/* trap.c -- Not the trap command, but useful functions for manipulating
those objects. The trap command is in builtins/trap.def. */
-/* Copyright (C) 1987-2005 Free Software Foundation, Inc.
+/* Copyright (C) 1987-2010 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 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, 59 Temple Place, Suite 330, Boston, MA 02111 USA. */
+ You should have received a copy of the GNU General Public License
+ along with Bash. If not, see <http://www.gnu.org/licenses/>.
+*/
#include "config.h"
#include "shell.h"
#include "flags.h"
#include "input.h" /* for save_token_state, restore_token_state */
+#include "jobs.h"
#include "signames.h"
#include "builtins.h"
#include "builtins/common.h"
static int _run_trap_internal __P((int, char *));
+static void free_trap_string __P((int));
static void reset_signal __P((int));
static void restore_signal __P((int));
static void reset_or_restore_signal_handlers __P((sh_resetsig_func_t *));
/* Variables used here but defined in other files. */
-extern int interrupt_immediately;
extern int last_command_exit_value;
extern int line_number;
extern procenv_t wait_intr_buf;
extern int return_catch_flag, return_catch_value;
extern int subshell_level;
+extern WORD_LIST *subst_assign_varlist;
/* The list of things to do originally, before we started trapping. */
SigHandler *original_signals[NSIG];
/* The (trapped) signal received while executing in the `wait' builtin */
int wait_signal_received;
-/* A value which can never be the target of a trap handler. */
-#define IMPOSSIBLE_TRAP_HANDLER (SigHandler *)initialize_traps
+#define GETORIGSIG(sig) \
+ do { \
+ original_signals[sig] = (SigHandler *)set_signal_handler (sig, SIG_DFL); \
+ set_signal_handler (sig, original_signals[sig]); \
+ if (original_signals[sig] == SIG_IGN) \
+ sigmodes[sig] |= SIG_HARD_IGNORE; \
+ } while (0)
+
+#define SETORIGSIG(sig,handler) \
+ do { \
+ original_signals[sig] = handler; \
+ if (original_signals[sig] == SIG_IGN) \
+ sigmodes[sig] |= SIG_HARD_IGNORE; \
+ } while (0)
+
+#define GET_ORIGINAL_SIGNAL(sig) \
+ if (sig && sig < NSIG && original_signals[sig] == IMPOSSIBLE_TRAP_HANDLER) \
+ GETORIGSIG(sig)
void
initialize_traps ()
{
register int i;
+ initialize_signames();
+
trap_list[EXIT_TRAP] = trap_list[DEBUG_TRAP] = trap_list[ERROR_TRAP] = trap_list[RETURN_TRAP] = (char *)NULL;
sigmodes[EXIT_TRAP] = sigmodes[DEBUG_TRAP] = sigmodes[ERROR_TRAP] = sigmodes[RETURN_TRAP] = SIG_INHERITED;
original_signals[EXIT_TRAP] = IMPOSSIBLE_TRAP_HANDLER;
{
pending_traps[i] = 0;
trap_list[i] = (char *)DEFAULT_SIG;
- sigmodes[i] = SIG_INHERITED;
+ sigmodes[i] = SIG_INHERITED; /* XXX - only set, not used */
original_signals[i] = IMPOSSIBLE_TRAP_HANDLER;
}
/* Show which signals are treated specially by the shell. */
#if defined (SIGCHLD)
- original_signals[SIGCHLD] =
- (SigHandler *) set_signal_handler (SIGCHLD, SIG_DFL);
- set_signal_handler (SIGCHLD, original_signals[SIGCHLD]);
+ GETORIGSIG (SIGCHLD);
sigmodes[SIGCHLD] |= (SIG_SPECIAL | SIG_NO_TRAP);
#endif /* SIGCHLD */
- original_signals[SIGINT] =
- (SigHandler *) set_signal_handler (SIGINT, SIG_DFL);
- set_signal_handler (SIGINT, original_signals[SIGINT]);
+ GETORIGSIG (SIGINT);
sigmodes[SIGINT] |= SIG_SPECIAL;
#if defined (__BEOS__)
/* BeOS sets SIGINT to SIG_IGN! */
original_signals[SIGINT] = SIG_DFL;
+ sigmodes[SIGINT] &= ~SIG_HARD_IGNORE;
#endif
- original_signals[SIGQUIT] =
- (SigHandler *) set_signal_handler (SIGQUIT, SIG_DFL);
- set_signal_handler (SIGQUIT, original_signals[SIGQUIT]);
+ GETORIGSIG (SIGQUIT);
sigmodes[SIGQUIT] |= SIG_SPECIAL;
if (interactive)
{
- original_signals[SIGTERM] =
- (SigHandler *)set_signal_handler (SIGTERM, SIG_DFL);
- set_signal_handler (SIGTERM, original_signals[SIGTERM]);
+ GETORIGSIG (SIGTERM);
sigmodes[SIGTERM] |= SIG_SPECIAL;
}
}
{
register int sig;
int old_exit_value, *token_state;
+ WORD_LIST *save_subst_varlist;
+#if defined (ARRAY_VARS)
+ ARRAY *ps;
+#endif
if (catch_flag == 0) /* simple optimization */
return;
/* Preserve $? when running trap. */
old_exit_value = last_command_exit_value;
+#if defined (ARRAY_VARS)
+ ps = save_pipestatus_array ();
+#endif
for (sig = 1; sig < NSIG; sig++)
{
run_interrupt_trap ();
CLRINTERRUPT;
}
+#if defined (JOB_CONTROL) && defined (SIGCHLD)
+ else if (sig == SIGCHLD &&
+ trap_list[SIGCHLD] != (char *)IMPOSSIBLE_TRAP_HANDLER &&
+ (sigmodes[SIGCHLD] & SIG_INPROGRESS) == 0)
+ {
+ run_sigchld_trap (pending_traps[sig]); /* use as counter */
+ }
+#endif
else if (trap_list[sig] == (char *)DEFAULT_SIG ||
trap_list[sig] == (char *)IGNORE_SIG ||
trap_list[sig] == (char *)IMPOSSIBLE_TRAP_HANDLER)
else
{
token_state = save_token_state ();
- parse_and_execute (savestring (trap_list[sig]), "trap", SEVAL_NONINT|SEVAL_NOHIST);
+ save_subst_varlist = subst_assign_varlist;
+ subst_assign_varlist = 0;
+
+ parse_and_execute (savestring (trap_list[sig]), "trap", SEVAL_NONINT|SEVAL_NOHIST|SEVAL_RESETLINE);
restore_token_state (token_state);
free (token_state);
+
+ subst_assign_varlist = save_subst_varlist;
}
pending_traps[sig] = 0;
}
}
+#if defined (ARRAY_VARS)
+ restore_pipestatus_array (ps);
+#endif
last_command_exit_value = old_exit_value;
}
{
int oerrno;
+ if ((sigmodes[sig] & SIG_TRAPPED) == 0)
+ {
+#if defined (DEBUG)
+ internal_warning ("trap_handler: signal %d: signal not trapped", sig);
+#endif
+ SIGRETURN (0);
+ }
+
if ((sig >= NSIG) ||
(trap_list[sig] == (char *)DEFAULT_SIG) ||
(trap_list[sig] == (char *)IGNORE_SIG))
{
oerrno = errno;
#if defined (MUST_REINSTALL_SIGHANDLERS)
+# if defined (JOB_CONTROL) && defined (SIGCHLD)
+ if (sig != SIGCHLD)
+# endif /* JOB_CONTROL && SIGCHLD */
set_signal_handler (sig, trap_handler);
#endif /* MUST_REINSTALL_SIGHANDLERS */
#endif
/* Make COMMAND_STRING be executed when SIGCHLD is caught iff SIGCHLD
- is not already trapped. */
+ is not already trapped. IMPOSSIBLE_TRAP_HANDLER is used as a sentinel
+ to make sure that a SIGCHLD trap handler run via run_sigchld_trap can
+ reset the disposition to the default and not have the original signal
+ accidentally restored, undoing the user's command. */
void
maybe_set_sigchld_trap (command_string)
char *command_string;
{
- if ((sigmodes[SIGCHLD] & SIG_TRAPPED) == 0)
+ if ((sigmodes[SIGCHLD] & SIG_TRAPPED) == 0 && trap_list[SIGCHLD] == (char *)IMPOSSIBLE_TRAP_HANDLER)
set_signal (SIGCHLD, command_string);
}
+
+/* Temporarily set the SIGCHLD trap string to IMPOSSIBLE_TRAP_HANDLER. Used
+ as a sentinel in run_sigchld_trap and maybe_set_sigchld_trap to see whether
+ or not a SIGCHLD trap handler reset SIGCHLD disposition to the default. */
+void
+set_impossible_sigchld_trap ()
+{
+ restore_default_signal (SIGCHLD);
+ change_signal (SIGCHLD, (char *)IMPOSSIBLE_TRAP_HANDLER);
+ sigmodes[SIGCHLD] &= ~SIG_TRAPPED; /* maybe_set_sigchld_trap checks this */
+}
#endif /* JOB_CONTROL && SIGCHLD */
void
else if (interactive) /* XXX - was interactive_shell */
return (set_signal_handler (SIGINT, sigint_sighandler));
else
- return (set_signal_handler (SIGINT, termination_unwind_protect));
+ return (set_signal_handler (SIGINT, termsig_sighandler));
}
/* Return the correct handler for signal SIG according to the values in
{
/* If we aren't sure of the original value, check it. */
if (original_signals[sig] == IMPOSSIBLE_TRAP_HANDLER)
- {
- original_signals[sig] = (SigHandler *)set_signal_handler (sig, SIG_DFL);
- set_signal_handler (sig, original_signals[sig]);
- }
-
- /* Signals ignored on entry to the shell cannot be trapped or reset. */
+ GETORIGSIG (sig);
if (original_signals[sig] == SIG_IGN)
- {
- sigmodes[sig] |= SIG_HARD_IGNORE;
- return;
- }
+ return;
}
/* Only change the system signal handler if SIG_NO_TRAP is not set.
sigmodes[sig] |= SIG_CHANGED;
}
-#define GET_ORIGINAL_SIGNAL(sig) \
- if (sig && sig < NSIG && original_signals[sig] == IMPOSSIBLE_TRAP_HANDLER) \
- get_original_signal (sig)
-
static void
get_original_signal (sig)
int sig;
{
/* If we aren't sure the of the original value, then get it. */
- if (original_signals[sig] == (SigHandler *)IMPOSSIBLE_TRAP_HANDLER)
- {
- original_signals[sig] =
- (SigHandler *) set_signal_handler (sig, SIG_DFL);
- set_signal_handler (sig, original_signals[sig]);
+ if (sig > 0 && sig < NSIG && original_signals[sig] == (SigHandler *)IMPOSSIBLE_TRAP_HANDLER)
+ GETORIGSIG (sig);
+}
- /* Signals ignored on entry to the shell cannot be trapped. */
- if (original_signals[sig] == SIG_IGN)
- sigmodes[sig] |= SIG_HARD_IGNORE;
- }
+void
+get_all_original_signals ()
+{
+ register int i;
+
+ for (i = 1; i < NSIG; i++)
+ GET_ORIGINAL_SIGNAL (i);
+}
+
+void
+set_original_signal (sig, handler)
+ int sig;
+ SigHandler *handler;
+{
+ if (sig > 0 && sig < NSIG && original_signals[sig] == (SigHandler *)IMPOSSIBLE_TRAP_HANDLER)
+ SETORIGSIG (sig, handler);
}
/* Restore the default action for SIG; i.e., the action the shell
{
char *trap_command;
int code, function_code, retval;
+#if defined (ARRAY_VARS)
+ ARRAY *ps;
+#endif
trap_saved_exit_value = last_command_exit_value;
+#if defined (ARRAY_VARS)
+ ps = save_pipestatus_array ();
+#endif
function_code = 0;
/* Run the trap only if signal 0 is trapped and not ignored, and we are not
if (code == 0 && function_code == 0)
{
reset_parser ();
- parse_and_execute (trap_command, "exit trap", SEVAL_NONINT|SEVAL_NOHIST);
+ parse_and_execute (trap_command, "exit trap", SEVAL_NONINT|SEVAL_NOHIST|SEVAL_RESETLINE);
}
else if (code == ERREXIT)
retval = last_command_exit_value;
return retval;
}
+#if defined (ARRAY_VARS)
+ restore_pipestatus_array (ps);
+#endif
return (trap_saved_exit_value);
}
{
char *trap_command, *old_trap;
int trap_exit_value, *token_state;
- int save_return_catch_flag, function_code;
+ int save_return_catch_flag, function_code, flags;
procenv_t save_return_catch;
+ WORD_LIST *save_subst_varlist;
+#if defined (ARRAY_VARS)
+ ARRAY *ps;
+#endif
trap_exit_value = function_code = 0;
/* Run the trap only if SIG is trapped and not ignored, and we are not
running_trap = sig + 1;
trap_saved_exit_value = last_command_exit_value;
+#if defined (ARRAY_VARS)
+ ps = save_pipestatus_array ();
+#endif
token_state = save_token_state ();
+ save_subst_varlist = subst_assign_varlist;
+ subst_assign_varlist = 0;
/* If we're in a function, make sure return longjmps come here, too. */
save_return_catch_flag = return_catch_flag;
function_code = setjmp (return_catch);
}
+ flags = SEVAL_NONINT|SEVAL_NOHIST;
+ if (sig != DEBUG_TRAP && sig != RETURN_TRAP && sig != ERROR_TRAP)
+ flags |= SEVAL_RESETLINE;
if (function_code == 0)
- parse_and_execute (trap_command, tag, SEVAL_NONINT|SEVAL_NOHIST);
+ parse_and_execute (trap_command, tag, flags);
restore_token_state (token_state);
free (token_state);
+ subst_assign_varlist = save_subst_varlist;
+
trap_exit_value = last_command_exit_value;
last_command_exit_value = trap_saved_exit_value;
+#if defined (ARRAY_VARS)
+ restore_pipestatus_array (ps);
+#endif
running_trap = 0;
sigmodes[sig] &= ~SIG_INPROGRESS;
run_debug_trap ()
{
int trap_exit_value;
+ pid_t save_pgrp;
+ int save_pipe[2];
/* XXX - question: should the DEBUG trap inherit the RETURN trap? */
trap_exit_value = 0;
if ((sigmodes[DEBUG_TRAP] & SIG_TRAPPED) && ((sigmodes[DEBUG_TRAP] & SIG_IGNORED) == 0) && ((sigmodes[DEBUG_TRAP] & SIG_INPROGRESS) == 0))
{
+#if defined (JOB_CONTROL)
+ save_pgrp = pipeline_pgrp;
+ pipeline_pgrp = 0;
+ save_pipeline (1);
+# if defined (PGRP_PIPE)
+ save_pgrp_pipe (save_pipe, 1);
+# endif
+ stop_making_children ();
+#endif
+
trap_exit_value = _run_trap_internal (DEBUG_TRAP, "debug trap");
+
+#if defined (JOB_CONTROL)
+ pipeline_pgrp = save_pgrp;
+ restore_pipeline (1);
+# if defined (PGRP_PIPE)
+ close_pgrp_pipe ();
+ restore_pgrp_pipe (save_pipe);
+# endif
+ if (pipeline_pgrp > 0)
+ give_terminal_to (pipeline_pgrp, 1);
+ notify_and_cleanup ();
+#endif
#if defined (DEBUGGER)
/* If we're in the debugger and the DEBUG trap returns 2 while we're in
_run_trap_internal (SIGINT, "interrupt trap");
}
-#ifdef INCLUDE_UNUSED
/* Free all the allocated strings in the list of traps and reset the trap
- values to the default. */
+ values to the default. Intended to be called from subshells that want
+ to complete work done by reset_signal_handlers upon execution of a
+ subsequent `trap' command that changes a signal's disposition. */
void
free_trap_strings ()
{
register int i;
for (i = 0; i < BASH_NSIG; i++)
- {
- free_trap_command (i);
- trap_list[i] = (char *)DEFAULT_SIG;
- sigmodes[i] &= ~SIG_TRAPPED;
- }
+ free_trap_string (i);
trap_list[DEBUG_TRAP] = trap_list[EXIT_TRAP] = trap_list[ERROR_TRAP] = trap_list[RETURN_TRAP] = (char *)NULL;
}
-#endif
-/* Reset the handler for SIG to the original value. */
+/* Free a trap command string associated with SIG without changing signal
+ disposition. Intended to be called from free_trap_strings() */
+static void
+free_trap_string (sig)
+ int sig;
+{
+ change_signal (sig, (char *)DEFAULT_SIG);
+ sigmodes[sig] &= ~SIG_TRAPPED;
+}
+
+/* Reset the handler for SIG to the original value but leave the trap string
+ in place. */
static void
reset_signal (sig)
int sig;
`functrace' or `errtrace' options have been set, then let command
substitutions inherit them. Let command substitution inherit the
RETURN trap if we're in the debugger and tracing functions. */
-#if defined (DEBUGGER)
- if (debugging_mode == 0 || function_trace_mode == 0)
-#endif
- sigmodes[DEBUG_TRAP] &= ~SIG_TRAPPED;
-#if defined (DEBUGGER)
- if (debugging_mode == 0 || error_trace_mode == 0)
-#endif
+ if (function_trace_mode == 0)
+ {
+ sigmodes[DEBUG_TRAP] &= ~SIG_TRAPPED;
+ sigmodes[RETURN_TRAP] &= ~SIG_TRAPPED;
+ }
+ if (error_trace_mode == 0)
sigmodes[ERROR_TRAP] &= ~SIG_TRAPPED;
-#if defined (DEBUGGER)
- if (debugging_mode == 0 || function_trace_mode == 0)
-#endif
- sigmodes[RETURN_TRAP] &= ~SIG_TRAPPED;
}
/* Reset trapped signals to their original values, but don't free the
- trap strings. Called by the command substitution code. */
+ trap strings. Called by the command substitution code and other places
+ that create a "subshell environment". */
void
reset_signal_handlers ()
{
return (sigmodes[sig] & SIG_IGNORED);
}
+int
+signal_is_hard_ignored (sig)
+ int sig;
+{
+ return (sigmodes[sig] & SIG_HARD_IGNORE);
+}
+
void
set_signal_ignored (sig)
int sig;