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