1/* Copyright (C) 1991-2004,2007,2009,2010,2012 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Lesser General Public
6 License as published by the Free Software Foundation; either
7 version 2.1 of the License, or (at your option) any later version.
8
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Lesser General Public License for more details.
13
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library; if not, see
16 <http://www.gnu.org/licenses/>. */
17
18/*
19 * ISO C99 Standard: 7.14 Signal handling <signal.h>
20 */
21
22#ifndef _SIGNAL_H
23
24#if !defined __need_sig_atomic_t && !defined __need_sigset_t
25# define _SIGNAL_H
26#endif
27
28#include <features.h>
29
30__BEGIN_DECLS
31
32#include <bits/sigset.h> /* __sigset_t, __sig_atomic_t. */
33
34/* An integral type that can be modified atomically, without the
35 possibility of a signal arriving in the middle of the operation. */
36#if defined __need_sig_atomic_t || defined _SIGNAL_H
37# ifndef __sig_atomic_t_defined
38# define __sig_atomic_t_defined
39__BEGIN_NAMESPACE_STD
40typedef __sig_atomic_t sig_atomic_t;
41__END_NAMESPACE_STD
42# endif
43# undef __need_sig_atomic_t
44#endif
45
46#if defined __need_sigset_t || (defined _SIGNAL_H && defined __USE_POSIX)
47# ifndef __sigset_t_defined
48# define __sigset_t_defined
49typedef __sigset_t sigset_t;
50# endif
51# undef __need_sigset_t
52#endif
53
54#ifdef _SIGNAL_H
55
56#include <bits/types.h>
57#include <bits/signum.h>
58
59#if defined __USE_XOPEN || defined __USE_XOPEN2K
60# ifndef __pid_t_defined
61typedef __pid_t pid_t;
62# define __pid_t_defined
63#endif
64#ifdef __USE_XOPEN
65# endif
66# ifndef __uid_t_defined
67typedef __uid_t uid_t;
68# define __uid_t_defined
69# endif
70#endif /* Unix98 */
71
72#ifdef __USE_POSIX199309
73/* We need `struct timespec' later on. */
74# define __need_timespec
75# include <time.h>
76
77/* Get the `siginfo_t' type plus the needed symbols. */
78# include <bits/siginfo.h>
79#endif
80
81
82/* Type of a signal handler. */
83typedef void (*__sighandler_t) (int);
84
85/* The X/Open definition of `signal' specifies the SVID semantic. Use
86 the additional function `sysv_signal' when X/Open compatibility is
87 requested. */
88extern __sighandler_t __sysv_signal (int __sig, __sighandler_t __handler)
89 __THROW;
90#ifdef __USE_GNU
91extern __sighandler_t sysv_signal (int __sig, __sighandler_t __handler)
92 __THROW;
93#endif
94
95/* Set the handler for the signal SIG to HANDLER, returning the old
96 handler, or SIG_ERR on error.
97 By default `signal' has the BSD semantic. */
98__BEGIN_NAMESPACE_STD
99#ifdef __USE_BSD
100extern __sighandler_t signal (int __sig, __sighandler_t __handler)
101 __THROW;
102#else
103/* Make sure the used `signal' implementation is the SVID version. */
104# ifdef __REDIRECT_NTH
105extern __sighandler_t __REDIRECT_NTH (signal,
106 (int __sig, __sighandler_t __handler),
107 __sysv_signal);
108# else
109# define signal __sysv_signal
110# endif
111#endif
112__END_NAMESPACE_STD
113
114#ifdef __USE_XOPEN
115/* The X/Open definition of `signal' conflicts with the BSD version.
116 So they defined another function `bsd_signal'. */
117extern __sighandler_t bsd_signal (int __sig, __sighandler_t __handler)
118 __THROW;
119#endif
120
121/* Send signal SIG to process number PID. If PID is zero,
122 send SIG to all processes in the current process's process group.
123 If PID is < -1, send SIG to all processes in process group - PID. */
124#ifdef __USE_POSIX
125extern int kill (__pid_t __pid, int __sig) __THROW;
126#endif /* Use POSIX. */
127
128#if defined __USE_BSD || defined __USE_XOPEN_EXTENDED
129/* Send SIG to all processes in process group PGRP.
130 If PGRP is zero, send SIG to all processes in
131 the current process's process group. */
132extern int killpg (__pid_t __pgrp, int __sig) __THROW;
133#endif /* Use BSD || X/Open Unix. */
134
135__BEGIN_NAMESPACE_STD
136/* Raise signal SIG, i.e., send SIG to yourself. */
137extern int raise (int __sig) __THROW;
138__END_NAMESPACE_STD
139
140#ifdef __USE_SVID
141/* SVID names for the same things. */
142extern __sighandler_t ssignal (int __sig, __sighandler_t __handler)
143 __THROW;
144extern int gsignal (int __sig) __THROW;
145#endif /* Use SVID. */
146
147#if defined __USE_MISC || defined __USE_XOPEN2K
148/* Print a message describing the meaning of the given signal number. */
149extern void psignal (int __sig, const char *__s);
150#endif /* Use misc or POSIX 2008. */
151
152#ifdef __USE_XOPEN2K
153/* Print a message describing the meaning of the given signal information. */
154extern void psiginfo (const siginfo_t *__pinfo, const char *__s);
155#endif /* POSIX 2008. */
156
157
158
159/* The `sigpause' function has two different interfaces. The original
160 BSD definition defines the argument as a mask of the signal, while
161 the more modern interface in X/Open defines it as the signal
162 number. We go with the BSD version unless the user explicitly
163 selects the X/Open version.
164
165 This function is a cancellation point and therefore not marked with
166 __THROW. */
167extern int __sigpause (int __sig_or_mask, int __is_sig);
168
169#ifdef __FAVOR_BSD
170/* Set the mask of blocked signals to MASK,
171 wait for a signal to arrive, and then restore the mask. */
172extern int sigpause (int __mask) __THROW __attribute_deprecated__;
173#else
174# ifdef __USE_XOPEN
175# ifdef __GNUC__
176extern int sigpause (int __sig) __asm__ ("__xpg_sigpause");
177# else
178/* Remove a signal from the signal mask and suspend the process. */
179# define sigpause(sig) __sigpause ((sig), 1)
180# endif
181# endif
182#endif
183
184
185#ifdef __USE_BSD
186/* None of the following functions should be used anymore. They are here
187 only for compatibility. A single word (`int') is not guaranteed to be
188 enough to hold a complete signal mask and therefore these functions
189 simply do not work in many situations. Use `sigprocmask' instead. */
190
191/* Compute mask for signal SIG. */
192# define sigmask(sig) __sigmask(sig)
193
194/* Block signals in MASK, returning the old mask. */
195extern int sigblock (int __mask) __THROW __attribute_deprecated__;
196
197/* Set the mask of blocked signals to MASK, returning the old mask. */
198extern int sigsetmask (int __mask) __THROW __attribute_deprecated__;
199
200/* Return currently selected signal mask. */
201extern int siggetmask (void) __THROW __attribute_deprecated__;
202#endif /* Use BSD. */
203
204
205#ifdef __USE_MISC
206# define NSIG _NSIG
207#endif
208
209#ifdef __USE_GNU
210typedef __sighandler_t sighandler_t;
211#endif
212
213/* 4.4 BSD uses the name `sig_t' for this. */
214#ifdef __USE_BSD
215typedef __sighandler_t sig_t;
216#endif
217
218#ifdef __USE_POSIX
219
220/* Clear all signals from SET. */
221extern int sigemptyset (sigset_t *__set) __THROW __nonnull ((1));
222
223/* Set all signals in SET. */
224extern int sigfillset (sigset_t *__set) __THROW __nonnull ((1));
225
226/* Add SIGNO to SET. */
227extern int sigaddset (sigset_t *__set, int __signo) __THROW __nonnull ((1));
228
229/* Remove SIGNO from SET. */
230extern int sigdelset (sigset_t *__set, int __signo) __THROW __nonnull ((1));
231
232/* Return 1 if SIGNO is in SET, 0 if not. */
233extern int sigismember (const sigset_t *__set, int __signo)
234 __THROW __nonnull ((1));
235
236# ifdef __USE_GNU
237/* Return non-empty value is SET is not empty. */
238extern int sigisemptyset (const sigset_t *__set) __THROW __nonnull ((1));
239
240/* Build new signal set by combining the two inputs set using logical AND. */
241extern int sigandset (sigset_t *__set, const sigset_t *__left,
242 const sigset_t *__right) __THROW __nonnull ((1, 2, 3));
243
244/* Build new signal set by combining the two inputs set using logical OR. */
245extern int sigorset (sigset_t *__set, const sigset_t *__left,
246 const sigset_t *__right) __THROW __nonnull ((1, 2, 3));
247# endif /* GNU */
248
249/* Get the system-specific definitions of `struct sigaction'
250 and the `SA_*' and `SIG_*'. constants. */
251# include <bits/sigaction.h>
252
253/* Get and/or change the set of blocked signals. */
254extern int sigprocmask (int __how, const sigset_t *__restrict __set,
255 sigset_t *__restrict __oset) __THROW;
256
257/* Change the set of blocked signals to SET,
258 wait until a signal arrives, and restore the set of blocked signals.
259
260 This function is a cancellation point and therefore not marked with
261 __THROW. */
262extern int sigsuspend (const sigset_t *__set) __nonnull ((1));
263
264/* Get and/or set the action for signal SIG. */
265extern int sigaction (int __sig, const struct sigaction *__restrict __act,
266 struct sigaction *__restrict __oact) __THROW;
267
268/* Put in SET all signals that are blocked and waiting to be delivered. */
269extern int sigpending (sigset_t *__set) __THROW __nonnull ((1));
270
271
272/* Select any of pending signals from SET or wait for any to arrive.
273
274 This function is a cancellation point and therefore not marked with
275 __THROW. */
276extern int sigwait (const sigset_t *__restrict __set, int *__restrict __sig)
277 __nonnull ((1, 2));
278
279# ifdef __USE_POSIX199309
280/* Select any of pending signals from SET and place information in INFO.
281
282 This function is a cancellation point and therefore not marked with
283 __THROW. */
284extern int sigwaitinfo (const sigset_t *__restrict __set,
285 siginfo_t *__restrict __info) __nonnull ((1));
286
287/* Select any of pending signals from SET and place information in INFO.
288 Wait the time specified by TIMEOUT if no signal is pending.
289
290 This function is a cancellation point and therefore not marked with
291 __THROW. */
292extern int sigtimedwait (const sigset_t *__restrict __set,
293 siginfo_t *__restrict __info,
294 const struct timespec *__restrict __timeout)
295 __nonnull ((1));
296
297/* Send signal SIG to the process PID. Associate data in VAL with the
298 signal. */
299extern int sigqueue (__pid_t __pid, int __sig, const union sigval __val)
300 __THROW;
301# endif /* Use POSIX 199306. */
302
303#endif /* Use POSIX. */
304
305#ifdef __USE_BSD
306
307/* Names of the signals. This variable exists only for compatibility.
308 Use `strsignal' instead (see <string.h>). */
309extern const char *const _sys_siglist[_NSIG];
310extern const char *const sys_siglist[_NSIG];
311
312/* Structure passed to `sigvec'. */
313struct sigvec
314 {
315 __sighandler_t sv_handler; /* Signal handler. */
316 int sv_mask; /* Mask of signals to be blocked. */
317
318 int sv_flags; /* Flags (see below). */
319# define sv_onstack sv_flags /* 4.2 BSD compatibility. */
320 };
321
322/* Bits in `sv_flags'. */
323# define SV_ONSTACK (1 << 0)/* Take the signal on the signal stack. */
324# define SV_INTERRUPT (1 << 1)/* Do not restart system calls. */
325# define SV_RESETHAND (1 << 2)/* Reset handler to SIG_DFL on receipt. */
326
327
328/* If VEC is non-NULL, set the handler for SIG to the `sv_handler' member
329 of VEC. The signals in `sv_mask' will be blocked while the handler runs.
330 If the SV_RESETHAND bit is set in `sv_flags', the handler for SIG will be
331 reset to SIG_DFL before `sv_handler' is entered. If OVEC is non-NULL,
332 it is filled in with the old information for SIG. */
333extern int sigvec (int __sig, const struct sigvec *__vec,
334 struct sigvec *__ovec) __THROW;
335
336
337/* Get machine-dependent `struct sigcontext' and signal subcodes. */
338# include <bits/sigcontext.h>
339
340/* Restore the state saved in SCP. */
341extern int sigreturn (struct sigcontext *__scp) __THROW;
342
343#endif /* use BSD. */
344
345
346#if defined __USE_BSD || defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K8
347# define __need_size_t
348# include <stddef.h>
349
350/* If INTERRUPT is nonzero, make signal SIG interrupt system calls
351 (causing them to fail with EINTR); if INTERRUPT is zero, make system
352 calls be restarted after signal SIG. */
353extern int siginterrupt (int __sig, int __interrupt) __THROW;
354
355# include <bits/sigstack.h>
356# if defined __USE_XOPEN || defined __USE_XOPEN2K8
357/* This will define `ucontext_t' and `mcontext_t'. */
358# include <sys/ucontext.h>
359# endif
360
361/* Run signals handlers on the stack specified by SS (if not NULL).
362 If OSS is not NULL, it is filled in with the old signal stack status.
363 This interface is obsolete and on many platform not implemented. */
364extern int sigstack (struct sigstack *__ss, struct sigstack *__oss)
365 __THROW __attribute_deprecated__;
366
367/* Alternate signal handler stack interface.
368 This interface should always be preferred over `sigstack'. */
369extern int sigaltstack (const struct sigaltstack *__restrict __ss,
370 struct sigaltstack *__restrict __oss) __THROW;
371
372#endif /* use BSD or X/Open Unix. */
373
374#ifdef __USE_XOPEN_EXTENDED
375/* Simplified interface for signal management. */
376
377/* Add SIG to the calling process' signal mask. */
378extern int sighold (int __sig) __THROW;
379
380/* Remove SIG from the calling process' signal mask. */
381extern int sigrelse (int __sig) __THROW;
382
383/* Set the disposition of SIG to SIG_IGN. */
384extern int sigignore (int __sig) __THROW;
385
386/* Set the disposition of SIG. */
387extern __sighandler_t sigset (int __sig, __sighandler_t __disp) __THROW;
388#endif
389
390#if defined __USE_POSIX199506 || defined __USE_UNIX98
391/* Some of the functions for handling signals in threaded programs must
392 be defined here. */
393# include <bits/pthreadtypes.h>
394# include <bits/sigthread.h>
395#endif /* use Unix98 */
396
397/* The following functions are used internally in the C library and in
398 other code which need deep insights. */
399
400/* Return number of available real-time signal with highest priority. */
401extern int __libc_current_sigrtmin (void) __THROW;
402/* Return number of available real-time signal with lowest priority. */
403extern int __libc_current_sigrtmax (void) __THROW;
404
405#endif /* signal.h */
406
407__END_DECLS
408
409#endif /* not signal.h */
410