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