Handle varalias chains, custom variables in #'user-variable-p. src/ChangeLog addition: 2008-08-23 Aidan Kehoe <kehoea@parhasard.net> * eval.c (Fuser_variable_p): Moved to symbols.c * symbols.c (Fcustom_variable_p): Moved here from custom.el. (user_variable_alias_check_fun): Mapper function used in `user-variable-p'. (Fuser_variable_p): Moved here from eval.c, to allow it to examine the variable alias chain. Expanded to check each entry in the variable alias chain for signs of being a user variable; documentation updated, noting the differences between GNU's behaviour and ours (ours is a little more sensible) (map_varalias_chain): New. Given a C function, call it at least once for each symbol in a symbol's varalias chain, signalling an error if there's a cycle, and returning immediately if the function returns something other than Qzero. (Fdefvaralias): Correct the use of the word "alias" in the docstring and in the argument name. Motivate this in a comment. Add support for a DOCSTRING argument, something GNU has too, and document this * gc.c (vars_of_gc): Start the docstring of `garbage-collection-messages' with an asterisk, to indicate that it's a user variable. lisp/ChangeLog addition: 2008-08-23 Aidan Kehoe <kehoea@parhasard.net> * custom.el: Move #'custom-variable-p to C, since it's now called from #'user-variable-p.

/*
 * Copyright (c) 2000, Red Hat, Inc.
 *
 *     This program 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 of the License, or
 *     (at your option) any later version.
 *
 *     A copy of the GNU General Public License can be found at
 *     http://www.gnu.org/
 *
 * Written by DJ Delorie <dj@cygnus.com>
 *
 */

/* The purpose of this file is to manage access to files stored on the
   local disk (i.e. "downloading" setup.ini).  Called from netio.cc */

#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <errno.h>
#include "win32.h"
#include "netio.h"
#include "nio-file.h"
#include "resource.h"
#include "msg.h"

NetIO_File::NetIO_File (char *Purl)
  : NetIO (Purl)
{
  struct stat s;
  fd = fopen (path, "rb");
  if (fd)
    {
      stat (path, &s);
      file_size = s.st_size;
    }
  else
    {
      char *err = strerror (errno);
      if (!err)
	err = "(unknown error)";
      note (IDS_ERR_OPEN_READ, path, err);
    }
}

NetIO_File::~NetIO_File ()
{
  if (fd)
    fclose ((FILE *)fd);
}

int
NetIO_File::ok ()
{
  return fd ? 1 : 0;
}

int
NetIO_File::read (char *buf, int nbytes)
{
  return fread (buf, 1, nbytes, (FILE *)fd);
}