the "updating" routines.
20  *
21  *  ASSUMPTIONS:
22  *        None of the "i_" routines use any of the termcap capabilities.
23  *        In this way, those routines can be safely used on terminals that
24  *        have minimal (or nonexistant) terminal capabilities.
25  *
26  *        The routines are called in this order:  *_loadave, i_timeofday,
27  *        *_procstates, *_cpustates, *_memory, *_message, *_header,
28  *        *_process, u_endscreen.
29  */
30 
31 #include <sys/cdefs.h>
32 #include <sys/resource.h>
33 #include <sys/time.h>
34 
35 #include <assert.h>
36 #include <ctype.h>
37 #include <err.h>
38 #include <stdarg.h>
39 #include <stdbool.h>
40 #include <stdlib.h>
41 #include <stdio.h>
42 #include <string.h>
43 #include <termcap.h>
44 #include <time.h>
45 #include <unistd.h>
46 
47 #include "screen.h"		/* interface to screen package */
48 #include "layout.h"		/* defines for screen position layout */
49 #include "display.h"
50 #include "top.h"
51 #include "machine.h"		/* we should eliminate this!!! */
52 #include "utils.h"
53 
54 #ifdef DEBUG
55 FILE *debug;
56 #endif
57 
58 static int lmpid = 0;
59 static int last_hi = 0;		/* used in u_process and u_endscreen */
60 static int lastline = 0;
61 
62 #define lineindex(l) ((l)*screen_width)
63 
64 
65 /* things initialized by display_init and used thruout */
66 
67 /* buffer of proc information lines for display updating */
68 static char *screenbuf = NULL;
69 
70 static const char * const *procstate_names;
71 static const char * const *cpustate_names;
72 static const char * const *memory_names;
73 static const char * const *arc_names;
74 static const char * const *carc_names;
75 static const char * const *swap_names;
76 
77 static int num_procstates;
78 static int num_cpustates;
79 static int num_memory;
80 static int num_swap;
81 
82 static int *lprocstates;
83 static int *lcpustates;
84 static int *lmemory;
85 static int *lswap;
86 
87 static int num_cpus;
88 static int *cpustate_columns;
89 static int cpustate_total_length;
90 static int cpustates_column;
91 
92 static enum { OFF, ON, ERASE } header_status = ON;
93 
94 static void summary_format(char *, int *, const char * const *);
95 static void line_update(char *, char *, int, int);
96 
97 static int setup_buffer_bufsiz = 0;
98 static char * setup_buffer(char *, int);
99 
100 int  x_lastpid =	10;
101 int  y_lastpid =	0;
102 int  x_loadave =	33;
103 int  x_loadave_nompid =	15;
104 int  y_loadave =	0;
105 int  x_procstate =	0;
106 int  y_procstate =	1;
107 int  x_brkdn =		15;
108 int  y_brkdn =		1;
109 int  x_mem =		5;
110 int  y_mem =		3;
111 int  x_arc =		5;
112 int  y_arc =		4;
113 int  x_carc =		5;
114 int  y_carc =		5;
115 int  x_swap =		6;
116 int  y_swap =		4;
117 int  y_message =	5;
118 int  x_header =		0;
119 int  y_header =		6;
120 int  x_idlecursor =	0;
121 int  y_idlecursor =	5;
122 int  y_procs =		7;
123 
124 int  y_cpustates =	2;
125 int  Header_lines =	7;
126 
127 int
128 display_resize(void)
129 {
130     int lines;
131 
132     /* first, deallocate any previous buffer that may have been there */
133     if (screenbuf != NULL)
134     {
135 	free(screenbuf);
136     }
137 
138     /* calculate the current dimensions */
139     /* if operating in "dumb" mode, we only need one line */
140     lines = smart_terminal ? screen_length - Header_lines : 1;
141 
142     if (lines < 0)
143 	lines = 0;
144 
145     /* now, allocate space for the screen buffer */
146     screenbuf = calloc(lines, screen_width);
147     if (screenbuf == NULL)
148     {
149 	/* oops! */
150 	return(-1);
151     }
152 
153     /* return number of lines available */
154     /* for dumb terminals, pretend like we can show any amount */
155     return(smart_terminal ? lines : Largest);
156 }
157 
158 int
159 display_updatecpus(struct statics *statics)
160 {
161     int lines;
162     int i;
163 
164     /* call resize to do the dirty work */
165     lines = display_resize();
166     if (pcpu_stats)
167 		num_cpus = statics->ncpus;
168     else
169 		num_cpus = 1;
170     cpustates_column = 5;	/* CPU: */
171     if (num_cpus > 1) {
172 		cpustates_column += 1 + digits(num_cpus); /* CPU #: */
173 	}
174 
175     /* fill the "last" array with all -1s, to insure correct updating */
176 	for (i = 0; i < num_cpustates * num_cpus; ++i) {
177 		lcpustates[i] = -1;
178     }
179 
180     return(lines);
181 }
182 
183 int
184 display_init(struct statics * statics)
185 {
186     int lines;
187     const char * const *pp;
188     int *ip;
189     int i;
190 
191     lines = display_updatecpus(statics);
192 
193     /* only do the rest if we need to */
194     if (lines > -1)
195     {
196 	/* save pointers and allocate space for names */
197 	procstate_names = statics->procstate_names;
198 	num_procstates = 8;
199 	assert(num_procstates > 0);
200 	lprocstates = calloc(num_procstates, sizeof(int));
201 
202 	cpustate_names = statics->cpustate_names;
203 
204 	swap_names = statics->swap_names;
205 	num_swap = 7;
206 	assert(num_swap > 0);
207 	lswap = calloc(num_swap, sizeof(int));
208 	num_cpustates = CPUSTATES;
209 	assert(num_cpustates > 0);
210 	lcpustates = calloc(num_cpustates * sizeof(int), statics->ncpus);
211 	cpustate_columns = calloc(num_cpustates, sizeof(int));
212 
213 	memory_names = statics->memory_names;
214 	num_memory = 7;
215 	assert(num_memory > 0);
216 	lmemory = calloc(num_memory, sizeof(int));
217 
218 	arc_names = statics->arc_names;
219 	carc_names = statics->carc_names;
220 
221 	/* calculate starting columns where needed */
222 	cpustate_total_length = 0;
223 	pp = cpustate_names;
224 	ip = cpustate_columns;
225 	while (*pp != NULL)
226 	{
227 	    *ip++ = cpustate_total_length;
228 	    if ((i = strlen(*pp++)) > 0)
229 	    {
230 		cpustate_total_length += i + 8;
231 	    }
232 	}
233     }
234 
235     /* return number of lines available */
236     return(lines);
237 }
238 
239 void
240 i_loadave(int mpid, double avenrun[])
241 {
242     int i;
243 
244     /* i_loadave also clears the screen, since it is first */
245     top_clear();
246 
247     /* mpid == -1 implies this system doesn't have an _mpid */
248     if (mpid != -1)
249     {
250 	printf("last pid: %5d;  ", mpid);
251     }
252 
253     printf("load averages");
254 
255     for (i = 0; i < 3; i++)
256     {
257 	printf("%c %5.2f",
258 	    i == 0 ? ':' : ',',
259 	    avenrun[i]);
260     }
261     lmpid = mpid;
262 }
263 
264 void
265 u_loadave(int mpid, double *avenrun)
266 {
267     int i;
268 
269     if (mpid != -1)
270     {
271 	/* change screen only when value has really changed */
272 	if (mpid != lmpid)
273 	{
274 	    Move_to(x_lastpid, y_lastpid);
275 	    printf("%5d", mpid);
276 	    lmpid = mpid;
277 	}
278 
279 	/* i remembers x coordinate to move to */
280 	i = x_loadave;
281     }
282     else
283     {
284 	i = x_loadave_nompid;
285     }
286 
287     /* move into position for load averages */
288     Move_to(i, y_loadave);
289 
290     /* display new load averages */
291     /* we should optimize this and only display changes */
292     for (i = 0; i < 3; i++)
293     {
294 	printf("%s%5.2f",
295 	    i == 0 ? "" : ", ",
296 	    avenrun[i]);
297     }
298 }
299 
300 void
301 i_timeofday(time_t *tod)
302 {
303     /*
304      *  Display the current time.
305      *  "ctime" always returns a string that looks like this:
306      *
307      *	Sun Sep 16 01:03:52 1973
308      *      012345678901234567890123
309      *	          1         2
310      *
311      *  We want indices 11 thru 18 (length 8).
312      */
313 
314     if (smart_terminal)
315     {
316 	Move_to(screen_width - 8, 0);
317     }
318     else
319     {
320 	fputs("    ", stdout);
321     }
322 #ifdef DEBUG
323     {
324 	char *foo;
325 	foo = ctime(tod);
326 	fputs(foo, stdout);
327     }
328 #endif
329     printf("%-8.8s\n", &(ctime(tod)[11]));
330     lastline = 1;
331 }
332 
333 static int ltotal = 0;
334 static char *procstates_buffer = NULL;
335 
336 /*
337  *  *_procstates(total, brkdn, names) - print the process summary line
338  *
339  *  Assumptions:  cursor is at the beginning of the line on entry
340  *		  lastline is valid
341  */
342 
343 void
344 i_procstates(int total, int *brkdn)
345 {
346     int i;
347 
348     procstates_buffer = setup_buffer(procstates_buffer, 0);
349 
350     /* write current number of processes and remember the value */
351     printf("%d %s:", total, ps.thread ? "threads" : "processes");
352     ltotal = total;
353 
354     /* put out enough spaces to get to column 15 */
355     i = digits(total);
356     while (i++ < (ps.thread ? 6 : 4))
357     {
358 	putchar(' ');
359     }
360 
361     /* format and print the process state summary */
362     summary_format(procstates_buffer, brkdn, procstate_names);
363     fputs(procstates_buffer, stdout);
364 
365     /* save the numbers for next time */
366     memcpy(lprocstates, brkdn, num_procstates * sizeof(int));
367 }
368 
369 void
370 u_procstates(int total, int *brkdn)
371 {
372     static char *new = NULL;
373     int i;
374 
375     new = setup_buffer(new, 0);
376 
377     /* update number of processes only if it has changed */
378     if (ltotal != total)
379     {
380 	/* move and overwrite */
381 	if (x_procstate == 0) {
382 	    Move_to(x_procstate, y_procstate);
383 	}
384 	else {
385 	    /* cursor is already there...no motion needed */
386 	    assert(lastline == 1);
387 	}
388 	printf("%d", total);
389 
390 	/* if number of digits differs, rewrite the label */
391 	if (digits(total) != digits(ltotal))
392 	{
393 	    printf(" %s:", ps.thread ? "threads" : "processes");
394 	    /* put out enough spaces to get to column 15 */
395 	    i = digits(total);
396 	    while (i++ < (ps.thread ? 6 : 4))
397 	    {
398 		putchar(' ');
399 	    }
400 	    /* cursor may end up right where we want it!!! */
401 	}
402 
403 	/* save new total */
404 	ltotal = total;
405     }
406 
407     /* see if any of the state numbers has changed */
408     if (memcmp(lprocstates, brkdn, num_procstates * sizeof(int)) != 0)
409     {
410 	/* format and update the line */
411 	summary_format(new, brkdn, procstate_names);
412 	line_update(procstates_buffer, new, x_brkdn, y_brkdn);
413 	memcpy(lprocstates, brkdn, num_procstates * sizeof(int));
414     }
415 }
416 
417 void
418 i_cpustates(int *states)
419 {
420     int i = 0;
421     int value;
422     const char * const *names;
423     const char *thisname;
424     int *hstates = states;
425     int cpu;
426 
427 for (cpu = 0; cpu < num_cpus; cpu++) {
428     names = cpustate_names;
429 
430     /* print tag and bump lastline */
431     if (num_cpus == 1)
432 	printf("\nCPU: ");
433     else {
434 	value = printf("\nCPU %d: ", cpu);
435 	while (value++ <= cpustates_column)
436 		printf(" ");
437     }
438     lastline++;
439 
440     /* now walk thru the names and print the line */
441     while ((thisname = *names++) != NULL)
442     {
443 	if (*thisname != '\0')
444 	{
445 	    /* retrieve the value and remember it */
446 	    value = *states++;
447 
448 	    /* if percentage is >= 1000, print it as 100% */
449 	    printf((value >= 1000 ? "%s%4.0f%% %s" : "%s%4.1f%% %s"),
450 		   (i++ % num_cpustates) == 0 ? "" : ", ",
451 		   ((float)value)/10.,
452 		   thisname);
453 	}
454     }
455 }
456 
457     /* copy over values into "last" array */
458     states = hstates;
459     memcpy(lcpustates, states, num_cpustates * sizeof(int) * num_cpus);
460 }
461 
462 void
463 u_cpustates(int *states)
464 {
465     int value;
466     const char * const *names;
467     const char *thisname;
468     int *hstates = states;
469     int *lp;
470     int *colp;
471     int cpu;
472 
473 for (cpu = 0; cpu < num_cpus; cpu++) {
474     names = cpustate_names;
475 
476     Move_to(cpustates_column, y_cpustates + cpu);
477     lastline = y_cpustates + cpu;
478     lp = lcpustates + (cpu * num_cpustates);
479     colp = cpustate_columns;
480 
481     /* we could be much more optimal about this */
482     while ((thisname = *names++) != NULL)
483     {
484 	if (*thisname != '\0')
485 	{
486 	    /* did the value change since last time? */
487 	    if (*lp != *states)
488 	    {
489 		/* yes, move and change */
490 		Move_to(cpustates_column + *colp, y_cpustates + cpu);
491 		lastline = y_cpustates + cpu;
492 
493 		/* retrieve value and remember it */
494 		value = *states;
495 
496 		/* if percentage is >= 1000, print it as 100% */
497 		printf((value >= 1000 ? "%4.0f" : "%4.1f"),
498 		       ((double)value)/10.);
499 
500 		/* remember it for next time */
501 		*lp = value;
502 	    }
503 	}
504 
505 	/* increment and move on */
506 	lp++;
507 	states++;
508 	colp++;
509     }
510 }
511 
512     states = hstates;
513 }
514 
515 void
516 z_cpustates(void)
517 {
518     int i = 0;
519     const char * const *names;
520     const char *thisname;
521     int cpu, value;
522 
523     for (cpu = 0; cpu < num_cpus; cpu++) {
524 	    names = cpustate_names;
525 
526 	    /* show tag and bump lastline */
527 	    if (num_cpus == 1)
528 		    printf("\nCPU: ");
529 	    else {
530 		    value = printf("\nCPU %d: ", cpu);
531 		    while (value++ <= cpustates_column)
532 			    printf(" ");
533 	    }
534 	    lastline++;
535 
536 	    while ((thisname = *names++) != NULL)
537 	    {
538 		    if (*thisname != '\0')
539 		    {
540 			    printf("%s    %% %s", (i++ % num_cpustates) == 0 ? "" : ", ", thisname);
541 		    }
542 	    }
543     }
544 
545     /* fill the "last" array with all -1s, to insure correct updating */
546 	for (i = 0; i < num_cpustates * num_cpus; ++i) {
547 		lcpustates[i] = -1;
548     }
549 }
550 
551 /*
552  *  *_memory(stats) - print "Memory: " followed by the memory summary string
553  *
554  *  Assumptions:  cursor is on "lastline"
555  *                for i_memory ONLY: cursor is on the previous line
556  */
557 
558 static char *memory_buffer = NULL;
559 
560 void
561 i_memory(int *stats)
562 {
563     memory_buffer = setup_buffer(memory_buffer, 0);
564 
565     fputs("\nMem: ", stdout);
566     lastline++;
567 
568     /* format and print the memory summary */
569     summary_format(memory_buffer, stats, memory_names);
570     fputs(memory_buffer, stdout);
571 }
572 
573 void
574 u_memory(int *stats)
575 {
576     static char *new = NULL;
577 
578     new = setup_buffer(new, 0);
579 
580     /* format the new line */
581     summary_format(new, stats, memory_names);
582     line_update(memory_buffer, new, x_mem, y_mem);
583 }
584 
585 /*
586  *  *_arc(stats) - print "ARC: " followed by the ARC summary string
587  *
588  *  Assumptions:  cursor is on "lastline"
589  *                for i_arc ONLY: cursor is on the previous line
590  */
591 static char *arc_buffer = NULL;
592 
593 void
594 i_arc(int *stats)
595 {
596     arc_buffer = setup_buffer(arc_buffer, 0);
597 
598     if (arc_names == NULL)
599 	return;
600 
601     fputs("\nARC: ", stdout);
602     lastline++;
603 
604     /* format and print the memory summary */
605     summary_format(arc_buffer, stats, arc_names);
606     fputs(arc_buffer, stdout);
607 }
608 
609 void
610 u_arc(int *stats)
611 {
612     static char *new = NULL;
613 
614     new = setup_buffer(new, 0);
615 
616     if (arc_names == NULL)
617 	return;
618 
619     /* format the new line */
620     summary_format(new, stats, arc_names);
621     line_update(arc_buffer, new, x_arc, y_arc);
622 }
623 
624 
625 /*
626  *  *_carc(stats) - print "Compressed ARC: " followed by the summary string
627  *
628  *  Assumptions:  cursor is on "lastline"
629  *                for i_carc ONLY: cursor is on the previous line
630  */
631 static char *carc_buffer = NULL;
632 
633 void
634 i_carc(int *stats)
635 {
636     carc_buffer = setup_buffer(carc_buffer, 0);
637 
638     if (carc_names == NULL)
639 	return;
640 
641     fputs("\n     ", stdout);
642     lastline++;
643 
644     /* format and print the memory summary */
645     summary_format(carc_buffer, stats, carc_names);
646     fputs(carc_buffer, stdout);
647 }
648 
649 void
650 u_carc(int *stats)
651 {
652     static char *new = NULL;
653 
654     new = setup_buffer(new, 0);
655 
656     if (carc_names == NULL)
657 	return;
658 
659     /* format the new line */
660     summary_format(new, stats, carc_names);
661     line_update(carc_buffer, new, x_carc, y_carc);
662 }
663 
664 /*
665  *  *_swap(stats) - print "Swap: " followed by the swap summary string
666  *
667  *  Assumptions:  cursor is on "lastline"
668  *                for i_swap ONLY: cursor is on the previous line
669  */
670 
671 static char *swap_buffer = NULL;
672 
673 void
674 i_swap(int *stats)
675 {
676     swap_buffer = setup_buffer(swap_buffer, 0);
677 
678     if (swap_names == NULL)
679 	    return;
680 
681     fputs("\nSwap: ", stdout);
682     lastline++;
683 
684     /* format and print the swap summary */
685     summary_format(swap_buffer, stats, swap_names);
686     fputs(swap_buffer, stdout);
687 }
688 
689 void
690 u_swap(int *stats)
691 {
692     static char *new = NULL;
693 
694     new = setup_buffer(new, 0);
695 
696     if (swap_names == NULL)
697 	    return;
698 
699     /* format the new line */
700     summary_format(new, stats, swap_names);
701     line_update(swap_buffer, new, x_swap, y_swap);
702 }
703 
704 /*
705  *  *_message() - print the next pending message line, or erase the one
706  *                that is there.
707  *
708  *  Note that u_message is (currently) the same as i_message.
709  *
710  *  Assumptions:  lastline is consistent
711  */
712 
713 /*
714  *  i_message is funny because it gets its message asynchronously (with
715  *	respect to screen updates).
716  */
717 
718 #define NEXT_MSG_ADDLEN 5
719 static char *next_msg = NULL;
720 static int msglen = 0;
721 /* Invariant: msglen is always the length of the message currently displayed
722    on the screen (even when next_msg doesn't contain that message). */
723 
724 void
725 i_message(void)
726 {
727     next_msg = setup_buffer(next_msg, NEXT_MSG_ADDLEN);
728 
729     while (lastline < y_message)
730     {
731 	fputc('\n', stdout);
732 	lastline++;
733     }
734     if (next_msg[0] != '\0')
735     {
736 	top_standout(next_msg);
737 	msglen = strlen(next_msg);
738 	next_msg[0] = '\0';
739     }
740     else if (msglen > 0)
741     {
742 	(void) clear_eol(msglen);
743 	msglen = 0;
744     }
745 }
746 
747 void
748 u_message(void)
749 {
750     i_message();
751 }
752 
753 static int header_length;
754 
755 /*
756  * Trim a header string to the current display width and return a newly
757  * allocated area with the trimmed header.
758  */
759 
760 char *
761 trim_header(const char *text)
762 {
763 	char *s;
764 	int width;
765 
766 	s = NULL;
767 	width = screen_width;
768 	header_length = strlen(text);
769 	if (header_length >= width) {
770 		s = strndup(text, width);
771 		if (s == NULL)
772 			return (NULL);
773 	}
774 	return (s);
775 }
776 
777 /*
778  *  *_header(text) - print the header for the process area
779  *
780  *  Assumptions:  cursor is on the previous line and lastline is consistent
781  */
782 
783 void
784 i_header(const char *text)
785 {
786     char *s;
787 
788     s = trim_header(text);
789     if (s != NULL)
790 	text = s;
791 
792     if (header_status == ON)
793     {
794 	putchar('\n');
795 	fputs(text, stdout);
796 	lastline++;
797     }
798     else if (header_status == ERASE)
799     {
800 	header_status = OFF;
801     }
802     free(s);
803 }
804 
805 void
806 u_header(const char *text __unused)
807 {
808 
809     if (header_status == ERASE)
810     {
811 	putchar('\n');
812 	lastline++;
813 	clear_eol(header_length);
814 	header_status = OFF;
815     }
816 }
817 
818 /*
819  *  *_process(line, thisline) - print one process line
820  *
821  *  Assumptions:  lastline is consistent
822  */
823 
824 void
825 i_process(int line, char *thisline)
826 {
827     char *p;
828     char *base;
829 
830     /* make sure we are on the correct line */
831     while (lastline < y_procs + line)
832     {
833 	putchar('\n');
834 	lastline++;
835     }
836 
837     /* truncate the line to conform to our current screen width */
838     int len = strlen(thisline);
839     if (screen_width < len)
840     {
841 	thisline[screen_width] = '\0';
842     }
843 
844     /* write the line out */
845     fputs(thisline, stdout);
846 
847     /* copy it in to our buffer */
848     base = smart_terminal ? screenbuf + lineindex(line) : screenbuf;
849     p = stpcpy(base, thisline);
850 
851     /* zero fill the rest of it */
852     if (p - base < screen_width)
853     {
854 	memset(p, 0, screen_width - (p - base));
855     }
856 }
857 
858 void
859 u_process(int line, char *newline)
860 {
861     char *optr;
862     int screen_line = line + Header_lines;
863     char *bufferline;
864 
865     /* remember a pointer to the current line in the screen buffer */
866     bufferline = &screenbuf[lineindex(line)];
867 
868     /* truncate the line to conform to our current screen width */
869     int len = strlen(newline);
870     if (screen_width < len)
871     {
872 	newline[screen_width] = '\0';
873     }
874 
875     /* is line higher than we went on the last display? */
876     if (line >= last_hi)
877     {
878 	/* yes, just ignore screenbuf and write it out directly */
879 	/* get positioned on the correct line */
880 	if (screen_line - lastline == 1)
881 	{
882 	    putchar('\n');
883 	    lastline++;
884 	}
885 	else
886 	{
887 	    Move_to(0, screen_line);
888 	    lastline = screen_line;
889 	}
890 
891 	/* now write the line */
892 	fputs(newline, stdout);
893 
894 	/* copy it in to the buffer */
895 	optr = stpcpy(bufferline, newline);
896 
897 	/* zero fill the rest of it */
898 	if (optr - bufferline < screen_width)
899 	{
900 	    memset(optr, 0, screen_width - (optr - bufferline));
901 	}
902     }
903     else
904     {
905 	line_update(bufferline, newline, 0, line + Header_lines);
906     }
907 }
908 
909 void
910 u_endscreen(int hi)
911 {
912     int screen_line = hi + Header_lines;
913     int i;
914 
915     if (smart_terminal)
916     {
917 	if (hi < last_hi)
918 	{
919 	    /* need to blank the remainder of the screen */
920 	    /* but only if there is any screen left below this line */
921 	    if (lastline + 1 < screen_length)
922 	    {
923 		/* efficiently move to the end of currently displayed info */
924 		if (screen_line - lastline < 5)
925 		{
926 		    while (lastline < screen_line)
927 		    {
928 			putchar('\n');
929 			lastline++;
930 		    }
931 		}
932 		else
933 		{
934 		    Move_to(0, screen_line);
935 		    lastline = screen_line;
936 		}
937 
938 		if (clear_to_end)
939 		{
940 		    /* we can do this the easy way */
941 		    putcap(clear_to_end);
942 		}
943 		else
944 		{
945 		    /* use clear_eol on each line */
946 		    i = hi;
947 		    while ((void) clear_eol(strlen(&screenbuf[lineindex(i++)])), i < last_hi)
948 		    {
949 			putchar('\n');
950 		    }
951 		}
952 	    }
953 	}
954 	last_hi = hi;
955 
956 	/* move the cursor to a pleasant place */
957 	Move_to(x_idlecursor, y_idlecursor);
958 	lastline = y_idlecursor;
959     }
960     else
961     {
962 	/* separate this display from the next with some vertical room */
963 	fputs("\n\n", stdout);
964     }
965 }
966 
967 void
968 display_header(int t)
969 {
970 
971     if (t)
972     {
973 	header_status = ON;
974     }
975     else if (header_status == ON)
976     {
977 	header_status = ERASE;
978     }
979 }
980 
981 void
982 new_message(int type, const char *msgfmt, ...)
983 {
984     va_list args;
985     size_t i;
986 
987     va_start(args, msgfmt);
988 
989     /* first, format the message */
990     vsnprintf(next_msg, setup_buffer_bufsiz + NEXT_MSG_ADDLEN,
991 		    msgfmt, args);
992 
993     va_end(args);
994 
995     if (msglen > 0)
996     {
997 	/* message there already -- can we clear it? */
998 	if (!overstrike)
999 	{
1000 	    /* yes -- write it and clear to end */
1001 	    i = strlen(next_msg);
1002 	    if ((type & MT_delayed) == 0)
1003 	    {
1004 			if (type & MT_standout) {
1005 				top_standout(next_msg);
1006 			} else {
1007 				fputs(next_msg, stdout);
1008 			}
1009 			clear_eol(msglen - i);
1010 			msglen = i;
1011 			next_msg[0] = '\0';
1012 	    }
1013 	}
1014     }
1015     else
1016     {
1017 	if ((type & MT_delayed) == 0)
1018 	{
1019 		if (type & MT_standout) {
1020 			top_standout(next_msg);
1021 		} else {
1022 			fputs(next_msg, stdout);
1023 		}
1024 	    msglen = strlen(next_msg);
1025 	    next_msg[0] = '\0';
1026 	}
1027     }
1028 }
1029 
1030 void
1031 clear_message(void)
1032 {
1033     if (clear_eol(msglen) == 1)
1034     {
1035 	putchar('\r');
1036     }
1037 }
1038 
1039 int
1040 readline(char *buffer, int size, int numeric)
1041 {
1042     char *ptr = buffer;
1043     char ch;
1044     char cnt = 0;
1045     char maxcnt = 0;
1046 
1047     /* allow room for null terminator */
1048     size -= 1;
1049 
1050     /* read loop */
1051     while ((fflush(stdout), read(0, ptr, 1) > 0))
1052     {
1053 	/* newline means we are done */
1054 	if ((ch = *ptr) == '\n' || ch == '\r')
1055 	{
1056 	    break;
1057 	}
1058 
1059 	/* handle special editing characters */
1060 	if (ch == ch_kill)
1061 	{
1062 	    /* kill line -- account for overstriking */
1063 	    if (overstrike)
1064 	    {
1065 		msglen += maxcnt;
1066 	    }
1067 
1068 	    /* return null string */
1069 	    *buffer = '\0';
1070 	    putchar('\r');
1071 	    return(-1);
1072 	}
1073 	else if (ch == ch_erase)
1074 	{
1075 	    /* erase previous character */
1076 	    if (cnt <= 0)
1077 	    {
1078 		/* none to erase! */
1079 		putchar('\7');
1080 	    }
1081 	    else
1082 	    {
1083 		fputs("\b \b", stdout);
1084 		ptr--;
1085 		cnt--;
1086 	    }
1087 	}
1088 	/* check for character validity and buffer overflow */
1089 	else if (cnt == size || (numeric && !isdigit(ch)) ||
1090 		!isprint(ch))
1091 	{
1092 	    /* not legal */
1093 	    putchar('\7');
1094 	}
1095 	else
1096 	{
1097 	    /* echo it and store it in the buffer */
1098 	    putchar(ch);
1099 	    ptr++;
1100 	    cnt++;
1101 	    if (cnt > maxcnt)
1102 	    {
1103 		maxcnt = cnt;
1104 	    }
1105 	}
1106     }
1107 
1108     /* all done -- null terminate the string */
1109     *ptr = '\0';
1110 
1111     /* account for the extra characters in the message area */
1112     /* (if terminal overstrikes, remember the furthest they went) */
1113     msglen += overstrike ? maxcnt : cnt;
1114 
1115     /* return either inputted number or string length */
1116     putchar('\r');
1117     return(cnt == 0 ? -1 : numeric ? atoi(buffer) : cnt);
1118 }
1119 
1120 /* internal support routines */
1121 
1122 static void
1123 summary_format(char *str, int *numbers, const char * const *names)
1124 {
1125     char *p;
1126     int num;
1127     const char *thisname;
1128     char rbuf[6];
1129 
1130     /* format each number followed by its string */
1131     p = str;
1132     while ((thisname = *names++) != NULL)
1133     {
1134 	/* get the number to format */
1135 	num = *numbers++;
1136 
1137 	/* display only non-zero numbers */
1138 	if (num > 0)
1139 	{
1140 	    /* is this number in kilobytes? */
1141 	    if (thisname[0] == 'K')
1142 	    {
1143 		/* yes: format it as a memory value */
1144 		p = stpcpy(p, format_k(num));
1145 
1146 		/* skip over the K, since it was included by format_k */
1147 		p = stpcpy(p, thisname+1);
1148 	    }
1149 	    /* is this number a ratio? */
1150 	    else if (thisname[0] == ':')
1151 	    {
1152 		(void) snprintf(rbuf, sizeof(rbuf), "%.2f",
1153 		    (float)*(numbers - 2) / (float)num);
1154 		p = stpcpy(p, rbuf);
1155 		p = stpcpy(p, thisname);
1156 	    }
1157 	    else
1158 	    {
1159 		p = stpcpy(p, itoa(num));
1160 		p = stpcpy(p, thisname);
1161 	    }
1162 	}
1163 
1164 	/* ignore negative numbers, but display corresponding string */
1165 	else if (num < 0)
1166 	{
1167 	    p = stpcpy(p, thisname);
1168 	}
1169     }
1170 
1171     /* if the last two characters in the string are ", ", delete them */
1172     p -= 2;
1173     if (p >= str && p[0] == ',' && p[1] == ' ')
1174     {
1175 	*p = '\0';
1176     }
1177 }
1178 
1179 static void
1180 line_update(char *old, char *new, int start, int line)
1181 {
1182     int ch;
1183     int diff;
1184     int newcol = start + 1;
1185     int lastcol = start;
1186     char cursor_on_line = false;
1187     char *current;
1188 
1189     /* compare the two strings and only rewrite what has changed */
1190     current = old;
1191 #ifdef DEBUG
1192     fprintf(debug, "line_update, starting at %d\n", start);
1193     fputs(old, debug);
1194     fputc('\n', debug);
1195     fputs(new, debug);
1196     fputs("\n-\n", debug);
1197 #endif
1198 
1199     /* start things off on the right foot		    */
1200     /* this is to make sure the invariants get set up right */
1201     if ((ch = *new++) != *old)
1202     {
1203 	if (line - lastline == 1 && start == 0)
1204 	{
1205 	    putchar('\n');
1206 	}
1207 	else
1208 	{
1209 	    Move_to(start, line);
1210 	}
1211 	cursor_on_line = true;
1212 	putchar(ch);
1213 	*old = ch;
1214 	lastcol = start + 1;
1215     }
1216     old++;
1217 
1218     /*
1219      *  main loop -- check each character.  If the old and new aren't the
1220      *	same, then update the display.  When the distance from the
1221      *	current cursor position to the new change is small enough,
1222      *	the characters that belong there are written to move the
1223      *	cursor over.
1224      *
1225      *	Invariants:
1226      *	    lastcol is the column where the cursor currently is sitting
1227      *		(always one beyond the end of the last mismatch).
1228      */
1229     do		/* yes, a do...while */
1230     {
1231 	if ((ch = *new++) != *old)
1232 	{
1233 	    /* new character is different from old	  */
1234 	    /* make sure the cursor is on top of this character */
1235 	    diff = newcol - lastcol;
1236 	    if (diff > 0)
1237 	    {
1238 		/* some motion is required--figure out which is shorter */
1239 		if (diff < 6 && cursor_on_line)
1240 		{
1241 		    /* overwrite old stuff--get it out of the old buffer */
1242 		    printf("%.*s", diff, &current[lastcol-start]);
1243 		}
1244 		else
1245 		{
1246 		    /* use cursor addressing */
1247 		    Move_to(newcol, line);
1248 		    cursor_on_line = true;
1249 		}
1250 		/* remember where the cursor is */
1251 		lastcol = newcol + 1;
1252 	    }
1253 	    else
1254 	    {
1255 		/* already there, update position */
1256 		lastcol++;
1257 	    }
1258 
1259 	    /* write what we need to */
1260 	    if (ch == '\0')
1261 	    {
1262 		/* at the end--terminate with a clear-to-end-of-line */
1263 		(void) clear_eol(strlen(old));
1264 	    }
1265 	    else
1266 	    {
1267 		/* write the new character */
1268 		putchar(ch);
1269 	    }
1270 	    /* put the new character in the screen buffer */
1271 	    *old = ch;
1272 	}
1273 
1274 	/* update working column and screen buffer pointer */
1275 	newcol++;
1276 	old++;
1277 
1278     } while (ch != '\0');
1279 
1280     /* zero out the rest of the line buffer -- MUST BE DONE! */
1281     diff = screen_width - newcol;
1282     if (diff > 0)
1283     {
1284 	memset(old, 0, diff);
1285     }
1286 
1287     /* remember where the current line is */
1288     if (cursor_on_line)
1289     {
1290 	lastline = line;
1291     }
1292 }
1293 
1294 void
1295 i_uptime(struct timeval *bt, time_t *tod)
1296 {
1297     time_t uptime;
1298     int days, hrs, mins, secs;
1299 
1300     if (bt->tv_sec != -1) {
1301 	uptime = *tod - bt->tv_sec;
1302 	days = uptime / 86400;
1303 	uptime %= 86400;
1304 	hrs = uptime / 3600;
1305 	uptime %= 3600;
1306 	mins = uptime / 60;
1307 	secs = uptime % 60;
1308 
1309 	/*
1310 	 *  Display the uptime.
1311 	 */
1312 
1313 	if (smart_terminal)
1314 	{
1315 	    Move_to((screen_width - 24) - (days > 9 ? 1 : 0), 0);
1316 	}
1317 	else
1318 	{
1319 	    fputs(" ", stdout);
1320 	}
1321 	printf(" up %d+%02d:%02d:%02d", days, hrs, mins, secs);
1322     }
1323 }
1324 
1325 void
1326 i_battery(int nbat, int batt)
1327 {
1328 
1329 	if (nbat > 0) {
1330 		printf("; battery: %d%%", batt);
1331 	}
1332 }
1333 
1334 #define SETUPBUFFER_MIN_SCREENWIDTH 80
1335 #define SETUPBUFFER_REQUIRED_ADDBUFSIZ 2
1336 
1337 static char *
1338 setup_buffer(char *buffer, int addlen)
1339 {
1340     size_t len, old_len;
1341     char *new_buffer;
1342 
1343     setup_buffer_bufsiz = screen_width;
1344     if (setup_buffer_bufsiz < SETUPBUFFER_MIN_SCREENWIDTH)
1345     {
1346 	setup_buffer_bufsiz = SETUPBUFFER_MIN_SCREENWIDTH;
1347     }
1348 
1349     len = setup_buffer_bufsiz + addlen + SETUPBUFFER_REQUIRED_ADDBUFSIZ;
1350     new_buffer = calloc(len, sizeof(char));
1351     if (new_buffer == NULL)
1352     {
1353 	errx(4, "can't allocate sufficient memory");
1354     }
1355     if (buffer != NULL)
1356     {
1357 	old_len = strlen(buffer);
1358 	memcpy(new_buffer, buffer, old_len < len - 1 ? old_len : len - 1);
1359 	free(buffer);
1360     }
1361 
1362     return new_buffer;
1363 }
1364