133 lines
3.1 KiB
C
133 lines
3.1 KiB
C
/* 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);
|
|
}
|