/* Special use of signals internally.  Linux version.

   Copyright (C) 2014-2018 Free Software Foundation, Inc.

   This file is part of the GNU C Library.

   The GNU C Library is free software; you can redistribute it and/or

   modify it under the terms of the GNU Lesser General Public

   License as published by the Free Software Foundation; either

   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library 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

   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public

   License along with the GNU C Library; if not, see

   <http://www.gnu.org/licenses/>.  */

#ifndef __INTERNAL_SIGNALS_H

# define __INTERNAL_SIGNALS_H

#include <signal.h>

#include <sigsetops.h>

#include <stdbool.h>

#include <sysdep.h>

/* The signal used for asynchronous cancelation.  */

#define SIGCANCEL       __SIGRTMIN

/* Signal needed for the kernel-supported POSIX timer implementation.

   We can reuse the cancellation signal since we can distinguish

   cancellation from timer expirations.  */

#define SIGTIMER        SIGCANCEL

/* Signal used to implement the setuid et.al. functions.  */

#define SIGSETXID       (__SIGRTMIN + 1)

/* Return is sig is used internally.  */

static inline bool

__is_internal_signal (int sig)

{

  return (sig == SIGCANCEL) || (sig == SIGSETXID);

}

/* Remove internal glibc signal from the mask.  */

static inline void

__clear_internal_signals (sigset_t *set)

{

  __sigdelset (set, SIGCANCEL);

  __sigdelset (set, SIGSETXID);

}

#define SIGALL_SET \

  ((__sigset_t) { .__val = {[0 ...  _SIGSET_NWORDS-1 ] =  -1 } })

/* Block all signals, including internal glibc ones.  */

static inline int

__libc_signal_block_all (sigset_t *set)

{

  INTERNAL_SYSCALL_DECL (err);

  return INTERNAL_SYSCALL (rt_sigprocmask, err, 4, SIG_BLOCK, &SIGALL_SET,

			   set, _NSIG / 8);

}

/* Block all application signals (excluding internal glibc ones).  */

static inline int

__libc_signal_block_app (sigset_t *set)

{

  sigset_t allset = SIGALL_SET;

  __clear_internal_signals (&allset);

  INTERNAL_SYSCALL_DECL (err);

  return INTERNAL_SYSCALL (rt_sigprocmask, err, 4, SIG_BLOCK, &allset, set,

			   _NSIG / 8);

}

/* Restore current process signal mask.  */

static inline int

__libc_signal_restore_set (const sigset_t *set)

{

  INTERNAL_SYSCALL_DECL (err);

  return INTERNAL_SYSCALL (rt_sigprocmask, err, 4, SIG_SETMASK, set, NULL,

			   _NSIG / 8);

}

/* Used to communicate with signal handler.  */

extern struct xid_command *__xidcmd attribute_hidden;

#endif