xref: /netbsd-src/lib/libcurses/color.c (revision 4817a0b0b8fe9612e8ebe21a9bf2d97b95038a97)
1 /*	$NetBSD: color.c,v 1.36 2010/12/25 10:05:08 blymn 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 1.36 2010/12/25 10:05:08 blymn 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 /*
57  * has_colors --
58  *	Check if terminal has colours.
59  */
60 bool
61 has_colors(void)
62 {
63 	if (max_colors > 0 && max_pairs > 0 &&
64 	    ((set_a_foreground != NULL && set_a_background != NULL) ||
65 		initialize_pair != NULL || initialize_color != NULL ||
66 		(set_background != NULL && set_foreground != NULL)))
67 		return(TRUE);
68 	else
69 		return(FALSE);
70 }
71 
72 /*
73  * can_change_color --
74  *	Check if terminal can change colours.
75  */
76 bool
77 can_change_color(void)
78 {
79 	if (can_change)
80 		return(TRUE);
81 	else
82 		return(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 	if (COLORS >= COLOR_BLACK)
194 		(void) init_color(COLOR_BLACK, 0, 0, 0);
195 	if (COLORS >= COLOR_RED)
196 		(void) init_color(COLOR_RED, 1000, 0, 0);
197 	if (COLORS >= COLOR_GREEN)
198 		(void) init_color(COLOR_GREEN, 0, 1000, 0);
199 	if (COLORS >= COLOR_YELLOW)
200 		(void) init_color(COLOR_YELLOW, 1000, 1000, 0);
201 	if (COLORS >= COLOR_BLUE)
202 		(void) init_color(COLOR_BLUE, 0, 0, 1000);
203 	if (COLORS >= COLOR_MAGENTA)
204 		(void) init_color(COLOR_MAGENTA, 1000, 0, 1000);
205 	if (COLORS >= COLOR_CYAN)
206 		(void) init_color(COLOR_CYAN, 0, 1000, 1000);
207 	if (COLORS >= COLOR_WHITE)
208 		(void) init_color(COLOR_WHITE, 1000, 1000, 1000);
209 
210 	/* Initialise other colours */
211 	for (i = 8; i < COLORS; i++) {
212 		_cursesi_screen->colours[i].red = 0;
213 		_cursesi_screen->colours[i].green = 0;
214 		_cursesi_screen->colours[i].blue = 0;
215 		_cursesi_screen->colours[i].flags = 0;
216 	}
217 
218 	/* Initialise pair 0 to default colours. */
219 	_cursesi_screen->colour_pairs[0].fore = -1;
220 	_cursesi_screen->colour_pairs[0].back = -1;
221 	_cursesi_screen->colour_pairs[0].flags = 0;
222 
223 	/* Initialise user colour pairs to default (white on black) */
224 	for (i = 0; i < COLOR_PAIRS; i++) {
225 		_cursesi_screen->colour_pairs[i].fore = COLOR_WHITE;
226 		_cursesi_screen->colour_pairs[i].back = COLOR_BLACK;
227 		_cursesi_screen->colour_pairs[i].flags = 0;
228 	}
229 
230 	/* Initialise default colour pair. */
231 	_cursesi_screen->colour_pairs[PAIR_NUMBER(__default_color)].fore =
232 	    __default_pair.fore;
233 	_cursesi_screen->colour_pairs[PAIR_NUMBER(__default_color)].back =
234 	    __default_pair.back;
235 	_cursesi_screen->colour_pairs[PAIR_NUMBER(__default_color)].flags =
236 	    __default_pair.flags;
237 
238 	__using_color = 1;
239 
240 	/* Set all positions on all windows to curses default colours. */
241 	for (wlp = _cursesi_screen->winlistp; wlp != NULL; wlp = wlp->nextp) {
242 		win = wlp->winp;
243 		if (wlp->winp != __virtscr && wlp->winp != curscr) {
244 			/* Set color attribute on other windows */
245 			win->battr |= __default_color;
246 			for (y = 0; y < win->maxy; y++) {
247 				for (x = 0; x < win->maxx; x++) {
248 					win->alines[y]->line[x].attr &= ~__COLOR;
249 					win->alines[y]->line[x].attr |= __default_color;
250 				}
251 			}
252 			__touchwin(win);
253 		}
254 	}
255 
256 	return(OK);
257 }
258 
259 /*
260  * init_pair --
261  *	Set pair foreground and background colors.
262  *	Our default colour ordering is ANSI - 1 = red, 4 = blue, 3 = yellow,
263  *	6 = cyan.  The older style (Sb/Sf) uses 1 = blue, 4 = red, 3 = cyan,
264  *	6 = yellow, so we swap them here and in pair_content().
265  */
266 int
267 init_pair(short pair, short fore, short back)
268 {
269 	int	changed;
270 
271 #ifdef DEBUG
272 	__CTRACE(__CTRACE_COLOR, "init_pair: %d, %d, %d\n", pair, fore, back);
273 #endif
274 
275 	if (pair < 0 || pair >= COLOR_PAIRS)
276 		return (ERR);
277 
278 	if (pair == 0) /* Ignore request for pair 0, it is default. */
279 		return OK;
280 
281 	if (fore >= COLORS)
282 		return (ERR);
283 	if (back >= COLORS)
284 		return (ERR);
285 
286 	/* Swap red/blue and yellow/cyan */
287 	if (_cursesi_screen->color_type == COLOR_OTHER) {
288 		switch (fore) {
289 		case COLOR_RED:
290 			fore = COLOR_BLUE;
291 			break;
292 		case COLOR_BLUE:
293 			fore = COLOR_RED;
294 			break;
295 		case COLOR_YELLOW:
296 			fore = COLOR_CYAN;
297 			break;
298 		case COLOR_CYAN:
299 			fore = COLOR_YELLOW;
300 			break;
301 		}
302 		switch (back) {
303 		case COLOR_RED:
304 			back = COLOR_BLUE;
305 			break;
306 		case COLOR_BLUE:
307 			back = COLOR_RED;
308 			break;
309 		case COLOR_YELLOW:
310 			back = COLOR_CYAN;
311 			break;
312 		case COLOR_CYAN:
313 			back = COLOR_YELLOW;
314 			break;
315 		}
316 	}
317 
318 	if ((_cursesi_screen->colour_pairs[pair].flags & __USED) &&
319 	    (fore != _cursesi_screen->colour_pairs[pair].fore ||
320 	     back != _cursesi_screen->colour_pairs[pair].back))
321 		changed = 1;
322 	else
323 		changed = 0;
324 
325 	_cursesi_screen->colour_pairs[pair].flags |= __USED;
326 	_cursesi_screen->colour_pairs[pair].fore = fore;
327 	_cursesi_screen->colour_pairs[pair].back = back;
328 
329 	/* XXX: need to initialise HP style (Ip) */
330 
331 	if (changed)
332 		__change_pair(pair);
333 	return (OK);
334 }
335 
336 /*
337  * pair_content --
338  *	Get pair foreground and background colours.
339  */
340 int
341 pair_content(short pair, short *forep, short *backp)
342 {
343 	if (pair < 0 || pair > _cursesi_screen->COLOR_PAIRS)
344 		return(ERR);
345 
346 	*forep = _cursesi_screen->colour_pairs[pair].fore;
347 	*backp = _cursesi_screen->colour_pairs[pair].back;
348 
349 	/* Swap red/blue and yellow/cyan */
350 	if (_cursesi_screen->color_type == COLOR_OTHER) {
351 		switch (*forep) {
352 		case COLOR_RED:
353 			*forep = COLOR_BLUE;
354 			break;
355 		case COLOR_BLUE:
356 			*forep = COLOR_RED;
357 			break;
358 		case COLOR_YELLOW:
359 			*forep = COLOR_CYAN;
360 			break;
361 		case COLOR_CYAN:
362 			*forep = COLOR_YELLOW;
363 			break;
364 		}
365 		switch (*backp) {
366 		case COLOR_RED:
367 			*backp = COLOR_BLUE;
368 			break;
369 		case COLOR_BLUE:
370 			*backp = COLOR_RED;
371 			break;
372 		case COLOR_YELLOW:
373 			*backp = COLOR_CYAN;
374 			break;
375 		case COLOR_CYAN:
376 			*backp = COLOR_YELLOW;
377 			break;
378 		}
379 	}
380 	return(OK);
381 }
382 
383 /*
384  * init_color --
385  *	Set colour red, green and blue values.
386  */
387 int
388 init_color(short color, short red, short green, short blue)
389 {
390 #ifdef DEBUG
391 	__CTRACE(__CTRACE_COLOR, "init_color: %d, %d, %d, %d\n",
392 	    color, red, green, blue);
393 #endif
394 	if (color < 0 || color >= _cursesi_screen->COLORS)
395 		return(ERR);
396 
397 	_cursesi_screen->colours[color].red = red;
398 	_cursesi_screen->colours[color].green = green;
399 	_cursesi_screen->colours[color].blue = blue;
400 	/* XXX Not yet implemented */
401 	return(ERR);
402 	/* XXX: need to initialise Tek style (Ic) and support HLS */
403 }
404 
405 /*
406  * color_content --
407  *	Get colour red, green and blue values.
408  */
409 int
410 color_content(short color, short *redp, short *greenp, short *bluep)
411 {
412 	if (color < 0 || color >= _cursesi_screen->COLORS)
413 		return(ERR);
414 
415 	*redp = _cursesi_screen->colours[color].red;
416 	*greenp = _cursesi_screen->colours[color].green;
417 	*bluep = _cursesi_screen->colours[color].blue;
418 	return(OK);
419 }
420 
421 /*
422  * use_default_colors --
423  *	Use terminal default colours instead of curses default colour.
424   */
425 int
426 use_default_colors()
427 {
428 #ifdef DEBUG
429 	__CTRACE(__CTRACE_COLOR, "use_default_colors\n");
430 #endif
431 
432 	return(assume_default_colors(-1, -1));
433 }
434 
435 /*
436  * assume_default_colors --
437  *	Set the default foreground and background colours.
438  */
439 int
440 assume_default_colors(short arg_fore, short arg_back)
441 {
442 	short fore, back;
443 
444 	fore = arg_fore;
445 	back = arg_back;
446 
447 #ifdef DEBUG
448 	__CTRACE(__CTRACE_COLOR, "assume_default_colors: %d, %d\n",
449 	    fore, back);
450 	__CTRACE(__CTRACE_COLOR, "assume_default_colors: default_colour = %d, pair_number = %d\n", __default_color, PAIR_NUMBER(__default_color));
451 #endif
452 
453 	if (arg_fore == -1)
454 		fore = COLOR_WHITE;
455 	if (arg_back == -1)
456 		back = COLOR_BLACK;
457 
458 	/* Swap red/blue and yellow/cyan */
459 	if (_cursesi_screen->color_type == COLOR_OTHER) {
460 		switch (fore) {
461 		case COLOR_RED:
462 			fore = COLOR_BLUE;
463 			break;
464 		case COLOR_BLUE:
465 			fore = COLOR_RED;
466 			break;
467 		case COLOR_YELLOW:
468 			fore = COLOR_CYAN;
469 			break;
470 		case COLOR_CYAN:
471 			fore = COLOR_YELLOW;
472 			break;
473 		}
474 		switch (back) {
475 		case COLOR_RED:
476 			back = COLOR_BLUE;
477 			break;
478 		case COLOR_BLUE:
479 			back = COLOR_RED;
480 			break;
481 		case COLOR_YELLOW:
482 			back = COLOR_CYAN;
483 			break;
484 		case COLOR_CYAN:
485 			back = COLOR_YELLOW;
486 			break;
487 		}
488 	}
489 	__default_pair.fore = fore;
490 	__default_pair.back = back;
491 	__default_pair.flags = __USED;
492 
493 	if (COLOR_PAIRS) {
494 		_cursesi_screen->colour_pairs[PAIR_NUMBER(__default_color)].fore = fore;
495 		_cursesi_screen->colour_pairs[PAIR_NUMBER(__default_color)].back = back;
496 		_cursesi_screen->colour_pairs[PAIR_NUMBER(__default_color)].flags = __USED;
497 	}
498 
499 	/*
500 	 * If we've already called start_color(), make sure all instances
501 	 * of the curses default colour pair are dirty.
502 	 */
503 	if (__using_color)
504 		__change_pair(PAIR_NUMBER(__default_color));
505 
506 	return(OK);
507 }
508 
509 /* no_color_video is a terminfo macro, but we need to retain binary compat */
510 #ifdef __strong_alias
511 #undef no_color_video
512 __strong_alias(no_color_video, no_color_attributes)
513 #endif
514 /*
515  * no_color_attributes --
516  *	Return attributes that cannot be combined with color.
517  */
518 attr_t
519 no_color_attributes(void)
520 {
521 	return(_cursesi_screen->nca);
522 }
523 
524 /*
525  * __set_color --
526  *	Set terminal foreground and background colours.
527  */
528 void
529 __set_color( /*ARGSUSED*/ WINDOW *win, attr_t attr)
530 {
531 	short	pair;
532 
533 	if ((curscr->wattr & __COLOR) == (attr & __COLOR))
534 		return;
535 
536 	pair = PAIR_NUMBER((u_int32_t)attr);
537 #ifdef DEBUG
538 	__CTRACE(__CTRACE_COLOR, "__set_color: %d, %d, %d\n", pair,
539 		 _cursesi_screen->colour_pairs[pair].fore,
540 		 _cursesi_screen->colour_pairs[pair].back);
541 #endif
542 	switch (_cursesi_screen->color_type) {
543 	/* Set ANSI forground and background colours */
544 	case COLOR_ANSI:
545 		if (_cursesi_screen->colour_pairs[pair].fore < 0 ||
546 		    _cursesi_screen->colour_pairs[pair].back < 0)
547 			__unset_color(curscr);
548 		if (_cursesi_screen->colour_pairs[pair].fore >= 0)
549 			tputs(vtparm(t_set_a_foreground(_cursesi_screen->term),
550 			    _cursesi_screen->colour_pairs[pair].fore),
551 			    0, __cputchar);
552 		if (_cursesi_screen->colour_pairs[pair].back >= 0)
553 			tputs(vtparm(t_set_a_background(_cursesi_screen->term),
554 			    _cursesi_screen->colour_pairs[pair].back),
555 			    0, __cputchar);
556 		break;
557 	case COLOR_HP:
558 		/* XXX: need to support HP style */
559 		break;
560 	case COLOR_TEK:
561 		/* XXX: need to support Tek style */
562 		break;
563 	case COLOR_OTHER:
564 		if (_cursesi_screen->colour_pairs[pair].fore < 0 ||
565 		    _cursesi_screen->colour_pairs[pair].back < 0)
566 			__unset_color(curscr);
567 		if (_cursesi_screen->colour_pairs[pair].fore >= 0)
568 			tputs(vtparm(t_set_foreground(_cursesi_screen->term),
569 			    _cursesi_screen->colour_pairs[pair].fore),
570 			    0, __cputchar);
571 		if (_cursesi_screen->colour_pairs[pair].back >= 0)
572 			tputs(vtparm(t_set_background(_cursesi_screen->term),
573 			    _cursesi_screen->colour_pairs[pair].back),
574 			    0, __cputchar);
575 		break;
576 	}
577 	curscr->wattr &= ~__COLOR;
578 	curscr->wattr |= attr & __COLOR;
579 }
580 
581 /*
582  * __unset_color --
583  *	Clear terminal foreground and background colours.
584  */
585 void
586 __unset_color(WINDOW *win)
587 {
588 #ifdef DEBUG
589 	__CTRACE(__CTRACE_COLOR, "__unset_color\n");
590 #endif
591 	switch (_cursesi_screen->color_type) {
592 	/* Clear ANSI forground and background colours */
593 	case COLOR_ANSI:
594 		if (orig_pair != NULL) {
595 			tputs(orig_pair, 0, __cputchar);
596 			win->wattr &= __mask_op;
597 		}
598 		break;
599 	case COLOR_HP:
600 		/* XXX: need to support HP style */
601 		break;
602 	case COLOR_TEK:
603 		/* XXX: need to support Tek style */
604 		break;
605 	case COLOR_OTHER:
606 		if (orig_pair != NULL) {
607 			tputs(orig_pair, 0, __cputchar);
608 			win->wattr &= __mask_op;
609 		}
610 		break;
611 	}
612 }
613 
614 /*
615  * __restore_colors --
616  *	Redo color definitions after restarting 'curses' mode.
617  */
618 void
619 __restore_colors(void)
620 {
621 	if (can_change != 0)
622 		switch (_cursesi_screen->color_type) {
623 		case COLOR_HP:
624 			/* XXX: need to re-initialise HP style (Ip) */
625 			break;
626 		case COLOR_TEK:
627 			/* XXX: need to re-initialise Tek style (Ic) */
628 			break;
629 		}
630 }
631 
632 /*
633  * __change_pair --
634  *	Mark dirty all positions using pair.
635  */
636 void
637 __change_pair(short pair)
638 {
639 	struct __winlist	*wlp;
640 	WINDOW			*win;
641 	int			 y, x;
642 	__LINE			*lp;
643 	uint32_t		cl = COLOR_PAIR(pair);
644 
645 
646 	for (wlp = _cursesi_screen->winlistp; wlp != NULL; wlp = wlp->nextp) {
647 #ifdef DEBUG
648 		__CTRACE(__CTRACE_COLOR, "__change_pair: win = %p\n",
649 		    wlp->winp);
650 #endif
651 		win = wlp->winp;
652 		if (win == __virtscr)
653 			continue;
654 		else if (win == curscr) {
655 			/* Reset colour attribute on curscr */
656 #ifdef DEBUG
657 			__CTRACE(__CTRACE_COLOR,
658 			    "__change_pair: win == curscr\n");
659 #endif
660 			for (y = 0; y < curscr->maxy; y++) {
661 				lp = curscr->alines[y];
662 				for (x = 0; x < curscr->maxx; x++) {
663 					if ((lp->line[x].attr & __COLOR) == cl)
664 						lp->line[x].attr &= ~__COLOR;
665 				}
666 			}
667 		} else {
668 			/* Mark dirty those positions with colour pair "pair" */
669 			for (y = 0; y < win->maxy; y++) {
670 				lp = win->alines[y];
671 				for (x = 0; x < win->maxx; x++)
672 					if ((lp->line[x].attr &
673 					    __COLOR) == cl) {
674 						if (!(lp->flags & __ISDIRTY))
675 							lp->flags |= __ISDIRTY;
676 						/*
677 					 	* firstchp/lastchp are shared
678 					 	* between parent window and
679 					 	* sub-window.
680 					 	*/
681 						if (*lp->firstchp > x)
682 						*lp->firstchp = x;
683 						if (*lp->lastchp < x)
684 							*lp->lastchp = x;
685 					}
686 #ifdef DEBUG
687 				if ((win->alines[y]->flags & __ISDIRTY))
688 					__CTRACE(__CTRACE_COLOR,
689 					    "__change_pair: first = %d, "
690 					    "last = %d\n",
691 					    *win->alines[y]->firstchp,
692 					    *win->alines[y]->lastchp);
693 #endif
694 			}
695 		}
696 	}
697 }
698