393 lines
11 KiB
C
393 lines
11 KiB
C
/* signals.c -- signal handling support for readline. */
|
|
|
|
/* Copyright (C) 1987, 1989, 1992 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.
|
|
|
|
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
|
|
(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
|
|
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. */
|
|
#define READLINE_LIBRARY
|
|
|
|
#if defined (HAVE_CONFIG_H)
|
|
# include <config.h>
|
|
#endif
|
|
|
|
#include <stdio.h> /* Just for NULL. Yuck. */
|
|
#include <sys/types.h>
|
|
#include <signal.h>
|
|
|
|
#if defined (HAVE_UNISTD_H)
|
|
# include <unistd.h>
|
|
#endif /* HAVE_UNISTD_H */
|
|
|
|
/* System-specific feature definitions and include files. */
|
|
#include "rldefs.h"
|
|
|
|
#if defined (GWINSZ_IN_SYS_IOCTL)
|
|
# 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 (RETSIGTYPE)
|
|
# if defined (VOID_SIGHANDLER)
|
|
# define RETSIGTYPE void
|
|
# else
|
|
# define RETSIGTYPE int
|
|
# endif /* !VOID_SIGHANDLER */
|
|
#endif /* !RETSIGTYPE */
|
|
|
|
#if defined (VOID_SIGHANDLER)
|
|
# define SIGHANDLER_RETURN return
|
|
#else
|
|
# define SIGHANDLER_RETURN return (0)
|
|
#endif
|
|
|
|
/* This typedef is equivalant to the one for Function; it allows us
|
|
to say SigHandler *foo = signal (SIGKILL, SIG_IGN); */
|
|
typedef RETSIGTYPE SigHandler ();
|
|
|
|
#if defined (HAVE_POSIX_SIGNALS)
|
|
typedef struct sigaction sighandler_cxt;
|
|
# define rl_sigaction(s, nh, oh) sigaction(s, nh, oh)
|
|
#else
|
|
typedef struct { SigHandler *sa_handler; int sa_mask, sa_flags; } sighandler_cxt;
|
|
# define sigemptyset(m)
|
|
#endif /* !HAVE_POSIX_SIGNALS */
|
|
|
|
static SigHandler *rl_set_sighandler __P((int, SigHandler *, sighandler_cxt *));
|
|
|
|
/* 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. */
|
|
int rl_catch_signals = 1;
|
|
|
|
/* If non-zero, readline will install a signal handler for SIGWINCH. */
|
|
#ifdef SIGWINCH
|
|
int rl_catch_sigwinch = 1;
|
|
#endif
|
|
|
|
static int signals_set_flag;
|
|
static int sigwinch_set_flag;
|
|
|
|
/* **************************************************************** */
|
|
/* */
|
|
/* Signal Handling */
|
|
/* */
|
|
/* **************************************************************** */
|
|
|
|
static sighandler_cxt old_int, old_term, old_alrm, old_quit;
|
|
#if defined (SIGTSTP)
|
|
static sighandler_cxt old_tstp, old_ttou, old_ttin;
|
|
#endif
|
|
#if defined (SIGWINCH)
|
|
static sighandler_cxt old_winch;
|
|
#endif
|
|
|
|
/* Readline signal handler functions. */
|
|
|
|
static RETSIGTYPE
|
|
rl_signal_handler (sig)
|
|
int sig;
|
|
{
|
|
#if defined (HAVE_POSIX_SIGNALS)
|
|
sigset_t set;
|
|
#else /* !HAVE_POSIX_SIGNALS */
|
|
# if defined (HAVE_BSD_SIGNALS)
|
|
long omask;
|
|
# else /* !HAVE_BSD_SIGNALS */
|
|
sighandler_cxt dummy_cxt; /* needed for rl_set_sighandler call */
|
|
# endif /* !HAVE_BSD_SIGNALS */
|
|
#endif /* !HAVE_POSIX_SIGNALS */
|
|
|
|
#if !defined (HAVE_BSD_SIGNALS) && !defined (HAVE_POSIX_SIGNALS)
|
|
/* Since the signal will not be blocked while we are in the signal
|
|
handler, ignore it until rl_clear_signals resets the catcher. */
|
|
if (sig == SIGINT || sig == SIGALRM)
|
|
rl_set_sighandler (sig, SIG_IGN, &dummy_cxt);
|
|
#endif /* !HAVE_BSD_SIGNALS && !HAVE_POSIX_SIGNALS */
|
|
|
|
switch (sig)
|
|
{
|
|
case SIGINT:
|
|
rl_free_line_state ();
|
|
/* FALLTHROUGH */
|
|
|
|
#if defined (SIGTSTP)
|
|
case SIGTSTP:
|
|
case SIGTTOU:
|
|
case SIGTTIN:
|
|
#endif /* SIGTSTP */
|
|
case SIGALRM:
|
|
case SIGTERM:
|
|
case SIGQUIT:
|
|
rl_cleanup_after_signal ();
|
|
|
|
#if defined (HAVE_POSIX_SIGNALS)
|
|
sigprocmask (SIG_BLOCK, (sigset_t *)NULL, &set);
|
|
sigdelset (&set, sig);
|
|
#else /* !HAVE_POSIX_SIGNALS */
|
|
# if defined (HAVE_BSD_SIGNALS)
|
|
omask = sigblock (0);
|
|
# endif /* HAVE_BSD_SIGNALS */
|
|
#endif /* !HAVE_POSIX_SIGNALS */
|
|
|
|
#if defined (__EMX__)
|
|
signal (sig, SIG_ACK);
|
|
#endif
|
|
|
|
kill (getpid (), sig);
|
|
|
|
/* Let the signal that we just sent through. */
|
|
#if defined (HAVE_POSIX_SIGNALS)
|
|
sigprocmask (SIG_SETMASK, &set, (sigset_t *)NULL);
|
|
#else /* !HAVE_POSIX_SIGNALS */
|
|
# if defined (HAVE_BSD_SIGNALS)
|
|
sigsetmask (omask & ~(sigmask (sig)));
|
|
# endif /* HAVE_BSD_SIGNALS */
|
|
#endif /* !HAVE_POSIX_SIGNALS */
|
|
|
|
rl_reset_after_signal ();
|
|
}
|
|
|
|
SIGHANDLER_RETURN;
|
|
}
|
|
|
|
#if defined (SIGWINCH)
|
|
static RETSIGTYPE
|
|
rl_sigwinch_handler (sig)
|
|
int sig;
|
|
{
|
|
SigHandler *oh;
|
|
|
|
#if defined (MUST_REINSTALL_SIGHANDLERS)
|
|
sighandler_cxt dummy_winch;
|
|
|
|
/* We don't want to change old_winch -- it holds the state of SIGWINCH
|
|
disposition set by the calling application. We need this state
|
|
because we call the application's SIGWINCH handler after updating
|
|
our own idea of the screen size. */
|
|
rl_set_sighandler (SIGWINCH, rl_sigwinch_handler, &dummy_winch);
|
|
#endif
|
|
|
|
rl_resize_terminal ();
|
|
|
|
/* If another sigwinch handler has been installed, call it. */
|
|
oh = (SigHandler *)old_winch.sa_handler;
|
|
if (oh && oh != (SigHandler *)SIG_IGN && oh != (SigHandler *)SIG_DFL)
|
|
(*oh) (sig);
|
|
|
|
SIGHANDLER_RETURN;
|
|
}
|
|
#endif /* SIGWINCH */
|
|
|
|
/* Functions to manage signal handling. */
|
|
|
|
#if !defined (HAVE_POSIX_SIGNALS)
|
|
static int
|
|
rl_sigaction (sig, nh, oh)
|
|
int sig;
|
|
sighandler_cxt *nh, *oh;
|
|
{
|
|
oh->sa_handler = signal (sig, nh->sa_handler);
|
|
return 0;
|
|
}
|
|
#endif /* !HAVE_POSIX_SIGNALS */
|
|
|
|
/* Set up a readline-specific signal handler, saving the old signal
|
|
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;
|
|
{
|
|
sighandler_cxt old_handler;
|
|
#if defined (HAVE_POSIX_SIGNALS)
|
|
struct sigaction act;
|
|
|
|
act.sa_handler = handler;
|
|
act.sa_flags = 0;
|
|
sigemptyset (&act.sa_mask);
|
|
sigemptyset (&ohandler->sa_mask);
|
|
sigaction (sig, &act, &old_handler);
|
|
#else
|
|
old_handler.sa_handler = (SigHandler *)signal (sig, handler);
|
|
#endif /* !HAVE_POSIX_SIGNALS */
|
|
|
|
/* XXX -- assume we have memcpy */
|
|
/* If rl_set_signals is called twice in a row, don't set the old handler to
|
|
rl_signal_handler, because that would cause infinite recursion. */
|
|
if (handler != rl_signal_handler || old_handler.sa_handler != rl_signal_handler)
|
|
memcpy (ohandler, &old_handler, sizeof (sighandler_cxt));
|
|
|
|
return (ohandler->sa_handler);
|
|
}
|
|
|
|
static void
|
|
rl_maybe_set_sighandler (sig, handler, ohandler)
|
|
int sig;
|
|
SigHandler *handler;
|
|
sighandler_cxt *ohandler;
|
|
{
|
|
sighandler_cxt dummy;
|
|
SigHandler *oh;
|
|
|
|
sigemptyset (&dummy.sa_mask);
|
|
oh = rl_set_sighandler (sig, handler, ohandler);
|
|
if (oh == (SigHandler *)SIG_IGN)
|
|
rl_sigaction (sig, ohandler, &dummy);
|
|
}
|
|
|
|
int
|
|
rl_set_signals ()
|
|
{
|
|
sighandler_cxt dummy;
|
|
SigHandler *oh;
|
|
|
|
if (rl_catch_signals && signals_set_flag == 0)
|
|
{
|
|
rl_maybe_set_sighandler (SIGINT, rl_signal_handler, &old_int);
|
|
rl_maybe_set_sighandler (SIGTERM, rl_signal_handler, &old_term);
|
|
rl_maybe_set_sighandler (SIGQUIT, rl_signal_handler, &old_quit);
|
|
|
|
oh = rl_set_sighandler (SIGALRM, rl_signal_handler, &old_alrm);
|
|
if (oh == (SigHandler *)SIG_IGN)
|
|
rl_sigaction (SIGALRM, &old_alrm, &dummy);
|
|
#if defined (HAVE_POSIX_SIGNALS) && defined (SA_RESTART)
|
|
/* If the application using readline has already installed a signal
|
|
handler with SA_RESTART, SIGALRM will cause reads to be restarted
|
|
automatically, so readline should just get out of the way. Since
|
|
we tested for SIG_IGN above, we can just test for SIG_DFL here. */
|
|
if (oh != (SigHandler *)SIG_DFL && (old_alrm.sa_flags & SA_RESTART))
|
|
rl_sigaction (SIGALRM, &old_alrm, &dummy);
|
|
#endif /* HAVE_POSIX_SIGNALS */
|
|
|
|
#if defined (SIGTSTP)
|
|
rl_maybe_set_sighandler (SIGTSTP, rl_signal_handler, &old_tstp);
|
|
#endif /* SIGTSTP */
|
|
|
|
#if defined (SIGTTOU)
|
|
rl_maybe_set_sighandler (SIGTTOU, rl_signal_handler, &old_ttou);
|
|
#endif /* SIGTTOU */
|
|
|
|
#if defined (SIGTTIN)
|
|
rl_maybe_set_sighandler (SIGTTIN, rl_signal_handler, &old_ttin);
|
|
#endif /* SIGTTIN */
|
|
|
|
signals_set_flag = 1;
|
|
}
|
|
|
|
#if defined (SIGWINCH)
|
|
if (rl_catch_sigwinch && sigwinch_set_flag == 0)
|
|
{
|
|
rl_maybe_set_sighandler (SIGWINCH, rl_sigwinch_handler, &old_winch);
|
|
sigwinch_set_flag = 1;
|
|
}
|
|
#endif /* SIGWINCH */
|
|
|
|
return 0;
|
|
}
|
|
|
|
int
|
|
rl_clear_signals ()
|
|
{
|
|
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);
|
|
rl_sigaction (SIGQUIT, &old_quit, &dummy);
|
|
rl_sigaction (SIGALRM, &old_alrm, &dummy);
|
|
|
|
#if defined (SIGTSTP)
|
|
rl_sigaction (SIGTSTP, &old_tstp, &dummy);
|
|
#endif /* SIGTSTP */
|
|
|
|
#if defined (SIGTTOU)
|
|
rl_sigaction (SIGTTOU, &old_ttou, &dummy);
|
|
#endif /* SIGTTOU */
|
|
|
|
#if defined (SIGTTIN)
|
|
rl_sigaction (SIGTTIN, &old_ttin, &dummy);
|
|
#endif /* SIGTTIN */
|
|
|
|
signals_set_flag = 0;
|
|
}
|
|
|
|
#if defined (SIGWINCH)
|
|
if (rl_catch_sigwinch && sigwinch_set_flag == 1)
|
|
{
|
|
sigemptyset (&dummy.sa_mask);
|
|
rl_sigaction (SIGWINCH, &old_winch, &dummy);
|
|
sigwinch_set_flag = 0;
|
|
}
|
|
#endif
|
|
|
|
return 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_clean_up_for_exit ();
|
|
(*rl_deprep_term_function) ();
|
|
rl_clear_signals ();
|
|
rl_pending_input = 0;
|
|
}
|
|
|
|
/* Reset the terminal and readline state after a signal handler returns. */
|
|
void
|
|
rl_reset_after_signal ()
|
|
{
|
|
(*rl_prep_term_function) (_rl_meta_flag);
|
|
rl_set_signals ();
|
|
}
|
|
|
|
/* Free up the readline variable line state for the current line (undo list,
|
|
any partial history entry, any keyboard macros in progress, and any
|
|
numeric arguments in process) after catching a signal, before calling
|
|
rl_cleanup_after_signal(). */
|
|
void
|
|
rl_free_line_state ()
|
|
{
|
|
register HIST_ENTRY *entry;
|
|
|
|
free_undo_list ();
|
|
|
|
entry = current_history ();
|
|
if (entry)
|
|
entry->data = (char *)NULL;
|
|
|
|
_rl_kill_kbd_macro ();
|
|
rl_clear_message ();
|
|
_rl_init_argument ();
|
|
}
|
|
|
|
#endif /* HANDLE_SIGNALS */
|