1  /* The proper definitions for Linux/Alpha sigaction.
       2     Copyright (C) 1996-2023 Free Software Foundation, Inc.
       3     This file is part of the GNU C Library.
       4  
       5     The GNU C Library is free software; you can redistribute it and/or
       6     modify it under the terms of the GNU Lesser General Public
       7     License as published by the Free Software Foundation; either
       8     version 2.1 of the License, or (at your option) any later version.
       9  
      10     The GNU C Library is distributed in the hope that it will be useful,
      11     but WITHOUT ANY WARRANTY; without even the implied warranty of
      12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
      13     Lesser General Public License for more details.
      14  
      15     You should have received a copy of the GNU Lesser General Public
      16     License along with the GNU C Library.  If not, see
      17     <https://www.gnu.org/licenses/>.  */
      18  
      19  #ifndef _BITS_SIGACTION_H
      20  #define _BITS_SIGACTION_H 1
      21  
      22  #ifndef _SIGNAL_H
      23  # error "Never include <bits/sigaction.h> directly; use <signal.h> instead."
      24  #endif
      25  
      26  /* Structure describing the action to be taken when a signal arrives.  */
      27  struct sigaction
      28    {
      29      /* Signal handler.  */
      30  #if defined __USE_POSIX199309 || defined __USE_XOPEN_EXTENDED
      31      union
      32        {
      33  	/* Used if SA_SIGINFO is not set.  */
      34  	__sighandler_t sa_handler;
      35  	/* Used if SA_SIGINFO is set.  */
      36  	void (*sa_sigaction) (int, siginfo_t *, void *);
      37        }
      38      __sigaction_handler;
      39  # define sa_handler	__sigaction_handler.sa_handler
      40  # define sa_sigaction	__sigaction_handler.sa_sigaction
      41  #else
      42      __sighandler_t sa_handler;
      43  #endif
      44  
      45      /* Additional set of signals to be blocked.  */
      46      __sigset_t sa_mask;
      47  
      48      /* Special flags.  */
      49      int sa_flags;
      50    };
      51  
      52  /* Bits in `sa_flags'.  */
      53  #define	SA_NOCLDSTOP  0x00000004 /* Don't send SIGCHLD when children stop.  */
      54  #define SA_NOCLDWAIT  0x00000020 /* Don't create zombie on child death.  */
      55  #define SA_SIGINFO    0x00000040 /* Invoke signal-catching function with
      56  				    three arguments instead of one.  */
      57  #if defined __USE_XOPEN_EXTENDED || defined __USE_MISC
      58  # define SA_ONSTACK   0x00000001 /* Use signal stack by using `sa_restorer'. */
      59  #endif
      60  #if defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K8
      61  # define SA_RESTART   0x00000002 /* Restart syscall on signal return.  */
      62  # define SA_NODEFER   0x00000008 /* Don't automatically block the signal
      63  				    when its handler is being executed.  */
      64  # define SA_RESETHAND 0x00000010 /* Reset to SIG_DFL on entry to handler.  */
      65  #endif
      66  #ifdef __USE_MISC
      67  # define SA_INTERRUPT 0x20000000 /* Historical no-op.  */
      68  
      69  /* Some aliases for the SA_ constants.  */
      70  # define SA_NOMASK    SA_NODEFER
      71  # define SA_ONESHOT   SA_RESETHAND
      72  # define SA_STACK     SA_ONSTACK
      73  #endif
      74  
      75  /* Values for the HOW argument to `sigprocmask'.  */
      76  #define	SIG_BLOCK     1		 /* Block signals.  */
      77  #define	SIG_UNBLOCK   2		 /* Unblock signals.  */
      78  #define	SIG_SETMASK   3		 /* Set the set of blocked signals.  */
      79  
      80  #endif