This file is set.def, from which is created set.c.
It implements the "set" and "unset" builtins in Bash.
Copyright (C) 1987-2004 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 set.c
#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 "../flags.h"
#include "common.h"
#include "bashgetopt.h"
#if defined (READLINE)
# include "../input.h"
# include "../bashline.h"
# include <readline/readline.h>
#endif
#if defined (HISTORY)
# include "../bashhist.h"
#endif
extern int posixly_correct, ignoreeof, eof_encountered_limit;
#if defined (HISTORY)
extern int dont_save_function_defs;
#endif
#if defined (READLINE)
extern int no_line_editing;
#endif /* READLINE */
$BUILTIN set
$FUNCTION set_builtin
$SHORT_DOC set [--abefhkmnptuvxBCHP] [-o option] [arg ...]
-a Mark variables which are modified or created for export.
-b Notify of job termination immediately.
-e Exit immediately if a command exits with a non-zero status.
-f Disable file name generation (globbing).
-h Remember the location of commands as they are looked up.
-k All assignment arguments are placed in the environment for a
command, not just those that precede the command name.
-m Job control is enabled.
-n Read commands but do not execute them.
-o option-name
Set the variable corresponding to option-name:
allexport same as -a
braceexpand same as -B
#if defined (READLINE)
emacs use an emacs-style line editing interface
#endif /* READLINE */
errexit same as -e
errtrace same as -E
functrace same as -T
hashall same as -h
#if defined (BANG_HISTORY)
histexpand same as -H
#endif /* BANG_HISTORY */
#if defined (HISTORY)
history enable command history
#endif
ignoreeof the shell will not exit upon reading EOF
interactive-comments
allow comments to appear in interactive commands
keyword same as -k
monitor same as -m
noclobber same as -C
noexec same as -n
noglob same as -f
nolog currently accepted but ignored
notify same as -b
nounset same as -u
onecmd same as -t
physical same as -P
pipefail the return value of a pipeline is the status of
the last command to exit with a non-zero status,
or zero if no command exited with a non-zero status
posix change the behavior of bash where the default
operation differs from the 1003.2 standard to
match the standard
privileged same as -p
verbose same as -v
#if defined (READLINE)
vi use a vi-style line editing interface
#endif /* READLINE */
xtrace same as -x
-p Turned on whenever the real and effective user ids do not match.
Disables processing of the $ENV file and importing of shell
functions. Turning this option off causes the effective uid and
gid to be set to the real uid and gid.
-t Exit after reading and executing one command.
-u Treat unset variables as an error when substituting.
-v Print shell input lines as they are read.
-x Print commands and their arguments as they are executed.
#if defined (BRACE_EXPANSION)
-B the shell will perform brace expansion
#endif /* BRACE_EXPANSION */
-C If set, disallow existing regular files to be overwritten
by redirection of output.
-E If set, the ERR trap is inherited by shell functions.
#if defined (BANG_HISTORY)
-H Enable ! style history substitution. This flag is on
by default when the shell is interactive.
#endif /* BANG_HISTORY */
-P If set, do not follow symbolic links when executing commands
such as cd which change the current directory.
-T If set, the DEBUG trap is inherited by shell functions.
- Assign any remaining arguments to the positional parameters.
The -x and -v options are turned off.
Using + rather than - causes these flags to be turned off. The
flags can also be used upon invocation of the shell. The current
set of flags may be found in $-. The remaining n ARGs are positional
parameters and are assigned, in order, to $1, $2, .. $n. If no
ARGs are given, all shell variables are printed.
$END
typedef int setopt_set_func_t __P((int, char *));
typedef int setopt_get_func_t __P((char *));
static void print_minus_o_option __P((char *, int, int));
static void print_all_shell_variables __P((void));
static int set_ignoreeof __P((int, char *));
static int set_posix_mode __P((int, char *));
#if defined (READLINE)
static int set_edit_mode __P((int, char *));
static int get_edit_mode __P((char *));
#endif
#if defined (HISTORY)
static int bash_set_history __P((int, char *));
#endif
static char *on = "on";
static char *off = "off";
/* A struct used to match long options for set -o to the corresponding
option letter or internal variable. The functions can be called to
dynamically generate values. */
struct {
char *name;
int letter;
int *variable;
setopt_set_func_t *set_func;
setopt_get_func_t *get_func;
} o_options[] = {
{ "allexport", 'a', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL },
#if defined (BRACE_EXPANSION)
{ "braceexpand",'B', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL },
#endif
#if defined (READLINE)
{ "emacs", '\0', (int *)NULL, set_edit_mode, get_edit_mode },
#endif
{ "errexit", 'e', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL },
{ "errtrace", 'E', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL },
{ "functrace", 'T', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL },
{ "hashall", 'h', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL },
#if defined (BANG_HISTORY)
{ "histexpand", 'H', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL },
#endif /* BANG_HISTORY */
#if defined (HISTORY)
{ "history", '\0', &remember_on_history, bash_set_history, (setopt_get_func_t *)NULL },
#endif
{ "ignoreeof", '\0', &ignoreeof, set_ignoreeof, (setopt_get_func_t *)NULL },
{ "interactive-comments", '\0', &interactive_comments, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL },
{ "keyword", 'k', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL },
{ "monitor", 'm', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL },
{ "noclobber", 'C', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL },
{ "noexec", 'n', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL },
{ "noglob", 'f', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL },
#if defined (HISTORY)
{ "nolog", '\0', &dont_save_function_defs, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL },
#endif
#if defined (JOB_CONTROL)
{ "notify", 'b', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL },
#endif /* JOB_CONTROL */
{ "nounset", 'u', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL },
{ "onecmd", 't', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL },
{ "physical", 'P', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL },
{ "pipefail", '\0', &pipefail_opt, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL },
{ "posix", '\0', &posixly_correct, set_posix_mode, (setopt_get_func_t *)NULL },
{ "privileged", 'p', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL },
{ "verbose", 'v', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL },
#if defined (READLINE)
{ "vi", '\0', (int *)NULL, set_edit_mode, get_edit_mode },
#endif
{ "xtrace", 'x', (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL },
{(char *)NULL, 0 , (int *)NULL, (setopt_set_func_t *)NULL, (setopt_get_func_t *)NULL },
};
#define N_O_OPTIONS (sizeof (o_options) / sizeof (o_options[0]))
#define GET_BINARY_O_OPTION_VALUE(i, name) \
((o_options[i].get_func) ? (*o_options[i].get_func) (name) \
: (*o_options[i].variable))
#define SET_BINARY_O_OPTION_VALUE(i, onoff, name) \
((o_options[i].set_func) ? (*o_options[i].set_func) (onoff, name) \
: (*o_options[i].variable = (onoff == FLAG_ON)))
int
minus_o_option_value (name)
char *name;
{
register int i;
int *on_or_off;
for (i = 0; o_options[i].name; i++)
{
if (STREQ (name, o_options[i].name))
{
if (o_options[i].letter)
{
on_or_off = find_flag (o_options[i].letter);
return ((on_or_off == FLAG_UNKNOWN) ? -1 : *on_or_off);
}
else
return (GET_BINARY_O_OPTION_VALUE (i, name));
}
}
return (-1);
}
#define MINUS_O_FORMAT "%-15s\t%s\n"
static void
print_minus_o_option (name, value, pflag)
char *name;
int value, pflag;
{
if (pflag == 0)
printf (MINUS_O_FORMAT, name, value ? on : off);
else
printf ("set %co %s\n", value ? '-' : '+', name);
}
void
list_minus_o_opts (mode, reusable)
int mode, reusable;
{
register int i;
int *on_or_off, value;
for (i = 0; o_options[i].name; i++)
{
if (o_options[i].letter)
{
value = 0;
on_or_off = find_flag (o_options[i].letter);
if (on_or_off == FLAG_UNKNOWN)
on_or_off = &value;
if (mode == -1 || mode == *on_or_off)
print_minus_o_option (o_options[i].name, *on_or_off, reusable);
}
else
{
value = GET_BINARY_O_OPTION_VALUE (i, o_options[i].name);
if (mode == -1 || mode == value)
print_minus_o_option (o_options[i].name, value, reusable);
}
}
}
char **
get_minus_o_opts ()
{
char **ret;
int i;
ret = strvec_create (N_O_OPTIONS + 1);
for (i = 0; o_options[i].name; i++)
ret[i] = o_options[i].name;
ret[i] = (char *)NULL;
return ret;
}
static int
set_ignoreeof (on_or_off, option_name)
int on_or_off;
char *option_name;
{
ignoreeof = on_or_off == FLAG_ON;
unbind_variable ("ignoreeof");
if (ignoreeof)
bind_variable ("IGNOREEOF", "10", 0);
else
unbind_variable ("IGNOREEOF");
sv_ignoreeof ("IGNOREEOF");
return 0;
}
static int
set_posix_mode (on_or_off, option_name)
int on_or_off;
char *option_name;
{
posixly_correct = on_or_off == FLAG_ON;
if (posixly_correct == 0)
unbind_variable ("POSIXLY_CORRECT");
else
bind_variable ("POSIXLY_CORRECT", "y", 0);
sv_strict_posix ("POSIXLY_CORRECT");
return (0);
}
#if defined (READLINE)
/* Magic. This code `knows' how readline handles rl_editing_mode. */
static int
set_edit_mode (on_or_off, option_name)
int on_or_off;
char *option_name;
{
int isemacs;
if (on_or_off == FLAG_ON)
{
rl_variable_bind ("editing-mode", option_name);
if (interactive)
with_input_from_stdin ();
no_line_editing = 0;
}
else
{
isemacs = rl_editing_mode == 1;
if ((isemacs && *option_name == 'e') || (!isemacs && *option_name == 'v'))
{
if (interactive)
with_input_from_stream (stdin, "stdin");
no_line_editing = 1;
}
}
return 1-no_line_editing;
}
static int
get_edit_mode (name)
char *name;
{
return (*name == 'e' ? no_line_editing == 0 && rl_editing_mode == 1
: no_line_editing == 0 && rl_editing_mode == 0);
}
#endif /* READLINE */
#if defined (HISTORY)
static int
bash_set_history (on_or_off, option_name)
int on_or_off;
char *option_name;
{
if (on_or_off == FLAG_ON)
{
bash_history_enable ();
if (history_lines_this_session == 0)
load_history ();
}
else
bash_history_disable ();
return (1 - remember_on_history);
}
#endif
int
set_minus_o_option (on_or_off, option_name)
int on_or_off;
char *option_name;
{
register int i;
for (i = 0; o_options[i].name; i++)
{
if (STREQ (option_name, o_options[i].name))
{
if (o_options[i].letter == 0)
{
SET_BINARY_O_OPTION_VALUE (i, on_or_off, option_name);
return (EXECUTION_SUCCESS);
}
else
{
if (change_flag (o_options[i].letter, on_or_off) == FLAG_ERROR)
{
sh_invalidoptname (option_name);
return (EXECUTION_FAILURE);
}
else
return (EXECUTION_SUCCESS);
}
}
}
sh_invalidoptname (option_name);
return (EXECUTION_FAILURE);
}
static void
print_all_shell_variables ()
{
SHELL_VAR **vars;
vars = all_shell_variables ();
if (vars)
{
print_var_list (vars);
free (vars);
}
/* POSIX.2 does not allow function names and definitions to be output when
`set' is invoked without options (PASC Interp #202). */
if (posixly_correct == 0)
{
vars = all_shell_functions ();
if (vars)
{
print_func_list (vars);
free (vars);
}
}
}
void
set_shellopts ()
{
char *value;
char tflag[N_O_OPTIONS];
int vsize, i, vptr, *ip, exported;
SHELL_VAR *v;
for (vsize = i = 0; o_options[i].name; i++)
{
tflag[i] = 0;
if (o_options[i].letter)
{
ip = find_flag (o_options[i].letter);
if (ip && *ip)
{
vsize += strlen (o_options[i].name) + 1;
tflag[i] = 1;
}
}
else if (GET_BINARY_O_OPTION_VALUE (i, o_options[i].name))
{
vsize += strlen (o_options[i].name) + 1;
tflag[i] = 1;
}
}
value = (char *)xmalloc (vsize + 1);
for (i = vptr = 0; o_options[i].name; i++)
{
if (tflag[i])
{
strcpy (value + vptr, o_options[i].name);
vptr += strlen (o_options[i].name);
value[vptr++] = ':';
}
}
if (vptr)
vptr--; /* cut off trailing colon */
value[vptr] = '\0';
v = find_variable ("SHELLOPTS");
/* Turn off the read-only attribute so we can bind the new value, and
note whether or not the variable was exported. */
if (v)
{
VUNSETATTR (v, att_readonly);
exported = exported_p (v);
}
else
exported = 0;
v = bind_variable ("SHELLOPTS", value, 0);
/* Turn the read-only attribute back on, and turn off the export attribute
if it was set implicitly by mark_modified_vars and SHELLOPTS was not
exported before we bound the new value. */
VSETATTR (v, att_readonly);
if (mark_modified_vars && exported == 0 && exported_p (v))
VUNSETATTR (v, att_exported);
free (value);
}
void
parse_shellopts (value)
char *value;
{
char *vname;
int vptr;
vptr = 0;
while (vname = extract_colon_unit (value, &vptr))
{
set_minus_o_option (FLAG_ON, vname);
free (vname);
}
}
void
initialize_shell_options (no_shellopts)
int no_shellopts;
{
char *temp;
SHELL_VAR *var;
if (no_shellopts == 0)
{
var = find_variable ("SHELLOPTS");
/* set up any shell options we may have inherited. */
if (var && imported_p (var))
{
temp = (array_p (var)) ? (char *)NULL : savestring (value_cell (var));
if (temp)
{
parse_shellopts (temp);
free (temp);
}
}
}
/* Set up the $SHELLOPTS variable. */
set_shellopts ();
}
/* Reset the values of the -o options that are not also shell flags. This is
called from execute_cmd.c:initialize_subshell() when setting up a subshell
to run an executable shell script without a leading `#!'. */
void
reset_shell_options ()
{
#if defined (HISTORY)
remember_on_history = 1;
#endif
ignoreeof = 0;
}
/* Set some flags from the word values in the input list. If LIST is empty,
then print out the values of the variables instead. If LIST contains
non-flags, then set $1 - $9 to the successive words of LIST. */
int
set_builtin (list)
WORD_LIST *list;
{
int on_or_off, flag_name, force_assignment, opts_changed;
register char *arg;
char s[3];
if (list == 0)
{
print_all_shell_variables ();
return (EXECUTION_SUCCESS);
}
/* Check validity of flag arguments. */
reset_internal_getopt ();
while ((flag_name = internal_getopt (list, optflags)) != -1)
{
switch (flag_name)
{
case '?':
builtin_usage ();
return (list_optopt == '?' ? EXECUTION_SUCCESS : EX_USAGE);
default:
break;
}
}
/* Do the set command. While the list consists of words starting with
'-' or '+' treat them as flags, otherwise, start assigning them to
$1 ... $n. */
for (force_assignment = opts_changed = 0; list; )
{
arg = list->word->word;
/* If the argument is `--' or `-' then signal the end of the list
and remember the remaining arguments. */
if (arg[0] == '-' && (!arg[1] || (arg[1] == '-' && !arg[2])))
{
list = list->next;
/* `set --' unsets the positional parameters. */
if (arg[1] == '-')
force_assignment = 1;
/* Until told differently, the old shell behaviour of
`set - [arg ...]' being equivalent to `set +xv [arg ...]'
stands. Posix.2 says the behaviour is marked as obsolescent. */
else
{
change_flag ('x', '+');
change_flag ('v', '+');
opts_changed = 1;
}
break;
}
if ((on_or_off = *arg) && (on_or_off == '-' || on_or_off == '+'))
{
while (flag_name = *++arg)
{
if (flag_name == '?')
{
builtin_usage ();
return (EXECUTION_SUCCESS);
}
else if (flag_name == 'o') /* -+o option-name */
{
char *option_name;
WORD_LIST *opt;
opt = list->next;
if (opt == 0)
{
list_minus_o_opts (-1, (on_or_off == '+'));
continue;
}
option_name = opt->word->word;
if (option_name == 0 || *option_name == '\0' ||
*option_name == '-' || *option_name == '+')
{
list_minus_o_opts (-1, (on_or_off == '+'));
continue;
}
list = list->next; /* Skip over option name. */
opts_changed = 1;
if (set_minus_o_option (on_or_off, option_name) != EXECUTION_SUCCESS)
{
set_shellopts ();
return (EXECUTION_FAILURE);
}
}
else if (change_flag (flag_name, on_or_off) == FLAG_ERROR)
{
s[0] = on_or_off;
s[1] = flag_name;
s[2] = '\0';
sh_invalidopt (s);
builtin_usage ();
set_shellopts ();
return (EXECUTION_FAILURE);
}
opts_changed = 1;
}
}
else
{
break;
}
list = list->next;
}
/* Assigning $1 ... $n */
if (list || force_assignment)
remember_args (list, 1);
/* Set up new value of $SHELLOPTS */
if (opts_changed)
set_shellopts ();
return (EXECUTION_SUCCESS);
}
$BUILTIN unset
$FUNCTION unset_builtin
$SHORT_DOC unset [-f] [-v] [name ...]
For each NAME, remove the corresponding variable or function. Given
the `-v', unset will only act on variables. Given the `-f' flag,
unset will only act on functions. With neither flag, unset first
tries to unset a variable, and if that fails, then tries to unset a
function. Some variables cannot be unset; also see readonly.
$END
#define NEXT_VARIABLE() any_failed++; list = list->next; continue;
int
unset_builtin (list)
WORD_LIST *list;
{
int unset_function, unset_variable, unset_array, opt, any_failed;
char *name;
unset_function = unset_variable = unset_array = any_failed = 0;
reset_internal_getopt ();
while ((opt = internal_getopt (list, "fv")) != -1)
{
switch (opt)
{
case 'f':
unset_function = 1;
break;
case 'v':
unset_variable = 1;
break;
default:
builtin_usage ();
return (EX_USAGE);
}
}
list = loptend;
if (unset_function && unset_variable)
{
builtin_error (_("cannot simultaneously unset a function and a variable"));
return (EXECUTION_FAILURE);
}
while (list)
{
SHELL_VAR *var;
int tem;
#if defined (ARRAY_VARS)
char *t;
#endif
name = list->word->word;
#if defined (ARRAY_VARS)
unset_array = 0;
if (!unset_function && valid_array_reference (name))
{
t = strchr (name, '[');
*t++ = '\0';
unset_array++;
}
#endif
/* Bash allows functions with names which are not valid identifiers
to be created when not in posix mode, so check only when in posix
mode when unsetting a function. */
if (((unset_function && posixly_correct) || !unset_function) && legal_identifier (name) == 0)
{
sh_invalidid (name);
NEXT_VARIABLE ();
}
var = unset_function ? find_function (name) : find_variable (name);
if (var && !unset_function && non_unsettable_p (var))
{
builtin_error (_("%s: cannot unset"), name);
NEXT_VARIABLE ();
}
/* Posix.2 says that unsetting readonly variables is an error. */
if (var && readonly_p (var))
{
builtin_error (_("%s: cannot unset: readonly %s"),
name, unset_function ? "function" : "variable");
NEXT_VARIABLE ();
}
/* Unless the -f option is supplied, the name refers to a variable. */
#if defined (ARRAY_VARS)
if (var && unset_array)
{
if (array_p (var) == 0)
{
builtin_error (_("%s: not an array variable"), name);
NEXT_VARIABLE ();
}
else
{
tem = unbind_array_element (var, t);
if (tem == -1)
any_failed++;
}
}
else
#endif /* ARRAY_VARS */
tem = unset_function ? unbind_func (name) : unbind_variable (name);
/* This is what Posix.2 draft 11+ says. ``If neither -f nor -v
is specified, the name refers to a variable; if a variable by
that name does not exist, a function by that name, if any,
shall be unset.'' */
if (tem == -1 && !unset_function && !unset_variable)
tem = unbind_func (name);
/* SUSv3, POSIX.1-2001 say: ``Unsetting a variable or function that
was not previously set shall not be considered an error.'' */
if (unset_function == 0)
stupidly_hack_special_variables (name);
list = list->next;
}
return (any_failed ? EXECUTION_FAILURE : EXECUTION_SUCCESS);
}