src/xrdb.c

   1 /* Deal with the X Resource Manager.
   2    Copyright (C) 1990, 1993-1994, 2000-2015 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 /* X file search path processing.  */
  52
  53
  54 /* The string which gets substituted for the %C escape in XFILESEARCHPATH
  55    and friends, or zero if none was specified.  */
  56 static char *x_customization_string;
  57
  58
  59 /* Return the value of the emacs.customization (Emacs.Customization)
  60    resource, for later use in search path decoding.  If we find no
  61    such resource, return zero.  */
  62 static char *
  63 x_get_customization_string (XrmDatabase db, const char *name,
  64                             const char *class)
  65 {
  66   char *full_name = alloca (strlen (name) + sizeof "customization" + 3);
  67   char *full_class = alloca (strlen (class) + sizeof "Customization" + 3);
  68   char *result;
  69
  70   sprintf (full_name,  "%s.%s", name,  "customization");
  71   sprintf (full_class, "%s.%s", class, "Customization");
  72
  73   result = x_get_string_resource (db, full_name, full_class);
  74   return result ? xstrdup (result) : NULL;
  75 }
  76
  77 /* Expand all the Xt-style %-escapes in STRING, whose length is given
  78    by STRING_LEN.  Here are the escapes we're supposed to recognize:
  79
  80         %N      The value of the application's class name
  81         %T      The value of the type parameter ("app-defaults" in this
  82                 context)
  83         %S      The value of the suffix parameter ("" in this context)
  84         %L      The language string associated with the specified display
  85                 (We use the "LANG" environment variable here, if it's set.)
  86         %l      The language part of the display's language string
  87                 (We treat this just like %L.  If someone can tell us what
  88                  we're really supposed to do, dandy.)
  89         %t      The territory part of the display's language string
  90                 (This never gets used.)
  91         %c      The codeset part of the display's language string
  92                 (This never gets used either.)
  93         %C      The customization string retrieved from the resource
  94                 database associated with display.
  95                 (This is x_customization_string.)
  96
  97    Return the resource database if its file was read successfully, and
  98    refers to %L only when the LANG environment variable is set, or
  99    otherwise provided by X.
 100
 101    ESCAPED_SUFFIX is postpended to STRING if it is non-zero.
 102    %-escapes in ESCAPED_SUFFIX are expanded.
 103
 104    Return NULL otherwise.  */
 105
 106 static XrmDatabase
 107 magic_db (const char *string, ptrdiff_t string_len, const char *class,
 108           const char *escaped_suffix)
 109 {
 110   XrmDatabase db;
 111   char *lang = getenv ("LANG");
 112
 113   ptrdiff_t path_size = 100;
 114   char *path = xmalloc (path_size);
 115   ptrdiff_t path_len = 0;
 116
 117   const char *p = string;
 118
 119   while (p < string + string_len)
 120     {
 121       /* The chunk we're about to stick on the end of result.  */
 122       const char *next = NULL;
 123       ptrdiff_t next_len;
 124
 125       if (*p == '%')
 126         {
 127           p++;
 128
 129           if (p >= string + string_len)
 130             next_len = 0;
 131           else
 132             switch (*p)
 133               {
 134               case '%':
 135                 next = "%";
 136                 next_len = 1;
 137                 break;
 138
 139               case 'C':
 140                 next = (x_customization_string
 141                         ? x_customization_string
 142                         : "");
 143                 next_len = strlen (next);
 144                 break;
 145
 146               case 'N':
 147                 next = class;
 148                 next_len = strlen (class);
 149                 break;
 150
 151               case 'T':
 152                 next = "app-defaults";
 153                 next_len = strlen (next);
 154                 break;
 155
 156               default:
 157               case 'S':
 158                 next_len = 0;
 159                 break;
 160
 161               case 'L':
 162               case 'l':
 163                 if (! lang)
 164                   {
 165                     xfree (path);
 166                     return NULL;
 167                   }
 168
 169                 next = lang;
 170                 next_len = strlen (next);
 171                 break;
 172
 173               case 't':
 174               case 'c':
 175                 xfree (path);
 176                 return NULL;
 177               }
 178         }
 179       else
 180         next = p, next_len = 1;
 181
 182       /* Do we have room for this component followed by a '\0'?  */
 183       if (path_size - path_len <= next_len)
 184         {
 185           if (min (PTRDIFF_MAX, SIZE_MAX) / 2 - 1 - path_len < next_len)
 186             memory_full (SIZE_MAX);
 187           path_size = (path_len + next_len + 1) * 2;
 188           path = xrealloc (path, path_size);
 189         }
 190
 191       memcpy (path + path_len, next, next_len);
 192       path_len += next_len;
 193
 194       p++;
 195
 196       /* If we've reached the end of the string, append ESCAPED_SUFFIX.  */
 197       if (p >= string + string_len && escaped_suffix)
 198         {
 199           string = escaped_suffix;
 200           string_len = strlen (string);
 201           p = string;
 202           escaped_suffix = NULL;
 203         }
 204     }
 205
 206   path[path_len] = '\0';
 207   db = XrmGetFileDatabase (path);
 208   xfree (path);
 209   return db;
 210 }
 211
 212
 213 static char *
 214 gethomedir (void)
 215 {
 216   struct passwd *pw;
 217   char *ptr;
 218   char *copy;
 219
 220   if ((ptr = getenv ("HOME")) == NULL)
 221     {
 222       if ((ptr = getenv ("LOGNAME")) != NULL
 223           || (ptr = getenv ("USER")) != NULL)
 224         pw = getpwnam (ptr);
 225       else
 226         pw = getpwuid (getuid ());
 227
 228       if (pw)
 229         ptr = pw->pw_dir;
 230     }
 231
 232   if (ptr == NULL)
 233     return xstrdup ("/");
 234
 235   copy = xmalloc (strlen (ptr) + 2);
 236   strcpy (copy, ptr);
 237   return strcat (copy, "/");
 238 }
 239
 240
 241 /* Find the first element of SEARCH_PATH which exists and is readable,
 242    after expanding the %-escapes.  Return 0 if we didn't find any, and
 243    the path name of the one we found otherwise.  */
 244
 245 static XrmDatabase
 246 search_magic_path (const char *search_path, const char *class,
 247                    const char *escaped_suffix)
 248 {
 249   const char *s, *p;
 250
 251   for (s = search_path; *s; s = p)
 252     {
 253       for (p = s; *p && *p != ':'; p++)
 254         ;
 255
 256       if (p > s)
 257         {
 258           XrmDatabase db = magic_db (s, p - s, class, escaped_suffix);
 259           if (db)
 260             return db;
 261         }
 262       else if (*p == ':')
 263         {
 264           static char const ns[] = "%N%S";
 265           XrmDatabase db = magic_db (ns, strlen (ns), class, escaped_suffix);
 266           if (db)
 267             return db;
 268         }
 269
 270       if (*p == ':')
 271         p++;
 272     }
 273
 274   return 0;
 275 }
 276 \f
 277 /* Producing databases for individual sources.  */
 278
 279 static XrmDatabase
 280 get_system_app (const char *class)
 281 {
 282   const char *path;
 283
 284   path = getenv ("XFILESEARCHPATH");
 285   if (! path) path = PATH_X_DEFAULTS;
 286
 287   return search_magic_path (path, class, 0);
 288 }
 289
 290
 291 static XrmDatabase
 292 get_fallback (Display *display)
 293 {
 294   return NULL;
 295 }
 296
 297
 298 static XrmDatabase
 299 get_user_app (const char *class)
 300 {
 301   XrmDatabase db = 0;
 302   const char *path;
 303
 304   /* Check for XUSERFILESEARCHPATH.  It is a path of complete file
 305      names, not directories.  */
 306   path = getenv ("XUSERFILESEARCHPATH");
 307   if (path)
 308     db = search_magic_path (path, class, 0);
 309
 310   if (! db)
 311     {
 312       /* Check for APPLRESDIR; it is a path of directories.  In each,
 313          we have to search for LANG/CLASS and then CLASS.  */
 314       path = getenv ("XAPPLRESDIR");
 315       if (path)
 316         {
 317           db = search_magic_path (path, class, "/%L/%N");
 318           if (!db)
 319             db = search_magic_path (path, class, "/%N");
 320         }
 321     }
 322
 323   if (! db)
 324     {
 325       /* Check in the home directory.  This is a bit of a hack; let's
 326          hope one's home directory doesn't contain any %-escapes.  */
 327       char *home = gethomedir ();
 328       db = search_magic_path (home, class, "%L/%N");
 329       if (! db)
 330         db = search_magic_path (home, class, "%N");
 331       xfree (home);
 332     }
 333
 334   return db;
 335 }
 336
 337
 338 static XrmDatabase
 339 get_user_db (Display *display)
 340 {
 341   XrmDatabase db;
 342   char *xdefs;
 343
 344 #ifdef PBaseSize                /* Cheap way to test for X11R4 or later.  */
 345   xdefs = XResourceManagerString (display);
 346 #else
 347   xdefs = display->xdefaults;
 348 #endif
 349
 350   if (xdefs != NULL)
 351     db = XrmGetStringDatabase (xdefs);
 352   else
 353     {
 354       char *home;
 355       char *xdefault;
 356
 357       home = gethomedir ();
 358       xdefault = xmalloc (strlen (home) + sizeof ".Xdefaults");
 359       strcpy (xdefault, home);
 360       strcat (xdefault, ".Xdefaults");
 361       db = XrmGetFileDatabase (xdefault);
 362       xfree (home);
 363       xfree (xdefault);
 364     }
 365
 366 #ifdef HAVE_XSCREENRESOURCESTRING
 367   /* Get the screen-specific resources too.  */
 368   xdefs = XScreenResourceString (DefaultScreenOfDisplay (display));
 369   if (xdefs != NULL)
 370     {
 371       XrmMergeDatabases (XrmGetStringDatabase (xdefs), &db);
 372       XFree (xdefs);
 373     }
 374 #endif
 375
 376   return db;
 377 }
 378
 379 static XrmDatabase
 380 get_environ_db (void)
 381 {
 382   XrmDatabase db;
 383   char *p;
 384   char *path = 0;
 385
 386   if ((p = getenv ("XENVIRONMENT")) == NULL)
 387     {
 388       static char const xdefaults[] = ".Xdefaults-";
 389       char *home = gethomedir ();
 390       char const *host = SSDATA (Vsystem_name);
 391       ptrdiff_t pathsize = (strlen (home) + sizeof xdefaults
 392                             + SBYTES (Vsystem_name));
 393       path = xrealloc (home, pathsize);
 394       strcat (strcat (path, xdefaults), host);
 395       p = path;
 396     }
 397
 398   db = XrmGetFileDatabase (p);
 399
 400   xfree (path);
 401
 402   return db;
 403 }
 404 \f
 405 /* External interface.  */
 406
 407 /* Types of values that we can find in a database */
 408
 409 #define XrmStringType "String"  /* String representation */
 410 static XrmRepresentation x_rm_string;   /* Quark representation */
 411
 412 /* Load X resources based on the display and a possible -xrm option. */
 413
 414 XrmDatabase
 415 x_load_resources (Display *display, const char *xrm_string,
 416                   const char *myname, const char *myclass)
 417 {
 418   XrmDatabase user_database;
 419   XrmDatabase rdb;
 420   XrmDatabase db;
 421   char line[256];
 422
 423 #if defined USE_MOTIF || !defined HAVE_XFT || !defined USE_LUCID
 424   const char *helv = "-*-helvetica-medium-r-*--*-120-*-*-*-*-iso8859-1";
 425 #endif
 426
 427 #ifdef USE_MOTIF
 428   const char *courier = "-*-courier-medium-r-*-*-*-120-*-*-*-*-iso8859-1";
 429 #endif
 430
 431   x_rm_string = XrmStringToQuark (XrmStringType);
 432 #ifndef USE_X_TOOLKIT
 433   /* pmr@osf.org says this shouldn't be done if USE_X_TOOLKIT.
 434      I suspect it's because the toolkit version does this elsewhere.  */
 435   XrmInitialize ();
 436 #endif
 437   rdb = XrmGetStringDatabase ("");
 438
 439   /* Add some font defaults.  If the font `helv' doesn't exist, widgets
 440      will use some other default font.  */
 441 #ifdef USE_MOTIF
 442
 443   sprintf (line, "%s.pane.background: grey75", myclass);
 444   XrmPutLineResource (&rdb, line);
 445   sprintf (line, "%s*fontList: %s", myclass, helv);
 446   XrmPutLineResource (&rdb, line);
 447   sprintf (line, "%s*menu*background: grey75", myclass);
 448   XrmPutLineResource (&rdb, line);
 449   sprintf (line, "%s*menubar*background: grey75", myclass);
 450   XrmPutLineResource (&rdb, line);
 451   sprintf (line, "%s*verticalScrollBar.background: grey75", myclass);
 452   XrmPutLineResource (&rdb, line);
 453   sprintf (line, "%s*verticalScrollBar.troughColor: grey75", myclass);
 454   XrmPutLineResource (&rdb, line);
 455   sprintf (line, "%s.dialog*.background: grey75", myclass);
 456   XrmPutLineResource (&rdb, line);
 457   sprintf (line, "%s*fsb.Text.background: white", myclass);
 458   XrmPutLineResource (&rdb, line);
 459   sprintf (line, "%s*fsb.FilterText.background: white", myclass);
 460   XrmPutLineResource (&rdb, line);
 461   sprintf (line, "%s*fsb*DirList.background: white", myclass);
 462   XrmPutLineResource (&rdb, line);
 463   sprintf (line, "%s*fsb*ItemsList.background: white", myclass);
 464   XrmPutLineResource (&rdb, line);
 465   sprintf (line, "%s*fsb*background: grey75", myclass);
 466   XrmPutLineResource (&rdb, line);
 467   sprintf (line, "%s*fsb.Text.fontList: %s", myclass, courier);
 468   XrmPutLineResource (&rdb, line);
 469   sprintf (line, "%s*fsb.FilterText.fontList: %s", myclass, courier);
 470   XrmPutLineResource (&rdb, line);
 471   sprintf (line, "%s*fsb*ItemsList.fontList: %s", myclass, courier);
 472   XrmPutLineResource (&rdb, line);
 473   sprintf (line, "%s*fsb*DirList.fontList: %s", myclass, courier);
 474   XrmPutLineResource (&rdb, line);
 475
 476   /* Set double click time of list boxes in the file selection
 477      dialog from `double-click-time'.  */
 478   if (INTEGERP (Vdouble_click_time) && XINT (Vdouble_click_time) > 0)
 479     {
 480       sprintf (line, "%s*fsb*DirList.doubleClickInterval: %"pI"d",
 481                myclass, XFASTINT (Vdouble_click_time));
 482       XrmPutLineResource (&rdb, line);
 483       sprintf (line, "%s*fsb*ItemsList.doubleClickInterval: %"pI"d",
 484                myclass, XFASTINT (Vdouble_click_time));
 485       XrmPutLineResource (&rdb, line);
 486     }
 487
 488 #else /* not USE_MOTIF */
 489
 490   sprintf (line, "Emacs.dialog*.background: grey75");
 491   XrmPutLineResource (&rdb, line);
 492 #if !defined (HAVE_XFT) || !defined (USE_LUCID)
 493   sprintf (line, "Emacs.dialog*.font: %s", helv);
 494   XrmPutLineResource (&rdb, line);
 495   sprintf (line, "*XlwMenu*font: %s", helv);
 496   XrmPutLineResource (&rdb, line);
 497 #endif
 498   sprintf (line, "*XlwMenu*background: grey75");
 499   XrmPutLineResource (&rdb, line);
 500   sprintf (line, "Emacs*verticalScrollBar.background: grey75");
 501   XrmPutLineResource (&rdb, line);
 502
 503 #endif /* not USE_MOTIF */
 504
 505   user_database = get_user_db (display);
 506
 507   /* Figure out what the "customization string" is, so we can use it
 508      to decode paths.  */
 509   xfree (x_customization_string);
 510   x_customization_string
 511     = x_get_customization_string (user_database, myname, myclass);
 512
 513   /* Get application system defaults */
 514   db = get_system_app (myclass);
 515   if (db != NULL)
 516     XrmMergeDatabases (db, &rdb);
 517
 518   /* Get Fallback resources */
 519   db = get_fallback (display);
 520   if (db != NULL)
 521     XrmMergeDatabases (db, &rdb);
 522
 523   /* Get application user defaults */
 524   db = get_user_app (myclass);
 525   if (db != NULL)
 526     XrmMergeDatabases (db, &rdb);
 527
 528   /* get User defaults */
 529   if (user_database != NULL)
 530     XrmMergeDatabases (user_database, &rdb);
 531
 532   /* Get Environment defaults. */
 533   db = get_environ_db ();
 534   if (db != NULL)
 535     XrmMergeDatabases (db, &rdb);
 536
 537   /* Last, merge in any specification from the command line. */
 538   if (xrm_string != NULL)
 539     {
 540       db = XrmGetStringDatabase (xrm_string);
 541       if (db != NULL)
 542         XrmMergeDatabases (db, &rdb);
 543     }
 544
 545   return rdb;
 546 }
 547
 548
 549 /* Retrieve the value of the resource specified by NAME with class CLASS
 550    and of type TYPE from database RDB.  The value is returned in RET_VALUE. */
 551
 552 static int
 553 x_get_resource (XrmDatabase rdb, const char *name, const char *class,
 554                 XrmRepresentation expected_type, XrmValue *ret_value)
 555 {
 556   XrmValue value;
 557   XrmName namelist[100];
 558   XrmClass classlist[100];
 559   XrmRepresentation type;
 560
 561   XrmStringToNameList (name, namelist);
 562   XrmStringToClassList (class, classlist);
 563
 564   if (XrmQGetResource (rdb, namelist, classlist, &type, &value) == True
 565       && (type == expected_type))
 566     {
 567       if (type == x_rm_string)
 568         ret_value->addr = (char *) value.addr;
 569       else
 570         memcpy (ret_value->addr, value.addr, ret_value->size);
 571
 572       return value.size;
 573     }
 574
 575   return 0;
 576 }
 577
 578 /* Retrieve the string resource specified by NAME with CLASS from
 579    database RDB. */
 580
 581 char *
 582 x_get_string_resource (XrmDatabase rdb, const char *name, const char *class)
 583 {
 584   XrmValue value;
 585
 586   if (inhibit_x_resources)
 587     /* --quick was passed, so this is a no-op.  */
 588     return NULL;
 589
 590   if (x_get_resource (rdb, name, class, x_rm_string, &value))
 591     return (char *) value.addr;
 592
 593   return 0;
 594 }
 595 \f
 596 /* Stand-alone test facilities.  */
 597
 598 #ifdef TESTRM
 599
 600 typedef char **List;
 601 #define arg_listify(len, list) (list)
 602 #define car(list) (*(list))
 603 #define cdr(list) (list + 1)
 604 #define NIL(list) (! *(list))
 605 #define free_arglist(list)
 606
 607 static List
 608 member (char *elt, List list)
 609 {
 610   List p;
 611
 612   for (p = list; ! NIL (p); p = cdr (p))
 613     if (! strcmp (elt, car (p)))
 614       return p;
 615
 616   return p;
 617 }
 618
 619 static void
 620 fatal (char *msg, char *prog)
 621 {
 622   fprintf (stderr, msg, prog);
 623   exit (1);
 624 }
 625
 626 int
 627 main (int argc, char **argv)
 628 {
 629   Display *display;
 630   char *displayname, *resource_string, *class, *name;
 631   XrmDatabase xdb;
 632   List arg_list, lp;
 633
 634   arg_list = arg_listify (argc, argv);
 635
 636   lp = member ("-d", arg_list);
 637   if (!NIL (lp))
 638     displayname = car (cdr (lp));
 639   else
 640     displayname = "localhost:0.0";
 641
 642   lp = member ("-xrm", arg_list);
 643   resource_string = NIL (lp) ? 0 : car (cdr (lp));
 644
 645   lp = member ("-c", arg_list);
 646   if (! NIL (lp))
 647     class = car (cdr (lp));
 648   else
 649     class = "Emacs";
 650
 651   lp = member ("-n", arg_list);
 652   if (! NIL (lp))
 653     name = car (cdr (lp));
 654   else
 655     name = "emacs";
 656
 657   free_arglist (arg_list);
 658
 659   if (!(display = XOpenDisplay (displayname)))
 660     fatal ("Can't open display '%s'\n", XDisplayName (displayname));
 661
 662   xdb = x_load_resources (display, resource_string, name, class);
 663
 664   /* In a real program, you'd want to also do this: */
 665   display->db = xdb;
 666
 667   while (1)
 668     {
 669       char query_name[90];
 670       char query_class[90];
 671
 672       printf ("Name: ");
 673       gets (query_name);
 674
 675       if (strlen (query_name))
 676         {
 677           char *value;
 678
 679           printf ("Class: ");
 680           gets (query_class);
 681
 682           value = x_get_string_resource (xdb, query_name, query_class);
 683
 684           if (value != NULL)
 685             printf ("\t%s(%s):  %s\n\n", query_name, query_class, value);
 686           else
 687             printf ("\tNo Value.\n\n");
 688         }
 689       else
 690         break;
 691     }
 692   printf ("\tExit.\n\n");
 693
 694   XCloseDisplay (display);
 695
 696   return 0;
 697 }
 698 #endif /* TESTRM */