summaryrefslogtreecommitdiffstats
path: root/contrib/nvi/vi/vs_refresh.c
blob: f69d3820db7f566962d4bc57d20017cbb49a3ab5 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
/*-
 * Copyright (c) 1992, 1993, 1994
 *	The Regents of the University of California.  All rights reserved.
 * Copyright (c) 1992, 1993, 1994, 1995, 1996
 *	Keith Bostic.  All rights reserved.
 *
 * See the LICENSE file for redistribution information.
 */

#include "config.h"

#ifndef lint
#if 0
static const char sccsid[] = "@(#)vs_refresh.c	10.44 (Berkeley) 10/13/96";
#endif
static const char rcsid[] =
  "$FreeBSD$";
#endif /* not lint */

#include <sys/types.h>
#include <sys/queue.h>
#include <sys/time.h>

#include <bitstring.h>
#include <ctype.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "../common/common.h"
#include "vi.h"

#define	UPDATE_CURSOR	0x01			/* Update the cursor. */
#define	UPDATE_SCREEN	0x02			/* Flush to screen. */

static void	vs_modeline __P((SCR *));
static int	vs_paint __P((SCR *, u_int));

/*
 * v_repaint --
 *	Repaint selected lines from the screen.
 *
 * PUBLIC: int vs_repaint __P((SCR *, EVENT *));
 */
int
vs_repaint(sp, evp)
	SCR *sp;
	EVENT *evp;
{
	SMAP *smp;

	for (; evp->e_flno <= evp->e_tlno; ++evp->e_flno) {
		smp = HMAP + evp->e_flno - 1;
		SMAP_FLUSH(smp);
		if (vs_line(sp, smp, NULL, NULL))
			return (1);
	}
	return (0);
}

/*
 * vs_refresh --
 *	Refresh all screens.
 *
 * PUBLIC: int vs_refresh __P((SCR *, int));
 */
int
vs_refresh(sp, forcepaint)
	SCR *sp;
	int forcepaint;
{
	GS *gp;
	SCR *tsp;
	int need_refresh;
	u_int priv_paint, pub_paint;

	gp = sp->gp;

	/*
	 * 1: Refresh the screen.
	 *
	 * If SC_SCR_REDRAW is set in the current screen, repaint everything
	 * that we can find, including status lines.
	 */
	if (F_ISSET(sp, SC_SCR_REDRAW))
		for (tsp = gp->dq.cqh_first;
		    tsp != (void *)&gp->dq; tsp = tsp->q.cqe_next)
			if (tsp != sp)
				F_SET(tsp, SC_SCR_REDRAW | SC_STATUS);

	/*
	 * 2: Related or dirtied screens, or screens with messages.
	 *
	 * If related screens share a view into a file, they may have been
	 * modified as well.  Refresh any screens that aren't exiting that
	 * have paint or dirty bits set.  Always update their screens, we
	 * are not likely to get another chance.  Finally, if we refresh any
	 * screens other than the current one, the cursor will be trashed.
	 */
	pub_paint = SC_SCR_REFORMAT | SC_SCR_REDRAW;
	priv_paint = VIP_CUR_INVALID | VIP_N_REFRESH;
	if (O_ISSET(sp, O_NUMBER))
		priv_paint |= VIP_N_RENUMBER;
	for (tsp = gp->dq.cqh_first;
	    tsp != (void *)&gp->dq; tsp = tsp->q.cqe_next)
		if (tsp != sp && !F_ISSET(tsp, SC_EXIT | SC_EXIT_FORCE) &&
		    (F_ISSET(tsp, pub_paint) ||
		    F_ISSET(VIP(tsp), priv_paint))) {
			(void)vs_paint(tsp,
			    (F_ISSET(VIP(tsp), VIP_CUR_INVALID) ?
			    UPDATE_CURSOR : 0) | UPDATE_SCREEN);
			F_SET(VIP(sp), VIP_CUR_INVALID);
		}

	/*
	 * 3: Refresh the current screen.
	 *
	 * Always refresh the current screen, it may be a cursor movement.
	 * Also, always do it last -- that way, SC_SCR_REDRAW can be set
	 * in the current screen only, and the screen won't flash.
	 */
	if (vs_paint(sp, UPDATE_CURSOR | (!forcepaint &&
	    F_ISSET(sp, SC_SCR_VI) && KEYS_WAITING(sp) ? 0 : UPDATE_SCREEN)))
		return (1);

	/*
	 * 4: Paint any missing status lines.
	 *
	 * XXX
	 * This is fairly evil.  Status lines are written using the vi message
	 * mechanism, since we have no idea how long they are.  Since we may be
	 * painting screens other than the current one, we don't want to make
	 * the user wait.  We depend heavily on there not being any other lines
	 * currently waiting to be displayed and the message truncation code in
	 * the msgq_status routine working.
	 *
	 * And, finally, if we updated any status lines, make sure the cursor
	 * gets back to where it belongs.
	 */
	for (need_refresh = 0, tsp = gp->dq.cqh_first;
	    tsp != (void *)&gp->dq; tsp = tsp->q.cqe_next)
		if (F_ISSET(tsp, SC_STATUS)) {
			need_refresh = 1;
			vs_resolve(tsp, sp, 0);
		}
	if (need_refresh)
		(void)gp->scr_refresh(sp, 0);

	/*
	 * A side-effect of refreshing the screen is that it's now ready
	 * for everything else, i.e. messages.
	 */
	F_SET(sp, SC_SCR_VI);
	return (0);
}

/*
 * vs_paint --
 *	This is the guts of the vi curses screen code.  The idea is that
 *	the SCR structure passed in contains the new coordinates of the
 *	screen.  What makes this hard is that we don't know how big
 *	characters are, doing input can put the cursor in illegal places,
 *	and we're frantically trying to avoid repainting unless it's
 *	absolutely necessary.  If you change this code, you'd better know
 *	what you're doing.  It's subtle and quick to anger.
 */
static int
vs_paint(sp, flags)
	SCR *sp;
	u_int flags;
{
	GS *gp;
	SMAP *smp, tmp;
	VI_PRIVATE *vip;
	recno_t lastline, lcnt;
	size_t cwtotal, cnt, len, notused, off, y;
	int ch, didpaint, isempty, leftright_warp;
	char *p;

#define	 LNO	sp->lno			/* Current file line. */
#define	OLNO	vip->olno		/* Remembered file line. */
#define	 CNO	sp->cno			/* Current file column. */
#define	OCNO	vip->ocno		/* Remembered file column. */
#define	SCNO	vip->sc_col		/* Current screen column. */

	gp = sp->gp;
	vip = VIP(sp);
	didpaint = leftright_warp = 0;

	/*
	 * 5: Reformat the lines.
	 *
	 * If the lines themselves have changed (:set list, for example),
	 * fill in the map from scratch.  Adjust the screen that's being
	 * displayed if the leftright flag is set.
	 */
	if (F_ISSET(sp, SC_SCR_REFORMAT)) {
		/* Invalidate the line size cache. */
		VI_SCR_CFLUSH(vip);

		/* Toss vs_line() cached information. */
		if (F_ISSET(sp, SC_SCR_TOP)) {
			if (vs_sm_fill(sp, LNO, P_TOP))
				return (1);
		}
		else if (F_ISSET(sp, SC_SCR_CENTER)) {
			if (vs_sm_fill(sp, LNO, P_MIDDLE))
				return (1);
		} else
			if (vs_sm_fill(sp, OOBLNO, P_TOP))
				return (1);
		F_SET(sp, SC_SCR_REDRAW);
	}

	/*
	 * 6: Line movement.
	 *
	 * Line changes can cause the top line to change as well.  As
	 * before, if the movement is large, the screen is repainted.
	 *
	 * 6a: Small screens.
	 *
	 * Users can use the window, w300, w1200 and w9600 options to make
	 * the screen artificially small.  The behavior of these options
	 * in the historic vi wasn't all that consistent, and, in fact, it
	 * was never documented how various screen movements affected the
	 * screen size.  Generally, one of three things would happen:
	 *	1: The screen would expand in size, showing the line
	 *	2: The screen would scroll, showing the line
	 *	3: The screen would compress to its smallest size and
	 *		repaint.
	 * In general, scrolling didn't cause compression (200^D was handled
	 * the same as ^D), movement to a specific line would (:N where N
	 * was 1 line below the screen caused a screen compress), and cursor
	 * movement would scroll if it was 11 lines or less, and compress if
	 * it was more than 11 lines.  (And, no, I have no idea where the 11
	 * comes from.)
	 *
	 * What we do is try and figure out if the line is less than half of
	 * a full screen away.  If it is, we expand the screen if there's
	 * room, and then scroll as necessary.  The alternative is to compress
	 * and repaint.
	 *
	 * !!!
	 * This code is a special case from beginning to end.  Unfortunately,
	 * home modems are still slow enough that it's worth having.
	 *
	 * XXX
	 * If the line a really long one, i.e. part of the line is on the
	 * screen but the column offset is not, we'll end up in the adjust
	 * code, when we should probably have compressed the screen.
	 */
	if (IS_SMALL(sp))
		if (LNO < HMAP->lno) {
			lcnt = vs_sm_nlines(sp, HMAP, LNO, sp->t_maxrows);
			if (lcnt <= HALFSCREEN(sp))
				for (; lcnt && sp->t_rows != sp->t_maxrows;
				     --lcnt, ++sp->t_rows) {
					++TMAP;
					if (vs_sm_1down(sp))
						return (1);
				}
			else
				goto small_fill;
		} else if (LNO > TMAP->lno) {
			lcnt = vs_sm_nlines(sp, TMAP, LNO, sp->t_maxrows);
			if (lcnt <= HALFSCREEN(sp))
				for (; lcnt && sp->t_rows != sp->t_maxrows;
				     --lcnt, ++sp->t_rows) {
					if (vs_sm_next(sp, TMAP, TMAP + 1))
						return (1);
					++TMAP;
					if (vs_line(sp, TMAP, NULL, NULL))
						return (1);
				}
			else {
small_fill:			(void)gp->scr_move(sp, LASTLINE(sp), 0);
				(void)gp->scr_clrtoeol(sp);
				for (; sp->t_rows > sp->t_minrows;
				    --sp->t_rows, --TMAP) {
					(void)gp->scr_move(sp, TMAP - HMAP, 0);
					(void)gp->scr_clrtoeol(sp);
				}
				if (vs_sm_fill(sp, LNO, P_FILL))
					return (1);
				F_SET(sp, SC_SCR_REDRAW);
				goto adjust;
			}
		}

	/*
	 * 6b: Line down, or current screen.
	 */
	if (LNO >= HMAP->lno) {
		/* Current screen. */
		if (LNO <= TMAP->lno)
			goto adjust;
		if (F_ISSET(sp, SC_SCR_TOP))
			goto top;
		if (F_ISSET(sp, SC_SCR_CENTER))
			goto middle;

		/*
		 * If less than half a screen above the line, scroll down
		 * until the line is on the screen.
		 */
		lcnt = vs_sm_nlines(sp, TMAP, LNO, HALFTEXT(sp));
		if (lcnt < HALFTEXT(sp)) {
			while (lcnt--)
				if (vs_sm_1up(sp))
					return (1);
			goto adjust;
		}
		goto bottom;
	}

	/*
	 * 6c: If not on the current screen, may request center or top.
	 */
	if (F_ISSET(sp, SC_SCR_TOP))
		goto top;
	if (F_ISSET(sp, SC_SCR_CENTER))
		goto middle;

	/*
	 * 6d: Line up.
	 */
	lcnt = vs_sm_nlines(sp, HMAP, LNO, HALFTEXT(sp));
	if (lcnt < HALFTEXT(sp)) {
		/*
		 * If less than half a screen below the line, scroll up until
		 * the line is the first line on the screen.  Special check so
		 * that if the screen has been emptied, we refill it.
		 */
		if (db_exist(sp, HMAP->lno)) {
			while (lcnt--)
				if (vs_sm_1down(sp))
					return (1);
			goto adjust;
		}

		/*
		 * If less than a half screen from the bottom of the file,
		 * put the last line of the file on the bottom of the screen.
		 */
bottom:		if (db_last(sp, &lastline))
			return (1);
		tmp.lno = LNO;
		tmp.coff = HMAP->coff;
		tmp.soff = 1;
		lcnt = vs_sm_nlines(sp, &tmp, lastline, sp->t_rows);
		if (lcnt < HALFTEXT(sp)) {
			if (vs_sm_fill(sp, lastline, P_BOTTOM))
				return (1);
			F_SET(sp, SC_SCR_REDRAW);
			goto adjust;
		}
		/* It's not close, just put the line in the middle. */
		goto middle;
	}

	/*
	 * If less than half a screen from the top of the file, put the first
	 * line of the file at the top of the screen.  Otherwise, put the line
	 * in the middle of the screen.
	 */
	tmp.lno = 1;
	tmp.coff = HMAP->coff;
	tmp.soff = 1;
	lcnt = vs_sm_nlines(sp, &tmp, LNO, HALFTEXT(sp));
	if (lcnt < HALFTEXT(sp)) {
		if (vs_sm_fill(sp, 1, P_TOP))
			return (1);
	} else
middle:		if (vs_sm_fill(sp, LNO, P_MIDDLE))
			return (1);
	if (0) {
top:		if (vs_sm_fill(sp, LNO, P_TOP))
			return (1);
	}
	F_SET(sp, SC_SCR_REDRAW);

	/*
	 * At this point we know part of the line is on the screen.  Since
	 * scrolling is done using logical lines, not physical, all of the
	 * line may not be on the screen.  While that's not necessarily bad,
	 * if the part the cursor is on isn't there, we're going to lose.
	 * This can be tricky; if the line covers the entire screen, lno
	 * may be the same as both ends of the map, that's why we test BOTH
	 * the top and the bottom of the map.  This isn't a problem for
	 * left-right scrolling, the cursor movement code handles the problem.
	 *
	 * There's a performance issue here if editing *really* long lines.
	 * This gets to the right spot by scrolling, and, in a binary, by
	 * scrolling hundreds of lines.  If the adjustment looks like it's
	 * going to be a serious problem, refill the screen and repaint.
	 */
adjust:	if (!O_ISSET(sp, O_LEFTRIGHT) &&
	    (LNO == HMAP->lno || LNO == TMAP->lno)) {
		cnt = vs_screens(sp, LNO, &CNO);
		if (LNO == HMAP->lno && cnt < HMAP->soff)
			if ((HMAP->soff - cnt) > HALFTEXT(sp)) {
				HMAP->soff = cnt;
				vs_sm_fill(sp, OOBLNO, P_TOP);
				F_SET(sp, SC_SCR_REDRAW);
			} else
				while (cnt < HMAP->soff)
					if (vs_sm_1down(sp))
						return (1);
		if (LNO == TMAP->lno && cnt > TMAP->soff)
			if ((cnt - TMAP->soff) > HALFTEXT(sp)) {
				TMAP->soff = cnt;
				vs_sm_fill(sp, OOBLNO, P_BOTTOM);
				F_SET(sp, SC_SCR_REDRAW);
			} else
				while (cnt > TMAP->soff)
					if (vs_sm_1up(sp))
						return (1);
	}

	/*
	 * If the screen needs to be repainted, skip cursor optimization.
	 * However, in the code above we skipped leftright scrolling on
	 * the grounds that the cursor code would handle it.  Make sure
	 * the right screen is up.
	 */
	if (F_ISSET(sp, SC_SCR_REDRAW)) {
		if (O_ISSET(sp, O_LEFTRIGHT))
			goto slow;
		goto paint;
	}

	/*
	 * 7: Cursor movements (current screen only).
	 */
	if (!LF_ISSET(UPDATE_CURSOR))
		goto number;

	/*
	 * Decide cursor position.  If the line has changed, the cursor has
	 * moved over a tab, or don't know where the cursor was, reparse the
	 * line.  Otherwise, we've just moved over fixed-width characters,
	 * and can calculate the left/right scrolling and cursor movement
	 * without reparsing the line.  Note that we don't know which (if any)
	 * of the characters between the old and new cursor positions changed.
	 *
	 * XXX
	 * With some work, it should be possible to handle tabs quickly, at
	 * least in obvious situations, like moving right and encountering
	 * a tab, without reparsing the whole line.
	 *
	 * If the line we're working with has changed, reread it..
	 */
	if (F_ISSET(vip, VIP_CUR_INVALID) || LNO != OLNO)
		goto slow;

	/* Otherwise, if nothing's changed, ignore the cursor. */
	if (CNO == OCNO)
		goto fast;

	/*
	 * Get the current line.  If this fails, we either have an empty
	 * file and can just repaint, or there's a real problem.  This
	 * isn't a performance issue because there aren't any ways to get
	 * here repeatedly.
	 */
	if (db_eget(sp, LNO, &p, &len, &isempty)) {
		if (isempty)
			goto slow;
		return (1);
	}

#ifdef DEBUG
	/* Sanity checking. */
	if (CNO >= len && len != 0) {
		msgq(sp, M_ERR, "Error: %s/%d: cno (%u) >= len (%u)",
		     tail(__FILE__), __LINE__, CNO, len);
		return (1);
	}
#endif
	/*
	 * The basic scheme here is to look at the characters in between
	 * the old and new positions and decide how big they are on the
	 * screen, and therefore, how many screen positions to move.
	 */
	if (CNO < OCNO) {
		/*
		 * 7a: Cursor moved left.
		 *
		 * Point to the old character.  The old cursor position can
		 * be past EOL if, for example, we just deleted the rest of
		 * the line.  In this case, since we don't know the width of
		 * the characters we traversed, we have to do it slowly.
		 */
		p += OCNO;
		cnt = (OCNO - CNO) + 1;
		if (OCNO >= len)
			goto slow;

		/*
		 * Quick sanity check -- it's hard to figure out exactly when
		 * we cross a screen boundary as we do in the cursor right
		 * movement.  If cnt is so large that we're going to cross the
		 * boundary no matter what, stop now.
		 */
		if (SCNO + 1 + MAX_CHARACTER_COLUMNS < cnt)
			goto slow;

		/*
		 * Count up the widths of the characters.  If it's a tab
		 * character, go do it the the slow way.
		 */
		for (cwtotal = 0; cnt--; cwtotal += KEY_LEN(sp, ch))
			if ((ch = *(u_char *)p--) == '\t')
				goto slow;

		/*
		 * Decrement the screen cursor by the total width of the
		 * characters minus 1.
		 */
		cwtotal -= 1;

		/*
		 * If we're moving left, and there's a wide character in the
		 * current position, go to the end of the character.
		 */
		if (KEY_LEN(sp, ch) > 1)
			cwtotal -= KEY_LEN(sp, ch) - 1;

		/*
		 * If the new column moved us off of the current logical line,
		 * calculate a new one.  If doing leftright scrolling, we've
		 * moved off of the current screen, as well.
		 */
		if (SCNO < cwtotal)
			goto slow;
		SCNO -= cwtotal;
	} else {
		/*
		 * 7b: Cursor moved right.
		 *
		 * Point to the first character to the right.
		 */
		p += OCNO + 1;
		cnt = CNO - OCNO;

		/*
		 * Count up the widths of the characters.  If it's a tab
		 * character, go do it the the slow way.  If we cross a
		 * screen boundary, we can quit.
		 */
		for (cwtotal = SCNO; cnt--;) {
			if ((ch = *(u_char *)p++) == '\t')
				goto slow;
			if ((cwtotal += KEY_LEN(sp, ch)) >= SCREEN_COLS(sp))
				break;
		}

		/*
		 * Increment the screen cursor by the total width of the
		 * characters.
		 */
		SCNO = cwtotal;

		/* See screen change comment in section 6a. */
		if (SCNO >= SCREEN_COLS(sp))
			goto slow;
	}

	/*
	 * 7c: Fast cursor update.
	 *
	 * We have the current column, retrieve the current row.
	 */
fast:	(void)gp->scr_cursor(sp, &y, &notused);
	goto done_cursor;

	/*
	 * 7d: Slow cursor update.
	 *
	 * Walk through the map and find the current line.
	 */
slow:	for (smp = HMAP; smp->lno != LNO; ++smp);

	/*
	 * 7e: Leftright scrolling adjustment.
	 *
	 * If doing left-right scrolling and the cursor movement has changed
	 * the displayed screen, scroll the screen left or right, unless we're
	 * updating the info line in which case we just scroll that one line.
	 * We adjust the offset up or down until we have a window that covers
	 * the current column, making sure that we adjust differently for the
	 * first screen as compared to subsequent ones.
	 */
	if (O_ISSET(sp, O_LEFTRIGHT)) {
		/*
		 * Get the screen column for this character, and correct
		 * for the number option offset.
		 */
		cnt = vs_columns(sp, NULL, LNO, &CNO, NULL);
		if (O_ISSET(sp, O_NUMBER) && cnt >= O_NUMBER_LENGTH)
			cnt -= O_NUMBER_LENGTH;

		/* Adjust the window towards the beginning of the line. */
		off = smp->coff;
		if (off >= cnt) {
			do {
				if (off >= O_VAL(sp, O_SIDESCROLL))
					off -= O_VAL(sp, O_SIDESCROLL);
				else {
					off = 0;
					break;
				}
			} while (off >= cnt);
			goto shifted;
		}

		/* Adjust the window towards the end of the line. */
		if (off == 0 && off + SCREEN_COLS(sp) < cnt ||
		    off != 0 && off + sp->cols < cnt) {
			do {
				off += O_VAL(sp, O_SIDESCROLL);
			} while (off + sp->cols < cnt);

shifted:		/* Fill in screen map with the new offset. */
			if (F_ISSET(sp, SC_TINPUT_INFO))
				smp->coff = off;
			else {
				for (smp = HMAP; smp <= TMAP; ++smp)
					smp->coff = off;
				leftright_warp = 1;
			}
			goto paint;
		}

		/*
		 * We may have jumped here to adjust a leftright screen because
		 * redraw was set.  If so, we have to paint the entire screen.
		 */
		if (F_ISSET(sp, SC_SCR_REDRAW))
			goto paint;
	}

	/*
	 * Update the screen lines for this particular file line until we
	 * have a new screen cursor position.
	 */
	for (y = -1,
	    vip->sc_smap = NULL; smp <= TMAP && smp->lno == LNO; ++smp) {
		if (vs_line(sp, smp, &y, &SCNO))
			return (1);
		if (y != -1) {
			vip->sc_smap = smp;
			break;
		}
	}
	goto done_cursor;

	/*
	 * 8: Repaint the entire screen.
	 *
	 * Lost big, do what you have to do.  We flush the cache, since
	 * SC_SCR_REDRAW gets set when the screen isn't worth fixing, and
	 * it's simpler to repaint.  So, don't trust anything that we
	 * think we know about it.
	 */
paint:	for (smp = HMAP; smp <= TMAP; ++smp)
		SMAP_FLUSH(smp);
	for (y = -1, vip->sc_smap = NULL, smp = HMAP; smp <= TMAP; ++smp) {
		if (vs_line(sp, smp, &y, &SCNO))
			return (1);
		if (y != -1 && vip->sc_smap == NULL)
			vip->sc_smap = smp;
	}
	/*
	 * If it's a small screen and we're redrawing, clear the unused lines,
	 * ex may have overwritten them.
	 */
	if (F_ISSET(sp, SC_SCR_REDRAW) && IS_SMALL(sp))
		for (cnt = sp->t_rows; cnt <= sp->t_maxrows; ++cnt) {
			(void)gp->scr_move(sp, cnt, 0);
			(void)gp->scr_clrtoeol(sp);
		}

	didpaint = 1;

done_cursor:
	/*
	 * Sanity checking.  When the repainting code messes up, the usual
	 * result is we don't repaint the cursor and so sc_smap will be
	 * NULL.  If we're debugging, die, otherwise restart from scratch.
	 */
#ifdef DEBUG
	if (vip->sc_smap == NULL)
		abort();
#else
	if (vip->sc_smap == NULL) {
		F_SET(sp, SC_SCR_REFORMAT);
		return (vs_paint(sp, flags));
	}
#endif

	/*
	 * 9: Set the remembered cursor values.
	 */
	OCNO = CNO;
	OLNO = LNO;

	/*
	 * 10: Repaint the line numbers.
	 *
	 * If O_NUMBER is set and the VIP_N_RENUMBER bit is set, and we
	 * didn't repaint the screen, repaint all of the line numbers,
	 * they've changed.
	 */
number:	if (O_ISSET(sp, O_NUMBER) &&
	    F_ISSET(vip, VIP_N_RENUMBER) && !didpaint && vs_number(sp))
		return (1);

	/*
	 * 11: Update the mode line, position the cursor, and flush changes.
	 *
	 * If we warped the screen, we have to refresh everything.
	 */
	if (leftright_warp)
		LF_SET(UPDATE_CURSOR | UPDATE_SCREEN);

	if (LF_ISSET(UPDATE_SCREEN) && !IS_ONELINE(sp) &&
	    !F_ISSET(vip, VIP_S_MODELINE) && !F_ISSET(sp, SC_TINPUT_INFO))
		vs_modeline(sp);

	if (LF_ISSET(UPDATE_CURSOR)) {
		(void)gp->scr_move(sp, y, SCNO);

		/*
		 * XXX
		 * If the screen shifted, we recalculate the "most favorite"
		 * cursor position.  Vi won't know that we've warped the
		 * screen, so it's going to have a wrong idea about where the
		 * cursor should be.  This is vi's problem, and fixing it here
		 * is a gross layering violation.
		 */
		if (leftright_warp)
			(void)vs_column(sp, &sp->rcm);
	}

	if (LF_ISSET(UPDATE_SCREEN))
		(void)gp->scr_refresh(sp, F_ISSET(vip, VIP_N_EX_PAINT));

	/* 12: Clear the flags that are handled by this routine. */
	F_CLR(sp, SC_SCR_CENTER | SC_SCR_REDRAW | SC_SCR_REFORMAT | SC_SCR_TOP);
	F_CLR(vip, VIP_CUR_INVALID |
	    VIP_N_EX_PAINT | VIP_N_REFRESH | VIP_N_RENUMBER | VIP_S_MODELINE);

	return (0);

#undef	 LNO
#undef	OLNO
#undef	 CNO
#undef	OCNO
#undef	SCNO
}

/*
 * vs_modeline --
 *	Update the mode line.
 */
static void
vs_modeline(sp)
	SCR *sp;
{
	static char * const modes[] = {
		"215|Append",			/* SM_APPEND */
		"216|Change",			/* SM_CHANGE */
		"217|Command",			/* SM_COMMAND */
		"218|Insert",			/* SM_INSERT */
		"219|Replace",			/* SM_REPLACE */
	};
	GS *gp;
	size_t cols, curcol, curlen, endpoint, len, midpoint;
	const char *t;
	int ellipsis;
	char *p, buf[20];

	gp = sp->gp;

	/*
	 * We put down the file name, the ruler, the mode and the dirty flag.
	 * If there's not enough room, there's not enough room, we don't play
	 * any special games.  We try to put the ruler in the middle and the
	 * mode and dirty flag at the end.
	 *
	 * !!!
	 * Leave the last character blank, in case it's a really dumb terminal
	 * with hardware scroll.  Second, don't paint the last character in the
	 * screen, SunOS 4.1.1 and Ultrix 4.2 curses won't let you.
	 *
	 * Move to the last line on the screen.
	 */
	(void)gp->scr_move(sp, LASTLINE(sp), 0);

	/* If more than one screen in the display, show the file name. */
	curlen = 0;
	if (IS_SPLIT(sp)) {
		for (p = sp->frp->name; *p != '\0'; ++p);
		for (ellipsis = 0, cols = sp->cols / 2; --p > sp->frp->name;) {
			if (*p == '/') {
				++p;
				break;
			}
			if ((curlen += KEY_LEN(sp, *p)) > cols) {
				ellipsis = 3;
				curlen +=
				    KEY_LEN(sp, '.') * 3 + KEY_LEN(sp, ' ');
				while (curlen > cols) {
					++p;
					curlen -= KEY_LEN(sp, *p);
				}
				break;
			}
		}
		if (ellipsis) {
			while (ellipsis--)
				(void)gp->scr_addstr(sp,
				    KEY_NAME(sp, '.'), KEY_LEN(sp, '.'));
			(void)gp->scr_addstr(sp,
			    KEY_NAME(sp, ' '), KEY_LEN(sp, ' '));
		}
		for (; *p != '\0'; ++p)
			(void)gp->scr_addstr(sp,
			    KEY_NAME(sp, *p), KEY_LEN(sp, *p));
	}

	/* Clear the rest of the line. */
	(void)gp->scr_clrtoeol(sp);

	/*
	 * Display the ruler.  If we're not at the midpoint yet, move there.
	 * Otherwise, add in two extra spaces.
	 *
	 * Adjust the current column for the fact that the editor uses it as
	 * a zero-based number.
	 *
	 * XXX
	 * Assume that numbers, commas, and spaces only take up a single
	 * column on the screen.
	 */
	cols = sp->cols - 1;
	if (O_ISSET(sp, O_RULER)) {
		vs_column(sp, &curcol);
		len = snprintf(buf, sizeof(buf), "%lu,%lu",
		    (u_long)sp->lno, (u_long)(curcol + 1));

		midpoint = (cols - ((len + 1) / 2)) / 2;
		if (curlen < midpoint) {
			(void)gp->scr_move(sp, LASTLINE(sp), midpoint);
			curlen += len;
		} else if (curlen + 2 + len < cols) {
			(void)gp->scr_addstr(sp, "  ", 2);
			curlen += 2 + len;
		}
		(void)gp->scr_addstr(sp, buf, len);
	}

	/*
	 * Display the mode and the modified flag, as close to the end of the
	 * line as possible, but guaranteeing at least two spaces between the
	 * ruler and the modified flag.
	 */
#define	MODESIZE	9
	endpoint = cols;
	if (O_ISSET(sp, O_SHOWMODE)) {
		if (F_ISSET(sp->ep, F_MODIFIED))
			--endpoint;
		t = msg_cat(sp, modes[sp->showmode], &len);
		endpoint -= len;
	}

	if (endpoint > curlen + 2) {
		(void)gp->scr_move(sp, LASTLINE(sp), endpoint);
		if (O_ISSET(sp, O_SHOWMODE)) {
			if (F_ISSET(sp->ep, F_MODIFIED))
				(void)gp->scr_addstr(sp,
				    KEY_NAME(sp, '*'), KEY_LEN(sp, '*'));
			(void)gp->scr_addstr(sp, t, len);
		}
	}
}
OpenPOWER on IntegriCloud