port/gen/mkdev.c

	mkdev.c revision 7c478bd95313f5f23a4c958a745db2134aa03244
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#pragma ident   "%Z%%M% %I% %E% SMI"

/*  Copyright (c) 1988 AT&T */
/*    All Rights Reserved   */


#include "synonyms.h"
#include <sys/types.h>
#include <sys/mkdev.h>
#include <errno.h>

/*
 * Create a formatted device number
 */
dev_t
__makedev(const int version, const major_t majdev, const minor_t mindev)
{
    dev_t devnum;
    switch (version) {
    case OLDDEV:
        if (majdev > OMAXMAJ || mindev > OMAXMIN) {
            errno = EINVAL;
            return ((o_dev_t)NODEV);
        }
        devnum = ((majdev << ONBITSMINOR) | mindev);
        break;

    case NEWDEV:
#if MAXMAJ != 0xfffffffful  /* assumes major_t == uint32_t */
        if (majdev > MAXMAJ) {
            errno = EINVAL;
            return (NODEV);
        }
#endif
#if MAXMIN != 0xfffffffful  /* assumes minor_t == uint32_t */
        if (mindev > MAXMIN) {
            errno = EINVAL;
            return (NODEV);
        }
#endif
        if ((devnum = (((dev_t)majdev << NBITSMINOR) |
            mindev)) == NODEV) {
            errno = EINVAL;
            return (NODEV);
        }
        break;

    default:
        errno = EINVAL;
        return (NODEV);
    }

    return (devnum);
}

/*
 * Return major number part of formatted device number
 */
major_t
__major(const int version, const dev_t devnum)
{
    major_t maj;

    switch (version) {
    case OLDDEV:
        maj = (devnum >> ONBITSMINOR);
        if (devnum == NODEV || maj > OMAXMAJ) {
            errno = EINVAL;
            return ((major_t)NODEV);
        }
        break;

    case NEWDEV:
        maj = (devnum >> NBITSMINOR);
        if (devnum == NODEV) {
            errno = EINVAL;
            return ((major_t)NODEV);
        }
#if MAXMAJ != 0xfffffffful  /* assumes major_t == uint32_t */
        if (maj > MAXMAJ) {
            errno = EINVAL;
            return ((major_t)NODEV);
        }
#endif
        break;

    default:
        errno = EINVAL;
        return ((major_t)NODEV);
    }

    return (maj);
}


/*
 * Return minor number part of formatted device number
 */
minor_t
__minor(const int version, const dev_t devnum)
{
    switch (version) {
    case OLDDEV:
        if (devnum == NODEV) {
            errno = EINVAL;
            return ((minor_t)NODEV);
        }
        return (devnum & OMAXMIN);

    case NEWDEV:
        if (devnum == NODEV) {
            errno = EINVAL;
            return ((minor_t)NODEV);
        }
        return (devnum & MAXMIN);

    default:
        errno = EINVAL;
        return ((minor_t)NODEV);
    }
}