1/* Copyright (C) 1991-2022 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 <https://www.gnu.org/licenses/>. */ 
17 
18/* 
19 * ISO C99 Standard: 7.14 Signal handling <signal.h> 
20 */ 
21 
22#ifndef _SIGNAL_H 
23#define _SIGNAL_H 
24 
25#include <features.h> 
26 
27__BEGIN_DECLS 
28 
29#include <bits/types.h> 
30#include <bits/signum-generic.h> 
31 
32#include <bits/types/sig_atomic_t.h> 
33 
34#if defined __USE_POSIX 
35#include <bits/types/sigset_t.h> 
36#endif 
37 
38#if defined __USE_XOPEN || defined __USE_XOPEN2K 
39# ifndef __pid_t_defined 
40typedef __pid_t pid_t; 
41# define __pid_t_defined 
42#endif 
43#ifdef __USE_XOPEN 
44# endif 
45# ifndef __uid_t_defined 
46typedef __uid_t uid_t; 
47# define __uid_t_defined 
48# endif 
49#endif /* Unix98 */ 
50 
51#ifdef __USE_POSIX199309 
52/* We need `struct timespec' later on. */ 
53# include <bits/types/struct_timespec.h> 
54#endif 
55 
56#if defined __USE_POSIX199309 || defined __USE_XOPEN_EXTENDED 
57# include <bits/types/siginfo_t.h> 
58# include <bits/siginfo-consts.h> 
59#endif 
60 
61#ifdef __USE_MISC 
62# include <bits/types/sigval_t.h> 
63#endif 
64 
65#ifdef __USE_POSIX199309 
66# include <bits/types/sigevent_t.h> 
67# include <bits/sigevent-consts.h> 
68#endif 
69 
70 
71/* Type of a signal handler. */ 
72typedef void (*__sighandler_t) (int); 
73 
74/* The X/Open definition of `signal' specifies the SVID semantic. Use 
75 the additional function `sysv_signal' when X/Open compatibility is 
76 requested. */ 
77extern __sighandler_t __sysv_signal (int __sig, __sighandler_t __handler) 
78 __THROW; 
79#ifdef __USE_GNU 
80extern __sighandler_t sysv_signal (int __sig, __sighandler_t __handler) 
81 __THROW; 
82#endif 
83 
84/* Set the handler for the signal SIG to HANDLER, returning the old 
85 handler, or SIG_ERR on error. 
86 By default `signal' has the BSD semantic. */ 
87#ifdef __USE_MISC 
88extern __sighandler_t signal (int __sig, __sighandler_t __handler) 
89 __THROW; 
90#else 
91/* Make sure the used `signal' implementation is the SVID version. */ 
92# ifdef __REDIRECT_NTH 
93extern __sighandler_t __REDIRECT_NTH (signal, 
94 (int __sig, __sighandler_t __handler), 
95 __sysv_signal); 
96# else 
97# define signal __sysv_signal 
98# endif 
99#endif 
100 
101#if defined __USE_XOPEN_EXTENDED && !defined __USE_XOPEN2K8 
102/* The X/Open definition of `signal' conflicts with the BSD version. 
103 So they defined another function `bsd_signal'. */ 
104extern __sighandler_t bsd_signal (int __sig, __sighandler_t __handler) 
105 __THROW; 
106#endif 
107 
108/* Send signal SIG to process number PID. If PID is zero, 
109 send SIG to all processes in the current process's process group. 
110 If PID is < -1, send SIG to all processes in process group - PID. */ 
111#ifdef __USE_POSIX 
112extern int kill (__pid_t __pid, int __sig) __THROW; 
113#endif /* Use POSIX. */ 
114 
115#if defined __USE_MISC || defined __USE_XOPEN_EXTENDED 
116/* Send SIG to all processes in process group PGRP. 
117 If PGRP is zero, send SIG to all processes in 
118 the current process's process group. */ 
119extern int killpg (__pid_t __pgrp, int __sig) __THROW; 
120#endif /* Use misc || X/Open Unix. */ 
121 
122/* Raise signal SIG, i.e., send SIG to yourself. */ 
123extern int raise (int __sig) __THROW; 
124 
125#ifdef __USE_MISC 
126/* SVID names for the same things. */ 
127extern __sighandler_t ssignal (int __sig, __sighandler_t __handler) 
128 __THROW; 
129extern int gsignal (int __sig) __THROW; 
130#endif /* Use misc. */ 
131 
132#ifdef __USE_XOPEN2K8 
133/* Print a message describing the meaning of the given signal number. */ 
134extern void psignal (int __sig, const char *__s); 
135 
136/* Print a message describing the meaning of the given signal information. */ 
137extern void psiginfo (const siginfo_t *__pinfo, const char *__s); 
138#endif /* POSIX 2008. */ 
139 
140 
141 
142/* The `sigpause' function in X/Open defines the argument as the 
143 signal number. This requires redirecting to another function 
144 because the default version in glibc uses an old BSD interface. 
145 
146 This function is a cancellation point and therefore not marked with 
147 __THROW. */ 
148 
149#ifdef __USE_XOPEN_EXTENDED 
150# ifdef __GNUC__ 
151extern int sigpause (int __sig) __asm__ ("__xpg_sigpause") 
152 __attribute_deprecated_msg__ ("Use the sigsuspend function instead"); 
153# else 
154extern int __sigpause (int __sig_or_mask, int __is_sig); 
155/* Remove a signal from the signal mask and suspend the process. */ 
156# define sigpause(sig) __sigpause ((sig), 1) 
157# endif 
158#endif 
159 
160 
161#ifdef __USE_MISC 
162/* None of the following functions should be used anymore. They are here 
163 only for compatibility. A single word (`int') is not guaranteed to be 
164 enough to hold a complete signal mask and therefore these functions 
165 simply do not work in many situations. Use `sigprocmask' instead. */ 
166 
167/* Compute mask for signal SIG. */ 
168# define sigmask(sig) \ 
169 __glibc_macro_warning ("sigmask is deprecated") \ 
170 ((int)(1u << ((sig) - 1))) 
171 
172/* Block signals in MASK, returning the old mask. */ 
173extern int sigblock (int __mask) __THROW __attribute_deprecated__; 
174 
175/* Set the mask of blocked signals to MASK, returning the old mask. */ 
176extern int sigsetmask (int __mask) __THROW __attribute_deprecated__; 
177 
178/* Return currently selected signal mask. */ 
179extern int siggetmask (void) __THROW __attribute_deprecated__; 
180#endif /* Use misc. */ 
181 
182 
183#ifdef __USE_MISC 
184# define NSIG _NSIG 
185#endif 
186 
187#ifdef __USE_GNU 
188typedef __sighandler_t sighandler_t; 
189#endif 
190 
191/* 4.4 BSD uses the name `sig_t' for this. */ 
192#ifdef __USE_MISC 
193typedef __sighandler_t sig_t; 
194#endif 
195 
196#ifdef __USE_POSIX 
197 
198/* Clear all signals from SET. */ 
199extern int sigemptyset (sigset_t *__set) __THROW __nonnull ((1)); 
200 
201/* Set all signals in SET. */ 
202extern int sigfillset (sigset_t *__set) __THROW __nonnull ((1)); 
203 
204/* Add SIGNO to SET. */ 
205extern int sigaddset (sigset_t *__set, int __signo) __THROW __nonnull ((1)); 
206 
207/* Remove SIGNO from SET. */ 
208extern int sigdelset (sigset_t *__set, int __signo) __THROW __nonnull ((1)); 
209 
210/* Return 1 if SIGNO is in SET, 0 if not. */ 
211extern int sigismember (const sigset_t *__set, int __signo) 
212 __THROW __nonnull ((1)); 
213 
214# ifdef __USE_GNU 
215/* Return non-empty value is SET is not empty. */ 
216extern int sigisemptyset (const sigset_t *__set) __THROW __nonnull ((1)); 
217 
218/* Build new signal set by combining the two inputs set using logical AND. */ 
219extern int sigandset (sigset_t *__set, const sigset_t *__left, 
220 const sigset_t *__right) __THROW __nonnull ((1, 2, 3)); 
221 
222/* Build new signal set by combining the two inputs set using logical OR. */ 
223extern int sigorset (sigset_t *__set, const sigset_t *__left, 
224 const sigset_t *__right) __THROW __nonnull ((1, 2, 3)); 
225# endif /* GNU */ 
226 
227/* Get the system-specific definitions of `struct sigaction' 
228 and the `SA_*' and `SIG_*'. constants. */ 
229# include <bits/sigaction.h> 
230 
231/* Get and/or change the set of blocked signals. */ 
232extern int sigprocmask (int __how, const sigset_t *__restrict __set, 
233 sigset_t *__restrict __oset) __THROW; 
234 
235/* Change the set of blocked signals to SET, 
236 wait until a signal arrives, and restore the set of blocked signals. 
237 
238 This function is a cancellation point and therefore not marked with 
239 __THROW. */ 
240extern int sigsuspend (const sigset_t *__set) __nonnull ((1)); 
241 
242/* Get and/or set the action for signal SIG. */ 
243extern int sigaction (int __sig, const struct sigaction *__restrict __act, 
244 struct sigaction *__restrict __oact) __THROW; 
245 
246/* Put in SET all signals that are blocked and waiting to be delivered. */ 
247extern int sigpending (sigset_t *__set) __THROW __nonnull ((1)); 
248 
249 
250# ifdef __USE_POSIX199506 
251/* Select any of pending signals from SET or wait for any to arrive. 
252 
253 This function is a cancellation point and therefore not marked with 
254 __THROW. */ 
255extern int sigwait (const sigset_t *__restrict __set, int *__restrict __sig) 
256 __nonnull ((1, 2)); 
257# endif /* Use POSIX 1995. */ 
258 
259# ifdef __USE_POSIX199309 
260/* Select any of pending signals from SET and place information in INFO. 
261 
262 This function is a cancellation point and therefore not marked with 
263 __THROW. */ 
264extern int sigwaitinfo (const sigset_t *__restrict __set, 
265 siginfo_t *__restrict __info) __nonnull ((1)); 
266 
267/* Select any of pending signals from SET and place information in INFO. 
268 Wait the time specified by TIMEOUT if no signal is pending. 
269 
270 This function is a cancellation point and therefore not marked with 
271 __THROW. */ 
272# ifndef __USE_TIME_BITS64 
273extern int sigtimedwait (const sigset_t *__restrict __set, 
274 siginfo_t *__restrict __info, 
275 const struct timespec *__restrict __timeout) 
276 __nonnull ((1)); 
277# else 
278# ifdef __REDIRECT 
279extern int __REDIRECT (sigtimedwait, 
280 (const sigset_t *__restrict __set, 
281 siginfo_t *__restrict __info, 
282 const struct timespec *__restrict __timeout), 
283 __sigtimedwait64) 
284 __nonnull ((1)); 
285# else 
286# define sigtimedwait __sigtimedwait64 
287# endif 
288# endif 
289 
290/* Send signal SIG to the process PID. Associate data in VAL with the 
291 signal. */ 
292extern int sigqueue (__pid_t __pid, int __sig, const union sigval __val) 
293 __THROW; 
294# endif /* Use POSIX 199306. */ 
295 
296#endif /* Use POSIX. */ 
297 
298#ifdef __USE_MISC 
299 
300/* Get machine-dependent `struct sigcontext' and signal subcodes. */ 
301# include <bits/sigcontext.h> 
302 
303/* Restore the state saved in SCP. */ 
304extern int sigreturn (struct sigcontext *__scp) __THROW; 
305 
306#endif /* Use misc. */ 
307 
308 
309#if defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K8 
310# define __need_size_t 
311# include <stddef.h> 
312 
313# include <bits/types/stack_t.h> 
314# if defined __USE_XOPEN || defined __USE_XOPEN2K8 
315/* This will define `ucontext_t' and `mcontext_t'. */ 
316# include <sys/ucontext.h> 
317# endif 
318#endif /* Use POSIX.1-2008 or X/Open Unix. */ 
319 
320#if defined __USE_XOPEN_EXTENDED || defined __USE_MISC 
321/* If INTERRUPT is nonzero, make signal SIG interrupt system calls 
322 (causing them to fail with EINTR); if INTERRUPT is zero, make system 
323 calls be restarted after signal SIG. */ 
324extern int siginterrupt (int __sig, int __interrupt) __THROW 
325 __attribute_deprecated_msg__ ("Use sigaction with SA_RESTART instead"); 
326 
327# include <bits/sigstack.h> 
328# include <bits/sigstksz.h> 
329# include <bits/ss_flags.h> 
330 
331/* Alternate signal handler stack interface. 
332 This interface should always be preferred over `sigstack'. */ 
333extern int sigaltstack (const stack_t *__restrict __ss, 
334 stack_t *__restrict __oss) __THROW; 
335#endif /* __USE_XOPEN_EXTENDED || __USE_MISC */ 
336 
337#if ((defined __USE_XOPEN_EXTENDED && !defined __USE_XOPEN2K8) \ 
338 || defined __USE_MISC) 
339# include <bits/types/struct_sigstack.h> 
340#endif 
341 
342#if ((defined __USE_XOPEN_EXTENDED && !defined __USE_XOPEN2K) \ 
343 || defined __USE_MISC) 
344/* Run signals handlers on the stack specified by SS (if not NULL). 
345 If OSS is not NULL, it is filled in with the old signal stack status. 
346 This interface is obsolete and on many platform not implemented. */ 
347extern int sigstack (struct sigstack *__ss, struct sigstack *__oss) 
348 __THROW __attribute_deprecated__; 
349#endif 
350 
351#ifdef __USE_XOPEN_EXTENDED 
352/* Simplified interface for signal management. */ 
353 
354/* Add SIG to the calling process' signal mask. */ 
355extern int sighold (int __sig) __THROW 
356 __attribute_deprecated_msg__ ("Use the sigprocmask function instead"); 
357 
358/* Remove SIG from the calling process' signal mask. */ 
359extern int sigrelse (int __sig) __THROW 
360 __attribute_deprecated_msg__ ("Use the sigprocmask function instead"); 
361 
362/* Set the disposition of SIG to SIG_IGN. */ 
363extern int sigignore (int __sig) __THROW 
364 __attribute_deprecated_msg__ ("Use the signal function instead"); 
365 
366/* Set the disposition of SIG. */ 
367extern __sighandler_t sigset (int __sig, __sighandler_t __disp) __THROW 
368 __attribute_deprecated_msg__ 
369 ("Use the signal and sigprocmask functions instead"); 
370#endif 
371 
372#if defined __USE_POSIX199506 || defined __USE_UNIX98 
373/* Some of the functions for handling signals in threaded programs must 
374 be defined here. */ 
375# include <bits/pthreadtypes.h> 
376# include <bits/sigthread.h> 
377#endif /* use Unix98 */ 
378 
379/* The following functions are used internally in the C library and in 
380 other code which need deep insights. */ 
381 
382/* Return number of available real-time signal with highest priority. */ 
383extern int __libc_current_sigrtmin (void) __THROW; 
384/* Return number of available real-time signal with lowest priority. */ 
385extern int __libc_current_sigrtmax (void) __THROW; 
386 
387#define SIGRTMIN (__libc_current_sigrtmin ()) 
388#define SIGRTMAX (__libc_current_sigrtmax ()) 
389 
390/* System-specific extensions. */ 
391#include <bits/signal_ext.h> 
392 
393__END_DECLS 
394 
395#endif /* not signal.h */ 
396