1 /****************************************************************************
2  * Copyright 2018-2019,2020 Thomas E. Dickey                                *
3  * Copyright 1998-2016,2017 Free Software Foundation, Inc.                  *
4  *                                                                          *
5  * Permission is hereby granted, free of charge, to any person obtaining a  *
6  * copy of this software and associated documentation files (the            *
7  * "Software"), to deal in the Software without restriction, including      *
8  * without limitation the rights to use, copy, modify, merge, publish,      *
9  * distribute, distribute with modifications, sublicense, and/or sell       *
10  * copies of the Software, and to permit persons to whom the Software is    *
11  * furnished to do so, subject to the following conditions:                 *
12  *                                                                          *
13  * The above copyright notice and this permission notice shall be included  *
14  * in all copies or substantial portions of the Software.                   *
15  *                                                                          *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS  *
17  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF               *
18  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.   *
19  * IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,   *
20  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR    *
21  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR    *
22  * THE USE OR OTHER DEALINGS IN THE SOFTWARE.                               *
23  *                                                                          *
24  * Except as contained in this notice, the name(s) of the above copyright   *
25  * holders shall not be used in advertising or otherwise to promote the     *
26  * sale, use or other dealings in this Software without prior written       *
27  * authorization.                                                           *
28  ****************************************************************************/
29 
30 /****************************************************************************
31  *  Author: Zeyd M. Ben-Halim <zmbenhal@netcom.com> 1992,1995               *
32  *     and: Eric S. Raymond <esr@snark.thyrsus.com>                         *
33  *     and: Thomas E. Dickey                        1996-on                 *
34  *     and: Juergen Pfeifer                         2009                    *
35  ****************************************************************************/
36 
37 /* lib_color.c
38  *
39  * Handles color emulation of SYS V curses
40  */
41 
42 #define NEW_PAIR_INTERNAL 1
43 
44 #include <curses.priv.h>
45 #include <new_pair.h>
46 #include <tic.h>
47 
48 #ifndef CUR
49 #define CUR SP_TERMTYPE
50 #endif
51 
52 MODULE_ID("$Id: lib_color.c,v 1.143 2020/02/02 23:34:34 tom Exp $")
53 
54 #ifdef USE_TERM_DRIVER
55 #define CanChange      InfoOf(SP_PARM).canchange
56 #define DefaultPalette InfoOf(SP_PARM).defaultPalette
57 #define HasColor       InfoOf(SP_PARM).hascolor
58 #define InitColor      InfoOf(SP_PARM).initcolor
59 #define MaxColors      InfoOf(SP_PARM).maxcolors
60 #define MaxPairs       InfoOf(SP_PARM).maxpairs
61 #define UseHlsPalette  (DefaultPalette == _nc_hls_palette)
62 #else
63 #define CanChange      can_change
64 #define DefaultPalette (hue_lightness_saturation ? hls_palette : cga_palette)
65 #define HasColor       has_color
66 #define InitColor      initialize_color
67 #define MaxColors      max_colors
68 #define MaxPairs       max_pairs
69 #define UseHlsPalette  (hue_lightness_saturation)
70 #endif
71 
72 #ifndef USE_TERM_DRIVER
73 /*
74  * These should be screen structure members.  They need to be globals for
75  * historical reasons.  So we assign them in start_color() and also in
76  * set_term()'s screen-switching logic.
77  */
78 #if USE_REENTRANT
79 NCURSES_EXPORT(int)
80 NCURSES_PUBLIC_VAR(COLOR_PAIRS) (void)
81 {
82     return SP ? SP->_pair_count : -1;
83 }
84 NCURSES_EXPORT(int)
85 NCURSES_PUBLIC_VAR(COLORS) (void)
86 {
87     return SP ? SP->_color_count : -1;
88 }
89 #else
90 NCURSES_EXPORT_VAR(int) COLOR_PAIRS = 0;
91 NCURSES_EXPORT_VAR(int) COLORS = 0;
92 #endif
93 #endif /* !USE_TERM_DRIVER */
94 
95 #define DATA(r,g,b) {r,g,b, 0,0,0, 0}
96 
97 #define TYPE_CALLOC(type,elts) typeCalloc(type, (unsigned)(elts))
98 
99 #define MAX_PALETTE	8
100 
101 #define OkColorHi(n)	(((n) < COLORS) && ((n) < maxcolors))
102 #define InPalette(n)	((n) >= 0 && (n) < MAX_PALETTE)
103 
104 /*
105  * Given a RGB range of 0..1000, we'll normally set the individual values
106  * to about 2/3 of the maximum, leaving full-range for bold/bright colors.
107  */
108 #define RGB_ON  680
109 #define RGB_OFF 0
110 /* *INDENT-OFF* */
111 static const color_t cga_palette[] =
112 {
113     /*  R               G               B */
114     DATA(RGB_OFF,	RGB_OFF,	RGB_OFF),	/* COLOR_BLACK */
115     DATA(RGB_ON,	RGB_OFF,	RGB_OFF),	/* COLOR_RED */
116     DATA(RGB_OFF,	RGB_ON,		RGB_OFF),	/* COLOR_GREEN */
117     DATA(RGB_ON,	RGB_ON,		RGB_OFF),	/* COLOR_YELLOW */
118     DATA(RGB_OFF,	RGB_OFF,	RGB_ON),	/* COLOR_BLUE */
119     DATA(RGB_ON,	RGB_OFF,	RGB_ON),	/* COLOR_MAGENTA */
120     DATA(RGB_OFF,	RGB_ON,		RGB_ON),	/* COLOR_CYAN */
121     DATA(RGB_ON,	RGB_ON,		RGB_ON),	/* COLOR_WHITE */
122 };
123 
124 static const color_t hls_palette[] =
125 {
126     /*  	H       L       S */
127     DATA(	0,	0,	0),		/* COLOR_BLACK */
128     DATA(	120,	50,	100),		/* COLOR_RED */
129     DATA(	240,	50,	100),		/* COLOR_GREEN */
130     DATA(	180,	50,	100),		/* COLOR_YELLOW */
131     DATA(	330,	50,	100),		/* COLOR_BLUE */
132     DATA(	60,	50,	100),		/* COLOR_MAGENTA */
133     DATA(	300,	50,	100),		/* COLOR_CYAN */
134     DATA(	0,	50,	100),		/* COLOR_WHITE */
135 };
136 
137 #ifdef USE_TERM_DRIVER
138 NCURSES_EXPORT_VAR(const color_t*) _nc_cga_palette = cga_palette;
139 NCURSES_EXPORT_VAR(const color_t*) _nc_hls_palette = hls_palette;
140 #endif
141 
142 /* *INDENT-ON* */
143 
144 #if NCURSES_EXT_FUNCS
145 /*
146  * These are called from _nc_do_color(), which in turn is called from
147  * vidattr - so we have to assume that sp may be null.
148  */
149 static int
150 default_fg(NCURSES_SP_DCL0)
151 {
152     return (SP_PARM != 0) ? SP_PARM->_default_fg : COLOR_WHITE;
153 }
154 
155 static int
156 default_bg(NCURSES_SP_DCL0)
157 {
158     return SP_PARM != 0 ? SP_PARM->_default_bg : COLOR_BLACK;
159 }
160 #else
161 #define default_fg(sp) COLOR_WHITE
162 #define default_bg(sp) COLOR_BLACK
163 #endif
164 
165 #ifndef USE_TERM_DRIVER
166 /*
167  * SVr4 curses is known to interchange color codes (1,4) and (3,6), possibly
168  * to maintain compatibility with a pre-ANSI scheme.  The same scheme is
169  * also used in the FreeBSD syscons.
170  */
171 static int
172 toggled_colors(int c)
173 {
174     if (c < 16) {
175 	static const int table[] =
176 	{0, 4, 2, 6, 1, 5, 3, 7,
177 	 8, 12, 10, 14, 9, 13, 11, 15};
178 	c = table[c];
179     }
180     return c;
181 }
182 #endif
183 
184 static void
185 set_background_color(NCURSES_SP_DCLx int bg, NCURSES_SP_OUTC outc)
186 {
187 #ifdef USE_TERM_DRIVER
188     CallDriver_3(SP_PARM, td_color, FALSE, bg, outc);
189 #else
190     if (set_a_background) {
191 	TPUTS_TRACE("set_a_background");
192 	NCURSES_SP_NAME(tputs) (NCURSES_SP_ARGx
193 				TPARM_1(set_a_background, bg),
194 				1, outc);
195     } else {
196 	TPUTS_TRACE("set_background");
197 	NCURSES_SP_NAME(tputs) (NCURSES_SP_ARGx
198 				TPARM_1(set_background, toggled_colors(bg)),
199 				1, outc);
200     }
201 #endif
202 }
203 
204 static void
205 set_foreground_color(NCURSES_SP_DCLx int fg, NCURSES_SP_OUTC outc)
206 {
207 #ifdef USE_TERM_DRIVER
208     CallDriver_3(SP_PARM, td_color, TRUE, fg, outc);
209 #else
210     if (set_a_foreground) {
211 	TPUTS_TRACE("set_a_foreground");
212 	NCURSES_SP_NAME(tputs) (NCURSES_SP_ARGx
213 				TPARM_1(set_a_foreground, fg),
214 				1, outc);
215     } else {
216 	TPUTS_TRACE("set_foreground");
217 	NCURSES_SP_NAME(tputs) (NCURSES_SP_ARGx
218 				TPARM_1(set_foreground, toggled_colors(fg)),
219 				1, outc);
220     }
221 #endif
222 }
223 
224 static void
225 init_color_table(NCURSES_SP_DCL0)
226 {
227     const color_t *tp = DefaultPalette;
228     int n;
229 
230     assert(tp != 0);
231 
232     for (n = 0; n < COLORS; n++) {
233 	if (InPalette(n)) {
234 	    SP_PARM->_color_table[n] = tp[n];
235 	} else {
236 	    SP_PARM->_color_table[n] = tp[n % MAX_PALETTE];
237 	    if (UseHlsPalette) {
238 		SP_PARM->_color_table[n].green = 100;
239 	    } else {
240 		if (SP_PARM->_color_table[n].red)
241 		    SP_PARM->_color_table[n].red = 1000;
242 		if (SP_PARM->_color_table[n].green)
243 		    SP_PARM->_color_table[n].green = 1000;
244 		if (SP_PARM->_color_table[n].blue)
245 		    SP_PARM->_color_table[n].blue = 1000;
246 	    }
247 	}
248     }
249 }
250 
251 static bool
252 init_direct_colors(NCURSES_SP_DCL0)
253 {
254     static NCURSES_CONST char name[] = "RGB";
255 
256     int n;
257     const char *s;
258     int width;
259     rgb_bits_t *result = &(SP_PARM->_direct_color);
260 
261     result->value = 0;
262 
263     if (COLORS >= 8) {
264 	/* find the number of bits needed for the maximum color value */
265 	for (width = 0; (1 << width) - 1 < (COLORS - 1); ++width) {
266 	    ;
267 	}
268 
269 	if ((n = tigetflag(name)) > 0) {
270 	    n = (width + 2) / 3;
271 	    result->bits.red = UChar(n);
272 	    result->bits.green = UChar(n);
273 	    result->bits.blue = UChar(width - (2 * n));
274 	} else if ((n = tigetnum(name)) > 0) {
275 	    result->bits.red = UChar(n);
276 	    result->bits.green = UChar(n);
277 	    result->bits.blue = UChar(n);
278 	} else if ((s = tigetstr(name)) != 0 && VALID_STRING(s)) {
279 	    int red = n;
280 	    int green = n;
281 	    int blue = width - (2 * n);
282 
283 	    switch (sscanf(s, "%d/%d/%d", &red, &green, &blue)) {
284 	    default:
285 		blue = width - (2 * n);
286 		/* FALLTHRU */
287 	    case 1:
288 		green = n;
289 		/* FALLTHRU */
290 	    case 2:
291 		red = n;
292 		/* FALLTHRU */
293 	    case 3:
294 		/* okay */
295 		break;
296 	    }
297 	    result->bits.red = UChar(red);
298 	    result->bits.green = UChar(green);
299 	    result->bits.blue = UChar(blue);
300 	}
301     }
302     return (result->value != 0);
303 }
304 
305 /*
306  * Reset the color pair, e.g., to whatever color pair 0 is.
307  */
308 static bool
309 reset_color_pair(NCURSES_SP_DCL0)
310 {
311 #ifdef USE_TERM_DRIVER
312     return CallDriver(SP_PARM, td_rescol);
313 #else
314     bool result = FALSE;
315 
316     (void) SP_PARM;
317     if (orig_pair != 0) {
318 	(void) NCURSES_PUTP2("orig_pair", orig_pair);
319 	result = TRUE;
320     }
321     return result;
322 #endif
323 }
324 
325 /*
326  * Reset color pairs and definitions.  Actually we do both more to accommodate
327  * badly-written terminal descriptions than for the relatively rare case where
328  * someone has changed the color definitions.
329  */
330 NCURSES_EXPORT(bool)
331 NCURSES_SP_NAME(_nc_reset_colors) (NCURSES_SP_DCL0)
332 {
333     int result = FALSE;
334 
335     T((T_CALLED("_nc_reset_colors(%p)"), (void *) SP_PARM));
336     if (SP_PARM->_color_defs > 0)
337 	SP_PARM->_color_defs = -(SP_PARM->_color_defs);
338     if (reset_color_pair(NCURSES_SP_ARG))
339 	result = TRUE;
340 
341 #ifdef USE_TERM_DRIVER
342     result = CallDriver(SP_PARM, td_rescolors);
343 #else
344     if (orig_colors != 0) {
345 	NCURSES_PUTP2("orig_colors", orig_colors);
346 	result = TRUE;
347     }
348 #endif
349     returnBool(result);
350 }
351 
352 #if NCURSES_SP_FUNCS
353 NCURSES_EXPORT(bool)
354 _nc_reset_colors(void)
355 {
356     return NCURSES_SP_NAME(_nc_reset_colors) (CURRENT_SCREEN);
357 }
358 #endif
359 
360 NCURSES_EXPORT(int)
361 NCURSES_SP_NAME(start_color) (NCURSES_SP_DCL0)
362 {
363     int result = ERR;
364     int maxpairs = 0, maxcolors = 0;
365 
366     T((T_CALLED("start_color(%p)"), (void *) SP_PARM));
367 
368     if (SP_PARM == 0) {
369 	result = ERR;
370     } else if (SP_PARM->_coloron) {
371 	result = OK;
372     } else {
373 	maxpairs = MaxPairs;
374 	maxcolors = MaxColors;
375 	if (reset_color_pair(NCURSES_SP_ARG) != TRUE) {
376 	    set_foreground_color(NCURSES_SP_ARGx
377 				 default_fg(NCURSES_SP_ARG),
378 				 NCURSES_SP_NAME(_nc_outch));
379 	    set_background_color(NCURSES_SP_ARGx
380 				 default_bg(NCURSES_SP_ARG),
381 				 NCURSES_SP_NAME(_nc_outch));
382 	}
383 #if !NCURSES_EXT_COLORS
384 	/*
385 	 * Without ext-colors, we cannot represent more than 256 color pairs.
386 	 */
387 	if (maxpairs > 256)
388 	    maxpairs = 256;
389 #endif
390 
391 	if (maxpairs > 0 && maxcolors > 0) {
392 	    SP_PARM->_pair_limit = maxpairs;
393 
394 #if NCURSES_EXT_FUNCS
395 	    /*
396 	     * If using default colors, allocate extra space in table to
397 	     * allow for default-color as a component of a color-pair.
398 	     */
399 	    SP_PARM->_pair_limit += (1 + (2 * maxcolors));
400 #if !NCURSES_EXT_COLORS
401 	    SP_PARM->_pair_limit = limit_PAIRS(SP_PARM->_pair_limit);
402 #endif
403 #endif /* NCURSES_EXT_FUNCS */
404 	    SP_PARM->_pair_count = maxpairs;
405 	    SP_PARM->_color_count = maxcolors;
406 #if !USE_REENTRANT
407 	    COLOR_PAIRS = maxpairs;
408 	    COLORS = maxcolors;
409 #endif
410 
411 	    ReservePairs(SP_PARM, 16);
412 	    if (SP_PARM->_color_pairs != 0) {
413 		if (init_direct_colors(NCURSES_SP_ARG)) {
414 		    result = OK;
415 		} else {
416 		    SP_PARM->_color_table = TYPE_CALLOC(color_t, maxcolors);
417 		    if (SP_PARM->_color_table != 0) {
418 			MakeColorPair(SP_PARM->_color_pairs[0],
419 				      default_fg(NCURSES_SP_ARG),
420 				      default_bg(NCURSES_SP_ARG));
421 			init_color_table(NCURSES_SP_ARG);
422 
423 			result = OK;
424 		    }
425 		}
426 		if (result == OK) {
427 		    T(("started color: COLORS = %d, COLOR_PAIRS = %d",
428 		       COLORS, COLOR_PAIRS));
429 
430 		    SP_PARM->_coloron = 1;
431 		} else if (SP_PARM->_color_pairs != 0) {
432 		    FreeAndNull(SP_PARM->_color_pairs);
433 		}
434 	    }
435 	} else {
436 	    result = OK;
437 	}
438     }
439     returnCode(result);
440 }
441 
442 #if NCURSES_SP_FUNCS
443 NCURSES_EXPORT(int)
444 start_color(void)
445 {
446     return NCURSES_SP_NAME(start_color) (CURRENT_SCREEN);
447 }
448 #endif
449 
450 /* This function was originally written by Daniel Weaver <danw@znyx.com> */
451 static void
452 rgb2hls(int r, int g, int b, int *h, int *l, int *s)
453 /* convert RGB to HLS system */
454 {
455     int min, max, t;
456 
457     if ((min = g < r ? g : r) > b)
458 	min = b;
459     if ((max = g > r ? g : r) < b)
460 	max = b;
461 
462     /* calculate lightness */
463     *l = ((min + max) / 20);
464 
465     if (min == max) {		/* black, white and all shades of gray */
466 	*h = 0;
467 	*s = 0;
468 	return;
469     }
470 
471     /* calculate saturation */
472     if (*l < 50)
473 	*s = (((max - min) * 100) / (max + min));
474     else
475 	*s = (((max - min) * 100) / (2000 - max - min));
476 
477     /* calculate hue */
478     if (r == max)
479 	t = (120 + ((g - b) * 60) / (max - min));
480     else if (g == max)
481 	t = (240 + ((b - r) * 60) / (max - min));
482     else
483 	t = (360 + ((r - g) * 60) / (max - min));
484 
485     *h = (t % 360);
486 }
487 
488 /*
489  * Change all cells which use(d) a given color pair to force a repaint.
490  */
491 NCURSES_EXPORT(void)
492 _nc_change_pair(SCREEN *sp, int pair)
493 {
494     int y, x;
495 
496     if (CurScreen(sp)->_clear)
497 	return;
498 #if NO_LEAKS
499     if (_nc_globals.leak_checking)
500 	return;
501 #endif
502 
503     for (y = 0; y <= CurScreen(sp)->_maxy; y++) {
504 	struct ldat *ptr = &(CurScreen(sp)->_line[y]);
505 	bool changed = FALSE;
506 	for (x = 0; x <= CurScreen(sp)->_maxx; x++) {
507 	    if (GetPair(ptr->text[x]) == pair) {
508 		/* Set the old cell to zero to ensure it will be
509 		   updated on the next doupdate() */
510 		SetChar(ptr->text[x], 0, 0);
511 		CHANGED_CELL(ptr, x);
512 		changed = TRUE;
513 	    }
514 	}
515 	if (changed)
516 	    NCURSES_SP_NAME(_nc_make_oldhash) (NCURSES_SP_ARGx y);
517     }
518 }
519 
520 NCURSES_EXPORT(void)
521 _nc_reserve_pairs(SCREEN *sp, int want)
522 {
523     int have = sp->_pair_alloc;
524 
525     if (have == 0)
526 	have = 1;
527     while (have <= want)
528 	have *= 2;
529     if (have > sp->_pair_limit)
530 	have = sp->_pair_limit;
531 
532     if (sp->_color_pairs == 0) {
533 	sp->_color_pairs = TYPE_CALLOC(colorpair_t, have);
534     } else if (have > sp->_pair_alloc) {
535 #if NCURSES_EXT_COLORS
536 	colorpair_t *next;
537 
538 	if ((next = typeCalloc(colorpair_t, have)) == 0)
539 	    _nc_err_abort(MSG_NO_MEMORY);
540 	memcpy(next, sp->_color_pairs, (size_t) sp->_pair_alloc * sizeof(*next));
541 	_nc_copy_pairs(sp, next, sp->_color_pairs, sp->_pair_alloc);
542 	free(sp->_color_pairs);
543 	sp->_color_pairs = next;
544 #else
545 	TYPE_REALLOC(colorpair_t, have, sp->_color_pairs);
546 	if (sp->_color_pairs != 0) {
547 	    memset(sp->_color_pairs + sp->_pair_alloc, 0,
548 		   sizeof(colorpair_t) * (size_t) (have - sp->_pair_alloc));
549 	}
550 #endif
551     }
552     if (sp->_color_pairs != 0) {
553 	sp->_pair_alloc = have;
554     }
555 }
556 
557 /*
558  * Extension (1997/1/18) - Allow negative f/b values to set default color
559  * values.
560  */
561 NCURSES_EXPORT(int)
562 _nc_init_pair(SCREEN *sp, int pair, int f, int b)
563 {
564     static colorpair_t null_pair;
565     colorpair_t result = null_pair;
566     colorpair_t previous;
567     int maxcolors;
568 
569     T((T_CALLED("init_pair(%p,%d,%d,%d)"), (void *) sp, pair, f, b));
570 
571     if (!ValidPair(sp, pair))
572 	returnCode(ERR);
573 
574     maxcolors = MaxColors;
575 
576     ReservePairs(sp, pair);
577     previous = sp->_color_pairs[pair];
578 #if NCURSES_EXT_FUNCS
579     if (sp->_default_color || sp->_assumed_color) {
580 	bool isDefault = FALSE;
581 	bool wasDefault = FALSE;
582 	int default_pairs = sp->_default_pairs;
583 
584 	/*
585 	 * Map caller's color number, e.g., -1, 0, 1, .., 7, etc., into
586 	 * internal unsigned values which we will store in the _color_pairs[]
587 	 * table.
588 	 */
589 	if (isDefaultColor(f)) {
590 	    f = COLOR_DEFAULT;
591 	    isDefault = TRUE;
592 	} else if (!OkColorHi(f)) {
593 	    returnCode(ERR);
594 	}
595 
596 	if (isDefaultColor(b)) {
597 	    b = COLOR_DEFAULT;
598 	    isDefault = TRUE;
599 	} else if (!OkColorHi(b)) {
600 	    returnCode(ERR);
601 	}
602 
603 	/*
604 	 * Check if the table entry that we are going to init/update used
605 	 * default colors.
606 	 */
607 	if (isDefaultColor(FORE_OF(previous))
608 	    || isDefaultColor(BACK_OF(previous)))
609 	    wasDefault = TRUE;
610 
611 	/*
612 	 * Keep track of the number of entries in the color pair table which
613 	 * used a default color.
614 	 */
615 	if (isDefault && !wasDefault) {
616 	    ++default_pairs;
617 	} else if (wasDefault && !isDefault) {
618 	    --default_pairs;
619 	}
620 
621 	/*
622 	 * As an extension, ncurses allows the pair number to exceed the
623 	 * terminal's color_pairs value for pairs using a default color.
624 	 *
625 	 * Note that updating a pair which used a default color with one
626 	 * that does not will decrement the count - and possibly interfere
627 	 * with sequentially adding new pairs.
628 	 */
629 	if (pair > (sp->_pair_count + default_pairs)) {
630 	    returnCode(ERR);
631 	}
632 	sp->_default_pairs = default_pairs;
633     } else
634 #endif
635     {
636 	if ((f < 0) || !OkColorHi(f)
637 	    || (b < 0) || !OkColorHi(b)
638 	    || (pair < 1)) {
639 	    returnCode(ERR);
640 	}
641     }
642 
643     /*
644      * When a pair's content is changed, replace its colors (if pair was
645      * initialized before a screen update is performed replacing original
646      * pair colors with the new ones).
647      */
648     MakeColorPair(result, f, b);
649     if ((FORE_OF(previous) != 0
650 	 || BACK_OF(previous) != 0)
651 	&& !isSamePair(previous, result)) {
652 	_nc_change_pair(sp, pair);
653     }
654 
655     _nc_reset_color_pair(sp, pair, &result);
656     sp->_color_pairs[pair] = result;
657     _nc_set_color_pair(sp, pair, cpINIT);
658 
659     if (GET_SCREEN_PAIR(sp) == pair)
660 	SET_SCREEN_PAIR(sp, (int) (~0));	/* force attribute update */
661 
662 #ifdef USE_TERM_DRIVER
663     CallDriver_3(sp, td_initpair, pair, f, b);
664 #else
665     if (initialize_pair && InPalette(f) && InPalette(b)) {
666 	const color_t *tp = DefaultPalette;
667 
668 	TR(TRACE_ATTRS,
669 	   ("initializing pair: pair = %d, fg=(%d,%d,%d), bg=(%d,%d,%d)",
670 	    (int) pair,
671 	    (int) tp[f].red, (int) tp[f].green, (int) tp[f].blue,
672 	    (int) tp[b].red, (int) tp[b].green, (int) tp[b].blue));
673 
674 	NCURSES_PUTP2("initialize_pair",
675 		      TPARM_7(initialize_pair,
676 			      pair,
677 			      (int) tp[f].red,
678 			      (int) tp[f].green,
679 			      (int) tp[f].blue,
680 			      (int) tp[b].red,
681 			      (int) tp[b].green,
682 			      (int) tp[b].blue));
683     }
684 #endif
685 
686     returnCode(OK);
687 }
688 
689 NCURSES_EXPORT(int)
690 NCURSES_SP_NAME(init_pair) (NCURSES_SP_DCLx
691 			    NCURSES_PAIRS_T pair,
692 			    NCURSES_COLOR_T f,
693 			    NCURSES_COLOR_T b)
694 {
695     return _nc_init_pair(SP_PARM, pair, f, b);
696 }
697 
698 #if NCURSES_SP_FUNCS
699 NCURSES_EXPORT(int)
700 init_pair(NCURSES_COLOR_T pair, NCURSES_COLOR_T f, NCURSES_COLOR_T b)
701 {
702     return NCURSES_SP_NAME(init_pair) (CURRENT_SCREEN, pair, f, b);
703 }
704 #endif
705 
706 #define okRGB(n) ((n) >= 0 && (n) <= 1000)
707 
708 NCURSES_EXPORT(int)
709 _nc_init_color(SCREEN *sp, int color, int r, int g, int b)
710 {
711     int result = ERR;
712     int maxcolors;
713 
714     T((T_CALLED("init_color(%p,%d,%d,%d,%d)"),
715        (void *) sp,
716        color,
717        r, g, b));
718 
719     if (sp == 0 || sp->_direct_color.value)
720 	returnCode(result);
721 
722     maxcolors = MaxColors;
723 
724     if (InitColor
725 	&& sp->_coloron
726 	&& (color >= 0 && OkColorHi(color))
727 	&& (okRGB(r) && okRGB(g) && okRGB(b))) {
728 
729 	sp->_color_table[color].init = 1;
730 	sp->_color_table[color].r = r;
731 	sp->_color_table[color].g = g;
732 	sp->_color_table[color].b = b;
733 
734 	if (UseHlsPalette) {
735 	    rgb2hls(r, g, b,
736 		    &sp->_color_table[color].red,
737 		    &sp->_color_table[color].green,
738 		    &sp->_color_table[color].blue);
739 	} else {
740 	    sp->_color_table[color].red = r;
741 	    sp->_color_table[color].green = g;
742 	    sp->_color_table[color].blue = b;
743 	}
744 
745 #ifdef USE_TERM_DRIVER
746 	CallDriver_4(sp, td_initcolor, color, r, g, b);
747 #else
748 	NCURSES_PUTP2("initialize_color",
749 		      TPARM_4(initialize_color, color, r, g, b));
750 #endif
751 	sp->_color_defs = max(color + 1, sp->_color_defs);
752 
753 	result = OK;
754     }
755     returnCode(result);
756 }
757 
758 NCURSES_EXPORT(int)
759 NCURSES_SP_NAME(init_color) (NCURSES_SP_DCLx
760 			     NCURSES_COLOR_T color,
761 			     NCURSES_COLOR_T r,
762 			     NCURSES_COLOR_T g,
763 			     NCURSES_COLOR_T b)
764 {
765     return _nc_init_color(SP_PARM, color, r, g, b);
766 }
767 
768 #if NCURSES_SP_FUNCS
769 NCURSES_EXPORT(int)
770 init_color(NCURSES_COLOR_T color,
771 	   NCURSES_COLOR_T r,
772 	   NCURSES_COLOR_T g,
773 	   NCURSES_COLOR_T b)
774 {
775     return NCURSES_SP_NAME(init_color) (CURRENT_SCREEN, color, r, g, b);
776 }
777 #endif
778 
779 NCURSES_EXPORT(bool)
780 NCURSES_SP_NAME(can_change_color) (NCURSES_SP_DCL)
781 {
782     int result = FALSE;
783 
784     T((T_CALLED("can_change_color(%p)"), (void *) SP_PARM));
785 
786     if (HasTerminal(SP_PARM) && (CanChange != 0)) {
787 	result = TRUE;
788     }
789 
790     returnCode(result);
791 }
792 
793 #if NCURSES_SP_FUNCS
794 NCURSES_EXPORT(bool)
795 can_change_color(void)
796 {
797     return NCURSES_SP_NAME(can_change_color) (CURRENT_SCREEN);
798 }
799 #endif
800 
801 NCURSES_EXPORT(bool)
802 NCURSES_SP_NAME(has_colors) (NCURSES_SP_DCL0)
803 {
804     int code = FALSE;
805 
806     (void) SP_PARM;
807     T((T_CALLED("has_colors(%p)"), (void *) SP_PARM));
808     if (HasTerminal(SP_PARM)) {
809 #ifdef USE_TERM_DRIVER
810 	code = HasColor;
811 #else
812 	code = ((VALID_NUMERIC(max_colors) && VALID_NUMERIC(max_pairs)
813 		 && (((set_foreground != NULL)
814 		      && (set_background != NULL))
815 		     || ((set_a_foreground != NULL)
816 			 && (set_a_background != NULL))
817 		     || set_color_pair)) ? TRUE : FALSE);
818 #endif
819     }
820     returnCode(code);
821 }
822 
823 #if NCURSES_SP_FUNCS
824 NCURSES_EXPORT(bool)
825 has_colors(void)
826 {
827     return NCURSES_SP_NAME(has_colors) (CURRENT_SCREEN);
828 }
829 #endif
830 
831 static int
832 _nc_color_content(SCREEN *sp, int color, int *r, int *g, int *b)
833 {
834     int result = ERR;
835     int maxcolors;
836 
837     T((T_CALLED("color_content(%p,%d,%p,%p,%p)"),
838        (void *) sp,
839        color,
840        (void *) r,
841        (void *) g,
842        (void *) b));
843 
844     if (sp == 0)
845 	returnCode(result);
846 
847     maxcolors = MaxColors;
848 
849     if (color < 0 || !OkColorHi(color) || !sp->_coloron) {
850 	result = ERR;
851     } else {
852 	int c_r, c_g, c_b;
853 
854 	if (sp->_direct_color.value) {
855 	    rgb_bits_t *work = &(sp->_direct_color);
856 
857 #define max_direct_color(name)	((1 << work->bits.name) - 1)
858 #define value_direct_color(max) (1000 * ((color >> bitoff) & max)) / max
859 
860 	    int max_r = max_direct_color(red);
861 	    int max_g = max_direct_color(green);
862 	    int max_b = max_direct_color(blue);
863 
864 	    int bitoff = 0;
865 
866 	    c_b = value_direct_color(max_b);
867 	    bitoff += work->bits.blue;
868 
869 	    c_g = value_direct_color(max_g);
870 	    bitoff += work->bits.green;
871 
872 	    c_r = value_direct_color(max_r);
873 
874 	} else {
875 	    c_r = sp->_color_table[color].red;
876 	    c_g = sp->_color_table[color].green;
877 	    c_b = sp->_color_table[color].blue;
878 	}
879 
880 	if (r)
881 	    *r = c_r;
882 	if (g)
883 	    *g = c_g;
884 	if (b)
885 	    *b = c_b;
886 
887 	TR(TRACE_ATTRS, ("...color_content(%d,%d,%d,%d)",
888 			 color, c_r, c_g, c_b));
889 	result = OK;
890     }
891     returnCode(result);
892 }
893 
894 NCURSES_EXPORT(int)
895 NCURSES_SP_NAME(color_content) (NCURSES_SP_DCLx
896 				NCURSES_COLOR_T color,
897 				NCURSES_COLOR_T *r,
898 				NCURSES_COLOR_T *g,
899 				NCURSES_COLOR_T *b)
900 {
901     int my_r, my_g, my_b;
902     int rc = _nc_color_content(SP_PARM, color, &my_r, &my_g, &my_b);
903     if (rc == OK) {
904 	*r = limit_COLOR(my_r);
905 	*g = limit_COLOR(my_g);
906 	*b = limit_COLOR(my_b);
907     }
908     return rc;
909 }
910 
911 #if NCURSES_SP_FUNCS
912 NCURSES_EXPORT(int)
913 color_content(NCURSES_COLOR_T color,
914 	      NCURSES_COLOR_T *r,
915 	      NCURSES_COLOR_T *g,
916 	      NCURSES_COLOR_T *b)
917 {
918     return NCURSES_SP_NAME(color_content) (CURRENT_SCREEN, color, r, g, b);
919 }
920 #endif
921 
922 NCURSES_EXPORT(int)
923 _nc_pair_content(SCREEN *sp, int pair, int *f, int *b)
924 {
925     int result;
926 
927     T((T_CALLED("pair_content(%p,%d,%p,%p)"),
928        (void *) sp,
929        (int) pair,
930        (void *) f,
931        (void *) b));
932 
933     if (!ValidPair(sp, pair)) {
934 	result = ERR;
935     } else {
936 	int fg;
937 	int bg;
938 
939 	ReservePairs(sp, pair);
940 	fg = FORE_OF(sp->_color_pairs[pair]);
941 	bg = BACK_OF(sp->_color_pairs[pair]);
942 #if NCURSES_EXT_FUNCS
943 	if (isDefaultColor(fg))
944 	    fg = -1;
945 	if (isDefaultColor(bg))
946 	    bg = -1;
947 #endif
948 
949 	if (f)
950 	    *f = fg;
951 	if (b)
952 	    *b = bg;
953 
954 	TR(TRACE_ATTRS, ("...pair_content(%p,%d,%d,%d)",
955 			 (void *) sp,
956 			 (int) pair,
957 			 (int) fg, (int) bg));
958 	result = OK;
959     }
960     returnCode(result);
961 }
962 
963 NCURSES_EXPORT(int)
964 NCURSES_SP_NAME(pair_content) (NCURSES_SP_DCLx
965 			       NCURSES_PAIRS_T pair,
966 			       NCURSES_COLOR_T *f,
967 			       NCURSES_COLOR_T *b)
968 {
969     int my_f, my_b;
970     int rc = _nc_pair_content(SP_PARM, pair, &my_f, &my_b);
971     if (rc == OK) {
972 	*f = limit_COLOR(my_f);
973 	*b = limit_COLOR(my_b);
974     }
975     return rc;
976 }
977 
978 #if NCURSES_SP_FUNCS
979 NCURSES_EXPORT(int)
980 pair_content(NCURSES_COLOR_T pair, NCURSES_COLOR_T *f, NCURSES_COLOR_T *b)
981 {
982     return NCURSES_SP_NAME(pair_content) (CURRENT_SCREEN, pair, f, b);
983 }
984 #endif
985 
986 NCURSES_EXPORT(void)
987 NCURSES_SP_NAME(_nc_do_color) (NCURSES_SP_DCLx
988 			       int old_pair,
989 			       int pair,
990 			       int reverse,
991 			       NCURSES_SP_OUTC outc)
992 {
993 #ifdef USE_TERM_DRIVER
994     CallDriver_4(SP_PARM, td_docolor, old_pair, pair, reverse, outc);
995 #else
996     int fg = COLOR_DEFAULT;
997     int bg = COLOR_DEFAULT;
998     int old_fg = -1;
999     int old_bg = -1;
1000 
1001     if (!ValidPair(SP_PARM, pair)) {
1002 	return;
1003     } else if (pair != 0) {
1004 	if (set_color_pair) {
1005 	    TPUTS_TRACE("set_color_pair");
1006 	    NCURSES_SP_NAME(tputs) (NCURSES_SP_ARGx
1007 				    TPARM_1(set_color_pair, pair),
1008 				    1, outc);
1009 	    return;
1010 	} else if (SP_PARM != 0) {
1011 	    if (_nc_pair_content(SP_PARM, pair, &fg, &bg) == ERR)
1012 		return;
1013 	}
1014     }
1015 
1016     if (old_pair >= 0
1017 	&& SP_PARM != 0
1018 	&& _nc_pair_content(SP_PARM, old_pair, &old_fg, &old_bg) != ERR) {
1019 	if ((isDefaultColor(fg) && !isDefaultColor(old_fg))
1020 	    || (isDefaultColor(bg) && !isDefaultColor(old_bg))) {
1021 #if NCURSES_EXT_FUNCS
1022 	    /*
1023 	     * A minor optimization - but extension.  If "AX" is specified in
1024 	     * the terminal description, treat it as screen's indicator of ECMA
1025 	     * SGR 39 and SGR 49, and assume the two sequences are independent.
1026 	     */
1027 	    if (SP_PARM->_has_sgr_39_49
1028 		&& isDefaultColor(old_bg)
1029 		&& !isDefaultColor(old_fg)) {
1030 		NCURSES_SP_NAME(tputs) (NCURSES_SP_ARGx "\033[39m", 1, outc);
1031 	    } else if (SP_PARM->_has_sgr_39_49
1032 		       && isDefaultColor(old_fg)
1033 		       && !isDefaultColor(old_bg)) {
1034 		NCURSES_SP_NAME(tputs) (NCURSES_SP_ARGx "\033[49m", 1, outc);
1035 	    } else
1036 #endif
1037 		reset_color_pair(NCURSES_SP_ARG);
1038 	}
1039     } else {
1040 	reset_color_pair(NCURSES_SP_ARG);
1041 	if (old_pair < 0 && pair <= 0)
1042 	    return;
1043     }
1044 
1045 #if NCURSES_EXT_FUNCS
1046     if (isDefaultColor(fg))
1047 	fg = default_fg(NCURSES_SP_ARG);
1048     if (isDefaultColor(bg))
1049 	bg = default_bg(NCURSES_SP_ARG);
1050 #endif
1051 
1052     if (reverse) {
1053 	int xx = fg;
1054 	fg = bg;
1055 	bg = xx;
1056     }
1057 
1058     TR(TRACE_ATTRS, ("setting colors: pair = %d, fg = %d, bg = %d", pair,
1059 		     fg, bg));
1060 
1061     if (!isDefaultColor(fg)) {
1062 	set_foreground_color(NCURSES_SP_ARGx fg, outc);
1063     }
1064     if (!isDefaultColor(bg)) {
1065 	set_background_color(NCURSES_SP_ARGx bg, outc);
1066     }
1067 #endif
1068 }
1069 
1070 #if NCURSES_SP_FUNCS
1071 NCURSES_EXPORT(void)
1072 _nc_do_color(int old_pair, int pair, int reverse, NCURSES_OUTC outc)
1073 {
1074     SetSafeOutcWrapper(outc);
1075     NCURSES_SP_NAME(_nc_do_color) (CURRENT_SCREEN,
1076 				   old_pair,
1077 				   pair,
1078 				   reverse,
1079 				   _nc_outc_wrapper);
1080 }
1081 #endif
1082 
1083 #if NCURSES_EXT_COLORS
1084 NCURSES_EXPORT(int)
1085 NCURSES_SP_NAME(init_extended_pair) (NCURSES_SP_DCLx int pair, int f, int b)
1086 {
1087     return _nc_init_pair(SP_PARM, pair, f, b);
1088 }
1089 
1090 NCURSES_EXPORT(int)
1091 NCURSES_SP_NAME(init_extended_color) (NCURSES_SP_DCLx
1092 				      int color,
1093 				      int r, int g, int b)
1094 {
1095     return _nc_init_color(SP_PARM, color, r, g, b);
1096 }
1097 
1098 NCURSES_EXPORT(int)
1099 NCURSES_SP_NAME(extended_color_content) (NCURSES_SP_DCLx
1100 					 int color,
1101 					 int *r, int *g, int *b)
1102 {
1103     return _nc_color_content(SP_PARM, color, r, g, b);
1104 }
1105 
1106 NCURSES_EXPORT(int)
1107 NCURSES_SP_NAME(extended_pair_content) (NCURSES_SP_DCLx
1108 					int pair,
1109 					int *f, int *b)
1110 {
1111     return _nc_pair_content(SP_PARM, pair, f, b);
1112 }
1113 
1114 NCURSES_EXPORT(void)
1115 NCURSES_SP_NAME(reset_color_pairs) (NCURSES_SP_DCL0)
1116 {
1117     if (SP_PARM != 0) {
1118 	if (SP_PARM->_color_pairs) {
1119 	    _nc_free_ordered_pairs(SP_PARM);
1120 	    free(SP_PARM->_color_pairs);
1121 	    SP_PARM->_color_pairs = 0;
1122 	    SP_PARM->_pair_alloc = 0;
1123 	    ReservePairs(SP_PARM, 16);
1124 	    clearok(CurScreen(SP_PARM), TRUE);
1125 	    touchwin(StdScreen(SP_PARM));
1126 	}
1127     }
1128 }
1129 
1130 #if NCURSES_SP_FUNCS
1131 NCURSES_EXPORT(int)
1132 init_extended_pair(int pair, int f, int b)
1133 {
1134     return NCURSES_SP_NAME(init_extended_pair) (CURRENT_SCREEN, pair, f, b);
1135 }
1136 
1137 NCURSES_EXPORT(int)
1138 init_extended_color(int color, int r, int g, int b)
1139 {
1140     return NCURSES_SP_NAME(init_extended_color) (CURRENT_SCREEN,
1141 						 color,
1142 						 r, g, b);
1143 }
1144 
1145 NCURSES_EXPORT(int)
1146 extended_color_content(int color, int *r, int *g, int *b)
1147 {
1148     return NCURSES_SP_NAME(extended_color_content) (CURRENT_SCREEN,
1149 						    color,
1150 						    r, g, b);
1151 }
1152 
1153 NCURSES_EXPORT(int)
1154 extended_pair_content(int pair, int *f, int *b)
1155 {
1156     return NCURSES_SP_NAME(extended_pair_content) (CURRENT_SCREEN, pair, f, b);
1157 }
1158 
1159 NCURSES_EXPORT(void)
1160 reset_color_pairs(void)
1161 {
1162     NCURSES_SP_NAME(reset_color_pairs) (CURRENT_SCREEN);
1163 }
1164 #endif /* NCURSES_SP_FUNCS */
1165 #endif /* NCURSES_EXT_COLORS */
1166