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         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, XftColor *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 Scm
 197 drw_scm_create(Drw *drw, const char *clrnames[], size_t clrcount)
 198 {
 199         size_t i;
 200         Scm 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, Scm 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 }