/* signals.c -- signal handling support for readline. */
-/* Copyright (C) 1987-2005 Free Software Foundation, Inc.
+/* Copyright (C) 1987-2017 Free Software Foundation, Inc.
- This file is part of the GNU Readline Library, a library for
- reading lines of text with interactive input and history editing.
+ This file is part of the GNU Readline Library (Readline), a library
+ for reading lines of text with interactive input and history editing.
- The GNU Readline Library 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
+ Readline 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.
- The GNU Readline Library 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
+ Readline 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.
- The GNU General Public License is often shipped with GNU software, and
- is generally kept in a file called COPYING or LICENSE. If you do not
- have a copy of the license, 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 Readline. If not, see <http://www.gnu.org/licenses/>.
+*/
+
#define READLINE_LIBRARY
#if defined (HAVE_CONFIG_H)
# include <sys/ioctl.h>
#endif /* GWINSZ_IN_SYS_IOCTL */
-#if defined (HANDLE_SIGNALS)
/* Some standard library routines. */
#include "readline.h"
#include "history.h"
#include "rlprivate.h"
+#if defined (HANDLE_SIGNALS)
+
#if !defined (RETSIGTYPE)
# if defined (VOID_SIGHANDLER)
# define RETSIGTYPE void
static SigHandler *rl_set_sighandler PARAMS((int, SigHandler *, sighandler_cxt *));
static void rl_maybe_set_sighandler PARAMS((int, SigHandler *, sighandler_cxt *));
+static void rl_maybe_restore_sighandler PARAMS((int, sighandler_cxt *));
+static RETSIGTYPE rl_signal_handler PARAMS((int));
+static RETSIGTYPE _rl_handle_signal PARAMS((int));
+
/* Exported variables for use by applications. */
/* If non-zero, readline will install its own signal handlers for
- SIGINT, SIGTERM, SIGQUIT, SIGALRM, SIGTSTP, SIGTTIN, and SIGTTOU. */
+ SIGINT, SIGTERM, SIGHUP, SIGQUIT, SIGALRM, SIGTSTP, SIGTTIN, and SIGTTOU. */
int rl_catch_signals = 1;
/* If non-zero, readline will install a signal handler for SIGWINCH. */
int rl_catch_sigwinch = 0; /* for the readline state struct in readline.c */
#endif
+/* Private variables. */
+int _rl_interrupt_immediately = 0;
+int volatile _rl_caught_signal = 0; /* should be sig_atomic_t, but that requires including <signal.h> everywhere */
+
+/* If non-zero, print characters corresponding to received signals as long as
+ the user has indicated his desire to do so (_rl_echo_control_chars). */
+int _rl_echoctl = 0;
+
+int _rl_intr_char = 0;
+int _rl_quit_char = 0;
+int _rl_susp_char = 0;
+
static int signals_set_flag;
static int sigwinch_set_flag;
+#if defined (HAVE_POSIX_SIGNALS)
+sigset_t _rl_orig_sigset;
+#endif /* !HAVE_POSIX_SIGNALS */
+
/* **************************************************************** */
/* */
/* Signal Handling */
/* */
/* **************************************************************** */
-static sighandler_cxt old_int, old_term, old_alrm, old_quit;
+static sighandler_cxt old_int, old_term, old_hup, old_alrm, old_quit;
#if defined (SIGTSTP)
static sighandler_cxt old_tstp, old_ttou, old_ttin;
#endif
static sighandler_cxt old_winch;
#endif
+_rl_sigcleanup_func_t *_rl_sigcleanup;
+void *_rl_sigcleanarg;
+
/* Readline signal handler functions. */
+/* Called from RL_CHECK_SIGNALS() macro */
+RETSIGTYPE
+_rl_signal_handler (int sig)
+{
+ _rl_caught_signal = 0; /* XXX */
+
+#if defined (SIGWINCH)
+ if (sig == SIGWINCH)
+ {
+ rl_resize_terminal ();
+ /* XXX - experimental for now */
+ /* Call a signal hook because though we called the original signal handler
+ in rl_sigwinch_handler below, we will not resend the signal to
+ ourselves. */
+ if (rl_signal_event_hook)
+ (*rl_signal_event_hook) ();
+ }
+ else
+#endif
+ _rl_handle_signal (sig);
+
+ SIGHANDLER_RETURN;
+}
+
static RETSIGTYPE
-rl_signal_handler (sig)
- int sig;
+rl_signal_handler (int sig)
+{
+ if (_rl_interrupt_immediately)
+ {
+ _rl_interrupt_immediately = 0;
+ _rl_handle_signal (sig);
+ }
+ else
+ _rl_caught_signal = sig;
+
+ SIGHANDLER_RETURN;
+}
+
+static RETSIGTYPE
+_rl_handle_signal (int sig)
{
#if defined (HAVE_POSIX_SIGNALS)
sigset_t set;
rl_set_sighandler (sig, SIG_IGN, &dummy_cxt);
#endif /* !HAVE_BSD_SIGNALS && !HAVE_POSIX_SIGNALS */
+ /* If there's a sig cleanup function registered, call it and `deregister'
+ the cleanup function to avoid multiple calls */
+ if (_rl_sigcleanup)
+ {
+ (*_rl_sigcleanup) (sig, _rl_sigcleanarg);
+ _rl_sigcleanup = 0;
+ _rl_sigcleanarg = 0;
+ }
+
switch (sig)
{
case SIGINT:
+ _rl_reset_completion_state ();
rl_free_line_state ();
+#if defined (READLINE_CALLBACKS)
+ rl_callback_sigcleanup ();
+#endif
+
/* FALLTHROUGH */
- case SIGTERM:
#if defined (SIGTSTP)
case SIGTSTP:
- case SIGTTOU:
case SIGTTIN:
+# if defined (HAVE_POSIX_SIGNALS)
+ /* Block SIGTTOU so we can restore the terminal settings to something
+ sane without stopping on SIGTTOU if we have been placed into the
+ background. Even trying to get the current terminal pgrp with
+ tcgetpgrp() will generate SIGTTOU, so we don't bother. Don't bother
+ doing this if we've been stopped on SIGTTOU; it's aready too late. */
+ sigemptyset (&set);
+ sigaddset (&set, SIGTTOU);
+ sigprocmask (SIG_BLOCK, &set, (sigset_t *)NULL);
+# endif
+ case SIGTTOU:
#endif /* SIGTSTP */
+ case SIGTERM:
+#if defined (SIGHUP)
+ case SIGHUP:
+#endif
#if defined (SIGALRM)
case SIGALRM:
#endif
#if defined (SIGQUIT)
case SIGQUIT:
#endif
+ rl_echo_signal_char (sig);
rl_cleanup_after_signal ();
#if defined (HAVE_POSIX_SIGNALS)
+# if defined (SIGTSTP)
+ /* Unblock SIGTTOU blocked above */
+ if (sig == SIGTTIN || sig == SIGTSTP)
+ sigprocmask (SIG_UNBLOCK, &set, (sigset_t *)NULL);
+# endif
+
+ sigemptyset (&set);
sigprocmask (SIG_BLOCK, (sigset_t *)NULL, &set);
sigdelset (&set, sig);
#else /* !HAVE_POSIX_SIGNALS */
# endif /* HAVE_BSD_SIGNALS */
#endif /* !HAVE_POSIX_SIGNALS */
- rl_reset_after_signal ();
+ rl_reset_after_signal ();
}
RL_UNSETSTATE(RL_STATE_SIGHANDLER);
#if defined (SIGWINCH)
static RETSIGTYPE
-rl_sigwinch_handler (sig)
- int sig;
+rl_sigwinch_handler (int sig)
{
SigHandler *oh;
#endif
RL_SETSTATE(RL_STATE_SIGHANDLER);
- rl_resize_terminal ();
+ _rl_caught_signal = sig;
/* If another sigwinch handler has been installed, call it. */
oh = (SigHandler *)old_winch.sa_handler;
#if !defined (HAVE_POSIX_SIGNALS)
static int
-rl_sigaction (sig, nh, oh)
- int sig;
- sighandler_cxt *nh, *oh;
+rl_sigaction (int sig, sighandler_cxt *nh, sighandler_cxt *oh)
{
oh->sa_handler = signal (sig, nh->sa_handler);
return 0;
information in OHANDLER. Return the old signal handler, like
signal(). */
static SigHandler *
-rl_set_sighandler (sig, handler, ohandler)
- int sig;
- SigHandler *handler;
- sighandler_cxt *ohandler;
+rl_set_sighandler (int sig, SigHandler *handler, sighandler_cxt *ohandler)
{
sighandler_cxt old_handler;
#if defined (HAVE_POSIX_SIGNALS)
struct sigaction act;
act.sa_handler = handler;
+# if defined (SIGWINCH)
act.sa_flags = (sig == SIGWINCH) ? SA_RESTART : 0;
+# else
+ act.sa_flags = 0;
+# endif /* SIGWINCH */
sigemptyset (&act.sa_mask);
sigemptyset (&ohandler->sa_mask);
sigaction (sig, &act, &old_handler);
return (ohandler->sa_handler);
}
+/* Set disposition of SIG to HANDLER, returning old state in OHANDLER. Don't
+ change disposition if OHANDLER indicates the signal was ignored. */
static void
-rl_maybe_set_sighandler (sig, handler, ohandler)
- int sig;
- SigHandler *handler;
- sighandler_cxt *ohandler;
+rl_maybe_set_sighandler (int sig, SigHandler *handler, sighandler_cxt *ohandler)
{
sighandler_cxt dummy;
SigHandler *oh;
sigemptyset (&dummy.sa_mask);
+ dummy.sa_flags = 0;
oh = rl_set_sighandler (sig, handler, ohandler);
if (oh == (SigHandler *)SIG_IGN)
rl_sigaction (sig, ohandler, &dummy);
}
+/* Set the disposition of SIG to HANDLER, if HANDLER->sa_handler indicates the
+ signal was not being ignored. MUST only be called for signals whose
+ disposition was changed using rl_maybe_set_sighandler or for which the
+ SIG_IGN check was performed inline (e.g., SIGALRM below). */
+static void
+rl_maybe_restore_sighandler (int sig, sighandler_cxt *handler)
+{
+ sighandler_cxt dummy;
+
+ sigemptyset (&dummy.sa_mask);
+ dummy.sa_flags = 0;
+ if (handler->sa_handler != SIG_IGN)
+ rl_sigaction (sig, handler, &dummy);
+}
+
int
-rl_set_signals ()
+rl_set_signals (void)
{
sighandler_cxt dummy;
SigHandler *oh;
+#if defined (HAVE_POSIX_SIGNALS)
+ static int sigmask_set = 0;
+ static sigset_t bset, oset;
+#endif
+
+#if defined (HAVE_POSIX_SIGNALS)
+ if (rl_catch_signals && sigmask_set == 0)
+ {
+ sigemptyset (&bset);
+
+ sigaddset (&bset, SIGINT);
+ sigaddset (&bset, SIGTERM);
+#if defined (SIGHUP)
+ sigaddset (&bset, SIGHUP);
+#endif
+#if defined (SIGQUIT)
+ sigaddset (&bset, SIGQUIT);
+#endif
+#if defined (SIGALRM)
+ sigaddset (&bset, SIGALRM);
+#endif
+#if defined (SIGTSTP)
+ sigaddset (&bset, SIGTSTP);
+#endif
+#if defined (SIGTTIN)
+ sigaddset (&bset, SIGTTIN);
+#endif
+#if defined (SIGTTOU)
+ sigaddset (&bset, SIGTTOU);
+#endif
+ sigmask_set = 1;
+ }
+#endif /* HAVE_POSIX_SIGNALS */
if (rl_catch_signals && signals_set_flag == 0)
{
+#if defined (HAVE_POSIX_SIGNALS)
+ sigemptyset (&_rl_orig_sigset);
+ sigprocmask (SIG_BLOCK, &bset, &_rl_orig_sigset);
+#endif
+
rl_maybe_set_sighandler (SIGINT, rl_signal_handler, &old_int);
rl_maybe_set_sighandler (SIGTERM, rl_signal_handler, &old_term);
+#if defined (SIGHUP)
+ rl_maybe_set_sighandler (SIGHUP, rl_signal_handler, &old_hup);
+#endif
#if defined (SIGQUIT)
rl_maybe_set_sighandler (SIGQUIT, rl_signal_handler, &old_quit);
#endif
#endif /* SIGTTIN */
signals_set_flag = 1;
+
+#if defined (HAVE_POSIX_SIGNALS)
+ sigprocmask (SIG_SETMASK, &_rl_orig_sigset, (sigset_t *)NULL);
+#endif
+ }
+ else if (rl_catch_signals == 0)
+ {
+#if defined (HAVE_POSIX_SIGNALS)
+ sigemptyset (&_rl_orig_sigset);
+ sigprocmask (SIG_BLOCK, (sigset_t *)NULL, &_rl_orig_sigset);
+#endif
}
#if defined (SIGWINCH)
}
int
-rl_clear_signals ()
+rl_clear_signals (void)
{
sighandler_cxt dummy;
if (rl_catch_signals && signals_set_flag == 1)
{
- sigemptyset (&dummy.sa_mask);
-
- rl_sigaction (SIGINT, &old_int, &dummy);
- rl_sigaction (SIGTERM, &old_term, &dummy);
+ /* Since rl_maybe_set_sighandler doesn't override a SIG_IGN handler,
+ we should in theory not have to restore a handler where
+ old_xxx.sa_handler == SIG_IGN. That's what rl_maybe_restore_sighandler
+ does. Fewer system calls should reduce readline's per-line
+ overhead */
+ rl_maybe_restore_sighandler (SIGINT, &old_int);
+ rl_maybe_restore_sighandler (SIGTERM, &old_term);
+#if defined (SIGHUP)
+ rl_maybe_restore_sighandler (SIGHUP, &old_hup);
+#endif
#if defined (SIGQUIT)
- rl_sigaction (SIGQUIT, &old_quit, &dummy);
+ rl_maybe_restore_sighandler (SIGQUIT, &old_quit);
#endif
#if defined (SIGALRM)
- rl_sigaction (SIGALRM, &old_alrm, &dummy);
+ rl_maybe_restore_sighandler (SIGALRM, &old_alrm);
#endif
#if defined (SIGTSTP)
- rl_sigaction (SIGTSTP, &old_tstp, &dummy);
+ rl_maybe_restore_sighandler (SIGTSTP, &old_tstp);
#endif /* SIGTSTP */
#if defined (SIGTTOU)
- rl_sigaction (SIGTTOU, &old_ttou, &dummy);
+ rl_maybe_restore_sighandler (SIGTTOU, &old_ttou);
#endif /* SIGTTOU */
#if defined (SIGTTIN)
- rl_sigaction (SIGTTIN, &old_ttin, &dummy);
+ rl_maybe_restore_sighandler (SIGTTIN, &old_ttin);
#endif /* SIGTTIN */
signals_set_flag = 0;
/* Clean up the terminal and readline state after catching a signal, before
resending it to the calling application. */
void
-rl_cleanup_after_signal ()
+rl_cleanup_after_signal (void)
{
_rl_clean_up_for_exit ();
if (rl_deprep_term_function)
(*rl_deprep_term_function) ();
- rl_clear_signals ();
rl_clear_pending_input ();
+ rl_clear_signals ();
}
/* Reset the terminal and readline state after a signal handler returns. */
void
-rl_reset_after_signal ()
+rl_reset_after_signal (void)
{
if (rl_prep_term_function)
(*rl_prep_term_function) (_rl_meta_flag);
numeric arguments in process) after catching a signal, before calling
rl_cleanup_after_signal(). */
void
-rl_free_line_state ()
+rl_free_line_state (void)
{
register HIST_ENTRY *entry;
_rl_reset_argument ();
}
+int
+rl_pending_signal (void)
+{
+ return (_rl_caught_signal);
+}
+
+void
+rl_check_signals (void)
+{
+ RL_CHECK_SIGNALS ();
+}
#endif /* HANDLE_SIGNALS */
+
+/* **************************************************************** */
+/* */
+/* SIGINT Management */
+/* */
+/* **************************************************************** */
+
+#if defined (HAVE_POSIX_SIGNALS)
+static sigset_t sigint_set, sigint_oset;
+static sigset_t sigwinch_set, sigwinch_oset;
+#else /* !HAVE_POSIX_SIGNALS */
+# if defined (HAVE_BSD_SIGNALS)
+static int sigint_oldmask;
+static int sigwinch_oldmask;
+# endif /* HAVE_BSD_SIGNALS */
+#endif /* !HAVE_POSIX_SIGNALS */
+
+static int sigint_blocked;
+static int sigwinch_blocked;
+
+/* Cause SIGINT to not be delivered until the corresponding call to
+ release_sigint(). */
+void
+_rl_block_sigint (void)
+{
+ if (sigint_blocked)
+ return;
+
+ sigint_blocked = 1;
+}
+
+/* Allow SIGINT to be delivered. */
+void
+_rl_release_sigint (void)
+{
+ if (sigint_blocked == 0)
+ return;
+
+ sigint_blocked = 0;
+ RL_CHECK_SIGNALS ();
+}
+
+/* Cause SIGWINCH to not be delivered until the corresponding call to
+ release_sigwinch(). */
+void
+_rl_block_sigwinch (void)
+{
+ if (sigwinch_blocked)
+ return;
+
+#if defined (SIGWINCH)
+
+#if defined (HAVE_POSIX_SIGNALS)
+ sigemptyset (&sigwinch_set);
+ sigemptyset (&sigwinch_oset);
+ sigaddset (&sigwinch_set, SIGWINCH);
+ sigprocmask (SIG_BLOCK, &sigwinch_set, &sigwinch_oset);
+#else /* !HAVE_POSIX_SIGNALS */
+# if defined (HAVE_BSD_SIGNALS)
+ sigwinch_oldmask = sigblock (sigmask (SIGWINCH));
+# else /* !HAVE_BSD_SIGNALS */
+# if defined (HAVE_USG_SIGHOLD)
+ sighold (SIGWINCH);
+# endif /* HAVE_USG_SIGHOLD */
+# endif /* !HAVE_BSD_SIGNALS */
+#endif /* !HAVE_POSIX_SIGNALS */
+
+#endif /* SIGWINCH */
+
+ sigwinch_blocked = 1;
+}
+
+/* Allow SIGWINCH to be delivered. */
+void
+_rl_release_sigwinch (void)
+{
+ if (sigwinch_blocked == 0)
+ return;
+
+#if defined (SIGWINCH)
+
+#if defined (HAVE_POSIX_SIGNALS)
+ sigprocmask (SIG_SETMASK, &sigwinch_oset, (sigset_t *)NULL);
+#else
+# if defined (HAVE_BSD_SIGNALS)
+ sigsetmask (sigwinch_oldmask);
+# else /* !HAVE_BSD_SIGNALS */
+# if defined (HAVE_USG_SIGHOLD)
+ sigrelse (SIGWINCH);
+# endif /* HAVE_USG_SIGHOLD */
+# endif /* !HAVE_BSD_SIGNALS */
+#endif /* !HAVE_POSIX_SIGNALS */
+
+#endif /* SIGWINCH */
+
+ sigwinch_blocked = 0;
+}
+
+/* **************************************************************** */
+/* */
+/* Echoing special control characters */
+/* */
+/* **************************************************************** */
+void
+rl_echo_signal_char (int sig)
+{
+ char cstr[3];
+ int cslen, c;
+
+ if (_rl_echoctl == 0 || _rl_echo_control_chars == 0)
+ return;
+
+ switch (sig)
+ {
+ case SIGINT: c = _rl_intr_char; break;
+#if defined (SIGQUIT)
+ case SIGQUIT: c = _rl_quit_char; break;
+#endif
+#if defined (SIGTSTP)
+ case SIGTSTP: c = _rl_susp_char; break;
+#endif
+ default: return;
+ }
+
+ if (CTRL_CHAR (c) || c == RUBOUT)
+ {
+ cstr[0] = '^';
+ cstr[1] = CTRL_CHAR (c) ? UNCTRL (c) : '?';
+ cstr[cslen = 2] = '\0';
+ }
+ else
+ {
+ cstr[0] = c;
+ cstr[cslen = 1] = '\0';
+ }
+
+ _rl_output_some_chars (cstr, cslen);
+}