1/* Copyright (C) 1991-2014 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#endif
77
78#if defined __USE_POSIX199309 || defined __USE_XOPEN_EXTENDED
79/* Get the `siginfo_t' type plus the needed symbols. */
80# include <bits/siginfo.h>
81#endif
82
83
84/* Type of a signal handler. */
85typedef void (*__sighandler_t) (int);
86
87/* The X/Open definition of `signal' specifies the SVID semantic. Use
88 the additional function `sysv_signal' when X/Open compatibility is
89 requested. */
90extern __sighandler_t __sysv_signal (int __sig, __sighandler_t __handler)
91 __THROW;
92#ifdef __USE_GNU
93extern __sighandler_t sysv_signal (int __sig, __sighandler_t __handler)
94 __THROW;
95#endif
96
97/* Set the handler for the signal SIG to HANDLER, returning the old
98 handler, or SIG_ERR on error.
99 By default `signal' has the BSD semantic. */
100__BEGIN_NAMESPACE_STD
101#ifdef __USE_BSD
102extern __sighandler_t signal (int __sig, __sighandler_t __handler)
103 __THROW;
104#else
105/* Make sure the used `signal' implementation is the SVID version. */
106# ifdef __REDIRECT_NTH
107extern __sighandler_t __REDIRECT_NTH (signal,
108 (int __sig, __sighandler_t __handler),
109 __sysv_signal);
110# else
111# define signal __sysv_signal
112# endif
113#endif
114__END_NAMESPACE_STD
115
116#ifdef __USE_XOPEN
117/* The X/Open definition of `signal' conflicts with the BSD version.
118 So they defined another function `bsd_signal'. */
119extern __sighandler_t bsd_signal (int __sig, __sighandler_t __handler)
120 __THROW;
121#endif
122
123/* Send signal SIG to process number PID. If PID is zero,
124 send SIG to all processes in the current process's process group.
125 If PID is < -1, send SIG to all processes in process group - PID. */
126#ifdef __USE_POSIX
127extern int kill (__pid_t __pid, int __sig) __THROW;
128#endif /* Use POSIX. */
129
130#if defined __USE_BSD || defined __USE_XOPEN_EXTENDED
131/* Send SIG to all processes in process group PGRP.
132 If PGRP is zero, send SIG to all processes in
133 the current process's process group. */
134extern int killpg (__pid_t __pgrp, int __sig) __THROW;
135#endif /* Use BSD || X/Open Unix. */
136
137__BEGIN_NAMESPACE_STD
138/* Raise signal SIG, i.e., send SIG to yourself. */
139extern int raise (int __sig) __THROW;
140__END_NAMESPACE_STD
141
142#ifdef __USE_SVID
143/* SVID names for the same things. */
144extern __sighandler_t ssignal (int __sig, __sighandler_t __handler)
145 __THROW;
146extern int gsignal (int __sig) __THROW;
147#endif /* Use SVID. */
148
149#if defined __USE_MISC || defined __USE_XOPEN2K
150/* Print a message describing the meaning of the given signal number. */
151extern void psignal (int __sig, const char *__s);
152#endif /* Use misc or POSIX 2008. */
153
154#ifdef __USE_XOPEN2K
155/* Print a message describing the meaning of the given signal information. */
156extern void psiginfo (const siginfo_t *__pinfo, const char *__s);
157#endif /* POSIX 2008. */
158
159
160
161/* The `sigpause' function in X/Open defines the argument as the
162 signal number. This requires redirecting to another function
163 because the default version in glibc uses an old BSD interface.
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 __USE_XOPEN
170# ifdef __GNUC__
171extern int sigpause (int __sig) __asm__ ("__xpg_sigpause");
172# else
173/* Remove a signal from the signal mask and suspend the process. */
174# define sigpause(sig) __sigpause ((sig), 1)
175# endif
176#endif
177
178
179#ifdef __USE_BSD
180/* None of the following functions should be used anymore. They are here
181 only for compatibility. A single word (`int') is not guaranteed to be
182 enough to hold a complete signal mask and therefore these functions
183 simply do not work in many situations. Use `sigprocmask' instead. */
184
185/* Compute mask for signal SIG. */
186# define sigmask(sig) __sigmask(sig)
187
188/* Block signals in MASK, returning the old mask. */
189extern int sigblock (int __mask) __THROW __attribute_deprecated__;
190
191/* Set the mask of blocked signals to MASK, returning the old mask. */
192extern int sigsetmask (int __mask) __THROW __attribute_deprecated__;
193
194/* Return currently selected signal mask. */
195extern int siggetmask (void) __THROW __attribute_deprecated__;
196#endif /* Use BSD. */
197
198
199#ifdef __USE_MISC
200# define NSIG _NSIG
201#endif
202
203#ifdef __USE_GNU
204typedef __sighandler_t sighandler_t;
205#endif
206
207/* 4.4 BSD uses the name `sig_t' for this. */
208#ifdef __USE_BSD
209typedef __sighandler_t sig_t;
210#endif
211
212#ifdef __USE_POSIX
213
214/* Clear all signals from SET. */
215extern int sigemptyset (sigset_t *__set) __THROW __nonnull ((1));
216
217/* Set all signals in SET. */
218extern int sigfillset (sigset_t *__set) __THROW __nonnull ((1));
219
220/* Add SIGNO to SET. */
221extern int sigaddset (sigset_t *__set, int __signo) __THROW __nonnull ((1));
222
223/* Remove SIGNO from SET. */
224extern int sigdelset (sigset_t *__set, int __signo) __THROW __nonnull ((1));
225
226/* Return 1 if SIGNO is in SET, 0 if not. */
227extern int sigismember (const sigset_t *__set, int __signo)
228 __THROW __nonnull ((1));
229
230# ifdef __USE_GNU
231/* Return non-empty value is SET is not empty. */
232extern int sigisemptyset (const sigset_t *__set) __THROW __nonnull ((1));
233
234/* Build new signal set by combining the two inputs set using logical AND. */
235extern int sigandset (sigset_t *__set, const sigset_t *__left,
236 const sigset_t *__right) __THROW __nonnull ((1, 2, 3));
237
238/* Build new signal set by combining the two inputs set using logical OR. */
239extern int sigorset (sigset_t *__set, const sigset_t *__left,
240 const sigset_t *__right) __THROW __nonnull ((1, 2, 3));
241# endif /* GNU */
242
243/* Get the system-specific definitions of `struct sigaction'
244 and the `SA_*' and `SIG_*'. constants. */
245# include <bits/sigaction.h>
246
247/* Get and/or change the set of blocked signals. */
248extern int sigprocmask (int __how, const sigset_t *__restrict __set,
249 sigset_t *__restrict __oset) __THROW;
250
251/* Change the set of blocked signals to SET,
252 wait until a signal arrives, and restore the set of blocked signals.
253
254 This function is a cancellation point and therefore not marked with
255 __THROW. */
256extern int sigsuspend (const sigset_t *__set) __nonnull ((1));
257
258/* Get and/or set the action for signal SIG. */
259extern int sigaction (int __sig, const struct sigaction *__restrict __act,
260 struct sigaction *__restrict __oact) __THROW;
261
262/* Put in SET all signals that are blocked and waiting to be delivered. */
263extern int sigpending (sigset_t *__set) __THROW __nonnull ((1));
264
265
266/* Select any of pending signals from SET or wait for any to arrive.
267
268 This function is a cancellation point and therefore not marked with
269 __THROW. */
270extern int sigwait (const sigset_t *__restrict __set, int *__restrict __sig)
271 __nonnull ((1, 2));
272
273# ifdef __USE_POSIX199309
274/* Select any of pending signals from SET and place information in INFO.
275
276 This function is a cancellation point and therefore not marked with
277 __THROW. */
278extern int sigwaitinfo (const sigset_t *__restrict __set,
279 siginfo_t *__restrict __info) __nonnull ((1));
280
281/* Select any of pending signals from SET and place information in INFO.
282 Wait the time specified by TIMEOUT if no signal is pending.
283
284 This function is a cancellation point and therefore not marked with
285 __THROW. */
286extern int sigtimedwait (const sigset_t *__restrict __set,
287 siginfo_t *__restrict __info,
288 const struct timespec *__restrict __timeout)
289 __nonnull ((1));
290
291/* Send signal SIG to the process PID. Associate data in VAL with the
292 signal. */
293extern int sigqueue (__pid_t __pid, int __sig, const union sigval __val)
294 __THROW;
295# endif /* Use POSIX 199306. */
296
297#endif /* Use POSIX. */
298
299#ifdef __USE_BSD
300
301/* Names of the signals. This variable exists only for compatibility.
302 Use `strsignal' instead (see <string.h>). */
303extern const char *const _sys_siglist[_NSIG];
304extern const char *const sys_siglist[_NSIG];
305
306/* Structure passed to `sigvec'. */
307struct sigvec
308 {
309 __sighandler_t sv_handler; /* Signal handler. */
310 int sv_mask; /* Mask of signals to be blocked. */
311
312 int sv_flags; /* Flags (see below). */
313# define sv_onstack sv_flags /* 4.2 BSD compatibility. */
314 };
315
316/* Bits in `sv_flags'. */
317# define SV_ONSTACK (1 << 0)/* Take the signal on the signal stack. */
318# define SV_INTERRUPT (1 << 1)/* Do not restart system calls. */
319# define SV_RESETHAND (1 << 2)/* Reset handler to SIG_DFL on receipt. */
320
321
322/* If VEC is non-NULL, set the handler for SIG to the `sv_handler' member
323 of VEC. The signals in `sv_mask' will be blocked while the handler runs.
324 If the SV_RESETHAND bit is set in `sv_flags', the handler for SIG will be
325 reset to SIG_DFL before `sv_handler' is entered. If OVEC is non-NULL,
326 it is filled in with the old information for SIG. */
327extern int sigvec (int __sig, const struct sigvec *__vec,
328 struct sigvec *__ovec) __THROW;
329
330
331/* Get machine-dependent `struct sigcontext' and signal subcodes. */
332# include <bits/sigcontext.h>
333
334/* Restore the state saved in SCP. */
335extern int sigreturn (struct sigcontext *__scp) __THROW;
336
337#endif /* use BSD. */
338
339
340#if defined __USE_BSD || defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K8
341# define __need_size_t
342# include <stddef.h>
343
344/* If INTERRUPT is nonzero, make signal SIG interrupt system calls
345 (causing them to fail with EINTR); if INTERRUPT is zero, make system
346 calls be restarted after signal SIG. */
347extern int siginterrupt (int __sig, int __interrupt) __THROW;
348
349# include <bits/sigstack.h>
350# if defined __USE_XOPEN || defined __USE_XOPEN2K8
351/* This will define `ucontext_t' and `mcontext_t'. */
352# include <sys/ucontext.h>
353# endif
354
355/* Run signals handlers on the stack specified by SS (if not NULL).
356 If OSS is not NULL, it is filled in with the old signal stack status.
357 This interface is obsolete and on many platform not implemented. */
358extern int sigstack (struct sigstack *__ss, struct sigstack *__oss)
359 __THROW __attribute_deprecated__;
360
361/* Alternate signal handler stack interface.
362 This interface should always be preferred over `sigstack'. */
363extern int sigaltstack (const struct sigaltstack *__restrict __ss,
364 struct sigaltstack *__restrict __oss) __THROW;
365
366#endif /* use BSD or X/Open Unix. */
367
368#ifdef __USE_XOPEN_EXTENDED
369/* Simplified interface for signal management. */
370
371/* Add SIG to the calling process' signal mask. */
372extern int sighold (int __sig) __THROW;
373
374/* Remove SIG from the calling process' signal mask. */
375extern int sigrelse (int __sig) __THROW;
376
377/* Set the disposition of SIG to SIG_IGN. */
378extern int sigignore (int __sig) __THROW;
379
380/* Set the disposition of SIG. */
381extern __sighandler_t sigset (int __sig, __sighandler_t __disp) __THROW;
382#endif
383
384#if defined __USE_POSIX199506 || defined __USE_UNIX98
385/* Some of the functions for handling signals in threaded programs must
386 be defined here. */
387# include <bits/pthreadtypes.h>
388# include <bits/sigthread.h>
389#endif /* use Unix98 */
390
391/* The following functions are used internally in the C library and in
392 other code which need deep insights. */
393
394/* Return number of available real-time signal with highest priority. */
395extern int __libc_current_sigrtmin (void) __THROW;
396/* Return number of available real-time signal with lowest priority. */
397extern int __libc_current_sigrtmax (void) __THROW;
398
399#endif /* signal.h */
400
401__END_DECLS
402
403#endif /* not signal.h */
404