src/xrdb.c

   1 /* Deal with the X Resource Manager.
   2    Copyright (C) 1990, 1993-1994, 2000-2013 Free Software Foundation,
   3    Inc.
   4
   5 Author: Joseph Arceneaux
   6 Created: 4/90
   7
   8 This file is part of GNU Emacs.
   9
  10 GNU Emacs is free software: you can redistribute it and/or modify
  11 it under the terms of the GNU General Public License as published by
  12 the Free Software Foundation, either version 3 of the License, or
  13 (at your option) any later version.
  14
  15 GNU Emacs is distributed in the hope that it will be useful,
  16 but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18 GNU General Public License for more details.
  19
  20 You should have received a copy of the GNU General Public License
  21 along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
  22
  23 #include <config.h>
  24
  25 #include <unistd.h>
  26 #include <errno.h>
  27 #include <epaths.h>
  28 #include <stdlib.h>
  29 #include <stdio.h>
  30
  31 #include "lisp.h"
  32
  33 /* This may include sys/types.h, and that somehow loses
  34    if this is not done before the other system files.  */
  35 #include "xterm.h"
  36
  37 #include <X11/Xlib.h>
  38 #include <X11/Xatom.h>
  39 #include <X11/X.h>
  40 #include <X11/Xutil.h>
  41 #include <X11/Xresource.h>
  42 #ifdef HAVE_PWD_H
  43 #include <pwd.h>
  44 #endif
  45
  46 #ifdef USE_MOTIF
  47 /* For Vdouble_click_time.  */
  48 #include "keyboard.h"
  49 #endif
  50
  51 char *x_get_string_resource (XrmDatabase rdb, const char *name,
  52                              const char *class);
  53
  54 \f
  55 /* X file search path processing.  */
  56
  57
  58 /* The string which gets substituted for the %C escape in XFILESEARCHPATH
  59    and friends, or zero if none was specified.  */
  60 static char *x_customization_string;
  61
  62
  63 /* Return the value of the emacs.customization (Emacs.Customization)
  64    resource, for later use in search path decoding.  If we find no
  65    such resource, return zero.  */
  66 static char *
  67 x_get_customization_string (XrmDatabase db, const char *name,
  68                             const char *class)
  69 {
  70   char *full_name = alloca (strlen (name) + sizeof "customization" + 3);
  71   char *full_class = alloca (strlen (class) + sizeof "Customization" + 3);
  72   char *result;
  73
  74   sprintf (full_name,  "%s.%s", name,  "customization");
  75   sprintf (full_class, "%s.%s", class, "Customization");
  76
  77   result = x_get_string_resource (db, full_name, full_class);
  78   return result ? xstrdup (result) : NULL;
  79 }
  80
  81 /* Expand all the Xt-style %-escapes in STRING, whose length is given
  82    by STRING_LEN.  Here are the escapes we're supposed to recognize:
  83
  84         %N      The value of the application's class name
  85         %T      The value of the type parameter ("app-defaults" in this
  86                 context)
  87         %S      The value of the suffix parameter ("" in this context)
  88         %L      The language string associated with the specified display
  89                 (We use the "LANG" environment variable here, if it's set.)
  90         %l      The language part of the display's language string
  91                 (We treat this just like %L.  If someone can tell us what
  92                  we're really supposed to do, dandy.)
  93         %t      The territory part of the display's language string
  94                 (This never gets used.)
  95         %c      The codeset part of the display's language string
  96                 (This never gets used either.)
  97         %C      The customization string retrieved from the resource
  98                 database associated with display.
  99                 (This is x_customization_string.)
 100
 101    Return the resource database if its file was read successfully, and
 102    refers to %L only when the LANG environment variable is set, or
 103    otherwise provided by X.
 104
 105    ESCAPED_SUFFIX is postpended to STRING if it is non-zero.
 106    %-escapes in ESCAPED_SUFFIX are expanded.
 107
 108    Return NULL otherwise.  */
 109
 110 static XrmDatabase
 111 magic_db (const char *string, ptrdiff_t string_len, const char *class,
 112           const char *escaped_suffix)
 113 {
 114   XrmDatabase db;
 115   char *lang = getenv ("LANG");
 116
 117   ptrdiff_t path_size = 100;
 118   char *path = xmalloc (path_size);
 119   ptrdiff_t path_len = 0;
 120
 121   const char *p = string;
 122
 123   while (p < string + string_len)
 124     {
 125       /* The chunk we're about to stick on the end of result.  */
 126       const char *next = NULL;
 127       ptrdiff_t next_len;
 128
 129       if (*p == '%')
 130         {
 131           p++;
 132
 133           if (p >= string + string_len)
 134             next_len = 0;
 135           else
 136             switch (*p)
 137               {
 138               case '%':
 139                 next = "%";
 140                 next_len = 1;
 141                 break;
 142
 143               case 'C':
 144                 next = (x_customization_string
 145                         ? x_customization_string
 146                         : "");
 147                 next_len = strlen (next);
 148                 break;
 149
 150               case 'N':
 151                 next = class;
 152                 next_len = strlen (class);
 153                 break;
 154
 155               case 'T':
 156                 next = "app-defaults";
 157                 next_len = strlen (next);
 158                 break;
 159
 160               default:
 161               case 'S':
 162                 next_len = 0;
 163                 break;
 164
 165               case 'L':
 166               case 'l':
 167                 if (! lang)
 168                   {
 169                     xfree (path);
 170                     return NULL;
 171                   }
 172
 173                 next = lang;
 174                 next_len = strlen (next);
 175                 break;
 176
 177               case 't':
 178               case 'c':
 179                 xfree (path);
 180                 return NULL;
 181               }
 182         }
 183       else
 184         next = p, next_len = 1;
 185
 186       /* Do we have room for this component followed by a '\0' ?  */
 187       if (path_size - path_len <= next_len)
 188         {
 189           if (min (PTRDIFF_MAX, SIZE_MAX) / 2 - 1 - path_len < next_len)
 190             memory_full (SIZE_MAX);
 191           path_size = (path_len + next_len + 1) * 2;
 192           path = xrealloc (path, path_size);
 193         }
 194
 195       memcpy (path + path_len, next, next_len);
 196       path_len += next_len;
 197
 198       p++;
 199
 200       /* If we've reached the end of the string, append ESCAPED_SUFFIX.  */
 201       if (p >= string + string_len && escaped_suffix)
 202         {
 203           string = escaped_suffix;
 204           string_len = strlen (string);
 205           p = string;
 206           escaped_suffix = NULL;
 207         }
 208     }
 209
 210   path[path_len] = '\0';
 211   db = XrmGetFileDatabase (path);
 212   xfree (path);
 213   return db;
 214 }
 215
 216
 217 static char *
 218 gethomedir (void)
 219 {
 220   struct passwd *pw;
 221   char *ptr;
 222   char *copy;
 223
 224   if ((ptr = getenv ("HOME")) == NULL)
 225     {
 226       if ((ptr = getenv ("LOGNAME")) != NULL
 227           || (ptr = getenv ("USER")) != NULL)
 228         pw = getpwnam (ptr);
 229       else
 230         pw = getpwuid (getuid ());
 231
 232       if (pw)
 233         ptr = pw->pw_dir;
 234     }
 235
 236   if (ptr == NULL)
 237     return xstrdup ("/");
 238
 239   copy = xmalloc (strlen (ptr) + 2);
 240   strcpy (copy, ptr);
 241   strcat (copy, "/");
 242
 243   return copy;
 244 }
 245
 246
 247 /* Find the first element of SEARCH_PATH which exists and is readable,
 248    after expanding the %-escapes.  Return 0 if we didn't find any, and
 249    the path name of the one we found otherwise.  */
 250
 251 static XrmDatabase
 252 search_magic_path (const char *search_path, const char *class,
 253                    const char *escaped_suffix)
 254 {
 255   const char *s, *p;
 256
 257   for (s = search_path; *s; s = p)
 258     {
 259       for (p = s; *p && *p != ':'; p++)
 260         ;
 261
 262       if (p > s)
 263         {
 264           XrmDatabase db = magic_db (s, p - s, class, escaped_suffix);
 265           if (db)
 266             return db;
 267         }
 268       else if (*p == ':')
 269         {
 270           static char const ns[] = "%N%S";
 271           XrmDatabase db = magic_db (ns, strlen (ns), class, escaped_suffix);
 272           if (db)
 273             return db;
 274         }
 275
 276       if (*p == ':')
 277         p++;
 278     }
 279
 280   return 0;
 281 }
 282 \f
 283 /* Producing databases for individual sources.  */
 284
 285 static XrmDatabase
 286 get_system_app (const char *class)
 287 {
 288   const char *path;
 289
 290   path = getenv ("XFILESEARCHPATH");
 291   if (! path) path = PATH_X_DEFAULTS;
 292
 293   return search_magic_path (path, class, 0);
 294 }
 295
 296
 297 static XrmDatabase
 298 get_fallback (Display *display)
 299 {
 300   return NULL;
 301 }
 302
 303
 304 static XrmDatabase
 305 get_user_app (const char *class)
 306 {
 307   XrmDatabase db = 0;
 308   const char *path;
 309
 310   /* Check for XUSERFILESEARCHPATH.  It is a path of complete file
 311      names, not directories.  */
 312   path = getenv ("XUSERFILESEARCHPATH");
 313   if (path)
 314     db = search_magic_path (path, class, 0);
 315
 316   if (! db)
 317     {
 318       /* Check for APPLRESDIR; it is a path of directories.  In each,
 319          we have to search for LANG/CLASS and then CLASS.  */
 320       path = getenv ("XAPPLRESDIR");
 321       if (path)
 322         {
 323           db = search_magic_path (path, class, "/%L/%N");
 324           if (!db)
 325             db = search_magic_path (path, class, "/%N");
 326         }
 327     }
 328
 329   if (! db)
 330     {
 331       /* Check in the home directory.  This is a bit of a hack; let's
 332          hope one's home directory doesn't contain any %-escapes.  */
 333       char *home = gethomedir ();
 334       db = search_magic_path (home, class, "%L/%N");
 335       if (! db)
 336         db = search_magic_path (home, class, "%N");
 337       xfree (home);
 338     }
 339
 340   return db;
 341 }
 342
 343
 344 static XrmDatabase
 345 get_user_db (Display *display)
 346 {
 347   XrmDatabase db;
 348   char *xdefs;
 349
 350 #ifdef PBaseSize                /* Cheap way to test for X11R4 or later.  */
 351   xdefs = XResourceManagerString (display);
 352 #else
 353   xdefs = display->xdefaults;
 354 #endif
 355
 356   if (xdefs != NULL)
 357     db = XrmGetStringDatabase (xdefs);
 358   else
 359     {
 360       char *home;
 361       char *xdefault;
 362
 363       home = gethomedir ();
 364       xdefault = xmalloc (strlen (home) + sizeof ".Xdefaults");
 365       strcpy (xdefault, home);
 366       strcat (xdefault, ".Xdefaults");
 367       db = XrmGetFileDatabase (xdefault);
 368       xfree (home);
 369       xfree (xdefault);
 370     }
 371
 372 #ifdef HAVE_XSCREENRESOURCESTRING
 373   /* Get the screen-specific resources too.  */
 374   xdefs = XScreenResourceString (DefaultScreenOfDisplay (display));
 375   if (xdefs != NULL)
 376     {
 377       XrmMergeDatabases (XrmGetStringDatabase (xdefs), &db);
 378       XFree (xdefs);
 379     }
 380 #endif
 381
 382   return db;
 383 }
 384
 385 static XrmDatabase
 386 get_environ_db (void)
 387 {
 388   XrmDatabase db;
 389   char *p;
 390   char *path = 0;
 391
 392   if ((p = getenv ("XENVIRONMENT")) == NULL)
 393     {
 394       static char const xdefaults[] = ".Xdefaults-";
 395       char *home = gethomedir ();
 396       char const *host = SSDATA (Vsystem_name);
 397       ptrdiff_t pathsize = (strlen (home) + sizeof xdefaults
 398                             + SBYTES (Vsystem_name));
 399       path = xrealloc (home, pathsize);
 400       strcat (strcat (path, xdefaults), host);
 401       p = path;
 402     }
 403
 404   db = XrmGetFileDatabase (p);
 405
 406   xfree (path);
 407
 408   return db;
 409 }
 410 \f
 411 /* External interface.  */
 412
 413 /* Types of values that we can find in a database */
 414
 415 #define XrmStringType "String"  /* String representation */
 416 static XrmRepresentation x_rm_string;   /* Quark representation */
 417
 418 /* Load X resources based on the display and a possible -xrm option. */
 419
 420 XrmDatabase
 421 x_load_resources (Display *display, const char *xrm_string,
 422                   const char *myname, const char *myclass)
 423 {
 424   XrmDatabase user_database;
 425   XrmDatabase rdb;
 426   XrmDatabase db;
 427   char line[256];
 428
 429 #if defined USE_MOTIF || !defined HAVE_XFT || !defined USE_LUCID
 430   const char *helv = "-*-helvetica-medium-r-*--*-120-*-*-*-*-iso8859-1";
 431 #endif
 432
 433 #ifdef USE_MOTIF
 434   const char *courier = "-*-courier-medium-r-*-*-*-120-*-*-*-*-iso8859-1";
 435 #endif
 436
 437   x_rm_string = XrmStringToQuark (XrmStringType);
 438 #ifndef USE_X_TOOLKIT
 439   /* pmr@osf.org says this shouldn't be done if USE_X_TOOLKIT.
 440      I suspect it's because the toolkit version does this elsewhere.  */
 441   XrmInitialize ();
 442 #endif
 443   rdb = XrmGetStringDatabase ("");
 444
 445   /* Add some font defaults.  If the font `helv' doesn't exist, widgets
 446      will use some other default font.  */
 447 #ifdef USE_MOTIF
 448
 449   sprintf (line, "%s.pane.background: grey75", myclass);
 450   XrmPutLineResource (&rdb, line);
 451   sprintf (line, "%s*fontList: %s", myclass, helv);
 452   XrmPutLineResource (&rdb, line);
 453   sprintf (line, "%s*menu*background: grey75", myclass);
 454   XrmPutLineResource (&rdb, line);
 455   sprintf (line, "%s*menubar*background: grey75", myclass);
 456   XrmPutLineResource (&rdb, line);
 457   sprintf (line, "%s*verticalScrollBar.background: grey75", myclass);
 458   XrmPutLineResource (&rdb, line);
 459   sprintf (line, "%s*verticalScrollBar.troughColor: grey75", myclass);
 460   XrmPutLineResource (&rdb, line);
 461   sprintf (line, "%s.dialog*.background: grey75", myclass);
 462   XrmPutLineResource (&rdb, line);
 463   sprintf (line, "%s*fsb.Text.background: white", myclass);
 464   XrmPutLineResource (&rdb, line);
 465   sprintf (line, "%s*fsb.FilterText.background: white", myclass);
 466   XrmPutLineResource (&rdb, line);
 467   sprintf (line, "%s*fsb*DirList.background: white", myclass);
 468   XrmPutLineResource (&rdb, line);
 469   sprintf (line, "%s*fsb*ItemsList.background: white", myclass);
 470   XrmPutLineResource (&rdb, line);
 471   sprintf (line, "%s*fsb*background: grey75", myclass);
 472   XrmPutLineResource (&rdb, line);
 473   sprintf (line, "%s*fsb.Text.fontList: %s", myclass, courier);
 474   XrmPutLineResource (&rdb, line);
 475   sprintf (line, "%s*fsb.FilterText.fontList: %s", myclass, courier);
 476   XrmPutLineResource (&rdb, line);
 477   sprintf (line, "%s*fsb*ItemsList.fontList: %s", myclass, courier);
 478   XrmPutLineResource (&rdb, line);
 479   sprintf (line, "%s*fsb*DirList.fontList: %s", myclass, courier);
 480   XrmPutLineResource (&rdb, line);
 481
 482   /* Set double click time of list boxes in the file selection
 483      dialog from `double-click-time'.  */
 484   if (INTEGERP (Vdouble_click_time) && XINT (Vdouble_click_time) > 0)
 485     {
 486       sprintf (line, "%s*fsb*DirList.doubleClickInterval: %"pI"d",
 487                myclass, XFASTINT (Vdouble_click_time));
 488       XrmPutLineResource (&rdb, line);
 489       sprintf (line, "%s*fsb*ItemsList.doubleClickInterval: %"pI"d",
 490                myclass, XFASTINT (Vdouble_click_time));
 491       XrmPutLineResource (&rdb, line);
 492     }
 493
 494 #else /* not USE_MOTIF */
 495
 496   sprintf (line, "Emacs.dialog*.background: grey75");
 497   XrmPutLineResource (&rdb, line);
 498 #if !defined (HAVE_XFT) || !defined (USE_LUCID)
 499   sprintf (line, "Emacs.dialog*.font: %s", helv);
 500   XrmPutLineResource (&rdb, line);
 501   sprintf (line, "*XlwMenu*font: %s", helv);
 502   XrmPutLineResource (&rdb, line);
 503 #endif
 504   sprintf (line, "*XlwMenu*background: grey75");
 505   XrmPutLineResource (&rdb, line);
 506   sprintf (line, "Emacs*verticalScrollBar.background: grey75");
 507   XrmPutLineResource (&rdb, line);
 508
 509 #endif /* not USE_MOTIF */
 510
 511   user_database = get_user_db (display);
 512
 513   /* Figure out what the "customization string" is, so we can use it
 514      to decode paths.  */
 515   xfree (x_customization_string);
 516   x_customization_string
 517     = x_get_customization_string (user_database, myname, myclass);
 518
 519   /* Get application system defaults */
 520   db = get_system_app (myclass);
 521   if (db != NULL)
 522     XrmMergeDatabases (db, &rdb);
 523
 524   /* Get Fallback resources */
 525   db = get_fallback (display);
 526   if (db != NULL)
 527     XrmMergeDatabases (db, &rdb);
 528
 529   /* Get application user defaults */
 530   db = get_user_app (myclass);
 531   if (db != NULL)
 532     XrmMergeDatabases (db, &rdb);
 533
 534   /* get User defaults */
 535   if (user_database != NULL)
 536     XrmMergeDatabases (user_database, &rdb);
 537
 538   /* Get Environment defaults. */
 539   db = get_environ_db ();
 540   if (db != NULL)
 541     XrmMergeDatabases (db, &rdb);
 542
 543   /* Last, merge in any specification from the command line. */
 544   if (xrm_string != NULL)
 545     {
 546       db = XrmGetStringDatabase (xrm_string);
 547       if (db != NULL)
 548         XrmMergeDatabases (db, &rdb);
 549     }
 550
 551   return rdb;
 552 }
 553
 554
 555 /* Retrieve the value of the resource specified by NAME with class CLASS
 556    and of type TYPE from database RDB.  The value is returned in RET_VALUE. */
 557
 558 static int
 559 x_get_resource (XrmDatabase rdb, const char *name, const char *class,
 560                 XrmRepresentation expected_type, XrmValue *ret_value)
 561 {
 562   XrmValue value;
 563   XrmName namelist[100];
 564   XrmClass classlist[100];
 565   XrmRepresentation type;
 566
 567   XrmStringToNameList (name, namelist);
 568   XrmStringToClassList (class, classlist);
 569
 570   if (XrmQGetResource (rdb, namelist, classlist, &type, &value) == True
 571       && (type == expected_type))
 572     {
 573       if (type == x_rm_string)
 574         ret_value->addr = (char *) value.addr;
 575       else
 576         memcpy (ret_value->addr, value.addr, ret_value->size);
 577
 578       return value.size;
 579     }
 580
 581   return 0;
 582 }
 583
 584 /* Retrieve the string resource specified by NAME with CLASS from
 585    database RDB. */
 586
 587 char *
 588 x_get_string_resource (XrmDatabase rdb, const char *name, const char *class)
 589 {
 590   XrmValue value;
 591
 592   if (inhibit_x_resources)
 593     /* --quick was passed, so this is a no-op.  */
 594     return NULL;
 595
 596   if (x_get_resource (rdb, name, class, x_rm_string, &value))
 597     return (char *) value.addr;
 598
 599   return 0;
 600 }
 601 \f
 602 /* Stand-alone test facilities.  */
 603
 604 #ifdef TESTRM
 605
 606 typedef char **List;
 607 #define arg_listify(len, list) (list)
 608 #define car(list) (*(list))
 609 #define cdr(list) (list + 1)
 610 #define NIL(list) (! *(list))
 611 #define free_arglist(list)
 612
 613 static List
 614 member (char *elt, List list)
 615 {
 616   List p;
 617
 618   for (p = list; ! NIL (p); p = cdr (p))
 619     if (! strcmp (elt, car (p)))
 620       return p;
 621
 622   return p;
 623 }
 624
 625 static void
 626 fatal (char *msg, char *prog)
 627 {
 628   fprintf (stderr, msg, prog);
 629   exit (1);
 630 }
 631
 632 int
 633 main (int argc, char **argv)
 634 {
 635   Display *display;
 636   char *displayname, *resource_string, *class, *name;
 637   XrmDatabase xdb;
 638   List arg_list, lp;
 639
 640   arg_list = arg_listify (argc, argv);
 641
 642   lp = member ("-d", arg_list);
 643   if (!NIL (lp))
 644     displayname = car (cdr (lp));
 645   else
 646     displayname = "localhost:0.0";
 647
 648   lp = member ("-xrm", arg_list);
 649   resource_string = NIL (lp) ? 0 : car (cdr (lp));
 650
 651   lp = member ("-c", arg_list);
 652   if (! NIL (lp))
 653     class = car (cdr (lp));
 654   else
 655     class = "Emacs";
 656
 657   lp = member ("-n", arg_list);
 658   if (! NIL (lp))
 659     name = car (cdr (lp));
 660   else
 661     name = "emacs";
 662
 663   free_arglist (arg_list);
 664
 665   if (!(display = XOpenDisplay (displayname)))
 666     fatal ("Can't open display '%s'\n", XDisplayName (displayname));
 667
 668   xdb = x_load_resources (display, resource_string, name, class);
 669
 670   /* In a real program, you'd want to also do this: */
 671   display->db = xdb;
 672
 673   while (1)
 674     {
 675       char query_name[90];
 676       char query_class[90];
 677
 678       printf ("Name: ");
 679       gets (query_name);
 680
 681       if (strlen (query_name))
 682         {
 683           char *value;
 684
 685           printf ("Class: ");
 686           gets (query_class);
 687
 688           value = x_get_string_resource (xdb, query_name, query_class);
 689
 690           if (value != NULL)
 691             printf ("\t%s(%s):  %s\n\n", query_name, query_class, value);
 692           else
 693             printf ("\tNo Value.\n\n");
 694         }
 695       else
 696         break;
 697     }
 698   printf ("\tExit.\n\n");
 699
 700   XCloseDisplay (display);
 701
 702   return 0;
 703 }
 704 #endif /* TESTRM */