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