text: /*
   * Copyright (c) 2007 The DragonFly Project.  All rights reserved.
   * 
   * This code is derived from software contributed to The DragonFly Project
   * by Matthew Dillon <dillon@backplane.com>
   * 
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   * 
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in
   *    the documentation and/or other materials provided with the
   *    distribution.
   * 3. Neither the name of The DragonFly Project nor the names of its
   *    contributors may be used to endorse or promote products derived
   *    from this software without specific, prior written permission.
   * 
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
   * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
   * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
   * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
   * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
   * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
   * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
   * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
   * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
   * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   * SUCH DAMAGE.
   */
  /*
   * Install a signal handler for SIGTERM which shuts down the virtual kernel
   */
  
  #include <sys/types.h>
  #include <sys/systm.h>
  #include <sys/reboot.h>
  #include <sys/kernel.h>
  #include <sys/kthread.h>
  #include <sys/interrupt.h>
  #include <sys/bus.h>
  #include <ddb/ddb.h>
  
  #include <sys/thread2.h>
  
  #include <machine/trap.h>
  #include <machine/md_var.h>
  #include <machine/segments.h>
  #include <machine/cpu.h>
  
  #include <err.h>
  #include <signal.h>
  #include <unistd.h>
  
  static void shutdownsig(int signo);
  static void shutdown_intr(void *arg __unused, void *frame __unused);
  
  static
  void
  initshutdown(void *arg __unused)
  {
  	struct sigaction sa;
  
  	bzero(&sa, sizeof(sa));
  	sigemptyset(&sa.sa_mask);
  	sa.sa_flags |= SA_NODEFER;
  	sa.sa_handler = shutdownsig;
  	sigaction(SIGTERM, &sa, NULL);
  
  	register_int_virtual(2, shutdown_intr, NULL, "shutdown", NULL,
  	    INTR_MPSAFE);
  }
  
  static
  void
  shutdownsig(int signo)
  {
  	signalintr(2);
  }
  
  SYSINIT(initshutdown, SI_BOOT2_PROC0, SI_ORDER_ANY, 
  	initshutdown, NULL); 
  
  /*
   * DragonFly-safe interrupt thread.  We are the only handler on interrupt
   * #2 so we can just steal the thread's context forever.
   */
  static
  void
  shutdown_intr(void *arg __unused, void *frame __unused)
  {
  	kprintf("Caught SIGTERM from host system. Shutting down...\n");
  	if (initproc != NULL) {
  		ksignal(initproc, SIGUSR2);
  	} else {
  		reboot(RB_POWEROFF);
  	}	
  }
  
  