xref: /netbsd-src/lib/libcurses/refresh.c (revision 181254a7b1bdde6873432bffef2d2decc4b5c22f)
1 /*	$NetBSD: refresh.c,v 1.112 2020/02/24 12:20:29 rin Exp $	*/
2 
3 /*
4  * Copyright (c) 1981, 1993, 1994
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 #ifndef lint
34 #if 0
35 static char sccsid[] = "@(#)refresh.c	8.7 (Berkeley) 8/13/94";
36 #else
37 __RCSID("$NetBSD: refresh.c,v 1.112 2020/02/24 12:20:29 rin Exp $");
38 #endif
39 #endif				/* not lint */
40 
41 #include <poll.h>
42 #include <stdlib.h>
43 #include <string.h>
44 
45 #include "curses.h"
46 #include "curses_private.h"
47 
48 static void	domvcur(WINDOW *, int, int, int, int);
49 static void	putattr(__LDATA *);
50 static void	putattr_out(__LDATA *);
51 static int	putch(__LDATA *, __LDATA *, int, int);
52 static int	putchbr(__LDATA *, __LDATA *, __LDATA *, int, int);
53 static int	makech(int);
54 static void	quickch(void);
55 static void	scrolln(int, int, int, int, int);
56 
57 static int	_wnoutrefresh(WINDOW *, int, int, int, int, int, int);
58 
59 #ifdef HAVE_WCHAR
60 static int celleq(__LDATA *, __LDATA *);
61 static int lineeq(__LDATA *, __LDATA *, size_t);
62 #else  /* !HAVE_WCHAR */
63 static inline int
64 celleq(__LDATA *x, __LDATA *y)
65 {
66 	return memcmp(x, y, sizeof(__LDATA)) == 0;
67 }
68 
69 static int
70 lineeq(__LDATA *xl, __LDATA *yl, size_t len)
71 {
72 	return memcmp(xl, yl, len * __LDATASIZE) == 0;
73 }
74 #endif /* HAVE_WCHAR */
75 
76 #define	CHECK_INTERVAL		5 /* Change N lines before checking typeahead */
77 
78 #ifndef _CURSES_USE_MACROS
79 
80 /*
81  * refresh --
82  *	Make the current screen look like "stdscr" over the area covered by
83  *	stdscr.
84  */
85 int
86 refresh(void)
87 {
88 
89 	return wrefresh(stdscr);
90 }
91 
92 #endif
93 
94 /*
95  * wnoutrefresh --
96  *	Add the contents of "win" to the virtual window.
97  */
98 int
99 wnoutrefresh(WINDOW *win)
100 {
101 
102 #ifdef DEBUG
103 	__CTRACE(__CTRACE_REFRESH, "wnoutrefresh: win %p, begy %d, begx %d, maxy %d, maxx %d\n", win, win->begy, win->begx, win->maxy, win->maxx);
104 #endif
105 
106 	return _wnoutrefresh(win, 0, 0, win->begy, win->begx,
107 	    win->maxy, win->maxx);
108 }
109 
110 /*
111  * pnoutrefresh --
112  *	Add the contents of "pad" to the virtual window.
113  */
114 int
115 pnoutrefresh(WINDOW *pad, int pbegy, int pbegx, int sbegy, int sbegx,
116 	     int smaxy, int smaxx)
117 {
118 	int pmaxy, pmaxx;
119 
120 #ifdef DEBUG
121 	__CTRACE(__CTRACE_REFRESH, "pnoutrefresh: pad %p, flags 0x%08x\n",
122 	    pad, pad->flags);
123 	__CTRACE(__CTRACE_REFRESH,
124 	    "pnoutrefresh: (%d, %d), (%d, %d), (%d, %d)\n",
125 	    pbegy, pbegx, sbegy, sbegx, smaxy, smaxx);
126 #endif
127 
128 	/* SUS says if these are negative, they should be treated as zero */
129 	if (pbegy < 0)
130 		pbegy = 0;
131 	if (pbegx < 0)
132 		pbegx = 0;
133 	if (sbegy < 0)
134 		sbegy = 0;
135 	if (sbegx < 0)
136 		sbegx = 0;
137 
138 	/* Calculate rectangle on pad - used by _wnoutrefresh */
139 	pmaxy = pbegy + smaxy - sbegy + 1;
140 	pmaxx = pbegx + smaxx - sbegx + 1;
141 
142 	/* Check rectangle fits in pad */
143 	if (pmaxy > pad->maxy - pad->begy)
144 		pmaxy = pad->maxy - pad->begy;
145 	if (pmaxx > pad->maxx - pad->begx)
146 		pmaxx = pad->maxx - pad->begx;
147 
148 	if (smaxy - sbegy < 0 || smaxx - sbegx < 0 )
149 		return ERR;
150 
151 	return _wnoutrefresh(pad,
152 	    pad->begy + pbegy, pad->begx + pbegx, pad->begy + sbegy,
153 	    pad->begx + sbegx, pmaxy, pmaxx);
154 }
155 
156 /*
157  * _wnoutrefresh --
158  *	Does the grunt work for wnoutrefresh to the given screen.
159  *	Copies the part of the window given by the rectangle
160  *	(begy, begx) to (maxy, maxx) at screen position (wbegy, wbegx).
161  */
162 static int
163 _wnoutrefresh(WINDOW *win, int begy, int begx, int wbegy, int wbegx,
164               int maxy, int maxx)
165 {
166 	SCREEN *screen = win->screen;
167 	short	sy, wy, wx, y_off, x_off, mx, dy_off, dx_off, endy;
168 	int newy, newx;
169 	__LINE	*wlp, *vlp, *dwlp;
170 	WINDOW	*sub_win, *orig, *swin, *dwin;
171 
172 #ifdef DEBUG
173 	__CTRACE(__CTRACE_REFRESH, "_wnoutrefresh: win %p, flags 0x%08x\n",
174 	    win, win->flags);
175 	__CTRACE(__CTRACE_REFRESH,
176 	    "_wnoutrefresh: (%d, %d), (%d, %d), (%d, %d)\n",
177 	    begy, begx, wbegy, wbegx, maxy, maxx);
178 #endif
179 
180 	if (screen->curwin)
181 		return OK;
182 
183 	swin = dwin = win;
184 	if (win->flags & __ISDERWIN)
185 		swin = win->orig;
186 
187 	/*
188 	 * Recurse through any sub-windows, mark as dirty lines on the parent
189 	 * window that are dirty on the sub-window and clear the dirty flag on
190 	 * the sub-window.
191 	 */
192 	if (dwin->orig == 0) {
193 		orig = dwin;
194 		for (sub_win = dwin->nextp; sub_win != orig;
195 		    sub_win = sub_win->nextp) {
196 			if (sub_win->flags & __ISDERWIN)
197 				continue;
198 #ifdef DEBUG
199 			__CTRACE(__CTRACE_REFRESH,
200 			    "wnout_refresh: win %p, sub_win %p\n",
201 			    orig, sub_win);
202 #endif
203 			for (sy = 0; sy < sub_win->maxy; sy++) {
204 				if (sub_win->alines[sy]->flags & __ISDIRTY) {
205 					orig->alines[sy + sub_win->begy - orig->begy]->flags
206 					    |= __ISDIRTY;
207 					sub_win->alines[sy]->flags
208 					    &= ~__ISDIRTY;
209 				}
210 				if (sub_win->alines[sy]->flags & __ISFORCED) {
211 					orig->alines[sy + sub_win->begy - orig->begy]->flags
212 					    |= __ISFORCED;
213 					sub_win->alines[sy]->flags
214 					    &= ~__ISFORCED;
215 				}
216 			}
217 		}
218 	}
219 
220 	/* Check that cursor position on "win" is valid for "__virtscr" */
221 	newy = wbegy + dwin->cury - begy;
222 	newx = wbegx + dwin->curx - begx;
223 	if (begy <= dwin->cury && dwin->cury < maxy
224 	    && 0 <= newy && newy < screen->__virtscr->maxy)
225 		screen->__virtscr->cury = newy;
226 	if (begx <= dwin->curx && dwin->curx < maxx
227 	    && 0 <= newx && newx < screen->__virtscr->maxx)
228 		screen->__virtscr->curx = newx;
229 
230 	/* Copy the window flags from "win" to "__virtscr" */
231 	if (dwin->flags & __CLEAROK) {
232 		if (dwin->flags & __FULLWIN)
233 			screen->__virtscr->flags |= __CLEAROK;
234 		dwin->flags &= ~__CLEAROK;
235 	}
236 	screen->__virtscr->flags &= ~__LEAVEOK;
237 	screen->__virtscr->flags |= dwin->flags;
238 
239 	if ((dwin->flags & __ISDERWIN) != 0)
240 		endy = begy + maxy;
241 	else
242 		endy = maxy;
243 
244 	for (wy = begy, y_off = wbegy, dy_off = 0; wy < endy &&
245 	    y_off < screen->__virtscr->maxy; wy++, y_off++, dy_off++)
246 	{
247 		wlp = swin->alines[wy];
248 		dwlp = dwin->alines[dy_off];
249 #ifdef DEBUG
250 		__CTRACE(__CTRACE_REFRESH,
251 		    "_wnoutrefresh: wy %d\tf %d\tl %d\tflags %x\n",
252 		    wy, *wlp->firstchp, *wlp->lastchp, wlp->flags);
253 
254 		char *_wintype;
255 
256 		if ((dwin->flags & __ISDERWIN) != 0)
257 			_wintype = "derwin";
258 		else
259 			_wintype = "dwin";
260 
261 		__CTRACE(__CTRACE_REFRESH,
262 		"_wnoutrefresh: %s wy %d\tf %d\tl %d\tflags %x\n",
263 		_wintype, dy_off, *dwlp->firstchp, *dwlp->lastchp, dwlp->flags);
264 		__CTRACE(__CTRACE_REFRESH,
265 		"_wnoutrefresh: %s maxx %d\tch_off %d wlp %p\n",
266 		_wintype, dwin->maxx, dwin->ch_off, wlp);
267 #endif
268 		if (((wlp->flags & (__ISDIRTY | __ISFORCED)) == 0) &&
269 		    ((dwlp->flags & (__ISDIRTY | __ISFORCED)) == 0))
270 			continue;
271 #ifdef DEBUG
272 		__CTRACE(__CTRACE_REFRESH,
273 		"_wnoutrefresh: line y_off %d (dy_off %d) is dirty\n",
274 			y_off, dy_off);
275 #endif
276 
277 		wlp = swin->alines[wy];
278 		vlp = screen->__virtscr->alines[y_off];
279 
280 		if ((*wlp->firstchp < maxx + swin->ch_off &&
281 		    *wlp->lastchp >= swin->ch_off) ||
282 		    ((((dwin->flags & __ISDERWIN) != 0) &&
283 		     (*dwlp->firstchp < dwin->maxx + dwin->ch_off &&
284 		      *dwlp->lastchp >= dwin->ch_off))))
285 		{
286 			/* Set start column */
287 			wx = begx;
288 			x_off = wbegx;
289 			dx_off = 0;
290 			/*
291 			 * if a derwin then source change pointers aren't
292 			 * relevant.
293 			 */
294 			if ((dwin->flags & __ISDERWIN) != 0)
295 				mx = wx + maxx;
296 			else {
297 				if (*wlp->firstchp - swin->ch_off > 0) {
298 					wx += *wlp->firstchp - swin->ch_off;
299 					x_off += *wlp->firstchp - swin->ch_off;
300 				}
301 				mx = maxx;
302 				if (mx > *wlp->lastchp - swin->ch_off + 1)
303 					mx = *dwlp->lastchp - dwin->ch_off + 1;
304 				if (x_off + (mx - wx) > screen->__virtscr->maxx)
305 					mx -= (x_off + maxx) -
306 					    screen->__virtscr->maxx;
307 			}
308 
309 			/* Copy line from "win" to "__virtscr". */
310 			while (wx < mx) {
311 #ifdef DEBUG
312 				__CTRACE(__CTRACE_REFRESH,
313 				    "_wnoutrefresh: copy from %d, "
314 				    "%d to %d, %d: %s, 0x%x",
315 				    wy, wx, y_off, x_off,
316 				    unctrl(wlp->line[wx].ch),
317 				    wlp->line[wx].attr);
318 				__CTRACE(__CTRACE_REFRESH, " (curdest %s, 0x%x)",
319 				    unctrl(vlp->line[x_off].ch),
320 				    vlp->line[x_off].attr);
321 #endif
322 				/* Copy character */
323 				vlp->line[x_off].ch = wlp->line[wx].ch;
324 				/* Copy attributes  */
325 				vlp->line[x_off].attr = wlp->line[wx].attr;
326 				/* Check for nca conflict with colour */
327 				if ((vlp->line[x_off].attr & __COLOR) &&
328 				    (vlp->line[x_off].attr & screen->nca))
329 					vlp->line[x_off].attr &= ~__COLOR;
330 				if (win->flags & __ISDERWIN) {
331 					dwlp->line[dx_off].ch =
332 						wlp->line[wx].ch;
333 					dwlp->line[dx_off].attr =
334 						wlp->line[wx].attr;
335 				}
336 
337 #ifdef HAVE_WCHAR
338 				if (wlp->line[wx].ch
339 				    == (wchar_t)btowc((int) win->bch)) {
340 					vlp->line[x_off].ch = win->bch;
341 					SET_WCOL(vlp->line[x_off], 1);
342 					if (_cursesi_copy_nsp(win->bnsp,
343 							      &vlp->line[x_off])
344 					    == ERR)
345 						return ERR;
346 					if (win->flags & __ISDERWIN) {
347 						dwlp->line[dx_off].ch =
348 							win->bch;
349 						SET_WCOL(dwlp->line[dx_off], 1);
350 						if (_cursesi_copy_nsp(win->bnsp,
351 						     &dwlp->line[dx_off])
352 						    == ERR)
353 							return ERR;
354 					}
355 				}
356 #endif /* HAVE_WCHAR */
357 #ifdef DEBUG
358 				__CTRACE(__CTRACE_REFRESH, " = %s, 0x%x\n",
359 				    unctrl(vlp->line[x_off].ch),
360 				    vlp->line[x_off].attr);
361 #endif
362 				wx++;
363 				x_off++;
364 				dx_off++;
365 			}
366 
367 			/* Set flags on "__virtscr" and unset on "win". */
368 			if (wlp->flags & __ISPASTEOL)
369 				vlp->flags |= __ISPASTEOL;
370 			else
371 				vlp->flags &= ~__ISPASTEOL;
372 			if (wlp->flags & __ISDIRTY)
373 				vlp->flags |= __ISDIRTY;
374 			if (wlp->flags & __ISFORCED)
375 				vlp->flags |= __ISFORCED;
376 
377 #ifdef DEBUG
378 			__CTRACE(__CTRACE_REFRESH,
379 			    "win: firstch = %d, lastch = %d\n",
380 			    *wlp->firstchp, *wlp->lastchp);
381 			if (win->flags & __ISDERWIN) {
382 				__CTRACE(__CTRACE_REFRESH,
383 				    "derwin: fistch = %d, lastch = %d\n",
384 				    *dwlp->firstchp, *dwlp->lastchp);
385 			}
386 #endif
387 			/* Set change pointers on "__virtscr". */
388 			if (*vlp->firstchp >
389 				*wlp->firstchp + wbegx - win->ch_off)
390 					*vlp->firstchp =
391 					    *wlp->firstchp + wbegx - win->ch_off;
392 			if (*vlp->lastchp <
393 				*wlp->lastchp + wbegx - win->ch_off)
394 					*vlp->lastchp =
395 					    *wlp->lastchp + wbegx - win->ch_off;
396 
397 			if (win->flags & __ISDERWIN) {
398 				if (*vlp->firstchp >
399 				    *dwlp->firstchp + wbegx - dwin->ch_off)
400 				{
401 					*vlp->firstchp =
402 					    *dwlp->firstchp + wbegx
403 						- dwin->ch_off;
404 					vlp->flags |= __ISDIRTY;
405 				}
406 
407 				if (*vlp->lastchp <
408 				    *dwlp->lastchp + wbegx - dwin->ch_off)
409 				{
410 					*vlp->lastchp = *dwlp->lastchp
411 					    + wbegx - dwin->ch_off;
412 					vlp->flags |= __ISDIRTY;
413 				}
414 			}
415 
416 #ifdef DEBUG
417 			__CTRACE(__CTRACE_REFRESH,
418 			    "__virtscr: firstch = %d, lastch = %d\n",
419 			    *vlp->firstchp, *vlp->lastchp);
420 #endif
421 			/*
422 			 * Unset change pointers only if a window and we
423 			 * are not forcing a redraw. A pad can be displayed
424 			 * again without any of the contents changing.
425 			 */
426 			if ((!(win->flags & __ISPAD)) ||
427 			    ((wlp->flags & __ISFORCED) == __ISFORCED))
428 			{
429 				/* Set change pointers on "win". */
430 				if (*wlp->firstchp >= win->ch_off)
431 					*wlp->firstchp = maxx + win->ch_off;
432 				if (*wlp->lastchp < maxx + win->ch_off)
433 					*wlp->lastchp = win->ch_off;
434 				if ((*wlp->lastchp < *wlp->firstchp) ||
435 				    (*wlp->firstchp >= maxx + win->ch_off) ||
436 				    (*wlp->lastchp <= win->ch_off)) {
437 #ifdef DEBUG
438 					__CTRACE(__CTRACE_REFRESH,
439 					    "_wnoutrefresh: "
440 					    "line %d notdirty\n", wy);
441 #endif
442 					wlp->flags &= ~(__ISDIRTY | __ISFORCED);
443 				}
444 			}
445 		}
446 	}
447 	return OK;
448 }
449 
450 /*
451  * wrefresh --
452  *	Make the current screen look like "win" over the area covered by
453  *	win.
454  */
455 int
456 wrefresh(WINDOW *win)
457 {
458 	int retval;
459 	int pbegx, pbegy;
460 
461 #ifdef DEBUG
462 	__CTRACE(__CTRACE_REFRESH, "wrefresh: win %p\n", win);
463 #endif
464 
465 	_cursesi_screen->curwin = (win == _cursesi_screen->curscr);
466 	if (!_cursesi_screen->curwin) {
467 		pbegx = pbegy = 0;
468 		if ((win->flags & __ISDERWIN) == __ISDERWIN) {
469 			pbegx = win->derx;
470 			pbegy = win->dery;
471 #ifdef DEBUG
472 	__CTRACE(__CTRACE_REFRESH, "wrefresh: derwin, begy = %d, begx = %x\n",
473 		pbegy, pbegx);
474 #endif
475 		}
476 		retval = _wnoutrefresh(win, pbegy, pbegx, win->begy, win->begx,
477 		    win->maxy, win->maxx);
478 	} else
479 		retval = OK;
480 	if (retval == OK) {
481 		retval = doupdate();
482 		if (!(win->flags & __LEAVEOK)) {
483 			win->cury = max(0, curscr->cury - win->begy);
484 			win->curx = max(0, curscr->curx - win->begx);
485 		}
486 	}
487 	_cursesi_screen->curwin = 0;
488 	return retval;
489 }
490 
491  /*
492  * prefresh --
493  *	Make the current screen look like "pad" over the area coverd by
494  *	the specified area of pad.
495  */
496 int
497 prefresh(WINDOW *pad, int pbegy, int pbegx, int sbegy, int sbegx,
498 	int smaxy, int smaxx)
499 {
500 	int retval;
501 
502 #ifdef DEBUG
503 	__CTRACE(__CTRACE_REFRESH, "prefresh: pad %p, flags 0x%08x\n",
504 	    pad, pad->flags);
505 #endif
506 	/* Retain values in case pechochar() is called. */
507 	pad->pbegy = pbegy;
508 	pad->pbegx = pbegx;
509 	pad->sbegy = sbegy;
510 	pad->sbegx = sbegx;
511 	pad->smaxy = smaxy;
512 	pad->smaxx = smaxx;
513 
514 	/* Use pnoutrefresh() to avoid duplicating code here */
515 	retval = pnoutrefresh(pad, pbegy, pbegx, sbegy, sbegx, smaxy, smaxx);
516 	if (retval == OK) {
517 		retval = doupdate();
518 		if (!(pad->flags & __LEAVEOK)) {
519 			pad->cury = max(0, pbegy + (curscr->cury - sbegy));
520 			pad->curx = max(0, pbegx + (curscr->curx - sbegx));
521 		}
522 	}
523 	return retval;
524 }
525 
526 /*
527  * doupdate --
528  *	Make the current screen look like the virtual window "__virtscr".
529  */
530 int
531 doupdate(void)
532 {
533 	WINDOW	*win;
534 	__LINE	*wlp, *vlp;
535 	short	 wy;
536 	int	 dnum, was_cleared, changed;
537 #ifdef HAVE_WCHAR
538 	__LDATA *lp;
539 	nschar_t *np;
540 	int x;
541 #endif /* HAVE_WCHAR */
542 
543 	/* Check if we need to restart ... */
544 	if (_cursesi_screen->endwin)
545 		__restartwin();
546 
547 	if (_cursesi_screen->curwin)
548 		win = curscr;
549 	else
550 		win = _cursesi_screen->__virtscr;
551 
552 	/* Initialize loop parameters. */
553 	_cursesi_screen->ly = curscr->cury;
554 	_cursesi_screen->lx = curscr->curx;
555 	wy = 0;
556 
557 	if (!_cursesi_screen->curwin) {
558 		for (wy = 0; wy < win->maxy; wy++) {
559 			wlp = win->alines[wy];
560 			if (wlp->flags & __ISDIRTY) {
561 #ifndef HAVE_WCHAR
562 				wlp->hash = __hash(wlp->line,
563 				    (size_t)(win->maxx * __LDATASIZE));
564 #else
565 				wlp->hash = 0;
566 				for ( x = 0; x < win->maxx; x++ ) {
567 					lp = &wlp->line[ x ];
568 					wlp->hash = __hash_more( &lp->ch,
569 						sizeof(wchar_t), wlp->hash );
570 					wlp->hash = __hash_more( &lp->attr,
571 						sizeof(attr_t), wlp->hash );
572 					np = lp->nsp;
573 					if (np) {
574 						while (np) {
575 							wlp->hash
576 							    = __hash_more(
577 								&np->ch,
578 								sizeof(wchar_t),
579 								wlp->hash);
580 							np = np->next;
581 						}
582 					}
583 				}
584 #endif /* HAVE_WCHAR */
585 			}
586 		}
587 	}
588 
589 	was_cleared = 0;
590 	if ((win->flags & __CLEAROK) || (curscr->flags & __CLEAROK) ||
591 	    _cursesi_screen->curwin)
592 	{
593 		if (curscr->wattr & __COLOR)
594 			__unsetattr(0);
595 		tputs(clear_screen, 0, __cputchar);
596 		_cursesi_screen->ly = 0;
597 		_cursesi_screen->lx = 0;
598 		if (!_cursesi_screen->curwin) {
599 			curscr->flags &= ~__CLEAROK;
600 			curscr->cury = 0;
601 			curscr->curx = 0;
602 			werase(curscr);
603 		}
604 		__touchwin(win);
605 		win->flags &= ~__CLEAROK;
606 		/* note we cleared for later */
607 		was_cleared = 1;
608 	}
609 	if (!cursor_address) {
610 		if (win->curx != 0)
611 			__cputchar('\n');
612 		if (!_cursesi_screen->curwin)
613 			werase(curscr);
614 	}
615 #ifdef DEBUG
616 	__CTRACE(__CTRACE_REFRESH, "doupdate: (%p): curwin = %d\n", win,
617 	    _cursesi_screen->curwin);
618 	__CTRACE(__CTRACE_REFRESH, "doupdate: \tfirstch\tlastch\n");
619 #endif
620 
621 	if (!_cursesi_screen->curwin) {
622 		/*
623 		 * Invoke quickch() only if more than a quarter of the lines
624 		 * in the window are dirty.
625 		 */
626 		for (wy = 0, dnum = 0; wy < win->maxy; wy++)
627 			if (win->alines[wy]->flags & __ISDIRTY)
628 				dnum++;
629 		if (!__noqch && dnum > (int) win->maxy / 4)
630 			quickch();
631 	}
632 
633 #ifdef DEBUG
634 	{
635 		int	i, j;
636 
637 		__CTRACE(__CTRACE_REFRESH,
638 		    "#####################################\n");
639 		__CTRACE(__CTRACE_REFRESH,
640 		    "stdscr(%p)-curscr(%p)-__virtscr(%p)\n",
641 		    stdscr, curscr, _cursesi_screen->__virtscr);
642 		for (i = 0; i < curscr->maxy; i++) {
643 			__CTRACE(__CTRACE_REFRESH, "C: %d:", i);
644 			__CTRACE(__CTRACE_REFRESH, " 0x%x \n",
645 			    curscr->alines[i]->hash);
646 			for (j = 0; j < curscr->maxx; j++)
647 				__CTRACE(__CTRACE_REFRESH, "%c",
648 				    curscr->alines[i]->line[j].ch);
649 			__CTRACE(__CTRACE_REFRESH, "\n");
650 			__CTRACE(__CTRACE_REFRESH, " attr:");
651 			for (j = 0; j < curscr->maxx; j++)
652 				__CTRACE(__CTRACE_REFRESH, " %x",
653 				    curscr->alines[i]->line[j].attr);
654 			__CTRACE(__CTRACE_REFRESH, "\n");
655 			__CTRACE(__CTRACE_REFRESH, "W: %d:", i);
656 			__CTRACE(__CTRACE_REFRESH, " 0x%x \n",
657 			    win->alines[i]->hash);
658 			__CTRACE(__CTRACE_REFRESH, " 0x%x ",
659 			    win->alines[i]->flags);
660 			for (j = 0; j < win->maxx; j++)
661 				__CTRACE(__CTRACE_REFRESH, "%c",
662 				    win->alines[i]->line[j].ch);
663 			__CTRACE(__CTRACE_REFRESH, "\n");
664 			__CTRACE(__CTRACE_REFRESH, " attr:");
665 			for (j = 0; j < win->maxx; j++)
666 				__CTRACE(__CTRACE_REFRESH, " %x",
667 				    win->alines[i]->line[j].attr);
668 			__CTRACE(__CTRACE_REFRESH, "\n");
669 #ifdef HAVE_WCHAR
670 			__CTRACE(__CTRACE_REFRESH, " nsp:");
671 			for (j = 0; j < curscr->maxx; j++)
672 				__CTRACE(__CTRACE_REFRESH, " %p",
673 				    win->alines[i]->line[j].nsp);
674 			__CTRACE(__CTRACE_REFRESH, "\n");
675 			__CTRACE(__CTRACE_REFRESH, " bnsp:");
676 			for (j = 0; j < curscr->maxx; j++)
677 				__CTRACE(__CTRACE_REFRESH, " %p",
678 				    win->bnsp);
679 			__CTRACE(__CTRACE_REFRESH, "\n");
680 #endif /* HAVE_WCHAR */
681 		}
682 	}
683 #endif /* DEBUG */
684 
685 	changed = 0;
686 	for (wy = 0; wy < win->maxy; wy++) {
687 		wlp = win->alines[wy];
688 		vlp = _cursesi_screen->__virtscr->alines[win->begy + wy];
689 /* XXX: remove this debug */
690 #ifdef DEBUG
691 		__CTRACE(__CTRACE_REFRESH,
692 		    "doupdate: wy %d\tf: %d\tl:%d\tflags %x\n",
693 		    wy, *wlp->firstchp, *wlp->lastchp, wlp->flags);
694 #endif /* DEBUG */
695 		if (!_cursesi_screen->curwin)
696 			curscr->alines[wy]->hash = wlp->hash;
697 		if (wlp->flags & __ISDIRTY || wlp->flags & __ISFORCED) {
698 #ifdef DEBUG
699 			__CTRACE(__CTRACE_REFRESH,
700 			    "doupdate: [ISDIRTY]wy:%d\tf:%d\tl:%d\n", wy,
701 			    *wlp->firstchp, *wlp->lastchp);
702 #endif /* DEBUG */
703 			/*
704 			 * We have just cleared so don't force an update
705 			 * otherwise we spray neeedless blanks to a cleared
706 			 * screen.
707 			 */
708 			if (was_cleared == 1)
709 				win->alines[wy]->flags &= ~__ISFORCED;
710 
711 			if (makech(wy) == ERR)
712 				return ERR;
713 			else {
714 				if (*wlp->firstchp >= 0)
715 					*wlp->firstchp = win->maxx;
716 				if (*wlp->lastchp < win->maxx)
717 					*wlp->lastchp = win->ch_off;
718 				if (*wlp->lastchp < *wlp->firstchp) {
719 #ifdef DEBUG
720 					__CTRACE(__CTRACE_REFRESH,
721 					    "doupdate: line %d notdirty\n", wy);
722 #endif /* DEBUG */
723 					wlp->flags &= ~(__ISDIRTY | __ISFORCED);
724 				}
725 
726 				/* Check if we have input after
727 				 * changing N lines. */
728 				if (_cursesi_screen->checkfd != -1 &&
729 				    ++changed == CHECK_INTERVAL)
730 				{
731 					struct pollfd fds[1];
732 
733 					/* If we have input, abort. */
734 					fds[0].fd = _cursesi_screen->checkfd;
735 					fds[0].events = POLLIN;
736 					if (poll(fds, 1, 0) > 0)
737 						goto cleanup;
738 					changed = 0;
739 				}
740 			}
741 		}
742 
743 		/*
744 		 * virtscr is now synced for the line, unset the change
745 		 * pointers.
746 		 */
747 		if (*vlp->firstchp >= 0)
748 			*vlp->firstchp = _cursesi_screen->__virtscr->maxx;
749 		if (*vlp->lastchp <= _cursesi_screen->__virtscr->maxx)
750 			*vlp->lastchp = 0;
751 
752 #ifdef DEBUG
753 		__CTRACE(__CTRACE_REFRESH, "\t%d\t%d\n",
754 		    *wlp->firstchp, *wlp->lastchp);
755 #endif /* DEBUG */
756 	}
757 
758 #ifdef DEBUG
759 	__CTRACE(__CTRACE_REFRESH, "doupdate: ly=%d, lx=%d\n",
760 	    _cursesi_screen->ly, _cursesi_screen->lx);
761 #endif /* DEBUG */
762 
763 	if (_cursesi_screen->curwin)
764 		domvcur(win, _cursesi_screen->ly, _cursesi_screen->lx,
765 			win->cury, win->curx);
766 	else {
767 		if (win->flags & __LEAVEOK) {
768 			curscr->cury = _cursesi_screen->ly;
769 			curscr->curx = _cursesi_screen->lx;
770 		} else {
771 			domvcur(win, _cursesi_screen->ly, _cursesi_screen->lx,
772 				win->cury, win->curx);
773 			curscr->cury = win->cury;
774 			curscr->curx = win->curx;
775 		}
776 	}
777 
778 cleanup:
779 	/* Don't leave the screen with attributes set. */
780 	__unsetattr(0);
781 #ifdef DEBUG
782 #ifdef HAVE_WCHAR
783 	{
784 		int	i, j;
785 
786 		__CTRACE(__CTRACE_REFRESH,
787 		    "***********after*****************\n");
788 		__CTRACE(__CTRACE_REFRESH,
789 		    "stdscr(%p)-curscr(%p)-__virtscr(%p)\n",
790 		    stdscr, curscr, _cursesi_screen->__virtscr);
791 		for (i = 0; i < curscr->maxy; i++) {
792 			for (j = 0; j < curscr->maxx; j++)
793 				__CTRACE(__CTRACE_REFRESH,
794 				    "[%d,%d](%x,%x,%p)-(%x,%x,%p)\n",
795 				    i, j,
796 				    curscr->alines[i]->line[j].ch,
797 				    curscr->alines[i]->line[j].attr,
798 				    curscr->alines[i]->line[j].nsp,
799 				    _cursesi_screen->__virtscr->alines[i]->line[j].ch,
800 				    _cursesi_screen->__virtscr->alines[i]->line[j].attr,
801 				    _cursesi_screen->__virtscr->alines[i]->line[j].nsp);
802 		}
803 	}
804 #endif /* HAVE_WCHAR */
805 #endif /* DEBUG */
806 	return fflush(_cursesi_screen->outfd) == EOF ? ERR : OK;
807 }
808 
809 static void
810 putattr(__LDATA *nsp)
811 {
812 	attr_t	off, on;
813 
814 #ifdef DEBUG
815 	__CTRACE(__CTRACE_REFRESH,
816 	    "makech: have attr %08x, need attr %08x\n",
817 	    curscr->wattr
818 #ifndef HAVE_WCHAR
819 	    & __ATTRIBUTES
820 #else
821 	    & WA_ATTRIBUTES
822 #endif
823 	    ,  nsp->attr
824 #ifndef HAVE_WCHAR
825 	    & __ATTRIBUTES
826 #else
827 	    & WA_ATTRIBUTES
828 #endif
829 	    );
830 #endif
831 
832 	off = (~nsp->attr & curscr->wattr)
833 #ifndef HAVE_WCHAR
834 	    & __ATTRIBUTES
835 #else
836 	    & WA_ATTRIBUTES
837 #endif
838 	    ;
839 
840 	/*
841 	 * Unset attributes as appropriate.  Unset first
842 	 * so that the relevant attributes can be reset
843 	 * (because 'me' unsets 'mb', 'md', 'mh', 'mk',
844 	 * 'mp' and 'mr').  Check to see if we also turn off
845 	 * standout, attributes and colour.
846 	 */
847 	if (off & __TERMATTR && exit_attribute_mode != NULL) {
848 		tputs(exit_attribute_mode, 0, __cputchar);
849 		curscr->wattr &= __mask_me;
850 		off &= __mask_me;
851 	}
852 
853 	/*
854 	 * Exit underscore mode if appropriate.
855 	 * Check to see if we also turn off standout,
856 	 * attributes and colour.
857 	 */
858 	if (off & __UNDERSCORE && exit_underline_mode != NULL) {
859 		tputs(exit_underline_mode, 0, __cputchar);
860 		curscr->wattr &= __mask_ue;
861 		off &= __mask_ue;
862 	}
863 
864 	/*
865 	 * Exit standout mode as appropriate.
866 	 * Check to see if we also turn off underscore,
867 	 * attributes and colour.
868 	 * XXX
869 	 * Should use uc if so/se not available.
870 	 */
871 	if (off & __STANDOUT && exit_standout_mode != NULL) {
872 		tputs(exit_standout_mode, 0, __cputchar);
873 		curscr->wattr &= __mask_se;
874 		off &= __mask_se;
875 	}
876 
877 	if (off & __ALTCHARSET && exit_alt_charset_mode != NULL) {
878 		tputs(exit_alt_charset_mode, 0, __cputchar);
879 		curscr->wattr &= ~__ALTCHARSET;
880 	}
881 
882 	/* Set/change colour as appropriate. */
883 	if (__using_color)
884 		__set_color(curscr, nsp->attr & __COLOR);
885 
886 	on = (nsp->attr & ~curscr->wattr)
887 #ifndef HAVE_WCHAR
888 	    & __ATTRIBUTES
889 #else
890 	    & WA_ATTRIBUTES
891 #endif
892 	    ;
893 
894 	/*
895 	 * Enter standout mode if appropriate.
896 	 */
897 	if (on & __STANDOUT &&
898 	    enter_standout_mode != NULL &&
899 	    exit_standout_mode != NULL)
900 	{
901 		tputs(enter_standout_mode, 0, __cputchar);
902 		curscr->wattr |= __STANDOUT;
903 	}
904 
905 	/*
906 	 * Enter underscore mode if appropriate.
907 	 * XXX
908 	 * Should use uc if us/ue not available.
909 	 */
910 	if (on & __UNDERSCORE &&
911 	    enter_underline_mode != NULL &&
912 	    exit_underline_mode != NULL)
913 	{
914 		tputs(enter_underline_mode, 0, __cputchar);
915 		curscr->wattr |= __UNDERSCORE;
916 	}
917 
918 	/*
919 	 * Set other attributes as appropriate.
920 	 */
921 	if (exit_attribute_mode != NULL) {
922 		if (on & __BLINK && enter_blink_mode != NULL)
923 		{
924 			tputs(enter_blink_mode, 0, __cputchar);
925 			curscr->wattr |= __BLINK;
926 		}
927 		if (on & __BOLD && enter_bold_mode != NULL)
928 		{
929 			tputs(enter_bold_mode, 0, __cputchar);
930 			curscr->wattr |= __BOLD;
931 		}
932 		if (on & __DIM && enter_dim_mode != NULL)
933 		{
934 			tputs(enter_dim_mode, 0, __cputchar);
935 			curscr->wattr |= __DIM;
936 		}
937 		if (on & __BLANK && enter_secure_mode != NULL)
938 		{
939 			tputs(enter_secure_mode, 0, __cputchar);
940 			curscr->wattr |= __BLANK;
941 		}
942 		if (on & __PROTECT && enter_protected_mode != NULL)
943 		{
944 			tputs(enter_protected_mode, 0, __cputchar);
945 			curscr->wattr |= __PROTECT;
946 		}
947 		if (on & __REVERSE && enter_reverse_mode != NULL)
948 		{
949 			tputs(enter_reverse_mode, 0, __cputchar);
950 			curscr->wattr |= __REVERSE;
951 		}
952 #ifdef HAVE_WCHAR
953 		if (on & WA_TOP && enter_top_hl_mode != NULL)
954 		{
955 			tputs(enter_top_hl_mode, 0, __cputchar);
956 			curscr->wattr |= WA_TOP;
957 		}
958 		if (on & WA_LOW && enter_low_hl_mode != NULL)
959 		{
960 			tputs(enter_low_hl_mode, 0, __cputchar);
961 			curscr->wattr |= WA_LOW;
962 		}
963 		if (on & WA_LEFT && enter_left_hl_mode != NULL)
964 		{
965 			tputs(enter_left_hl_mode, 0, __cputchar);
966 			curscr->wattr |= WA_LEFT;
967 		}
968 		if (on & WA_RIGHT && enter_right_hl_mode != NULL)
969 		{
970 			tputs(enter_right_hl_mode, 0, __cputchar);
971 			curscr->wattr |= WA_RIGHT;
972 		}
973 		if (on & WA_HORIZONTAL && enter_horizontal_hl_mode != NULL)
974 		{
975 			tputs(enter_horizontal_hl_mode, 0, __cputchar);
976 			curscr->wattr |= WA_HORIZONTAL;
977 		}
978 		if (on & WA_VERTICAL && enter_vertical_hl_mode != NULL)
979 		{
980 			tputs(enter_vertical_hl_mode, 0, __cputchar);
981 			curscr->wattr |= WA_VERTICAL;
982 		}
983 #endif /* HAVE_WCHAR */
984 	}
985 
986 	/* Enter/exit altcharset mode as appropriate. */
987 	if (on & __ALTCHARSET && enter_alt_charset_mode != NULL &&
988 	    exit_alt_charset_mode != NULL) {
989 		tputs(enter_alt_charset_mode, 0, __cputchar);
990 		curscr->wattr |= __ALTCHARSET;
991 	}
992 }
993 
994 static void
995 putattr_out(__LDATA *nsp)
996 {
997 
998 	if (underline_char &&
999 	    ((nsp->attr & __STANDOUT) || (nsp->attr & __UNDERSCORE)))
1000 	{
1001 		__cputchar('\b');
1002 		tputs(underline_char, 0, __cputchar);
1003 	}
1004 }
1005 
1006 static int
1007 putch(__LDATA *nsp, __LDATA *csp, int wy, int wx)
1008 {
1009 
1010 	if (csp != NULL)
1011 		putattr(nsp);
1012 
1013 	if (!_cursesi_screen->curwin && csp) {
1014 		csp->attr = nsp->attr;
1015 		csp->ch = nsp->ch;
1016 #ifdef HAVE_WCHAR
1017 		if (_cursesi_copy_nsp(nsp->nsp, csp) == ERR)
1018 			return ERR;
1019 #endif /* HAVE_WCHAR */
1020 	}
1021 
1022 #ifndef HAVE_WCHAR
1023 	__cputchar((int)nsp->ch);
1024 #else
1025 	if (WCOL(*nsp) <= 0)
1026 		goto out;
1027 	__cputwchar((int)nsp->ch);
1028 #ifdef DEBUG
1029 	__CTRACE(__CTRACE_REFRESH,
1030 	    "makech: (%d,%d)putwchar(0x%x)\n", wy, wx - 1, nsp->ch);
1031 #endif /* DEBUG */
1032 
1033 	/* Output non-spacing characters for the cell. */
1034 	__cursesi_putnsp(nsp->nsp, wy, wx);
1035 out:
1036 #endif /* HAVE_WCHAR */
1037 
1038 	if (csp != NULL)
1039 		putattr_out(nsp);
1040 	return OK;
1041 }
1042 
1043 static int
1044 putchbr(__LDATA *nsp, __LDATA *csp, __LDATA *psp, int wy, int wx)
1045 {
1046 	int error, cw, pcw;
1047 
1048 	/* Can safely print to bottom right corner. */
1049 	if (!auto_right_margin)
1050 		return putch(nsp, csp, wy, wx);
1051 
1052 	/* Disable auto margins temporarily. */
1053 	if (enter_am_mode && exit_am_mode) {
1054 		tputs(exit_am_mode, 0, __cputchar);
1055 		error = putch(nsp, csp, wy, wx);
1056 		tputs(enter_am_mode, 0, __cputchar);
1057 		return error;
1058 	}
1059 
1060 	/* We need to insert characters. */
1061 #ifdef HAVE_WCHAR
1062 	cw = WCOL(*nsp);
1063 	pcw = WCOL(*psp);
1064 	if (cw < 1 || pcw < 1)
1065 		return ERR; /* Nothing to insert */
1066 
1067 	/* When inserting a wide character, we need something other than
1068 	 * insert_character. */
1069 	if (pcw > 1 &&
1070 	    !(parm_ich != NULL ||
1071 	    (enter_insert_mode != NULL && exit_insert_mode != NULL)))
1072 		return ERR;
1073 #else
1074 	cw = pcw = 1;
1075 #endif /* HAVE_WCHAR */
1076 
1077 	/* Write the corner character at wx - pcw. */
1078 	__mvcur(wy, wx, wy, wx - pcw, 1);
1079 	if (putch(nsp, csp, wy, wx) == ERR)
1080 		return ERR;
1081 
1082 	/* Move cursor back. */
1083 	__mvcur(wy, wx - pcw + cw, wy, wx - cw, 1);
1084 
1085 	putattr(psp);
1086 
1087 	/* Enter insert mode. */
1088 	if (pcw == 1 && insert_character != NULL)
1089 		tputs(insert_character, 0, __cputchar);
1090 	else if (parm_ich != NULL)
1091 		tputs(tiparm(parm_ich, (long)pcw), 0, __cputchar);
1092 	else if (enter_insert_mode != NULL && exit_insert_mode != NULL)
1093 		tputs(enter_insert_mode, 0, __cputchar);
1094 	else
1095 		return ERR;
1096 
1097 	/* Insert the old character back. */
1098 	error = putch(psp, NULL, wy, wx - pcw);
1099 
1100 	/* Exit insert mode. */
1101 	if (insert_character != NULL || parm_ich != NULL)
1102 		;
1103 	else if (enter_insert_mode != NULL && exit_insert_mode != NULL)
1104 		tputs(exit_insert_mode, 0, __cputchar);
1105 
1106 	putattr_out(psp);
1107 
1108 	return error;
1109 }
1110 
1111 /*
1112  * makech --
1113  *	Make a change on the screen.
1114  */
1115 static int
1116 makech(int wy)
1117 {
1118 	WINDOW	*win;
1119 	static __LDATA blank;
1120 	__LDATA *nsp, *csp, *cp, *cep, *fsp;
1121 	__LINE *wlp;
1122 	size_t	clsp, nlsp;	/* Last space in lines. */
1123 	int	lch, wx, chw;
1124 	const char	*ce;
1125 	attr_t	lspc;		/* Last space colour */
1126 
1127 #ifdef __GNUC__
1128 	nlsp = lspc = 0;	/* XXX gcc -Wuninitialized */
1129 #endif
1130 	if (_cursesi_screen->curwin)
1131 		win = curscr;
1132 	else
1133 		win = __virtscr;
1134 #ifdef HAVE_WCHAR
1135 	blank.ch = (wchar_t)btowc((int) win->bch);
1136 	blank.attr = 0;
1137 	if (_cursesi_copy_nsp(win->bnsp, &blank) == ERR)
1138 		return ERR;
1139 	SET_WCOL(blank, 1);
1140 #endif /* HAVE_WCHAR */
1141 #ifdef DEBUG
1142 #if HAVE_WCHAR
1143 	{
1144 		int x;
1145 		__LDATA *lp, *vlp;
1146 
1147 		__CTRACE(__CTRACE_REFRESH,
1148 		    "[makech-before]wy=%d,curscr(%p)-__virtscr(%p)\n",
1149 		    wy, curscr, __virtscr);
1150 		for (x = 0; x < curscr->maxx; x++) {
1151 			lp = &curscr->alines[wy]->line[x];
1152 			vlp = &__virtscr->alines[wy]->line[x];
1153 			__CTRACE(__CTRACE_REFRESH,
1154 			    "[%d,%d](%x,%x,%x,%x,%p)-"
1155 			    "(%x,%x,%x,%x,%p)\n",
1156 			    wy, x, lp->ch, lp->attr,
1157 			    win->bch, win->battr, lp->nsp,
1158 			    vlp->ch, vlp->attr,
1159 			    win->bch, win->battr, vlp->nsp);
1160 		}
1161 	}
1162 #endif /* HAVE_WCHAR */
1163 #endif /* DEBUG */
1164 	/* Is the cursor still on the end of the last line? */
1165 	if (wy > 0 && curscr->alines[wy - 1]->flags & __ISPASTEOL) {
1166 		domvcur(win, _cursesi_screen->ly, _cursesi_screen->lx,
1167 			_cursesi_screen->ly + 1, 0);
1168 		_cursesi_screen->ly++;
1169 		_cursesi_screen->lx = 0;
1170 	}
1171 	wlp = win->alines[wy];
1172 	wx = *win->alines[wy]->firstchp;
1173 	if (wx < 0)
1174 		wx = 0;
1175 	else
1176 		if (wx >= win->maxx)
1177 			return (OK);
1178 	lch = *win->alines[wy]->lastchp;
1179 	if (lch < 0)
1180 		return OK;
1181 	else
1182 		if (lch >= (int) win->maxx)
1183 			lch = win->maxx - 1;
1184 
1185 	if (_cursesi_screen->curwin) {
1186 		csp = &blank;
1187 #ifdef DEBUG
1188 		__CTRACE(__CTRACE_REFRESH, "makech: csp is blank\n");
1189 #endif /* DEBUG */
1190 	} else {
1191 		csp = &curscr->alines[wy]->line[wx];
1192 #ifdef DEBUG
1193 		__CTRACE(__CTRACE_REFRESH,
1194 		    "makech: csp is on curscr:(%d,%d)\n", wy, wx);
1195 #endif /* DEBUG */
1196 	}
1197 
1198 	nsp = fsp = &win->alines[wy]->line[wx];
1199 #ifdef DEBUG
1200 	if (_cursesi_screen->curwin)
1201 		__CTRACE(__CTRACE_REFRESH,
1202 		    "makech: nsp is at curscr:(%d,%d)\n", wy, wx);
1203 	else
1204 		__CTRACE(__CTRACE_REFRESH,
1205 		    "makech: nsp is at __virtscr:(%d,%d)\n", wy, wx);
1206 #endif /* DEBUG */
1207 	if (clr_eol && !_cursesi_screen->curwin) {
1208 		cp = &win->alines[wy]->line[win->maxx - 1];
1209 		lspc = cp->attr & __COLOR;
1210 #ifndef HAVE_WCHAR
1211 		while (cp->ch == ' ' && cp->attr == lspc) /* XXX */
1212 			if (cp-- <= win->alines[wy]->line)
1213 				break;
1214 #else
1215 		while (cp->ch == ( wchar_t )btowc(( int )' ' )
1216 				&& ( cp->attr & WA_ATTRIBUTES ) == lspc)
1217 			if (cp-- <= win->alines[wy]->line)
1218 				break;
1219 #endif /* HAVE_WCHAR */
1220 		if (win->alines[wy]->line > cp)
1221 			nlsp = 0;
1222 		else
1223 			nlsp = cp - win->alines[wy]->line;
1224 	}
1225 	if (!_cursesi_screen->curwin)
1226 		ce = clr_eol;
1227 	else
1228 		ce = NULL;
1229 
1230 	while (wx <= lch) {
1231 #ifdef DEBUG
1232 #ifndef HAVE_WCHAR
1233 		__CTRACE(__CTRACE_REFRESH, "makech: wx=%d,lch=%d\n", wx, lch);
1234 #else
1235 		__CTRACE(__CTRACE_REFRESH, "makech: nsp=(%x,%x,%x,%x,%p)\n",
1236 			nsp->ch, nsp->attr, win->bch, win->battr, nsp->nsp);
1237 		__CTRACE(__CTRACE_REFRESH, "makech: csp=(%x,%x,%x,%x,%p)\n",
1238 			csp->ch, csp->attr, win->bch, win->battr, csp->nsp);
1239 #endif
1240 #endif /* DEBUG */
1241 		if (!(wlp->flags & __ISFORCED) &&
1242 #ifdef HAVE_WCHAR
1243 		    ((nsp->attr & __WCWIDTH) != __WCWIDTH) &&
1244 #endif
1245 		    celleq(nsp, csp))
1246 		{
1247 			if (wx <= lch) {
1248 				while (wx <= lch && celleq(nsp, csp)) {
1249 					nsp++;
1250 					if (!_cursesi_screen->curwin)
1251 						++csp;
1252 					++wx;
1253 				}
1254 				continue;
1255 			}
1256 			break;
1257 		}
1258 
1259 		domvcur(win, _cursesi_screen->ly, _cursesi_screen->lx, wy, wx);
1260 
1261 #ifdef DEBUG
1262 		__CTRACE(__CTRACE_REFRESH, "makech: 1: wx = %d, ly= %d, "
1263 		    "lx = %d, newy = %d, newx = %d\n",
1264 		    wx, _cursesi_screen->ly, _cursesi_screen->lx, wy, wx);
1265 #endif
1266 		_cursesi_screen->ly = wy;
1267 		_cursesi_screen->lx = wx;
1268 		while (wx <= lch &&
1269 		       ((wlp->flags & __ISFORCED) || !celleq(nsp, csp)))
1270 		{
1271 #ifndef HAVE_WCHAR
1272 			if (ce != NULL && wx >= nlsp
1273 			    && nsp->ch == ' ' && nsp->attr == lspc)
1274 #else
1275 			if (ce != NULL && wx >= nlsp
1276 			    && nsp->ch == (wchar_t)btowc((int)' ') /* XXX */
1277 			    && (nsp->attr & WA_ATTRIBUTES) == lspc)
1278 #endif
1279 			{
1280 				/* Check for clear to end-of-line. */
1281 				cep = &curscr->alines[wy]->line[win->maxx - 1];
1282 #ifndef HAVE_WCHAR
1283 				while (cep->ch == ' ' && cep->attr == lspc) /* XXX */
1284 #else
1285 				while (cep->ch == (wchar_t)btowc((int)' ')
1286 				       && (cep->attr & WA_ATTRIBUTES) == lspc)
1287 #endif /* HAVE_WCHAR */
1288 					if (cep-- <= csp)
1289 						break;
1290 				if (cep > (curscr->alines[wy]->line + win->begx * __LDATASIZE))
1291 					clsp = cep - curscr->alines[wy]->line -
1292 					win->begx * __LDATASIZE;
1293 				else
1294 					clsp = 0;
1295 #ifdef DEBUG
1296 				__CTRACE(__CTRACE_REFRESH,
1297 				    "makech: clsp = %zu, nlsp = %zu\n",
1298 				    clsp, nlsp);
1299 				__CTRACE(__CTRACE_REFRESH,
1300 				    "makech: line = %p, cep = %p, begx = %u\n",
1301 				    curscr->alines[wy]->line, cep, win->begx);
1302 #endif
1303 				if (((clsp - nlsp >= strlen(ce) &&
1304 				    clsp < win->maxx * __LDATASIZE) ||
1305 				    wy == win->maxy - 1) &&
1306 				    (!(lspc & __COLOR) ||
1307 				    ((lspc & __COLOR) && back_color_erase)))
1308 				{
1309 					__unsetattr(0);
1310 					if (__using_color &&
1311 					    ((lspc & __COLOR) !=
1312 					    (curscr->wattr & __COLOR)))
1313 						__set_color(curscr, lspc &
1314 						    __COLOR);
1315 					tputs(ce, 0, __cputchar);
1316 					_cursesi_screen->lx = wx + win->begx;
1317 					while (wx++ <= clsp) {
1318 						csp->attr = lspc;
1319 #ifndef HAVE_WCHAR
1320 						csp->ch = ' '; /* XXX */
1321 #else
1322 						csp->ch = (wchar_t)btowc((int)' ');
1323 						SET_WCOL( *csp, 1 );
1324 #endif /* HAVE_WCHAR */
1325 						csp++;
1326 					}
1327 					return OK;
1328 				}
1329 				ce = NULL;
1330 			}
1331 
1332 #ifdef HAVE_WCHAR
1333 			chw = WCOL(*nsp);
1334 			if (chw < 0)
1335 				chw = 0; /* match putch() */
1336 #else
1337 			chw = 1;
1338 #endif /* HAVE_WCHAR */
1339 			if (wx + chw >= win->maxx &&
1340 			    wy == win->maxy - 1 && !_cursesi_screen->curwin)
1341 			{
1342 				if (win->flags & __ENDLINE)
1343 					__unsetattr(1);
1344 				if (!(win->flags & __SCROLLWIN)) {
1345 					int e;
1346 
1347 					if (win->flags & __SCROLLOK)
1348 						e = putch(nsp, csp, wy, wx);
1349 					else
1350 						e = putchbr(nsp, csp,
1351 						    nsp == fsp ? NULL : nsp - 1,
1352 						    wy, wx);
1353 					if (e == ERR)
1354 						return ERR;
1355 				}
1356 				if (wx + chw < curscr->maxx) {
1357 					domvcur(win,
1358 					    _cursesi_screen->ly, wx,
1359 					    (int)(win->maxy - 1),
1360 					    (int)(win->maxx - 1));
1361 				}
1362 				_cursesi_screen->ly = win->maxy - 1;
1363 				_cursesi_screen->lx = win->maxx - 1;
1364 				return OK;
1365 			}
1366 			if (wx + chw < win->maxx || wy < win->maxy - 1 ||
1367 			    !(win->flags & __SCROLLWIN))
1368 			{
1369 				if (putch(nsp, csp, wy, wx) == ERR)
1370 					return ERR;
1371 				csp++;
1372 			} else {
1373 				putattr(nsp);
1374 				putattr_out(nsp);
1375 			}
1376 			wx += chw;
1377 			nsp++;
1378 #ifdef DEBUG
1379 			__CTRACE(__CTRACE_REFRESH,
1380 			    "makech: 2: wx = %d, lx = %d\n",
1381 			    wx, _cursesi_screen->lx);
1382 #endif
1383 		}
1384 		if (_cursesi_screen->lx == wx)	/* If no change. */
1385 			break;
1386 		_cursesi_screen->lx = wx;
1387 		if (_cursesi_screen->lx >= COLS && auto_right_margin)
1388 			_cursesi_screen->lx = COLS - 1;
1389 		else
1390 			if (wx >= win->maxx) {
1391 				domvcur(win,
1392 					_cursesi_screen->ly,
1393 					_cursesi_screen->lx,
1394 					_cursesi_screen->ly,
1395 					(int)(win->maxx - 1));
1396 				_cursesi_screen->lx = win->maxx - 1;
1397 			}
1398 #ifdef DEBUG
1399 		__CTRACE(__CTRACE_REFRESH, "makech: 3: wx = %d, lx = %d\n",
1400 		    wx, _cursesi_screen->lx);
1401 #endif
1402 	}
1403 #ifdef DEBUG
1404 #if HAVE_WCHAR
1405 	{
1406 		int x;
1407 		__LDATA *lp, *vlp;
1408 
1409 		__CTRACE(__CTRACE_REFRESH,
1410 		    "makech-after: curscr(%p)-__virtscr(%p)\n",
1411 		    curscr, __virtscr );
1412 		for (x = 0; x < curscr->maxx; x++) {
1413 			lp = &curscr->alines[wy]->line[x];
1414 			vlp = &__virtscr->alines[wy]->line[x];
1415 			__CTRACE(__CTRACE_REFRESH,
1416 			    "[%d,%d](%x,%x,%x,%x,%p)-"
1417 			    "(%x,%x,%x,%x,%p)\n",
1418 			    wy, x, lp->ch, lp->attr,
1419 			    win->bch, win->battr, lp->nsp,
1420 			    vlp->ch, vlp->attr,
1421 			    win->bch, win->battr, vlp->nsp);
1422 		}
1423 	}
1424 #endif /* HAVE_WCHAR */
1425 #endif /* DEBUG */
1426 
1427 	return OK;
1428 }
1429 
1430 /*
1431  * domvcur --
1432  *	Do a mvcur, leaving attributes if necessary.
1433  */
1434 static void
1435 domvcur(WINDOW *win, int oy, int ox, int ny, int nx)
1436 {
1437 
1438 #ifdef DEBUG
1439 	__CTRACE(__CTRACE_REFRESH, "domvcur: (%d,%d)=>(%d,%d) win %p\n",
1440 	    oy, ox, ny, nx, win );
1441 #endif /* DEBUG */
1442 
1443 	__unsetattr(1);
1444 
1445 	/* Don't move the cursor unless we need to. */
1446 	if (oy == ny && ox == nx) {
1447 		/* Check EOL. */
1448 		if (!(win->alines[oy]->flags & __ISPASTEOL))
1449 			return;
1450 	}
1451 
1452 	/* Clear EOL flags. */
1453 	win->alines[oy]->flags &= ~__ISPASTEOL;
1454 	win->alines[ny]->flags &= ~__ISPASTEOL;
1455 
1456 	__mvcur(oy, ox, ny, nx, 1);
1457 }
1458 
1459 /*
1460  * Quickch() attempts to detect a pattern in the change of the window
1461  * in order to optimize the change, e.g., scroll n lines as opposed to
1462  * repainting the screen line by line.
1463  */
1464 
1465 static __LDATA buf[128];
1466 static  unsigned int last_hash;
1467 static  size_t last_hash_len;
1468 #define BLANKSIZE (sizeof(buf) / sizeof(buf[0]))
1469 
1470 static void
1471 quickch(void)
1472 {
1473 #define THRESH		(int) __virtscr->maxy / 4
1474 
1475 	__LINE *clp, *tmp1, *tmp2;
1476 	int	bsize, curs, curw, starts, startw, i, j;
1477 	int	n, target, cur_period, bot, top, sc_region;
1478 	unsigned int	blank_hash;
1479 	attr_t	bcolor;
1480 
1481 #ifdef __GNUC__
1482 	curs = curw = starts = startw = 0;	/* XXX gcc -Wuninitialized */
1483 #endif
1484 	/*
1485 	 * Find how many lines from the top of the screen are unchanged.
1486 	 */
1487 	for (top = 0; top < __virtscr->maxy; top++) {
1488 		if (__virtscr->alines[top]->flags & __ISDIRTY &&
1489 		    (__virtscr->alines[top]->hash != curscr->alines[top]->hash ||
1490 		     !lineeq(__virtscr->alines[top]->line,
1491 			     curscr->alines[top]->line,
1492 			     (size_t) __virtscr->maxx)))
1493 			break;
1494 		else
1495 			__virtscr->alines[top]->flags &= ~__ISDIRTY;
1496 	}
1497 	/*
1498 	 * Find how many lines from bottom of screen are unchanged.
1499 	 */
1500 	for (bot = __virtscr->maxy - 1; bot >= 0; bot--) {
1501 		if (__virtscr->alines[bot]->flags & __ISDIRTY &&
1502 		    (__virtscr->alines[bot]->hash != curscr->alines[bot]->hash ||
1503 		     !lineeq(__virtscr->alines[bot]->line,
1504 			     curscr->alines[bot]->line,
1505 			     (size_t) __virtscr->maxx)))
1506 			break;
1507 		else
1508 			__virtscr->alines[bot]->flags &= ~__ISDIRTY;
1509 	}
1510 
1511 	/*
1512 	 * Work round an xterm bug where inserting lines causes all the
1513 	 * inserted lines to be covered with the background colour we
1514 	 * set on the first line (even if we unset it for subsequent
1515 	 * lines).
1516 	 */
1517 	bcolor = __virtscr->alines[min(top,
1518 	    __virtscr->maxy - 1)]->line[0].attr & __COLOR;
1519 	for (i = top + 1, j = 0; i < bot; i++) {
1520 		if ((__virtscr->alines[i]->line[0].attr & __COLOR) != bcolor) {
1521 			bcolor = __virtscr->alines[i]->line[__virtscr->maxx].
1522 			    attr & __COLOR;
1523 			j = i - top;
1524 		} else
1525 			break;
1526 	}
1527 	top += j;
1528 
1529 #ifdef NO_JERKINESS
1530 	/*
1531 	 * If we have a bottom unchanged region return.  Scrolling the
1532 	 * bottom region up and then back down causes a screen jitter.
1533 	 * This will increase the number of characters sent to the screen
1534 	 * but it looks better.
1535 	 */
1536 	if (bot < __virtscr->maxy - 1)
1537 		return;
1538 #endif				/* NO_JERKINESS */
1539 
1540 	/*
1541 	 * Search for the largest block of text not changed.
1542 	 * Invariants of the loop:
1543 	 * - Startw is the index of the beginning of the examined block in
1544 	 *   __virtscr.
1545 	 * - Starts is the index of the beginning of the examined block in
1546 	 *   curscr.
1547 	 * - Curw is the index of one past the end of the exmined block in
1548 	 *   __virtscr.
1549 	 * - Curs is the index of one past the end of the exmined block in
1550 	 *   curscr.
1551 	 * - bsize is the current size of the examined block.
1552 	*/
1553 
1554 	for (bsize = bot - top; bsize >= THRESH; bsize--) {
1555 		for (startw = top; startw <= bot - bsize; startw++)
1556 			for (starts = top; starts <= bot - bsize; starts++) {
1557 				for (curw = startw, curs = starts;
1558 				    curs < starts + bsize; curw++, curs++)
1559 					if (__virtscr->alines[curw]->hash !=
1560 					    curscr->alines[curs]->hash)
1561 						break;
1562 				if (curs != starts + bsize)
1563 					continue;
1564 				for (curw = startw, curs = starts;
1565 					curs < starts + bsize; curw++, curs++)
1566 					if (!lineeq(__virtscr->alines[curw]->line,
1567 						    curscr->alines[curs]->line,
1568 						    (size_t) __virtscr->maxx))
1569 						break;
1570 				if (curs == starts + bsize)
1571 					goto done;
1572 			}
1573 	}
1574 done:
1575 
1576 	/* Did not find anything */
1577 	if (bsize < THRESH)
1578 		return;
1579 
1580 #ifdef DEBUG
1581 	__CTRACE(__CTRACE_REFRESH, "quickch:bsize=%d, starts=%d, startw=%d, "
1582 	    "curw=%d, curs=%d, top=%d, bot=%d\n",
1583 	    bsize, starts, startw, curw, curs, top, bot);
1584 #endif
1585 
1586 	/*
1587 	 * Make sure that there is no overlap between the bottom and top
1588 	 * regions and the middle scrolled block.
1589 	 */
1590 	if (bot < curs)
1591 		bot = curs - 1;
1592 	if (top > starts)
1593 		top = starts;
1594 
1595 	n = startw - starts;
1596 
1597 #ifdef DEBUG
1598 	__CTRACE(__CTRACE_REFRESH, "#####################################\n");
1599 	for (i = 0; i < curscr->maxy; i++) {
1600 		__CTRACE(__CTRACE_REFRESH, "C: %d:", i);
1601 		__CTRACE(__CTRACE_REFRESH, " 0x%x \n", curscr->alines[i]->hash);
1602 		for (j = 0; j < curscr->maxx; j++)
1603 			__CTRACE(__CTRACE_REFRESH, "%c",
1604 			    curscr->alines[i]->line[j].ch);
1605 		__CTRACE(__CTRACE_REFRESH, "\n");
1606 		__CTRACE(__CTRACE_REFRESH, " attr:");
1607 		for (j = 0; j < curscr->maxx; j++)
1608 			__CTRACE(__CTRACE_REFRESH, " %x",
1609 			    curscr->alines[i]->line[j].attr);
1610 		__CTRACE(__CTRACE_REFRESH, "\n");
1611 		__CTRACE(__CTRACE_REFRESH, "W: %d:", i);
1612 		__CTRACE(__CTRACE_REFRESH, " 0x%x \n",
1613 		    __virtscr->alines[i]->hash);
1614 		__CTRACE(__CTRACE_REFRESH, " 0x%x ",
1615 		    __virtscr->alines[i]->flags);
1616 		for (j = 0; j < __virtscr->maxx; j++)
1617 			__CTRACE(__CTRACE_REFRESH, "%c",
1618 			    __virtscr->alines[i]->line[j].ch);
1619 		__CTRACE(__CTRACE_REFRESH, "\n");
1620 		__CTRACE(__CTRACE_REFRESH, " attr:");
1621 		for (j = 0; j < __virtscr->maxx; j++)
1622 			__CTRACE(__CTRACE_REFRESH, " %x",
1623 			    __virtscr->alines[i]->line[j].attr);
1624 		__CTRACE(__CTRACE_REFRESH, "\n");
1625 	}
1626 #endif
1627 
1628 #ifndef HAVE_WCHAR
1629 	if (buf[0].ch != ' ') {
1630 		for (i = 0; i < BLANKSIZE; i++) {
1631 			buf[i].ch = ' ';
1632 			buf[i].attr = 0;
1633 		}
1634 	}
1635 #else
1636 	if (buf[0].ch != (wchar_t)btowc((int)curscr->bch )) {
1637 		for (i = 0; i < BLANKSIZE; i++) {
1638 			buf[i].ch = (wchar_t)btowc((int)curscr->bch);
1639 			if (_cursesi_copy_nsp(curscr->bnsp, &buf[i]) == ERR)
1640 				return;
1641 			buf[i].attr = 0;
1642 			SET_WCOL(buf[i], 1);
1643 		}
1644 	}
1645 #endif /* HAVE_WCHAR */
1646 
1647 	if (__virtscr->maxx != last_hash_len) {
1648 		blank_hash = 0;
1649 		for (i = __virtscr->maxx; i > BLANKSIZE; i -= BLANKSIZE) {
1650 			blank_hash = __hash_more(buf, sizeof(buf), blank_hash);
1651 		}
1652 		blank_hash = __hash_more((char *)(void *)buf,
1653 		    i * sizeof(buf[0]), blank_hash);
1654 		/* cache result in static data - screen width doesn't change often */
1655 		last_hash_len = __virtscr->maxx;
1656 		last_hash = blank_hash;
1657 	} else
1658 		blank_hash = last_hash;
1659 
1660 	/*
1661 	 * Perform the rotation to maintain the consistency of curscr.
1662 	 * This is hairy since we are doing an *in place* rotation.
1663 	 * Invariants of the loop:
1664 	 * - I is the index of the current line.
1665 	 * - Target is the index of the target of line i.
1666 	 * - Tmp1 points to current line (i).
1667 	 * - Tmp2 and points to target line (target);
1668 	 * - Cur_period is the index of the end of the current period.
1669 	 *   (see below).
1670 	 *
1671 	 * There are 2 major issues here that make this rotation non-trivial:
1672 	 * 1.  Scrolling in a scrolling region bounded by the top
1673 	 *     and bottom regions determined (whose size is sc_region).
1674 	 * 2.  As a result of the use of the mod function, there may be a
1675 	 *     period introduced, i.e., 2 maps to 4, 4 to 6, n-2 to 0, and
1676 	 *     0 to 2, which then causes all odd lines not to be rotated.
1677 	 *     To remedy this, an index of the end ( = beginning) of the
1678 	 *     current 'period' is kept, cur_period, and when it is reached,
1679 	 *     the next period is started from cur_period + 1 which is
1680 	 *     guaranteed not to have been reached since that would mean that
1681 	 *     all records would have been reached. (think about it...).
1682 	 *
1683 	 * Lines in the rotation can have 3 attributes which are marked on the
1684 	 * line so that curscr is consistent with the visual screen.
1685 	 * 1.  Not dirty -- lines inside the scrolled block, top region or
1686 	 *                  bottom region.
1687 	 * 2.  Blank lines -- lines in the differential of the scrolling
1688 	 *		      region adjacent to top and bot regions
1689 	 *                    depending on scrolling direction.
1690 	 * 3.  Dirty line -- all other lines are marked dirty.
1691 	 */
1692 	sc_region = bot - top + 1;
1693 	i = top;
1694 	tmp1 = curscr->alines[top];
1695 	cur_period = top;
1696 	for (j = top; j <= bot; j++) {
1697 		target = (i - top + n + sc_region) % sc_region + top;
1698 		tmp2 = curscr->alines[target];
1699 		curscr->alines[target] = tmp1;
1700 		/* Mark block as clean and blank out scrolled lines. */
1701 		clp = curscr->alines[target];
1702 #ifdef DEBUG
1703 		__CTRACE(__CTRACE_REFRESH,
1704 		    "quickch: n=%d startw=%d curw=%d i = %d target=%d ",
1705 		    n, startw, curw, i, target);
1706 #endif
1707 		if ((target >= startw && target < curw) || target < top
1708 		    || target > bot)
1709 		{
1710 #ifdef DEBUG
1711 			__CTRACE(__CTRACE_REFRESH, " notdirty\n");
1712 #endif
1713 			__virtscr->alines[target]->flags &= ~__ISDIRTY;
1714 		} else
1715 			if ((n > 0 && target >= top && target < top + n) ||
1716 			    (n < 0 && target <= bot && target > bot + n))
1717 			{
1718 				if (clp->hash != blank_hash ||
1719 				    !lineeq(clp->line, clp->line + 1,
1720 					    (__virtscr->maxx - 1)) ||
1721 				    !celleq(clp->line, buf))
1722 				{
1723 					for (i = __virtscr->maxx;
1724 					    i > BLANKSIZE;
1725 					    i -= BLANKSIZE) {
1726 						(void) memcpy(clp->line + i -
1727 						    BLANKSIZE, buf, sizeof(buf));
1728 					}
1729 					(void) memcpy(clp->line , buf, i *
1730 					    sizeof(buf[0]));
1731 #ifdef DEBUG
1732 					__CTRACE(__CTRACE_REFRESH,
1733 					    " blanked out: dirty\n");
1734 #endif
1735 					clp->hash = blank_hash;
1736 					__touchline(__virtscr, target, 0, (int) __virtscr->maxx - 1);
1737 				} else {
1738 #ifdef DEBUG
1739 					__CTRACE(__CTRACE_REFRESH,
1740 					    " -- blank line already: dirty\n");
1741 #endif
1742 					__touchline(__virtscr, target, 0, (int) __virtscr->maxx - 1);
1743 				}
1744 			} else {
1745 #ifdef DEBUG
1746 				__CTRACE(__CTRACE_REFRESH, " -- dirty\n");
1747 #endif
1748 				__touchline(__virtscr, target, 0, (int) __virtscr->maxx - 1);
1749 			}
1750 		if (target == cur_period) {
1751 			i = target + 1;
1752 			tmp1 = curscr->alines[i];
1753 			cur_period = i;
1754 		} else {
1755 			tmp1 = tmp2;
1756 			i = target;
1757 		}
1758 	}
1759 #ifdef DEBUG
1760 	__CTRACE(__CTRACE_REFRESH, "$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$\n");
1761 	for (i = 0; i < curscr->maxy; i++) {
1762 		__CTRACE(__CTRACE_REFRESH, "C: %d:", i);
1763 		for (j = 0; j < curscr->maxx; j++)
1764 			__CTRACE(__CTRACE_REFRESH, "%c",
1765 			    curscr->alines[i]->line[j].ch);
1766 		__CTRACE(__CTRACE_REFRESH, "\n");
1767 		__CTRACE(__CTRACE_REFRESH, "W: %d:", i);
1768 		for (j = 0; j < __virtscr->maxx; j++)
1769 			__CTRACE(__CTRACE_REFRESH, "%c",
1770 			    __virtscr->alines[i]->line[j].ch);
1771 		__CTRACE(__CTRACE_REFRESH, "\n");
1772 	}
1773 #endif
1774 	if (n != 0)
1775 		scrolln(starts, startw, curs, bot, top);
1776 }
1777 
1778 /*
1779  * scrolln --
1780  *	Scroll n lines, where n is starts - startw.
1781  */
1782 static void /* ARGSUSED */
1783 scrolln(int starts, int startw, int curs, int bot, int top)
1784 {
1785 	int	i, oy, ox, n;
1786 
1787 	oy = curscr->cury;
1788 	ox = curscr->curx;
1789 	n = starts - startw;
1790 
1791 	/*
1792 	 * XXX
1793 	 * The initial tests that set __noqch don't let us reach here unless
1794 	 * we have either cs + ho + SF/sf/SR/sr, or AL + DL.  SF/sf and SR/sr
1795 	 * scrolling can only shift the entire scrolling region, not just a
1796 	 * part of it, which means that the quickch() routine is going to be
1797 	 * sadly disappointed in us if we don't have cs as well.
1798 	 *
1799 	 * If cs, ho and SF/sf are set, can use the scrolling region.  Because
1800 	 * the cursor position after cs is undefined, we need ho which gives us
1801 	 * the ability to move to somewhere without knowledge of the current
1802 	 * location of the cursor.  Still call __mvcur() anyway, to update its
1803 	 * idea of where the cursor is.
1804 	 *
1805 	 * When the scrolling region has been set, the cursor has to be at the
1806 	 * last line of the region to make the scroll happen.
1807 	 *
1808 	 * Doing SF/SR or AL/DL appears faster on the screen than either sf/sr
1809 	 * or AL/DL, and, some terminals have AL/DL, sf/sr, and cs, but not
1810 	 * SF/SR.  So, if we're scrolling almost all of the screen, try and use
1811 	 * AL/DL, otherwise use the scrolling region.  The "almost all" is a
1812 	 * shameless hack for vi.
1813 	 */
1814 	if (n > 0) {
1815 		if (change_scroll_region != NULL && cursor_home != NULL &&
1816 		    (parm_index != NULL ||
1817 		    ((parm_insert_line == NULL || parm_delete_line == NULL ||
1818 		    top > 3 || bot + 3 < __virtscr->maxy) &&
1819 		    scroll_forward != NULL)))
1820 		{
1821 			tputs(tiparm(change_scroll_region, top, bot),
1822 			    0, __cputchar);
1823 			__mvcur(oy, ox, 0, 0, 1);
1824 			tputs(cursor_home, 0, __cputchar);
1825 			__mvcur(0, 0, bot, 0, 1);
1826 			if (parm_index != NULL)
1827 				tputs(tiparm(parm_index, n),
1828 				    0, __cputchar);
1829 			else
1830 				for (i = 0; i < n; i++)
1831 					tputs(scroll_forward, 0, __cputchar);
1832 			tputs(tiparm(change_scroll_region,
1833 			    0, (int)__virtscr->maxy - 1), 0, __cputchar);
1834 			__mvcur(bot, 0, 0, 0, 1);
1835 			tputs(cursor_home, 0, __cputchar);
1836 			__mvcur(0, 0, oy, ox, 1);
1837 			return;
1838 		}
1839 
1840 		/* Scroll up the block. */
1841 		if (parm_index != NULL && top == 0) {
1842 			__mvcur(oy, ox, bot, 0, 1);
1843 			tputs(tiparm(parm_index, n), 0, __cputchar);
1844 		} else
1845 			if (parm_delete_line != NULL) {
1846 				__mvcur(oy, ox, top, 0, 1);
1847 				tputs(tiparm(parm_delete_line, n),
1848 				    0, __cputchar);
1849 			} else
1850 				if (delete_line != NULL) {
1851 					__mvcur(oy, ox, top, 0, 1);
1852 					for (i = 0; i < n; i++)
1853 						tputs(delete_line, 0,
1854 						    __cputchar);
1855 				} else
1856 					if (scroll_forward != NULL && top == 0) {
1857 						__mvcur(oy, ox, bot, 0, 1);
1858 						for (i = 0; i < n; i++)
1859 							tputs(scroll_forward, 0,
1860 							    __cputchar);
1861 					} else
1862 						abort();
1863 
1864 		/* Push down the bottom region. */
1865 		__mvcur(top, 0, bot - n + 1, 0, 1);
1866 		if (parm_insert_line != NULL)
1867 			tputs(tiparm(parm_insert_line, n), 0, __cputchar);
1868 		else {
1869 			if (insert_line != NULL) {
1870 				for (i = 0; i < n; i++)
1871 					tputs(insert_line, 0, __cputchar);
1872 			} else
1873 				abort();
1874 		}
1875 		__mvcur(bot - n + 1, 0, oy, ox, 1);
1876 	} else {
1877 		/*
1878 		 * !!!
1879 		 * n < 0
1880 		 *
1881 		 * If cs, ho and SR/sr are set, can use the scrolling region.
1882 		 * See the above comments for details.
1883 		 */
1884 		if (change_scroll_region != NULL && cursor_home != NULL &&
1885 		    (parm_rindex != NULL ||
1886 		    ((parm_insert_line == NULL || parm_delete_line == NULL ||
1887 		    top > 3 ||
1888 		    bot + 3 < __virtscr->maxy) && scroll_reverse != NULL)))
1889 		{
1890 			tputs(tiparm(change_scroll_region, top, bot),
1891 			    0, __cputchar);
1892 			__mvcur(oy, ox, 0, 0, 1);
1893 			tputs(cursor_home, 0, __cputchar);
1894 			__mvcur(0, 0, top, 0, 1);
1895 
1896 			if (parm_rindex != NULL)
1897 				tputs(tiparm(parm_rindex, -n),
1898 				    0, __cputchar);
1899 			else
1900 				for (i = n; i < 0; i++)
1901 					tputs(scroll_reverse, 0, __cputchar);
1902 			tputs(tiparm(change_scroll_region,
1903 			    0, (int) __virtscr->maxy - 1), 0, __cputchar);
1904 			__mvcur(top, 0, 0, 0, 1);
1905 			tputs(cursor_home, 0, __cputchar);
1906 			__mvcur(0, 0, oy, ox, 1);
1907 			return;
1908 		}
1909 
1910 		/* Preserve the bottom lines. */
1911 		__mvcur(oy, ox, bot + n + 1, 0, 1);
1912 		if (parm_rindex != NULL && bot == __virtscr->maxy)
1913 			tputs(tiparm(parm_rindex, -n), 0, __cputchar);
1914 		else {
1915 			if (parm_delete_line != NULL)
1916 				tputs(tiparm(parm_delete_line, -n),
1917 				    0, __cputchar);
1918 			else {
1919 				if (delete_line != NULL)
1920 					for (i = n; i < 0; i++)
1921 						tputs(delete_line,
1922 						    0, __cputchar);
1923 				else {
1924 					if (scroll_reverse != NULL &&
1925 					    bot == __virtscr->maxy)
1926 						for (i = n; i < 0; i++)
1927 							tputs(scroll_reverse, 0,
1928 							    __cputchar);
1929 					else
1930 						abort();
1931 				}
1932 			}
1933 		}
1934 		/* Scroll the block down. */
1935 		__mvcur(bot + n + 1, 0, top, 0, 1);
1936 		if (parm_insert_line != NULL)
1937 			tputs(tiparm(parm_insert_line, -n), 0, __cputchar);
1938 		else
1939 			if (insert_line != NULL)
1940 				for (i = n; i < 0; i++)
1941 					tputs(insert_line, 0, __cputchar);
1942 			else
1943 				abort();
1944 		__mvcur(top, 0, oy, ox, 1);
1945 	}
1946 }
1947 
1948 /*
1949  * __unsetattr --
1950  *	Unset attributes on curscr.  Leave standout, attribute and colour
1951  *	modes if necessary (!ms).  Always leave altcharset (xterm at least
1952  *	ignores a cursor move if we don't).
1953  */
1954 void /* ARGSUSED */
1955 __unsetattr(int checkms)
1956 {
1957 	int	isms;
1958 
1959 	if (checkms) {
1960 		if (!move_standout_mode)
1961 			isms = 1;
1962 		else
1963 			isms = 0;
1964 	} else
1965 		isms = 1;
1966 #ifdef DEBUG
1967 	__CTRACE(__CTRACE_REFRESH,
1968 	    "__unsetattr: checkms = %d, ms = %s, wattr = %08x\n",
1969 	    checkms, move_standout_mode ? "TRUE" : "FALSE", curscr->wattr);
1970 #endif
1971 
1972 	/*
1973 	 * Don't leave the screen in standout mode (check against ms).  Check
1974 	 * to see if we also turn off underscore, attributes and colour.
1975 	 */
1976 	if (curscr->wattr & __STANDOUT && isms) {
1977 		tputs(exit_standout_mode, 0, __cputchar);
1978 		curscr->wattr &= __mask_se;
1979 	}
1980 	/*
1981 	 * Don't leave the screen in underscore mode (check against ms).
1982 	 * Check to see if we also turn off attributes.  Assume that we
1983 	 * also turn off colour.
1984 	 */
1985 	if (curscr->wattr & __UNDERSCORE && isms) {
1986 		tputs(exit_underline_mode, 0, __cputchar);
1987 		curscr->wattr &= __mask_ue;
1988 	}
1989 	/*
1990 	 * Don't leave the screen with attributes set (check against ms).
1991 	 * Assume that also turn off colour.
1992 	 */
1993 	if (curscr->wattr & __TERMATTR && isms) {
1994 		tputs(exit_attribute_mode, 0, __cputchar);
1995 		curscr->wattr &= __mask_me;
1996 	}
1997 	/* Don't leave the screen with altcharset set (don't check ms). */
1998 	if (curscr->wattr & __ALTCHARSET) {
1999 		tputs(exit_alt_charset_mode, 0, __cputchar);
2000 		curscr->wattr &= ~__ALTCHARSET;
2001 	}
2002 	/* Don't leave the screen with colour set (check against ms). */
2003 	if (__using_color && isms)
2004 		__unset_color(curscr);
2005 }
2006 
2007 #ifdef HAVE_WCHAR
2008 /* compare two cells on screen, must have the same forground/background,
2009  * and the same sequence of non-spacing characters */
2010 static int
2011 celleq(__LDATA *x, __LDATA *y)
2012 {
2013 	nschar_t *xnp = x->nsp, *ynp = y->nsp;
2014 	int ret = ( x->ch == y->ch ) && ( x->attr == y->attr );
2015 
2016 	if (!ret)
2017 		return 0;
2018 	if (!xnp && !ynp)
2019 		return 1;
2020 	if ((xnp && !ynp) || (!xnp && ynp))
2021 		return 0;
2022 
2023 	while (xnp && ynp) {
2024 		if (xnp->ch != ynp->ch)
2025 			return 0;
2026 		xnp = xnp->next;
2027 		ynp = ynp->next;
2028 	}
2029 	return !xnp && !ynp;
2030 }
2031 
2032 /* compare two line segments */
2033 static int
2034 lineeq(__LDATA *xl, __LDATA *yl, size_t len)
2035 {
2036 	int i = 0;
2037 	__LDATA *xp = xl, *yp = yl;
2038 
2039 	for (i = 0; i < len; i++, xp++, yp++) {
2040 		if (!celleq(xp, yp))
2041 			return 0;
2042 	}
2043 	return 1;
2044 }
2045 
2046 /*
2047  * Output the non-spacing characters associated with the given character
2048  * cell to the screen.
2049  */
2050 
2051 void
2052 __cursesi_putnsp(nschar_t *nsp, const int wy, const int wx)
2053 {
2054 	nschar_t *p;
2055 
2056 	/* this shuts up gcc warnings about wx and wy not being used */
2057 	if (wx > wy) {
2058 	}
2059 
2060 	p = nsp;
2061 	while (p != NULL) {
2062 		__cputwchar((int)p->ch);
2063 #ifdef DEBUG
2064 		__CTRACE(__CTRACE_REFRESH,
2065 		       "_cursesi_putnsp: (%d,%d) non-spacing putwchar(0x%x)\n",
2066 			 wy, wx - 1, p->ch);
2067 #endif
2068 		p = p->next;
2069 	}
2070 }
2071 
2072 #endif /* HAVE_WCHAR */
2073