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