drw.c

   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 }