mirror of https://github.com/vitalif/e2fsprogs
315 lines
8.1 KiB
C
315 lines
8.1 KiB
C
/*
|
|
* block.c --- iterate over all blocks in an inode
|
|
*
|
|
* Copyright (C) 1993 Theodore Ts'o. This file may be redistributed
|
|
* under the terms of the GNU Public License.
|
|
*/
|
|
|
|
#include <stdio.h>
|
|
#include <string.h>
|
|
#include <unistd.h>
|
|
#include <stdlib.h>
|
|
#if HAVE_ERRNO_H
|
|
#include <errno.h>
|
|
#endif
|
|
|
|
#include <linux/ext2_fs.h>
|
|
|
|
#include "ext2fs.h"
|
|
|
|
struct block_context {
|
|
ext2_filsys fs;
|
|
int (*func)(ext2_filsys fs,
|
|
blk_t *blocknr,
|
|
int bcount,
|
|
void *private);
|
|
int bcount;
|
|
int bsize;
|
|
int flags;
|
|
errcode_t errcode;
|
|
char *ind_buf;
|
|
char *dind_buf;
|
|
char *tind_buf;
|
|
void *private;
|
|
};
|
|
|
|
static int block_iterate_ind(blk_t *ind_block, struct block_context *ctx)
|
|
{
|
|
int ret = 0, changed = 0;
|
|
int i, flags, limit;
|
|
blk_t *block_nr;
|
|
|
|
if (!(ctx->flags & BLOCK_FLAG_DEPTH_TRAVERSE))
|
|
ret = (*ctx->func)(ctx->fs, ind_block, -1, ctx->private);
|
|
if (!*ind_block || (ret & BLOCK_ABORT))
|
|
return ret;
|
|
if (*ind_block >= ctx->fs->super->s_blocks_count ||
|
|
*ind_block < ctx->fs->super->s_first_data_block) {
|
|
ctx->errcode = EXT2_ET_BAD_IND_BLOCK;
|
|
ret |= BLOCK_ERROR;
|
|
return ret;
|
|
}
|
|
ctx->errcode = io_channel_read_blk(ctx->fs->io, *ind_block,
|
|
1, ctx->ind_buf);
|
|
if (ctx->errcode) {
|
|
ret |= BLOCK_ERROR;
|
|
return ret;
|
|
}
|
|
limit = ctx->fs->blocksize >> 2;
|
|
if (ctx->fs->flags & EXT2_SWAP_BYTES) {
|
|
block_nr = (blk_t *) ctx->ind_buf;
|
|
for (i = 0; i < limit; i++, block_nr++)
|
|
*block_nr = ext2fs_swab32(*block_nr);
|
|
}
|
|
block_nr = (blk_t *) ctx->ind_buf;
|
|
if (ctx->flags & BLOCK_FLAG_APPEND) {
|
|
for (i = 0; i < limit; i++, ctx->bcount++, block_nr++) {
|
|
flags = (*ctx->func)(ctx->fs, block_nr, ctx->bcount,
|
|
ctx->private);
|
|
changed |= flags;
|
|
if (flags & BLOCK_ABORT) {
|
|
ret |= BLOCK_ABORT;
|
|
break;
|
|
}
|
|
}
|
|
} else {
|
|
for (i = 0; i < limit; i++, ctx->bcount++, block_nr++) {
|
|
if (*block_nr == 0)
|
|
continue;
|
|
flags = (*ctx->func)(ctx->fs, block_nr, ctx->bcount,
|
|
ctx->private);
|
|
changed |= flags;
|
|
if (flags & BLOCK_ABORT) {
|
|
ret |= BLOCK_ABORT;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
if (changed & BLOCK_CHANGED) {
|
|
if (ctx->fs->flags & EXT2_SWAP_BYTES) {
|
|
block_nr = (blk_t *) ctx->ind_buf;
|
|
for (i = 0; i < limit; i++, block_nr++)
|
|
*block_nr = ext2fs_swab32(*block_nr);
|
|
}
|
|
ctx->errcode = io_channel_write_blk(ctx->fs->io, *ind_block,
|
|
1, ctx->ind_buf);
|
|
if (ctx->errcode)
|
|
ret |= BLOCK_ERROR | BLOCK_ABORT;
|
|
}
|
|
if ((ctx->flags & BLOCK_FLAG_DEPTH_TRAVERSE) &&
|
|
!(ret & BLOCK_ABORT))
|
|
ret |= (*ctx->func)(ctx->fs, ind_block, -1, ctx->private);
|
|
return ret;
|
|
}
|
|
|
|
static int block_iterate_dind(blk_t *dind_block, struct block_context *ctx)
|
|
{
|
|
int ret = 0, changed = 0;
|
|
int i, flags, limit;
|
|
blk_t *block_nr;
|
|
|
|
if (!(ctx->flags & BLOCK_FLAG_DEPTH_TRAVERSE))
|
|
ret = (*ctx->func)(ctx->fs, dind_block, -2, ctx->private);
|
|
if (!*dind_block || (ret & BLOCK_ABORT))
|
|
return ret;
|
|
if (*dind_block >= ctx->fs->super->s_blocks_count ||
|
|
*dind_block < ctx->fs->super->s_first_data_block) {
|
|
ctx->errcode = EXT2_ET_BAD_DIND_BLOCK;
|
|
ret |= BLOCK_ERROR;
|
|
return ret;
|
|
}
|
|
ctx->errcode = io_channel_read_blk(ctx->fs->io, *dind_block,
|
|
1, ctx->dind_buf);
|
|
if (ctx->errcode) {
|
|
ret |= BLOCK_ERROR;
|
|
return ret;
|
|
}
|
|
limit = ctx->fs->blocksize >> 2;
|
|
if (ctx->fs->flags & EXT2_SWAP_BYTES) {
|
|
block_nr = (blk_t *) ctx->dind_buf;
|
|
for (i = 0; i < limit; i++, block_nr++)
|
|
*block_nr = ext2fs_swab32(*block_nr);
|
|
}
|
|
block_nr = (blk_t *) ctx->dind_buf;
|
|
if (ctx->flags & BLOCK_FLAG_APPEND) {
|
|
for (i = 0; i < limit; i++, block_nr++) {
|
|
flags = block_iterate_ind(block_nr, ctx);
|
|
changed |= flags;
|
|
if (flags & (BLOCK_ABORT | BLOCK_ERROR)) {
|
|
ret |= flags & (BLOCK_ABORT | BLOCK_ERROR);
|
|
break;
|
|
}
|
|
}
|
|
} else {
|
|
for (i = 0; i < limit; i++, block_nr++) {
|
|
if (*block_nr == 0)
|
|
continue;
|
|
flags = block_iterate_ind(block_nr, ctx);
|
|
changed |= flags;
|
|
if (flags & (BLOCK_ABORT | BLOCK_ERROR)) {
|
|
ret |= flags & (BLOCK_ABORT | BLOCK_ERROR);
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
if (changed & BLOCK_CHANGED) {
|
|
if (ctx->fs->flags & EXT2_SWAP_BYTES) {
|
|
block_nr = (blk_t *) ctx->dind_buf;
|
|
for (i = 0; i < limit; i++, block_nr++)
|
|
*block_nr = ext2fs_swab32(*block_nr);
|
|
}
|
|
ctx->errcode = io_channel_write_blk(ctx->fs->io, *dind_block,
|
|
1, ctx->dind_buf);
|
|
if (ctx->errcode)
|
|
ret |= BLOCK_ERROR | BLOCK_ABORT;
|
|
}
|
|
if ((ctx->flags & BLOCK_FLAG_DEPTH_TRAVERSE) &&
|
|
!(ret & BLOCK_ABORT))
|
|
ret |= (*ctx->func)(ctx->fs, dind_block, -2, ctx->private);
|
|
return ret;
|
|
}
|
|
|
|
static int block_iterate_tind(blk_t *tind_block, struct block_context *ctx)
|
|
{
|
|
int ret = 0, changed = 0;
|
|
int i, flags, limit;
|
|
blk_t *block_nr;
|
|
|
|
if (!(ctx->flags & BLOCK_FLAG_DEPTH_TRAVERSE))
|
|
ret = (*ctx->func)(ctx->fs, tind_block, -3, ctx->private);
|
|
if (!*tind_block || (ret & BLOCK_ABORT))
|
|
return ret;
|
|
if (*tind_block >= ctx->fs->super->s_blocks_count ||
|
|
*tind_block < ctx->fs->super->s_first_data_block) {
|
|
ctx->errcode = EXT2_ET_BAD_TIND_BLOCK;
|
|
ret |= BLOCK_ERROR;
|
|
return ret;
|
|
}
|
|
ctx->errcode = io_channel_read_blk(ctx->fs->io, *tind_block,
|
|
1, ctx->tind_buf);
|
|
if (ctx->errcode) {
|
|
ret |= BLOCK_ERROR;
|
|
return ret;
|
|
}
|
|
limit = ctx->fs->blocksize >> 2;
|
|
if (ctx->fs->flags & EXT2_SWAP_BYTES) {
|
|
block_nr = (blk_t *) ctx->tind_buf;
|
|
for (i = 0; i < limit; i++, block_nr++)
|
|
*block_nr = ext2fs_swab32(*block_nr);
|
|
}
|
|
block_nr = (blk_t *) ctx->tind_buf;
|
|
if (ctx->flags & BLOCK_FLAG_APPEND) {
|
|
for (i = 0; i < limit; i++, block_nr++) {
|
|
flags = block_iterate_dind(block_nr, ctx);
|
|
changed |= flags;
|
|
if (flags & (BLOCK_ABORT | BLOCK_ERROR)) {
|
|
ret |= flags & (BLOCK_ABORT | BLOCK_ERROR);
|
|
break;
|
|
}
|
|
}
|
|
} else {
|
|
for (i = 0; i < limit; i++, block_nr++) {
|
|
if (*block_nr == 0)
|
|
continue;
|
|
flags = block_iterate_dind(block_nr, ctx);
|
|
changed |= flags;
|
|
if (flags & (BLOCK_ABORT | BLOCK_ERROR)) {
|
|
ret |= flags & (BLOCK_ABORT | BLOCK_ERROR);
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
if (changed & BLOCK_CHANGED) {
|
|
if (ctx->fs->flags & EXT2_SWAP_BYTES) {
|
|
block_nr = (blk_t *) ctx->tind_buf;
|
|
for (i = 0; i < limit; i++, block_nr++)
|
|
*block_nr = ext2fs_swab32(*block_nr);
|
|
}
|
|
ctx->errcode = io_channel_write_blk(ctx->fs->io, *tind_block,
|
|
1, ctx->tind_buf);
|
|
if (ctx->errcode)
|
|
ret |= BLOCK_ERROR | BLOCK_ABORT;
|
|
}
|
|
if ((ctx->flags & BLOCK_FLAG_DEPTH_TRAVERSE) &&
|
|
!(ret & BLOCK_ABORT))
|
|
ret |= (*ctx->func)(ctx->fs, tind_block, -3, ctx->private);
|
|
|
|
return ret;
|
|
}
|
|
|
|
errcode_t ext2fs_block_iterate(ext2_filsys fs,
|
|
ino_t ino,
|
|
int flags,
|
|
char *block_buf,
|
|
int (*func)(ext2_filsys fs,
|
|
blk_t *blocknr,
|
|
int blockcnt,
|
|
void *private),
|
|
void *private)
|
|
{
|
|
int i;
|
|
int ret = 0;
|
|
struct block_context ctx;
|
|
blk_t blocks[EXT2_N_BLOCKS]; /* directory data blocks */
|
|
struct ext2_inode inode;
|
|
errcode_t retval;
|
|
|
|
EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
|
|
|
|
ret = ext2fs_get_blocks(fs, ino, blocks);
|
|
if (ret)
|
|
return ret;
|
|
|
|
ctx.fs = fs;
|
|
ctx.func = func;
|
|
ctx.private = private;
|
|
ctx.bcount = 0;
|
|
ctx.flags = flags;
|
|
if (block_buf) {
|
|
ctx.ind_buf = block_buf;
|
|
} else {
|
|
ctx.ind_buf = malloc(fs->blocksize * 3);
|
|
if (!ctx.ind_buf)
|
|
return ENOMEM;
|
|
}
|
|
ctx.dind_buf = ctx.ind_buf + fs->blocksize;
|
|
ctx.tind_buf = ctx.dind_buf + fs->blocksize;
|
|
|
|
for (i = 0; i < EXT2_NDIR_BLOCKS ; i++, ctx.bcount++) {
|
|
if (blocks[i] || (flags & BLOCK_FLAG_APPEND)) {
|
|
ret |= (*func)(fs, &blocks[i], ctx.bcount, private);
|
|
if (ret & BLOCK_ABORT)
|
|
goto abort;
|
|
}
|
|
}
|
|
if (*(blocks + EXT2_IND_BLOCK) || (flags & BLOCK_FLAG_APPEND)) {
|
|
ret |= block_iterate_ind(blocks + EXT2_IND_BLOCK, &ctx);
|
|
if (ret & BLOCK_ABORT)
|
|
goto abort;
|
|
}
|
|
if (*(blocks + EXT2_DIND_BLOCK) || (flags & BLOCK_FLAG_APPEND)) {
|
|
ret |= block_iterate_dind(blocks + EXT2_DIND_BLOCK, &ctx);
|
|
if (ret & BLOCK_ABORT)
|
|
goto abort;
|
|
}
|
|
if (*(blocks + EXT2_TIND_BLOCK) || (flags & BLOCK_FLAG_APPEND))
|
|
ret |= block_iterate_tind(blocks + EXT2_TIND_BLOCK, &ctx);
|
|
|
|
abort:
|
|
if (ret & BLOCK_CHANGED) {
|
|
retval = ext2fs_read_inode(fs, ino, &inode);
|
|
if (retval)
|
|
return retval;
|
|
for (i=0; i < EXT2_N_BLOCKS; i++)
|
|
inode.i_block[i] = blocks[i];
|
|
retval = ext2fs_write_inode(fs, ino, &inode);
|
|
if (retval)
|
|
return retval;
|
|
}
|
|
|
|
if (!block_buf)
|
|
free(ctx.ind_buf);
|
|
|
|
return (ret & BLOCK_ERROR) ? ctx.errcode : 0;
|
|
}
|