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/* vi: set sw=4 ts=4: */
/*
* ext_attr.c --- extended attribute blocks
*
* Copyright (C) 2001 Andreas Gruenbacher, <a.gruenbacher@computer.org>
*
* Copyright (C) 2002 Theodore Ts'o.
*
* %Begin-Header%
* This file may be redistributed under the terms of the GNU Public
* License.
* %End-Header%
*/
#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <time.h>
#include "ext2_fs.h"
#include "ext2_ext_attr.h"
#include "ext2fs.h"
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;
#if BB_BIG_ENDIAN
if ((fs->flags & (EXT2_FLAG_SWAP_BYTES|
EXT2_FLAG_SWAP_BYTES_READ)) != 0)
ext2fs_swap_ext_attr(buf, buf, fs->blocksize, 1);
#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;
if (BB_BIG_ENDIAN && ((fs->flags & EXT2_FLAG_SWAP_BYTES) ||
(fs->flags & EXT2_FLAG_SWAP_BYTES_WRITE))) {
retval = ext2fs_get_mem(fs->blocksize, &buf);
if (retval)
return retval;
write_buf = buf;
ext2fs_swap_ext_attr(buf, inbuf, fs->blocksize, 1);
} else
write_buf = (char *) inbuf;
retval = io_channel_write_blk(fs->io, block, 1, write_buf);
if (buf)
ext2fs_free_mem(&buf);
if (!retval)
ext2fs_mark_changed(fs);
return retval;
}
/*
* This function adjusts the reference count of the EA block.
*/
errcode_t ext2fs_adjust_ea_refcount(ext2_filsys fs, blk_t blk,
char *block_buf, int adjust,
__u32 *newcount)
{
errcode_t retval;
struct ext2_ext_attr_header *header;
char *buf = 0;
if ((blk >= fs->super->s_blocks_count) ||
(blk < fs->super->s_first_data_block))
return EXT2_ET_BAD_EA_BLOCK_NUM;
if (!block_buf) {
retval = ext2fs_get_mem(fs->blocksize, &buf);
if (retval)
return retval;
block_buf = buf;
}
retval = ext2fs_read_ext_attr(fs, blk, block_buf);
if (retval)
goto errout;
header = (struct ext2_ext_attr_header *) block_buf;
header->h_refcount += adjust;
if (newcount)
*newcount = header->h_refcount;
retval = ext2fs_write_ext_attr(fs, blk, block_buf);
if (retval)
goto errout;
errout:
if (buf)
ext2fs_free_mem(&buf);
return retval;
}
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