sysctl_fsid.c   [plain text]


/*
 * Copyright (c) 2000-2006 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_LICENSE_HEADER_START@
 *
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this
 * file.
 *
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
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 * @APPLE_LICENSE_HEADER_END@
 */

#include <string.h>
#include <sys/mount.h>
#include <sys/sysctl.h>

#include "sysctl_fsid.h"

int
sysctl_fsid(int op, fsid_t *fsid, void *oldp, size_t *oldlenp, void *newp,
    size_t newlen)
{
	int ctlname[CTL_MAXNAME+2];
	size_t ctllen;
	const char *sysstr = "vfs.generic.ctlbyfsid";
	struct vfsidctl vc;

	ctllen = CTL_MAXNAME+2;
	if (sysctlnametomib(sysstr, ctlname, &ctllen) == -1)
		return (-1);
	ctlname[ctllen] = op;

	memset(&vc, 0, sizeof(vc));
	vc.vc_vers = VFS_CTL_VERS1;
	vc.vc_fsid = *fsid;
	vc.vc_ptr = newp;
	vc.vc_len = newlen;
	return (sysctl(ctlname, ctllen + 1, oldp, oldlenp, &vc, sizeof(vc)));
}