builtins/alias.def

This file is alias.def, from which is created alias.c
It implements the builtins "alias" and "unalias" in Bash.

Copyright (C) 1987, 1989, 1991 Free Software Foundation, Inc.

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

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$BUILTIN alias
$FUNCTION alias_builtin
$DEPENDS_ON ALIAS
$PRODUCES alias.c
$SHORT_DOC alias [-p] [name[=value] ... ]
`alias' with no arguments or with the -p option prints the list
of aliases in the form alias NAME=VALUE on standard output.
Otherwise, an alias is defined for each NAME whose VALUE is given.
A trailing space in VALUE causes the next word to be checked for
alias substitution when the alias is expanded.  Alias returns
true unless a NAME is given for which no alias has been defined.
$END

#include <config.h>

#if defined (ALIAS)

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

#  include "../bashansi.h"

#  include <stdio.h>
#  include "../shell.h"
#  include "../alias.h"
#  include "common.h"
#  include "bashgetopt.h"

static void print_alias __P((alias_t *));

/* Hack the alias command in a Korn shell way. */
int
alias_builtin (list)
     WORD_LIST *list;
{
  int any_failed, offset, pflag;
  alias_t **alias_list, *t;
  char *name, *value;

  pflag = 0;
  reset_internal_getopt ();
  while ((offset = internal_getopt (list, "p")) != -1)
    {
      switch (offset)
	{
	case 'p':
	  pflag = 1;
	  break;
	default:
	  builtin_usage ();
	  return (EX_USAGE);
	}
    }

  list = loptend;

  if (list == 0 || pflag)
    {
      if (aliases == 0)
	return (EXECUTION_SUCCESS);

      alias_list = all_aliases ();

      if (alias_list == 0)
	return (EXECUTION_SUCCESS);

      for (offset = 0; alias_list[offset]; offset++)
	print_alias (alias_list[offset]);

      free (alias_list);	/* XXX - Do not free the strings. */

      if (list == 0)
	return (EXECUTION_SUCCESS);
    }

  any_failed = 0;
  while (list)
    {
      name = list->word->word;

      for (offset = 0; name[offset] && name[offset] != '='; offset++)
	;

      if (offset && name[offset] == '=')
	{
	  name[offset] = '\0';
	  value = name + offset + 1;

	  add_alias (name, value);
	}
      else
	{
	  t = find_alias (name);
	  if (t)
	    print_alias (t);
	  else
	    {
	      builtin_error ("`%s' not found", name);
	      any_failed++;
	    }
	}
      list = list->next;
    }

  return (any_failed ? EXECUTION_FAILURE : EXECUTION_SUCCESS);
}
#endif /* ALIAS */

$BUILTIN unalias
$FUNCTION unalias_builtin
$DEPENDS_ON ALIAS
$SHORT_DOC unalias [-a] [name ...]
Remove NAMEs from the list of defined aliases.  If the -a option is given,
then remove all alias definitions.
$END

#if defined (ALIAS)
/* Remove aliases named in LIST from the aliases database. */
int
unalias_builtin (list)
     register WORD_LIST *list;
{
  register alias_t *alias;
  int opt, aflag;

  aflag = 0;
  reset_internal_getopt ();
  while ((opt = internal_getopt (list, "a")) != -1)
    {
      switch (opt)
	{
	case 'a':
	  aflag = 1;
	  break;
	default:
	  builtin_usage ();
	  return (EX_USAGE);
	}
    }

  list = loptend;

  if (aflag)
    {
      delete_all_aliases ();
      return (EXECUTION_SUCCESS);
    }

  aflag = 0;
  while (list)
    {
      alias = find_alias (list->word->word);

      if (alias)
	remove_alias (alias->name);
      else
	{
	  builtin_error ("`%s': not an alias", list->word->word);
	  aflag++;
	}

      list = list->next;
    }

  return (aflag ? EXECUTION_FAILURE : EXECUTION_SUCCESS);
}

/* Output ALIAS in such a way as to allow it to be read back in. */
static void
print_alias (alias)
     alias_t *alias;
{
  char *value;

  value = sh_single_quote (alias->value);
  printf ("alias %s=%s\n", alias->name, value);
  free (value);

  fflush (stdout);
}
#endif /* ALIAS */