signal/signal.h

   1 /* Copyright (C) 1991, 1992, 1993, 1994, 1995 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 Library General Public License as
   6 published by the Free Software Foundation; either version 2 of the
   7 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 Library General Public License for more details.
  13
  14 You should have received a copy of the GNU Library General Public
  15 License along with the GNU C Library; see the file COPYING.LIB.  If
  16 not, write to the, 1992 Free Software Foundation, Inc., 675 Mass Ave,
  17 Cambridge, MA 02139, USA.  */
  18
  19 /*
  20  *      ANSI Standard: 4.7 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       1
  27 #include <features.h>
  28 #endif
  29
  30 __BEGIN_DECLS
  31
  32 #define  __need_size_t
  33 #include <stddef.h>
  34
  35 #include <gnu/types.h>
  36 #include <sigset.h>             /* __sigset_t, __sig_atomic_t.  */
  37
  38 #if     !defined(__sig_atomic_t_defined) &&     \
  39   (defined(_SIGNAL_H) || defined(__need_sig_atomic_t))
  40 /* An integral type that can be modified atomically, without the
  41    possibility of a signal arriving in the middle of the operation.  */
  42 typedef __sig_atomic_t sig_atomic_t;
  43 #endif /* `sig_atomic_t' undefined and <signal.h> or need `sig_atomic_t'.  */
  44 #undef  __need_sig_atomic_t
  45
  46 #ifdef  _SIGNAL_H
  47
  48 #include <signum.h>
  49
  50 /* Type of a signal handler.  */
  51 typedef void (*__sighandler_t) __P ((int));
  52
  53 /* Set the handler for the signal SIG to HANDLER,
  54    returning the old handler, or SIG_ERR on error.  */
  55 extern __sighandler_t signal __P ((int __sig, __sighandler_t __handler));
  56
  57 /* Send signal SIG to process number PID.  If PID is zero,
  58    send SIG to all processes in the current process's process group.
  59    If PID is < -1, send SIG to all processes in process group - PID.  */
  60 extern int __kill __P ((__pid_t __pid, int __sig));
  61 #ifdef  __USE_POSIX
  62 extern int kill __P ((__pid_t __pid, int __sig));
  63 #endif /* Use POSIX.  */
  64
  65 #ifdef  __USE_BSD
  66 /* Send SIG to all processes in process group PGRP.
  67    If PGRP is zero, send SIG to all processes in
  68    the current process's process group.  */
  69 extern int killpg __P ((__pid_t __pgrp, int __sig));
  70 #endif /* Use BSD.  */
  71
  72 /* Raise signal SIG, i.e., send SIG to yourself.  */
  73 extern int raise __P ((int __sig));
  74
  75 #ifdef  __USE_SVID
  76 /* SVID names for the same things.  */
  77 extern __sighandler_t ssignal __P ((int __sig, __sighandler_t __handler));
  78 extern int gsignal __P ((int __sig));
  79 #endif /* Use SVID.  */
  80
  81 #ifdef  __USE_MISC
  82 /* Print a message describing the meaning of the given signal number.  */
  83 extern void psignal __P ((int __sig, __const char *__s));
  84 #endif /* Use misc.  */
  85
  86
  87 /* Block signals in MASK, returning the old mask.  */
  88 extern int __sigblock __P ((int __mask));
  89
  90 /* Set the mask of blocked signals to MASK, returning the old mask.  */
  91 extern int __sigsetmask __P ((int __mask));
  92
  93 /* Set the mask of blocked signals to MASK,
  94    wait for a signal to arrive, and then restore the mask.  */
  95 extern int __sigpause __P ((int __mask));
  96
  97 #ifdef  __USE_BSD
  98 #define sigmask(sig)    __sigmask(sig)
  99
 100 extern int sigblock __P ((int __mask));
 101 extern int sigsetmask __P ((int __mask));
 102 extern int sigpause __P ((int __mask));
 103 #endif /* Use BSD.  */
 104
 105
 106 #ifdef  __USE_MISC
 107 #define NSIG    _NSIG
 108 #endif
 109
 110 #ifdef  __USE_GNU
 111 typedef __sighandler_t sighandler_t;
 112 #endif
 113
 114 /* 4.4 BSD uses the name `sig_t' for this.  */
 115 #ifdef  __USE_BSD
 116 typedef __sighandler_t sig_t;
 117 #endif
 118
 119 #endif /* <signal.h> included.  */
 120
 121
 122 #ifdef  __USE_POSIX
 123
 124 #if     !defined(__sigset_t_defined) && \
 125    (defined(_SIGNAL_H) || defined(__need_sigset_t))
 126 typedef __sigset_t sigset_t;
 127 #define __sigset_t_defined      1
 128 #endif /* `sigset_t' not defined and <signal.h> or need `sigset_t'.  */
 129 #undef  __need_sigset_t
 130
 131 #ifdef  _SIGNAL_H
 132
 133 /* Clear all signals from SET.  */
 134 extern int sigemptyset __P ((sigset_t *__set));
 135
 136 /* Set all signals in SET.  */
 137 extern int sigfillset __P ((sigset_t *__set));
 138
 139 /* Add SIGNO to SET.  */
 140 extern int sigaddset __P ((sigset_t *__set, int __signo));
 141
 142 /* Remove SIGNO from SET.  */
 143 extern int sigdelset __P ((sigset_t *__set, int __signo));
 144
 145 /* Return 1 if SIGNO is in SET, 0 if not.  */
 146 extern int sigismember __P ((__const sigset_t *__set, int signo));
 147
 148 #ifdef  __OPTIMIZE__
 149 /* <sigset.h> defines the __ versions as macros that do the work.  */
 150 #define sigemptyset(set)        __sigemptyset(set)
 151 #define sigfillset(set)         __sigfillset(set)
 152 #define sigaddset(set, signo)   __sigaddset(set, signo)
 153 #define sigdelset(set, signo)   __sigdelset(set, signo)
 154 #define sigismember(set, signo) __sigismember(set, signo)
 155 #endif
 156
 157 /* Get the system-specific definitions of `struct sigaction'
 158    and the `SA_*' and `SIG_*'. constants.  */
 159 #include <sigaction.h>
 160
 161 /* Get and/or change the set of blocked signals.  */
 162 extern int __sigprocmask __P ((int __how,
 163                                __const sigset_t *__set, sigset_t *__oset));
 164 extern int sigprocmask __P ((int __how,
 165                              __const sigset_t *__set, sigset_t *__oset));
 166
 167 /* Change the set of blocked signals to SET,
 168    wait until a signal arrives, and restore the set of blocked signals.  */
 169 extern int sigsuspend __P ((__const sigset_t *__set));
 170
 171 /* Get and/or set the action for signal SIG.  */
 172 extern int __sigaction __P ((int __sig, __const struct sigaction *__act,
 173                              struct sigaction *__oact));
 174 extern int sigaction __P ((int __sig, __const struct sigaction *__act,
 175                            struct sigaction *__oact));
 176
 177 /* Put in SET all signals that are blocked and waiting to be delivered.  */
 178 extern int sigpending __P ((sigset_t *__set));
 179
 180 #endif /* <signal.h> included.  */
 181
 182 #endif /* Use POSIX.  */
 183
 184 #if     defined(_SIGNAL_H) && defined(__USE_BSD)
 185
 186 /* Names of the signals.  This variable exists only for compatiblity.
 187    Use `strsignal' instead (see <string.h>).  */
 188 extern __const char *__const _sys_siglist[NSIG];
 189 extern __const char *__const sys_siglist[NSIG];
 190
 191 /* Structure passed to `sigvec'.  */
 192 struct sigvec
 193   {
 194     __sighandler_t sv_handler;  /* Signal handler.  */
 195     int sv_mask;                /* Mask of signals to be blocked.  */
 196
 197     int sv_flags;               /* Flags (see below).  */
 198 #define sv_onstack      sv_flags /* 4.2 BSD compatibility.  */
 199   };
 200
 201 /* Bits in `sv_flags'.  */
 202 #define SV_ONSTACK      (1 << 0)/* Take the signal on the signal stack.  */
 203 #define SV_INTERRUPT    (1 << 1)/* Do not restart system calls.  */
 204 #define SV_RESETHAND    (1 << 2)/* Reset handler to SIG_DFL on receipt.  */
 205
 206
 207 /* If VEC is non-NULL, set the handler for SIG to the `sv_handler' member
 208    of VEC.  The signals in `sv_mask' will be blocked while the handler runs.
 209    If the SV_RESETHAND bit is set in `sv_flags', the handler for SIG will be
 210    reset to SIG_DFL before `sv_handler' is entered.  If OVEC is non-NULL,
 211    it is filled in with the old information for SIG.  */
 212 extern int __sigvec __P ((int __sig, __const struct sigvec *__vec,
 213                           struct sigvec *__ovec));
 214 extern int sigvec __P ((int __sig, __const struct sigvec *__vec,
 215                         struct sigvec *__ovec));
 216
 217
 218 /* If INTERRUPT is nonzero, make signal SIG interrupt system calls
 219    (causing them to fail with EINTR); if INTERRUPT is zero, make system
 220    calls be restarted after signal SIG.  */
 221 extern int siginterrupt __P ((int __sig, int __interrupt));
 222
 223
 224 /* Structure describing a signal stack.  */
 225 struct sigstack
 226   {
 227     __ptr_t ss_sp;              /* Signal stack pointer.  */
 228     int ss_onstack;             /* Nonzero if executing on this stack.  */
 229   };
 230
 231 /* Run signals handlers on the stack specified by SS (if not NULL).
 232    If OSS is not NULL, it is filled in with the old signal stack status.  */
 233 extern int sigstack __P ((__const struct sigstack *__ss,
 234                           struct sigstack *__oss));
 235
 236 /* Alternate interface.  */
 237 struct sigaltstack
 238   {
 239     __ptr_t ss_sp;
 240     size_t ss_size;
 241     int ss_flags;
 242   };
 243
 244 extern int sigaltstack __P ((__const struct sigaltstack *__ss,
 245                              struct sigaltstack *__oss));
 246
 247 /* Get machine-dependent `struct sigcontext' and signal subcodes.  */
 248 #include <sigcontext.h>
 249
 250 /* Restore the state saved in SCP.  */
 251 extern int __sigreturn __P ((struct sigcontext *__scp));
 252 extern int sigreturn __P ((struct sigcontext *__scp));
 253
 254 #endif /* signal.h included and use BSD.  */
 255
 256 __END_DECLS
 257
 258 #endif /* signal.h  */