hurd/hurdkill.c

   1 /* Copyright (C) 1991, 92, 93, 94, 95, 96, 97 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, write to the Free
  16    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  17    02111-1307 USA.  */
  18
  19 #include <errno.h>
  20 #include <sys/types.h>
  21 #include <signal.h>
  22 #include <hurd.h>
  23 #include <hurd/port.h>
  24 #include <hurd/signal.h>
  25 #include <hurd/msg.h>
  26
  27 /* Send a `sig_post' RPC to process number PID.  If PID is zero,
  28    send the message to all processes in the current process's process group.
  29    If PID is < -1, send SIG to all processes in process group - PID.
  30    SIG and REFPORT are passed along in the request message.  */
  31 error_t
  32 _hurd_sig_post (pid_t pid, int sig, mach_port_t arg_refport)
  33 {
  34   int delivered = 0;            /* Set when we deliver any signal.  */
  35   error_t err;
  36   mach_port_t proc;
  37   struct hurd_userlink ulink;
  38
  39   inline void kill_pid (pid_t pid) /* Kill one PID.  */
  40     {
  41       err = HURD_MSGPORT_RPC (__proc_getmsgport (proc, pid, &msgport),
  42                               (refport = arg_refport, 0), 0,
  43                               /* If no message port we cannot send signals.  */
  44                               msgport == MACH_PORT_NULL ? EPERM :
  45                               __msg_sig_post (msgport, sig, 0, refport));
  46       if (! err)
  47         delivered = 1;
  48     }
  49
  50   proc = _hurd_port_get (&_hurd_ports[INIT_PORT_PROC], &ulink);
  51
  52   if (pid <= 0)
  53     {
  54       /* Send SIG to each process in pgrp (- PID).  */
  55       mach_msg_type_number_t npids = 10, i;
  56       pid_t pidsbuf[10], *pids = pidsbuf;
  57
  58       err = __proc_getpgrppids (proc, - pid, &pids, &npids);
  59       if (!err)
  60         {
  61           int self = 0;
  62           for (i = 0; i < npids; ++i)
  63             if (pids[i] == _hurd_pid)
  64               /* We must do ourselves last so we are not suspended
  65                  and fail to suspend the other processes in the pgrp.  */
  66               self = 1;
  67             else
  68               {
  69                 kill_pid (pids[i]);
  70                 if (err == ESRCH)
  71                   /* The process died already.  Ignore it.  */
  72                   err = 0;
  73               }
  74           if (pids != pidsbuf)
  75             __vm_deallocate (__mach_task_self (),
  76                              (vm_address_t) pids, npids * sizeof (pids[0]));
  77
  78           if (self)
  79             kill_pid (_hurd_pid);
  80         }
  81     }
  82   else
  83     kill_pid (pid);
  84
  85   _hurd_port_free (&_hurd_ports[INIT_PORT_PROC], &ulink, proc);
  86
  87   /* If we delivered no signals, but ERR is clear, this must mean that
  88      every kill_pid call failed with ESRCH, meaning all the processes in
  89      the pgrp died between proc_getpgrppids and kill_pid; in that case we
  90      fail with ESRCH.  */
  91   return delivered ? 0 : err ?: ESRCH;
  92 }
  93 weak_alias (_hurd_sig_post, hurd_sig_post)