libsl

shared code master of various suckless projects
git clone git://git.suckless.org/libsl
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drw.c (11609B)


      1 /* See LICENSE file for copyright and license details. */
      2 #include <stdio.h>
      3 #include <stdlib.h>
      4 #include <string.h>
      5 #include <X11/Xlib.h>
      6 #include <X11/Xft/Xft.h>
      7 
      8 #include "drw.h"
      9 #include "util.h"
     10 
     11 #define UTF_INVALID 0xFFFD
     12 #define UTF_SIZ     4
     13 
     14 static const unsigned char utfbyte[UTF_SIZ + 1] = {0x80,    0, 0xC0, 0xE0, 0xF0};
     15 static const unsigned char utfmask[UTF_SIZ + 1] = {0xC0, 0x80, 0xE0, 0xF0, 0xF8};
     16 static const long utfmin[UTF_SIZ + 1] = {       0,    0,  0x80,  0x800,  0x10000};
     17 static const long utfmax[UTF_SIZ + 1] = {0x10FFFF, 0x7F, 0x7FF, 0xFFFF, 0x10FFFF};
     18 
     19 static long
     20 utf8decodebyte(const char c, size_t *i)
     21 {
     22 	for (*i = 0; *i < (UTF_SIZ + 1); ++(*i))
     23 		if (((unsigned char)c & utfmask[*i]) == utfbyte[*i])
     24 			return (unsigned char)c & ~utfmask[*i];
     25 	return 0;
     26 }
     27 
     28 static size_t
     29 utf8validate(long *u, size_t i)
     30 {
     31 	if (!BETWEEN(*u, utfmin[i], utfmax[i]) || BETWEEN(*u, 0xD800, 0xDFFF))
     32 		*u = UTF_INVALID;
     33 	for (i = 1; *u > utfmax[i]; ++i)
     34 		;
     35 	return i;
     36 }
     37 
     38 static size_t
     39 utf8decode(const char *c, long *u, size_t clen)
     40 {
     41 	size_t i, j, len, type;
     42 	long udecoded;
     43 
     44 	*u = UTF_INVALID;
     45 	if (!clen)
     46 		return 0;
     47 	udecoded = utf8decodebyte(c[0], &len);
     48 	if (!BETWEEN(len, 1, UTF_SIZ))
     49 		return 1;
     50 	for (i = 1, j = 1; i < clen && j < len; ++i, ++j) {
     51 		udecoded = (udecoded << 6) | utf8decodebyte(c[i], &type);
     52 		if (type)
     53 			return j;
     54 	}
     55 	if (j < len)
     56 		return 0;
     57 	*u = udecoded;
     58 	utf8validate(u, len);
     59 
     60 	return len;
     61 }
     62 
     63 Drw *
     64 drw_create(Display *dpy, int screen, Window root, unsigned int w, unsigned int h)
     65 {
     66 	Drw *drw = ecalloc(1, sizeof(Drw));
     67 
     68 	drw->dpy = dpy;
     69 	drw->screen = screen;
     70 	drw->root = root;
     71 	drw->w = w;
     72 	drw->h = h;
     73 	drw->drawable = XCreatePixmap(dpy, root, w, h, DefaultDepth(dpy, screen));
     74 	drw->gc = XCreateGC(dpy, root, 0, NULL);
     75 	XSetLineAttributes(dpy, drw->gc, 1, LineSolid, CapButt, JoinMiter);
     76 
     77 	return drw;
     78 }
     79 
     80 void
     81 drw_resize(Drw *drw, unsigned int w, unsigned int h)
     82 {
     83 	if (!drw)
     84 		return;
     85 
     86 	drw->w = w;
     87 	drw->h = h;
     88 	if (drw->drawable)
     89 		XFreePixmap(drw->dpy, drw->drawable);
     90 	drw->drawable = XCreatePixmap(drw->dpy, drw->root, w, h, DefaultDepth(drw->dpy, drw->screen));
     91 }
     92 
     93 void
     94 drw_free(Drw *drw)
     95 {
     96 	XFreePixmap(drw->dpy, drw->drawable);
     97 	XFreeGC(drw->dpy, drw->gc);
     98 	drw_fontset_free(drw->fonts);
     99 	free(drw);
    100 }
    101 
    102 /* This function is an implementation detail. Library users should use
    103  * drw_fontset_create instead.
    104  */
    105 static Fnt *
    106 xfont_create(Drw *drw, const char *fontname, FcPattern *fontpattern)
    107 {
    108 	Fnt *font;
    109 	XftFont *xfont = NULL;
    110 	FcPattern *pattern = NULL;
    111 
    112 	if (fontname) {
    113 		/* Using the pattern found at font->xfont->pattern does not yield the
    114 		 * same substitution results as using the pattern returned by
    115 		 * FcNameParse; using the latter results in the desired fallback
    116 		 * behaviour whereas the former just results in missing-character
    117 		 * rectangles being drawn, at least with some fonts. */
    118 		if (!(xfont = XftFontOpenName(drw->dpy, drw->screen, fontname))) {
    119 			fprintf(stderr, "error, cannot load font from name: '%s'\n", fontname);
    120 			return NULL;
    121 		}
    122 		if (!(pattern = FcNameParse((FcChar8 *) fontname))) {
    123 			fprintf(stderr, "error, cannot parse font name to pattern: '%s'\n", fontname);
    124 			XftFontClose(drw->dpy, xfont);
    125 			return NULL;
    126 		}
    127 	} else if (fontpattern) {
    128 		if (!(xfont = XftFontOpenPattern(drw->dpy, fontpattern))) {
    129 			fprintf(stderr, "error, cannot load font from pattern.\n");
    130 			return NULL;
    131 		}
    132 	} else {
    133 		die("no font specified.");
    134 	}
    135 
    136 	/* Do not allow using color fonts. This is a workaround for a BadLength
    137 	 * error from Xft with color glyphs. Modelled on the Xterm workaround. See
    138 	 * https://bugzilla.redhat.com/show_bug.cgi?id=1498269
    139 	 * https://lists.suckless.org/dev/1701/30932.html
    140 	 * https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=916349
    141 	 * and lots more all over the internet.
    142 	 */
    143 	FcBool iscol;
    144 	if(FcPatternGetBool(xfont->pattern, FC_COLOR, 0, &iscol) == FcResultMatch && iscol) {
    145 		XftFontClose(drw->dpy, xfont);
    146 		return NULL;
    147 	}
    148 
    149 	font = ecalloc(1, sizeof(Fnt));
    150 	font->xfont = xfont;
    151 	font->pattern = pattern;
    152 	font->h = xfont->ascent + xfont->descent;
    153 	font->dpy = drw->dpy;
    154 
    155 	return font;
    156 }
    157 
    158 static void
    159 xfont_free(Fnt *font)
    160 {
    161 	if (!font)
    162 		return;
    163 	if (font->pattern)
    164 		FcPatternDestroy(font->pattern);
    165 	XftFontClose(font->dpy, font->xfont);
    166 	free(font);
    167 }
    168 
    169 Fnt*
    170 drw_fontset_create(Drw* drw, const char *fonts[], size_t fontcount)
    171 {
    172 	Fnt *cur, *ret = NULL;
    173 	size_t i;
    174 
    175 	if (!drw || !fonts)
    176 		return NULL;
    177 
    178 	for (i = 1; i <= fontcount; i++) {
    179 		if ((cur = xfont_create(drw, fonts[fontcount - i], NULL))) {
    180 			cur->next = ret;
    181 			ret = cur;
    182 		}
    183 	}
    184 	return (drw->fonts = ret);
    185 }
    186 
    187 void
    188 drw_fontset_free(Fnt *font)
    189 {
    190 	if (font) {
    191 		drw_fontset_free(font->next);
    192 		xfont_free(font);
    193 	}
    194 }
    195 
    196 void
    197 drw_clr_create(Drw *drw, Clr *dest, const char *clrname)
    198 {
    199 	if (!drw || !dest || !clrname)
    200 		return;
    201 
    202 	if (!XftColorAllocName(drw->dpy, DefaultVisual(drw->dpy, drw->screen),
    203 	                       DefaultColormap(drw->dpy, drw->screen),
    204 	                       clrname, dest))
    205 		die("error, cannot allocate color '%s'", clrname);
    206 }
    207 
    208 /* Wrapper to create color schemes. The caller has to call free(3) on the
    209  * returned color scheme when done using it. */
    210 Clr *
    211 drw_scm_create(Drw *drw, const char *clrnames[], size_t clrcount)
    212 {
    213 	size_t i;
    214 	Clr *ret;
    215 
    216 	/* need at least two colors for a scheme */
    217 	if (!drw || !clrnames || clrcount < 2 || !(ret = ecalloc(clrcount, sizeof(XftColor))))
    218 		return NULL;
    219 
    220 	for (i = 0; i < clrcount; i++)
    221 		drw_clr_create(drw, &ret[i], clrnames[i]);
    222 	return ret;
    223 }
    224 
    225 void
    226 drw_setfontset(Drw *drw, Fnt *set)
    227 {
    228 	if (drw)
    229 		drw->fonts = set;
    230 }
    231 
    232 void
    233 drw_setscheme(Drw *drw, Clr *scm)
    234 {
    235 	if (drw)
    236 		drw->scheme = scm;
    237 }
    238 
    239 void
    240 drw_rect(Drw *drw, int x, int y, unsigned int w, unsigned int h, int filled, int invert)
    241 {
    242 	if (!drw || !drw->scheme)
    243 		return;
    244 	XSetForeground(drw->dpy, drw->gc, invert ? drw->scheme[ColBg].pixel : drw->scheme[ColFg].pixel);
    245 	if (filled)
    246 		XFillRectangle(drw->dpy, drw->drawable, drw->gc, x, y, w, h);
    247 	else
    248 		XDrawRectangle(drw->dpy, drw->drawable, drw->gc, x, y, w - 1, h - 1);
    249 }
    250 
    251 int
    252 drw_text(Drw *drw, int x, int y, unsigned int w, unsigned int h, unsigned int lpad, const char *text, int invert)
    253 {
    254 	int i, ty, ellipsis_x = 0;
    255 	unsigned int tmpw, ew, ellipsis_w = 0, ellipsis_len;
    256 	XftDraw *d = NULL;
    257 	Fnt *usedfont, *curfont, *nextfont;
    258 	int utf8strlen, utf8charlen, render = x || y || w || h;
    259 	long utf8codepoint = 0;
    260 	const char *utf8str;
    261 	FcCharSet *fccharset;
    262 	FcPattern *fcpattern;
    263 	FcPattern *match;
    264 	XftResult result;
    265 	int charexists = 0, overflow = 0;
    266 	/* keep track of a couple codepoints for which we have no match. */
    267 	enum { nomatches_len = 64 };
    268 	static struct { long codepoint[nomatches_len]; unsigned int idx; } nomatches;
    269 	static unsigned int ellipsis_width = 0;
    270 
    271 	if (!drw || (render && (!drw->scheme || !w)) || !text || !drw->fonts)
    272 		return 0;
    273 
    274 	if (!render) {
    275 		w = invert ? invert : ~invert;
    276 	} else {
    277 		XSetForeground(drw->dpy, drw->gc, drw->scheme[invert ? ColFg : ColBg].pixel);
    278 		XFillRectangle(drw->dpy, drw->drawable, drw->gc, x, y, w, h);
    279 		d = XftDrawCreate(drw->dpy, drw->drawable,
    280 		                  DefaultVisual(drw->dpy, drw->screen),
    281 		                  DefaultColormap(drw->dpy, drw->screen));
    282 		x += lpad;
    283 		w -= lpad;
    284 	}
    285 
    286 	usedfont = drw->fonts;
    287 	if (!ellipsis_width && render)
    288 		ellipsis_width = drw_fontset_getwidth(drw, "...");
    289 	while (1) {
    290 		ew = ellipsis_len = utf8strlen = 0;
    291 		utf8str = text;
    292 		nextfont = NULL;
    293 		while (*text) {
    294 			utf8charlen = utf8decode(text, &utf8codepoint, UTF_SIZ);
    295 			for (curfont = drw->fonts; curfont; curfont = curfont->next) {
    296 				charexists = charexists || XftCharExists(drw->dpy, curfont->xfont, utf8codepoint);
    297 				if (charexists) {
    298 					drw_font_getexts(curfont, text, utf8charlen, &tmpw, NULL);
    299 					if (ew + ellipsis_width <= w) {
    300 						/* keep track where the ellipsis still fits */
    301 						ellipsis_x = x + ew;
    302 						ellipsis_w = w - ew;
    303 						ellipsis_len = utf8strlen;
    304 					}
    305 
    306 					if (ew + tmpw > w) {
    307 						overflow = 1;
    308 						/* called from drw_fontset_getwidth_clamp():
    309 						 * it wants the width AFTER the overflow
    310 						 */
    311 						if (!render)
    312 							x += tmpw;
    313 						else
    314 							utf8strlen = ellipsis_len;
    315 					} else if (curfont == usedfont) {
    316 						utf8strlen += utf8charlen;
    317 						text += utf8charlen;
    318 						ew += tmpw;
    319 					} else {
    320 						nextfont = curfont;
    321 					}
    322 					break;
    323 				}
    324 			}
    325 
    326 			if (overflow || !charexists || nextfont)
    327 				break;
    328 			else
    329 				charexists = 0;
    330 		}
    331 
    332 		if (utf8strlen) {
    333 			if (render) {
    334 				ty = y + (h - usedfont->h) / 2 + usedfont->xfont->ascent;
    335 				XftDrawStringUtf8(d, &drw->scheme[invert ? ColBg : ColFg],
    336 				                  usedfont->xfont, x, ty, (XftChar8 *)utf8str, utf8strlen);
    337 			}
    338 			x += ew;
    339 			w -= ew;
    340 		}
    341 		if (render && overflow)
    342 			drw_text(drw, ellipsis_x, y, ellipsis_w, h, 0, "...", invert);
    343 
    344 		if (!*text || overflow) {
    345 			break;
    346 		} else if (nextfont) {
    347 			charexists = 0;
    348 			usedfont = nextfont;
    349 		} else {
    350 			/* Regardless of whether or not a fallback font is found, the
    351 			 * character must be drawn. */
    352 			charexists = 1;
    353 
    354 			for (i = 0; i < nomatches_len; ++i) {
    355 				/* avoid calling XftFontMatch if we know we won't find a match */
    356 				if (utf8codepoint == nomatches.codepoint[i])
    357 					goto no_match;
    358 			}
    359 
    360 			fccharset = FcCharSetCreate();
    361 			FcCharSetAddChar(fccharset, utf8codepoint);
    362 
    363 			if (!drw->fonts->pattern) {
    364 				/* Refer to the comment in xfont_create for more information. */
    365 				die("the first font in the cache must be loaded from a font string.");
    366 			}
    367 
    368 			fcpattern = FcPatternDuplicate(drw->fonts->pattern);
    369 			FcPatternAddCharSet(fcpattern, FC_CHARSET, fccharset);
    370 			FcPatternAddBool(fcpattern, FC_SCALABLE, FcTrue);
    371 			FcPatternAddBool(fcpattern, FC_COLOR, FcFalse);
    372 
    373 			FcConfigSubstitute(NULL, fcpattern, FcMatchPattern);
    374 			FcDefaultSubstitute(fcpattern);
    375 			match = XftFontMatch(drw->dpy, drw->screen, fcpattern, &result);
    376 
    377 			FcCharSetDestroy(fccharset);
    378 			FcPatternDestroy(fcpattern);
    379 
    380 			if (match) {
    381 				usedfont = xfont_create(drw, NULL, match);
    382 				if (usedfont && XftCharExists(drw->dpy, usedfont->xfont, utf8codepoint)) {
    383 					for (curfont = drw->fonts; curfont->next; curfont = curfont->next)
    384 						; /* NOP */
    385 					curfont->next = usedfont;
    386 				} else {
    387 					xfont_free(usedfont);
    388 					nomatches.codepoint[++nomatches.idx % nomatches_len] = utf8codepoint;
    389 no_match:
    390 					usedfont = drw->fonts;
    391 				}
    392 			}
    393 		}
    394 	}
    395 	if (d)
    396 		XftDrawDestroy(d);
    397 
    398 	return x + (render ? w : 0);
    399 }
    400 
    401 void
    402 drw_map(Drw *drw, Window win, int x, int y, unsigned int w, unsigned int h)
    403 {
    404 	if (!drw)
    405 		return;
    406 
    407 	XCopyArea(drw->dpy, drw->drawable, win, drw->gc, x, y, w, h, x, y);
    408 	XSync(drw->dpy, False);
    409 }
    410 
    411 unsigned int
    412 drw_fontset_getwidth(Drw *drw, const char *text)
    413 {
    414 	if (!drw || !drw->fonts || !text)
    415 		return 0;
    416 	return drw_text(drw, 0, 0, 0, 0, 0, text, 0);
    417 }
    418 
    419 unsigned int
    420 drw_fontset_getwidth_clamp(Drw *drw, const char *text, unsigned int n)
    421 {
    422 	unsigned int tmp = 0;
    423 	if (drw && drw->fonts && text && n)
    424 		tmp = drw_text(drw, 0, 0, 0, 0, 0, text, n);
    425 	return MIN(n, tmp);
    426 }
    427 
    428 void
    429 drw_font_getexts(Fnt *font, const char *text, unsigned int len, unsigned int *w, unsigned int *h)
    430 {
    431 	XGlyphInfo ext;
    432 
    433 	if (!font || !text)
    434 		return;
    435 
    436 	XftTextExtentsUtf8(font->dpy, font->xfont, (XftChar8 *)text, len, &ext);
    437 	if (w)
    438 		*w = ext.xOff;
    439 	if (h)
    440 		*h = font->h;
    441 }
    442 
    443 Cur *
    444 drw_cur_create(Drw *drw, int shape)
    445 {
    446 	Cur *cur;
    447 
    448 	if (!drw || !(cur = ecalloc(1, sizeof(Cur))))
    449 		return NULL;
    450 
    451 	cur->cursor = XCreateFontCursor(drw->dpy, shape);
    452 
    453 	return cur;
    454 }
    455 
    456 void
    457 drw_cur_free(Drw *drw, Cur *cursor)
    458 {
    459 	if (!cursor)
    460 		return;
    461 
    462 	XFreeCursor(drw->dpy, cursor->cursor);
    463 	free(cursor);
    464 }