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 #ifndef _BITS_SIGACTION_H 19 #define _BITS_SIGACTION_H 1 20 21 #ifndef _SIGNAL_H 22 # error "Never include <bits/sigaction.h> directly; use <signal.h> instead." 23 #endif 24 25 /* These definitions match those used by the 4.4 BSD kernel. 26 If the operating system has a `sigaction' system call that correctly 27 implements the POSIX.1 behavior, there should be a system-dependent 28 version of this file that defines `struct sigaction' and the `SA_*' 29 constants appropriately. */ 30 31 /* Structure describing the action to be taken when a signal arrives. */ 32 struct sigaction 33 { 34 /* Signal handler. */ 35 #if defined __USE_POSIX199309 || defined __USE_XOPEN_EXTENDED 36 union 37 { 38 /* Used if SA_SIGINFO is not set. */ 39 __sighandler_t sa_handler; 40 /* Used if SA_SIGINFO is set. */ 41 void (*sa_sigaction) (int, siginfo_t *, void *); 42 } 43 __sigaction_handler; 44 # define sa_handler __sigaction_handler.sa_handler 45 # define sa_sigaction __sigaction_handler.sa_sigaction 46 #else 47 __sighandler_t sa_handler; 48 #endif 49 50 /* Additional set of signals to be blocked. */ 51 __sigset_t sa_mask; 52 53 /* Special flags. */ 54 int sa_flags; 55 }; 56 57 /* Bits in `sa_flags'. */ 58 #if defined __USE_XOPEN_EXTENDED || defined __USE_MISC 59 # define SA_ONSTACK 0x0001 /* Take signal on signal stack. */ 60 #endif 61 #if defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K8 62 # define SA_RESTART 0x0002 /* Restart syscall on signal return. */ 63 # define SA_NODEFER 0x0010 /* Don't automatically block the signal when 64 its handler is being executed. */ 65 # define SA_RESETHAND 0x0004 /* Reset to SIG_DFL on entry to handler. */ 66 #endif 67 #define SA_NOCLDSTOP 0x0008 /* Don't send SIGCHLD when children stop. */ 68 #define SA_SIGINFO 0x0040 /* Signal handler with SA_SIGINFO args */ 69 70 #ifdef __USE_MISC 71 # define SA_INTERRUPT 0 /* Historical no-op ("not SA_RESTART"). */ 72 73 /* Some aliases for the SA_ constants. */ 74 # define SA_NOMASK SA_NODEFER 75 # define SA_ONESHOT SA_RESETHAND 76 # define SA_STACK SA_ONSTACK 77 #endif 78 79 80 /* Values for the HOW argument to `sigprocmask'. */ 81 #define SIG_BLOCK 1 /* Block signals. */ 82 #define SIG_UNBLOCK 2 /* Unblock signals. */ 83 #define SIG_SETMASK 3 /* Set the set of blocked signals. */ 84 85 #endif 86