/* Copyright (C) 2009-2018 Free Software Foundation, Inc.

   This file is part of the GNU C Library.

   Contributed by Ulrich Drepper <drepper@redhat.com>, 2009.

   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/>.  */

#include <errno.h>

#include <signal.h>

#include <string.h>

#include <unistd.h>

#include <pthreadP.h>

#include <tls.h>

#include <sysdep.h>

int

pthread_sigqueue (pthread_t threadid, int signo, const union sigval value)

{

#ifdef __NR_rt_tgsigqueueinfo

  struct pthread *pd = (struct pthread *) threadid;

  /* Make sure the descriptor is valid.  */

  if (DEBUGGING_P && INVALID_TD_P (pd))

    /* Not a valid thread handle.  */

    return ESRCH;

  /* Force load of pd->tid into local variable or register.  Otherwise

     if a thread exits between ESRCH test and tgkill, we might return

     EINVAL, because pd->tid would be cleared by the kernel.  */

  pid_t tid = atomic_forced_read (pd->tid);

  if (__glibc_unlikely (tid <= 0))

    /* Not a valid thread handle.  */

    return ESRCH;

  /* Disallow sending the signal we use for cancellation, timers,

     for the setxid implementation.  */

  if (signo == SIGCANCEL || signo == SIGTIMER || signo == SIGSETXID)

    return EINVAL;

  pid_t pid = getpid ();

  /* Set up the siginfo_t structure.  */

  siginfo_t info;

  memset (&info, '\0', sizeof (siginfo_t));

  info.si_signo = signo;

  info.si_code = SI_QUEUE;

  info.si_pid = pid;

  info.si_uid = getuid ();

  info.si_value = value;

  /* We have a special syscall to do the work.  */

  INTERNAL_SYSCALL_DECL (err);

  int val = INTERNAL_SYSCALL_CALL (rt_tgsigqueueinfo, err, pid, tid, signo,

				   &info;;

  return (INTERNAL_SYSCALL_ERROR_P (val, err)

	  ? INTERNAL_SYSCALL_ERRNO (val, err) : 0);

#else

  return ENOSYS;

#endif

}