1 /****************************************************************************
2  * Copyright (c) 1998-2004,2005 Free Software Foundation, Inc.              *
3  *                                                                          *
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5  * copy of this software and associated documentation files (the            *
6  * "Software"), to deal in the Software without restriction, including      *
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9  * copies of the Software, and to permit persons to whom the Software is    *
10  * furnished to do so, subject to the following conditions:                 *
11  *                                                                          *
12  * The above copyright notice and this permission notice shall be included  *
13  * in all copies or substantial portions of the Software.                   *
14  *                                                                          *
15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS  *
16  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF               *
17  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.   *
18  * IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,   *
19  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR    *
20  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR    *
21  * THE USE OR OTHER DEALINGS IN THE SOFTWARE.                               *
22  *                                                                          *
23  * Except as contained in this notice, the name(s) of the above copyright   *
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26  * authorization.                                                           *
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28 
29 /****************************************************************************
30  *  Author: Zeyd M. Ben-Halim <zmbenhal@netcom.com> 1992,1995               *
31  *     and: Eric S. Raymond <esr@snark.thyrsus.com>                         *
32  *     and: Thomas E. Dickey                        1996-on                 *
33  ****************************************************************************/
34 
35 /* lib_color.c
36  *
37  * Handles color emulation of SYS V curses
38  */
39 
40 #include <curses.priv.h>
41 
42 #include <term.h>
43 #include <tic.h>
44 
45 MODULE_ID("$Id: lib_color.c,v 1.75 2005/06/18 20:19:08 tom Exp $")
46 
47 /*
48  * These should be screen structure members.  They need to be globals for
49  * historical reasons.  So we assign them in start_color() and also in
50  * set_term()'s screen-switching logic.
51  */
52 NCURSES_EXPORT_VAR(int) COLOR_PAIRS = 0;
53 NCURSES_EXPORT_VAR(int) COLORS = 0;
54 
55 #define DATA(r,g,b) {r,g,b, 0,0,0, 0}
56 
57 #define TYPE_CALLOC(type,elts) typeCalloc(type, (unsigned)(elts))
58 
59 /*
60  * Given a RGB range of 0..1000, we'll normally set the individual values
61  * to about 2/3 of the maximum, leaving full-range for bold/bright colors.
62  */
63 #define RGB_ON  680
64 #define RGB_OFF 0
65 /* *INDENT-OFF* */
66 static const color_t cga_palette[] =
67 {
68     /*  R               G               B */
69     DATA(RGB_OFF,	RGB_OFF,	RGB_OFF),	/* COLOR_BLACK */
70     DATA(RGB_ON,	RGB_OFF,	RGB_OFF),	/* COLOR_RED */
71     DATA(RGB_OFF,	RGB_ON,		RGB_OFF),	/* COLOR_GREEN */
72     DATA(RGB_ON,	RGB_ON,		RGB_OFF),	/* COLOR_YELLOW */
73     DATA(RGB_OFF,	RGB_OFF,	RGB_ON),	/* COLOR_BLUE */
74     DATA(RGB_ON,	RGB_OFF,	RGB_ON),	/* COLOR_MAGENTA */
75     DATA(RGB_OFF,	RGB_ON,		RGB_ON),	/* COLOR_CYAN */
76     DATA(RGB_ON,	RGB_ON,		RGB_ON),	/* COLOR_WHITE */
77 };
78 
79 static const color_t hls_palette[] =
80 {
81     /*  	H       L       S */
82     DATA(	0,	0,	0),		/* COLOR_BLACK */
83     DATA(	120,	50,	100),		/* COLOR_RED */
84     DATA(	240,	50,	100),		/* COLOR_GREEN */
85     DATA(	180,	50,	100),		/* COLOR_YELLOW */
86     DATA(	330,	50,	100),		/* COLOR_BLUE */
87     DATA(	60,	50,	100),		/* COLOR_MAGENTA */
88     DATA(	300,	50,	100),		/* COLOR_CYAN */
89     DATA(	0,	50,	100),		/* COLOR_WHITE */
90 };
91 /* *INDENT-ON* */
92 
93 #if NCURSES_EXT_FUNCS
94 /*
95  * These are called from _nc_do_color(), which in turn is called from
96  * vidattr - so we have to assume that SP may be null.
97  */
98 static int
default_fg(void)99 default_fg(void)
100 {
101     return (SP != 0) ? SP->_default_fg : COLOR_WHITE;
102 }
103 
104 static int
default_bg(void)105 default_bg(void)
106 {
107     return SP != 0 ? SP->_default_bg : COLOR_BLACK;
108 }
109 #else
110 #define default_fg() COLOR_WHITE
111 #define default_bg() COLOR_BLACK
112 #endif
113 
114 /*
115  * SVr4 curses is known to interchange color codes (1,4) and (3,6), possibly
116  * to maintain compatibility with a pre-ANSI scheme.  The same scheme is
117  * also used in the FreeBSD syscons.
118  */
119 static int
toggled_colors(int c)120 toggled_colors(int c)
121 {
122     if (c < 16) {
123 	static const int table[] =
124 	{0, 4, 2, 6, 1, 5, 3, 7,
125 	 8, 12, 10, 14, 9, 13, 11, 15};
126 	c = table[c];
127     }
128     return c;
129 }
130 
131 static void
set_background_color(int bg,int (* outc)(int))132 set_background_color(int bg, int (*outc) (int))
133 {
134     if (set_a_background) {
135 	TPUTS_TRACE("set_a_background");
136 	tputs(tparm(set_a_background, bg), 1, outc);
137     } else {
138 	TPUTS_TRACE("set_background");
139 	tputs(tparm(set_background, toggled_colors(bg)), 1, outc);
140     }
141 }
142 
143 static void
set_foreground_color(int fg,int (* outc)(int))144 set_foreground_color(int fg, int (*outc) (int))
145 {
146     if (set_a_foreground) {
147 	TPUTS_TRACE("set_a_foreground");
148 	tputs(tparm(set_a_foreground, fg), 1, outc);
149     } else {
150 	TPUTS_TRACE("set_foreground");
151 	tputs(tparm(set_foreground, toggled_colors(fg)), 1, outc);
152     }
153 }
154 
155 static void
init_color_table(void)156 init_color_table(void)
157 {
158     const color_t *tp;
159     int n;
160 
161     tp = (hue_lightness_saturation) ? hls_palette : cga_palette;
162     for (n = 0; n < COLORS; n++) {
163 	if (n < 8) {
164 	    SP->_color_table[n] = tp[n];
165 	} else {
166 	    SP->_color_table[n] = tp[n % 8];
167 	    if (hue_lightness_saturation) {
168 		SP->_color_table[n].green = 100;
169 	    } else {
170 		if (SP->_color_table[n].red)
171 		    SP->_color_table[n].red = 1000;
172 		if (SP->_color_table[n].green)
173 		    SP->_color_table[n].green = 1000;
174 		if (SP->_color_table[n].blue)
175 		    SP->_color_table[n].blue = 1000;
176 	    }
177 	}
178     }
179 }
180 
181 /*
182  * Reset the color pair, e.g., to whatever color pair 0 is.
183  */
184 static bool
reset_color_pair(void)185 reset_color_pair(void)
186 {
187     bool result = FALSE;
188 
189     if (orig_pair != 0) {
190 	TPUTS_TRACE("orig_pair");
191 	putp(orig_pair);
192 	result = TRUE;
193     }
194     return result;
195 }
196 
197 /*
198  * Reset color pairs and definitions.  Actually we do both more to accommodate
199  * badly-written terminal descriptions than for the relatively rare case where
200  * someone has changed the color definitions.
201  */
202 bool
_nc_reset_colors(void)203 _nc_reset_colors(void)
204 {
205     int result = FALSE;
206 
207     T((T_CALLED("_nc_reset_colors()")));
208     if (SP->_color_defs > 0)
209 	SP->_color_defs = -(SP->_color_defs);
210 
211     if (reset_color_pair())
212 	result = TRUE;
213     if (orig_colors != 0) {
214 	TPUTS_TRACE("orig_colors");
215 	putp(orig_colors);
216 	result = TRUE;
217     }
218     returnBool(result);
219 }
220 
221 NCURSES_EXPORT(int)
start_color(void)222 start_color(void)
223 {
224     int result = ERR;
225 
226     T((T_CALLED("start_color()")));
227 
228     if (SP == 0) {
229 	result = ERR;
230     } else if (SP->_coloron) {
231 	result = OK;
232     } else {
233 
234 	if (reset_color_pair() != TRUE) {
235 	    set_foreground_color(default_fg(), _nc_outch);
236 	    set_background_color(default_bg(), _nc_outch);
237 	}
238 
239 	if (max_pairs > 0 && max_colors > 0) {
240 	    COLOR_PAIRS = SP->_pair_count = max_pairs;
241 	    COLORS = SP->_color_count = max_colors;
242 
243 	    if ((SP->_color_pairs = TYPE_CALLOC(colorpair_t,
244 						max_pairs)) != 0) {
245 		if ((SP->_color_table = TYPE_CALLOC(color_t,
246 						    max_colors)) != 0) {
247 		    SP->_color_pairs[0] = PAIR_OF(default_fg(), default_bg());
248 		    init_color_table();
249 
250 		    T(("started color: COLORS = %d, COLOR_PAIRS = %d",
251 		       COLORS, COLOR_PAIRS));
252 
253 		    SP->_coloron = 1;
254 		    result = OK;
255 		} else if (SP->_color_pairs != 0) {
256 		    FreeAndNull(SP->_color_pairs);
257 		}
258 	    }
259 	} else {
260 	    result = OK;
261 	}
262     }
263     returnCode(result);
264 }
265 
266 /* This function was originally written by Daniel Weaver <danw@znyx.com> */
267 static void
rgb2hls(short r,short g,short b,short * h,short * l,short * s)268 rgb2hls(short r, short g, short b, short *h, short *l, short *s)
269 /* convert RGB to HLS system */
270 {
271     short min, max, t;
272 
273     if ((min = g < r ? g : r) > b)
274 	min = b;
275     if ((max = g > r ? g : r) < b)
276 	max = b;
277 
278     /* calculate lightness */
279     *l = (min + max) / 20;
280 
281     if (min == max) {		/* black, white and all shades of gray */
282 	*h = 0;
283 	*s = 0;
284 	return;
285     }
286 
287     /* calculate saturation */
288     if (*l < 50)
289 	*s = ((max - min) * 100) / (max + min);
290     else
291 	*s = ((max - min) * 100) / (2000 - max - min);
292 
293     /* calculate hue */
294     if (r == max)
295 	t = 120 + ((g - b) * 60) / (max - min);
296     else if (g == max)
297 	t = 240 + ((b - r) * 60) / (max - min);
298     else
299 	t = 360 + ((r - g) * 60) / (max - min);
300 
301     *h = t % 360;
302 }
303 
304 /*
305  * Extension (1997/1/18) - Allow negative f/b values to set default color
306  * values.
307  */
308 NCURSES_EXPORT(int)
init_pair(short pair,short f,short b)309 init_pair(short pair, short f, short b)
310 {
311     colorpair_t result;
312 
313     T((T_CALLED("init_pair(%d,%d,%d)"), pair, f, b));
314 
315     if ((pair < 0) || (pair >= COLOR_PAIRS) || SP == 0 || !SP->_coloron)
316 	returnCode(ERR);
317 #if NCURSES_EXT_FUNCS
318     if (SP->_default_color) {
319 	if (f < 0)
320 	    f = COLOR_DEFAULT;
321 	if (b < 0)
322 	    b = COLOR_DEFAULT;
323 	if (f >= COLORS && !isDefaultColor(f))
324 	    returnCode(ERR);
325 	if (b >= COLORS && !isDefaultColor(b))
326 	    returnCode(ERR);
327     } else
328 #endif
329     {
330 	if ((f < 0) || (f >= COLORS)
331 	    || (b < 0) || (b >= COLORS)
332 	    || (pair < 1))
333 	    returnCode(ERR);
334     }
335 
336     /*
337      * When a pair's content is changed, replace its colors (if pair was
338      * initialized before a screen update is performed replacing original
339      * pair colors with the new ones).
340      */
341     result = PAIR_OF(f, b);
342     if (SP->_color_pairs[pair] != 0
343 	&& SP->_color_pairs[pair] != result) {
344 	int y, x;
345 
346 	for (y = 0; y <= curscr->_maxy; y++) {
347 	    struct ldat *ptr = &(curscr->_line[y]);
348 	    bool changed = FALSE;
349 	    for (x = 0; x <= curscr->_maxx; x++) {
350 		if (GetPair(ptr->text[x]) == pair) {
351 		    /* Set the old cell to zero to ensure it will be
352 		       updated on the next doupdate() */
353 		    SetChar(ptr->text[x], 0, 0);
354 		    CHANGED_CELL(ptr, x);
355 		    changed = TRUE;
356 		}
357 	    }
358 	    if (changed)
359 		_nc_make_oldhash(y);
360 	}
361     }
362     SP->_color_pairs[pair] = result;
363     if (GET_SCREEN_PAIR(SP) == pair)
364 	SET_SCREEN_PAIR(SP, ~0);	/* force attribute update */
365 
366     if (initialize_pair) {
367 	const color_t *tp = hue_lightness_saturation ? hls_palette : cga_palette;
368 
369 	T(("initializing pair: pair = %d, fg=(%d,%d,%d), bg=(%d,%d,%d)",
370 	   pair,
371 	   tp[f].red, tp[f].green, tp[f].blue,
372 	   tp[b].red, tp[b].green, tp[b].blue));
373 
374 	if (initialize_pair) {
375 	    TPUTS_TRACE("initialize_pair");
376 	    putp(tparm(initialize_pair,
377 		       pair,
378 		       tp[f].red, tp[f].green, tp[f].blue,
379 		       tp[b].red, tp[b].green, tp[b].blue));
380 	}
381     }
382 
383     returnCode(OK);
384 }
385 
386 #define okRGB(n) ((n) >= 0 && (n) <= 1000)
387 
388 NCURSES_EXPORT(int)
init_color(short color,short r,short g,short b)389 init_color(short color, short r, short g, short b)
390 {
391     int result = ERR;
392 
393     T((T_CALLED("init_color(%d,%d,%d,%d)"), color, r, g, b));
394 
395     if (initialize_color != NULL
396 	&& SP != 0
397 	&& SP->_coloron
398 	&& (color >= 0 && color < COLORS)
399 	&& (okRGB(r) && okRGB(g) && okRGB(b))) {
400 
401 	SP->_color_table[color].init = 1;
402 	SP->_color_table[color].r = r;
403 	SP->_color_table[color].g = g;
404 	SP->_color_table[color].b = b;
405 
406 	if (hue_lightness_saturation) {
407 	    rgb2hls(r, g, b,
408 		    &SP->_color_table[color].red,
409 		    &SP->_color_table[color].green,
410 		    &SP->_color_table[color].blue);
411 	} else {
412 	    SP->_color_table[color].red = r;
413 	    SP->_color_table[color].green = g;
414 	    SP->_color_table[color].blue = b;
415 	}
416 
417 	TPUTS_TRACE("initialize_color");
418 	putp(tparm(initialize_color, color, r, g, b));
419 	SP->_color_defs = max(color + 1, SP->_color_defs);
420 	result = OK;
421     }
422     returnCode(result);
423 }
424 
425 NCURSES_EXPORT(bool)
can_change_color(void)426 can_change_color(void)
427 {
428     T((T_CALLED("can_change_color()")));
429     returnCode((can_change != 0) ? TRUE : FALSE);
430 }
431 
432 NCURSES_EXPORT(bool)
has_colors(void)433 has_colors(void)
434 {
435     T((T_CALLED("has_colors()")));
436     returnCode((VALID_NUMERIC(max_colors) && VALID_NUMERIC(max_pairs)
437 		&& (((set_foreground != NULL)
438 		     && (set_background != NULL))
439 		    || ((set_a_foreground != NULL)
440 			&& (set_a_background != NULL))
441 		    || set_color_pair)) ? TRUE : FALSE);
442 }
443 
444 NCURSES_EXPORT(int)
color_content(short color,short * r,short * g,short * b)445 color_content(short color, short *r, short *g, short *b)
446 {
447     int result;
448 
449     T((T_CALLED("color_content(%d,%p,%p,%p)"), color, r, g, b));
450     if (color < 0 || color >= COLORS || SP == 0 || !SP->_coloron) {
451 	result = ERR;
452     } else {
453 	NCURSES_COLOR_T c_r = SP->_color_table[color].red;
454 	NCURSES_COLOR_T c_g = SP->_color_table[color].green;
455 	NCURSES_COLOR_T c_b = SP->_color_table[color].blue;
456 
457 	if (r)
458 	    *r = c_r;
459 	if (g)
460 	    *g = c_g;
461 	if (b)
462 	    *b = c_b;
463 
464 	T(("...color_content(%d,%d,%d,%d)", color, c_r, c_g, c_b));
465 	result = OK;
466     }
467     returnCode(result);
468 }
469 
470 NCURSES_EXPORT(int)
pair_content(short pair,short * f,short * b)471 pair_content(short pair, short *f, short *b)
472 {
473     int result;
474 
475     T((T_CALLED("pair_content(%d,%p,%p)"), pair, f, b));
476 
477     if ((pair < 0) || (pair >= COLOR_PAIRS) || SP == 0 || !SP->_coloron) {
478 	result = ERR;
479     } else {
480 	NCURSES_COLOR_T fg = ((SP->_color_pairs[pair] >> C_SHIFT) & C_MASK);
481 	NCURSES_COLOR_T bg = (SP->_color_pairs[pair] & C_MASK);
482 
483 #if NCURSES_EXT_FUNCS
484 	if (fg == COLOR_DEFAULT)
485 	    fg = -1;
486 	if (bg == COLOR_DEFAULT)
487 	    bg = -1;
488 #endif
489 
490 	if (f)
491 	    *f = fg;
492 	if (b)
493 	    *b = bg;
494 
495 	T(("...pair_content(%d,%d,%d)", pair, fg, bg));
496 	result = OK;
497     }
498     returnCode(result);
499 }
500 
501 NCURSES_EXPORT(void)
_nc_do_color(int old_pair,int pair,bool reverse,int (* outc)(int))502 _nc_do_color(int old_pair, int pair, bool reverse, int (*outc) (int))
503 {
504     NCURSES_COLOR_T fg = COLOR_DEFAULT;
505     NCURSES_COLOR_T bg = COLOR_DEFAULT;
506     NCURSES_COLOR_T old_fg, old_bg;
507 
508     if (pair < 0 || pair >= COLOR_PAIRS) {
509 	return;
510     } else if (pair != 0) {
511 	if (set_color_pair) {
512 	    TPUTS_TRACE("set_color_pair");
513 	    tputs(tparm(set_color_pair, pair), 1, outc);
514 	    return;
515 	} else if (SP != 0) {
516 	    pair_content(pair, &fg, &bg);
517 	}
518     }
519 
520     if (old_pair >= 0
521 	&& SP != 0
522 	&& pair_content(old_pair, &old_fg, &old_bg) != ERR) {
523 	if ((isDefaultColor(fg) && !isDefaultColor(old_fg))
524 	    || (isDefaultColor(bg) && !isDefaultColor(old_bg))) {
525 #if NCURSES_EXT_FUNCS
526 	    /*
527 	     * A minor optimization - but extension.  If "AX" is specified in
528 	     * the terminal description, treat it as screen's indicator of ECMA
529 	     * SGR 39 and SGR 49, and assume the two sequences are independent.
530 	     */
531 	    if (SP->_has_sgr_39_49
532 		&& isDefaultColor(old_bg)
533 		&& !isDefaultColor(old_fg)) {
534 		tputs("\033[39m", 1, outc);
535 	    } else if (SP->_has_sgr_39_49
536 		       && isDefaultColor(old_fg)
537 		       && !isDefaultColor(old_bg)) {
538 		tputs("\033[49m", 1, outc);
539 	    } else
540 #endif
541 		reset_color_pair();
542 	}
543     } else {
544 	reset_color_pair();
545 	if (old_pair < 0)
546 	    return;
547     }
548 
549 #if NCURSES_EXT_FUNCS
550     if (isDefaultColor(fg))
551 	fg = default_fg();
552     if (isDefaultColor(bg))
553 	bg = default_bg();
554 #endif
555 
556     if (reverse) {
557 	NCURSES_COLOR_T xx = fg;
558 	fg = bg;
559 	bg = xx;
560     }
561 
562     TR(TRACE_ATTRS, ("setting colors: pair = %d, fg = %d, bg = %d", pair,
563 		     fg, bg));
564 
565     if (!isDefaultColor(fg)) {
566 	set_foreground_color(fg, outc);
567     }
568     if (!isDefaultColor(bg)) {
569 	set_background_color(bg, outc);
570     }
571 }
572