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/*        $NetBSD: dirent.h,v 1.29 2015/02/26 02:05:54 dholland Exp $        */
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/*-
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 * Copyright (c) 1989, 1993
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 *        The Regents of the University of California.  All rights reserved.
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 *
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 * Redistribution and use in source and binary forms, with or without
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 * modification, are permitted provided that the following conditions
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 * are met:
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 * 1. Redistributions of source code must retain the above copyright
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 *    notice, this list of conditions and the following disclaimer.
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 * 2. Redistributions in binary form must reproduce the above copyright
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 *    notice, this list of conditions and the following disclaimer in the
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 *    documentation and/or other materials provided with the distribution.
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 * 3. Neither the name of the University nor the names of its contributors
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 *    may be used to endorse or promote products derived from this software
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 *    without specific prior written permission.
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 *
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 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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 * SUCH DAMAGE.
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 *
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 *        @(#)dirent.h        8.3 (Berkeley) 8/10/94
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 */
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#ifndef _SYS_DIRENT_H_
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#define _SYS_DIRENT_H_
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#include <sys/featuretest.h>
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/*
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 * The dirent structure defines the format of directory entries returned by
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 * the getdents(2) system call.
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 *
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 * A directory entry has a struct dirent at the front of it, containing its
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 * inode number, the length of the entry, and the length of the name
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 * contained in the entry.  These are followed by the name padded to
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 * _DIRENT_ALIGN() byte boundary with null bytes.  All names are guaranteed
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 * NUL terminated.  The maximum length of a name in a directory is MAXNAMLEN.
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 */
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struct dirent {
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        ino_t d_fileno;                        /* file number of entry */
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        uint16_t d_reclen;                /* length of this record */
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        uint16_t d_namlen;                /* length of string in d_name */
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        uint8_t  d_type;                 /* file type, see below */
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#if defined(_NETBSD_SOURCE)
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#define        MAXNAMLEN        511                /* must be kept in sync with NAME_MAX */
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        char        d_name[MAXNAMLEN + 1];        /* name must be no longer than this */
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#else
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        char        d_name[511 + 1];        /* name must be no longer than this */
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#endif
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};
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#if defined(_NETBSD_SOURCE)
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/*
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 * File types
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 */
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#define        DT_UNKNOWN         0
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#define        DT_FIFO                 1
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#define        DT_CHR                 2
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#define        DT_DIR                 4
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#define        DT_BLK                 6
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#define        DT_REG                 8
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#define        DT_LNK                10
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#define        DT_SOCK                12
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#define        DT_WHT                14
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/*
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 * Caution: the following macros are used by the ufs/ffs code on ffs's
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 * struct direct as well as the exposed struct dirent. The two
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 * structures are not the same, so it's important (until ufs is fixed,
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 * XXX) that the macro definitions remain type-polymorphic.
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 */
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/*
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 * The _DIRENT_ALIGN macro returns the alignment of struct dirent.
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 * struct direct and struct dirent12 used 4 byte alignment but
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 * struct dirent uses 8.
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 */
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#define _DIRENT_ALIGN(dp) (sizeof((dp)->d_fileno) - 1)
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/*
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 * The _DIRENT_NAMEOFF macro returns the offset of the d_name field in
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 * struct dirent
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 */
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#if __GNUC_PREREQ__(4, 0)
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#define        _DIRENT_NAMEOFF(dp)        __builtin_offsetof(__typeof__(*(dp)), d_name)
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#else
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#define _DIRENT_NAMEOFF(dp) \
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    ((char *)(void *)&(dp)->d_name - (char *)(void *)dp)
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#endif
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/*
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 * The _DIRENT_RECLEN macro gives the minimum record length which will hold
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 * a name of size "namlen".  This requires the amount of space in struct dirent
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 * without the d_name field, plus enough space for the name with a terminating
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 * null byte (namlen+1), rounded up to a the appropriate byte boundary.
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 */
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#define _DIRENT_RECLEN(dp, namlen) \
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    ((_DIRENT_NAMEOFF(dp) + (namlen) + 1 + _DIRENT_ALIGN(dp)) & \
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    ~_DIRENT_ALIGN(dp))
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/*
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 * The _DIRENT_SIZE macro returns the minimum record length required for
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 * name name stored in the current record.
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 */
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#define        _DIRENT_SIZE(dp) _DIRENT_RECLEN(dp, (dp)->d_namlen)
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/*
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 * The _DIRENT_NEXT macro advances to the next dirent record.
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 */
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#define _DIRENT_NEXT(dp) ((void *)((char *)(void *)(dp) + (dp)->d_reclen))
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/*
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 * The _DIRENT_MINSIZE returns the size of an empty (invalid) record.
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 */
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#define _DIRENT_MINSIZE(dp) _DIRENT_RECLEN(dp, 0)
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/*
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 * Convert between stat structure types and directory types.
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 */
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#define        IFTODT(mode)        (((mode) & 0170000) >> 12)
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#define        DTTOIF(dirtype)        ((dirtype) << 12)
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#endif
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#endif        /* !_SYS_DIRENT_H_ */