xrdb.c   [plain text]

/* Deal with the X Resource Manager.
   Copyright (C) 1990, 1993, 1994, 2000, 2001, 2002, 2003, 2004,
                 2005, 2006, 2007 Free Software Foundation, Inc.

This file is part of GNU Emacs.

GNU Emacs is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.

GNU Emacs is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with GNU Emacs; see the file COPYING.  If not, write to
the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
Boston, MA 02110-1301, USA.  */

/* Written by jla, 4/90 */

#ifdef emacs
#include <config.h>
#endif

#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif

#include <epaths.h>

#include <stdio.h>

#if 1 /* I'd really appreciate it if this code could go away...  -JimB */
/* This avoids lossage in the `dual-universe' headers on AT&T SysV
   X11.  Don't do it on Solaris, because it breaks compilation with
   XFree86 4.0.3 (and probably many other X11R6 releases) on Solaris
   2 */
#if defined(USG5) && !defined(SOLARIS2)
#ifndef SYSV
#define SYSV
#endif
#endif /* USG5 && !SOLARIS2 */

#endif /* 1 */

#include <X11/Xlib.h>
#include <X11/Xatom.h>
#if 0
#include <X11/Xos.h>
#endif
#include <X11/X.h>
#include <X11/Xutil.h>
#include <X11/Xresource.h>
#ifdef HAVE_PWD_H
#include <pwd.h>
#endif
#include <sys/stat.h>

#if !defined(S_ISDIR) && defined(S_IFDIR)
#define S_ISDIR(m) (((m) & S_IFMT) == S_IFDIR)
#endif

#include "lisp.h"

extern char *getenv ();

/* This does cause trouble on AIX.  I'm going to take the comment at
   face value.  */
#if 0
extern short getuid ();		/* If this causes portability problems,
				   I think we should just delete it; it'll
				   default to `int' anyway.  */
#endif

#ifdef DECLARE_GETPWUID_WITH_UID_T
extern struct passwd *getpwuid (uid_t);
extern struct passwd *getpwnam (const char *);
#else
extern struct passwd *getpwuid ();
extern struct passwd *getpwnam ();
#endif

extern char *get_system_name ();

/* Make sure not to #include anything after these definitions.  Let's
   not step on anyone's prototypes.  */
#ifdef emacs
/* darwin.h may have already defined these.  */
#undef malloc
#undef realloc
#undef free
#define malloc xmalloc
#define realloc xrealloc
#define free xfree
#endif

char *x_get_string_resource ();
static int file_p ();


/* X file search path processing.  */


/* The string which gets substituted for the %C escape in XFILESEARCHPATH
   and friends, or zero if none was specified.  */
char *x_customization_string;


/* Return the value of the emacs.customization (Emacs.Customization)
   resource, for later use in search path decoding.  If we find no
   such resource, return zero.  */
char *
x_get_customization_string (db, name, class)
     XrmDatabase db;
     char *name, *class;
{
  char *full_name
    = (char *) alloca (strlen (name) + sizeof ("customization") + 3);
  char *full_class
    = (char *) alloca (strlen (class) + sizeof ("Customization") + 3);
  char *result;

  sprintf (full_name,  "%s.%s", name,  "customization");
  sprintf (full_class, "%s.%s", class, "Customization");

  result = x_get_string_resource (db, full_name, full_class);

  if (result)
    {
      char *copy = (char *) malloc (strlen (result) + 1);
      strcpy (copy, result);
      return copy;
    }
  else
    return 0;
}


/* Expand all the Xt-style %-escapes in STRING, whose length is given
   by STRING_LEN.  Here are the escapes we're supposed to recognize:

	%N	The value of the application's class name
	%T	The value of the type parameter ("app-defaults" in this
		context)
	%S	The value of the suffix parameter ("" in this context)
	%L	The language string associated with the specified display
		(We use the "LANG" environment variable here, if it's set.)
	%l	The language part of the display's language string
		(We treat this just like %L.  If someone can tell us what
		 we're really supposed to do, dandy.)
	%t	The territory part of the display's language string
	        (This never gets used.)
	%c	The codeset part of the display's language string
	        (This never gets used either.)
	%C	The customization string retrieved from the resource
		database associated with display.
		(This is x_customization_string.)

   Return the expanded file name if it exists and is readable, and
   refers to %L only when the LANG environment variable is set, or
   otherwise provided by X.

   ESCAPED_SUFFIX and SUFFIX are postpended to STRING if they are
   non-zero.  %-escapes in ESCAPED_SUFFIX are expanded; STRING is left
   alone.

   Return NULL otherwise.  */

static char *
magic_file_p (string, string_len, class, escaped_suffix, suffix)
     char *string;
     int string_len;
     char *class, *escaped_suffix, *suffix;
{
  char *lang = getenv ("LANG");

  int path_size = 100;
  char *path = (char *) malloc (path_size);
  int path_len = 0;

  char *p = string;

  while (p < string + string_len)
    {
      /* The chunk we're about to stick on the end of result.  */
      char *next = NULL;
      int next_len;

      if (*p == '%')
	{
	  p++;

	  if (p >= string + string_len)
	    next_len = 0;
	  else
	    switch (*p)
	      {
	      case '%':
		next = "%";
		next_len = 1;
		break;

	      case 'C':
		next = (x_customization_string
			? x_customization_string
			: "");
		next_len = strlen (next);
		break;

	      case 'N':
		next = class;
		next_len = strlen (class);
		break;

	      case 'T':
		next = "app-defaults";
		next_len = strlen (next);
		break;

	      default:
	      case 'S':
		next_len = 0;
		break;

	      case 'L':
	      case 'l':
		if (! lang)
		  {
		    free (path);
		    return NULL;
		  }

		next = lang;
		next_len = strlen (next);
		break;

	      case 't':
	      case 'c':
		free (path);
		return NULL;
	      }
	}
      else
	next = p, next_len = 1;

      /* Do we have room for this component followed by a '\0' ?  */
      if (path_len + next_len + 1 > path_size)
	{
	  path_size = (path_len + next_len + 1) * 2;
	  path = (char *) realloc (path, path_size);
	}

      bcopy (next, path + path_len, next_len);
      path_len += next_len;

      p++;

      /* If we've reached the end of the string, append ESCAPED_SUFFIX.  */
      if (p >= string + string_len && escaped_suffix)
	{
	  string = escaped_suffix;
	  string_len = strlen (string);
	  p = string;
	  escaped_suffix = NULL;
	}
    }

  /* Perhaps we should add the SUFFIX now.  */
  if (suffix)
    {
      int suffix_len = strlen (suffix);

      if (path_len + suffix_len + 1 > path_size)
	{
	  path_size = (path_len + suffix_len + 1);
	  path = (char *) realloc (path, path_size);
	}

      bcopy (suffix, path + path_len, suffix_len);
      path_len += suffix_len;
    }

  path[path_len] = '\0';

  if (! file_p (path))
    {
      free (path);
      return NULL;
    }

  return path;
}


static char *
gethomedir ()
{
  struct passwd *pw;
  char *ptr;
  char *copy;

  if ((ptr = getenv ("HOME")) == NULL)
    {
      if ((ptr = getenv ("LOGNAME")) != NULL
	  || (ptr = getenv ("USER")) != NULL)
	pw = getpwnam (ptr);
      else
	pw = getpwuid (getuid ());

      if (pw)
	ptr = pw->pw_dir;
    }

  if (ptr == NULL)
    return xstrdup ("/");

  copy = (char *) malloc (strlen (ptr) + 2);
  strcpy (copy, ptr);
  strcat (copy, "/");

  return copy;
}


static int
file_p (filename)
     char *filename;
{
  struct stat status;

  return (access (filename, 4) == 0             /* exists and is readable */
	  && stat (filename, &status) == 0	/* get the status */
	  && (S_ISDIR (status.st_mode)) == 0);	/* not a directory */
}


/* Find the first element of SEARCH_PATH which exists and is readable,
   after expanding the %-escapes.  Return 0 if we didn't find any, and
   the path name of the one we found otherwise.  */

static char *
search_magic_path (search_path, class, escaped_suffix, suffix)
     char *search_path, *class, *escaped_suffix, *suffix;
{
  register char *s, *p;

  for (s = search_path; *s; s = p)
    {
      for (p = s; *p && *p != ':'; p++)
	;

      if (p > s)
	{
	  char *path = magic_file_p (s, p - s, class, escaped_suffix, suffix);
	  if (path)
	    return path;
	}
      else if (*p == ':')
	{
	  char *path;

	  s = "%N%S";
	  path = magic_file_p (s, strlen (s), class, escaped_suffix, suffix);
	  if (path)
	    return path;
	}

      if (*p == ':')
	p++;
    }

  return 0;
}

/* Producing databases for individual sources.  */

static XrmDatabase
get_system_app (class)
     char *class;
{
  XrmDatabase db = NULL;
  char *path;

  path = getenv ("XFILESEARCHPATH");
  if (! path) path = PATH_X_DEFAULTS;

  path = search_magic_path (path, class, 0, 0);
  if (path)
    {
      db = XrmGetFileDatabase (path);
      free (path);
    }

  return db;
}


static XrmDatabase
get_fallback (display)
     Display *display;
{
  return NULL;
}


static XrmDatabase
get_user_app (class)
     char *class;
{
  char *path;
  char *file = 0;
  char *free_it = 0;

  /* Check for XUSERFILESEARCHPATH.  It is a path of complete file
     names, not directories.  */
  if (((path = getenv ("XUSERFILESEARCHPATH"))
       && (file = search_magic_path (path, class, 0, 0)))

      /* Check for APPLRESDIR; it is a path of directories.  In each,
	 we have to search for LANG/CLASS and then CLASS.  */
      || ((path = getenv ("XAPPLRESDIR"))
	  && ((file = search_magic_path (path, class, "/%L/%N", 0))
	      || (file = search_magic_path (path, class, "/%N", 0))))

      /* Check in the home directory.  This is a bit of a hack; let's
	 hope one's home directory doesn't contain any %-escapes.  */
      || (free_it = gethomedir (),
	  ((file = search_magic_path (free_it, class, "%L/%N", 0))
	   || (file = search_magic_path (free_it, class, "%N", 0)))))
    {
      XrmDatabase db = XrmGetFileDatabase (file);
      free (file);
      if (free_it)
	free (free_it);
      return db;
    }

  if (free_it)
    free (free_it);
  return NULL;
}


static XrmDatabase
get_user_db (display)
     Display *display;
{
  XrmDatabase db;
  char *xdefs;

#ifdef PBaseSize		/* Cheap way to test for X11R4 or later.  */
  xdefs = XResourceManagerString (display);
#else
  xdefs = display->xdefaults;
#endif

  if (xdefs != NULL)
    db = XrmGetStringDatabase (xdefs);
  else
    {
      char *home;
      char *xdefault;

      home = gethomedir ();
      xdefault = (char *) malloc (strlen (home) + sizeof (".Xdefaults"));
      strcpy (xdefault, home);
      strcat (xdefault, ".Xdefaults");
      db = XrmGetFileDatabase (xdefault);
      free (home);
      free (xdefault);
    }

#ifdef HAVE_XSCREENRESOURCESTRING
  /* Get the screen-specific resources too.  */
  xdefs = XScreenResourceString (DefaultScreenOfDisplay (display));
  if (xdefs != NULL)
    {
      XrmMergeDatabases (XrmGetStringDatabase (xdefs), &db);
      XFree (xdefs);
    }
#endif

  return db;
}

static XrmDatabase
get_environ_db ()
{
  XrmDatabase db;
  char *p;
  char *path = 0, *home = 0, *host;

  if ((p = getenv ("XENVIRONMENT")) == NULL)
    {
      home = gethomedir ();
      host = get_system_name ();
      path = (char *) malloc (strlen (home)
			      + sizeof (".Xdefaults-")
			      + strlen (host));
      sprintf (path, "%s%s%s", home, ".Xdefaults-", host);
      p = path;
    }

  db = XrmGetFileDatabase (p);

  if (path) free (path);
  if (home) free (home);

  return db;
}

/* External interface.  */

/* Types of values that we can find in a database */

#define XrmStringType "String"	/* String representation */
XrmRepresentation x_rm_string;	/* Quark representation */

/* Load X resources based on the display and a possible -xrm option. */

XrmDatabase
x_load_resources (display, xrm_string, myname, myclass)
     Display *display;
     char *xrm_string, *myname, *myclass;
{
  XrmDatabase user_database;
  XrmDatabase rdb;
  XrmDatabase db;
  char line[256];

  char *helv = "-*-helvetica-medium-r-*--*-120-*-*-*-*-iso8859-1";

#ifdef USE_MOTIF
  char *courier = "-*-courier-medium-r-*-*-*-120-*-*-*-*-iso8859-1";
  extern Lisp_Object Vdouble_click_time;
#endif

  x_rm_string = XrmStringToQuark (XrmStringType);
#ifndef USE_X_TOOLKIT
  /* pmr@osf.org says this shouldn't be done if USE_X_TOOLKIT.
     I suspect it's because the toolkit version does this elsewhere.  */
  XrmInitialize ();
#endif
  rdb = XrmGetStringDatabase ("");

  /* Add some font defaults.  If the font `helv' doesn't exist, widgets
     will use some other default font.  */
#ifdef USE_MOTIF

  sprintf (line, "%s.pane.background: grey75", myclass);
  XrmPutLineResource (&rdb, line);
  sprintf (line, "%s*fontList: %s", myclass, helv);
  XrmPutLineResource (&rdb, line);
  sprintf (line, "%s*menu*background: grey75", myclass);
  XrmPutLineResource (&rdb, line);
  sprintf (line, "%s*menubar*background: grey75", myclass);
  XrmPutLineResource (&rdb, line);
  sprintf (line, "%s*verticalScrollBar.background: grey75", myclass);
  XrmPutLineResource (&rdb, line);
  sprintf (line, "%s*verticalScrollBar.troughColor: grey75", myclass);
  XrmPutLineResource (&rdb, line);
  sprintf (line, "%s.dialog*.background: grey75", myclass);
  XrmPutLineResource (&rdb, line);
  sprintf (line, "%s*fsb.Text.background: white", myclass);
  XrmPutLineResource (&rdb, line);
  sprintf (line, "%s*fsb.FilterText.background: white", myclass);
  XrmPutLineResource (&rdb, line);
  sprintf (line, "%s*fsb*DirList.background: white", myclass);
  XrmPutLineResource (&rdb, line);
  sprintf (line, "%s*fsb*ItemsList.background: white", myclass);
  XrmPutLineResource (&rdb, line);
  sprintf (line, "%s*fsb*background: grey75", myclass);
  XrmPutLineResource (&rdb, line);
  sprintf (line, "%s*fsb.Text.fontList: %s", myclass, courier);
  XrmPutLineResource (&rdb, line);
  sprintf (line, "%s*fsb.FilterText.fontList: %s", myclass, courier);
  XrmPutLineResource (&rdb, line);
  sprintf (line, "%s*fsb*ItemsList.fontList: %s", myclass, courier);
  XrmPutLineResource (&rdb, line);
  sprintf (line, "%s*fsb*DirList.fontList: %s", myclass, courier);
  XrmPutLineResource (&rdb, line);

  /* Set double click time of list boxes in the file selection
     dialog from `double-click-time'.  */
  if (INTEGERP (Vdouble_click_time) && XINT (Vdouble_click_time) > 0)
    {
      sprintf (line, "%s*fsb*DirList.doubleClickInterval: %d",
	       myclass, XFASTINT (Vdouble_click_time));
      XrmPutLineResource (&rdb, line);
      sprintf (line, "%s*fsb*ItemsList.doubleClickInterval: %d",
	       myclass, XFASTINT (Vdouble_click_time));
      XrmPutLineResource (&rdb, line);
    }

#else /* not USE_MOTIF */

  sprintf (line, "Emacs.dialog*.font: %s", helv);
  XrmPutLineResource (&rdb, line);
  sprintf (line, "Emacs.dialog*.background: grey75");
  XrmPutLineResource (&rdb, line);
  sprintf (line, "*XlwMenu*font: %s", helv);
  XrmPutLineResource (&rdb, line);
  sprintf (line, "*XlwMenu*background: grey75");
  XrmPutLineResource (&rdb, line);
  sprintf (line, "Emacs*verticalScrollBar.background: grey75");
  XrmPutLineResource (&rdb, line);

#endif /* not USE_MOTIF */

  user_database = get_user_db (display);

  /* Figure out what the "customization string" is, so we can use it
     to decode paths.  */
  if (x_customization_string)
    free (x_customization_string);
  x_customization_string
    = x_get_customization_string (user_database, myname, myclass);

  /* Get application system defaults */
  db = get_system_app (myclass);
  if (db != NULL)
    XrmMergeDatabases (db, &rdb);

  /* Get Fallback resources */
  db = get_fallback (display);
  if (db != NULL)
    XrmMergeDatabases (db, &rdb);

  /* Get application user defaults */
  db = get_user_app (myclass);
  if (db != NULL)
    XrmMergeDatabases (db, &rdb);

  /* get User defaults */
  if (user_database != NULL)
    XrmMergeDatabases (user_database, &rdb);

  /* Get Environment defaults. */
  db = get_environ_db ();
  if (db != NULL)
    XrmMergeDatabases (db, &rdb);

  /* Last, merge in any specification from the command line. */
  if (xrm_string != NULL)
    {
      db = XrmGetStringDatabase (xrm_string);
      if (db != NULL)
	XrmMergeDatabases (db, &rdb);
    }

  return rdb;
}


/* Retrieve the value of the resource specified by NAME with class CLASS
   and of type TYPE from database RDB.  The value is returned in RET_VALUE. */

int
x_get_resource (rdb, name, class, expected_type, ret_value)
     XrmDatabase rdb;
     char *name, *class;
     XrmRepresentation expected_type;
     XrmValue *ret_value;
{
  XrmValue value;
  XrmName namelist[100];
  XrmClass classlist[100];
  XrmRepresentation type;

  XrmStringToNameList(name, namelist);
  XrmStringToClassList(class, classlist);

  if (XrmQGetResource (rdb, namelist, classlist, &type, &value) == True
      && (type == expected_type))
    {
      if (type == x_rm_string)
	ret_value->addr = (char *) value.addr;
      else
	bcopy (value.addr, ret_value->addr, ret_value->size);

      return value.size;
    }

  return 0;
}

/* Retrieve the string resource specified by NAME with CLASS from
   database RDB. */

char *
x_get_string_resource (rdb, name, class)
     XrmDatabase rdb;
     char *name, *class;
{
  XrmValue value;

  if (x_get_resource (rdb, name, class, x_rm_string, &value))
    return (char *) value.addr;

  return (char *) 0;
}

/* Stand-alone test facilities.  */

#ifdef TESTRM

typedef char **List;
#define arg_listify(len, list) (list)
#define car(list) (*(list))
#define cdr(list) (list + 1)
#define NIL(list) (! *(list))
#define free_arglist(list)

static List
member (elt, list)
     char *elt;
     List list;
{
  List p;

  for (p = list; ! NIL (p); p = cdr (p))
    if (! strcmp (elt, car (p)))
      return p;

  return p;
}

static void
fatal (msg, prog, x1, x2, x3, x4, x5)
    char *msg, *prog;
    int x1, x2, x3, x4, x5;
{
    extern int errno;

    if (errno)
      perror (prog);

    (void) fprintf (stderr, msg, prog, x1, x2, x3, x4, x5);
    exit (1);
}

main (argc, argv)
    int argc;
    char **argv;
{
  Display *display;
  char *displayname, *resource_string, *class, *name;
  XrmDatabase xdb;
  List arg_list, lp;

  arg_list = arg_listify (argc, argv);

  lp = member ("-d", arg_list);
  if (!NIL (lp))
    displayname = car (cdr (lp));
  else
    displayname = "localhost:0.0";

  lp = member ("-xrm", arg_list);
  if (! NIL (lp))
    resource_string = car (cdr (lp));
  else
    resource_string = (char *) 0;

  lp = member ("-c", arg_list);
  if (! NIL (lp))
    class = car (cdr (lp));
  else
    class = "Emacs";

  lp = member ("-n", arg_list);
  if (! NIL (lp))
    name = car (cdr (lp));
  else
    name = "emacs";

  free_arglist (arg_list);

  if (!(display = XOpenDisplay (displayname)))
    fatal ("Can't open display '%s'\n", XDisplayName (displayname));

  xdb = x_load_resources (display, resource_string, name, class);

  /* In a real program, you'd want to also do this: */
  display->db = xdb;

  while (1)
    {
      char query_name[90];
      char query_class[90];

      printf ("Name: ");
      gets (query_name);

      if (strlen (query_name))
	{
	  char *value;

	  printf ("Class: ");
	  gets (query_class);

	  value = x_get_string_resource (xdb, query_name, query_class);

	  if (value != NULL)
	    printf ("\t%s(%s):  %s\n\n", query_name, query_class, value);
	  else
	    printf ("\tNo Value.\n\n");
	}
      else
	break;
    }
  printf ("\tExit.\n\n");

  XCloseDisplay (display);
}
#endif /* TESTRM */

/* arch-tag: 37e6fbab-ed05-4363-9e76-6c4109ed511f
   (do not change this comment) */