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