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/* vi: set sw=4 ts=4: */
/*
* dirblock.c --- directory block routines.
*
* Copyright (C) 1995, 1996 Theodore Ts'o.
*
* %Begin-Header%
* This file may be redistributed under the terms of the GNU Public
* License.
* %End-Header%
*/
#include <stdio.h>
#if HAVE_UNISTD_H
#include <unistd.h>
#endif
#include <string.h>
#include <time.h>
#include "ext2_fs.h"
#include "ext2fs.h"
errcode_t ext2fs_read_dir_block2(ext2_filsys fs, blk_t block,
void *buf, int flags EXT2FS_ATTR((unused)))
{
errcode_t retval;
char *p, *end;
struct ext2_dir_entry *dirent;
unsigned int name_len, rec_len;
#if BB_BIG_ENDIAN
unsigned int do_swap;
#endif
retval = io_channel_read_blk(fs->io, block, 1, buf);
if (retval)
return retval;
#if BB_BIG_ENDIAN
do_swap = (fs->flags & (EXT2_FLAG_SWAP_BYTES|
EXT2_FLAG_SWAP_BYTES_READ)) != 0;
#endif
p = (char *) buf;
end = (char *) buf + fs->blocksize;
while (p < end-8) {
dirent = (struct ext2_dir_entry *) p;
#if BB_BIG_ENDIAN
if (do_swap) {
dirent->inode = ext2fs_swab32(dirent->inode);
dirent->rec_len = ext2fs_swab16(dirent->rec_len);
dirent->name_len = ext2fs_swab16(dirent->name_len);
}
#endif
name_len = dirent->name_len;
#ifdef WORDS_BIGENDIAN
if (flags & EXT2_DIRBLOCK_V2_STRUCT)
dirent->name_len = ext2fs_swab16(dirent->name_len);
#endif
rec_len = dirent->rec_len;
if ((rec_len < 8) || (rec_len % 4)) {
rec_len = 8;
retval = EXT2_ET_DIR_CORRUPTED;
}
if (((name_len & 0xFF) + 8) > dirent->rec_len)
retval = EXT2_ET_DIR_CORRUPTED;
p += rec_len;
}
return retval;
}
errcode_t ext2fs_read_dir_block(ext2_filsys fs, blk_t block,
void *buf)
{
return ext2fs_read_dir_block2(fs, block, buf, 0);
}
errcode_t ext2fs_write_dir_block2(ext2_filsys fs, blk_t block,
void *inbuf, int flags EXT2FS_ATTR((unused)))
{
#if BB_BIG_ENDIAN
int do_swap = 0;
errcode_t retval;
char *p, *end;
char *buf = NULL;
struct ext2_dir_entry *dirent;
if ((fs->flags & EXT2_FLAG_SWAP_BYTES) ||
(fs->flags & EXT2_FLAG_SWAP_BYTES_WRITE))
do_swap = 1;
#ifndef WORDS_BIGENDIAN
if (!do_swap)
return io_channel_write_blk(fs->io, block, 1, (char *) inbuf);
#endif
retval = ext2fs_get_mem(fs->blocksize, &buf);
if (retval)
return retval;
memcpy(buf, inbuf, fs->blocksize);
p = buf;
end = buf + fs->blocksize;
while (p < end) {
dirent = (struct ext2_dir_entry *) p;
if ((dirent->rec_len < 8) ||
(dirent->rec_len % 4)) {
ext2fs_free_mem(&buf);
return EXT2_ET_DIR_CORRUPTED;
}
p += dirent->rec_len;
if (do_swap) {
dirent->inode = ext2fs_swab32(dirent->inode);
dirent->rec_len = ext2fs_swab16(dirent->rec_len);
dirent->name_len = ext2fs_swab16(dirent->name_len);
}
#ifdef WORDS_BIGENDIAN
if (flags & EXT2_DIRBLOCK_V2_STRUCT)
dirent->name_len = ext2fs_swab16(dirent->name_len);
#endif
}
retval = io_channel_write_blk(fs->io, block, 1, buf);
ext2fs_free_mem(&buf);
return retval;
#else
return io_channel_write_blk(fs->io, block, 1, (char *) inbuf);
#endif
}
errcode_t ext2fs_write_dir_block(ext2_filsys fs, blk_t block,
void *inbuf)
{
return ext2fs_write_dir_block2(fs, block, inbuf, 0);
}
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