sig.h

/* sig.h -- header file for signal handler definitions. */

/* Copyright (C) 1994-2021 Free Software Foundation, Inc.

   This file is part of GNU Bash, the Bourne Again SHell.

   Bash is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation, either version 3 of the License, or
   (at your option) any later version.

   Bash is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with Bash.  If not, see <http://www.gnu.org/licenses/>.
*/

/* Make sure that this is included *after* config.h! */

#if !defined (_SIG_H_)
#  define _SIG_H_

#include "stdc.h"

#include <signal.h>		/* for sig_atomic_t */

#if !defined (SIGABRT) && defined (SIGIOT)
#  define SIGABRT SIGIOT
#endif

#define sighandler void
typedef void SigHandler PARAMS((int));

#define SIGRETURN(n)	return

/* Here is a definition for set_signal_handler () which simply expands to
   a call to signal () for non-Posix systems.  The code for set_signal_handler
   in the Posix case resides in general.c. */
#if !defined (HAVE_POSIX_SIGNALS)
#  define set_signal_handler(sig, handler) (SigHandler *)signal (sig, handler)
#else
extern SigHandler *set_signal_handler PARAMS((int, SigHandler *));	/* in sig.c */
#endif /* _POSIX_VERSION */

#if !defined (SIGCHLD) && defined (SIGCLD)
#  define SIGCHLD SIGCLD
#endif

#if !defined (HAVE_POSIX_SIGNALS) && !defined (sigmask)
#  define sigmask(x) (1 << ((x)-1))
#endif /* !HAVE_POSIX_SIGNALS && !sigmask */

#if !defined (HAVE_POSIX_SIGNALS)
#  if !defined (SIG_BLOCK)
#    define SIG_BLOCK 2
#    define SIG_SETMASK 3
#  endif /* SIG_BLOCK */

/* sigset_t defined in config.h */

/* Make sure there is nothing inside the signal set. */
#  define sigemptyset(set) (*(set) = 0)

/* Initialize the signal set to hold all signals. */
#  define sigfillset(set) (*set) = sigmask (NSIG) - 1

/* Add SIG to the contents of SET. */
#  define sigaddset(set, sig) *(set) |= sigmask (sig)

/* Delete SIG from signal set SET. */
#  define sigdelset(set, sig) *(set) &= ~sigmask (sig)

/* Is SIG a member of the signal set SET? */
#  define sigismember(set, sig) ((*(set) & sigmask (sig)) != 0)

/* Suspend the process until the reception of one of the signals
   not present in SET. */
#  define sigsuspend(set) sigpause (*(set))
#endif /* !HAVE_POSIX_SIGNALS */

/* These definitions are used both in POSIX and non-POSIX implementations. */

#define BLOCK_SIGNAL(sig, nvar, ovar) \
do { \
  sigemptyset (&nvar); \
  sigaddset (&nvar, sig); \
  sigemptyset (&ovar); \
  sigprocmask (SIG_BLOCK, &nvar, &ovar); \
} while (0)

#define UNBLOCK_SIGNAL(ovar) sigprocmask (SIG_SETMASK, &ovar, (sigset_t *) NULL)

#if defined (HAVE_POSIX_SIGNALS)
#  define BLOCK_CHILD(nvar, ovar) BLOCK_SIGNAL (SIGCHLD, nvar, ovar)
#  define UNBLOCK_CHILD(ovar) UNBLOCK_SIGNAL(ovar)
#else /* !HAVE_POSIX_SIGNALS */
#  define BLOCK_CHILD(nvar, ovar) ovar = sigblock (sigmask (SIGCHLD))
#  define UNBLOCK_CHILD(ovar) sigsetmask (ovar)
#endif /* !HAVE_POSIX_SIGNALS */

/* Extern variables */
extern volatile sig_atomic_t sigwinch_received;
extern volatile sig_atomic_t sigterm_received;

extern int interrupt_immediately;	/* no longer used */
extern int terminate_immediately;

/* Functions from sig.c. */
extern sighandler termsig_sighandler PARAMS((int));
extern void termsig_handler PARAMS((int));
extern sighandler sigint_sighandler PARAMS((int));
extern void initialize_signals PARAMS((int));
extern void initialize_terminating_signals PARAMS((void));
extern void reset_terminating_signals PARAMS((void));
extern void top_level_cleanup PARAMS((void));
extern void throw_to_top_level PARAMS((void));
extern void jump_to_top_level PARAMS((int)) __attribute__((__noreturn__));
extern void restore_sigmask PARAMS((void));

extern sighandler sigwinch_sighandler PARAMS((int));
extern void set_sigwinch_handler PARAMS((void));
extern void unset_sigwinch_handler PARAMS((void));

extern sighandler sigterm_sighandler PARAMS((int));

/* Functions defined in trap.c. */
extern SigHandler *set_sigint_handler PARAMS((void));
extern SigHandler *trap_to_sighandler PARAMS((int));
extern sighandler trap_handler PARAMS((int));

extern int block_trapped_signals PARAMS((sigset_t *, sigset_t *));
extern int unblock_trapped_signals PARAMS((sigset_t *));
#endif /* _SIG_H_ */