1
/* signals.c -- signal handling support for readline. */
3
/* Copyright (C) 1987, 1989, 1992 Free Software Foundation, Inc.
5
This file is part of the GNU Readline Library, a library for
6
reading lines of text with interactive input and history editing.
8
The GNU Readline Library is free software; you can redistribute it
9
and/or modify it under the terms of the GNU General Public License
10
as published by the Free Software Foundation; either version 1, or
11
(at your option) any later version.
13
The GNU Readline Library is distributed in the hope that it will be
14
useful, but WITHOUT ANY WARRANTY; without even the implied warranty
15
of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16
GNU General Public License for more details.
18
The GNU General Public License is often shipped with GNU software, and
19
is generally kept in a file called COPYING or LICENSE. If you do not
20
have a copy of the license, write to the Free Software Foundation,
21
675 Mass Ave, Cambridge, MA 02139, USA. */
22
#define READLINE_LIBRARY
24
#if defined (HAVE_CONFIG_H)
28
#include <stdio.h> /* Just for NULL. Yuck. */
29
#include <sys/types.h>
32
#if defined (HAVE_UNISTD_H)
34
#endif /* HAVE_UNISTD_H */
36
/* System-specific feature definitions and include files. */
39
#if defined (GWINSZ_IN_SYS_IOCTL)
40
# include <sys/ioctl.h>
41
#endif /* GWINSZ_IN_SYS_IOCTL */
43
#if defined (__GO32__)
44
# undef HANDLE_SIGNALS
47
#if defined (HANDLE_SIGNALS)
48
/* Some standard library routines. */
52
#if !defined (RETSIGTYPE)
53
# if defined (VOID_SIGHANDLER)
54
# define RETSIGTYPE void
56
# define RETSIGTYPE int
57
# endif /* !VOID_SIGHANDLER */
58
#endif /* !RETSIGTYPE */
60
#if defined (VOID_SIGHANDLER)
61
# define SIGHANDLER_RETURN return
63
# define SIGHANDLER_RETURN return (0)
66
/* This typedef is equivalant to the one for Function; it allows us
67
to say SigHandler *foo = signal (SIGKILL, SIG_IGN); */
68
typedef RETSIGTYPE SigHandler ();
70
extern int readline_echoing_p;
71
extern int rl_pending_input;
72
extern int _rl_meta_flag;
74
extern void free_undo_list ();
75
extern void _rl_get_screen_size ();
76
extern void _rl_redisplay_after_sigwinch ();
77
extern void _rl_clean_up_for_exit ();
78
extern void _rl_kill_kbd_macro ();
79
extern void _rl_init_argument ();
80
extern void rl_deprep_terminal (), rl_prep_terminal ();
82
static SigHandler *rl_set_sighandler ();
84
/* Exported variables for use by applications. */
86
/* If non-zero, readline will install its own signal handlers for
87
SIGINT, SIGTERM, SIGQUIT, SIGALRM, SIGTSTP, SIGTTIN, and SIGTTOU. */
88
int rl_catch_signals = 1;
90
/* If non-zero, readline will install a signal handler for SIGWINCH. */
92
int rl_catch_sigwinch = 1;
95
static int signals_set_flag;
96
static int sigwinch_set_flag;
98
/* **************************************************************** */
100
/* Signal Handling */
102
/* **************************************************************** */
104
#if defined (HAVE_POSIX_SIGNALS)
105
typedef struct sigaction sighandler_cxt;
106
# define rl_sigaction(s, nh, oh) sigaction(s, nh, oh)
108
typedef struct { SigHandler *sa_handler; int sa_mask, sa_flags; } sighandler_cxt;
109
# define sigemptyset(m)
110
#endif /* !HAVE_POSIX_SIGNALS */
112
static sighandler_cxt old_int, old_term, old_alrm, old_quit;
113
#if defined (SIGTSTP)
114
static sighandler_cxt old_tstp, old_ttou, old_ttin;
116
#if defined (SIGWINCH)
117
static sighandler_cxt old_winch;
120
/* Readline signal handler functions. */
123
rl_signal_handler (sig)
126
#if defined (HAVE_POSIX_SIGNALS)
128
#else /* !HAVE_POSIX_SIGNALS */
129
# if defined (HAVE_BSD_SIGNALS)
131
# else /* !HAVE_BSD_SIGNALS */
132
sighandler_cxt dummy_cxt; /* needed for rl_set_sighandler call */
133
# endif /* !HAVE_BSD_SIGNALS */
134
#endif /* !HAVE_POSIX_SIGNALS */
136
#if !defined (HAVE_BSD_SIGNALS) && !defined (HAVE_POSIX_SIGNALS)
137
/* Since the signal will not be blocked while we are in the signal
138
handler, ignore it until rl_clear_signals resets the catcher. */
139
if (sig == SIGINT || sig == SIGALRM)
140
rl_set_sighandler (sig, SIG_IGN, &dummy_cxt);
141
#endif /* !HAVE_BSD_SIGNALS && !HAVE_POSIX_SIGNALS */
146
rl_free_line_state ();
149
#if defined (SIGTSTP)
157
rl_cleanup_after_signal ();
159
#if defined (HAVE_POSIX_SIGNALS)
160
sigprocmask (SIG_BLOCK, (sigset_t *)NULL, &set);
161
sigdelset (&set, sig);
162
#else /* !HAVE_POSIX_SIGNALS */
163
# if defined (HAVE_BSD_SIGNALS)
164
omask = sigblock (0);
165
# endif /* HAVE_BSD_SIGNALS */
166
#endif /* !HAVE_POSIX_SIGNALS */
168
kill (getpid (), sig);
170
/* Let the signal that we just sent through. */
171
#if defined (HAVE_POSIX_SIGNALS)
172
sigprocmask (SIG_SETMASK, &set, (sigset_t *)NULL);
173
#else /* !HAVE_POSIX_SIGNALS */
174
# if defined (HAVE_BSD_SIGNALS)
175
sigsetmask (omask & ~(sigmask (sig)));
176
# endif /* HAVE_BSD_SIGNALS */
177
#endif /* !HAVE_POSIX_SIGNALS */
179
rl_reset_after_signal ();
185
#if defined (SIGWINCH)
187
rl_sigwinch_handler (sig)
192
#if defined (MUST_REINSTALL_SIGHANDLERS)
193
sighandler_cxt dummy_winch;
195
/* We don't want to change old_winch -- it holds the state of SIGWINCH
196
disposition set by the calling application. We need this state
197
because we call the application's SIGWINCH handler after updating
198
our own idea of the screen size. */
199
rl_set_sighandler (SIGWINCH, rl_sigwinch_handler, &dummy_winch);
202
rl_resize_terminal ();
204
/* If another sigwinch handler has been installed, call it. */
205
oh = (SigHandler *)old_winch.sa_handler;
206
if (oh && oh != (SigHandler *)SIG_IGN && oh != (SigHandler *)SIG_DFL)
211
#endif /* SIGWINCH */
213
/* Functions to manage signal handling. */
215
#if !defined (HAVE_POSIX_SIGNALS)
217
rl_sigaction (sig, nh, oh)
219
sighandler_cxt *nh, *oh;
221
oh->sa_handler = signal (sig, nh->sa_handler);
224
#endif /* !HAVE_POSIX_SIGNALS */
226
/* Set up a readline-specific signal handler, saving the old signal
227
information in OHANDLER. Return the old signal handler, like
230
rl_set_sighandler (sig, handler, ohandler)
233
sighandler_cxt *ohandler;
235
#if defined (HAVE_POSIX_SIGNALS)
236
struct sigaction act;
238
act.sa_handler = handler;
240
sigemptyset (&act.sa_mask);
241
sigemptyset (&ohandler->sa_mask);
242
sigaction (sig, &act, ohandler);
244
ohandler->sa_handler = (SigHandler *)signal (sig, handler);
245
#endif /* !HAVE_POSIX_SIGNALS */
246
return (ohandler->sa_handler);
250
rl_maybe_set_sighandler (sig, handler, ohandler)
253
sighandler_cxt *ohandler;
255
sighandler_cxt dummy;
258
sigemptyset (&dummy.sa_mask);
259
oh = rl_set_sighandler (sig, handler, ohandler);
260
if (oh == (SigHandler *)SIG_IGN)
261
rl_sigaction (sig, ohandler, &dummy);
267
sighandler_cxt dummy;
270
if (rl_catch_signals && signals_set_flag == 0)
272
rl_maybe_set_sighandler (SIGINT, rl_signal_handler, &old_int);
273
rl_maybe_set_sighandler (SIGTERM, rl_signal_handler, &old_term);
274
rl_maybe_set_sighandler (SIGQUIT, rl_signal_handler, &old_quit);
276
oh = rl_set_sighandler (SIGALRM, rl_signal_handler, &old_alrm);
277
if (oh == (SigHandler *)SIG_IGN)
278
rl_sigaction (SIGALRM, &old_alrm, &dummy);
279
#if defined (HAVE_POSIX_SIGNALS) && defined (SA_RESTART)
280
/* If the application using readline has already installed a signal
281
handler with SA_RESTART, SIGALRM will cause reads to be restarted
282
automatically, so readline should just get out of the way. Since
283
we tested for SIG_IGN above, we can just test for SIG_DFL here. */
284
if (oh != (SigHandler *)SIG_DFL && (old_alrm.sa_flags & SA_RESTART))
285
rl_sigaction (SIGALRM, &old_alrm, &dummy);
286
#endif /* HAVE_POSIX_SIGNALS */
288
#if defined (SIGTSTP)
289
rl_maybe_set_sighandler (SIGTSTP, rl_signal_handler, &old_tstp);
292
#if defined (SIGTTOU)
293
rl_maybe_set_sighandler (SIGTTOU, rl_signal_handler, &old_ttou);
296
#if defined (SIGTTIN)
297
rl_maybe_set_sighandler (SIGTTIN, rl_signal_handler, &old_ttin);
300
signals_set_flag = 1;
303
#if defined (SIGWINCH)
304
if (rl_catch_sigwinch && sigwinch_set_flag == 0)
306
rl_maybe_set_sighandler (SIGWINCH, rl_sigwinch_handler, &old_winch);
307
sigwinch_set_flag = 1;
309
#endif /* SIGWINCH */
317
sighandler_cxt dummy;
319
if (rl_catch_signals && signals_set_flag == 1)
321
sigemptyset (&dummy.sa_mask);
323
rl_sigaction (SIGINT, &old_int, &dummy);
324
rl_sigaction (SIGTERM, &old_term, &dummy);
325
rl_sigaction (SIGQUIT, &old_quit, &dummy);
326
rl_sigaction (SIGALRM, &old_alrm, &dummy);
328
#if defined (SIGTSTP)
329
rl_sigaction (SIGTSTP, &old_tstp, &dummy);
332
#if defined (SIGTTOU)
333
rl_sigaction (SIGTTOU, &old_ttou, &dummy);
336
#if defined (SIGTTIN)
337
rl_sigaction (SIGTTIN, &old_ttin, &dummy);
340
signals_set_flag = 0;
343
#if defined (SIGWINCH)
344
if (rl_catch_sigwinch && sigwinch_set_flag == 1)
346
sigemptyset (&dummy.sa_mask);
347
rl_sigaction (SIGWINCH, &old_winch, &dummy);
348
sigwinch_set_flag = 0;
355
/* Clean up the terminal and readline state after catching a signal, before
356
resending it to the calling application. */
358
rl_cleanup_after_signal ()
360
_rl_clean_up_for_exit ();
361
(*rl_deprep_term_function) ();
363
rl_pending_input = 0;
366
/* Reset the terminal and readline state after a signal handler returns. */
368
rl_reset_after_signal ()
370
(*rl_prep_term_function) (_rl_meta_flag);
374
/* Free up the readline variable line state for the current line (undo list,
375
any partial history entry, any keyboard macros in progress, and any
376
numeric arguments in process) after catching a signal, before calling
377
rl_cleanup_after_signal(). */
379
rl_free_line_state ()
381
register HIST_ENTRY *entry;
385
entry = current_history ();
387
entry->data = (char *)NULL;
389
_rl_kill_kbd_macro ();
391
_rl_init_argument ();
394
#endif /* HANDLE_SIGNALS */
added
removed
readline-4.0/signals.c
