src/xrdb.c

   1 /* Deal with the X Resource Manager.
   2    Copyright (C) 1990, 1993-1994, 2000-2011 Free Software Foundation, Inc.
   3
   4 Author: Joseph Arceneaux
   5 Created: 4/90
   6
   7 This file is part of GNU Emacs.
   8
   9 GNU Emacs is free software: you can redistribute it and/or modify
  10 it under the terms of the GNU General Public License as published by
  11 the Free Software Foundation, either version 3 of the License, or
  12 (at your option) any later version.
  13
  14 GNU Emacs is distributed in the hope that it will be useful,
  15 but WITHOUT ANY WARRANTY; without even the implied warranty of
  16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17 GNU General Public License for more details.
  18
  19 You should have received a copy of the GNU General Public License
  20 along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
  21
  22 #include <config.h>
  23
  24 #include <unistd.h>
  25 #include <errno.h>
  26 #include <epaths.h>
  27
  28 #include <stdio.h>
  29 #include <setjmp.h>
  30
  31 #include <X11/Xlib.h>
  32 #include <X11/Xatom.h>
  33 #include <X11/X.h>
  34 #include <X11/Xutil.h>
  35 #include <X11/Xresource.h>
  36 #ifdef HAVE_PWD_H
  37 #include <pwd.h>
  38 #endif
  39 #include <sys/stat.h>
  40
  41 #if !defined(S_ISDIR) && defined(S_IFDIR)
  42 #define S_ISDIR(m) (((m) & S_IFMT) == S_IFDIR)
  43 #endif
  44
  45 #include "lisp.h"
  46
  47 #ifdef USE_MOTIF
  48 /* For Vdouble_click_time.  */
  49 #include "keyboard.h"
  50 #endif
  51
  52 extern char *getenv (const char *);
  53
  54 extern struct passwd *getpwuid (uid_t);
  55 extern struct passwd *getpwnam (const char *);
  56
  57 extern const char *get_system_name (void);
  58
  59 char *x_get_string_resource (XrmDatabase rdb, const char *name,
  60                              const char *class);
  61 static int file_p (const char *filename);
  62
  63 \f
  64 /* X file search path processing.  */
  65
  66
  67 /* The string which gets substituted for the %C escape in XFILESEARCHPATH
  68    and friends, or zero if none was specified.  */
  69 char *x_customization_string;
  70
  71
  72 /* Return the value of the emacs.customization (Emacs.Customization)
  73    resource, for later use in search path decoding.  If we find no
  74    such resource, return zero.  */
  75 static char *
  76 x_get_customization_string (XrmDatabase db, const char *name,
  77                             const char *class)
  78 {
  79   char *full_name
  80     = (char *) alloca (strlen (name) + sizeof ("customization") + 3);
  81   char *full_class
  82     = (char *) alloca (strlen (class) + sizeof ("Customization") + 3);
  83   char *result;
  84
  85   sprintf (full_name,  "%s.%s", name,  "customization");
  86   sprintf (full_class, "%s.%s", class, "Customization");
  87
  88   result = x_get_string_resource (db, full_name, full_class);
  89
  90   if (result)
  91     {
  92       char *copy = (char *) xmalloc (strlen (result) + 1);
  93       strcpy (copy, result);
  94       return copy;
  95     }
  96   else
  97     return 0;
  98 }
  99
 100
 101 /* Expand all the Xt-style %-escapes in STRING, whose length is given
 102    by STRING_LEN.  Here are the escapes we're supposed to recognize:
 103
 104         %N      The value of the application's class name
 105         %T      The value of the type parameter ("app-defaults" in this
 106                 context)
 107         %S      The value of the suffix parameter ("" in this context)
 108         %L      The language string associated with the specified display
 109                 (We use the "LANG" environment variable here, if it's set.)
 110         %l      The language part of the display's language string
 111                 (We treat this just like %L.  If someone can tell us what
 112                  we're really supposed to do, dandy.)
 113         %t      The territory part of the display's language string
 114                 (This never gets used.)
 115         %c      The codeset part of the display's language string
 116                 (This never gets used either.)
 117         %C      The customization string retrieved from the resource
 118                 database associated with display.
 119                 (This is x_customization_string.)
 120
 121    Return the expanded file name if it exists and is readable, and
 122    refers to %L only when the LANG environment variable is set, or
 123    otherwise provided by X.
 124
 125    ESCAPED_SUFFIX and SUFFIX are postpended to STRING if they are
 126    non-zero.  %-escapes in ESCAPED_SUFFIX are expanded; STRING is left
 127    alone.
 128
 129    Return NULL otherwise.  */
 130
 131 static char *
 132 magic_file_p (const char *string, EMACS_INT string_len, const char *class, const char *escaped_suffix, const char *suffix)
 133 {
 134   char *lang = getenv ("LANG");
 135
 136   int path_size = 100;
 137   char *path = (char *) xmalloc (path_size);
 138   int path_len = 0;
 139
 140   const char *p = string;
 141
 142   while (p < string + string_len)
 143     {
 144       /* The chunk we're about to stick on the end of result.  */
 145       const char *next = NULL;
 146       int next_len;
 147
 148       if (*p == '%')
 149         {
 150           p++;
 151
 152           if (p >= string + string_len)
 153             next_len = 0;
 154           else
 155             switch (*p)
 156               {
 157               case '%':
 158                 next = "%";
 159                 next_len = 1;
 160                 break;
 161
 162               case 'C':
 163                 next = (x_customization_string
 164                         ? x_customization_string
 165                         : "");
 166                 next_len = strlen (next);
 167                 break;
 168
 169               case 'N':
 170                 next = class;
 171                 next_len = strlen (class);
 172                 break;
 173
 174               case 'T':
 175                 next = "app-defaults";
 176                 next_len = strlen (next);
 177                 break;
 178
 179               default:
 180               case 'S':
 181                 next_len = 0;
 182                 break;
 183
 184               case 'L':
 185               case 'l':
 186                 if (! lang)
 187                   {
 188                     xfree (path);
 189                     return NULL;
 190                   }
 191
 192                 next = lang;
 193                 next_len = strlen (next);
 194                 break;
 195
 196               case 't':
 197               case 'c':
 198                 xfree (path);
 199                 return NULL;
 200               }
 201         }
 202       else
 203         next = p, next_len = 1;
 204
 205       /* Do we have room for this component followed by a '\0' ?  */
 206       if (path_len + next_len + 1 > path_size)
 207         {
 208           path_size = (path_len + next_len + 1) * 2;
 209           path = (char *) xrealloc (path, path_size);
 210         }
 211
 212       memcpy (path + path_len, next, next_len);
 213       path_len += next_len;
 214
 215       p++;
 216
 217       /* If we've reached the end of the string, append ESCAPED_SUFFIX.  */
 218       if (p >= string + string_len && escaped_suffix)
 219         {
 220           string = escaped_suffix;
 221           string_len = strlen (string);
 222           p = string;
 223           escaped_suffix = NULL;
 224         }
 225     }
 226
 227   /* Perhaps we should add the SUFFIX now.  */
 228   if (suffix)
 229     {
 230       int suffix_len = strlen (suffix);
 231
 232       if (path_len + suffix_len + 1 > path_size)
 233         {
 234           path_size = (path_len + suffix_len + 1);
 235           path = (char *) xrealloc (path, path_size);
 236         }
 237
 238       memcpy (path + path_len, suffix, suffix_len);
 239       path_len += suffix_len;
 240     }
 241
 242   path[path_len] = '\0';
 243
 244   if (! file_p (path))
 245     {
 246       xfree (path);
 247       return NULL;
 248     }
 249
 250   return path;
 251 }
 252
 253
 254 static char *
 255 gethomedir (void)
 256 {
 257   struct passwd *pw;
 258   char *ptr;
 259   char *copy;
 260
 261   if ((ptr = getenv ("HOME")) == NULL)
 262     {
 263       if ((ptr = getenv ("LOGNAME")) != NULL
 264           || (ptr = getenv ("USER")) != NULL)
 265         pw = getpwnam (ptr);
 266       else
 267         pw = getpwuid (getuid ());
 268
 269       if (pw)
 270         ptr = pw->pw_dir;
 271     }
 272
 273   if (ptr == NULL)
 274     return xstrdup ("/");
 275
 276   copy = (char *) xmalloc (strlen (ptr) + 2);
 277   strcpy (copy, ptr);
 278   strcat (copy, "/");
 279
 280   return copy;
 281 }
 282
 283
 284 static int
 285 file_p (const char *filename)
 286 {
 287   struct stat status;
 288
 289   return (access (filename, 4) == 0             /* exists and is readable */
 290           && stat (filename, &status) == 0      /* get the status */
 291           && (S_ISDIR (status.st_mode)) == 0);  /* not a directory */
 292 }
 293
 294
 295 /* Find the first element of SEARCH_PATH which exists and is readable,
 296    after expanding the %-escapes.  Return 0 if we didn't find any, and
 297    the path name of the one we found otherwise.  */
 298
 299 static char *
 300 search_magic_path (const char *search_path, const char *class, const char *escaped_suffix, const char *suffix)
 301 {
 302   const char *s, *p;
 303
 304   for (s = search_path; *s; s = p)
 305     {
 306       for (p = s; *p && *p != ':'; p++)
 307         ;
 308
 309       if (p > s)
 310         {
 311           char *path = magic_file_p (s, p - s, class, escaped_suffix,
 312                                            suffix);
 313           if (path)
 314             return path;
 315         }
 316       else if (*p == ':')
 317         {
 318           char *path;
 319
 320           s = "%N%S";
 321           path = magic_file_p (s, strlen (s), class, escaped_suffix, suffix);
 322           if (path)
 323             return path;
 324         }
 325
 326       if (*p == ':')
 327         p++;
 328     }
 329
 330   return 0;
 331 }
 332 \f
 333 /* Producing databases for individual sources.  */
 334
 335 static XrmDatabase
 336 get_system_app (const char *class)
 337 {
 338   XrmDatabase db = NULL;
 339   const char *path;
 340   char *p;
 341
 342   path = getenv ("XFILESEARCHPATH");
 343   if (! path) path = PATH_X_DEFAULTS;
 344
 345   p = search_magic_path (path, class, 0, 0);
 346   if (p)
 347     {
 348       db = XrmGetFileDatabase (p);
 349       xfree (p);
 350     }
 351
 352   return db;
 353 }
 354
 355
 356 static XrmDatabase
 357 get_fallback (Display *display)
 358 {
 359   return NULL;
 360 }
 361
 362
 363 static XrmDatabase
 364 get_user_app (const char *class)
 365 {
 366   const char *path;
 367   char *file = 0;
 368   char *free_it = 0;
 369
 370   /* Check for XUSERFILESEARCHPATH.  It is a path of complete file
 371      names, not directories.  */
 372   if (((path = getenv ("XUSERFILESEARCHPATH"))
 373        && (file = search_magic_path (path, class, 0, 0)))
 374
 375       /* Check for APPLRESDIR; it is a path of directories.  In each,
 376          we have to search for LANG/CLASS and then CLASS.  */
 377       || ((path = getenv ("XAPPLRESDIR"))
 378           && ((file = search_magic_path (path, class, "/%L/%N", 0))
 379               || (file = search_magic_path (path, class, "/%N", 0))))
 380
 381       /* Check in the home directory.  This is a bit of a hack; let's
 382          hope one's home directory doesn't contain any %-escapes.  */
 383       || (free_it = gethomedir (),
 384           ((file = search_magic_path (free_it, class, "%L/%N", 0))
 385            || (file = search_magic_path (free_it, class, "%N", 0)))))
 386     {
 387       XrmDatabase db = XrmGetFileDatabase (file);
 388       xfree (file);
 389       xfree (free_it);
 390       return db;
 391     }
 392
 393   xfree (free_it);
 394   return NULL;
 395 }
 396
 397
 398 static XrmDatabase
 399 get_user_db (Display *display)
 400 {
 401   XrmDatabase db;
 402   char *xdefs;
 403
 404 #ifdef PBaseSize                /* Cheap way to test for X11R4 or later.  */
 405   xdefs = XResourceManagerString (display);
 406 #else
 407   xdefs = display->xdefaults;
 408 #endif
 409
 410   if (xdefs != NULL)
 411     db = XrmGetStringDatabase (xdefs);
 412   else
 413     {
 414       char *home;
 415       char *xdefault;
 416
 417       home = gethomedir ();
 418       xdefault = (char *) xmalloc (strlen (home) + sizeof (".Xdefaults"));
 419       strcpy (xdefault, home);
 420       strcat (xdefault, ".Xdefaults");
 421       db = XrmGetFileDatabase (xdefault);
 422       xfree (home);
 423       xfree (xdefault);
 424     }
 425
 426 #ifdef HAVE_XSCREENRESOURCESTRING
 427   /* Get the screen-specific resources too.  */
 428   xdefs = XScreenResourceString (DefaultScreenOfDisplay (display));
 429   if (xdefs != NULL)
 430     {
 431       XrmMergeDatabases (XrmGetStringDatabase (xdefs), &db);
 432       XFree (xdefs);
 433     }
 434 #endif
 435
 436   return db;
 437 }
 438
 439 static XrmDatabase
 440 get_environ_db (void)
 441 {
 442   XrmDatabase db;
 443   char *p;
 444   char *path = 0, *home = 0;
 445   const char *host;
 446
 447   if ((p = getenv ("XENVIRONMENT")) == NULL)
 448     {
 449       home = gethomedir ();
 450       host = get_system_name ();
 451       path = (char *) xmalloc (strlen (home)
 452                               + sizeof (".Xdefaults-")
 453                               + strlen (host));
 454       sprintf (path, "%s%s%s", home, ".Xdefaults-", host);
 455       p = path;
 456     }
 457
 458   db = XrmGetFileDatabase (p);
 459
 460   xfree (path);
 461   xfree (home);
 462
 463   return db;
 464 }
 465 \f
 466 /* External interface.  */
 467
 468 /* Types of values that we can find in a database */
 469
 470 #define XrmStringType "String"  /* String representation */
 471 XrmRepresentation x_rm_string;  /* Quark representation */
 472
 473 /* Load X resources based on the display and a possible -xrm option. */
 474
 475 XrmDatabase
 476 x_load_resources (Display *display, const char *xrm_string,
 477                   const char *myname, const char *myclass)
 478 {
 479   XrmDatabase user_database;
 480   XrmDatabase rdb;
 481   XrmDatabase db;
 482   char line[256];
 483
 484   const char *helv = "-*-helvetica-medium-r-*--*-120-*-*-*-*-iso8859-1";
 485
 486 #ifdef USE_MOTIF
 487   const char *courier = "-*-courier-medium-r-*-*-*-120-*-*-*-*-iso8859-1";
 488 #endif
 489
 490   x_rm_string = XrmStringToQuark (XrmStringType);
 491 #ifndef USE_X_TOOLKIT
 492   /* pmr@osf.org says this shouldn't be done if USE_X_TOOLKIT.
 493      I suspect it's because the toolkit version does this elsewhere.  */
 494   XrmInitialize ();
 495 #endif
 496   rdb = XrmGetStringDatabase ("");
 497
 498   /* Add some font defaults.  If the font `helv' doesn't exist, widgets
 499      will use some other default font.  */
 500 #ifdef USE_MOTIF
 501
 502   sprintf (line, "%s.pane.background: grey75", myclass);
 503   XrmPutLineResource (&rdb, line);
 504   sprintf (line, "%s*fontList: %s", myclass, helv);
 505   XrmPutLineResource (&rdb, line);
 506   sprintf (line, "%s*menu*background: grey75", myclass);
 507   XrmPutLineResource (&rdb, line);
 508   sprintf (line, "%s*menubar*background: grey75", myclass);
 509   XrmPutLineResource (&rdb, line);
 510   sprintf (line, "%s*verticalScrollBar.background: grey75", myclass);
 511   XrmPutLineResource (&rdb, line);
 512   sprintf (line, "%s*verticalScrollBar.troughColor: grey75", myclass);
 513   XrmPutLineResource (&rdb, line);
 514   sprintf (line, "%s.dialog*.background: grey75", myclass);
 515   XrmPutLineResource (&rdb, line);
 516   sprintf (line, "%s*fsb.Text.background: white", myclass);
 517   XrmPutLineResource (&rdb, line);
 518   sprintf (line, "%s*fsb.FilterText.background: white", myclass);
 519   XrmPutLineResource (&rdb, line);
 520   sprintf (line, "%s*fsb*DirList.background: white", myclass);
 521   XrmPutLineResource (&rdb, line);
 522   sprintf (line, "%s*fsb*ItemsList.background: white", myclass);
 523   XrmPutLineResource (&rdb, line);
 524   sprintf (line, "%s*fsb*background: grey75", myclass);
 525   XrmPutLineResource (&rdb, line);
 526   sprintf (line, "%s*fsb.Text.fontList: %s", myclass, courier);
 527   XrmPutLineResource (&rdb, line);
 528   sprintf (line, "%s*fsb.FilterText.fontList: %s", myclass, courier);
 529   XrmPutLineResource (&rdb, line);
 530   sprintf (line, "%s*fsb*ItemsList.fontList: %s", myclass, courier);
 531   XrmPutLineResource (&rdb, line);
 532   sprintf (line, "%s*fsb*DirList.fontList: %s", myclass, courier);
 533   XrmPutLineResource (&rdb, line);
 534
 535   /* Set double click time of list boxes in the file selection
 536      dialog from `double-click-time'.  */
 537   if (INTEGERP (Vdouble_click_time) && XINT (Vdouble_click_time) > 0)
 538     {
 539       sprintf (line, "%s*fsb*DirList.doubleClickInterval: %d",
 540                myclass, XFASTINT (Vdouble_click_time));
 541       XrmPutLineResource (&rdb, line);
 542       sprintf (line, "%s*fsb*ItemsList.doubleClickInterval: %d",
 543                myclass, XFASTINT (Vdouble_click_time));
 544       XrmPutLineResource (&rdb, line);
 545     }
 546
 547 #else /* not USE_MOTIF */
 548
 549   sprintf (line, "Emacs.dialog*.background: grey75");
 550   XrmPutLineResource (&rdb, line);
 551 #if !defined (HAVE_XFT) || !defined (USE_LUCID)
 552   sprintf (line, "Emacs.dialog*.font: %s", helv);
 553   XrmPutLineResource (&rdb, line);
 554   sprintf (line, "*XlwMenu*font: %s", helv);
 555   XrmPutLineResource (&rdb, line);
 556 #endif
 557   sprintf (line, "*XlwMenu*background: grey75");
 558   XrmPutLineResource (&rdb, line);
 559   sprintf (line, "Emacs*verticalScrollBar.background: grey75");
 560   XrmPutLineResource (&rdb, line);
 561
 562 #endif /* not USE_MOTIF */
 563
 564   user_database = get_user_db (display);
 565
 566   /* Figure out what the "customization string" is, so we can use it
 567      to decode paths.  */
 568   xfree (x_customization_string);
 569   x_customization_string
 570     = x_get_customization_string (user_database, myname, myclass);
 571
 572   /* Get application system defaults */
 573   db = get_system_app (myclass);
 574   if (db != NULL)
 575     XrmMergeDatabases (db, &rdb);
 576
 577   /* Get Fallback resources */
 578   db = get_fallback (display);
 579   if (db != NULL)
 580     XrmMergeDatabases (db, &rdb);
 581
 582   /* Get application user defaults */
 583   db = get_user_app (myclass);
 584   if (db != NULL)
 585     XrmMergeDatabases (db, &rdb);
 586
 587   /* get User defaults */
 588   if (user_database != NULL)
 589     XrmMergeDatabases (user_database, &rdb);
 590
 591   /* Get Environment defaults. */
 592   db = get_environ_db ();
 593   if (db != NULL)
 594     XrmMergeDatabases (db, &rdb);
 595
 596   /* Last, merge in any specification from the command line. */
 597   if (xrm_string != NULL)
 598     {
 599       db = XrmGetStringDatabase (xrm_string);
 600       if (db != NULL)
 601         XrmMergeDatabases (db, &rdb);
 602     }
 603
 604   return rdb;
 605 }
 606
 607
 608 /* Retrieve the value of the resource specified by NAME with class CLASS
 609    and of type TYPE from database RDB.  The value is returned in RET_VALUE. */
 610
 611 static int
 612 x_get_resource (XrmDatabase rdb, const char *name, const char *class,
 613                 XrmRepresentation expected_type, XrmValue *ret_value)
 614 {
 615   XrmValue value;
 616   XrmName namelist[100];
 617   XrmClass classlist[100];
 618   XrmRepresentation type;
 619
 620   XrmStringToNameList(name, namelist);
 621   XrmStringToClassList(class, classlist);
 622
 623   if (XrmQGetResource (rdb, namelist, classlist, &type, &value) == True
 624       && (type == expected_type))
 625     {
 626       if (type == x_rm_string)
 627         ret_value->addr = (char *) value.addr;
 628       else
 629         memcpy (ret_value->addr, value.addr, ret_value->size);
 630
 631       return value.size;
 632     }
 633
 634   return 0;
 635 }
 636
 637 /* Retrieve the string resource specified by NAME with CLASS from
 638    database RDB. */
 639
 640 char *
 641 x_get_string_resource (XrmDatabase rdb, const char *name, const char *class)
 642 {
 643   XrmValue value;
 644
 645   if (inhibit_x_resources)
 646     /* --quick was passed, so this is a no-op.  */
 647     return NULL;
 648
 649   if (x_get_resource (rdb, name, class, x_rm_string, &value))
 650     return (char *) value.addr;
 651
 652   return (char *) 0;
 653 }
 654 \f
 655 /* Stand-alone test facilities.  */
 656
 657 #ifdef TESTRM
 658
 659 typedef char **List;
 660 #define arg_listify(len, list) (list)
 661 #define car(list) (*(list))
 662 #define cdr(list) (list + 1)
 663 #define NIL(list) (! *(list))
 664 #define free_arglist(list)
 665
 666 static List
 667 member (elt, list)
 668      char *elt;
 669      List list;
 670 {
 671   List p;
 672
 673   for (p = list; ! NIL (p); p = cdr (p))
 674     if (! strcmp (elt, car (p)))
 675       return p;
 676
 677   return p;
 678 }
 679
 680 static void
 681 fatal (msg, prog, x1, x2, x3, x4, x5)
 682     char *msg, *prog;
 683     int x1, x2, x3, x4, x5;
 684 {
 685     if (errno)
 686       perror (prog);
 687
 688     (void) fprintf (stderr, msg, prog, x1, x2, x3, x4, x5);
 689     exit (1);
 690 }
 691
 692 main (argc, argv)
 693     int argc;
 694     char **argv;
 695 {
 696   Display *display;
 697   char *displayname, *resource_string, *class, *name;
 698   XrmDatabase xdb;
 699   List arg_list, lp;
 700
 701   arg_list = arg_listify (argc, argv);
 702
 703   lp = member ("-d", arg_list);
 704   if (!NIL (lp))
 705     displayname = car (cdr (lp));
 706   else
 707     displayname = "localhost:0.0";
 708
 709   lp = member ("-xrm", arg_list);
 710   if (! NIL (lp))
 711     resource_string = car (cdr (lp));
 712   else
 713     resource_string = (char *) 0;
 714
 715   lp = member ("-c", arg_list);
 716   if (! NIL (lp))
 717     class = car (cdr (lp));
 718   else
 719     class = "Emacs";
 720
 721   lp = member ("-n", arg_list);
 722   if (! NIL (lp))
 723     name = car (cdr (lp));
 724   else
 725     name = "emacs";
 726
 727   free_arglist (arg_list);
 728
 729   if (!(display = XOpenDisplay (displayname)))
 730     fatal ("Can't open display '%s'\n", XDisplayName (displayname));
 731
 732   xdb = x_load_resources (display, resource_string, name, class);
 733
 734   /* In a real program, you'd want to also do this: */
 735   display->db = xdb;
 736
 737   while (1)
 738     {
 739       char query_name[90];
 740       char query_class[90];
 741
 742       printf ("Name: ");
 743       gets (query_name);
 744
 745       if (strlen (query_name))
 746         {
 747           char *value;
 748
 749           printf ("Class: ");
 750           gets (query_class);
 751
 752           value = x_get_string_resource (xdb, query_name, query_class);
 753
 754           if (value != NULL)
 755             printf ("\t%s(%s):  %s\n\n", query_name, query_class, value);
 756           else
 757             printf ("\tNo Value.\n\n");
 758         }
 759       else
 760         break;
 761     }
 762   printf ("\tExit.\n\n");
 763
 764   XCloseDisplay (display);
 765 }
 766 #endif /* TESTRM */
 767