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