1 /* Copyright (C) 1991-2004, 2007, 2009, 2010 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, write to the Free
16 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
17 02111-1307 USA. */
18
19 /*
20 * ISO C99 Standard: 7.14 Signal handling <signal.h>
21 */
22
23 #ifndef _SIGNAL_H
24
25 #if !defined __need_sig_atomic_t && !defined __need_sigset_t
26 # define _SIGNAL_H
27 #endif
28
29 #include <features.h>
30
31 __BEGIN_DECLS
32
33 #include <bits/sigset.h> /* __sigset_t, __sig_atomic_t. */
34
35 /* An integral type that can be modified atomically, without the
36 possibility of a signal arriving in the middle of the operation. */
37 #if defined __need_sig_atomic_t || defined _SIGNAL_H
38 # ifndef __sig_atomic_t_defined
39 # define __sig_atomic_t_defined
40 __BEGIN_NAMESPACE_STD
41 typedef __sig_atomic_t sig_atomic_t;
42 __END_NAMESPACE_STD
43 # endif
44 # undef __need_sig_atomic_t
45 #endif
46
47 #if defined __need_sigset_t || (defined _SIGNAL_H && defined __USE_POSIX)
48 # ifndef __sigset_t_defined
49 # define __sigset_t_defined
50 typedef __sigset_t sigset_t;
51 # endif
52 # undef __need_sigset_t
53 #endif
54
55 #ifdef _SIGNAL_H
56
57 #include <bits/types.h>
58 #include <bits/signum.h>
59
60 #if defined __USE_XOPEN || defined __USE_XOPEN2K
61 # ifndef __pid_t_defined
62 typedef __pid_t pid_t;
63 # define __pid_t_defined
64 #endif
65 #ifdef __USE_XOPEN
66 # endif
67 # ifndef __uid_t_defined
68 typedef __uid_t uid_t;
69 # define __uid_t_defined
70 # endif
71 #endif /* Unix98 */
72
73 #ifdef __USE_POSIX199309
74 /* We need `struct timespec' later on. */
75 # define __need_timespec
76 # include <time.h>
77
78 /* Get the `siginfo_t' type plus the needed symbols. */
79 # include <bits/siginfo.h>
80 #endif
81
82
83 /* Type of a signal handler. */
84 typedef void (*__sighandler_t) (int);
85
86 /* The X/Open definition of `signal' specifies the SVID semantic. Use
87 the additional function `sysv_signal' when X/Open compatibility is
88 requested. */
89 extern __sighandler_t __sysv_signal (int __sig, __sighandler_t __handler)
90 __THROW;
91 #ifdef __USE_GNU
92 extern __sighandler_t sysv_signal (int __sig, __sighandler_t __handler)
93 __THROW;
94 #endif
95
96 /* Set the handler for the signal SIG to HANDLER, returning the old
97 handler, or SIG_ERR on error.
98 By default `signal' has the BSD semantic. */
99 __BEGIN_NAMESPACE_STD
100 #ifdef __USE_BSD
101 extern __sighandler_t signal (int __sig, __sighandler_t __handler)
102 __THROW;
103 #else
104 /* Make sure the used `signal' implementation is the SVID version. */
105 # ifdef __REDIRECT_NTH
106 extern __sighandler_t __REDIRECT_NTH (signal,
107 (int __sig, __sighandler_t __handler),
108 __sysv_signal);
109 # else
110 # define signal __sysv_signal
111 # endif
112 #endif
113 __END_NAMESPACE_STD
114
115 #ifdef __USE_XOPEN
116 /* The X/Open definition of `signal' conflicts with the BSD version.
117 So they defined another function `bsd_signal'. */
118 extern __sighandler_t bsd_signal (int __sig, __sighandler_t __handler)
119 __THROW;
120 #endif
121
122 /* Send signal SIG to process number PID. If PID is zero,
123 send SIG to all processes in the current process's process group.
124 If PID is < -1, send SIG to all processes in process group - PID. */
125 #ifdef __USE_POSIX
126 extern int kill (__pid_t __pid, int __sig) __THROW;
127 #endif /* Use POSIX. */
128
129 #if defined __USE_BSD || defined __USE_XOPEN_EXTENDED
130 /* Send SIG to all processes in process group PGRP.
131 If PGRP is zero, send SIG to all processes in
132 the current process's process group. */
133 extern int killpg (__pid_t __pgrp, int __sig) __THROW;
134 #endif /* Use BSD || X/Open Unix. */
135
136 __BEGIN_NAMESPACE_STD
137 /* Raise signal SIG, i.e., send SIG to yourself. */
138 extern int raise (int __sig) __THROW;
139 __END_NAMESPACE_STD
140
141 #ifdef __USE_SVID
142 /* SVID names for the same things. */
143 extern __sighandler_t ssignal (int __sig, __sighandler_t __handler)
144 __THROW;
145 extern int gsignal (int __sig) __THROW;
146 #endif /* Use SVID. */
147
148 #if defined __USE_MISC || defined __USE_XOPEN2K
149 /* Print a message describing the meaning of the given signal number. */
150 extern void psignal (int __sig, __const char *__s);
151 #endif /* Use misc or POSIX 2008. */
152
153 #ifdef __USE_XOPEN2K
154 /* Print a message describing the meaning of the given signal information. */
155 extern void psiginfo (__const siginfo_t *__pinfo, __const char *__s);
156 #endif /* POSIX 2008. */
157
158
159
160 /* The `sigpause' function has two different interfaces. The original
161 BSD definition defines the argument as a mask of the signal, while
162 the more modern interface in X/Open defines it as the signal
163 number. We go with the BSD version unless the user explicitly
164 selects the X/Open version.
165
166 This function is a cancellation point and therefore not marked with
167 __THROW. */
168 extern int __sigpause (int __sig_or_mask, int __is_sig);
169
170 #ifdef __FAVOR_BSD
171 /* Set the mask of blocked signals to MASK,
172 wait for a signal to arrive, and then restore the mask. */
173 extern int sigpause (int __mask) __THROW __attribute_deprecated__;
174 #else
175 # ifdef __USE_XOPEN
176 # ifdef __GNUC__
177 extern int sigpause (int __sig) __asm__ ("__xpg_sigpause");
178 # else
179 /* Remove a signal from the signal mask and suspend the process. */
180 # define sigpause(sig) __sigpause ((sig), 1)
181 # endif
182 # endif
183 #endif
184
185
186 #ifdef __USE_BSD
187 /* None of the following functions should be used anymore. They are here
188 only for compatibility. A single word (`int') is not guaranteed to be
189 enough to hold a complete signal mask and therefore these functions
190 simply do not work in many situations. Use `sigprocmask' instead. */
191
192 /* Compute mask for signal SIG. */
193 # define sigmask(sig) __sigmask(sig)
194
195 /* Block signals in MASK, returning the old mask. */
196 extern int sigblock (int __mask) __THROW __attribute_deprecated__;
197
198 /* Set the mask of blocked signals to MASK, returning the old mask. */
199 extern int sigsetmask (int __mask) __THROW __attribute_deprecated__;
200
201 /* Return currently selected signal mask. */
202 extern int siggetmask (void) __THROW __attribute_deprecated__;
203 #endif /* Use BSD. */
204
205
206 #ifdef __USE_MISC
207 # define NSIG _NSIG
208 #endif
209
210 #ifdef __USE_GNU
211 typedef __sighandler_t sighandler_t;
212 #endif
213
214 /* 4.4 BSD uses the name `sig_t' for this. */
215 #ifdef __USE_BSD
216 typedef __sighandler_t sig_t;
217 #endif
218
219 #ifdef __USE_POSIX
220
221 /* Clear all signals from SET. */
222 extern int sigemptyset (sigset_t *__set) __THROW __nonnull ((1));
223
224 /* Set all signals in SET. */
225 extern int sigfillset (sigset_t *__set) __THROW __nonnull ((1));
226
227 /* Add SIGNO to SET. */
228 extern int sigaddset (sigset_t *__set, int __signo) __THROW __nonnull ((1));
229
230 /* Remove SIGNO from SET. */
231 extern int sigdelset (sigset_t *__set, int __signo) __THROW __nonnull ((1));
232
233 /* Return 1 if SIGNO is in SET, 0 if not. */
234 extern int sigismember (__const sigset_t *__set, int __signo)
235 __THROW __nonnull ((1));
236
237 # ifdef __USE_GNU
238 /* Return non-empty value is SET is not empty. */
239 extern int sigisemptyset (__const sigset_t *__set) __THROW __nonnull ((1));
240
241 /* Build new signal set by combining the two inputs set using logical AND. */
242 extern int sigandset (sigset_t *__set, __const sigset_t *__left,
243 __const sigset_t *__right) __THROW __nonnull ((1, 2, 3));
244
245 /* Build new signal set by combining the two inputs set using logical OR. */
246 extern int sigorset (sigset_t *__set, __const sigset_t *__left,
247 __const sigset_t *__right) __THROW __nonnull ((1, 2, 3));
248 # endif /* GNU */
249
250 /* Get the system-specific definitions of `struct sigaction'
251 and the `SA_*' and `SIG_*'. constants. */
252 # include <bits/sigaction.h>
253
254 /* Get and/or change the set of blocked signals. */
255 extern int sigprocmask (int __how, __const sigset_t *__restrict __set,
256 sigset_t *__restrict __oset) __THROW;
257
258 /* Change the set of blocked signals to SET,
259 wait until a signal arrives, and restore the set of blocked signals.
260
261 This function is a cancellation point and therefore not marked with
262 __THROW. */
263 extern int sigsuspend (__const sigset_t *__set) __nonnull ((1));
264
265 /* Get and/or set the action for signal SIG. */
266 extern int sigaction (int __sig, __const struct sigaction *__restrict __act,
267 struct sigaction *__restrict __oact) __THROW;
268
269 /* Put in SET all signals that are blocked and waiting to be delivered. */
270 extern int sigpending (sigset_t *__set) __THROW __nonnull ((1));
271
272
273 /* Select any of pending signals from SET or wait for any to arrive.
274
275 This function is a cancellation point and therefore not marked with
276 __THROW. */
277 extern int sigwait (__const sigset_t *__restrict __set, int *__restrict __sig)
278 __nonnull ((1, 2));
279
280 # ifdef __USE_POSIX199309
281 /* Select any of pending signals from SET and place information in INFO.
282
283 This function is a cancellation point and therefore not marked with
284 __THROW. */
285 extern int sigwaitinfo (__const sigset_t *__restrict __set,
286 siginfo_t *__restrict __info) __nonnull ((1));
287
288 /* Select any of pending signals from SET and place information in INFO.
289 Wait the time specified by TIMEOUT if no signal is pending.
290
291 This function is a cancellation point and therefore not marked with
292 __THROW. */
293 extern int sigtimedwait (__const sigset_t *__restrict __set,
294 siginfo_t *__restrict __info,
295 __const struct timespec *__restrict __timeout)
296 __nonnull ((1));
297
298 /* Send signal SIG to the process PID. Associate data in VAL with the
299 signal. */
300 extern int sigqueue (__pid_t __pid, int __sig, __const union sigval __val)
301 __THROW;
302 # endif /* Use POSIX 199306. */
303
304 #endif /* Use POSIX. */
305
306 #ifdef __USE_BSD
307
308 /* Names of the signals. This variable exists only for compatibility.
309 Use `strsignal' instead (see <string.h>). */
310 extern __const char *__const _sys_siglist[_NSIG];
311 extern __const char *__const sys_siglist[_NSIG];
312
313 /* Structure passed to `sigvec'. */
314 struct sigvec
315 {
316 __sighandler_t sv_handler; /* Signal handler. */
317 int sv_mask; /* Mask of signals to be blocked. */
318
319 int sv_flags; /* Flags (see below). */
320 # define sv_onstack sv_flags /* 4.2 BSD compatibility. */
321 };
322
323 /* Bits in `sv_flags'. */
324 # define SV_ONSTACK (1 << 0)/* Take the signal on the signal stack. */
325 # define SV_INTERRUPT (1 << 1)/* Do not restart system calls. */
326 # define SV_RESETHAND (1 << 2)/* Reset handler to SIG_DFL on receipt. */
327
328
329 /* If VEC is non-NULL, set the handler for SIG to the `sv_handler' member
330 of VEC. The signals in `sv_mask' will be blocked while the handler runs.
331 If the SV_RESETHAND bit is set in `sv_flags', the handler for SIG will be
332 reset to SIG_DFL before `sv_handler' is entered. If OVEC is non-NULL,
333 it is filled in with the old information for SIG. */
334 extern int sigvec (int __sig, __const struct sigvec *__vec,
335 struct sigvec *__ovec) __THROW;
336
337
338 /* Get machine-dependent `struct sigcontext' and signal subcodes. */
339 # include <bits/sigcontext.h>
340
341 /* Restore the state saved in SCP. */
342 extern int sigreturn (struct sigcontext *__scp) __THROW;
343
344 #endif /* use BSD. */
345
346
347 #if defined __USE_BSD || defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K8
348 # define __need_size_t
349 # include <stddef.h>
350
351 /* If INTERRUPT is nonzero, make signal SIG interrupt system calls
352 (causing them to fail with EINTR); if INTERRUPT is zero, make system
353 calls be restarted after signal SIG. */
354 extern int siginterrupt (int __sig, int __interrupt) __THROW;
355
356 # include <bits/sigstack.h>
357 # if defined __USE_XOPEN || defined __USE_XOPEN2K8
358 /* This will define `ucontext_t' and `mcontext_t'. */
359 # include <sys/ucontext.h>
360 # endif
361
362 /* Run signals handlers on the stack specified by SS (if not NULL).
363 If OSS is not NULL, it is filled in with the old signal stack status.
364 This interface is obsolete and on many platform not implemented. */
365 extern int sigstack (struct sigstack *__ss, struct sigstack *__oss)
366 __THROW __attribute_deprecated__;
367
368 /* Alternate signal handler stack interface.
369 This interface should always be preferred over `sigstack'. */
370 extern int sigaltstack (__const struct sigaltstack *__restrict __ss,
371 struct sigaltstack *__restrict __oss) __THROW;
372
373 #endif /* use BSD or X/Open Unix. */
374
375 #ifdef __USE_XOPEN_EXTENDED
376 /* Simplified interface for signal management. */
377
378 /* Add SIG to the calling process' signal mask. */
379 extern int sighold (int __sig) __THROW;
380
381 /* Remove SIG from the calling process' signal mask. */
382 extern int sigrelse (int __sig) __THROW;
383
384 /* Set the disposition of SIG to SIG_IGN. */
385 extern int sigignore (int __sig) __THROW;
386
387 /* Set the disposition of SIG. */
388 extern __sighandler_t sigset (int __sig, __sighandler_t __disp) __THROW;
389 #endif
390
391 #if defined __USE_POSIX199506 || defined __USE_UNIX98
392 /* Some of the functions for handling signals in threaded programs must
393 be defined here. */
394 # include <bits/pthreadtypes.h>
395 # include <bits/sigthread.h>
396 #endif /* use Unix98 */
397
398 /* The following functions are used internally in the C library and in
399 other code which need deep insights. */
400
401 /* Return number of available real-time signal with highest priority. */
402 extern int __libc_current_sigrtmin (void) __THROW;
403 /* Return number of available real-time signal with lowest priority. */
404 extern int __libc_current_sigrtmax (void) __THROW;
405
406 #endif /* signal.h */
407
408 __END_DECLS
409
410 #endif /* not signal.h */
411