src/xsettings.c

   1 /* Functions for handle font changes dynamically.
   2    Copyright (C) 2009
   3                  Free Software Foundation, Inc.
   4
   5 This file is part of GNU Emacs.
   6
   7 GNU Emacs is free software: you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation, either version 3 of the License, or
  10 (at your option) any later version.
  11
  12 GNU Emacs is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20 #include "config.h"
  21 #include <setjmp.h>
  22 #include <fcntl.h>
  23 #include "lisp.h"
  24 #include "xterm.h"
  25 #include "xsettings.h"
  26 #include "frame.h"
  27 #include "blockinput.h"
  28 #include "termhooks.h"
  29 #include "termopts.h"
  30
  31 #include <X11/Xproto.h>
  32
  33 #ifdef HAVE_GCONF
  34 #include <gconf/gconf-client.h>
  35 #endif
  36 #ifdef HAVE_XFT
  37 #include <X11/Xft/Xft.h>
  38 #endif
  39
  40 static char *current_mono_font;
  41 static struct x_display_info *first_dpyinfo;
  42 static Lisp_Object Qfont_name, Qfont_render;
  43
  44 #ifdef HAVE_GCONF
  45 static GConfClient *gconf_client;
  46 #endif
  47
  48
  49 static void
  50 store_font_changed_event (arg, display_name)
  51      Lisp_Object arg;
  52      Lisp_Object display_name;
  53 {
  54   struct input_event event;
  55   EVENT_INIT (event);
  56   event.kind = CONFIG_CHANGED_EVENT;
  57   event.frame_or_window = display_name;
  58   event.arg = arg;
  59   kbd_buffer_store_event (&event);
  60 }
  61
  62 #ifdef HAVE_GCONF
  63
  64 #define SYSTEM_MONO_FONT       "/desktop/gnome/interface/monospace_font_name"
  65
  66 /* Callback called when something changed in GConf that we care about,
  67    that is SYSTEM_MONO_FONT.  */
  68
  69 static void
  70 something_changedCB (client, cnxn_id, entry, user_data)
  71      GConfClient *client;
  72      guint cnxn_id;
  73      GConfEntry *entry;
  74      gpointer user_data;
  75 {
  76   GConfValue *v = gconf_entry_get_value (entry);
  77
  78   if (!v) return;
  79   if (v->type == GCONF_VALUE_STRING)
  80     {
  81       const char *value = gconf_value_get_string (v);
  82       int i;
  83       if (current_mono_font != NULL && strcmp (value, current_mono_font) == 0)
  84         return; // No change.
  85
  86       xfree (current_mono_font);
  87       current_mono_font = xstrdup (value);
  88     }
  89
  90
  91   if (first_dpyinfo != NULL)
  92     {
  93       /* Check if display still open */
  94       struct x_display_info *dpyinfo;
  95       int found = 0;
  96       for (dpyinfo = x_display_list; !found && dpyinfo; dpyinfo = dpyinfo->next)
  97         found = dpyinfo == first_dpyinfo;
  98
  99       if (found)
 100         store_font_changed_event (Qfont_name,
 101                                   XCAR (first_dpyinfo->name_list_element));
 102     }
 103 }
 104 #endif /* HAVE_GCONF */
 105
 106 #ifdef HAVE_XFT
 107
 108 /* Find the window that contains the XSETTINGS property values.  */
 109
 110 static void
 111 get_prop_window (dpyinfo)
 112      struct x_display_info *dpyinfo;
 113 {
 114   Display *dpy = dpyinfo->display;
 115
 116   XGrabServer (dpy);
 117   dpyinfo->xsettings_window = XGetSelectionOwner (dpy,
 118                                                   dpyinfo->Xatom_xsettings_sel);
 119   if (dpyinfo->xsettings_window != None)
 120     /* Select events so we can detect if window is deleted or if settings
 121        are changed.  */
 122     XSelectInput (dpy, dpyinfo->xsettings_window,
 123                   PropertyChangeMask|StructureNotifyMask);
 124
 125   XUngrabServer (dpy);
 126 }
 127
 128 struct xsettings
 129 {
 130   FcBool aa, hinting;
 131   int rgba, lcdfilter, hintstyle;
 132   double dpi;
 133 };
 134
 135 #define SWAP32(nr) (((nr) << 24) | (((nr) << 8) & 0xff0000)     \
 136                     | (((nr) >> 8) & 0xff00) | ((nr) >> 24))
 137 #define SWAP16(nr) (((nr) << 8) | ((nr) >> 8))
 138 #define PAD(nr)    (((nr) + 3) & ~3)
 139
 140 /* Parse xsettings and extract those that deal with Xft.
 141    See http://freedesktop.org/wiki/Specifications/XSettingsRegistry
 142    and http://standards.freedesktop.org/xsettings-spec/xsettings-spec-0.5.html.
 143
 144    Layout of prop.  First is a header:
 145
 146    bytes   type     what
 147    ------------------------------------
 148    1      CARD8    byte-order
 149    3               unused
 150    4      CARD32   SERIAL
 151    4      CARD32   N_SETTINGS
 152
 153    Then N_SETTINGS records, with header:
 154
 155    bytes   type          what
 156    ------------------------------------
 157    1      SETTING_TYPE  type (0 = integer, 1 = string, 2 RGB color).
 158    1                    unused
 159    2      CARD16        n == name-length
 160    n      STRING8       name
 161    p                    unused, p=pad_to_even_4(n)
 162    4      CARD32        last-change-serial
 163
 164    and then the value, For string:
 165
 166    bytes   type          what
 167    ------------------------------------
 168    4      CARD32        n = value-length
 169    n      STRING8       value
 170    p                    unused, p=pad_to_even_4(n)
 171
 172    For integer:
 173
 174    bytes   type          what
 175    ------------------------------------
 176    4      INT32         value
 177
 178    For RGB color:
 179
 180    bytes   type          what
 181    ------------------------------------
 182    2      CARD16        red
 183    2      CARD16        blue
 184    2      CARD16        green
 185    2      CARD16        alpha
 186
 187 */
 188
 189 static int
 190 parse_xft_settings (prop, bytes, settings)
 191      unsigned char *prop;
 192      unsigned long bytes;
 193      struct xsettings *settings;
 194 {
 195   Lisp_Object byteorder = Fbyteorder ();
 196   int my_bo = XFASTINT (byteorder) == 'B' ? MSBFirst : LSBFirst;
 197   int that_bo = prop[0];
 198   CARD32 n_settings;
 199   int bytes_parsed = 0;
 200   int settings_seen = 0;
 201   int i = 0;
 202
 203   /* First 4 bytes is a serial number, skip that.  */
 204
 205   if (bytes < 12) return BadLength;
 206   memcpy (&n_settings, prop+8, 4);
 207   if (my_bo != that_bo) n_settings = SWAP32 (n_settings);
 208   bytes_parsed = 12;
 209
 210   memset (settings, 0, sizeof (*settings));
 211
 212   while (bytes_parsed+4 < bytes && settings_seen < 6
 213          && i < n_settings)
 214     {
 215       int type = prop[bytes_parsed++];
 216       CARD16 nlen;
 217       CARD32 vlen, ival = 0;
 218       char name[128]; /* The names we are looking for are not this long.  */
 219       char sval[128]; /* The values we are looking for are not this long.  */
 220       int is_xft;
 221       int to_cpy;
 222
 223       sval[0] = '\0';
 224       ++i;
 225       ++bytes_parsed; /* Padding */
 226
 227       memcpy (&nlen, prop+bytes_parsed, 2);
 228       bytes_parsed += 2;
 229       if (my_bo != that_bo) nlen = SWAP16 (nlen);
 230       if (bytes_parsed+nlen > bytes) return BadLength;
 231       to_cpy = nlen > 127 ? 127 : nlen;
 232       memcpy (name, prop+bytes_parsed, to_cpy);
 233       name[to_cpy] = '\0';
 234
 235       bytes_parsed += nlen;
 236       bytes_parsed = PAD (bytes_parsed);
 237
 238       bytes_parsed += 4; /* Skip serial for this value */
 239       if (bytes_parsed > bytes) return BadLength;
 240
 241       is_xft = nlen > 6 && strncmp (name, "Xft/", 4) == 0;
 242
 243       switch (type)
 244         {
 245         case 0: /* Integer */
 246           if (bytes_parsed+4 > bytes) return BadLength;
 247           if (is_xft)
 248             {
 249               memcpy (&ival, prop+bytes_parsed, 4);
 250               if (my_bo != that_bo) ival = SWAP32 (ival);
 251             }
 252           bytes_parsed += 4;
 253           break;
 254
 255         case 1: /* String */
 256           if (bytes_parsed+4 > bytes) return BadLength;
 257           memcpy (&vlen, prop+bytes_parsed, 4);
 258           bytes_parsed += 4;
 259           if (my_bo != that_bo) vlen = SWAP32 (vlen);
 260           if (is_xft)
 261             {
 262               to_cpy = vlen > 127 ? 127 : vlen;
 263               memcpy (sval, prop+bytes_parsed, to_cpy);
 264               sval[to_cpy] = '\0';
 265             }
 266           bytes_parsed += vlen;
 267           bytes_parsed = PAD (bytes_parsed);
 268           break;
 269
 270         case 2: /* RGB value */
 271           /* No need to parse this */
 272           if (bytes_parsed+8 > bytes) return BadLength;
 273           bytes_parsed += 8; /* 4 values (r, b, g, alpha), 2 bytes each.  */
 274           break;
 275
 276         default: /* Parse Error */
 277           return BadValue;
 278         }
 279
 280       if (is_xft)
 281         {
 282           ++settings_seen;
 283           if (strcmp (name, "Xft/Antialias") == 0)
 284             settings->aa = ival != 0;
 285           else if (strcmp (name, "Xft/Hinting") == 0)
 286             settings->hinting = ival != 0;
 287           else if (strcmp (name, "Xft/HintStyle") == 0)
 288             {
 289               if (strcmp (sval, "hintnone") == 0)
 290                 settings->hintstyle = FC_HINT_NONE;
 291               else if (strcmp (sval, "hintslight") == 0)
 292                 settings->hintstyle = FC_HINT_SLIGHT;
 293               else if (strcmp (sval, "hintmedium") == 0)
 294                 settings->hintstyle = FC_HINT_MEDIUM;
 295               else if (strcmp (sval, "hintfull") == 0)
 296                 settings->hintstyle = FC_HINT_FULL;
 297             }
 298           else if (strcmp (name, "Xft/RGBA") == 0)
 299             {
 300               if (strcmp (sval, "none") == 0)
 301                 settings->rgba = FC_RGBA_NONE;
 302               else if (strcmp (sval, "rgb") == 0)
 303                 settings->rgba = FC_RGBA_RGB;
 304               else if (strcmp (sval, "bgr") == 0)
 305                 settings->rgba = FC_RGBA_BGR;
 306               else if (strcmp (sval, "vrgb") == 0)
 307                 settings->rgba = FC_RGBA_VRGB;
 308               else if (strcmp (sval, "vbgr") == 0)
 309                 settings->rgba = FC_RGBA_VBGR;
 310             }
 311           else if (strcmp (name, "Xft/DPI") == 0)
 312             settings->dpi = (double)ival/1024.0;
 313           else if (strcmp (name, "Xft/lcdfilter") == 0)
 314             {
 315               if (strcmp (sval, "none") == 0)
 316                 settings->lcdfilter = FC_LCD_NONE;
 317               else if (strcmp (sval, "lcddefault") == 0)
 318                 settings->lcdfilter = FC_LCD_DEFAULT;
 319             }
 320         }
 321     }
 322
 323   return Success;
 324 }
 325
 326 static int
 327 read_xft_settings (dpyinfo, settings)
 328      struct x_display_info *dpyinfo;
 329      struct xsettings *settings;
 330 {
 331   long long_len;
 332   Atom act_type;
 333   int act_form;
 334   unsigned long nitems, bytes_after;
 335   unsigned char *prop = NULL;
 336   Display *dpy = dpyinfo->display;
 337   int rc;
 338
 339   x_catch_errors (dpy);
 340   rc = XGetWindowProperty (dpy,
 341                            dpyinfo->xsettings_window,
 342                            dpyinfo->Xatom_xsettings_prop,
 343                            0, LONG_MAX, False, AnyPropertyType,
 344                            &act_type, &act_form, &nitems, &bytes_after,
 345                            &prop);
 346
 347   if (rc == Success && prop != NULL && act_form == 8 && nitems > 0
 348       && act_type == dpyinfo->Xatom_xsettings_prop)
 349     rc = parse_xft_settings (prop, nitems, settings);
 350
 351   XFree (prop);
 352
 353   x_uncatch_errors ();
 354
 355   return rc == Success;
 356 }
 357
 358 static void
 359 apply_xft_settings (dpyinfo, send_event_p)
 360      struct x_display_info *dpyinfo;
 361      int send_event_p;
 362 {
 363   FcPattern *pat;
 364   struct xsettings settings, oldsettings;
 365   int changed = 0;
 366
 367   if (!read_xft_settings (dpyinfo, &settings))
 368     return;
 369
 370   memset (&oldsettings, 0, sizeof (oldsettings));
 371
 372   pat = FcPatternCreate ();
 373   XftDefaultSubstitute (dpyinfo->display,
 374                         XScreenNumberOfScreen (dpyinfo->screen),
 375                         pat);
 376   FcPatternGetBool (pat, FC_ANTIALIAS, 0, &oldsettings.aa);
 377   FcPatternGetBool (pat, FC_HINTING, 0, &oldsettings.hinting);
 378   FcPatternGetInteger (pat, FC_HINT_STYLE, 0, &oldsettings.hintstyle);
 379   FcPatternGetInteger (pat, FC_LCD_FILTER, 0, &oldsettings.lcdfilter);
 380   FcPatternGetInteger (pat, FC_RGBA, 0, &oldsettings.rgba);
 381   FcPatternGetDouble (pat, FC_DPI, 0, &oldsettings.dpi);
 382
 383   if (oldsettings.aa != settings.aa)
 384     {
 385       FcPatternDel (pat, FC_ANTIALIAS);
 386       FcPatternAddBool (pat, FC_ANTIALIAS, settings.aa);
 387       ++changed;
 388     }
 389   if (oldsettings.hinting != settings.hinting)
 390     {
 391       FcPatternDel (pat, FC_HINTING);
 392       FcPatternAddBool (pat, FC_HINTING, settings.hinting);
 393       ++changed;
 394     }
 395   if (oldsettings.rgba != settings.rgba)
 396     {
 397       FcPatternDel (pat, FC_RGBA);
 398       FcPatternAddInteger (pat, FC_RGBA, settings.rgba);
 399       ++changed;
 400     }
 401   if (oldsettings.lcdfilter != settings.lcdfilter)
 402     {
 403       FcPatternDel (pat, FC_LCD_FILTER);
 404       FcPatternAddInteger (pat, FC_LCD_FILTER, settings.lcdfilter);
 405       ++changed;
 406     }
 407   if (oldsettings.hintstyle != settings.hintstyle)
 408     {
 409       FcPatternDel (pat, FC_HINT_STYLE);
 410       FcPatternAddInteger (pat, FC_HINT_STYLE, settings.hintstyle);
 411       ++changed;
 412     }
 413   if (oldsettings.dpi != settings.dpi)
 414     {
 415       Lisp_Object frame, tail;
 416
 417       FcPatternDel (pat, FC_DPI);
 418       FcPatternAddDouble (pat, FC_DPI, settings.dpi);
 419       ++changed;
 420
 421       /* Change the DPI on this display and all frames on the display.  */
 422       dpyinfo->resy = dpyinfo->resx = settings.dpi;
 423       FOR_EACH_FRAME (tail, frame)
 424         if (FRAME_X_P (XFRAME (frame))
 425             && FRAME_X_DISPLAY_INFO (XFRAME (frame)) == dpyinfo)
 426           XFRAME (frame)->resy = XFRAME (frame)->resx = settings.dpi;
 427     }
 428
 429   if (changed)
 430     {
 431       XftDefaultSet (dpyinfo->display, pat);
 432       if (send_event_p)
 433         store_font_changed_event (Qfont_render,
 434                                   XCAR (dpyinfo->name_list_element));
 435     }
 436   else
 437     FcPatternDestroy (pat);
 438 }
 439
 440 #endif /* HAVE_XFT */
 441
 442 void
 443 xft_settings_event (dpyinfo, event)
 444      struct x_display_info *dpyinfo;
 445      XEvent *event;
 446 {
 447 #ifdef HAVE_XFT
 448   int check_window_p = 0;
 449
 450   switch (event->type)
 451     {
 452     case DestroyNotify:
 453       if (dpyinfo->xsettings_window == event->xany.window)
 454         check_window_p = 1;
 455       break;
 456
 457     case ClientMessage:
 458       if (event->xclient.message_type == dpyinfo->Xatom_xsettings_mgr
 459           && event->xclient.data.l[1] == dpyinfo->Xatom_xsettings_sel
 460           && event->xclient.window == dpyinfo->root_window)
 461         check_window_p = 1;
 462       break;
 463
 464     case PropertyNotify:
 465       if (event->xproperty.window == dpyinfo->xsettings_window
 466           && event->xproperty.state == PropertyNewValue
 467           && event->xproperty.atom == dpyinfo->Xatom_xsettings_prop)
 468         {
 469           apply_xft_settings (dpyinfo, True);
 470         }
 471       break;
 472     }
 473
 474   if (check_window_p)
 475     {
 476       dpyinfo->xsettings_window = None;
 477       get_prop_window (dpyinfo);
 478       if (dpyinfo->xsettings_window != None)
 479         apply_xft_settings (dpyinfo, True);
 480     }
 481 #endif /* HAVE_XFT */
 482 }
 483
 484
 485 static void
 486 init_gconf ()
 487 {
 488 #ifdef HAVE_GCONF
 489   int i;
 490   char *s;
 491   /* Should be enough, this is called at startup */
 492 #define N_FDS 1024
 493   int fd_before[N_FDS], fd_before1[N_FDS];
 494   int dummy, n_fds;
 495   GPollFD gfds[N_FDS];
 496
 497   /* To find out which filedecriptors GConf uses, check before and after.
 498      If we do not do this, GConf changes will only happen when Emacs gets
 499      an X event.  */
 500   memset (fd_before, 0, sizeof (fd_before));
 501   n_fds = g_main_context_query (g_main_context_default (),
 502                                 G_PRIORITY_LOW,
 503                                 &dummy,
 504                                 gfds,
 505                                 N_FDS);
 506   for (i = 0; i < n_fds; ++i)
 507     if (gfds[i].fd < N_FDS && gfds[i].fd > 0 && gfds[i].events > 0)
 508       fd_before[gfds[i].fd] = 1;
 509
 510   g_type_init ();
 511   gconf_client = gconf_client_get_default ();
 512   s = gconf_client_get_string (gconf_client, SYSTEM_MONO_FONT, NULL);
 513   if (s)
 514     {
 515       current_mono_font = xstrdup (s);
 516       g_free (s);
 517     }
 518   gconf_client_set_error_handling (gconf_client, GCONF_CLIENT_HANDLE_NONE);
 519   gconf_client_add_dir (gconf_client,
 520                         SYSTEM_MONO_FONT,
 521                         GCONF_CLIENT_PRELOAD_ONELEVEL,
 522                         NULL);
 523   gconf_client_notify_add (gconf_client,
 524                            SYSTEM_MONO_FONT,
 525                            something_changedCB,
 526                            NULL, NULL, NULL);
 527   n_fds = g_main_context_query (g_main_context_default (),
 528                                 G_PRIORITY_LOW,
 529                                 &dummy,
 530                                 gfds,
 531                                 N_FDS);
 532
 533   for (i = 0; i < n_fds; ++i)
 534     if (gfds[i].fd < N_FDS && gfds[i].fd > 0 && gfds[i].events > 0
 535         && !fd_before[gfds[i].fd])
 536       {
 537 #ifdef F_SETOWN
 538         fcntl (i, F_SETOWN, getpid ());
 539 #endif /* ! defined (F_SETOWN) */
 540
 541 #ifdef SIGIO
 542         if (interrupt_input)
 543           init_sigio (i);
 544 #endif /* ! defined (SIGIO) */
 545       }
 546 #endif /* HAVE_GCONF */
 547 }
 548
 549 static void
 550 init_xfd_settings (dpyinfo)
 551      struct x_display_info *dpyinfo;
 552 {
 553 #ifdef HAVE_XFT
 554   char sel[64];
 555   Display *dpy = dpyinfo->display;
 556
 557   BLOCK_INPUT;
 558
 559   sprintf (sel, "_XSETTINGS_S%d", XScreenNumberOfScreen (dpyinfo->screen));
 560   dpyinfo->Xatom_xsettings_sel = XInternAtom (dpy, sel, False);
 561   dpyinfo->Xatom_xsettings_prop = XInternAtom (dpy,
 562                                                "_XSETTINGS_SETTINGS",
 563                                                False);
 564   dpyinfo->Xatom_xsettings_mgr = XInternAtom (dpy, "MANAGER", False);
 565
 566   /* Select events so we can detect client messages sent when selection
 567      owner changes.  */
 568   XSelectInput (dpy, dpyinfo->root_window, StructureNotifyMask);
 569
 570   get_prop_window (dpyinfo);
 571   if (dpyinfo->xsettings_window != None)
 572     apply_xft_settings (dpyinfo, False);
 573
 574   UNBLOCK_INPUT;
 575
 576 #else /* ! HAVE_XFT */
 577
 578   dpyinfo->Xatom_xsettings_sel = None;
 579   dpyinfo->Xatom_xsettings_prop = None;
 580   dpyinfo->Xatom_xsettings_mgr = None;
 581   dpyinfo->xsettings_window = None;
 582
 583 #endif /* ! HAVE_XFT */
 584 }
 585
 586 void
 587 xsettings_initialize (dpyinfo)
 588      struct x_display_info *dpyinfo;
 589 {
 590   if (first_dpyinfo == NULL) first_dpyinfo = dpyinfo;
 591   init_gconf ();
 592   init_xfd_settings (dpyinfo);
 593 }
 594
 595
 596 DEFUN ("font-get-system-font", Ffont_get_system_font, Sfont_get_system_font,
 597        0, 0, 0,
 598        doc: /* Get the system default monospaced font. */)
 599   ()
 600 {
 601   return current_mono_font
 602     ? make_string (current_mono_font, strlen (current_mono_font))
 603     : Qnil;
 604 }
 605
 606 void
 607 syms_of_xsettings ()
 608 {
 609   current_mono_font = NULL;
 610   first_dpyinfo = NULL;
 611 #ifdef HAVE_GCONF
 612   gconf_client = NULL;
 613 #endif
 614
 615   Qfont_name = intern_c_string ("font-name");
 616   staticpro (&Qfont_name);
 617   Qfont_render = intern_c_string ("font-render");
 618   staticpro (&Qfont_render);
 619   defsubr (&Sfont_get_system_font);
 620
 621 #ifdef HAVE_GCONF
 622   Fprovide (intern_c_string ("system-font-setting"), Qnil);
 623 #endif
 624 #ifdef HAVE_XFT
 625   Fprovide (intern_c_string ("font-render-setting"), Qnil);
 626 #endif
 627 }