e2fsprogs/lib/ext2fs/ext_attr.c

99 lines
2.6 KiB
C

/*
* ext_attr.c --- extended attribute blocks
*
* Copyright (C) Andreas Gruenbacher, <a.gruenbacher@computer.org>
*
* %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 "ext2_ext_attr.h"
#include "ext2fs.h"
#ifdef EXT2FS_ENABLE_SWAPFS
void ext2fs_swap_ext_attr(ext2_filsys fs, char *to, char *from)
{
struct ext2_ext_attr_header *from_header =
(struct ext2_ext_attr_header *)from;
struct ext2_ext_attr_header *to_header =
(struct ext2_ext_attr_header *)to;
struct ext2_ext_attr_entry *from_entry, *to_entry;
char *from_end = (char *)from_header + fs->blocksize;
int n;
if (to_header != from_header)
memcpy(to_header, from_header, fs->blocksize);
to_header->h_magic = ext2fs_swab32(from_header->h_magic);
to_header->h_blocks = ext2fs_swab32(from_header->h_blocks);
to_header->h_refcount = ext2fs_swab32(from_header->h_refcount);
for (n=0; n<4; n++)
to_header->h_reserved[n] =
ext2fs_swab32(from_header->h_reserved[n]);
from_entry = (struct ext2_ext_attr_entry *)(from_header+1);
to_entry = (struct ext2_ext_attr_entry *)(to_header+1);
while ((char *)from_entry < from_end && *(__u32 *)from_entry) {
to_entry->e_value_offs =
ext2fs_swab16(from_entry->e_value_offs);
to_entry->e_value_block =
ext2fs_swab32(from_entry->e_value_block);
to_entry->e_value_size =
ext2fs_swab32(from_entry->e_value_size);
from_entry = EXT2_EXT_ATTR_NEXT(from_entry);
to_entry = EXT2_EXT_ATTR_NEXT(to_entry);
}
}
#endif
errcode_t ext2fs_read_ext_attr(ext2_filsys fs, blk_t block, void *buf)
{
errcode_t retval;
retval = io_channel_read_blk(fs->io, block, 1, buf);
if (retval)
return retval;
#ifdef EXT2FS_ENABLE_SWAPFS
if ((fs->flags & (EXT2_FLAG_SWAP_BYTES|
EXT2_FLAG_SWAP_BYTES_READ)) != 0)
ext2fs_swap_ext_attr(fs, buf, buf);
#endif
return 0;
}
errcode_t ext2fs_write_ext_attr(ext2_filsys fs, blk_t block, void *inbuf)
{
errcode_t retval;
char *write_buf;
char *buf = NULL;
#ifdef EXT2FS_ENABLE_SWAPFS
if ((fs->flags & EXT2_FLAG_SWAP_BYTES) ||
(fs->flags & EXT2_FLAG_SWAP_BYTES_WRITE)) {
retval = ext2fs_get_mem(fs->blocksize, (void **) &buf);
if (retval)
return retval;
write_buf = buf;
ext2fs_swap_ext_attr(fs, buf, inbuf);
} else
#endif
write_buf = (char *) inbuf;
retval = io_channel_write_blk(fs->io, block, 1, write_buf);
if (buf)
ext2fs_free_mem((void **) &buf);
if (!retval)
ext2fs_mark_changed(fs);
return retval;
}