sent

simple plaintext presentation tool
git clone git://git.suckless.org/sent
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drw.c (9896B)

      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 	free(drw);
     99 }
    100 
    101 /* This function is an implementation detail. Library users should use
    102  * drw_fontset_create instead.
    103  */
    104 static Fnt *
    105 xfont_create(Drw *drw, const char *fontname, FcPattern *fontpattern)
    106 {
    107 	Fnt *font;
    108 	XftFont *xfont = NULL;
    109 	FcPattern *pattern = NULL;
    110 
    111 	if (fontname) {
    112 		/* Using the pattern found at font->xfont->pattern does not yield the
    113 		 * same substitution results as using the pattern returned by
    114 		 * FcNameParse; using the latter results in the desired fallback
    115 		 * behaviour whereas the former just results in missing-character
    116 		 * rectangles being drawn, at least with some fonts. */
    117 		if (!(xfont = XftFontOpenName(drw->dpy, drw->screen, fontname))) {
    118 			fprintf(stderr, "error, cannot load font from name: '%s'\n", fontname);
    119 			return NULL;
    120 		}
    121 		if (!(pattern = FcNameParse((FcChar8 *) fontname))) {
    122 			fprintf(stderr, "error, cannot parse font name to pattern: '%s'\n", fontname);
    123 			XftFontClose(drw->dpy, xfont);
    124 			return NULL;
    125 		}
    126 	} else if (fontpattern) {
    127 		if (!(xfont = XftFontOpenPattern(drw->dpy, fontpattern))) {
    128 			fprintf(stderr, "error, cannot load font from pattern.\n");
    129 			return NULL;
    130 		}
    131 	} else {
    132 		die("no font specified.");
    133 	}
    134 
    135 	font = ecalloc(1, sizeof(Fnt));
    136 	font->xfont = xfont;
    137 	font->pattern = pattern;
    138 	font->h = xfont->ascent + xfont->descent;
    139 	font->dpy = drw->dpy;
    140 
    141 	return font;
    142 }
    143 
    144 static void
    145 xfont_free(Fnt *font)
    146 {
    147 	if (!font)
    148 		return;
    149 	if (font->pattern)
    150 		FcPatternDestroy(font->pattern);
    151 	XftFontClose(font->dpy, font->xfont);
    152 	free(font);
    153 }
    154 
    155 Fnt*
    156 drw_fontset_create(Drw* drw, const char *fonts[], size_t fontcount)
    157 {
    158 	Fnt *cur, *ret = NULL;
    159 	size_t i;
    160 
    161 	if (!drw || !fonts)
    162 		return NULL;
    163 
    164 	for (i = 1; i <= fontcount; i++) {
    165 		if ((cur = xfont_create(drw, fonts[fontcount - i], NULL))) {
    166 			cur->next = ret;
    167 			ret = cur;
    168 		}
    169 	}
    170 	return (drw->fonts = ret);
    171 }
    172 
    173 void
    174 drw_fontset_free(Fnt *font)
    175 {
    176 	if (font) {
    177 		drw_fontset_free(font->next);
    178 		xfont_free(font);
    179 	}
    180 }
    181 
    182 void
    183 drw_clr_create(Drw *drw, Clr *dest, const char *clrname)
    184 {
    185 	if (!drw || !dest || !clrname)
    186 		return;
    187 
    188 	if (!XftColorAllocName(drw->dpy, DefaultVisual(drw->dpy, drw->screen),
    189 	                       DefaultColormap(drw->dpy, drw->screen),
    190 	                       clrname, dest))
    191 		die("error, cannot allocate color '%s'", clrname);
    192 }
    193 
    194 /* Wrapper to create color schemes. The caller has to call free(3) on the
    195  * returned color scheme when done using it. */
    196 Clr *
    197 drw_scm_create(Drw *drw, const char *clrnames[], size_t clrcount)
    198 {
    199 	size_t i;
    200 	Clr *ret;
    201 
    202 	/* need at least two colors for a scheme */
    203 	if (!drw || !clrnames || clrcount < 2 || !(ret = ecalloc(clrcount, sizeof(XftColor))))
    204 		return NULL;
    205 
    206 	for (i = 0; i < clrcount; i++)
    207 		drw_clr_create(drw, &ret[i], clrnames[i]);
    208 	return ret;
    209 }
    210 
    211 void
    212 drw_setfontset(Drw *drw, Fnt *set)
    213 {
    214 	if (drw)
    215 		drw->fonts = set;
    216 }
    217 
    218 void
    219 drw_setscheme(Drw *drw, Clr *scm)
    220 {
    221 	if (drw)
    222 		drw->scheme = scm;
    223 }
    224 
    225 void
    226 drw_rect(Drw *drw, int x, int y, unsigned int w, unsigned int h, int filled, int invert)
    227 {
    228 	if (!drw || !drw->scheme)
    229 		return;
    230 	XSetForeground(drw->dpy, drw->gc, invert ? drw->scheme[ColBg].pixel : drw->scheme[ColFg].pixel);
    231 	if (filled)
    232 		XFillRectangle(drw->dpy, drw->drawable, drw->gc, x, y, w, h);
    233 	else
    234 		XDrawRectangle(drw->dpy, drw->drawable, drw->gc, x, y, w - 1, h - 1);
    235 }
    236 
    237 int
    238 drw_text(Drw *drw, int x, int y, unsigned int w, unsigned int h, unsigned int lpad, const char *text, int invert)
    239 {
    240 	char buf[1024];
    241 	int ty;
    242 	unsigned int ew;
    243 	XftDraw *d = NULL;
    244 	Fnt *usedfont, *curfont, *nextfont;
    245 	size_t i, len;
    246 	int utf8strlen, utf8charlen, render = x || y || w || h;
    247 	long utf8codepoint = 0;
    248 	const char *utf8str;
    249 	FcCharSet *fccharset;
    250 	FcPattern *fcpattern;
    251 	FcPattern *match;
    252 	XftResult result;
    253 	int charexists = 0;
    254 
    255 	if (!drw || (render && !drw->scheme) || !text || !drw->fonts)
    256 		return 0;
    257 
    258 	if (!render) {
    259 		w = ~w;
    260 	} else {
    261 		XSetForeground(drw->dpy, drw->gc, drw->scheme[invert ? ColFg : ColBg].pixel);
    262 		XFillRectangle(drw->dpy, drw->drawable, drw->gc, x, y, w, h);
    263 		d = XftDrawCreate(drw->dpy, drw->drawable,
    264 		                  DefaultVisual(drw->dpy, drw->screen),
    265 		                  DefaultColormap(drw->dpy, drw->screen));
    266 		x += lpad;
    267 		w -= lpad;
    268 	}
    269 
    270 	usedfont = drw->fonts;
    271 	while (1) {
    272 		utf8strlen = 0;
    273 		utf8str = text;
    274 		nextfont = NULL;
    275 		while (*text) {
    276 			utf8charlen = utf8decode(text, &utf8codepoint, UTF_SIZ);
    277 			for (curfont = drw->fonts; curfont; curfont = curfont->next) {
    278 				charexists = charexists || XftCharExists(drw->dpy, curfont->xfont, utf8codepoint);
    279 				if (charexists) {
    280 					if (curfont == usedfont) {
    281 						utf8strlen += utf8charlen;
    282 						text += utf8charlen;
    283 					} else {
    284 						nextfont = curfont;
    285 					}
    286 					break;
    287 				}
    288 			}
    289 
    290 			if (!charexists || nextfont)
    291 				break;
    292 			else
    293 				charexists = 0;
    294 		}
    295 
    296 		if (utf8strlen) {
    297 			drw_font_getexts(usedfont, utf8str, utf8strlen, &ew, NULL);
    298 			/* shorten text if necessary */
    299 			for (len = MIN(utf8strlen, sizeof(buf) - 1); len && ew > w; len--)
    300 				drw_font_getexts(usedfont, utf8str, len, &ew, NULL);
    301 
    302 			if (len) {
    303 				memcpy(buf, utf8str, len);
    304 				buf[len] = '\0';
    305 				if (len < utf8strlen)
    306 					for (i = len; i && i > len - 3; buf[--i] = '.')
    307 						; /* NOP */
    308 
    309 				if (render) {
    310 					ty = y + (h - usedfont->h) / 2 + usedfont->xfont->ascent;
    311 					XftDrawStringUtf8(d, &drw->scheme[invert ? ColBg : ColFg],
    312 					                  usedfont->xfont, x, ty, (XftChar8 *)buf, len);
    313 				}
    314 				x += ew;
    315 				w -= ew;
    316 			}
    317 		}
    318 
    319 		if (!*text) {
    320 			break;
    321 		} else if (nextfont) {
    322 			charexists = 0;
    323 			usedfont = nextfont;
    324 		} else {
    325 			/* Regardless of whether or not a fallback font is found, the
    326 			 * character must be drawn. */
    327 			charexists = 1;
    328 
    329 			fccharset = FcCharSetCreate();
    330 			FcCharSetAddChar(fccharset, utf8codepoint);
    331 
    332 			if (!drw->fonts->pattern) {
    333 				/* Refer to the comment in xfont_create for more information. */
    334 				die("the first font in the cache must be loaded from a font string.");
    335 			}
    336 
    337 			fcpattern = FcPatternDuplicate(drw->fonts->pattern);
    338 			FcPatternAddCharSet(fcpattern, FC_CHARSET, fccharset);
    339 			FcPatternAddBool(fcpattern, FC_SCALABLE, FcTrue);
    340 
    341 			FcConfigSubstitute(NULL, fcpattern, FcMatchPattern);
    342 			FcDefaultSubstitute(fcpattern);
    343 			match = XftFontMatch(drw->dpy, drw->screen, fcpattern, &result);
    344 
    345 			FcCharSetDestroy(fccharset);
    346 			FcPatternDestroy(fcpattern);
    347 
    348 			if (match) {
    349 				usedfont = xfont_create(drw, NULL, match);
    350 				if (usedfont && XftCharExists(drw->dpy, usedfont->xfont, utf8codepoint)) {
    351 					for (curfont = drw->fonts; curfont->next; curfont = curfont->next)
    352 						; /* NOP */
    353 					curfont->next = usedfont;
    354 				} else {
    355 					xfont_free(usedfont);
    356 					usedfont = drw->fonts;
    357 				}
    358 			}
    359 		}
    360 	}
    361 	if (d)
    362 		XftDrawDestroy(d);
    363 
    364 	return x + (render ? w : 0);
    365 }
    366 
    367 void
    368 drw_map(Drw *drw, Window win, int x, int y, unsigned int w, unsigned int h)
    369 {
    370 	if (!drw)
    371 		return;
    372 
    373 	XCopyArea(drw->dpy, drw->drawable, win, drw->gc, x, y, w, h, x, y);
    374 	XSync(drw->dpy, False);
    375 }
    376 
    377 unsigned int
    378 drw_fontset_getwidth(Drw *drw, const char *text)
    379 {
    380 	if (!drw || !drw->fonts || !text)
    381 		return 0;
    382 	return drw_text(drw, 0, 0, 0, 0, 0, text, 0);
    383 }
    384 
    385 void
    386 drw_font_getexts(Fnt *font, const char *text, unsigned int len, unsigned int *w, unsigned int *h)
    387 {
    388 	XGlyphInfo ext;
    389 
    390 	if (!font || !text)
    391 		return;
    392 
    393 	XftTextExtentsUtf8(font->dpy, font->xfont, (XftChar8 *)text, len, &ext);
    394 	if (w)
    395 		*w = ext.xOff;
    396 	if (h)
    397 		*h = font->h;
    398 }
    399 
    400 Cur *
    401 drw_cur_create(Drw *drw, int shape)
    402 {
    403 	Cur *cur;
    404 
    405 	if (!drw || !(cur = ecalloc(1, sizeof(Cur))))
    406 		return NULL;
    407 
    408 	cur->cursor = XCreateFontCursor(drw->dpy, shape);
    409 
    410 	return cur;
    411 }
    412 
    413 void
    414 drw_cur_free(Drw *drw, Cur *cursor)
    415 {
    416 	if (!cursor)
    417 		return;
    418 
    419 	XFreeCursor(drw->dpy, cursor->cursor);
    420 	free(cursor);
    421 }