src/xrdb.c

   1 /* Deal with the X Resource Manager.
   2    Copyright (C) 1990, 1993-1994, 2000-2012 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 <fcntl.h>
  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   return (faccessat (AT_FDCWD, filename, R_OK, AT_EACCESS) == 0
 266           && ! file_directory_p (filename));
 267 }
 268
 269
 270 /* Find the first element of SEARCH_PATH which exists and is readable,
 271    after expanding the %-escapes.  Return 0 if we didn't find any, and
 272    the path name of the one we found otherwise.  */
 273
 274 static char *
 275 search_magic_path (const char *search_path, const char *class,
 276                    const char *escaped_suffix)
 277 {
 278   const char *s, *p;
 279
 280   for (s = search_path; *s; s = p)
 281     {
 282       for (p = s; *p && *p != ':'; p++)
 283         ;
 284
 285       if (p > s)
 286         {
 287           char *path = magic_file_p (s, p - s, class, escaped_suffix);
 288           if (path)
 289             return path;
 290         }
 291       else if (*p == ':')
 292         {
 293           char *path;
 294
 295           s = "%N%S";
 296           path = magic_file_p (s, strlen (s), class, escaped_suffix);
 297           if (path)
 298             return path;
 299         }
 300
 301       if (*p == ':')
 302         p++;
 303     }
 304
 305   return 0;
 306 }
 307 \f
 308 /* Producing databases for individual sources.  */
 309
 310 static XrmDatabase
 311 get_system_app (const char *class)
 312 {
 313   XrmDatabase db = NULL;
 314   const char *path;
 315   char *p;
 316
 317   path = getenv ("XFILESEARCHPATH");
 318   if (! path) path = PATH_X_DEFAULTS;
 319
 320   p = search_magic_path (path, class, 0);
 321   if (p)
 322     {
 323       db = XrmGetFileDatabase (p);
 324       xfree (p);
 325     }
 326
 327   return db;
 328 }
 329
 330
 331 static XrmDatabase
 332 get_fallback (Display *display)
 333 {
 334   return NULL;
 335 }
 336
 337
 338 static XrmDatabase
 339 get_user_app (const char *class)
 340 {
 341   const char *path;
 342   char *file = 0;
 343   char *free_it = 0;
 344
 345   /* Check for XUSERFILESEARCHPATH.  It is a path of complete file
 346      names, not directories.  */
 347   if (((path = getenv ("XUSERFILESEARCHPATH"))
 348        && (file = search_magic_path (path, class, 0)))
 349
 350       /* Check for APPLRESDIR; it is a path of directories.  In each,
 351          we have to search for LANG/CLASS and then CLASS.  */
 352       || ((path = getenv ("XAPPLRESDIR"))
 353           && ((file = search_magic_path (path, class, "/%L/%N"))
 354               || (file = search_magic_path (path, class, "/%N"))))
 355
 356       /* Check in the home directory.  This is a bit of a hack; let's
 357          hope one's home directory doesn't contain any %-escapes.  */
 358       || (free_it = gethomedir (),
 359           ((file = search_magic_path (free_it, class, "%L/%N"))
 360            || (file = search_magic_path (free_it, class, "%N")))))
 361     {
 362       XrmDatabase db = XrmGetFileDatabase (file);
 363       xfree (file);
 364       xfree (free_it);
 365       return db;
 366     }
 367
 368   xfree (free_it);
 369   return NULL;
 370 }
 371
 372
 373 static XrmDatabase
 374 get_user_db (Display *display)
 375 {
 376   XrmDatabase db;
 377   char *xdefs;
 378
 379 #ifdef PBaseSize                /* Cheap way to test for X11R4 or later.  */
 380   xdefs = XResourceManagerString (display);
 381 #else
 382   xdefs = display->xdefaults;
 383 #endif
 384
 385   if (xdefs != NULL)
 386     db = XrmGetStringDatabase (xdefs);
 387   else
 388     {
 389       char *home;
 390       char *xdefault;
 391
 392       home = gethomedir ();
 393       xdefault = xmalloc (strlen (home) + sizeof ".Xdefaults");
 394       strcpy (xdefault, home);
 395       strcat (xdefault, ".Xdefaults");
 396       db = XrmGetFileDatabase (xdefault);
 397       xfree (home);
 398       xfree (xdefault);
 399     }
 400
 401 #ifdef HAVE_XSCREENRESOURCESTRING
 402   /* Get the screen-specific resources too.  */
 403   xdefs = XScreenResourceString (DefaultScreenOfDisplay (display));
 404   if (xdefs != NULL)
 405     {
 406       XrmMergeDatabases (XrmGetStringDatabase (xdefs), &db);
 407       XFree (xdefs);
 408     }
 409 #endif
 410
 411   return db;
 412 }
 413
 414 static XrmDatabase
 415 get_environ_db (void)
 416 {
 417   XrmDatabase db;
 418   char *p;
 419   char *path = 0;
 420
 421   if ((p = getenv ("XENVIRONMENT")) == NULL)
 422     {
 423       static char const xdefaults[] = ".Xdefaults-";
 424       char *home = gethomedir ();
 425       char const *host = SSDATA (Vsystem_name);
 426       ptrdiff_t pathsize = (strlen (home) + sizeof xdefaults
 427                             + SBYTES (Vsystem_name));
 428       path = xrealloc (home, pathsize);
 429       strcat (strcat (path, xdefaults), host);
 430       p = path;
 431     }
 432
 433   db = XrmGetFileDatabase (p);
 434
 435   xfree (path);
 436
 437   return db;
 438 }
 439 \f
 440 /* External interface.  */
 441
 442 /* Types of values that we can find in a database */
 443
 444 #define XrmStringType "String"  /* String representation */
 445 static XrmRepresentation x_rm_string;   /* Quark representation */
 446
 447 /* Load X resources based on the display and a possible -xrm option. */
 448
 449 XrmDatabase
 450 x_load_resources (Display *display, const char *xrm_string,
 451                   const char *myname, const char *myclass)
 452 {
 453   XrmDatabase user_database;
 454   XrmDatabase rdb;
 455   XrmDatabase db;
 456   char line[256];
 457
 458 #if defined USE_MOTIF || !defined HAVE_XFT || !defined USE_LUCID
 459   const char *helv = "-*-helvetica-medium-r-*--*-120-*-*-*-*-iso8859-1";
 460 #endif
 461
 462 #ifdef USE_MOTIF
 463   const char *courier = "-*-courier-medium-r-*-*-*-120-*-*-*-*-iso8859-1";
 464 #endif
 465
 466   x_rm_string = XrmStringToQuark (XrmStringType);
 467 #ifndef USE_X_TOOLKIT
 468   /* pmr@osf.org says this shouldn't be done if USE_X_TOOLKIT.
 469      I suspect it's because the toolkit version does this elsewhere.  */
 470   XrmInitialize ();
 471 #endif
 472   rdb = XrmGetStringDatabase ("");
 473
 474   /* Add some font defaults.  If the font `helv' doesn't exist, widgets
 475      will use some other default font.  */
 476 #ifdef USE_MOTIF
 477
 478   sprintf (line, "%s.pane.background: grey75", myclass);
 479   XrmPutLineResource (&rdb, line);
 480   sprintf (line, "%s*fontList: %s", myclass, helv);
 481   XrmPutLineResource (&rdb, line);
 482   sprintf (line, "%s*menu*background: grey75", myclass);
 483   XrmPutLineResource (&rdb, line);
 484   sprintf (line, "%s*menubar*background: grey75", myclass);
 485   XrmPutLineResource (&rdb, line);
 486   sprintf (line, "%s*verticalScrollBar.background: grey75", myclass);
 487   XrmPutLineResource (&rdb, line);
 488   sprintf (line, "%s*verticalScrollBar.troughColor: grey75", myclass);
 489   XrmPutLineResource (&rdb, line);
 490   sprintf (line, "%s.dialog*.background: grey75", myclass);
 491   XrmPutLineResource (&rdb, line);
 492   sprintf (line, "%s*fsb.Text.background: white", myclass);
 493   XrmPutLineResource (&rdb, line);
 494   sprintf (line, "%s*fsb.FilterText.background: white", myclass);
 495   XrmPutLineResource (&rdb, line);
 496   sprintf (line, "%s*fsb*DirList.background: white", myclass);
 497   XrmPutLineResource (&rdb, line);
 498   sprintf (line, "%s*fsb*ItemsList.background: white", myclass);
 499   XrmPutLineResource (&rdb, line);
 500   sprintf (line, "%s*fsb*background: grey75", myclass);
 501   XrmPutLineResource (&rdb, line);
 502   sprintf (line, "%s*fsb.Text.fontList: %s", myclass, courier);
 503   XrmPutLineResource (&rdb, line);
 504   sprintf (line, "%s*fsb.FilterText.fontList: %s", myclass, courier);
 505   XrmPutLineResource (&rdb, line);
 506   sprintf (line, "%s*fsb*ItemsList.fontList: %s", myclass, courier);
 507   XrmPutLineResource (&rdb, line);
 508   sprintf (line, "%s*fsb*DirList.fontList: %s", myclass, courier);
 509   XrmPutLineResource (&rdb, line);
 510
 511   /* Set double click time of list boxes in the file selection
 512      dialog from `double-click-time'.  */
 513   if (INTEGERP (Vdouble_click_time) && XINT (Vdouble_click_time) > 0)
 514     {
 515       sprintf (line, "%s*fsb*DirList.doubleClickInterval: %"pI"d",
 516                myclass, XFASTINT (Vdouble_click_time));
 517       XrmPutLineResource (&rdb, line);
 518       sprintf (line, "%s*fsb*ItemsList.doubleClickInterval: %"pI"d",
 519                myclass, XFASTINT (Vdouble_click_time));
 520       XrmPutLineResource (&rdb, line);
 521     }
 522
 523 #else /* not USE_MOTIF */
 524
 525   sprintf (line, "Emacs.dialog*.background: grey75");
 526   XrmPutLineResource (&rdb, line);
 527 #if !defined (HAVE_XFT) || !defined (USE_LUCID)
 528   sprintf (line, "Emacs.dialog*.font: %s", helv);
 529   XrmPutLineResource (&rdb, line);
 530   sprintf (line, "*XlwMenu*font: %s", helv);
 531   XrmPutLineResource (&rdb, line);
 532 #endif
 533   sprintf (line, "*XlwMenu*background: grey75");
 534   XrmPutLineResource (&rdb, line);
 535   sprintf (line, "Emacs*verticalScrollBar.background: grey75");
 536   XrmPutLineResource (&rdb, line);
 537
 538 #endif /* not USE_MOTIF */
 539
 540   user_database = get_user_db (display);
 541
 542   /* Figure out what the "customization string" is, so we can use it
 543      to decode paths.  */
 544   xfree (x_customization_string);
 545   x_customization_string
 546     = x_get_customization_string (user_database, myname, myclass);
 547
 548   /* Get application system defaults */
 549   db = get_system_app (myclass);
 550   if (db != NULL)
 551     XrmMergeDatabases (db, &rdb);
 552
 553   /* Get Fallback resources */
 554   db = get_fallback (display);
 555   if (db != NULL)
 556     XrmMergeDatabases (db, &rdb);
 557
 558   /* Get application user defaults */
 559   db = get_user_app (myclass);
 560   if (db != NULL)
 561     XrmMergeDatabases (db, &rdb);
 562
 563   /* get User defaults */
 564   if (user_database != NULL)
 565     XrmMergeDatabases (user_database, &rdb);
 566
 567   /* Get Environment defaults. */
 568   db = get_environ_db ();
 569   if (db != NULL)
 570     XrmMergeDatabases (db, &rdb);
 571
 572   /* Last, merge in any specification from the command line. */
 573   if (xrm_string != NULL)
 574     {
 575       db = XrmGetStringDatabase (xrm_string);
 576       if (db != NULL)
 577         XrmMergeDatabases (db, &rdb);
 578     }
 579
 580   return rdb;
 581 }
 582
 583
 584 /* Retrieve the value of the resource specified by NAME with class CLASS
 585    and of type TYPE from database RDB.  The value is returned in RET_VALUE. */
 586
 587 static int
 588 x_get_resource (XrmDatabase rdb, const char *name, const char *class,
 589                 XrmRepresentation expected_type, XrmValue *ret_value)
 590 {
 591   XrmValue value;
 592   XrmName namelist[100];
 593   XrmClass classlist[100];
 594   XrmRepresentation type;
 595
 596   XrmStringToNameList (name, namelist);
 597   XrmStringToClassList (class, classlist);
 598
 599   if (XrmQGetResource (rdb, namelist, classlist, &type, &value) == True
 600       && (type == expected_type))
 601     {
 602       if (type == x_rm_string)
 603         ret_value->addr = (char *) value.addr;
 604       else
 605         memcpy (ret_value->addr, value.addr, ret_value->size);
 606
 607       return value.size;
 608     }
 609
 610   return 0;
 611 }
 612
 613 /* Retrieve the string resource specified by NAME with CLASS from
 614    database RDB. */
 615
 616 char *
 617 x_get_string_resource (XrmDatabase rdb, const char *name, const char *class)
 618 {
 619   XrmValue value;
 620
 621   if (inhibit_x_resources)
 622     /* --quick was passed, so this is a no-op.  */
 623     return NULL;
 624
 625   if (x_get_resource (rdb, name, class, x_rm_string, &value))
 626     return (char *) value.addr;
 627
 628   return (char *) 0;
 629 }
 630 \f
 631 /* Stand-alone test facilities.  */
 632
 633 #ifdef TESTRM
 634
 635 typedef char **List;
 636 #define arg_listify(len, list) (list)
 637 #define car(list) (*(list))
 638 #define cdr(list) (list + 1)
 639 #define NIL(list) (! *(list))
 640 #define free_arglist(list)
 641
 642 static List
 643 member (char *elt, List list)
 644 {
 645   List p;
 646
 647   for (p = list; ! NIL (p); p = cdr (p))
 648     if (! strcmp (elt, car (p)))
 649       return p;
 650
 651   return p;
 652 }
 653
 654 static void
 655 fatal (char *msg, char *prog)
 656 {
 657   if (errno)
 658     perror (prog);
 659
 660   (void) fprintf (stderr, msg, prog);
 661   exit (1);
 662 }
 663
 664 int
 665 main (int argc, char **argv)
 666 {
 667   Display *display;
 668   char *displayname, *resource_string, *class, *name;
 669   XrmDatabase xdb;
 670   List arg_list, lp;
 671
 672   arg_list = arg_listify (argc, argv);
 673
 674   lp = member ("-d", arg_list);
 675   if (!NIL (lp))
 676     displayname = car (cdr (lp));
 677   else
 678     displayname = "localhost:0.0";
 679
 680   lp = member ("-xrm", arg_list);
 681   if (! NIL (lp))
 682     resource_string = car (cdr (lp));
 683   else
 684     resource_string = (char *) 0;
 685
 686   lp = member ("-c", arg_list);
 687   if (! NIL (lp))
 688     class = car (cdr (lp));
 689   else
 690     class = "Emacs";
 691
 692   lp = member ("-n", arg_list);
 693   if (! NIL (lp))
 694     name = car (cdr (lp));
 695   else
 696     name = "emacs";
 697
 698   free_arglist (arg_list);
 699
 700   if (!(display = XOpenDisplay (displayname)))
 701     fatal ("Can't open display '%s'\n", XDisplayName (displayname));
 702
 703   xdb = x_load_resources (display, resource_string, name, class);
 704
 705   /* In a real program, you'd want to also do this: */
 706   display->db = xdb;
 707
 708   while (1)
 709     {
 710       char query_name[90];
 711       char query_class[90];
 712
 713       printf ("Name: ");
 714       gets (query_name);
 715
 716       if (strlen (query_name))
 717         {
 718           char *value;
 719
 720           printf ("Class: ");
 721           gets (query_class);
 722
 723           value = x_get_string_resource (xdb, query_name, query_class);
 724
 725           if (value != NULL)
 726             printf ("\t%s(%s):  %s\n\n", query_name, query_class, value);
 727           else
 728             printf ("\tNo Value.\n\n");
 729         }
 730       else
 731         break;
 732     }
 733   printf ("\tExit.\n\n");
 734
 735   XCloseDisplay (display);
 736
 737   return 0;
 738 }
 739 #endif /* TESTRM */