source: trunk/essentials/app-shells/bash/builtins/enable.def@ 3951

This file is enable.def, from which is created enable.c.
It implements the builtin "enable" in Bash.

Copyright (C) 1987-2003 Free Software Foundation, Inc.

This file is part of GNU Bash, the Bourne Again SHell.

Bash 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.

Bash 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 Bash; see the file COPYING.  If not, write to the Free Software
Foundation, 59 Temple Place, Suite 330, Boston, MA 02111 USA.

$PRODUCES enable.c

$BUILTIN enable
$FUNCTION enable_builtin
$SHORT_DOC enable [-pnds] [-a] [-f filename] [name ...]
Enable and disable builtin shell commands.  This allows
you to use a disk command which has the same name as a shell
builtin without specifying a full pathname.  If -n is used, the
NAMEs become disabled; otherwise NAMEs are enabled.  For example,
to use the `test' found in $PATH instead of the shell builtin
version, type `enable -n test'.  On systems supporting dynamic
loading, the -f option may be used to load new builtins from the
shared object FILENAME.  The -d option will delete a builtin
previously loaded with -f.  If no non-option names are given, or
the -p option is supplied, a list of builtins is printed.  The
-a option means to print every builtin with an indication of whether
or not it is enabled.  The -s option restricts the output to the POSIX.2
`special' builtins.  The -n option displays a list of all disabled builtins.
$END

#include <config.h>

#if defined (HAVE_UNISTD_H)
#  ifdef _MINIX
#    include <sys/types.h>
#  endif
#  include <unistd.h>
#endif

#include <stdio.h>
#include "../bashansi.h"
#include "../bashintl.h"

#include "../shell.h"
#include "../builtins.h"
#include "../flags.h"
#include "common.h"
#include "bashgetopt.h"

#if defined (PROGRAMMABLE_COMPLETION)
#  include "../pcomplete.h"
#endif

#define ENABLED  1
#define DISABLED 2
#define SPECIAL  4

#define AFLAG   0x01
#define DFLAG   0x02
#define FFLAG   0x04
#define NFLAG   0x08
#define PFLAG   0x10
#define SFLAG   0x20

#if defined (HAVE_DLOPEN) && defined (HAVE_DLSYM)
static int dyn_load_builtin __P((WORD_LIST *, int, char *));
#endif

#if defined (HAVE_DLCLOSE)
static int dyn_unload_builtin __P((char *));
static void delete_builtin __P((struct builtin *));
static int local_dlclose __P((void *));
#endif

static void list_some_builtins __P((int));
static int enable_shell_command __P((char *, int));

/* Enable/disable shell commands present in LIST.  If list is not specified,
   then print out a list of shell commands showing which are enabled and
   which are disabled. */
int
enable_builtin (list)
     WORD_LIST *list;
{
  int result, flags;
  int opt, filter;
#if defined (HAVE_DLOPEN) && defined (HAVE_DLSYM)
  char *filename;
#endif

  result = EXECUTION_SUCCESS;
  flags = 0;

  reset_internal_getopt ();
  while ((opt = internal_getopt (list, "adnpsf:")) != -1)
    {
      switch (opt)
        {
        case 'a':
          flags |= AFLAG;
          break;
        case 'n':
          flags |= NFLAG;
          break;
        case 'p':
          flags |= PFLAG;
          break;
        case 's':
          flags |= SFLAG;
          break;
        case 'f':
#if defined (HAVE_DLOPEN) && defined (HAVE_DLSYM)
          flags |= FFLAG;
          filename = list_optarg;
          break;
#else
          builtin_error (_("dynamic loading not available"));
          return (EX_USAGE);
#endif
#if defined (HAVE_DLCLOSE)
        case 'd':
          flags |= DFLAG;
          break;
#else
          builtin_error (_("dynamic loading not available"));
          return (EX_USAGE);
#endif /* HAVE_DLCLOSE */
        default:
          builtin_usage ();
          return (EX_USAGE);
        }
    }

  list = loptend;

#if defined (RESTRICTED_SHELL)
  /* Restricted shells cannot load new builtins. */
  if (restricted && (flags & (FFLAG|DFLAG)))
    {
      sh_restricted ((char *)NULL);
      return (EXECUTION_FAILURE);
    }
#endif

  if (list == 0 || (flags & PFLAG))
    {
      filter = (flags & AFLAG) ? (ENABLED | DISABLED)
                               : (flags & NFLAG) ? DISABLED : ENABLED;