xref: /netbsd-src/lib/libcurses/color.c (revision fad4c9f71477ae11cea2ee75ec82151ac770a534)
1 /*	$NetBSD: color.c,v 1.30 2006/01/15 11:43:54 jdc 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  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *        This product includes software developed by the NetBSD
21  *        Foundation, Inc. and its contributors.
22  * 4. Neither the name of The NetBSD Foundation nor the names of its
23  *    contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36  * POSSIBILITY OF SUCH DAMAGE.
37  */
38 
39 #include <sys/cdefs.h>
40 #ifndef lint
41 __RCSID("$NetBSD: color.c,v 1.30 2006/01/15 11:43:54 jdc Exp $");
42 #endif				/* not lint */
43 
44 #include "curses.h"
45 #include "curses_private.h"
46 
47 /* Have we initialised colours? */
48 int	__using_color = 0;
49 
50 /* Default colour number */
51 attr_t	__default_color = 0;
52 
53 /* Default colour pair values - white on black. */
54 struct __pair	__default_pair = {COLOR_WHITE, COLOR_BLACK, 0};
55 
56 /* Default colour values */
57 /* Flags for colours and pairs */
58 #define	__USED		0x01
59 
60 static void
61 __change_pair(short);
62 
63 /*
64  * has_colors --
65  *	Check if terminal has colours.
66  */
67 bool
68 has_colors(void)
69 {
70 	if (__tc_Co > 0 && __tc_pa > 0 && ((__tc_AF != NULL &&
71 	    __tc_AB != NULL) || __tc_Ip != NULL || __tc_Ic != NULL ||
72 	    (__tc_Sb != NULL && __tc_Sf != NULL)))
73 		return(TRUE);
74 	else
75 		return(FALSE);
76 }
77 
78 /*
79  * can_change_color --
80  *	Check if terminal can change colours.
81  */
82 bool
83 can_change_color(void)
84 {
85 	if (__tc_cc)
86 		return(TRUE);
87 	else
88 		return(FALSE);
89 }
90 
91 /*
92  * start_color --
93  *	Initialise colour support.
94  */
95 int
96 start_color(void)
97 {
98 	int			 i;
99 	attr_t			 temp_nc;
100 	struct __winlist	*wlp;
101 	WINDOW			*win;
102 	int			 y, x;
103 
104 	if (has_colors() == FALSE)
105 		return(ERR);
106 
107 	/* Max colours and colour pairs */
108 	if (__tc_Co == -1)
109 		COLORS = 0;
110 	else {
111 		COLORS = __tc_Co > MAX_COLORS ? MAX_COLORS : __tc_Co;
112 		if (__tc_pa == -1) {
113 			COLOR_PAIRS = 0;
114 			COLORS = 0;
115 		} else {
116 			COLOR_PAIRS = (__tc_pa > MAX_PAIRS - 1 ?
117 			    MAX_PAIRS - 1 : __tc_pa);
118 			 /* Use the last colour pair for curses default. */
119 			__default_color = COLOR_PAIR(MAX_PAIRS - 1);
120 		}
121 	}
122 	if (!COLORS)
123 		return (ERR);
124 
125 	_cursesi_screen->COLORS = COLORS;
126 	_cursesi_screen->COLOR_PAIRS = COLOR_PAIRS;
127 
128 	/* Reset terminal colour and colour pairs. */
129 	if (__tc_oc != NULL)
130 		tputs(__tc_oc, 0, __cputchar);
131 	if (__tc_op != NULL) {
132 		tputs(__tc_op, 0, __cputchar);
133 		curscr->wattr &= _cursesi_screen->mask_op;
134 	}
135 
136 	/* Type of colour manipulation - ANSI/TEK/HP/other */
137 	if (__tc_AF != NULL && __tc_AB != NULL)
138 		_cursesi_screen->color_type = COLOR_ANSI;
139 	else if (__tc_Ip != NULL)
140 		_cursesi_screen->color_type = COLOR_HP;
141 	else if (__tc_Ic != NULL)
142 		_cursesi_screen->color_type = COLOR_TEK;
143 	else if (__tc_Sb != NULL && __tc_Sf != NULL)
144 		_cursesi_screen->color_type = COLOR_OTHER;
145 	else
146 		return(ERR);		/* Unsupported colour method */
147 
148 #ifdef DEBUG
149 	__CTRACE("start_color: COLORS = %d, COLOR_PAIRS = %d",
150 	    COLORS, COLOR_PAIRS);
151 	switch (_cursesi_screen->color_type) {
152 	case COLOR_ANSI:
153 		__CTRACE(" (ANSI style)\n");
154 		break;
155 	case COLOR_HP:
156 		__CTRACE(" (HP style)\n");
157 		break;
158 	case COLOR_TEK:
159 		__CTRACE(" (Tektronics style)\n");
160 		break;
161 	case COLOR_OTHER:
162 		__CTRACE(" (Other style)\n");
163 		break;
164 	}
165 #endif
166 
167 	/*
168 	 * Attributes that cannot be used with color.
169 	 * Store these in an attr_t for wattrset()/wattron().
170 	 */
171 	_cursesi_screen->nca = __NORMAL;
172 	if (__tc_NC != -1) {
173 		temp_nc = (attr_t) t_getnum(_cursesi_screen->cursesi_genbuf, "NC");
174 		if (temp_nc & 0x0001)
175 			_cursesi_screen->nca |= __STANDOUT;
176 		if (temp_nc & 0x0002)
177 			_cursesi_screen->nca |= __UNDERSCORE;
178 		if (temp_nc & 0x0004)
179 			_cursesi_screen->nca |= __REVERSE;
180 		if (temp_nc & 0x0008)
181 			_cursesi_screen->nca |= __BLINK;
182 		if (temp_nc & 0x0010)
183 			_cursesi_screen->nca |= __DIM;
184 		if (temp_nc & 0x0020)
185 			_cursesi_screen->nca |= __BOLD;
186 		if (temp_nc & 0x0040)
187 			_cursesi_screen->nca |= __BLANK;
188 		if (temp_nc & 0x0080)
189 			_cursesi_screen->nca |= __PROTECT;
190 		if (temp_nc & 0x0100)
191 			_cursesi_screen->nca |= __ALTCHARSET;
192 	}
193 #ifdef DEBUG
194 	__CTRACE ("start_color: _cursesi_screen->nca = %08x\n",
195 	    _cursesi_screen->nca);
196 #endif
197 
198 	/* Set up initial 8 colours */
199 	if (COLORS >= COLOR_BLACK)
200 		(void) init_color(COLOR_BLACK, 0, 0, 0);
201 	if (COLORS >= COLOR_RED)
202 		(void) init_color(COLOR_RED, 1000, 0, 0);
203 	if (COLORS >= COLOR_GREEN)
204 		(void) init_color(COLOR_GREEN, 0, 1000, 0);
205 	if (COLORS >= COLOR_YELLOW)
206 		(void) init_color(COLOR_YELLOW, 1000, 1000, 0);
207 	if (COLORS >= COLOR_BLUE)
208 		(void) init_color(COLOR_BLUE, 0, 0, 1000);
209 	if (COLORS >= COLOR_MAGENTA)
210 		(void) init_color(COLOR_MAGENTA, 1000, 0, 1000);
211 	if (COLORS >= COLOR_CYAN)
212 		(void) init_color(COLOR_CYAN, 0, 1000, 1000);
213 	if (COLORS >= COLOR_WHITE)
214 		(void) init_color(COLOR_WHITE, 1000, 1000, 1000);
215 
216 	/* Initialise other colours */
217 	for (i = 8; i < COLORS; i++) {
218 		_cursesi_screen->colours[i].red = 0;
219 		_cursesi_screen->colours[i].green = 0;
220 		_cursesi_screen->colours[i].blue = 0;
221 		_cursesi_screen->colours[i].flags = 0;
222 	}
223 
224 	/* Initialise pair 0 to default colours. */
225 	_cursesi_screen->colour_pairs[0].fore = -1;
226 	_cursesi_screen->colour_pairs[0].back = -1;
227 	_cursesi_screen->colour_pairs[0].flags = 0;
228 
229 	/* Initialise user colour pairs to default (white on black) */
230 	for (i = 0; i < COLOR_PAIRS; i++) {
231 		_cursesi_screen->colour_pairs[i].fore = COLOR_WHITE;
232 		_cursesi_screen->colour_pairs[i].back = COLOR_BLACK;
233 		_cursesi_screen->colour_pairs[i].flags = 0;
234 	}
235 
236 	/* Initialise default colour pair. */
237 	_cursesi_screen->colour_pairs[PAIR_NUMBER(__default_color)].fore =
238 	    __default_pair.fore;
239 	_cursesi_screen->colour_pairs[PAIR_NUMBER(__default_color)].back =
240 	    __default_pair.back;
241 	_cursesi_screen->colour_pairs[PAIR_NUMBER(__default_color)].flags =
242 	    __default_pair.flags;
243 
244 	__using_color = 1;
245 
246 	/* Set all positions on all windows to curses default colours. */
247 	for (wlp = _cursesi_screen->winlistp; wlp != NULL; wlp = wlp->nextp) {
248 		win = wlp->winp;
249 		if (wlp->winp != __virtscr && wlp->winp != curscr) {
250 			/* Set color attribute on other windows */
251 			win->battr |= __default_color;
252 			for (y = 0; y < win->maxy; y++) {
253 				for (x = 0; x < win->maxx; x++) {
254 					win->lines[y]->line[x].attr &= ~__COLOR;
255 					win->lines[y]->line[x].attr |= __default_color;
256 				}
257 			}
258 			__touchwin(win);
259 		}
260 	}
261 
262 	return(OK);
263 }
264 
265 /*
266  * init_pair --
267  *	Set pair foreground and background colors.
268  *	Our default colour ordering is ANSI - 1 = red, 4 = blue, 3 = yellow,
269  *	6 = cyan.  The older style (Sb/Sf) uses 1 = blue, 4 = red, 3 = cyan,
270  *	6 = yellow, so we swap them here and in pair_content().
271  */
272 int
273 init_pair(short pair, short fore, short back)
274 {
275 	int	changed;
276 
277 #ifdef DEBUG
278 	__CTRACE("init_pair: %d, %d, %d\n", pair, fore, back);
279 #endif
280 
281 	if (pair < 0 || pair >= COLOR_PAIRS)
282 		return (ERR);
283 	if (fore >= COLORS)
284 		return (ERR);
285 	if (back >= COLORS)
286 		return (ERR);
287 
288 	/* Swap red/blue and yellow/cyan */
289 	if (_cursesi_screen->color_type == COLOR_OTHER) {
290 		switch (fore) {
291 		case COLOR_RED:
292 			fore = COLOR_BLUE;
293 			break;
294 		case COLOR_BLUE:
295 			fore = COLOR_RED;
296 			break;
297 		case COLOR_YELLOW:
298 			fore = COLOR_CYAN;
299 			break;
300 		case COLOR_CYAN:
301 			fore = COLOR_YELLOW;
302 			break;
303 		}
304 		switch (back) {
305 		case COLOR_RED:
306 			back = COLOR_BLUE;
307 			break;
308 		case COLOR_BLUE:
309 			back = COLOR_RED;
310 			break;
311 		case COLOR_YELLOW:
312 			back = COLOR_CYAN;
313 			break;
314 		case COLOR_CYAN:
315 			back = COLOR_YELLOW;
316 			break;
317 		}
318 	}
319 
320 	if ((_cursesi_screen->colour_pairs[pair].flags & __USED) &&
321 	    (fore != _cursesi_screen->colour_pairs[pair].fore ||
322 	     back != _cursesi_screen->colour_pairs[pair].back))
323 		changed = 1;
324 	else
325 		changed = 0;
326 
327 	_cursesi_screen->colour_pairs[pair].flags |= __USED;
328 	_cursesi_screen->colour_pairs[pair].fore = fore;
329 	_cursesi_screen->colour_pairs[pair].back = back;
330 
331 	/* XXX: need to initialise HP style (Ip) */
332 
333 	if (changed)
334 		__change_pair(pair);
335 	return (OK);
336 }
337 
338 /*
339  * pair_content --
340  *	Get pair foreground and background colours.
341  */
342 int
343 pair_content(short pair, short *forep, short *backp)
344 {
345 	if (pair < 0 || pair > _cursesi_screen->COLOR_PAIRS)
346 		return(ERR);
347 
348 	*forep = _cursesi_screen->colour_pairs[pair].fore;
349 	*backp = _cursesi_screen->colour_pairs[pair].back;
350 
351 	/* Swap red/blue and yellow/cyan */
352 	if (_cursesi_screen->color_type == COLOR_OTHER) {
353 		switch (*forep) {
354 		case COLOR_RED:
355 			*forep = COLOR_BLUE;
356 			break;
357 		case COLOR_BLUE:
358 			*forep = COLOR_RED;
359 			break;
360 		case COLOR_YELLOW:
361 			*forep = COLOR_CYAN;
362 			break;
363 		case COLOR_CYAN:
364 			*forep = COLOR_YELLOW;
365 			break;
366 		}
367 		switch (*backp) {
368 		case COLOR_RED:
369 			*backp = COLOR_BLUE;
370 			break;
371 		case COLOR_BLUE:
372 			*backp = COLOR_RED;
373 			break;
374 		case COLOR_YELLOW:
375 			*backp = COLOR_CYAN;
376 			break;
377 		case COLOR_CYAN:
378 			*backp = COLOR_YELLOW;
379 			break;
380 		}
381 	}
382 	return(OK);
383 }
384 
385 /*
386  * init_color --
387  *	Set colour red, green and blue values.
388  */
389 int
390 init_color(short color, short red, short green, short blue)
391 {
392 #ifdef DEBUG
393 	__CTRACE("init_color: %d, %d, %d, %d\n", color, red, green, blue);
394 #endif
395 	if (color < 0 || color >= _cursesi_screen->COLORS)
396 		return(ERR);
397 
398 	_cursesi_screen->colours[color].red = red;
399 	_cursesi_screen->colours[color].green = green;
400 	_cursesi_screen->colours[color].blue = blue;
401 	/* XXX Not yet implemented */
402 	return(ERR);
403 	/* XXX: need to initialise Tek style (Ic) and support HLS */
404 }
405 
406 /*
407  * color_content --
408  *	Get colour red, green and blue values.
409  */
410 int
411 color_content(short color, short *redp, short *greenp, short *bluep)
412 {
413 	if (color < 0 || color >= _cursesi_screen->COLORS)
414 		return(ERR);
415 
416 	*redp = _cursesi_screen->colours[color].red;
417 	*greenp = _cursesi_screen->colours[color].green;
418 	*bluep = _cursesi_screen->colours[color].blue;
419 	return(OK);
420 }
421 
422 /*
423  * use_default_colors --
424  *	Use terminal default colours instead of curses default colour.
425   */
426 int
427 use_default_colors()
428 {
429 #ifdef DEBUG
430 	__CTRACE("use_default_colors\n");
431 #endif
432 
433 	return(assume_default_colors(-1, -1));
434 }
435 
436 /*
437  * assume_default_colors --
438  *	Set the default foreground and background colours.
439  */
440 int
441 assume_default_colors(short fore, short back)
442 {
443 #ifdef DEBUG
444 	__CTRACE("assume_default_colors: %d, %d\n", fore, back);
445 #endif
446 	/* Swap red/blue and yellow/cyan */
447 	if (_cursesi_screen->color_type == COLOR_OTHER) {
448 		switch (fore) {
449 		case COLOR_RED:
450 			fore = COLOR_BLUE;
451 			break;
452 		case COLOR_BLUE:
453 			fore = COLOR_RED;
454 			break;
455 		case COLOR_YELLOW:
456 			fore = COLOR_CYAN;
457 			break;
458 		case COLOR_CYAN:
459 			fore = COLOR_YELLOW;
460 			break;
461 		}
462 		switch (back) {
463 		case COLOR_RED:
464 			back = COLOR_BLUE;
465 			break;
466 		case COLOR_BLUE:
467 			back = COLOR_RED;
468 			break;
469 		case COLOR_YELLOW:
470 			back = COLOR_CYAN;
471 			break;
472 		case COLOR_CYAN:
473 			back = COLOR_YELLOW;
474 			break;
475 		}
476 	}
477 	__default_pair.fore = fore;
478 	__default_pair.back = back;
479 	__default_pair.flags = __USED;
480 
481 	if (COLOR_PAIRS) {
482 		_cursesi_screen->colour_pairs[PAIR_NUMBER(__default_color)].fore = fore;
483 		_cursesi_screen->colour_pairs[PAIR_NUMBER(__default_color)].back = back;
484 		_cursesi_screen->colour_pairs[PAIR_NUMBER(__default_color)].flags = __USED;
485 	}
486 
487 	/*
488 	 * If we've already called start_color(), make sure all instances
489 	 * of the curses default colour pair are dirty.
490 	 */
491 	if (__using_color)
492 		__change_pair(PAIR_NUMBER(__default_color));
493 
494 	return(OK);
495 }
496 
497 /*
498  * no_color_video --
499  *	Return attributes that cannot be combined with color.
500  */
501 attr_t
502 no_color_video(void)
503 {
504 	return(_cursesi_screen->nca);
505 }
506 
507 /*
508  * __set_color --
509  *	Set terminal foreground and background colours.
510  */
511 void
512 __set_color( /*ARGSUSED*/ WINDOW *win, attr_t attr)
513 {
514 	short	pair;
515 
516 	if ((curscr->wattr & __COLOR) == (attr & __COLOR))
517 		return;
518 
519 	pair = PAIR_NUMBER((u_int32_t)attr);
520 #ifdef DEBUG
521 	__CTRACE("__set_color: %d, %d, %d\n", pair,
522 		 _cursesi_screen->colour_pairs[pair].fore,
523 		 _cursesi_screen->colour_pairs[pair].back);
524 #endif
525 	switch (_cursesi_screen->color_type) {
526 	/* Set ANSI forground and background colours */
527 	case COLOR_ANSI:
528 		if (_cursesi_screen->colour_pairs[pair].fore < 0 ||
529 		    _cursesi_screen->colour_pairs[pair].back < 0)
530 			__unset_color(curscr);
531 		if (_cursesi_screen->colour_pairs[pair].fore >= 0)
532 			tputs(__parse_cap(_cursesi_screen->tc_AF,
533 			    _cursesi_screen->colour_pairs[pair].fore),
534 			    0, __cputchar);
535 		if (_cursesi_screen->colour_pairs[pair].back >= 0)
536 			tputs(__parse_cap(_cursesi_screen->tc_AB,
537 			    _cursesi_screen->colour_pairs[pair].back),
538 			    0, __cputchar);
539 		break;
540 	case COLOR_HP:
541 		/* XXX: need to support HP style */
542 		break;
543 	case COLOR_TEK:
544 		/* XXX: need to support Tek style */
545 		break;
546 	case COLOR_OTHER:
547 		if (_cursesi_screen->colour_pairs[pair].fore < 0 ||
548 		    _cursesi_screen->colour_pairs[pair].back < 0)
549 			__unset_color(curscr);
550 		if (_cursesi_screen->colour_pairs[pair].fore >= 0)
551 			tputs(__parse_cap(_cursesi_screen->tc_Sf,
552 			    _cursesi_screen->colour_pairs[pair].fore),
553 			    0, __cputchar);
554 		if (_cursesi_screen->colour_pairs[pair].back >= 0)
555 			tputs(__parse_cap(_cursesi_screen->tc_Sb,
556 			    _cursesi_screen->colour_pairs[pair].back),
557 			    0, __cputchar);
558 		break;
559 	}
560 	curscr->wattr &= ~__COLOR;
561 	curscr->wattr |= attr & __COLOR;
562 }
563 
564 /*
565  * __unset_color --
566  *	Clear terminal foreground and background colours.
567  */
568 void
569 __unset_color(WINDOW *win)
570 {
571 #ifdef DEBUG
572 	__CTRACE("__unset_color\n");
573 #endif
574 	switch (_cursesi_screen->color_type) {
575 	/* Clear ANSI forground and background colours */
576 	case COLOR_ANSI:
577 		if (__tc_op != NULL) {
578 			tputs(__tc_op, 0, __cputchar);
579 			win->wattr &= __mask_op;
580 		}
581 		break;
582 	case COLOR_HP:
583 		/* XXX: need to support HP style */
584 		break;
585 	case COLOR_TEK:
586 		/* XXX: need to support Tek style */
587 		break;
588 	case COLOR_OTHER:
589 		if (__tc_op != NULL) {
590 			tputs(__tc_op, 0, __cputchar);
591 			win->wattr &= __mask_op;
592 		}
593 		break;
594 	}
595 }
596 
597 /*
598  * __restore_colors --
599  *	Redo color definitions after restarting 'curses' mode.
600  */
601 void
602 __restore_colors(void)
603 {
604 	if (__tc_cc != 0)
605 		switch (_cursesi_screen->color_type) {
606 		case COLOR_HP:
607 			/* XXX: need to re-initialise HP style (Ip) */
608 			break;
609 		case COLOR_TEK:
610 			/* XXX: need to re-initialise Tek style (Ic) */
611 			break;
612 		}
613 }
614 
615 /*
616  * __change_pair --
617  *	Mark dirty all positions using pair.
618  */
619 void
620 __change_pair(short pair)
621 {
622 	struct __winlist	*wlp;
623 	WINDOW			*win;
624 	int			 y, x;
625 	__LINE			*lp;
626 	uint32_t		cl = COLOR_PAIR(pair);
627 
628 
629 	for (wlp = _cursesi_screen->winlistp; wlp != NULL; wlp = wlp->nextp) {
630 #ifdef DEBUG
631 		__CTRACE("__change_pair: win = %p\n", wlp->winp);
632 #endif
633 		win = wlp->winp;
634 		if (win == __virtscr)
635 			continue;
636 		else if (win == curscr) {
637 			/* Reset colour attribute on curscr */
638 #ifdef DEBUG
639 			__CTRACE("__change_pair: win == curscr\n");
640 #endif
641 			for (y = 0; y < curscr->maxy; y++) {
642 				lp = curscr->lines[y];
643 				for (x = 0; x < curscr->maxx; x++) {
644 					if ((lp->line[x].attr & __COLOR) == cl)
645 						lp->line[x].attr &= ~__COLOR;
646 				}
647 			}
648 		} else {
649 			/* Mark dirty those positions with colour pair "pair" */
650 			for (y = 0; y < win->maxy; y++) {
651 				lp = curscr->lines[y];
652 				for (x = 0; x < win->maxx; x++)
653 					if ((lp->line[x].attr &
654 					    __COLOR) == cl) {
655 						if (!(lp->flags & __ISDIRTY))
656 							lp->flags |= __ISDIRTY;
657 						/*
658 					 	* firstchp/lastchp are shared
659 					 	* between parent window and
660 					 	* sub-window.
661 					 	*/
662 						if (*lp->firstchp > x)
663 						*lp->firstchp = x;
664 						if (*lp->lastchp < x)
665 							*lp->lastchp = x;
666 					}
667 #ifdef DEBUG
668 				if ((win->lines[y]->flags & __ISDIRTY))
669 					__CTRACE("__change_pair: first = %d, last = %d\n", *win->lines[y]->firstchp, *win->lines[y]->lastchp);
670 #endif
671 			}
672 		}
673 	}
674 }
675