xref: /netbsd-src/lib/libcurses/color.c (revision 181254a7b1bdde6873432bffef2d2decc4b5c22f)
1 /*	$NetBSD: color.c,v 1.41 2017/01/06 13:53:18 roy Exp $	*/
2 
3 /*
4  * Copyright (c) 2000 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Julian Coleman.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 #ifndef lint
34 __RCSID("$NetBSD: color.c,v 1.41 2017/01/06 13:53:18 roy Exp $");
35 #endif				/* not lint */
36 
37 #include "curses.h"
38 #include "curses_private.h"
39 
40 /* Have we initialised colours? */
41 int	__using_color = 0;
42 
43 /* Default colour number */
44 attr_t	__default_color = 0;
45 
46 /* Default colour pair values - white on black. */
47 struct __pair	__default_pair = {COLOR_WHITE, COLOR_BLACK, 0};
48 
49 /* Default colour values */
50 /* Flags for colours and pairs */
51 #define	__USED		0x01
52 
53 static void
54 __change_pair(short);
55 
56 static int
57 init_color_value(short, short, short, short);
58 
59 /*
60  * has_colors --
61  *	Check if terminal has colours.
62  */
63 bool
64 has_colors(void)
65 {
66 	if (max_colors > 0 && max_pairs > 0 &&
67 	    ((set_a_foreground != NULL && set_a_background != NULL) ||
68 		initialize_pair != NULL || initialize_color != NULL ||
69 		(set_background != NULL && set_foreground != NULL)))
70 		return true;
71 	else
72 		return false;
73 }
74 
75 /*
76  * can_change_color --
77  *	Check if terminal can change colours.
78  */
79 bool
80 can_change_color(void)
81 {
82 	return can_change ? true : false;
83 }
84 
85 /*
86  * start_color --
87  *	Initialise colour support.
88  */
89 int
90 start_color(void)
91 {
92 	int			 i;
93 	attr_t			 temp_nc;
94 	struct __winlist	*wlp;
95 	WINDOW			*win;
96 	int			 y, x;
97 
98 	if (has_colors() == FALSE)
99 		return ERR;
100 
101 	/* Max colours and colour pairs */
102 	if (max_colors == -1)
103 		COLORS = 0;
104 	else {
105 		COLORS = max_colors > MAX_COLORS ? MAX_COLORS : max_colors;
106 		if (max_pairs == -1) {
107 			COLOR_PAIRS = 0;
108 			COLORS = 0;
109 		} else {
110 			COLOR_PAIRS = (max_pairs > MAX_PAIRS - 1 ?
111 			    MAX_PAIRS - 1 : max_pairs);
112 			 /* Use the last colour pair for curses default. */
113 			__default_color = COLOR_PAIR(MAX_PAIRS - 1);
114 		}
115 	}
116 	if (!COLORS)
117 		return ERR;
118 
119 	_cursesi_screen->COLORS = COLORS;
120 	_cursesi_screen->COLOR_PAIRS = COLOR_PAIRS;
121 
122 	/* Reset terminal colour and colour pairs. */
123 	if (orig_colors != NULL)
124 		tputs(orig_colors, 0, __cputchar);
125 	if (orig_pair != NULL) {
126 		tputs(orig_pair, 0, __cputchar);
127 		curscr->wattr &= _cursesi_screen->mask_op;
128 	}
129 
130 	/* Type of colour manipulation - ANSI/TEK/HP/other */
131 	if (set_a_foreground != NULL && set_a_background != NULL)
132 		_cursesi_screen->color_type = COLOR_ANSI;
133 	else if (initialize_pair != NULL)
134 		_cursesi_screen->color_type = COLOR_HP;
135 	else if (initialize_color != NULL)
136 		_cursesi_screen->color_type = COLOR_TEK;
137 	else if (set_foreground != NULL && set_background != NULL)
138 		_cursesi_screen->color_type = COLOR_OTHER;
139 	else
140 		return(ERR);		/* Unsupported colour method */
141 
142 #ifdef DEBUG
143 	__CTRACE(__CTRACE_COLOR, "start_color: COLORS = %d, COLOR_PAIRS = %d",
144 	    COLORS, COLOR_PAIRS);
145 	switch (_cursesi_screen->color_type) {
146 	case COLOR_ANSI:
147 		__CTRACE(__CTRACE_COLOR, " (ANSI style)\n");
148 		break;
149 	case COLOR_HP:
150 		__CTRACE(__CTRACE_COLOR, " (HP style)\n");
151 		break;
152 	case COLOR_TEK:
153 		__CTRACE(__CTRACE_COLOR, " (Tektronics style)\n");
154 		break;
155 	case COLOR_OTHER:
156 		__CTRACE(__CTRACE_COLOR, " (Other style)\n");
157 		break;
158 	}
159 #endif
160 
161 	/*
162 	 * Attributes that cannot be used with color.
163 	 * Store these in an attr_t for wattrset()/wattron().
164 	 */
165 	_cursesi_screen->nca = __NORMAL;
166 	if (no_color_video != -1) {
167 		temp_nc = (attr_t)t_no_color_video(_cursesi_screen->term);
168 		if (temp_nc & 0x0001)
169 			_cursesi_screen->nca |= __STANDOUT;
170 		if (temp_nc & 0x0002)
171 			_cursesi_screen->nca |= __UNDERSCORE;
172 		if (temp_nc & 0x0004)
173 			_cursesi_screen->nca |= __REVERSE;
174 		if (temp_nc & 0x0008)
175 			_cursesi_screen->nca |= __BLINK;
176 		if (temp_nc & 0x0010)
177 			_cursesi_screen->nca |= __DIM;
178 		if (temp_nc & 0x0020)
179 			_cursesi_screen->nca |= __BOLD;
180 		if (temp_nc & 0x0040)
181 			_cursesi_screen->nca |= __BLANK;
182 		if (temp_nc & 0x0080)
183 			_cursesi_screen->nca |= __PROTECT;
184 		if (temp_nc & 0x0100)
185 			_cursesi_screen->nca |= __ALTCHARSET;
186 	}
187 #ifdef DEBUG
188 	__CTRACE(__CTRACE_COLOR, "start_color: _cursesi_screen->nca = %08x\n",
189 	    _cursesi_screen->nca);
190 #endif
191 
192 	/* Set up initial 8 colours */
193 #define	RGB_ON	680	/* Allow for bright colours */
194 	if (COLORS >= COLOR_BLACK)
195 		(void)init_color_value(COLOR_BLACK, 0, 0, 0);
196 	if (COLORS >= COLOR_RED)
197 		(void)init_color_value(COLOR_RED, RGB_ON, 0, 0);
198 	if (COLORS >= COLOR_GREEN)
199 		(void)init_color_value(COLOR_GREEN, 0, RGB_ON, 0);
200 	if (COLORS >= COLOR_YELLOW)
201 		(void)init_color_value(COLOR_YELLOW, RGB_ON, RGB_ON, 0);
202 	if (COLORS >= COLOR_BLUE)
203 		(void)init_color_value(COLOR_BLUE, 0, 0, RGB_ON);
204 	if (COLORS >= COLOR_MAGENTA)
205 		(void)init_color_value(COLOR_MAGENTA, RGB_ON, 0, RGB_ON);
206 	if (COLORS >= COLOR_CYAN)
207 		(void)init_color_value(COLOR_CYAN, 0, RGB_ON, RGB_ON);
208 	if (COLORS >= COLOR_WHITE)
209 		(void)init_color_value(COLOR_WHITE, RGB_ON, RGB_ON, RGB_ON);
210 
211 	/* Initialise other colours */
212 	for (i = 8; i < COLORS; i++) {
213 		_cursesi_screen->colours[i].red = 0;
214 		_cursesi_screen->colours[i].green = 0;
215 		_cursesi_screen->colours[i].blue = 0;
216 		_cursesi_screen->colours[i].flags = 0;
217 	}
218 
219 	/* Initialise pair 0 to default colours. */
220 	_cursesi_screen->colour_pairs[0].fore = -1;
221 	_cursesi_screen->colour_pairs[0].back = -1;
222 	_cursesi_screen->colour_pairs[0].flags = 0;
223 
224 	/* Initialise user colour pairs to default (white on black) */
225 	for (i = 0; i < COLOR_PAIRS; i++) {
226 		_cursesi_screen->colour_pairs[i].fore = COLOR_WHITE;
227 		_cursesi_screen->colour_pairs[i].back = COLOR_BLACK;
228 		_cursesi_screen->colour_pairs[i].flags = 0;
229 	}
230 
231 	/* Initialise default colour pair. */
232 	_cursesi_screen->colour_pairs[PAIR_NUMBER(__default_color)].fore =
233 	    __default_pair.fore;
234 	_cursesi_screen->colour_pairs[PAIR_NUMBER(__default_color)].back =
235 	    __default_pair.back;
236 	_cursesi_screen->colour_pairs[PAIR_NUMBER(__default_color)].flags =
237 	    __default_pair.flags;
238 
239 	__using_color = 1;
240 
241 	/* Set all positions on all windows to curses default colours. */
242 	for (wlp = _cursesi_screen->winlistp; wlp != NULL; wlp = wlp->nextp) {
243 		win = wlp->winp;
244 		if (wlp->winp != __virtscr && wlp->winp != curscr) {
245 			/* Set color attribute on other windows */
246 			win->battr |= __default_color;
247 			for (y = 0; y < win->maxy; y++) {
248 				for (x = 0; x < win->maxx; x++) {
249 					win->alines[y]->line[x].attr &= ~__COLOR;
250 					win->alines[y]->line[x].attr |= __default_color;
251 				}
252 			}
253 			__touchwin(win);
254 		}
255 	}
256 
257 	return(OK);
258 }
259 
260 /*
261  * init_pair --
262  *	Set pair foreground and background colors.
263  *	Our default colour ordering is ANSI - 1 = red, 4 = blue, 3 = yellow,
264  *	6 = cyan.  The older style (Sb/Sf) uses 1 = blue, 4 = red, 3 = cyan,
265  *	6 = yellow, so we swap them here and in pair_content().
266  */
267 int
268 init_pair(short pair, short fore, short back)
269 {
270 	int	changed;
271 
272 #ifdef DEBUG
273 	__CTRACE(__CTRACE_COLOR, "init_pair: %d, %d, %d\n", pair, fore, back);
274 #endif
275 
276 	if (pair < 0 || pair >= COLOR_PAIRS)
277 		return ERR;
278 
279 	if (pair == 0) /* Ignore request for pair 0, it is default. */
280 		return OK;
281 
282 	if (fore >= COLORS)
283 		return ERR;
284 	if (back >= COLORS)
285 		return ERR;
286 
287 	/* Swap red/blue and yellow/cyan */
288 	if (_cursesi_screen->color_type == COLOR_OTHER) {
289 		switch (fore) {
290 		case COLOR_RED:
291 			fore = COLOR_BLUE;
292 			break;
293 		case COLOR_BLUE:
294 			fore = COLOR_RED;
295 			break;
296 		case COLOR_YELLOW:
297 			fore = COLOR_CYAN;
298 			break;
299 		case COLOR_CYAN:
300 			fore = COLOR_YELLOW;
301 			break;
302 		}
303 		switch (back) {
304 		case COLOR_RED:
305 			back = COLOR_BLUE;
306 			break;
307 		case COLOR_BLUE:
308 			back = COLOR_RED;
309 			break;
310 		case COLOR_YELLOW:
311 			back = COLOR_CYAN;
312 			break;
313 		case COLOR_CYAN:
314 			back = COLOR_YELLOW;
315 			break;
316 		}
317 	}
318 
319 	if ((_cursesi_screen->colour_pairs[pair].flags & __USED) &&
320 	    (fore != _cursesi_screen->colour_pairs[pair].fore ||
321 	     back != _cursesi_screen->colour_pairs[pair].back))
322 		changed = 1;
323 	else
324 		changed = 0;
325 
326 	_cursesi_screen->colour_pairs[pair].flags |= __USED;
327 	_cursesi_screen->colour_pairs[pair].fore = fore;
328 	_cursesi_screen->colour_pairs[pair].back = back;
329 
330 	/* XXX: need to initialise HP style (Ip) */
331 
332 	if (changed)
333 		__change_pair(pair);
334 	return OK;
335 }
336 
337 /*
338  * pair_content --
339  *	Get pair foreground and background colours.
340  */
341 int
342 pair_content(short pair, short *forep, short *backp)
343 {
344 	if (pair < 0 || pair > _cursesi_screen->COLOR_PAIRS)
345 		return ERR;
346 
347 	*forep = _cursesi_screen->colour_pairs[pair].fore;
348 	*backp = _cursesi_screen->colour_pairs[pair].back;
349 
350 	/* Swap red/blue and yellow/cyan */
351 	if (_cursesi_screen->color_type == COLOR_OTHER) {
352 		switch (*forep) {
353 		case COLOR_RED:
354 			*forep = COLOR_BLUE;
355 			break;
356 		case COLOR_BLUE:
357 			*forep = COLOR_RED;
358 			break;
359 		case COLOR_YELLOW:
360 			*forep = COLOR_CYAN;
361 			break;
362 		case COLOR_CYAN:
363 			*forep = COLOR_YELLOW;
364 			break;
365 		}
366 		switch (*backp) {
367 		case COLOR_RED:
368 			*backp = COLOR_BLUE;
369 			break;
370 		case COLOR_BLUE:
371 			*backp = COLOR_RED;
372 			break;
373 		case COLOR_YELLOW:
374 			*backp = COLOR_CYAN;
375 			break;
376 		case COLOR_CYAN:
377 			*backp = COLOR_YELLOW;
378 			break;
379 		}
380 	}
381 	return OK;
382 }
383 
384 /*
385  * init_color_Value --
386  *	Set colour red, green and blue values.
387  */
388 static int
389 init_color_value(short color, short red, short green, short blue)
390 {
391 	if (color < 0 || color >= _cursesi_screen->COLORS)
392 		return ERR;
393 
394 	_cursesi_screen->colours[color].red = red;
395 	_cursesi_screen->colours[color].green = green;
396 	_cursesi_screen->colours[color].blue = blue;
397 	return OK;
398 }
399 
400 /*
401  * init_color --
402  *	Set colour red, green and blue values.
403  *	Change color on screen.
404  */
405 int
406 init_color(short color, short red, short green, short blue)
407 {
408 #ifdef DEBUG
409 	__CTRACE(__CTRACE_COLOR, "init_color: %d, %d, %d, %d\n",
410 	    color, red, green, blue);
411 #endif
412 	if (init_color_value(color, red, green, blue) == ERR)
413 		return ERR;
414 	if (!can_change || t_initialize_color(_cursesi_screen->term) == NULL)
415 		return ERR;
416 	tputs(tiparm(t_initialize_color(_cursesi_screen->term),
417 	             color, red, green, blue), 0, __cputchar);
418 	return OK;
419 }
420 
421 /*
422  * color_content --
423  *	Get colour red, green and blue values.
424  */
425 int
426 color_content(short color, short *redp, short *greenp, short *bluep)
427 {
428 	if (color < 0 || color >= _cursesi_screen->COLORS)
429 		return ERR;
430 
431 	*redp = _cursesi_screen->colours[color].red;
432 	*greenp = _cursesi_screen->colours[color].green;
433 	*bluep = _cursesi_screen->colours[color].blue;
434 	return OK;
435 }
436 
437 /*
438  * use_default_colors --
439  *	Use terminal default colours instead of curses default colour.
440   */
441 int
442 use_default_colors()
443 {
444 #ifdef DEBUG
445 	__CTRACE(__CTRACE_COLOR, "use_default_colors\n");
446 #endif
447 
448 	return (assume_default_colors(-1, -1));
449 }
450 
451 /*
452  * assume_default_colors --
453  *	Set the default foreground and background colours.
454  */
455 int
456 assume_default_colors(short fore, short back)
457 {
458 #ifdef DEBUG
459 	__CTRACE(__CTRACE_COLOR, "assume_default_colors: %d, %d\n",
460 	    fore, back);
461 	__CTRACE(__CTRACE_COLOR, "assume_default_colors: default_colour = %d, pair_number = %d\n", __default_color, PAIR_NUMBER(__default_color));
462 #endif
463 
464 	/* Swap red/blue and yellow/cyan */
465 	if (_cursesi_screen->color_type == COLOR_OTHER) {
466 		switch (fore) {
467 		case COLOR_RED:
468 			fore = COLOR_BLUE;
469 			break;
470 		case COLOR_BLUE:
471 			fore = COLOR_RED;
472 			break;
473 		case COLOR_YELLOW:
474 			fore = COLOR_CYAN;
475 			break;
476 		case COLOR_CYAN:
477 			fore = COLOR_YELLOW;
478 			break;
479 		}
480 		switch (back) {
481 		case COLOR_RED:
482 			back = COLOR_BLUE;
483 			break;
484 		case COLOR_BLUE:
485 			back = COLOR_RED;
486 			break;
487 		case COLOR_YELLOW:
488 			back = COLOR_CYAN;
489 			break;
490 		case COLOR_CYAN:
491 			back = COLOR_YELLOW;
492 			break;
493 		}
494 	}
495 	__default_pair.fore = fore;
496 	__default_pair.back = back;
497 	__default_pair.flags = __USED;
498 
499 	if (COLOR_PAIRS) {
500 		_cursesi_screen->colour_pairs[PAIR_NUMBER(__default_color)].fore = fore;
501 		_cursesi_screen->colour_pairs[PAIR_NUMBER(__default_color)].back = back;
502 		_cursesi_screen->colour_pairs[PAIR_NUMBER(__default_color)].flags = __USED;
503 	}
504 
505 	/*
506 	 * If we've already called start_color(), make sure all instances
507 	 * of the curses default colour pair are dirty.
508 	 */
509 	if (__using_color)
510 		__change_pair(PAIR_NUMBER(__default_color));
511 
512 	return(OK);
513 }
514 
515 /* no_color_video is a terminfo macro, but we need to retain binary compat */
516 #ifdef __strong_alias
517 #undef no_color_video
518 __strong_alias(no_color_video, no_color_attributes)
519 #endif
520 /*
521  * no_color_attributes --
522  *	Return attributes that cannot be combined with color.
523  */
524 attr_t
525 no_color_attributes(void)
526 {
527 	return(_cursesi_screen->nca);
528 }
529 
530 /*
531  * __set_color --
532  *	Set terminal foreground and background colours.
533  */
534 void
535 __set_color( /*ARGSUSED*/ WINDOW *win, attr_t attr)
536 {
537 	short	pair;
538 
539 	if ((curscr->wattr & __COLOR) == (attr & __COLOR))
540 		return;
541 
542 	pair = PAIR_NUMBER((uint32_t)attr);
543 #ifdef DEBUG
544 	__CTRACE(__CTRACE_COLOR, "__set_color: %d, %d, %d\n", pair,
545 		 _cursesi_screen->colour_pairs[pair].fore,
546 		 _cursesi_screen->colour_pairs[pair].back);
547 #endif
548 	switch (_cursesi_screen->color_type) {
549 	/* Set ANSI forground and background colours */
550 	case COLOR_ANSI:
551 		if (_cursesi_screen->colour_pairs[pair].fore < 0 ||
552 		    _cursesi_screen->colour_pairs[pair].back < 0)
553 			__unset_color(curscr);
554 		if (_cursesi_screen->colour_pairs[pair].fore >= 0)
555 			tputs(tiparm(t_set_a_foreground(_cursesi_screen->term),
556 			    (int)_cursesi_screen->colour_pairs[pair].fore),
557 			    0, __cputchar);
558 		if (_cursesi_screen->colour_pairs[pair].back >= 0)
559 			tputs(tiparm(t_set_a_background(_cursesi_screen->term),
560 			    (int)_cursesi_screen->colour_pairs[pair].back),
561 			    0, __cputchar);
562 		break;
563 	case COLOR_HP:
564 		/* XXX: need to support HP style */
565 		break;
566 	case COLOR_TEK:
567 		/* XXX: need to support Tek style */
568 		break;
569 	case COLOR_OTHER:
570 		if (_cursesi_screen->colour_pairs[pair].fore < 0 ||
571 		    _cursesi_screen->colour_pairs[pair].back < 0)
572 			__unset_color(curscr);
573 		if (_cursesi_screen->colour_pairs[pair].fore >= 0)
574 			tputs(tiparm(t_set_foreground(_cursesi_screen->term),
575 			    (int)_cursesi_screen->colour_pairs[pair].fore),
576 			    0, __cputchar);
577 		if (_cursesi_screen->colour_pairs[pair].back >= 0)
578 			tputs(tiparm(t_set_background(_cursesi_screen->term),
579 			    (int)_cursesi_screen->colour_pairs[pair].back),
580 			    0, __cputchar);
581 		break;
582 	}
583 	curscr->wattr &= ~__COLOR;
584 	curscr->wattr |= attr & __COLOR;
585 }
586 
587 /*
588  * __unset_color --
589  *	Clear terminal foreground and background colours.
590  */
591 void
592 __unset_color(WINDOW *win)
593 {
594 #ifdef DEBUG
595 	__CTRACE(__CTRACE_COLOR, "__unset_color\n");
596 #endif
597 	switch (_cursesi_screen->color_type) {
598 	/* Clear ANSI forground and background colours */
599 	case COLOR_ANSI:
600 		if (orig_pair != NULL) {
601 			tputs(orig_pair, 0, __cputchar);
602 			win->wattr &= __mask_op;
603 		}
604 		break;
605 	case COLOR_HP:
606 		/* XXX: need to support HP style */
607 		break;
608 	case COLOR_TEK:
609 		/* XXX: need to support Tek style */
610 		break;
611 	case COLOR_OTHER:
612 		if (orig_pair != NULL) {
613 			tputs(orig_pair, 0, __cputchar);
614 			win->wattr &= __mask_op;
615 		}
616 		break;
617 	}
618 }
619 
620 /*
621  * __restore_colors --
622  *	Redo color definitions after restarting 'curses' mode.
623  */
624 void
625 __restore_colors(void)
626 {
627 	if (can_change != 0)
628 		switch (_cursesi_screen->color_type) {
629 		case COLOR_HP:
630 			/* XXX: need to re-initialise HP style (Ip) */
631 			break;
632 		case COLOR_TEK:
633 			/* XXX: need to re-initialise Tek style (Ic) */
634 			break;
635 		}
636 }
637 
638 /*
639  * __change_pair --
640  *	Mark dirty all positions using pair.
641  */
642 void
643 __change_pair(short pair)
644 {
645 	struct __winlist	*wlp;
646 	WINDOW			*win;
647 	int			 y, x;
648 	__LINE			*lp;
649 	uint32_t		cl = COLOR_PAIR(pair);
650 
651 
652 	for (wlp = _cursesi_screen->winlistp; wlp != NULL; wlp = wlp->nextp) {
653 #ifdef DEBUG
654 		__CTRACE(__CTRACE_COLOR, "__change_pair: win = %p\n",
655 		    wlp->winp);
656 #endif
657 		win = wlp->winp;
658 		if (win == __virtscr)
659 			continue;
660 		else if (win == curscr) {
661 			/* Reset colour attribute on curscr */
662 #ifdef DEBUG
663 			__CTRACE(__CTRACE_COLOR,
664 			    "__change_pair: win == curscr\n");
665 #endif
666 			for (y = 0; y < curscr->maxy; y++) {
667 				lp = curscr->alines[y];
668 				for (x = 0; x < curscr->maxx; x++) {
669 					if ((lp->line[x].attr & __COLOR) == cl)
670 						lp->line[x].attr &= ~__COLOR;
671 				}
672 			}
673 		} else {
674 			/* Mark dirty those positions with colour pair "pair" */
675 			for (y = 0; y < win->maxy; y++) {
676 				lp = win->alines[y];
677 				for (x = 0; x < win->maxx; x++)
678 					if ((lp->line[x].attr &
679 					    __COLOR) == cl) {
680 						if (!(lp->flags & __ISDIRTY))
681 							lp->flags |= __ISDIRTY;
682 						/*
683 						 * firstchp/lastchp are shared
684 						 * between parent window and
685 						 * sub-window.
686 						 */
687 						if (*lp->firstchp > x)
688 							*lp->firstchp = x;
689 						if (*lp->lastchp < x)
690 							*lp->lastchp = x;
691 					}
692 #ifdef DEBUG
693 				if ((win->alines[y]->flags & __ISDIRTY))
694 					__CTRACE(__CTRACE_COLOR,
695 					    "__change_pair: first = %d, "
696 					    "last = %d\n",
697 					    *win->alines[y]->firstchp,
698 					    *win->alines[y]->lastchp);
699 #endif
700 			}
701 		}
702 	}
703 }
704