src/xrdb.c

   1 /* Deal with the X Resource Manager.
   2    Copyright (C) 1990, 1993 Free Software Foundation.
   3
   4 This program is free software; you can redistribute it and/or modify
   5 it under the terms of the GNU General Public License as published by
   6 the Free Software Foundation; either version 2, or (at your option)
   7 any later version.
   8
   9 This program is distributed in the hope that it will be useful,
  10 but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 GNU General Public License for more details.
  13
  14 You should have received a copy of the GNU General Public License
  15 along with this program; see the file COPYING.  If not, write to
  16 the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.  */
  17
  18 /* Written by jla, 4/90 */
  19
  20 #ifdef emacs
  21 #include "config.h"
  22 #endif
  23
  24 #if 1 /* I'd really appreciate it if this code could go away...  -JimB */
  25 /* this avoids lossage in the `dual-universe' headers on AT&T SysV X11 */
  26 #ifdef USG5
  27 #define SYSV
  28 #include <unistd.h>
  29 #endif /* USG5 */
  30
  31 #endif /* 1 */
  32
  33 /* This should be included before the X include files; otherwise, we get
  34    warnings about redefining NULL under BSD 4.3.  */
  35 #include <sys/param.h>
  36
  37 #include <X11/Xlib.h>
  38 #include <X11/Xatom.h>
  39 #if 0
  40 #include <X11/Xos.h>
  41 #endif
  42 #include <X11/X.h>
  43 #include <X11/Xutil.h>
  44 #include <X11/Xresource.h>
  45 #ifdef VMS
  46 #include "vms-pwd.h"
  47 #else
  48 #include <pwd.h>
  49 #endif
  50 #include <sys/stat.h>
  51
  52 #ifndef MAXPATHLEN
  53 #define MAXPATHLEN      256
  54 #endif
  55
  56 extern char *getenv ();
  57
  58 /* This does cause trouble on AIX.  I'm going to take the comment at
  59    face value.  */
  60 #if 0
  61 extern short getuid ();         /* If this causes portability problems,
  62                                    I think we should just delete it; it'll
  63                                    default to `int' anyway.  */
  64 #endif
  65
  66 #ifdef __bsdi__
  67 extern struct passwd *getpwuid (uid_t);
  68 extern struct passwd *getpwnam (const char *);
  69 #else
  70 extern struct passwd *getpwuid ();
  71 extern struct passwd *getpwnam ();
  72 #endif
  73
  74 static char *
  75 gethomedir (dirname)
  76      char *dirname;
  77 {
  78   int uid;
  79   struct passwd *pw;
  80   char *ptr;
  81
  82   if ((ptr = getenv ("HOME")) == NULL)
  83     {
  84       if ((ptr = getenv ("USER")) != NULL)
  85         pw = getpwnam (ptr);
  86       else
  87         {
  88           uid = getuid ();
  89           pw = getpwuid (uid);
  90         }
  91       if (pw)
  92         ptr = pw->pw_dir;
  93       else
  94         {
  95           ptr = NULL;
  96           *dirname = '\0';
  97         }
  98     }
  99
 100   if (ptr != NULL)
 101     strcpy (dirname, ptr);
 102
 103   dirname += strlen (dirname);
 104   *dirname = '/';
 105   dirname++;
 106   *dirname = '\0';
 107
 108   return dirname;
 109 }
 110
 111 static int
 112 file_p (path)
 113      char *path;
 114 {
 115   struct stat status;
 116
 117   return (access (path, 4) == 0                 /* exists and is readable */
 118           && stat (path, &status) == 0          /* get the status */
 119           && (status.st_mode & S_IFDIR) == 0);  /* not a directory */
 120 }
 121
 122 #if 0
 123 #define X_DEFAULT_SEARCH_PATH "/usr/lib/X11/"
 124 #endif
 125
 126 /* Isn't this just disgusting? */
 127
 128 #define X_DEFAULT_SEARCH_PATH "/usr/lib/X11/%L/%T/%N%S:/usr/lib/X11/%l/%T/%N%S:/usr/lib/X11/%T/%N%S"
 129
 130 static int
 131 decode_magic (string, file, return_path)
 132      char *string, *file, *return_path;
 133 {
 134   char *p = string;
 135   char *t = return_path;
 136
 137   while (*p)
 138     {
 139       if (*p == '%')
 140         switch (*++p)
 141           {
 142           case '%':
 143             *t++ = '%';
 144             p++;
 145             break;
 146
 147           case 'N':
 148           case 'T':
 149           case 'S':
 150           case 'L':
 151           case 'l':
 152           case 't':
 153           case 'c':
 154           default:
 155             p++;
 156             if (*t == '/' && *p == '/')
 157               p++;
 158             break;
 159           }
 160       else
 161         *t++ = *p++;
 162     }
 163   *t = '\0';
 164   strcat (return_path, file);
 165
 166   if (file_p (return_path))
 167     return 1;
 168
 169   return_path[0] = '\0';
 170   return 0;
 171 }
 172
 173 static int
 174 magic_searchpath_decoder (incantation_string, file, return_path)
 175      char *incantation_string, *return_path, *file;
 176 {
 177   register char *s = incantation_string;
 178   register char *p;
 179
 180   /* Must be big enough for "%N%S".  */
 181   register int string_size = MAXPATHLEN;
 182   register char *string = (char *) alloca (string_size * sizeof (*string));
 183
 184   while (*s)
 185     {
 186       p = s;
 187
 188       while (*p && *p != ':')
 189         p++;
 190
 191       if (*p == ':' && *(p + 1) == ':')
 192         {
 193           /* We know string is big enough for this.  */
 194           bcopy ("%N%S", string, 5);
 195           if (decode_magic (string, file, return_path))
 196             return 1;
 197
 198           s = p + 1;
 199           continue;
 200         }
 201
 202       if (p > s)
 203         {
 204           int len = p - s;
 205
 206           if (string_size < len+1)
 207             {
 208               string_size = 2 * len;
 209               string = (char *) alloca (string_size * sizeof (*string));
 210             }
 211           bcopy (s, string, len);
 212           string[len] = '\0';
 213           if (decode_magic (string, file, return_path))
 214             return 1;
 215         }
 216
 217       if (p && *p != 0)
 218         s = p + 1;
 219       else
 220         return 0;
 221     }
 222
 223   return 0;
 224 }
 225 \f
 226 static XrmDatabase
 227 get_system_app (class)
 228      char *class;
 229 {
 230   XrmDatabase db;
 231   char path[MAXPATHLEN];
 232   char *p;
 233
 234   if ((p = getenv ("XFILESEARCHPATH")) == NULL)
 235     p = X_DEFAULT_SEARCH_PATH;
 236
 237   if (! magic_searchpath_decoder (p, class, path))
 238     return NULL;
 239
 240   db = XrmGetFileDatabase (path);
 241   return db;
 242 }
 243
 244 static XrmDatabase
 245 get_fallback (display)
 246      Display *display;
 247 {
 248   XrmDatabase db;
 249
 250   return NULL;
 251 }
 252
 253 static XrmDatabase
 254 get_user_app (class)
 255      char *class;
 256 {
 257   XrmDatabase db;
 258   char *magic_path;
 259   char path[MAXPATHLEN];
 260
 261   if ((magic_path = getenv ("XUSERFILESEARCHPATH")) == NULL)
 262     {
 263       char homedir[MAXPATHLEN];
 264       char *default_magic;
 265       char *p;
 266
 267       gethomedir (homedir);
 268
 269       if ((p = getenv ("XAPPLRESDIR")) == NULL)
 270         {
 271           default_magic = "%s/%%L/%%N:%s/%%l/%%N:%s/%%N";
 272           magic_path = (char *) alloca ((3 * strlen (homedir))
 273                                         + strlen (default_magic));
 274           sprintf (magic_path, default_magic, homedir, homedir, homedir);
 275         }
 276       else
 277         {
 278           default_magic = "%s/%%L/%%N:%s/%%l/%%N:%s/%%N:%s/%%N";
 279           magic_path = (char *) alloca ((3 * strlen (p))
 280                                         + strlen (default_magic)
 281                                         + strlen (homedir));
 282           sprintf (magic_path, default_magic, p, p, p, homedir);
 283         }
 284     }
 285
 286   if (! magic_searchpath_decoder (magic_path, class, path))
 287     return NULL;
 288
 289   db = XrmGetFileDatabase (path);
 290   return db;
 291 }
 292
 293 static XrmDatabase
 294 get_user_db (display)
 295      Display *display;
 296 {
 297   XrmDatabase db;
 298   char *xdefs;
 299
 300 #ifdef PBaseSize                /* Cheap way to test for X11R4 or later.  */
 301   xdefs = XResourceManagerString (display);
 302 #else
 303   xdefs = display->xdefaults;
 304 #endif
 305
 306   if (xdefs != NULL)
 307     db = XrmGetStringDatabase (xdefs);
 308   else
 309     {
 310       char xdefault[MAXPATHLEN];
 311
 312       gethomedir (xdefault);
 313       strcat (xdefault, ".Xdefaults");
 314       db = XrmGetFileDatabase (xdefault);
 315     }
 316
 317   return db;
 318 }
 319
 320 static XrmDatabase
 321 get_environ_db ()
 322 {
 323   XrmDatabase db;
 324   char *p;
 325   char path[MAXPATHLEN];
 326
 327   if ((p = getenv ("XENVIRONMENT")) == NULL)
 328     {
 329       gethomedir (path);
 330       strcat (path, ".Xdefaults-");
 331       gethostname (path + strlen (path), MAXPATHLEN - strlen (path));
 332       p = path;
 333     }
 334
 335   db = XrmGetFileDatabase (p);
 336   return db;
 337 }
 338 \f
 339 /* Types of values that we can find in a database */
 340
 341 #define XrmStringType "String"  /* String representation */
 342 XrmRepresentation x_rm_string;  /* Quark representation */
 343
 344 /* Load X resources based on the display and a possible -xrm option. */
 345
 346 XrmDatabase
 347 x_load_resources (display, xrm_string, myclass)
 348      Display *display;
 349      char *xrm_string, *myclass;
 350 {
 351   char *xdefs;
 352   XrmDatabase rdb;
 353   XrmDatabase db;
 354
 355   x_rm_string = XrmStringToQuark (XrmStringType);
 356   XrmInitialize ();
 357   rdb = XrmGetStringDatabase ("");
 358
 359   /* Get application system defaults */
 360   db = get_system_app (myclass);
 361   if (db != NULL)
 362     XrmMergeDatabases (db, &rdb);
 363
 364   /* Get Fallback resources */
 365   db = get_fallback (display);
 366   if (db != NULL)
 367     XrmMergeDatabases (db, &rdb);
 368
 369   /* Get application user defaults */
 370   db = get_user_app (myclass);
 371   if (db != NULL)
 372     XrmMergeDatabases (db, &rdb);
 373
 374   /* get User defaults */
 375   db = get_user_db (display);
 376   if (db != NULL)
 377     XrmMergeDatabases (db, &rdb);
 378
 379   /* Get Environment defaults. */
 380   db = get_environ_db ();
 381   if (db != NULL)
 382     XrmMergeDatabases (db, &rdb);
 383
 384   /* Last, merge in any specification from the command line. */
 385   if (xrm_string != NULL)
 386     {
 387       db = XrmGetStringDatabase (xrm_string);
 388       if (db != NULL)
 389         XrmMergeDatabases (db, &rdb);
 390     }
 391
 392   return rdb;
 393 }
 394
 395 /* Retrieve the value of the resource specified by NAME with class CLASS
 396    and of type TYPE from database RDB.  The value is returned in RET_VALUE. */
 397
 398 int
 399 x_get_resource (rdb, name, class, expected_type, ret_value)
 400      XrmDatabase rdb;
 401      char *name, *class;
 402      XrmRepresentation expected_type;
 403      XrmValue *ret_value;
 404 {
 405   XrmValue value;
 406   XrmName namelist[100];
 407   XrmClass classlist[100];
 408   XrmRepresentation type;
 409
 410   XrmStringToNameList(name, namelist);
 411   XrmStringToClassList(class, classlist);
 412
 413   if (XrmQGetResource (rdb, namelist, classlist, &type, &value) == True
 414       && (type == expected_type))
 415     {
 416       if (type == x_rm_string)
 417         ret_value->addr = (char *) value.addr;
 418       else
 419         bcopy (value.addr, ret_value->addr, ret_value->size);
 420
 421       return value.size;
 422     }
 423
 424   return 0;
 425 }
 426
 427 /* Retrieve the string resource specified by NAME with CLASS from
 428    database RDB. */
 429
 430 char *
 431 x_get_string_resource (rdb, name, class)
 432      XrmDatabase rdb;
 433      char *name, *class;
 434 {
 435   XrmValue value;
 436
 437   if (x_get_resource (rdb, name, class, x_rm_string, &value))
 438     return (char *) value.addr;
 439
 440   return (char *) 0;
 441 }
 442 \f
 443 #ifdef TESTRM
 444 #include <stdio.h>
 445 #include "arg-list.h"
 446
 447 static void
 448 fatal (msg, prog, x1, x2, x3, x4, x5)
 449     char *msg, *prog;
 450     int x1, x2, x3, x4, x5;
 451 {
 452     extern int errno;
 453
 454     if (errno)
 455       perror (prog);
 456
 457     (void) fprintf (stderr, msg, prog, x1, x2, x3, x4, x5);
 458     exit (1);
 459 }
 460
 461 main (argc, argv)
 462     int argc;
 463     char **argv;
 464 {
 465   Display *display;
 466   char *displayname, *resource_string, *class;
 467   XrmDatabase xdb;
 468   List *arg_list, *lp;
 469
 470   arg_list = arg_listify (argc, argv);
 471
 472   lp = member ("-d", arg_list);
 473   if (!NIL (lp))
 474     displayname = car (cdr (lp));
 475   else
 476     displayname = "localhost:0.0";
 477
 478   lp = member ("-xrm", arg_list);
 479   if (! NIL (lp))
 480     resource_string = car (cdr (lp));
 481   else
 482     resource_string = (char *) 0;
 483
 484   lp = member ("-c", arg_list);
 485   if (! NIL (lp))
 486     class = car (cdr (lp));
 487   else
 488     class = "Emacs";
 489
 490   free_arglist (arg_list);
 491
 492
 493
 494   if (!(display = XOpenDisplay (displayname)))
 495     fatal ("Can't open display '%s'\n", XDisplayName (displayname));
 496
 497   xdb = x_load_resources (display, resource_string, class);
 498
 499 #if 0
 500   /* In a real program, you'd want to also do this: */
 501   display->db = xdb;
 502 #endif
 503
 504   while (1)
 505     {
 506       char line[90];
 507
 508       printf ("String: ");
 509       gets (line);
 510       if (strlen (line))
 511         {
 512           char *value = x_get_string_resource (xdb, line, class);
 513
 514           if (value != NULL)
 515             printf ("\t%s:  %s\n\n", line, value);
 516           else
 517             printf ("\tNo Value.\n\n");
 518         }
 519       else
 520         break;
 521     }
 522   printf ("\tExit.\n\n");
 523
 524   XCloseDisplay (display);
 525 }
 526 #endif /* TESTRM */