xref: /netbsd-src/lib/libcurses/refresh.c (revision 8e6f7afb5bba2c07fd084c08249718961dfbc1d1)
1 /*	$NetBSD: refresh.c,v 1.43 2001/12/02 09:14:22 blymn 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. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by the University of
18  *	California, Berkeley and its contributors.
19  * 4. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #include <sys/cdefs.h>
37 #ifndef lint
38 #if 0
39 static char sccsid[] = "@(#)refresh.c	8.7 (Berkeley) 8/13/94";
40 #else
41 __RCSID("$NetBSD: refresh.c,v 1.43 2001/12/02 09:14:22 blymn Exp $");
42 #endif
43 #endif				/* not lint */
44 
45 #include <stdlib.h>
46 #include <string.h>
47 
48 #include "curses.h"
49 #include "curses_private.h"
50 
51 static void	domvcur __P((int, int, int, int));
52 static int	makech __P((int));
53 static void	quickch __P((void));
54 static void	scrolln __P((int, int, int, int, int));
55 
56 #ifndef _CURSES_USE_MACROS
57 
58 /*
59  * refresh --
60  *	Make the current screen look like "stdscr" over the area covered by
61  *	stdscr.
62  */
63 int
64 refresh(void)
65 {
66 	return wrefresh(stdscr);
67 }
68 
69 #endif
70 
71 /*
72  * wnoutrefresh --
73  *	Add the contents of "win" to the virtual window.
74  */
75 int
76 wnoutrefresh(WINDOW *win)
77 {
78 	short	wy, wx, x_off;
79 	__LINE	*wlp, *vlp;
80 
81 #ifdef DEBUG
82 	__CTRACE("wnoutrefresh: win %0.2o, flags 0x%08x\n", win, win->flags);
83 #endif
84 
85 	if (_cursesi_screen->curwin)
86 		return(OK);
87 	__virtscr->cury = win->cury + win->begy;
88 	__virtscr->curx = win->curx + win->begx;
89 
90 	/* Copy the window flags from "win" to "__virtscr" */
91 	if (win->flags & __CLEAROK) {
92 		if (win->flags & __FULLWIN)
93 			__virtscr->flags |= __CLEAROK;
94 		win->flags &= ~__CLEAROK;
95 	}
96 	__virtscr->flags &= ~__LEAVEOK;
97 	__virtscr->flags |= win->flags;
98 
99 	for (wy = 0; wy < win->maxy && wy < __virtscr->maxy - win->begy; wy++) {
100 		wlp = win->lines[wy];
101 #ifdef DEBUG
102 		__CTRACE("wnoutrefresh: wy %d\tf: %d\tl:%d\tflags %x\n", wy,
103 		    *wlp->firstchp, *wlp->lastchp, wlp->flags);
104 #endif
105 		if ((wlp->flags & __ISDIRTY) == 0)
106 			continue;
107 		vlp = __virtscr->lines[wy + win->begy];
108 
109 		if (*wlp->firstchp < win->maxx + win->ch_off &&
110 		    *wlp->lastchp >= win->ch_off) {
111 			/* Copy line from "win" to "__virtscr". */
112 			for (wx = 0, x_off = win->begx; wx < win->maxx &&
113 			    x_off < __virtscr->maxx; wx++, x_off++) {
114 				vlp->line[x_off].attr = wlp->line[wx].attr;
115 				if (wlp->line[wx].attr & __COLOR)
116 					vlp->line[x_off].attr |=
117 					    wlp->line[wx].battr & ~__COLOR;
118 				else
119 					vlp->line[x_off].attr |=
120 					    wlp->line[wx].battr;
121 				if (wlp->line[wx].ch == ' ' &&
122 				    wlp->line[wx].bch != ' ')
123 					vlp->line[x_off].ch
124 					    = wlp->line[wx].bch;
125 				else
126 					vlp->line[x_off].ch
127 					    = wlp->line[wx].ch;
128 			}
129 
130 			/* Set flags on "__virtscr" and unset on "win". */
131 			if (wlp->flags & __ISPASTEOL)
132 				vlp->flags |= __ISPASTEOL;
133 			else
134 				vlp->flags &= ~__ISPASTEOL;
135 			if (wlp->flags & __ISDIRTY)
136 				vlp->flags |= __ISDIRTY;
137 
138 #ifdef DEBUG
139 			__CTRACE("win: firstch = %d, lastch = %d\n",
140 			    *wlp->firstchp, *wlp->lastchp);
141 #endif
142 			/* Set change pointers on "__virtscr". */
143 			if (*vlp->firstchp >
144 			    *wlp->firstchp + win->begx - win->ch_off)
145 				*vlp->firstchp =
146 				    *wlp->firstchp + win->begx - win->ch_off;
147 			if (*vlp->lastchp <
148 			    *wlp->lastchp + win->begx - win->ch_off)
149 				*vlp->lastchp =
150 				    *wlp->lastchp + win->begx - win->ch_off;
151 #ifdef DEBUG
152 			__CTRACE("__virtscr: firstch = %d, lastch = %d\n",
153 			    *vlp->firstchp, *vlp->lastchp);
154 #endif
155 
156 			/* Set change pointers on "win". */
157 			if (*wlp->firstchp >= win->ch_off)
158 				*wlp->firstchp = win->maxx + win->ch_off;
159 			if (*wlp->lastchp < win->maxx + win->ch_off)
160 				*wlp->lastchp = win->ch_off;
161 			if (*wlp->lastchp < *wlp->firstchp) {
162 #ifdef DEBUG
163 				__CTRACE("wnoutrefresh: line %d notdirty\n",
164 				    wy);
165 #endif
166 				wlp->flags &= ~__ISDIRTY;
167 			}
168 		}
169 	}
170 
171 	return (OK);
172 }
173 
174 /*
175  * wrefresh --
176  *	Make the current screen look like "win" over the area coverd by
177  *	win.
178  */
179 int
180 wrefresh(WINDOW *win)
181 {
182 	int	retval;
183 
184 	_cursesi_screen->curwin = (win == curscr);
185 	if (!_cursesi_screen->curwin)
186 		retval = wnoutrefresh(win);
187 	else
188 		retval = OK;
189 	if (retval == OK) {
190 		retval = doupdate();
191 		if (!win->flags & __LEAVEOK) {
192 			win->cury = max(0, curscr->cury - win->begy);
193 			win->curx = max(0, curscr->curx - win->begx);
194 		}
195 	}
196 	_cursesi_screen->curwin = 0;
197 	return(retval);
198 }
199 
200 /*
201  * doupdate --
202  *	Make the current screen look like the virtual window "__virtscr".
203  */
204 int
205 doupdate(void)
206 {
207 	WINDOW	*win;
208 	__LINE	*wlp;
209 	short	 wy;
210 	int	 dnum;
211 
212 	/* Check if we need to restart ... */
213 	if (_cursesi_screen->endwin)
214 		__restartwin();
215 
216 	if (_cursesi_screen->curwin)
217 		win = curscr;
218 	else
219 		win = __virtscr;
220 
221 	/* Initialize loop parameters. */
222 	_cursesi_screen->ly = curscr->cury;
223 	_cursesi_screen->lx = curscr->curx;
224 	wy = 0;
225 
226 	if (!_cursesi_screen->curwin)
227 		for (wy = 0; wy < win->maxy; wy++) {
228 			wlp = win->lines[wy];
229 			if (wlp->flags & __ISDIRTY)
230 				wlp->hash = __hash((char *)(void *)wlp->line,
231 				    (int) (win->maxx * __LDATASIZE));
232 		}
233 
234 	if ((win->flags & __CLEAROK) || (curscr->flags & __CLEAROK) ||
235 	    _cursesi_screen->curwin) {
236 		if (curscr->wattr & __COLOR)
237 			__unsetattr(0);
238 		tputs(__tc_cl, 0, __cputchar);
239 		_cursesi_screen->ly = 0;
240 		_cursesi_screen->lx = 0;
241 		if (!_cursesi_screen->curwin) {
242 			curscr->flags &= ~__CLEAROK;
243 			curscr->cury = 0;
244 			curscr->curx = 0;
245 			werase(curscr);
246 		}
247 		__touchwin(win);
248 		win->flags &= ~__CLEAROK;
249 	}
250 	if (!__CA) {
251 		if (win->curx != 0)
252 			__cputchar('\n');
253 		if (!_cursesi_screen->curwin)
254 			werase(curscr);
255 	}
256 #ifdef DEBUG
257 	__CTRACE("doupdate: (%0.2o): curwin = %d\n", win,
258 		 _cursesi_screen->curwin);
259 	__CTRACE("doupdate: \tfirstch\tlastch\n");
260 #endif
261 
262 	if (!_cursesi_screen->curwin) {
263 		/*
264 		 * Invoke quickch() only if more than a quarter of the lines
265 		 * in the window are dirty.
266 		 */
267 		for (wy = 0, dnum = 0; wy < win->maxy; wy++)
268 			if (win->lines[wy]->flags & __ISDIRTY)
269 				dnum++;
270 		if (!__noqch && dnum > (int) win->maxy / 4)
271 			quickch();
272 	}
273 
274 #ifdef DEBUG
275 	{
276 		int	i, j;
277 
278 		__CTRACE("#####################################\n");
279 		for (i = 0; i < curscr->maxy; i++) {
280 			__CTRACE("C: %d:", i);
281 			__CTRACE(" 0x%x \n", curscr->lines[i]->hash);
282 			for (j = 0; j < curscr->maxx; j++)
283 				__CTRACE("%c", curscr->lines[i]->line[j].ch);
284 			__CTRACE("\n");
285 			__CTRACE(" attr:");
286 			for (j = 0; j < curscr->maxx; j++)
287 				__CTRACE(" %x",
288 					 curscr->lines[i]->line[j].attr);
289 			__CTRACE("\n");
290 			__CTRACE("W: %d:", i);
291 			__CTRACE(" 0x%x \n", win->lines[i]->hash);
292 			__CTRACE(" 0x%x ", win->lines[i]->flags);
293 			for (j = 0; j < win->maxx; j++)
294 				__CTRACE("%c", win->lines[i]->line[j].ch);
295 			__CTRACE("\n");
296 			__CTRACE(" attr:");
297 			for (j = 0; j < win->maxx; j++)
298 				__CTRACE(" %x",
299 				    win->lines[i]->line[j].attr);
300 			__CTRACE("\n");
301 		}
302 	}
303 #endif				/* DEBUG */
304 
305 	for (wy = 0; wy < win->maxy; wy++) {
306 		wlp = win->lines[wy];
307 /* XXX: remove this debug */
308 #ifdef DEBUG
309 		__CTRACE("doupdate: wy %d\tf: %d\tl:%d\tflags %x\n", wy,
310 		    *wlp->firstchp, *wlp->lastchp, wlp->flags);
311 #endif
312 		if (!_cursesi_screen->curwin)
313 			curscr->lines[wy]->hash = wlp->hash;
314 		if (wlp->flags & __ISDIRTY) {
315 			if (makech(wy) == ERR)
316 				return (ERR);
317 			else {
318 				if (*wlp->firstchp >= 0)
319 					*wlp->firstchp = win->maxx;
320 				if (*wlp->lastchp < win->maxx)
321 					*wlp->lastchp = 0;
322 				if (*wlp->lastchp < *wlp->firstchp) {
323 #ifdef DEBUG
324 					__CTRACE("doupdate: line %d notdirty\n", wy);
325 #endif
326 					wlp->flags &= ~__ISDIRTY;
327 				}
328 			}
329 
330 		}
331 #ifdef DEBUG
332 		__CTRACE("\t%d\t%d\n", *wlp->firstchp, *wlp->lastchp);
333 #endif
334 	}
335 
336 #ifdef DEBUG
337 	__CTRACE("doupdate: ly=%d, lx=%d\n", _cursesi_screen->ly,
338 		 _cursesi_screen->lx);
339 #endif
340 
341 	if (_cursesi_screen->curwin)
342 		domvcur(_cursesi_screen->ly, _cursesi_screen->lx,
343 			(int) win->cury, (int) win->curx);
344 	else {
345 		if (win->flags & __LEAVEOK) {
346 			curscr->cury = _cursesi_screen->ly;
347 			curscr->curx = _cursesi_screen->lx;
348 		} else {
349 			domvcur(_cursesi_screen->ly, _cursesi_screen->lx,
350 				win->cury, win->curx);
351 			curscr->cury = win->cury;
352 			curscr->curx = win->curx;
353 		}
354 	}
355 
356 	/* Don't leave the screen with attributes set. */
357 	__unsetattr(0);
358 	(void) fflush(_cursesi_screen->outfd);
359 	return (OK);
360 }
361 
362 /*
363  * makech --
364  *	Make a change on the screen.
365  */
366 static int
367 makech(wy)
368 	int	wy;
369 {
370 	WINDOW	*win;
371 	static __LDATA blank = {' ', 0, ' ', 0};
372 	__LDATA *nsp, *csp, *cp, *cep;
373 	int	clsp, nlsp;	/* Last space in lines. */
374 	int	lch, wx;
375 	char	*ce;
376 	attr_t	lspc;		/* Last space colour */
377 	attr_t	off, on;
378 
379 #ifdef __GNUC__
380 	nlsp = lspc = 0;	/* XXX gcc -Wuninitialized */
381 #endif
382 	if (_cursesi_screen->curwin)
383 		win = curscr;
384 	else
385 		win = __virtscr;
386 	/* Is the cursor still on the end of the last line? */
387 	if (wy > 0 && curscr->lines[wy - 1]->flags & __ISPASTEOL) {
388 		domvcur(_cursesi_screen->ly, _cursesi_screen->lx,
389 			_cursesi_screen->ly + 1, 0);
390 		_cursesi_screen->ly++;
391 		_cursesi_screen->lx = 0;
392 	}
393 	wx = *win->lines[wy]->firstchp;
394 	if (wx < 0)
395 		wx = 0;
396 	else
397 		if (wx >= win->maxx)
398 			return (OK);
399 	lch = *win->lines[wy]->lastchp;
400 	if (lch < 0)
401 		return (OK);
402 	else
403 		if (lch >= (int) win->maxx)
404 			lch = win->maxx - 1;
405 
406 	if (_cursesi_screen->curwin)
407 		csp = &blank;
408 	else
409 		csp = &curscr->lines[wy]->line[wx];
410 
411 	nsp = &win->lines[wy]->line[wx];
412 	if (__tc_ce && !_cursesi_screen->curwin) {
413 		cp = &win->lines[wy]->line[win->maxx - 1];
414 		lspc = cp->attr & __COLOR;
415 		while (cp->ch == ' ' && cp->attr == lspc)
416 			if (cp-- <= win->lines[wy]->line)
417 				break;
418 		nlsp = cp - win->lines[wy]->line;
419 		if (nlsp < 0)
420 			nlsp = 0;
421 	}
422 	if (!_cursesi_screen->curwin)
423 		ce = __tc_ce;
424 	else
425 		ce = NULL;
426 
427 	while (wx <= lch) {
428 		if (memcmp(nsp, csp, sizeof(__LDATA)) == 0) {
429 			if (wx <= lch) {
430 				while (wx <= lch &&
431 				    memcmp(nsp, csp, sizeof(__LDATA)) == 0) {
432 					nsp++;
433 					if (!_cursesi_screen->curwin)
434 						++csp;
435 					++wx;
436 				}
437 				continue;
438 			}
439 			break;
440 		}
441 		domvcur(_cursesi_screen->ly, _cursesi_screen->lx, wy, wx);
442 
443 #ifdef DEBUG
444 		__CTRACE("makech: 1: wx = %d, ly= %d, lx = %d, newy = %d, newx = %d\n",
445 		    wx, _cursesi_screen->ly, _cursesi_screen->lx, wy, wx);
446 #endif
447 		_cursesi_screen->ly = wy;
448 		_cursesi_screen->lx = wx;
449 		while (memcmp(nsp, csp, sizeof(__LDATA)) != 0 && wx <= lch) {
450 			if (ce != NULL &&
451 			    wx >= nlsp && nsp->ch == ' ' && nsp->attr == lspc) {
452 				/* Check for clear to end-of-line. */
453 				cep = &curscr->lines[wy]->line[win->maxx - 1];
454 				while (cep->ch == ' ' && cep->attr == lspc)
455 					if (cep-- <= csp)
456 						break;
457 				clsp = cep - curscr->lines[wy]->line -
458 				    win->begx * __LDATASIZE;
459 #ifdef DEBUG
460 				__CTRACE("makech: clsp = %d, nlsp = %d\n",
461 				    clsp, nlsp);
462 #endif
463 				if (((clsp - nlsp >= strlen(__tc_ce) &&
464 				    clsp < win->maxx * __LDATASIZE) ||
465 				    wy == win->maxy - 1) &&
466 				    (!(lspc & __COLOR) ||
467 				    ((lspc & __COLOR) && __tc_ut))) {
468 					__unsetattr(0);
469 					if ((lspc & __COLOR) !=
470 					    (curscr->wattr & __COLOR)) {
471 						__set_color(lspc);
472 						curscr->wattr &= ~__COLOR;
473 						curscr->wattr |= lspc & __COLOR;
474 					}
475 					tputs(__tc_ce, 0, __cputchar);
476 					_cursesi_screen->lx = wx + win->begx;
477 					while (wx++ <= clsp) {
478 						csp->ch = ' ';
479 						csp->attr = lspc;
480 						csp++;
481 					}
482 					return (OK);
483 				}
484 				ce = NULL;
485 			}
486 
487 			/*
488 			 * Unset colour if appropriate.  Check to see
489 			 * if we also turn off standout, underscore and
490 			 * attributes.
491 			 */
492 			if (!(nsp->attr & __COLOR) &&
493 			    (curscr->wattr & __COLOR)) {
494 				if (__tc_oc != NULL && __tc_cc == NULL)
495 					tputs(__tc_oc, 0, __cputchar);
496 				if (__tc_op != NULL) {
497 					tputs(__tc_op, 0, __cputchar);
498 					curscr->wattr &= __mask_op;
499 				}
500 			}
501 
502 			off = ~nsp->attr & curscr->wattr;
503 
504 			/*
505 			 * Unset attributes as appropriate.  Unset first
506 			 * so that the relevant attributes can be reset
507 			 * (because 'me' unsets 'mb', 'md', 'mh', 'mk',
508 			 * 'mp' and 'mr').  Check to see if we also turn off
509 			 * standout, attributes and colour.
510 			 */
511 			if (off & __TERMATTR && __tc_me != NULL) {
512 				tputs(__tc_me, 0, __cputchar);
513 				curscr->wattr &= __mask_me;
514 				off &= __mask_me;
515 			}
516 
517 			/*
518 			 * Exit underscore mode if appropriate.
519 			 * Check to see if we also turn off standout,
520 			 * attributes and colour.
521 			 */
522 			if (off & __UNDERSCORE && __tc_ue != NULL) {
523 				tputs(__tc_ue, 0, __cputchar);
524 				curscr->wattr &= __mask_ue;
525 				off &= __mask_ue;
526 			}
527 
528 			/*
529 			 * Exit standout mode as appropriate.
530 			 * Check to see if we also turn off underscore,
531 			 * attributes and colour.
532 			 * XXX
533 			 * Should use uc if so/se not available.
534 			 */
535 			if (off & __STANDOUT && __tc_se != NULL) {
536 				tputs(__tc_se, 0, __cputchar);
537 				curscr->wattr &= __mask_se;
538 				off &= __mask_se;
539 			}
540 
541 			if (off & __ALTCHARSET && __tc_ae != NULL) {
542 				tputs(__tc_ae, 0, __cputchar);
543 				curscr->wattr &= ~__ALTCHARSET;
544 			}
545 
546 			on = nsp->attr & ~curscr->wattr;
547 
548 			/*
549 			 * Enter standout mode if appropriate.
550 			 */
551 			if (on & __STANDOUT && __tc_so != NULL && __tc_se
552 			    != NULL) {
553 				tputs(__tc_so, 0, __cputchar);
554 				curscr->wattr |= __STANDOUT;
555 			}
556 
557 			/*
558 			 * Enter underscore mode if appropriate.
559 			 * XXX
560 			 * Should use uc if us/ue not available.
561 			 */
562 			if (on & __UNDERSCORE && __tc_us != NULL &&
563 			    __tc_ue != NULL) {
564 				tputs(__tc_us, 0, __cputchar);
565 				curscr->wattr |= __UNDERSCORE;
566 			}
567 
568 			/*
569 			 * Set other attributes as appropriate.
570 			 */
571 			if (__tc_me != NULL) {
572 				if (on & __BLINK && __tc_mb != NULL) {
573 					tputs(__tc_mb, 0, __cputchar);
574 					curscr->wattr |= __BLINK;
575 				}
576 				if (on & __BOLD && __tc_md != NULL) {
577 					tputs(__tc_md, 0, __cputchar);
578 					curscr->wattr |= __BOLD;
579 				}
580 				if (on & __DIM && __tc_mh != NULL) {
581 					tputs(__tc_mh, 0, __cputchar);
582 					curscr->wattr |= __DIM;
583 				}
584 				if (on & __BLANK && __tc_mk != NULL) {
585 					tputs(__tc_mk, 0, __cputchar);
586 					curscr->wattr |= __BLANK;
587 				}
588 				if (on & __PROTECT && __tc_mp != NULL) {
589 					tputs(__tc_mp, 0, __cputchar);
590 					curscr->wattr |= __PROTECT;
591 				}
592 				if (on & __REVERSE && __tc_mr != NULL) {
593 					tputs(__tc_mr, 0, __cputchar);
594 					curscr->wattr |= __REVERSE;
595 				}
596 			}
597 
598 			/* Set/change colour as appropriate. */
599 			if ((nsp->attr & __COLOR) && __tc_Co != NULL &&
600 			    (__tc_oc != NULL || __tc_op != NULL)) {
601 				if ((nsp->attr & __COLOR) !=
602 				    (curscr->wattr & __COLOR)) {
603 					__set_color(nsp->attr);
604 					curscr->wattr &= ~__COLOR;
605 					curscr->wattr |= nsp->attr &
606 					    __COLOR;
607 				}
608 			}
609 
610 			/* Enter/exit altcharset mode as appropriate. */
611 			if (on & __ALTCHARSET && __tc_as != NULL &&
612 			    __tc_ae != NULL) {
613 				tputs(__tc_as, 0, __cputchar);
614 				curscr->wattr |= __ALTCHARSET;
615 			}
616 
617 			wx++;
618 			if (wx >= win->maxx &&
619 			    wy == win->maxy - 1 && !_cursesi_screen->curwin)
620 				if (win->flags & __SCROLLOK) {
621 					if (win->flags & __ENDLINE)
622 						__unsetattr(1);
623 					if (!(win->flags & __SCROLLWIN)) {
624 						if (!_cursesi_screen->curwin) {
625 							csp->attr = nsp->attr;
626 							__cputchar((int)
627 							    (csp->ch =
628 							    nsp->ch));
629 						} else
630 							__cputchar((int) nsp->ch);
631 					}
632 					if (wx < curscr->maxx) {
633 						domvcur(_cursesi_screen->ly, wx,
634 						    (int) (win->maxy - 1),
635 						    (int) (win->maxx - 1));
636 					}
637 					_cursesi_screen->ly = win->maxy - 1;
638 					_cursesi_screen->lx = win->maxx - 1;
639 					return (OK);
640 				}
641 			if (wx < win->maxx || wy < win->maxy - 1 ||
642 			    !(win->flags & __SCROLLWIN)) {
643 				if (!_cursesi_screen->curwin) {
644 					csp->attr = nsp->attr;
645 					__cputchar((int) (csp->ch = nsp->ch));
646 					csp++;
647 				} else
648 					__cputchar((int) nsp->ch);
649 			}
650 #ifdef DEBUG
651 			__CTRACE("makech: putchar(%c)\n", nsp->ch & 0177);
652 #endif
653 			if (__tc_uc && ((nsp->attr & __STANDOUT) ||
654 			    (nsp->attr & __UNDERSCORE))) {
655 				__cputchar('\b');
656 				tputs(__tc_uc, 0, __cputchar);
657 			}
658 			nsp++;
659 #ifdef DEBUG
660 			__CTRACE("makech: 2: wx = %d, lx = %d\n", wx, _cursesi_screen->lx);
661 #endif
662 		}
663 		if (_cursesi_screen->lx == wx)	/* If no change. */
664 			break;
665 		_cursesi_screen->lx = wx;
666 		if (_cursesi_screen->lx >= COLS && __tc_am)
667 			_cursesi_screen->lx = COLS - 1;
668 		else
669 			if (wx >= win->maxx) {
670 				domvcur(_cursesi_screen->ly,
671 					_cursesi_screen->lx,
672 					_cursesi_screen->ly,
673 					(int) (win->maxx - 1));
674 				_cursesi_screen->lx = win->maxx - 1;
675 			}
676 #ifdef DEBUG
677 		__CTRACE("makech: 3: wx = %d, lx = %d\n", wx,
678 			 _cursesi_screen->lx);
679 #endif
680 	}
681 
682 	return (OK);
683 }
684 
685 /*
686  * domvcur --
687  *	Do a mvcur, leaving attributes if necessary.
688  */
689 static void
690 domvcur(oy, ox, ny, nx)
691 	int	oy, ox, ny, nx;
692 {
693 	__unsetattr(1);
694 	__mvcur(oy, ox, ny, nx, 1);
695 }
696 
697 /*
698  * Quickch() attempts to detect a pattern in the change of the window
699  * in order to optimize the change, e.g., scroll n lines as opposed to
700  * repainting the screen line by line.
701  */
702 
703 static void
704 quickch(void)
705 {
706 #define THRESH		(int) __virtscr->maxy / 4
707 
708 	__LINE *clp, *tmp1, *tmp2;
709 	int	bsize, curs, curw, starts, startw, i, j;
710 	int	n, target, cur_period, bot, top, sc_region;
711 	__LDATA buf[1024];
712 	u_int	blank_hash;
713 	attr_t	bcolor;
714 
715 #ifdef __GNUC__
716 	curs = curw = starts = startw = 0;	/* XXX gcc -Wuninitialized */
717 #endif
718 	/*
719 	 * Find how many lines from the top of the screen are unchanged.
720 	 */
721 	for (top = 0; top < __virtscr->maxy; top++)
722 		if (__virtscr->lines[top]->flags & __ISDIRTY &&
723 		    (__virtscr->lines[top]->hash != curscr->lines[top]->hash ||
724 		     memcmp(__virtscr->lines[top]->line,
725 			  curscr->lines[top]->line,
726 			  (size_t) __virtscr->maxx * __LDATASIZE) != 0))
727 			break;
728 		else
729 			__virtscr->lines[top]->flags &= ~__ISDIRTY;
730 	/*
731 	 * Find how many lines from bottom of screen are unchanged.
732 	 */
733 	for (bot = __virtscr->maxy - 1; bot >= 0; bot--)
734 		if (__virtscr->lines[bot]->flags & __ISDIRTY &&
735 		    (__virtscr->lines[bot]->hash != curscr->lines[bot]->hash ||
736 		     memcmp(__virtscr->lines[bot]->line,
737 			  curscr->lines[bot]->line,
738 			  (size_t) __virtscr->maxx * __LDATASIZE) != 0))
739 			break;
740 		else
741 			__virtscr->lines[bot]->flags &= ~__ISDIRTY;
742 
743 	/*
744 	 * Work round an xterm bug where inserting lines causes all the
745 	 * inserted lines to be covered with the background colour we
746 	 * set on the first line (even if we unset it for subsequent
747 	 * lines).
748 	 */
749 	bcolor = __virtscr->lines[min(top,
750 	    __virtscr->maxy - 1)]->line[0].attr & __COLOR;
751 	for (i = top + 1, j = 0; i < bot; i++) {
752 		if ((__virtscr->lines[i]->line[0].attr & __COLOR) != bcolor) {
753 			bcolor = __virtscr->lines[i]->line[__virtscr->maxx].
754 			    attr & __COLOR;
755 			j = i - top;
756 		} else
757 			break;
758 	}
759 	top += j;
760 
761 #ifdef NO_JERKINESS
762 	/*
763 	 * If we have a bottom unchanged region return.  Scrolling the
764 	 * bottom region up and then back down causes a screen jitter.
765 	 * This will increase the number of characters sent to the screen
766 	 * but it looks better.
767 	 */
768 	if (bot < __virtscr->maxy - 1)
769 		return;
770 #endif				/* NO_JERKINESS */
771 
772 	/*
773 	 * Search for the largest block of text not changed.
774 	 * Invariants of the loop:
775 	 * - Startw is the index of the beginning of the examined block in
776 	 *   __virtscr.
777 	 * - Starts is the index of the beginning of the examined block in
778 	 *   curscr.
779 	 * - Curw is the index of one past the end of the exmined block in
780 	 *   __virtscr.
781 	 * - Curs is the index of one past the end of the exmined block in
782 	 *   curscr.
783 	 * - bsize is the current size of the examined block.
784 	*/
785 
786 	for (bsize = bot - top; bsize >= THRESH; bsize--) {
787 		for (startw = top; startw <= bot - bsize; startw++)
788 			for (starts = top; starts <= bot - bsize;
789 			    starts++) {
790 				for (curw = startw, curs = starts;
791 				    curs < starts + bsize; curw++, curs++)
792 					if (__virtscr->lines[curw]->hash !=
793 					    curscr->lines[curs]->hash)
794 						break;
795 				if (curs != starts + bsize)
796 					continue;
797 				for (curw = startw, curs = starts;
798 				    curs < starts + bsize; curw++, curs++)
799 					if (memcmp(__virtscr->lines[curw]->line,
800 					    curscr->lines[curs]->line,
801 					    (size_t) __virtscr->maxx *
802 					    __LDATASIZE) != 0)
803 						break;
804 				if (curs == starts + bsize)
805 					goto done;
806 			}
807 	}
808 done:
809 
810 	/* Did not find anything */
811 	if (bsize < THRESH)
812 		return;
813 
814 #ifdef DEBUG
815 	__CTRACE("quickch:bsize=%d,starts=%d,startw=%d,curw=%d,curs=%d,top=%d,bot=%d\n",
816 	    bsize, starts, startw, curw, curs, top, bot);
817 #endif
818 
819 	/*
820 	 * Make sure that there is no overlap between the bottom and top
821 	 * regions and the middle scrolled block.
822 	 */
823 	if (bot < curs)
824 		bot = curs - 1;
825 	if (top > starts)
826 		top = starts;
827 
828 	n = startw - starts;
829 
830 #ifdef DEBUG
831 	__CTRACE("#####################################\n");
832 	for (i = 0; i < curscr->maxy; i++) {
833 		__CTRACE("C: %d:", i);
834 		__CTRACE(" 0x%x \n", curscr->lines[i]->hash);
835 		for (j = 0; j < curscr->maxx; j++)
836 			__CTRACE("%c", curscr->lines[i]->line[j].ch);
837 		__CTRACE("\n");
838 		__CTRACE(" attr:");
839 		for (j = 0; j < curscr->maxx; j++)
840 			__CTRACE(" %x", curscr->lines[i]->line[j].attr);
841 		__CTRACE("\n");
842 		__CTRACE("W: %d:", i);
843 		__CTRACE(" 0x%x \n", __virtscr->lines[i]->hash);
844 		__CTRACE(" 0x%x ", __virtscr->lines[i]->flags);
845 		for (j = 0; j < __virtscr->maxx; j++)
846 			__CTRACE("%c", __virtscr->lines[i]->line[j].ch);
847 		__CTRACE("\n");
848 		__CTRACE(" attr:");
849 		for (j = 0; j < __virtscr->maxx; j++)
850 			__CTRACE(" %x", __virtscr->lines[i]->line[j].attr);
851 		__CTRACE("\n");
852 	}
853 #endif
854 
855 	/* So we don't have to call __hash() each time */
856 	for (i = 0; i < __virtscr->maxx; i++) {
857 		buf[i].ch = ' ';
858 		buf[i].bch = ' ';
859 		buf[i].attr = 0;
860 		buf[i].battr = 0;
861 	}
862 	blank_hash = __hash((char *)(void *)buf,
863 	    (int) (__virtscr->maxx * __LDATASIZE));
864 
865 	/*
866 	 * Perform the rotation to maintain the consistency of curscr.
867 	 * This is hairy since we are doing an *in place* rotation.
868 	 * Invariants of the loop:
869 	 * - I is the index of the current line.
870 	 * - Target is the index of the target of line i.
871 	 * - Tmp1 points to current line (i).
872 	 * - Tmp2 and points to target line (target);
873 	 * - Cur_period is the index of the end of the current period.
874 	 *   (see below).
875 	 *
876 	 * There are 2 major issues here that make this rotation non-trivial:
877 	 * 1.  Scrolling in a scrolling region bounded by the top
878 	 *     and bottom regions determined (whose size is sc_region).
879 	 * 2.  As a result of the use of the mod function, there may be a
880 	 *     period introduced, i.e., 2 maps to 4, 4 to 6, n-2 to 0, and
881 	 *     0 to 2, which then causes all odd lines not to be rotated.
882 	 *     To remedy this, an index of the end ( = beginning) of the
883 	 *     current 'period' is kept, cur_period, and when it is reached,
884 	 *     the next period is started from cur_period + 1 which is
885 	 *     guaranteed not to have been reached since that would mean that
886 	 *     all records would have been reached. (think about it...).
887 	 *
888 	 * Lines in the rotation can have 3 attributes which are marked on the
889 	 * line so that curscr is consistent with the visual screen.
890 	 * 1.  Not dirty -- lines inside the scrolled block, top region or
891 	 *                  bottom region.
892 	 * 2.  Blank lines -- lines in the differential of the scrolling
893 	 *		      region adjacent to top and bot regions
894 	 *                    depending on scrolling direction.
895 	 * 3.  Dirty line -- all other lines are marked dirty.
896 	 */
897 	sc_region = bot - top + 1;
898 	i = top;
899 	tmp1 = curscr->lines[top];
900 	cur_period = top;
901 	for (j = top; j <= bot; j++) {
902 		target = (i - top + n + sc_region) % sc_region + top;
903 		tmp2 = curscr->lines[target];
904 		curscr->lines[target] = tmp1;
905 		/* Mark block as clean and blank out scrolled lines. */
906 		clp = curscr->lines[target];
907 #ifdef DEBUG
908 		__CTRACE("quickch: n=%d startw=%d curw=%d i = %d target=%d ",
909 		    n, startw, curw, i, target);
910 #endif
911 		if ((target >= startw && target < curw) || target < top
912 		    || target > bot) {
913 #ifdef DEBUG
914 			__CTRACE("-- notdirty\n");
915 #endif
916 			__virtscr->lines[target]->flags &= ~__ISDIRTY;
917 		} else
918 			if ((n > 0 && target >= top && target < top + n) ||
919 			    (n < 0 && target <= bot && target > bot + n)) {
920 				if (clp->hash != blank_hash || memcmp(clp->line,
921 				    buf, (size_t) __virtscr->maxx * __LDATASIZE) !=0) {
922 					(void)memcpy(clp->line,  buf,
923 					    (size_t) __virtscr->maxx * __LDATASIZE);
924 #ifdef DEBUG
925 					__CTRACE("-- blanked out: dirty\n");
926 #endif
927 					clp->hash = blank_hash;
928 					__touchline(__virtscr, target, 0, (int) __virtscr->maxx - 1);
929 				} else {
930 #ifdef DEBUG
931 					__CTRACE(" -- blank line already: dirty\n");
932 #endif
933 					__touchline(__virtscr, target, 0, (int) __virtscr->maxx - 1);
934 				}
935 			} else {
936 #ifdef DEBUG
937 				__CTRACE(" -- dirty\n");
938 #endif
939 				__touchline(__virtscr, target, 0, (int) __virtscr->maxx - 1);
940 			}
941 		if (target == cur_period) {
942 			i = target + 1;
943 			tmp1 = curscr->lines[i];
944 			cur_period = i;
945 		} else {
946 			tmp1 = tmp2;
947 			i = target;
948 		}
949 	}
950 #ifdef DEBUG
951 	__CTRACE("$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$\n");
952 	for (i = 0; i < curscr->maxy; i++) {
953 		__CTRACE("C: %d:", i);
954 		for (j = 0; j < curscr->maxx; j++)
955 			__CTRACE("%c", curscr->lines[i]->line[j].ch);
956 		__CTRACE("\n");
957 		__CTRACE("W: %d:", i);
958 		for (j = 0; j < __virtscr->maxx; j++)
959 			__CTRACE("%c", __virtscr->lines[i]->line[j].ch);
960 		__CTRACE("\n");
961 	}
962 #endif
963 	if (n != 0)
964 		scrolln(starts, startw, curs, bot, top);
965 }
966 
967 /*
968  * scrolln --
969  *	Scroll n lines, where n is starts - startw.
970  */
971 static void /* ARGSUSED */
972 scrolln(starts, startw, curs, bot, top)
973 	int	starts, startw, curs, bot, top;
974 {
975 	int	i, oy, ox, n;
976 
977 	oy = curscr->cury;
978 	ox = curscr->curx;
979 	n = starts - startw;
980 
981 	/*
982 	 * XXX
983 	 * The initial tests that set __noqch don't let us reach here unless
984 	 * we have either cs + ho + SF/sf/SR/sr, or AL + DL.  SF/sf and SR/sr
985 	 * scrolling can only shift the entire scrolling region, not just a
986 	 * part of it, which means that the quickch() routine is going to be
987 	 * sadly disappointed in us if we don't have cs as well.
988 	 *
989 	 * If cs, ho and SF/sf are set, can use the scrolling region.  Because
990 	 * the cursor position after cs is undefined, we need ho which gives us
991 	 * the ability to move to somewhere without knowledge of the current
992 	 * location of the cursor.  Still call __mvcur() anyway, to update its
993 	 * idea of where the cursor is.
994 	 *
995 	 * When the scrolling region has been set, the cursor has to be at the
996 	 * last line of the region to make the scroll happen.
997 	 *
998 	 * Doing SF/SR or AL/DL appears faster on the screen than either sf/sr
999 	 * or AL/DL, and, some terminals have AL/DL, sf/sr, and cs, but not
1000 	 * SF/SR.  So, if we're scrolling almost all of the screen, try and use
1001 	 * AL/DL, otherwise use the scrolling region.  The "almost all" is a
1002 	 * shameless hack for vi.
1003 	 */
1004 	if (n > 0) {
1005 		if (__tc_cs != NULL && __tc_ho != NULL && (__tc_SF != NULL ||
1006 		    ((__tc_AL == NULL || __tc_DL == NULL ||
1007 		    top > 3 || bot + 3 < __virtscr->maxy) &&
1008 		    __tc_sf != NULL))) {
1009 			tputs(__tscroll(__tc_cs, top, bot + 1), 0, __cputchar);
1010 			__mvcur(oy, ox, 0, 0, 1);
1011 			tputs(__tc_ho, 0, __cputchar);
1012 			__mvcur(0, 0, bot, 0, 1);
1013 			if (__tc_SF != NULL)
1014 				tputs(__tscroll(__tc_SF, n, 0), 0, __cputchar);
1015 			else
1016 				for (i = 0; i < n; i++)
1017 					tputs(__tc_sf, 0, __cputchar);
1018 			tputs(__tscroll(__tc_cs, 0, (int) __virtscr->maxy), 0,
1019 			    __cputchar);
1020 			__mvcur(bot, 0, 0, 0, 1);
1021 			tputs(__tc_ho, 0, __cputchar);
1022 			__mvcur(0, 0, oy, ox, 1);
1023 			return;
1024 		}
1025 
1026 		/* Scroll up the block. */
1027 		if (__tc_SF != NULL && top == 0) {
1028 			__mvcur(oy, ox, bot, 0, 1);
1029 			tputs(__tscroll(__tc_SF, n, 0), 0, __cputchar);
1030 		} else
1031 			if (__tc_DL != NULL) {
1032 				__mvcur(oy, ox, top, 0, 1);
1033 				tputs(__tscroll(__tc_DL, n, 0), 0, __cputchar);
1034 			} else
1035 				if (__tc_dl != NULL) {
1036 					__mvcur(oy, ox, top, 0, 1);
1037 					for (i = 0; i < n; i++)
1038 						tputs(__tc_dl, 0, __cputchar);
1039 				} else
1040 					if (__tc_sf != NULL && top == 0) {
1041 						__mvcur(oy, ox, bot, 0, 1);
1042 						for (i = 0; i < n; i++)
1043 							tputs(__tc_sf, 0,
1044 							    __cputchar);
1045 					} else
1046 						abort();
1047 
1048 		/* Push down the bottom region. */
1049 		__mvcur(top, 0, bot - n + 1, 0, 1);
1050 		if (__tc_AL != NULL)
1051 			tputs(__tscroll(__tc_AL, n, 0), 0, __cputchar);
1052 		else
1053 			if (__tc_al != NULL)
1054 				for (i = 0; i < n; i++)
1055 					tputs(__tc_al, 0, __cputchar);
1056 			else
1057 				abort();
1058 		__mvcur(bot - n + 1, 0, oy, ox, 1);
1059 	} else {
1060 		/*
1061 		 * !!!
1062 		 * n < 0
1063 		 *
1064 		 * If cs, ho and SR/sr are set, can use the scrolling region.
1065 		 * See the above comments for details.
1066 		 */
1067 		if (__tc_cs != NULL && __tc_ho != NULL && (__tc_SR != NULL ||
1068 		    ((__tc_AL == NULL || __tc_DL == NULL || top > 3 ||
1069 		    bot + 3 < __virtscr->maxy) && __tc_sr != NULL))) {
1070 			tputs(__tscroll(__tc_cs, top, bot + 1), 0, __cputchar);
1071 			__mvcur(oy, ox, 0, 0, 1);
1072 			tputs(__tc_ho, 0, __cputchar);
1073 			__mvcur(0, 0, top, 0, 1);
1074 
1075 			if (__tc_SR != NULL)
1076 				tputs(__tscroll(__tc_SR, -n, 0), 0, __cputchar);
1077 			else
1078 				for (i = n; i < 0; i++)
1079 					tputs(__tc_sr, 0, __cputchar);
1080 			tputs(__tscroll(__tc_cs, 0, (int) __virtscr->maxy), 0,
1081 			    __cputchar);
1082 			__mvcur(top, 0, 0, 0, 1);
1083 			tputs(__tc_ho, 0, __cputchar);
1084 			__mvcur(0, 0, oy, ox, 1);
1085 			return;
1086 		}
1087 
1088 		/* Preserve the bottom lines. */
1089 		__mvcur(oy, ox, bot + n + 1, 0, 1);
1090 		if (__tc_SR != NULL && bot == __virtscr->maxy)
1091 			tputs(__tscroll(__tc_SR, -n, 0), 0, __cputchar);
1092 		else
1093 			if (__tc_DL != NULL)
1094 				tputs(__tscroll(__tc_DL, -n, 0), 0, __cputchar);
1095 			else
1096 				if (__tc_dl != NULL)
1097 					for (i = n; i < 0; i++)
1098 						tputs(__tc_dl, 0, __cputchar);
1099 				else
1100 					if (__tc_sr != NULL &&
1101 					    bot == __virtscr->maxy)
1102 						for (i = n; i < 0; i++)
1103 							tputs(__tc_sr, 0,
1104 							    __cputchar);
1105 					else
1106 						abort();
1107 
1108 		/* Scroll the block down. */
1109 		__mvcur(bot + n + 1, 0, top, 0, 1);
1110 		if (__tc_AL != NULL)
1111 			tputs(__tscroll(__tc_AL, -n, 0), 0, __cputchar);
1112 		else
1113 			if (__tc_al != NULL)
1114 				for (i = n; i < 0; i++)
1115 					tputs(__tc_al, 0, __cputchar);
1116 			else
1117 				abort();
1118 		__mvcur(top, 0, oy, ox, 1);
1119 	}
1120 }
1121 
1122 /*
1123  * __unsetattr --
1124  *	Unset attributes on curscr.  Leave standout, attribute and colour
1125  *	modes if necessary (!ms).  Always leave altcharset (xterm at least
1126  *	ignores a cursor move if we don't).
1127  */
1128 void /* ARGSUSED */
1129 __unsetattr(int checkms)
1130 {
1131 	int	isms;
1132 
1133 	if (checkms)
1134 		if (!__tc_ms) {
1135 			isms = 1;
1136 		} else {
1137 			isms = 0;
1138 		}
1139 	else
1140 		isms = 1;
1141 #ifdef DEBUG
1142 	__CTRACE("__unsetattr: checkms = %d, ms = %s, wattr = %08x\n",
1143 	    checkms, __tc_ms ? "TRUE" : "FALSE", curscr->wattr);
1144 #endif
1145 
1146 	/*
1147          * Don't leave the screen in standout mode (check against ms).  Check
1148 	 * to see if we also turn off underscore, attributes and colour.
1149 	 */
1150 	if (curscr->wattr & __STANDOUT && isms) {
1151 		tputs(__tc_se, 0, __cputchar);
1152 		curscr->wattr &= __mask_se;
1153 	}
1154 	/*
1155 	 * Don't leave the screen in underscore mode (check against ms).
1156 	 * Check to see if we also turn off attributes.  Assume that we
1157 	 * also turn off colour.
1158 	 */
1159 	if (curscr->wattr & __UNDERSCORE && isms) {
1160 		tputs(__tc_ue, 0, __cputchar);
1161 		curscr->wattr &= __mask_ue;
1162 	}
1163 	/*
1164 	 * Don't leave the screen with attributes set (check against ms).
1165 	 * Assume that also turn off colour.
1166 	 */
1167 	if (curscr->wattr & __TERMATTR && isms) {
1168 		tputs(__tc_me, 0, __cputchar);
1169 		curscr->wattr &= __mask_me;
1170 	}
1171 	/* Don't leave the screen with altcharset set (don't check ms). */
1172 	if (curscr->wattr & __ALTCHARSET) {
1173 		tputs(__tc_ae, 0, __cputchar);
1174 		curscr->wattr &= ~__ALTCHARSET;
1175 	}
1176 	/* Don't leave the screen with colour set (check against ms). */
1177 	if (curscr->wattr & __COLOR && isms) {
1178 		if (__tc_oc != NULL && __tc_cc == NULL)
1179 			tputs(__tc_oc, 0, __cputchar);
1180 		if (__tc_op != NULL) {
1181 			tputs(__tc_op, 0, __cputchar);
1182 			curscr->wattr &= __mask_op;
1183 		}
1184 	}
1185 }
1186