This file is trap.def, from which is created trap.c.
It implements the builtin "trap" in Bash.
-Copyright (C) 1987, 1989, 1991 Free Software Foundation, Inc.
+Copyright (C) 1987-2009 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 1, or (at your option) any later
-version.
+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 3 of the License, 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.
+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, 675 Mass Ave, Cambridge, MA 02139, USA.
+You should have received a copy of the GNU General Public License
+along with Bash. If not, see <http://www.gnu.org/licenses/>.
$PRODUCES trap.c
$BUILTIN trap
$FUNCTION trap_builtin
-$SHORT_DOC trap [arg] [signal_spec ...] or trap -l
-The command ARG is to be read and executed when the shell receives
-signal(s) SIGNAL_SPEC. If ARG is absent all specified signals are
-reset to their original values. If ARG is the null string each
-SIGNAL_SPEC is ignored by the shell and by the commands it invokes.
-If a SIGNAL_SPEC is EXIT (0) the command ARG is executed on exit from
-the shell. If a SIGNAL_SPEC is DEBUG, ARG is executed after every
-command. If ARG is `-p' then the trap commands associated with
-each SIGNAL_SPEC are displayed. If no arguments are supplied or if
-only `-p' is given, trap prints the list of commands associated with
-each signal number. Each SIGNAL_SPEC is either a signal name in <signal.h>
-or a signal number. `trap -l' prints a list of signal names and their
-corresponding numbers. Note that a signal can be sent to the shell
-with "kill -signal $$".
+$SHORT_DOC trap [-lp] [[arg] signal_spec ...]
+Trap signals and other events.
+
+Defines and activates handlers to be run when the shell receives signals
+or other conditions.
+
+ARG is a command to be read and executed when the shell receives the
+signal(s) SIGNAL_SPEC. If ARG is absent (and a single SIGNAL_SPEC
+is supplied) or `-', each specified signal is reset to its original
+value. If ARG is the null string each SIGNAL_SPEC is ignored by the
+shell and by the commands it invokes.
+
+If a SIGNAL_SPEC is EXIT (0) ARG is executed on exit from the shell. If
+a SIGNAL_SPEC is DEBUG, ARG is executed before every simple command.
+
+If no arguments are supplied, trap prints the list of commands associated
+with each signal.
+
+Options:
+ -l print a list of signal names and their corresponding numbers
+ -p display the trap commands associated with each SIGNAL_SPEC
+
+Each SIGNAL_SPEC is either a signal name in <signal.h> or a signal number.
+Signal names are case insensitive and the SIG prefix is optional. A
+signal may be sent to the shell with "kill -signal $$".
+
+Exit Status:
+Returns success unless a SIGSPEC is invalid or an invalid option is given.
$END
#include <config.h>
#if defined (HAVE_UNISTD_H)
+# ifdef _MINIX
+# include <sys/types.h>
+# endif
# include <unistd.h>
#endif
#include "common.h"
#include "bashgetopt.h"
-static int display_traps ();
+static void showtrap __P((int));
+static int display_traps __P((WORD_LIST *));
/* The trap command:
#define REVERT 1 /* Revert to this signals original value. */
#define IGNORE 2 /* Ignore this signal. */
-extern int interactive;
+extern int posixly_correct;
int
trap_builtin (list)
}
list = loptend;
+ opt = DSIG_NOCASE|DSIG_SIGPREFIX; /* flags for decode_signal */
+
if (list_signal_names)
- return (display_signal_list ((WORD_LIST *)NULL, 1));
+ return (sh_chkwrite (display_signal_list ((WORD_LIST *)NULL, 1)));
else if (display || list == 0)
- return (display_traps (list));
+ return (sh_chkwrite (display_traps (list)));
else
{
char *first_arg;
- int operation, sig;
+ int operation, sig, first_signal;
operation = SET;
first_arg = list->word->word;
- if (first_arg && *first_arg && (*first_arg != '-' || first_arg[1]) &&
- signal_object_p (first_arg))
+ first_signal = first_arg && *first_arg && all_digits (first_arg) && signal_object_p (first_arg, opt);
+
+ /* Backwards compatibility. XXX - question about whether or not we
+ should throw an error if an all-digit argument doesn't correspond
+ to a valid signal number (e.g., if it's `50' on a system with only
+ 32 signals). */
+ if (first_signal)
+ operation = REVERT;
+ /* When in posix mode, the historical behavior of looking for a
+ missing first argument is disabled. To revert to the original
+ signal handling disposition, use `-' as the first argument. */
+ else if (posixly_correct == 0 && first_arg && *first_arg &&
+ (*first_arg != '-' || first_arg[1]) &&
+ signal_object_p (first_arg, opt) && list->next == 0)
operation = REVERT;
else
{
list = list->next;
- if (*first_arg == '\0')
+ if (list == 0)
+ {
+ builtin_usage ();
+ return (EX_USAGE);
+ }
+ else if (*first_arg == '\0')
operation = IGNORE;
else if (first_arg[0] == '-' && !first_arg[1])
operation = REVERT;
while (list)
{
- sig = decode_signal (list->word->word);
+ sig = decode_signal (list->word->word, opt);
if (sig == NO_SIG)
{
- builtin_error ("%s: not a signal specification",
- list->word->word);
+ sh_invalidsig (list->word->word);
result = EXECUTION_FAILURE;
}
else
if (interactive)
set_signal_handler (SIGINT, sigint_sighandler);
else
- set_signal_handler (SIGINT, termination_unwind_protect);
+ set_signal_handler (SIGINT, termsig_sighandler);
break;
case SIGQUIT:
char *t, *p, *sn;
p = trap_list[i];
-
if (p == (char *)DEFAULT_SIG)
return;
- t = (p == (char *)IGNORE_SIG) ? (char *)NULL : single_quote (p);
+ t = (p == (char *)IGNORE_SIG) ? (char *)NULL : sh_single_quote (p);
sn = signal_name (i);
/* Make sure that signals whose names are unknown (for whatever reason)
are printed as signal numbers. */
if (STREQN (sn, "SIGJUNK", 7) || STREQN (sn, "unknown", 7))
printf ("trap -- %s %d\n", t ? t : "''", i);
+ else if (posixly_correct)
+ {
+ if (STREQN (sn, "SIG", 3))
+ printf ("trap -- %s %s\n", t ? t : "''", sn+3);
+ else
+ printf ("trap -- %s %s\n", t ? t : "''", sn);
+ }
else
printf ("trap -- %s %s\n", t ? t : "''", sn);
if (list == 0)
{
- for (i = 0; i <= NSIG; i++)
+ for (i = 0; i < BASH_NSIG; i++)
showtrap (i);
return (EXECUTION_SUCCESS);
}
for (result = EXECUTION_SUCCESS; list; list = list->next)
{
- i = decode_signal (list->word->word);
+ i = decode_signal (list->word->word, DSIG_NOCASE|DSIG_SIGPREFIX);
if (i == NO_SIG)
{
+ sh_invalidsig (list->word->word);
result = EXECUTION_FAILURE;
- builtin_error ("%s: not a signal specification", list->word->word);
}
else
showtrap (i);