text: /*-
   * Copyright (c) 2001 Marcel Moolenaar
   * All rights reserved.
   *
   * 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 
   *    in this position and unchanged.
   * 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. The name of the author may not be used to endorse or promote products
   *    derived from this software without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
   *
   * $FreeBSD: src/sys/compat/linux/linux_sysctl.c,v 1.2.2.1 2001/10/21 03:57:35 marcel Exp $
   * $DragonFly: src/sys/emulation/linux/linux_sysctl.c,v 1.9 2006/12/23 00:27:02 swildner Exp $
   */
  
  #include "opt_compat.h"
  
  #include <sys/param.h>
  #include <sys/systm.h>
  #include <sys/proc.h>
  #include <sys/sysproto.h>
  
  #include <sys/mplock2.h>
  
  #include <arch_linux/linux.h>
  #include <arch_linux/linux_proto.h>
  #include "linux_util.h"
  
  #define	LINUX_CTL_KERN		1
  #define	LINUX_CTL_VM		2
  #define	LINUX_CTL_NET		3
  #define	LINUX_CTL_PROC		4
  #define	LINUX_CTL_FS		5
  #define	LINUX_CTL_DEBUG		6
  #define	LINUX_CTL_DEV		7
  #define	LINUX_CTL_BUS		8
  
  /* CTL_KERN names */
  #define	LINUX_KERN_OSTYPE	1
  #define	LINUX_KERN_OSRELEASE	2
  #define	LINUX_KERN_OSREV	3
  #define	LINUX_KERN_VERSION	4
  
  static int
  handle_string(struct l___sysctl_args *la, char *value)
  {
  	int error;
  
  	if (la->oldval != NULL) {
  		l_int len = strlen(value);
  		error = copyout(value, la->oldval, len + 1);
  		if (!error && la->oldlenp != NULL)
  			error = copyout(&len, la->oldlenp, sizeof(len));
  		if (error)
  			return (error);
  	}
  
  	if (la->newval != NULL)
  		return (ENOTDIR);
  
  	return (0);
  }
  
  /*
   * MPALMOSTSAFE
   */
  int
  sys_linux_sysctl(struct linux_sysctl_args *args)
  {
  	struct l___sysctl_args la;
  	l_int *mib;
  	int error, i;
  
  	error = copyin((caddr_t)args->args, &la, sizeof(la));
  	if (error)
  		return (error);
  
  	if (la.nlen <= 0 || la.nlen > LINUX_CTL_MAXNAME)
  		return (ENOTDIR);
  
  	mib = kmalloc(la.nlen * sizeof(l_int), M_TEMP, M_WAITOK);
  	error = copyin(la.name, mib, la.nlen * sizeof(l_int));
  	if (error) {
  		kfree(mib, M_TEMP);
  		return (error);
  	}
  
  	get_mplock();
  
  	switch (mib[0]) {
  	case LINUX_CTL_KERN:
  		if (la.nlen < 2) {
  			error = ENOTDIR;
  			break;
  		}
  
  		switch (mib[1]) {
  		case LINUX_KERN_VERSION:
  			error = handle_string(&la, version);
  			break;
  		default:
  			error = ENOTDIR;
  			break;
  		}
  		break;
  	default:
  		error = ENOTDIR;
  		break;
  	}
  	rel_mplock();
  
  	if (error == ENOTDIR && mib) {
  		kprintf("linux: sysctl: unhandled name=");
  		for (i = 0; i < la.nlen; i++)
  			kprintf("%c%d", (i) ? ',' : '{', mib[i]);
  		kprintf("}\n");
  	}
  	if (mib)
  		kfree(mib, M_TEMP);
  	return (error);
  }
  