src/xrdb.c

   1 /* Deal with the X Resource Manager.
   2    Copyright (C) 1990, 1993, 1994, 2000, 2001, 2002, 2003, 2004,
   3                  2005, 2006, 2007, 2008, 2009, 2010 Free Software Foundation, 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 #ifdef HAVE_UNISTD_H
  26 #include <unistd.h>
  27 #endif
  28
  29 #include <errno.h>
  30 #include <epaths.h>
  31
  32 #include <stdio.h>
  33 #include <setjmp.h>
  34
  35 #include <X11/Xlib.h>
  36 #include <X11/Xatom.h>
  37 #include <X11/X.h>
  38 #include <X11/Xutil.h>
  39 #include <X11/Xresource.h>
  40 #ifdef HAVE_PWD_H
  41 #include <pwd.h>
  42 #endif
  43 #include <sys/stat.h>
  44
  45 #if !defined(S_ISDIR) && defined(S_IFDIR)
  46 #define S_ISDIR(m) (((m) & S_IFMT) == S_IFDIR)
  47 #endif
  48
  49 #include "lisp.h"
  50
  51 extern char *getenv (const char *);
  52
  53 extern struct passwd *getpwuid (uid_t);
  54 extern struct passwd *getpwnam (const char *);
  55
  56 extern const char *get_system_name (void);
  57
  58 char *x_get_string_resource (XrmDatabase rdb, const char *name,
  59                              const char *class);
  60 static int file_p (const char *filename);
  61
  62 \f
  63 /* X file search path processing.  */
  64
  65
  66 /* The string which gets substituted for the %C escape in XFILESEARCHPATH
  67    and friends, or zero if none was specified.  */
  68 char *x_customization_string;
  69
  70
  71 /* Return the value of the emacs.customization (Emacs.Customization)
  72    resource, for later use in search path decoding.  If we find no
  73    such resource, return zero.  */
  74 char *
  75 x_get_customization_string (XrmDatabase db, const char *name, const char *class)
  76 {
  77   char *full_name
  78     = (char *) alloca (strlen (name) + sizeof ("customization") + 3);
  79   char *full_class
  80     = (char *) alloca (strlen (class) + sizeof ("Customization") + 3);
  81   char *result;
  82
  83   sprintf (full_name,  "%s.%s", name,  "customization");
  84   sprintf (full_class, "%s.%s", class, "Customization");
  85
  86   result = x_get_string_resource (db, full_name, full_class);
  87
  88   if (result)
  89     {
  90       char *copy = (char *) xmalloc (strlen (result) + 1);
  91       strcpy (copy, result);
  92       return copy;
  93     }
  94   else
  95     return 0;
  96 }
  97
  98
  99 /* Expand all the Xt-style %-escapes in STRING, whose length is given
 100    by STRING_LEN.  Here are the escapes we're supposed to recognize:
 101
 102         %N      The value of the application's class name
 103         %T      The value of the type parameter ("app-defaults" in this
 104                 context)
 105         %S      The value of the suffix parameter ("" in this context)
 106         %L      The language string associated with the specified display
 107                 (We use the "LANG" environment variable here, if it's set.)
 108         %l      The language part of the display's language string
 109                 (We treat this just like %L.  If someone can tell us what
 110                  we're really supposed to do, dandy.)
 111         %t      The territory part of the display's language string
 112                 (This never gets used.)
 113         %c      The codeset part of the display's language string
 114                 (This never gets used either.)
 115         %C      The customization string retrieved from the resource
 116                 database associated with display.
 117                 (This is x_customization_string.)
 118
 119    Return the expanded file name if it exists and is readable, and
 120    refers to %L only when the LANG environment variable is set, or
 121    otherwise provided by X.
 122
 123    ESCAPED_SUFFIX and SUFFIX are postpended to STRING if they are
 124    non-zero.  %-escapes in ESCAPED_SUFFIX are expanded; STRING is left
 125    alone.
 126
 127    Return NULL otherwise.  */
 128
 129 static char *
 130 magic_file_p (const char *string, EMACS_INT string_len, const char *class, const char *escaped_suffix, const char *suffix)
 131 {
 132   char *lang = getenv ("LANG");
 133
 134   int path_size = 100;
 135   char *path = (char *) xmalloc (path_size);
 136   int path_len = 0;
 137
 138   const char *p = string;
 139
 140   while (p < string + string_len)
 141     {
 142       /* The chunk we're about to stick on the end of result.  */
 143       const char *next = NULL;
 144       int next_len;
 145
 146       if (*p == '%')
 147         {
 148           p++;
 149
 150           if (p >= string + string_len)
 151             next_len = 0;
 152           else
 153             switch (*p)
 154               {
 155               case '%':
 156                 next = "%";
 157                 next_len = 1;
 158                 break;
 159
 160               case 'C':
 161                 next = (x_customization_string
 162                         ? x_customization_string
 163                         : "");
 164                 next_len = strlen (next);
 165                 break;
 166
 167               case 'N':
 168                 next = class;
 169                 next_len = strlen (class);
 170                 break;
 171
 172               case 'T':
 173                 next = "app-defaults";
 174                 next_len = strlen (next);
 175                 break;
 176
 177               default:
 178               case 'S':
 179                 next_len = 0;
 180                 break;
 181
 182               case 'L':
 183               case 'l':
 184                 if (! lang)
 185                   {
 186                     xfree (path);
 187                     return NULL;
 188                   }
 189
 190                 next = lang;
 191                 next_len = strlen (next);
 192                 break;
 193
 194               case 't':
 195               case 'c':
 196                 xfree (path);
 197                 return NULL;
 198               }
 199         }
 200       else
 201         next = p, next_len = 1;
 202
 203       /* Do we have room for this component followed by a '\0' ?  */
 204       if (path_len + next_len + 1 > path_size)
 205         {
 206           path_size = (path_len + next_len + 1) * 2;
 207           path = (char *) xrealloc (path, path_size);
 208         }
 209
 210       memcpy (path + path_len, next, next_len);
 211       path_len += next_len;
 212
 213       p++;
 214
 215       /* If we've reached the end of the string, append ESCAPED_SUFFIX.  */
 216       if (p >= string + string_len && escaped_suffix)
 217         {
 218           string = escaped_suffix;
 219           string_len = strlen (string);
 220           p = string;
 221           escaped_suffix = NULL;
 222         }
 223     }
 224
 225   /* Perhaps we should add the SUFFIX now.  */
 226   if (suffix)
 227     {
 228       int suffix_len = strlen (suffix);
 229
 230       if (path_len + suffix_len + 1 > path_size)
 231         {
 232           path_size = (path_len + suffix_len + 1);
 233           path = (char *) xrealloc (path, path_size);
 234         }
 235
 236       memcpy (path + path_len, suffix, suffix_len);
 237       path_len += suffix_len;
 238     }
 239
 240   path[path_len] = '\0';
 241
 242   if (! file_p (path))
 243     {
 244       xfree (path);
 245       return NULL;
 246     }
 247
 248   return path;
 249 }
 250
 251
 252 static char *
 253 gethomedir (void)
 254 {
 255   struct passwd *pw;
 256   char *ptr;
 257   char *copy;
 258
 259   if ((ptr = getenv ("HOME")) == NULL)
 260     {
 261       if ((ptr = getenv ("LOGNAME")) != NULL
 262           || (ptr = getenv ("USER")) != NULL)
 263         pw = getpwnam (ptr);
 264       else
 265         pw = getpwuid (getuid ());
 266
 267       if (pw)
 268         ptr = pw->pw_dir;
 269     }
 270
 271   if (ptr == NULL)
 272     return xstrdup ("/");
 273
 274   copy = (char *) xmalloc (strlen (ptr) + 2);
 275   strcpy (copy, ptr);
 276   strcat (copy, "/");
 277
 278   return copy;
 279 }
 280
 281
 282 static int
 283 file_p (const char *filename)
 284 {
 285   struct stat status;
 286
 287   return (access (filename, 4) == 0             /* exists and is readable */
 288           && stat (filename, &status) == 0      /* get the status */
 289           && (S_ISDIR (status.st_mode)) == 0);  /* not a directory */
 290 }
 291
 292
 293 /* Find the first element of SEARCH_PATH which exists and is readable,
 294    after expanding the %-escapes.  Return 0 if we didn't find any, and
 295    the path name of the one we found otherwise.  */
 296
 297 static char *
 298 search_magic_path (const char *search_path, const char *class, const char *escaped_suffix, const char *suffix)
 299 {
 300   const char *s, *p;
 301
 302   for (s = search_path; *s; s = p)
 303     {
 304       for (p = s; *p && *p != ':'; p++)
 305         ;
 306
 307       if (p > s)
 308         {
 309           char *path = magic_file_p (s, p - s, class, escaped_suffix,
 310                                            suffix);
 311           if (path)
 312             return path;
 313         }
 314       else if (*p == ':')
 315         {
 316           char *path;
 317
 318           s = "%N%S";
 319           path = magic_file_p (s, strlen (s), class, escaped_suffix, suffix);
 320           if (path)
 321             return path;
 322         }
 323
 324       if (*p == ':')
 325         p++;
 326     }
 327
 328   return 0;
 329 }
 330 \f
 331 /* Producing databases for individual sources.  */
 332
 333 static XrmDatabase
 334 get_system_app (const char *class)
 335 {
 336   XrmDatabase db = NULL;
 337   const char *path;
 338   char *p;
 339
 340   path = getenv ("XFILESEARCHPATH");
 341   if (! path) path = PATH_X_DEFAULTS;
 342
 343   p = search_magic_path (path, class, 0, 0);
 344   if (p)
 345     {
 346       db = XrmGetFileDatabase (p);
 347       xfree (p);
 348     }
 349
 350   return db;
 351 }
 352
 353
 354 static XrmDatabase
 355 get_fallback (Display *display)
 356 {
 357   return NULL;
 358 }
 359
 360
 361 static XrmDatabase
 362 get_user_app (const char *class)
 363 {
 364   const char *path;
 365   char *file = 0;
 366   char *free_it = 0;
 367
 368   /* Check for XUSERFILESEARCHPATH.  It is a path of complete file
 369      names, not directories.  */
 370   if (((path = getenv ("XUSERFILESEARCHPATH"))
 371        && (file = search_magic_path (path, class, 0, 0)))
 372
 373       /* Check for APPLRESDIR; it is a path of directories.  In each,
 374          we have to search for LANG/CLASS and then CLASS.  */
 375       || ((path = getenv ("XAPPLRESDIR"))
 376           && ((file = search_magic_path (path, class, "/%L/%N", 0))
 377               || (file = search_magic_path (path, class, "/%N", 0))))
 378
 379       /* Check in the home directory.  This is a bit of a hack; let's
 380          hope one's home directory doesn't contain any %-escapes.  */
 381       || (free_it = gethomedir (),
 382           ((file = search_magic_path (free_it, class, "%L/%N", 0))
 383            || (file = search_magic_path (free_it, class, "%N", 0)))))
 384     {
 385       XrmDatabase db = XrmGetFileDatabase (file);
 386       xfree (file);
 387       xfree (free_it);
 388       return db;
 389     }
 390
 391   xfree (free_it);
 392   return NULL;
 393 }
 394
 395
 396 static XrmDatabase
 397 get_user_db (Display *display)
 398 {
 399   XrmDatabase db;
 400   char *xdefs;
 401
 402 #ifdef PBaseSize                /* Cheap way to test for X11R4 or later.  */
 403   xdefs = XResourceManagerString (display);
 404 #else
 405   xdefs = display->xdefaults;
 406 #endif
 407
 408   if (xdefs != NULL)
 409     db = XrmGetStringDatabase (xdefs);
 410   else
 411     {
 412       char *home;
 413       char *xdefault;
 414
 415       home = gethomedir ();
 416       xdefault = (char *) xmalloc (strlen (home) + sizeof (".Xdefaults"));
 417       strcpy (xdefault, home);
 418       strcat (xdefault, ".Xdefaults");
 419       db = XrmGetFileDatabase (xdefault);
 420       xfree (home);
 421       xfree (xdefault);
 422     }
 423
 424 #ifdef HAVE_XSCREENRESOURCESTRING
 425   /* Get the screen-specific resources too.  */
 426   xdefs = XScreenResourceString (DefaultScreenOfDisplay (display));
 427   if (xdefs != NULL)
 428     {
 429       XrmMergeDatabases (XrmGetStringDatabase (xdefs), &db);
 430       XFree (xdefs);
 431     }
 432 #endif
 433
 434   return db;
 435 }
 436
 437 static XrmDatabase
 438 get_environ_db (void)
 439 {
 440   XrmDatabase db;
 441   char *p;
 442   char *path = 0, *home = 0;
 443   const char *host;
 444
 445   if ((p = getenv ("XENVIRONMENT")) == NULL)
 446     {
 447       home = gethomedir ();
 448       host = get_system_name ();
 449       path = (char *) xmalloc (strlen (home)
 450                               + sizeof (".Xdefaults-")
 451                               + strlen (host));
 452       sprintf (path, "%s%s%s", home, ".Xdefaults-", host);
 453       p = path;
 454     }
 455
 456   db = XrmGetFileDatabase (p);
 457
 458   xfree (path);
 459   xfree (home);
 460
 461   return db;
 462 }
 463 \f
 464 /* External interface.  */
 465
 466 /* Types of values that we can find in a database */
 467
 468 #define XrmStringType "String"  /* String representation */
 469 XrmRepresentation x_rm_string;  /* Quark representation */
 470
 471 /* Load X resources based on the display and a possible -xrm option. */
 472
 473 XrmDatabase
 474 x_load_resources (Display *display, const char *xrm_string,
 475                   const char *myname, const char *myclass)
 476 {
 477   XrmDatabase user_database;
 478   XrmDatabase rdb;
 479   XrmDatabase db;
 480   char line[256];
 481
 482   const char *helv = "-*-helvetica-medium-r-*--*-120-*-*-*-*-iso8859-1";
 483
 484 #ifdef USE_MOTIF
 485   const char *courier = "-*-courier-medium-r-*-*-*-120-*-*-*-*-iso8859-1";
 486 #endif
 487
 488   x_rm_string = XrmStringToQuark (XrmStringType);
 489 #ifndef USE_X_TOOLKIT
 490   /* pmr@osf.org says this shouldn't be done if USE_X_TOOLKIT.
 491      I suspect it's because the toolkit version does this elsewhere.  */
 492   XrmInitialize ();
 493 #endif
 494   rdb = XrmGetStringDatabase ("");
 495
 496   /* Add some font defaults.  If the font `helv' doesn't exist, widgets
 497      will use some other default font.  */
 498 #ifdef USE_MOTIF
 499
 500   sprintf (line, "%s.pane.background: grey75", myclass);
 501   XrmPutLineResource (&rdb, line);
 502   sprintf (line, "%s*fontList: %s", myclass, helv);
 503   XrmPutLineResource (&rdb, line);
 504   sprintf (line, "%s*menu*background: grey75", myclass);
 505   XrmPutLineResource (&rdb, line);
 506   sprintf (line, "%s*menubar*background: grey75", myclass);
 507   XrmPutLineResource (&rdb, line);
 508   sprintf (line, "%s*verticalScrollBar.background: grey75", myclass);
 509   XrmPutLineResource (&rdb, line);
 510   sprintf (line, "%s*verticalScrollBar.troughColor: grey75", myclass);
 511   XrmPutLineResource (&rdb, line);
 512   sprintf (line, "%s.dialog*.background: grey75", myclass);
 513   XrmPutLineResource (&rdb, line);
 514   sprintf (line, "%s*fsb.Text.background: white", myclass);
 515   XrmPutLineResource (&rdb, line);
 516   sprintf (line, "%s*fsb.FilterText.background: white", myclass);
 517   XrmPutLineResource (&rdb, line);
 518   sprintf (line, "%s*fsb*DirList.background: white", myclass);
 519   XrmPutLineResource (&rdb, line);
 520   sprintf (line, "%s*fsb*ItemsList.background: white", myclass);
 521   XrmPutLineResource (&rdb, line);
 522   sprintf (line, "%s*fsb*background: grey75", myclass);
 523   XrmPutLineResource (&rdb, line);
 524   sprintf (line, "%s*fsb.Text.fontList: %s", myclass, courier);
 525   XrmPutLineResource (&rdb, line);
 526   sprintf (line, "%s*fsb.FilterText.fontList: %s", myclass, courier);
 527   XrmPutLineResource (&rdb, line);
 528   sprintf (line, "%s*fsb*ItemsList.fontList: %s", myclass, courier);
 529   XrmPutLineResource (&rdb, line);
 530   sprintf (line, "%s*fsb*DirList.fontList: %s", myclass, courier);
 531   XrmPutLineResource (&rdb, line);
 532
 533   /* Set double click time of list boxes in the file selection
 534      dialog from `double-click-time'.  */
 535   if (INTEGERP (Vdouble_click_time) && XINT (Vdouble_click_time) > 0)
 536     {
 537       sprintf (line, "%s*fsb*DirList.doubleClickInterval: %d",
 538                myclass, XFASTINT (Vdouble_click_time));
 539       XrmPutLineResource (&rdb, line);
 540       sprintf (line, "%s*fsb*ItemsList.doubleClickInterval: %d",
 541                myclass, XFASTINT (Vdouble_click_time));
 542       XrmPutLineResource (&rdb, line);
 543     }
 544
 545 #else /* not USE_MOTIF */
 546
 547   sprintf (line, "Emacs.dialog*.font: %s", helv);
 548   XrmPutLineResource (&rdb, line);
 549   sprintf (line, "Emacs.dialog*.background: grey75");
 550   XrmPutLineResource (&rdb, line);
 551   sprintf (line, "*XlwMenu*font: %s", helv);
 552   XrmPutLineResource (&rdb, line);
 553   sprintf (line, "*XlwMenu*background: grey75");
 554   XrmPutLineResource (&rdb, line);
 555   sprintf (line, "Emacs*verticalScrollBar.background: grey75");
 556   XrmPutLineResource (&rdb, line);
 557
 558 #endif /* not USE_MOTIF */
 559
 560   user_database = get_user_db (display);
 561
 562   /* Figure out what the "customization string" is, so we can use it
 563      to decode paths.  */
 564   xfree (x_customization_string);
 565   x_customization_string
 566     = x_get_customization_string (user_database, myname, myclass);
 567
 568   /* Get application system defaults */
 569   db = get_system_app (myclass);
 570   if (db != NULL)
 571     XrmMergeDatabases (db, &rdb);
 572
 573   /* Get Fallback resources */
 574   db = get_fallback (display);
 575   if (db != NULL)
 576     XrmMergeDatabases (db, &rdb);
 577
 578   /* Get application user defaults */
 579   db = get_user_app (myclass);
 580   if (db != NULL)
 581     XrmMergeDatabases (db, &rdb);
 582
 583   /* get User defaults */
 584   if (user_database != NULL)
 585     XrmMergeDatabases (user_database, &rdb);
 586
 587   /* Get Environment defaults. */
 588   db = get_environ_db ();
 589   if (db != NULL)
 590     XrmMergeDatabases (db, &rdb);
 591
 592   /* Last, merge in any specification from the command line. */
 593   if (xrm_string != NULL)
 594     {
 595       db = XrmGetStringDatabase (xrm_string);
 596       if (db != NULL)
 597         XrmMergeDatabases (db, &rdb);
 598     }
 599
 600   return rdb;
 601 }
 602
 603
 604 /* Retrieve the value of the resource specified by NAME with class CLASS
 605    and of type TYPE from database RDB.  The value is returned in RET_VALUE. */
 606
 607 int
 608 x_get_resource (XrmDatabase rdb, const char *name, const char *class, XrmRepresentation expected_type, XrmValue *ret_value)
 609 {
 610   XrmValue value;
 611   XrmName namelist[100];
 612   XrmClass classlist[100];
 613   XrmRepresentation type;
 614
 615   XrmStringToNameList(name, namelist);
 616   XrmStringToClassList(class, classlist);
 617
 618   if (XrmQGetResource (rdb, namelist, classlist, &type, &value) == True
 619       && (type == expected_type))
 620     {
 621       if (type == x_rm_string)
 622         ret_value->addr = (char *) value.addr;
 623       else
 624         memcpy (ret_value->addr, value.addr, ret_value->size);
 625
 626       return value.size;
 627     }
 628
 629   return 0;
 630 }
 631
 632 /* Retrieve the string resource specified by NAME with CLASS from
 633    database RDB. */
 634
 635 char *
 636 x_get_string_resource (XrmDatabase rdb, const char *name, const char *class)
 637 {
 638   XrmValue value;
 639
 640   if (inhibit_x_resources)
 641     /* --quick was passed, so this is a no-op.  */
 642     return NULL;
 643
 644   if (x_get_resource (rdb, name, class, x_rm_string, &value))
 645     return (char *) value.addr;
 646
 647   return (char *) 0;
 648 }
 649 \f
 650 /* Stand-alone test facilities.  */
 651
 652 #ifdef TESTRM
 653
 654 typedef char **List;
 655 #define arg_listify(len, list) (list)
 656 #define car(list) (*(list))
 657 #define cdr(list) (list + 1)
 658 #define NIL(list) (! *(list))
 659 #define free_arglist(list)
 660
 661 static List
 662 member (elt, list)
 663      char *elt;
 664      List list;
 665 {
 666   List p;
 667
 668   for (p = list; ! NIL (p); p = cdr (p))
 669     if (! strcmp (elt, car (p)))
 670       return p;
 671
 672   return p;
 673 }
 674
 675 static void
 676 fatal (msg, prog, x1, x2, x3, x4, x5)
 677     char *msg, *prog;
 678     int x1, x2, x3, x4, x5;
 679 {
 680     if (errno)
 681       perror (prog);
 682
 683     (void) fprintf (stderr, msg, prog, x1, x2, x3, x4, x5);
 684     exit (1);
 685 }
 686
 687 main (argc, argv)
 688     int argc;
 689     char **argv;
 690 {
 691   Display *display;
 692   char *displayname, *resource_string, *class, *name;
 693   XrmDatabase xdb;
 694   List arg_list, lp;
 695
 696   arg_list = arg_listify (argc, argv);
 697
 698   lp = member ("-d", arg_list);
 699   if (!NIL (lp))
 700     displayname = car (cdr (lp));
 701   else
 702     displayname = "localhost:0.0";
 703
 704   lp = member ("-xrm", arg_list);
 705   if (! NIL (lp))
 706     resource_string = car (cdr (lp));
 707   else
 708     resource_string = (char *) 0;
 709
 710   lp = member ("-c", arg_list);
 711   if (! NIL (lp))
 712     class = car (cdr (lp));
 713   else
 714     class = "Emacs";
 715
 716   lp = member ("-n", arg_list);
 717   if (! NIL (lp))
 718     name = car (cdr (lp));
 719   else
 720     name = "emacs";
 721
 722   free_arglist (arg_list);
 723
 724   if (!(display = XOpenDisplay (displayname)))
 725     fatal ("Can't open display '%s'\n", XDisplayName (displayname));
 726
 727   xdb = x_load_resources (display, resource_string, name, class);
 728
 729   /* In a real program, you'd want to also do this: */
 730   display->db = xdb;
 731
 732   while (1)
 733     {
 734       char query_name[90];
 735       char query_class[90];
 736
 737       printf ("Name: ");
 738       gets (query_name);
 739
 740       if (strlen (query_name))
 741         {
 742           char *value;
 743
 744           printf ("Class: ");
 745           gets (query_class);
 746
 747           value = x_get_string_resource (xdb, query_name, query_class);
 748
 749           if (value != NULL)
 750             printf ("\t%s(%s):  %s\n\n", query_name, query_class, value);
 751           else
 752             printf ("\tNo Value.\n\n");
 753         }
 754       else
 755         break;
 756     }
 757   printf ("\tExit.\n\n");
 758
 759   XCloseDisplay (display);
 760 }
 761 #endif /* TESTRM */
 762
 763 /* arch-tag: 37e6fbab-ed05-4363-9e76-6c4109ed511f
 764    (do not change this comment) */