/* Copyright (C) 1991-2018 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/>.  */

#include <errno.h>

#include <sys/types.h>

#include <signal.h>

#include <hurd.h>

#include <hurd/port.h>

#include <hurd/signal.h>

#include <hurd/msg.h>

/* Send a `sig_post' RPC to process number PID.  If PID is zero,

   send the message to all processes in the current process's process group.

   If PID is < -1, send SIG to all processes in process group - PID.

   SIG and REFPORT are passed along in the request message.  */

error_t

_hurd_sig_post (pid_t pid, int sig, mach_port_t arg_refport)

{

  int delivered = 0;		/* Set when we deliver any signal.  */

  error_t err;

  mach_port_t proc;

  struct hurd_userlink ulink;

  inline void kill_pid (pid_t pid) /* Kill one PID.  */

    {

      err = HURD_MSGPORT_RPC (__proc_getmsgport (proc, pid, &msgport),

			      (refport = arg_refport, 0), 0,

			      /* If no message port we cannot send signals.  */

			      msgport == MACH_PORT_NULL ? EPERM :

			      __msg_sig_post (msgport, sig, 0, refport));

      if (! err)

	delivered = 1;

    }

  proc = _hurd_port_get (&_hurd_ports[INIT_PORT_PROC], &ulink);

  if (pid <= 0)

    {

      /* Send SIG to each process in pgrp (- PID).  */

      mach_msg_type_number_t npids = 10, i;

      pid_t pidsbuf[10], *pids = pidsbuf;

      err = __proc_getpgrppids (proc, - pid, &pids, &npids);

      if (!err)

	{

	  int self = 0;

	  for (i = 0; i < npids; ++i)

	    if (pids[i] == _hurd_pid)

	      /* We must do ourselves last so we are not suspended

		 and fail to suspend the other processes in the pgrp.  */

	      self = 1;

	    else

	      {

		kill_pid (pids[i]);

		if (err == ESRCH)

		  /* The process died already.  Ignore it.  */

		  err = 0;

	      }

	  if (pids != pidsbuf)

	    __vm_deallocate (__mach_task_self (),

			     (vm_address_t) pids, npids * sizeof (pids[0]));

	  if (self)

	    kill_pid (_hurd_pid);

	}

    }

  else

    kill_pid (pid);

  _hurd_port_free (&_hurd_ports[INIT_PORT_PROC], &ulink, proc);

  /* If we delivered no signals, but ERR is clear, this must mean that

     every kill_pid call failed with ESRCH, meaning all the processes in

     the pgrp died between proc_getpgrppids and kill_pid; in that case we

     fail with ESRCH.  */

  return delivered ? 0 : err ?: ESRCH;

}

weak_alias (_hurd_sig_post, hurd_sig_post)