slimbootloader/BootloaderCommonPkg/Library/Ext23Lib/Ext2FsDir.h

/** @file
  Copyright (c) 1982, 1986, 1989, 1993
     The Regents of the University of California.  All rights reserved.
  (c) UNIX System Laboratories, Inc.
  All or some portions of this file are derived from material licensed
  to the University of California by American Telephone and Telegraph
  Co. or Unix System Laboratories, Inc. and are reproduced herein with
  the permission of UNIX System Laboratories, Inc.

  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 University 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 REGENTS 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 REGENTS 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.

  @file dir.h    8.4 (Berkeley) 8/10/94
  Modified for ext2fs by Manuel Bouyer.

  Copyright (c) 1997 Manuel Bouyer.

  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.

  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.

  @file dir.h    8.4 (Berkeley) 8/10/94
  Modified for ext2fs by Manuel Bouyer.
 **/

#ifndef _UFS_EXT2FS_EXT2FS_DIR_H_
#define    _UFS_EXT2FS_EXT2FS_DIR_H_

/**
  Theoretically, directories can be more than 2Gb in length, however, in
  practice this seems unlikely. So, we define the type doff_t as a 32-bit
  quantity to keep down the cost of doing lookup on a 32-bit machine.
**/
#define    DIROFFSET               INT32
#define    EXT2FS_MAXDIRSIZE    INT32_MAX

/**
  A directory consists of some number of blocks of e2fs_bsize bytes.

  Each block contains some number of directory entry
  structures, which are of variable length.  Each directory entry has
  a struct direct at the front of it, containing its inode number,
  the length of the entry, and the length of the name contained in
  the entry.  These are followed by the name padded to a 4 byte boundary
  with null bytes.  All names are guaranteed null terminated.
  The maximum length of a name in a directory is EXT2FS_MAXNAMLEN.

  The macro EXT2FS_DIRSIZ(fmt, dp) gives the amount of space required to
  represent a directory entry.  Free space in a directory is represented by
  entries which have dp->Ext2DirectRecLen > DIRSIZ(fmt, dp).  All d2fs_bsize bytes
  in a directory block are claimed by the directory entries.  This
  usually results in the last entry in a directory having a large
  dp->Ext2DirectRecLen.  When entries are deleted from a directory, the
  space is returned to the previous entry in the same directory
  block by increasing its dp->Ext2DirectRecLen.  If the first entry of
  a directory block is free, then its dp->Ext2DirectInodeNumber is set to 0.
  Entries other than the first in a directory do not normally have
  dp->Ext2DirectInodeNumber set to 0.
  Ext2 rev 0 has a 16 bits Ext2DirectNameLen. For Ext2 vev 1 this has been split
  into a 8 bits Ext2DirectNameLen and 8 bits Ext2DirectType (looks like ffs, isnt't it ? :)
  It's safe to use this for rev 0 as well because all ext2 are little-endian.
 **/

#define    EXT2FS_MAXNAMLEN    255

typedef struct {
  UINT32 Ext2DirectInodeNumber;             // inode number of entry
  UINT16 Ext2DirectRecLen;                  // length of this record
  UINT8 Ext2DirectNameLen;                  // length of string in d_name
  UINT8 Ext2DirectType;                     // file type
  CHAR8 Ext2DirectName[EXT2FS_MAXNAMLEN];   // name with length<=EXT2FS_MAXNAMLEN
} EXT2FS_DIRECT;

//
// Ext2 directory file types (not the same as FFS. Sigh.)
//
#define EXT2_FT_UNKNOWN         0
#define EXT2_FT_REG_FILE        1
#define EXT2_FT_DIR             2
#define EXT2_FT_CHRDEV          3
#define EXT2_FT_BLKDEV          4
#define EXT2_FT_FIFO            5
#define EXT2_FT_SOCK            6
#define EXT2_FT_SYMLINK         7

#define EXT2_FT_MAX             8

#define E2IFTODT(mode)    (((mode) & 0170000) >> 12)


/**
  The EXT2FS_DIRSIZ macro gives the minimum record length which will hold
  the directory entryfor a name len "len" (without the terminating null byte).
  This requires the amount of space in struct direct
  without the d_name field, plus enough space for the name without a
  terminating null byte, rounded up to a 4 byte boundary.
**/
#define EXT2FS_DIRSIZ(len)    roundup2(8 + len, 4)


#endif // !_UFS_EXT2FS_EXT2FS_DIR_H_