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