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