1 /* Copyright (C) 1991-2015 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
40 typedef __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
49 typedef __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
61 typedef __pid_t pid_t;
62 # define __pid_t_defined
63 #endif
64 #ifdef __USE_XOPEN
65 # endif
66 # ifndef __uid_t_defined
67 typedef __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. */
85 typedef 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. */
90 extern __sighandler_t __sysv_signal (int __sig, __sighandler_t __handler)
91 __THROW;
92 #ifdef __USE_GNU
93 extern __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_MISC
102 extern __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
107 extern __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'. */
119 extern __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
127 extern int kill (__pid_t __pid, int __sig) __THROW;
128 #endif /* Use POSIX. */
129
130 #if defined __USE_MISC || 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. */
134 extern int killpg (__pid_t __pgrp, int __sig) __THROW;
135 #endif /* Use misc || X/Open Unix. */
136
137 __BEGIN_NAMESPACE_STD
138 /* Raise signal SIG, i.e., send SIG to yourself. */
139 extern int raise (int __sig) __THROW;
140 __END_NAMESPACE_STD
141
142 #ifdef __USE_MISC
143 /* SVID names for the same things. */
144 extern __sighandler_t ssignal (int __sig, __sighandler_t __handler)
145 __THROW;
146 extern int gsignal (int __sig) __THROW;
147 #endif /* Use misc. */
148
149 #ifdef __USE_XOPEN2K8
150 /* Print a message describing the meaning of the given signal number. */
151 extern void psignal (int __sig, const char *__s);
152
153 /* Print a message describing the meaning of the given signal information. */
154 extern void psiginfo (const siginfo_t *__pinfo, const char *__s);
155 #endif /* POSIX 2008. */
156
157
158
159 /* The `sigpause' function in X/Open defines the argument as the
160 signal number. This requires redirecting to another function
161 because the default version in glibc uses an old BSD interface.
162
163 This function is a cancellation point and therefore not marked with
164 __THROW. */
165
166 #ifdef __USE_XOPEN
167 # ifdef __GNUC__
168 extern int sigpause (int __sig) __asm__ ("__xpg_sigpause");
169 # else
170 extern int __sigpause (int __sig_or_mask, int __is_sig);
171 /* Remove a signal from the signal mask and suspend the process. */
172 # define sigpause(sig) __sigpause ((sig), 1)
173 # endif
174 #endif
175
176
177 #ifdef __USE_MISC
178 /* None of the following functions should be used anymore. They are here
179 only for compatibility. A single word (`int') is not guaranteed to be
180 enough to hold a complete signal mask and therefore these functions
181 simply do not work in many situations. Use `sigprocmask' instead. */
182
183 /* Compute mask for signal SIG. */
184 # define sigmask(sig) __sigmask(sig)
185
186 /* Block signals in MASK, returning the old mask. */
187 extern int sigblock (int __mask) __THROW __attribute_deprecated__;
188
189 /* Set the mask of blocked signals to MASK, returning the old mask. */
190 extern int sigsetmask (int __mask) __THROW __attribute_deprecated__;
191
192 /* Return currently selected signal mask. */
193 extern int siggetmask (void) __THROW __attribute_deprecated__;
194 #endif /* Use misc. */
195
196
197 #ifdef __USE_MISC
198 # define NSIG _NSIG
199 #endif
200
201 #ifdef __USE_GNU
202 typedef __sighandler_t sighandler_t;
203 #endif
204
205 /* 4.4 BSD uses the name `sig_t' for this. */
206 #ifdef __USE_MISC
207 typedef __sighandler_t sig_t;
208 #endif
209
210 #ifdef __USE_POSIX
211
212 /* Clear all signals from SET. */
213 extern int sigemptyset (sigset_t *__set) __THROW __nonnull ((1));
214
215 /* Set all signals in SET. */
216 extern int sigfillset (sigset_t *__set) __THROW __nonnull ((1));
217
218 /* Add SIGNO to SET. */
219 extern int sigaddset (sigset_t *__set, int __signo) __THROW __nonnull ((1));
220
221 /* Remove SIGNO from SET. */
222 extern int sigdelset (sigset_t *__set, int __signo) __THROW __nonnull ((1));
223
224 /* Return 1 if SIGNO is in SET, 0 if not. */
225 extern int sigismember (const sigset_t *__set, int __signo)
226 __THROW __nonnull ((1));
227
228 # ifdef __USE_GNU
229 /* Return non-empty value is SET is not empty. */
230 extern int sigisemptyset (const sigset_t *__set) __THROW __nonnull ((1));
231
232 /* Build new signal set by combining the two inputs set using logical AND. */
233 extern int sigandset (sigset_t *__set, const sigset_t *__left,
234 const sigset_t *__right) __THROW __nonnull ((1, 2, 3));
235
236 /* Build new signal set by combining the two inputs set using logical OR. */
237 extern int sigorset (sigset_t *__set, const sigset_t *__left,
238 const sigset_t *__right) __THROW __nonnull ((1, 2, 3));
239 # endif /* GNU */
240
241 /* Get the system-specific definitions of `struct sigaction'
242 and the `SA_*' and `SIG_*'. constants. */
243 # include <bits/sigaction.h>
244
245 /* Get and/or change the set of blocked signals. */
246 extern int sigprocmask (int __how, const sigset_t *__restrict __set,
247 sigset_t *__restrict __oset) __THROW;
248
249 /* Change the set of blocked signals to SET,
250 wait until a signal arrives, and restore the set of blocked signals.
251
252 This function is a cancellation point and therefore not marked with
253 __THROW. */
254 extern int sigsuspend (const sigset_t *__set) __nonnull ((1));
255
256 /* Get and/or set the action for signal SIG. */
257 extern int sigaction (int __sig, const struct sigaction *__restrict __act,
258 struct sigaction *__restrict __oact) __THROW;
259
260 /* Put in SET all signals that are blocked and waiting to be delivered. */
261 extern int sigpending (sigset_t *__set) __THROW __nonnull ((1));
262
263
264 /* Select any of pending signals from SET or wait for any to arrive.
265
266 This function is a cancellation point and therefore not marked with
267 __THROW. */
268 extern int sigwait (const sigset_t *__restrict __set, int *__restrict __sig)
269 __nonnull ((1, 2));
270
271 # ifdef __USE_POSIX199309
272 /* Select any of pending signals from SET and place information in INFO.
273
274 This function is a cancellation point and therefore not marked with
275 __THROW. */
276 extern int sigwaitinfo (const sigset_t *__restrict __set,
277 siginfo_t *__restrict __info) __nonnull ((1));
278
279 /* Select any of pending signals from SET and place information in INFO.
280 Wait the time specified by TIMEOUT if no signal is pending.
281
282 This function is a cancellation point and therefore not marked with
283 __THROW. */
284 extern int sigtimedwait (const sigset_t *__restrict __set,
285 siginfo_t *__restrict __info,
286 const struct timespec *__restrict __timeout)
287 __nonnull ((1));
288
289 /* Send signal SIG to the process PID. Associate data in VAL with the
290 signal. */
291 extern int sigqueue (__pid_t __pid, int __sig, const union sigval __val)
292 __THROW;
293 # endif /* Use POSIX 199306. */
294
295 #endif /* Use POSIX. */
296
297 #ifdef __USE_MISC
298
299 /* Names of the signals. This variable exists only for compatibility.
300 Use `strsignal' instead (see <string.h>). */
301 extern const char *const _sys_siglist[_NSIG];
302 extern const char *const sys_siglist[_NSIG];
303
304
305 /* Get machine-dependent `struct sigcontext' and signal subcodes. */
306 # include <bits/sigcontext.h>
307
308 /* Restore the state saved in SCP. */
309 extern int sigreturn (struct sigcontext *__scp) __THROW;
310
311 #endif /* Use misc. */
312
313
314 #if defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K8
315 # define __need_size_t
316 # include <stddef.h>
317
318 /* If INTERRUPT is nonzero, make signal SIG interrupt system calls
319 (causing them to fail with EINTR); if INTERRUPT is zero, make system
320 calls be restarted after signal SIG. */
321 extern int siginterrupt (int __sig, int __interrupt) __THROW;
322
323 # include <bits/sigstack.h>
324 # if defined __USE_XOPEN || defined __USE_XOPEN2K8
325 /* This will define `ucontext_t' and `mcontext_t'. */
326 # include <sys/ucontext.h>
327 # endif
328
329 /* Run signals handlers on the stack specified by SS (if not NULL).
330 If OSS is not NULL, it is filled in with the old signal stack status.
331 This interface is obsolete and on many platform not implemented. */
332 extern int sigstack (struct sigstack *__ss, struct sigstack *__oss)
333 __THROW __attribute_deprecated__;
334
335 /* Alternate signal handler stack interface.
336 This interface should always be preferred over `sigstack'. */
337 extern int sigaltstack (const struct sigaltstack *__restrict __ss,
338 struct sigaltstack *__restrict __oss) __THROW;
339
340 #endif /* Use POSIX.1-2008 or X/Open Unix. */
341
342 #ifdef __USE_XOPEN_EXTENDED
343 /* Simplified interface for signal management. */
344
345 /* Add SIG to the calling process' signal mask. */
346 extern int sighold (int __sig) __THROW;
347
348 /* Remove SIG from the calling process' signal mask. */
349 extern int sigrelse (int __sig) __THROW;
350
351 /* Set the disposition of SIG to SIG_IGN. */
352 extern int sigignore (int __sig) __THROW;
353
354 /* Set the disposition of SIG. */
355 extern __sighandler_t sigset (int __sig, __sighandler_t __disp) __THROW;
356 #endif
357
358 #if defined __USE_POSIX199506 || defined __USE_UNIX98
359 /* Some of the functions for handling signals in threaded programs must
360 be defined here. */
361 # include <bits/pthreadtypes.h>
362 # include <bits/sigthread.h>
363 #endif /* use Unix98 */
364
365 /* The following functions are used internally in the C library and in
366 other code which need deep insights. */
367
368 /* Return number of available real-time signal with highest priority. */
369 extern int __libc_current_sigrtmin (void) __THROW;
370 /* Return number of available real-time signal with lowest priority. */
371 extern int __libc_current_sigrtmax (void) __THROW;
372
373 #endif /* signal.h */
374
375 __END_DECLS
376
377 #endif /* not signal.h */
378