/* sig.c - interface for shell signal handlers and signal initialization. */
-/* Copyright (C) 1994 Free Software Foundation, Inc.
+/* Copyright (C) 1994-2015 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 "trap.h"
#include "builtins/common.h"
+#include "builtins/builtext.h"
#if defined (READLINE)
# include "bashline.h"
+# include <readline/readline.h>
#endif
#if defined (HISTORY)
extern int last_command_exit_value;
extern int last_command_exit_signal;
extern int return_catch_flag;
-extern int loop_level, continuing, breaking;
+extern int running_trap;
+extern int loop_level, continuing, breaking, funcnest;
+extern int executing_list;
+extern int comsub_ignore_return;
extern int parse_and_execute_level, shell_initialized;
+#if defined (HISTORY)
+extern int history_lines_this_session;
+#endif
+extern int no_line_editing;
+extern int wait_signal_received;
+extern int wait_intr_flag;
+extern sh_builtin_func_t *this_shell_builtin;
+
+extern void initialize_siglist ();
+
+#if !defined (JOB_CONTROL)
+extern void initialize_job_signals __P((void));
+#endif
/* Non-zero after SIGINT. */
-int interrupt_state;
+volatile sig_atomic_t interrupt_state = 0;
+
+/* Non-zero after SIGWINCH */
+volatile sig_atomic_t sigwinch_received = 0;
+
+/* Non-zero after SIGTERM */
+volatile sig_atomic_t sigterm_received = 0;
+
+/* Set to the value of any terminating signal received. */
+volatile sig_atomic_t terminating_signal = 0;
/* The environment at the top-level R-E loop. We use this in
the case of error return. */
/* When non-zero, we throw_to_top_level (). */
int interrupt_immediately = 0;
+/* When non-zero, we call the terminating signal handler immediately. */
+int terminate_immediately = 0;
+
+#if defined (SIGWINCH)
+static SigHandler *old_winch = (SigHandler *)SIG_DFL;
+#endif
+
static void initialize_shell_signals __P((void));
void
struct termsig {
int signum;
SigHandler *orig_handler;
+ int orig_flags;
};
#define NULL_HANDLER (SigHandler *)SIG_DFL
and so forth. */
static struct termsig terminating_signals[] = {
#ifdef SIGHUP
-{ SIGHUP, NULL_HANDLER },
+{ SIGHUP, NULL_HANDLER, 0 },
#endif
#ifdef SIGINT
-{ SIGINT, NULL_HANDLER },
+{ SIGINT, NULL_HANDLER, 0 },
#endif
#ifdef SIGILL
-{ SIGILL, NULL_HANDLER },
+{ SIGILL, NULL_HANDLER, 0 },
#endif
#ifdef SIGTRAP
-{ SIGTRAP, NULL_HANDLER },
+{ SIGTRAP, NULL_HANDLER, 0 },
#endif
#ifdef SIGIOT
-{ SIGIOT, NULL_HANDLER },
+{ SIGIOT, NULL_HANDLER, 0 },
#endif
#ifdef SIGDANGER
-{ SIGDANGER, NULL_HANDLER },
+{ SIGDANGER, NULL_HANDLER, 0 },
#endif
#ifdef SIGEMT
-{ SIGEMT, NULL_HANDLER },
+{ SIGEMT, NULL_HANDLER, 0 },
#endif
#ifdef SIGFPE
-{ SIGFPE, NULL_HANDLER },
+{ SIGFPE, NULL_HANDLER, 0 },
#endif
#ifdef SIGBUS
-{ SIGBUS, NULL_HANDLER },
+{ SIGBUS, NULL_HANDLER, 0 },
#endif
#ifdef SIGSEGV
-{ SIGSEGV, NULL_HANDLER },
+{ SIGSEGV, NULL_HANDLER, 0 },
#endif
#ifdef SIGSYS
-{ SIGSYS, NULL_HANDLER },
+{ SIGSYS, NULL_HANDLER, 0 },
#endif
#ifdef SIGPIPE
-{ SIGPIPE, NULL_HANDLER },
+{ SIGPIPE, NULL_HANDLER, 0 },
#endif
#ifdef SIGALRM
-{ SIGALRM, NULL_HANDLER },
+{ SIGALRM, NULL_HANDLER, 0 },
#endif
#ifdef SIGTERM
-{ SIGTERM, NULL_HANDLER },
+{ SIGTERM, NULL_HANDLER, 0 },
#endif
#ifdef SIGXCPU
-{ SIGXCPU, NULL_HANDLER },
+{ SIGXCPU, NULL_HANDLER, 0 },
#endif
#ifdef SIGXFSZ
-{ SIGXFSZ, NULL_HANDLER },
+{ SIGXFSZ, NULL_HANDLER, 0 },
#endif
#ifdef SIGVTALRM
-{ SIGVTALRM, NULL_HANDLER },
+{ SIGVTALRM, NULL_HANDLER, 0 },
#endif
#if 0
#ifdef SIGPROF
-{ SIGPROF, NULL_HANDLER },
+{ SIGPROF, NULL_HANDLER, 0 },
#endif
#endif
#ifdef SIGLOST
-{ SIGLOST, NULL_HANDLER },
+{ SIGLOST, NULL_HANDLER, 0 },
#endif
#ifdef SIGUSR1
-{ SIGUSR1, NULL_HANDLER },
+{ SIGUSR1, NULL_HANDLER, 0 },
#endif
#ifdef SIGUSR2
-{ SIGUSR2, NULL_HANDLER },
+{ SIGUSR2, NULL_HANDLER, 0 },
#endif
};
#define XSIG(x) (terminating_signals[x].signum)
#define XHANDLER(x) (terminating_signals[x].orig_handler)
+#define XSAFLAGS(x) (terminating_signals[x].orig_flags)
static int termsigs_initialized = 0;
/* Initialize signals that will terminate the shell to do some
unwind protection. For non-interactive shells, we only call
- this when a trap is defined for EXIT (0). */
+ this when a trap is defined for EXIT (0) or when trap is run
+ to display signal dispositions. */
void
initialize_terminating_signals ()
{
this is possible in Posix. Unfortunately, we have to call signal ()
on non-Posix systems for each signal in terminating_signals. */
#if defined (HAVE_POSIX_SIGNALS)
- act.sa_handler = termination_unwind_protect;
+ act.sa_handler = termsig_sighandler;
act.sa_flags = 0;
sigemptyset (&act.sa_mask);
sigemptyset (&oact.sa_mask);
sigaction (XSIG (i), &act, &oact);
XHANDLER(i) = oact.sa_handler;
+ XSAFLAGS(i) = oact.sa_flags;
/* Don't do anything with signals that are ignored at shell entry
if the shell is not interactive. */
- if (!interactive_shell && XHANDLER (i) == SIG_IGN)
+ /* XXX - should we do this for interactive shells, too? */
+ if (interactive_shell == 0 && XHANDLER (i) == SIG_IGN)
{
sigaction (XSIG (i), &oact, &act);
- set_signal_ignored (XSIG (i));
+ set_signal_hard_ignored (XSIG (i));
}
#if defined (SIGPROF) && !defined (_MINIX)
if (XSIG (i) == SIGPROF && XHANDLER (i) != SIG_DFL && XHANDLER (i) != SIG_IGN)
if (signal_is_trapped (XSIG (i)))
continue;
- XHANDLER(i) = signal (XSIG (i), termination_unwind_protect);
+ XHANDLER(i) = signal (XSIG (i), termsig_sighandler);
+ XSAFLAGS(i) = 0;
/* Don't do anything with signals that are ignored at shell entry
if the shell is not interactive. */
- if (!interactive_shell && XHANDLER (i) == SIG_IGN)
+ /* XXX - should we do this for interactive shells, too? */
+ if (interactive_shell == 0 && XHANDLER (i) == SIG_IGN)
{
signal (XSIG (i), SIG_IGN);
- set_signal_ignored (XSIG (i));
+ set_signal_hard_ignored (XSIG (i));
}
#ifdef SIGPROF
if (XSIG (i) == SIGPROF && XHANDLER (i) != SIG_DFL && XHANDLER (i) != SIG_IGN)
if (interactive)
{
set_signal_handler (SIGINT, sigint_sighandler);
- set_signal_handler (SIGTERM, SIG_IGN);
+ get_original_signal (SIGTERM);
+ if (signal_is_hard_ignored (SIGTERM) == 0)
+ set_signal_handler (SIGTERM, sigterm_sighandler);
+ set_sigwinch_handler ();
}
}
continue;
act.sa_handler = XHANDLER (i);
+ act.sa_flags = XSAFLAGS (i);
sigaction (XSIG (i), &act, (struct sigaction *) NULL);
}
#else /* !HAVE_POSIX_SIGNALS */
signal (XSIG (i), XHANDLER (i));
}
#endif /* !HAVE_POSIX_SIGNALS */
+
+ termsigs_initialized = 0;
}
#undef XSIG
#undef XHANDLER
+/* Run some of the cleanups that should be performed when we run
+ jump_to_top_level from a builtin command context. XXX - might want to
+ also call reset_parser here. */
+void
+top_level_cleanup ()
+{
+ /* Clean up string parser environment. */
+ while (parse_and_execute_level)
+ parse_and_execute_cleanup ();
+
+#if defined (PROCESS_SUBSTITUTION)
+ unlink_fifo_list ();
+#endif /* PROCESS_SUBSTITUTION */
+
+ run_unwind_protects ();
+ loop_level = continuing = breaking = funcnest = 0;
+ executing_list = comsub_ignore_return = return_catch_flag = wait_intr_flag = 0;
+}
+
/* What to do when we've been interrupted, and it is safe to handle it. */
void
throw_to_top_level ()
if (interrupt_state)
{
+ if (last_command_exit_value < 128)
+ last_command_exit_value = 128 + SIGINT;
print_newline = 1;
DELINTERRUPT;
}
(last_command_exit_value - 128) : 0;
last_command_exit_value |= 128;
- /* Run any traps set on SIGINT. */
- run_interrupt_trap ();
+ /* Run any traps set on SIGINT, mostly for interactive shells */
+ if (signal_is_trapped (SIGINT))
+ run_interrupt_trap (1);
- /* Cleanup string parser environment. */
+ /* Clean up string parser environment. */
while (parse_and_execute_level)
parse_and_execute_cleanup ();
+ if (running_trap > 0)
+ run_trap_cleanup (running_trap - 1);
+
#if defined (JOB_CONTROL)
give_terminal_to (shell_pgrp, 0);
#endif /* JOB_CONTROL */
#if defined (JOB_CONTROL) || defined (HAVE_POSIX_SIGNALS)
- /* This should not be necessary on systems using sigsetjmp/siglongjmp. */
+ /* This needs to stay because jobs.c:make_child() uses it without resetting
+ the signal mask. */
sigprocmask (SIG_SETMASK, &top_level_mask, (sigset_t *)NULL);
#endif
#if defined (READLINE)
if (interactive)
- bashline_reinitialize ();
+ bashline_reset ();
#endif /* READLINE */
#if defined (PROCESS_SUBSTITUTION)
#endif /* PROCESS_SUBSTITUTION */
run_unwind_protects ();
- loop_level = continuing = breaking = 0;
- return_catch_flag = 0;
+ loop_level = continuing = breaking = funcnest = 0;
+ executing_list = comsub_ignore_return = return_catch_flag = wait_intr_flag = 0;
if (interactive && print_newline)
{
jump_to_top_level (value)
int value;
{
- longjmp (top_level, value);
+ sh_longjmp (top_level, value);
}
sighandler
-termination_unwind_protect (sig)
+termsig_sighandler (sig)
+ int sig;
+{
+ /* If we get called twice with the same signal before handling it,
+ terminate right away. */
+ if (
+#ifdef SIGHUP
+ sig != SIGHUP &&
+#endif
+#ifdef SIGINT
+ sig != SIGINT &&
+#endif
+#ifdef SIGDANGER
+ sig != SIGDANGER &&
+#endif
+#ifdef SIGPIPE
+ sig != SIGPIPE &&
+#endif
+#ifdef SIGALRM
+ sig != SIGALRM &&
+#endif
+#ifdef SIGTERM
+ sig != SIGTERM &&
+#endif
+#ifdef SIGXCPU
+ sig != SIGXCPU &&
+#endif
+#ifdef SIGXFSZ
+ sig != SIGXFSZ &&
+#endif
+#ifdef SIGVTALRM
+ sig != SIGVTALRM &&
+#endif
+#ifdef SIGLOST
+ sig != SIGLOST &&
+#endif
+#ifdef SIGUSR1
+ sig != SIGUSR1 &&
+#endif
+#ifdef SIGUSR2
+ sig != SIGUSR2 &&
+#endif
+ sig == terminating_signal)
+ terminate_immediately = 1;
+
+ terminating_signal = sig;
+
+ /* XXX - should this also trigger when interrupt_immediately is set? */
+ if (terminate_immediately)
+ {
+#if defined (HISTORY)
+ /* XXX - will inhibit history file being written */
+# if defined (READLINE)
+ if (interactive_shell == 0 || interactive == 0 || (sig != SIGHUP && sig != SIGTERM) || no_line_editing || (RL_ISSTATE (RL_STATE_READCMD) == 0))
+# endif
+ history_lines_this_session = 0;
+#endif
+ terminate_immediately = 0;
+ termsig_handler (sig);
+ }
+
+#if defined (READLINE)
+ /* Set the event hook so readline will call it after the signal handlers
+ finish executing, so if this interrupted character input we can get
+ quick response. If readline is active or has modified the terminal we
+ need to set this no matter what the signal is, though the check for
+ RL_STATE_TERMPREPPED is possibly redundant. */
+ if (RL_ISSTATE (RL_STATE_SIGHANDLER) || RL_ISSTATE (RL_STATE_TERMPREPPED))
+ bashline_set_event_hook ();
+#endif
+
+ SIGRETURN (0);
+}
+
+void
+termsig_handler (sig)
int sig;
{
+ static int handling_termsig = 0;
+
+ /* Simple semaphore to keep this function from being executed multiple
+ times. Since we no longer are running as a signal handler, we don't
+ block multiple occurrences of the terminating signals while running. */
+ if (handling_termsig)
+ return;
+ handling_termsig = 1;
+ terminating_signal = 0; /* keep macro from re-testing true. */
+
+ /* I don't believe this condition ever tests true. */
if (sig == SIGINT && signal_is_trapped (SIGINT))
- run_interrupt_trap ();
+ run_interrupt_trap (0);
#if defined (HISTORY)
- if (interactive_shell && sig != SIGABRT)
+ /* If we don't do something like this, the history will not be saved when
+ an interactive shell is running in a terminal window that gets closed
+ with the `close' button. We can't test for RL_STATE_READCMD because
+ readline no longer handles SIGTERM synchronously. */
+ if (interactive_shell && interactive && (sig == SIGHUP || sig == SIGTERM) && remember_on_history)
maybe_save_shell_history ();
#endif /* HISTORY */
+ if (this_shell_builtin == read_builtin)
+ read_tty_cleanup ();
+
#if defined (JOB_CONTROL)
- if (interactive && sig == SIGHUP)
+ if (sig == SIGHUP && (interactive || (subshell_environment & (SUBSHELL_COMSUB|SUBSHELL_PROCSUB))))
hangup_all_jobs ();
- end_job_control ();
+ if ((subshell_environment & (SUBSHELL_COMSUB|SUBSHELL_PROCSUB)) == 0)
+ end_job_control ();
#endif /* JOB_CONTROL */
#if defined (PROCESS_SUBSTITUTION)
unlink_fifo_list ();
#endif /* PROCESS_SUBSTITUTION */
- run_exit_trap ();
+ /* Reset execution context */
+ loop_level = continuing = breaking = funcnest = 0;
+ executing_list = comsub_ignore_return = return_catch_flag = wait_intr_flag = 0;
+
+ run_exit_trap (); /* XXX - run exit trap possibly in signal context? */
set_signal_handler (sig, SIG_DFL);
kill (getpid (), sig);
-
- SIGRETURN (0);
}
/* What we really do when SIGINT occurs. */
if (interrupt_state == 0)
ADDINTERRUPT;
+ /* We will get here in interactive shells with job control active; allow
+ an interactive wait to be interrupted. wait_intr_flag is only set during
+ the execution of the wait builtin and when wait_intr_buf is valid. */
+ if (wait_intr_flag)
+ {
+ last_command_exit_value = 128 + sig;
+ wait_signal_received = sig;
+ SIGRETURN (0);
+ }
+
if (interrupt_immediately)
{
interrupt_immediately = 0;
+ last_command_exit_value = 128 + sig;
throw_to_top_level ();
}
+#if defined (READLINE)
+ /* Set the event hook so readline will call it after the signal handlers
+ finish executing, so if this interrupted character input we can get
+ quick response. */
+ else if (RL_ISSTATE (RL_STATE_SIGHANDLER))
+ bashline_set_event_hook ();
+#endif
+
+ SIGRETURN (0);
+}
+
+#if defined (SIGWINCH)
+sighandler
+sigwinch_sighandler (sig)
+ int sig;
+{
+#if defined (MUST_REINSTALL_SIGHANDLERS)
+ set_signal_handler (SIGWINCH, sigwinch_sighandler);
+#endif /* MUST_REINSTALL_SIGHANDLERS */
+ sigwinch_received = 1;
+ SIGRETURN (0);
+}
+#endif /* SIGWINCH */
+
+void
+set_sigwinch_handler ()
+{
+#if defined (SIGWINCH)
+ old_winch = set_signal_handler (SIGWINCH, sigwinch_sighandler);
+#endif
+}
+void
+unset_sigwinch_handler ()
+{
+#if defined (SIGWINCH)
+ set_signal_handler (SIGWINCH, old_winch);
+#endif
+}
+
+sighandler
+sigterm_sighandler (sig)
+ int sig;
+{
+ sigterm_received = 1; /* XXX - counter? */
SIGRETURN (0);
}
/* Signal functions used by the rest of the code. */
#if !defined (HAVE_POSIX_SIGNALS)
-#if defined (JOB_CONTROL)
/* Perform OPERATION on NEWSET, perhaps leaving information in OLDSET. */
sigprocmask (operation, newset, oldset)
int operation, *newset, *oldset;
break;
case SIG_SETMASK:
- sigsetmask (new);
+ old = sigsetmask (new);
break;
default:
if (oldset)
*oldset = old;
}
-#endif /* JOB_CONTROL */
#else
act.sa_handler = handler;
act.sa_flags = 0;
-#if 0
- if (sig == SIGALRM)
- act.sa_flags |= SA_INTERRUPT; /* XXX */
- else
+
+ /* XXX - bash-4.2 */
+ /* We don't want a child death to interrupt interruptible system calls, even
+ if we take the time to reap children */
+#if defined (SIGCHLD)
+ if (sig == SIGCHLD)
act.sa_flags |= SA_RESTART; /* XXX */
#endif
+ /* If we're installing a SIGTERM handler for interactive shells, we want
+ it to be as close to SIG_IGN as possible. */
+ if (sig == SIGTERM && handler == sigterm_sighandler)
+ act.sa_flags |= SA_RESTART; /* XXX */
+
sigemptyset (&act.sa_mask);
sigemptyset (&oact.sa_mask);
- sigaction (sig, &act, &oact);
- return (oact.sa_handler);
+ if (sigaction (sig, &act, &oact) == 0)
+ return (oact.sa_handler);
+ else
+ return (SIG_DFL);
}
#endif /* HAVE_POSIX_SIGNALS */
projects / thirdparty / bash.git / blobdiff