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-rw-r--r--e2fsprogs/ext2fs/inode.c794
1 files changed, 794 insertions, 0 deletions
diff --git a/e2fsprogs/ext2fs/inode.c b/e2fsprogs/ext2fs/inode.c
new file mode 100644
index 0000000..222568e
--- /dev/null
+++ b/e2fsprogs/ext2fs/inode.c
@@ -0,0 +1,794 @@
+/*
+ * inode.c --- utility routines to read and write inodes
+ *
+ * Copyright (C) 1993, 1994, 1995, 1996, 1997 Theodore Ts'o.
+ *
+ * %Begin-Header%
+ * This file may be redistributed under the terms of the GNU Public
+ * License.
+ * %End-Header%
+ */
+
+#include <stdio.h>
+#include <string.h>
+#if HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+#if HAVE_ERRNO_H
+#include <errno.h>
+#endif
+#if HAVE_SYS_STAT_H
+#include <sys/stat.h>
+#endif
+#if HAVE_SYS_TYPES_H
+#include <sys/types.h>
+#endif
+
+#include "ext2_fs.h"
+#include "ext2fsP.h"
+#include "e2image.h"
+
+struct ext2_struct_inode_scan {
+ errcode_t magic;
+ ext2_filsys fs;
+ ext2_ino_t current_inode;
+ blk_t current_block;
+ dgrp_t current_group;
+ ext2_ino_t inodes_left;
+ blk_t blocks_left;
+ dgrp_t groups_left;
+ blk_t inode_buffer_blocks;
+ char * inode_buffer;
+ int inode_size;
+ char * ptr;
+ int bytes_left;
+ char *temp_buffer;
+ errcode_t (*done_group)(ext2_filsys fs,
+ ext2_inode_scan scan,
+ dgrp_t group,
+ void * priv_data);
+ void * done_group_data;
+ int bad_block_ptr;
+ int scan_flags;
+ int reserved[6];
+};
+
+/*
+ * This routine flushes the icache, if it exists.
+ */
+errcode_t ext2fs_flush_icache(ext2_filsys fs)
+{
+ int i;
+
+ if (!fs->icache)
+ return 0;
+
+ for (i=0; i < fs->icache->cache_size; i++)
+ fs->icache->cache[i].ino = 0;
+
+ fs->icache->buffer_blk = 0;
+ return 0;
+}
+
+static errcode_t create_icache(ext2_filsys fs)
+{
+ errcode_t retval;
+
+ if (fs->icache)
+ return 0;
+ retval = ext2fs_get_mem(sizeof(struct ext2_inode_cache), &fs->icache);
+ if (retval)
+ return retval;
+
+ memset(fs->icache, 0, sizeof(struct ext2_inode_cache));
+ retval = ext2fs_get_mem(fs->blocksize, &fs->icache->buffer);
+ if (retval) {
+ ext2fs_free_mem(&fs->icache);
+ return retval;
+ }
+ fs->icache->buffer_blk = 0;
+ fs->icache->cache_last = -1;
+ fs->icache->cache_size = 4;
+ fs->icache->refcount = 1;
+ retval = ext2fs_get_mem(sizeof(struct ext2_inode_cache_ent)
+ * fs->icache->cache_size,
+ &fs->icache->cache);
+ if (retval) {
+ ext2fs_free_mem(&fs->icache->buffer);
+ ext2fs_free_mem(&fs->icache);
+ return retval;
+ }
+ ext2fs_flush_icache(fs);
+ return 0;
+}
+
+errcode_t ext2fs_open_inode_scan(ext2_filsys fs, int buffer_blocks,
+ ext2_inode_scan *ret_scan)
+{
+ ext2_inode_scan scan;
+ errcode_t retval;
+ errcode_t (*save_get_blocks)(ext2_filsys f, ext2_ino_t ino, blk_t *blocks);
+
+ EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
+
+ /*
+ * If fs->badblocks isn't set, then set it --- since the inode
+ * scanning functions require it.
+ */
+ if (fs->badblocks == 0) {
+ /*
+ * Temporarly save fs->get_blocks and set it to zero,
+ * for compatibility with old e2fsck's.
+ */
+ save_get_blocks = fs->get_blocks;
+ fs->get_blocks = 0;
+ retval = ext2fs_read_bb_inode(fs, &fs->badblocks);
+ if (retval && fs->badblocks) {
+ ext2fs_badblocks_list_free(fs->badblocks);
+ fs->badblocks = 0;
+ }
+ fs->get_blocks = save_get_blocks;
+ }
+
+ retval = ext2fs_get_mem(sizeof(struct ext2_struct_inode_scan), &scan);
+ if (retval)
+ return retval;
+ memset(scan, 0, sizeof(struct ext2_struct_inode_scan));
+
+ scan->magic = EXT2_ET_MAGIC_INODE_SCAN;
+ scan->fs = fs;
+ scan->inode_size = EXT2_INODE_SIZE(fs->super);
+ scan->bytes_left = 0;
+ scan->current_group = 0;
+ scan->groups_left = fs->group_desc_count - 1;
+ scan->inode_buffer_blocks = buffer_blocks ? buffer_blocks : 8;
+ scan->current_block = scan->fs->
+ group_desc[scan->current_group].bg_inode_table;
+ scan->inodes_left = EXT2_INODES_PER_GROUP(scan->fs->super);
+ scan->blocks_left = scan->fs->inode_blocks_per_group;
+ retval = ext2fs_get_mem((size_t) (scan->inode_buffer_blocks *
+ fs->blocksize),
+ &scan->inode_buffer);
+ scan->done_group = 0;
+ scan->done_group_data = 0;
+ scan->bad_block_ptr = 0;
+ if (retval) {
+ ext2fs_free_mem(&scan);
+ return retval;
+ }
+ retval = ext2fs_get_mem(scan->inode_size, &scan->temp_buffer);
+ if (retval) {
+ ext2fs_free_mem(&scan->inode_buffer);
+ ext2fs_free_mem(&scan);
+ return retval;
+ }
+ if (scan->fs->badblocks && scan->fs->badblocks->num)
+ scan->scan_flags |= EXT2_SF_CHK_BADBLOCKS;
+ *ret_scan = scan;
+ return 0;
+}
+
+void ext2fs_close_inode_scan(ext2_inode_scan scan)
+{
+ if (!scan || (scan->magic != EXT2_ET_MAGIC_INODE_SCAN))
+ return;
+
+ ext2fs_free_mem(&scan->inode_buffer);
+ scan->inode_buffer = NULL;
+ ext2fs_free_mem(&scan->temp_buffer);
+ scan->temp_buffer = NULL;
+ ext2fs_free_mem(&scan);
+ return;
+}
+
+void ext2fs_set_inode_callback(ext2_inode_scan scan,
+ errcode_t (*done_group)(ext2_filsys fs,
+ ext2_inode_scan scan,
+ dgrp_t group,
+ void * priv_data),
+ void *done_group_data)
+{
+ if (!scan || (scan->magic != EXT2_ET_MAGIC_INODE_SCAN))
+ return;
+
+ scan->done_group = done_group;
+ scan->done_group_data = done_group_data;
+}
+
+int ext2fs_inode_scan_flags(ext2_inode_scan scan, int set_flags,
+ int clear_flags)
+{
+ int old_flags;
+
+ if (!scan || (scan->magic != EXT2_ET_MAGIC_INODE_SCAN))
+ return 0;
+
+ old_flags = scan->scan_flags;
+ scan->scan_flags &= ~clear_flags;
+ scan->scan_flags |= set_flags;
+ return old_flags;
+}
+
+/*
+ * This function is called by ext2fs_get_next_inode when it needs to
+ * get ready to read in a new blockgroup.
+ */
+static errcode_t get_next_blockgroup(ext2_inode_scan scan)
+{
+ scan->current_group++;
+ scan->groups_left--;
+
+ scan->current_block = scan->fs->
+ group_desc[scan->current_group].bg_inode_table;
+
+ scan->current_inode = scan->current_group *
+ EXT2_INODES_PER_GROUP(scan->fs->super);
+
+ scan->bytes_left = 0;
+ scan->inodes_left = EXT2_INODES_PER_GROUP(scan->fs->super);
+ scan->blocks_left = scan->fs->inode_blocks_per_group;
+ return 0;
+}
+
+errcode_t ext2fs_inode_scan_goto_blockgroup(ext2_inode_scan scan,
+ int group)
+{
+ scan->current_group = group - 1;
+ scan->groups_left = scan->fs->group_desc_count - group;
+ return get_next_blockgroup(scan);
+}
+
+/*
+ * This function is called by get_next_blocks() to check for bad
+ * blocks in the inode table.
+ *
+ * This function assumes that badblocks_list->list is sorted in
+ * increasing order.
+ */
+static errcode_t check_for_inode_bad_blocks(ext2_inode_scan scan,
+ blk_t *num_blocks)
+{
+ blk_t blk = scan->current_block;
+ badblocks_list bb = scan->fs->badblocks;
+
+ /*
+ * If the inode table is missing, then obviously there are no
+ * bad blocks. :-)
+ */
+ if (blk == 0)
+ return 0;
+
+ /*
+ * If the current block is greater than the bad block listed
+ * in the bad block list, then advance the pointer until this
+ * is no longer the case. If we run out of bad blocks, then
+ * we don't need to do any more checking!
+ */
+ while (blk > bb->list[scan->bad_block_ptr]) {
+ if (++scan->bad_block_ptr >= bb->num) {
+ scan->scan_flags &= ~EXT2_SF_CHK_BADBLOCKS;
+ return 0;
+ }
+ }
+
+ /*
+ * If the current block is equal to the bad block listed in
+ * the bad block list, then handle that one block specially.
+ * (We could try to handle runs of bad blocks, but that
+ * only increases CPU efficiency by a small amount, at the
+ * expense of a huge expense of code complexity, and for an
+ * uncommon case at that.)
+ */
+ if (blk == bb->list[scan->bad_block_ptr]) {
+ scan->scan_flags |= EXT2_SF_BAD_INODE_BLK;
+ *num_blocks = 1;
+ if (++scan->bad_block_ptr >= bb->num)
+ scan->scan_flags &= ~EXT2_SF_CHK_BADBLOCKS;
+ return 0;
+ }
+
+ /*
+ * If there is a bad block in the range that we're about to
+ * read in, adjust the number of blocks to read so that we we
+ * don't read in the bad block. (Then the next block to read
+ * will be the bad block, which is handled in the above case.)
+ */
+ if ((blk + *num_blocks) > bb->list[scan->bad_block_ptr])
+ *num_blocks = (int) (bb->list[scan->bad_block_ptr] - blk);
+
+ return 0;
+}
+
+/*
+ * This function is called by ext2fs_get_next_inode when it needs to
+ * read in more blocks from the current blockgroup's inode table.
+ */
+static errcode_t get_next_blocks(ext2_inode_scan scan)
+{
+ blk_t num_blocks;
+ errcode_t retval;
+
+ /*
+ * Figure out how many blocks to read; we read at most
+ * inode_buffer_blocks, and perhaps less if there aren't that
+ * many blocks left to read.
+ */
+ num_blocks = scan->inode_buffer_blocks;
+ if (num_blocks > scan->blocks_left)
+ num_blocks = scan->blocks_left;
+
+ /*
+ * If the past block "read" was a bad block, then mark the
+ * left-over extra bytes as also being bad.
+ */
+ if (scan->scan_flags & EXT2_SF_BAD_INODE_BLK) {
+ if (scan->bytes_left)
+ scan->scan_flags |= EXT2_SF_BAD_EXTRA_BYTES;
+ scan->scan_flags &= ~EXT2_SF_BAD_INODE_BLK;
+ }
+
+ /*
+ * Do inode bad block processing, if necessary.
+ */
+ if (scan->scan_flags & EXT2_SF_CHK_BADBLOCKS) {
+ retval = check_for_inode_bad_blocks(scan, &num_blocks);
+ if (retval)
+ return retval;
+ }
+
+ if ((scan->scan_flags & EXT2_SF_BAD_INODE_BLK) ||
+ (scan->current_block == 0)) {
+ memset(scan->inode_buffer, 0,
+ (size_t) num_blocks * scan->fs->blocksize);
+ } else {
+ retval = io_channel_read_blk(scan->fs->io,
+ scan->current_block,
+ (int) num_blocks,
+ scan->inode_buffer);
+ if (retval)
+ return EXT2_ET_NEXT_INODE_READ;
+ }
+ scan->ptr = scan->inode_buffer;
+ scan->bytes_left = num_blocks * scan->fs->blocksize;
+
+ scan->blocks_left -= num_blocks;
+ if (scan->current_block)
+ scan->current_block += num_blocks;
+ return 0;
+}
+
+#if 0
+/*
+ * Returns 1 if the entire inode_buffer has a non-zero size and
+ * contains all zeros. (Not just deleted inodes, since that means
+ * that part of the inode table was used at one point; we want all
+ * zeros, which means that the inode table is pristine.)
+ */
+static inline int is_empty_scan(ext2_inode_scan scan)
+{
+ int i;
+
+ if (scan->bytes_left == 0)
+ return 0;
+
+ for (i=0; i < scan->bytes_left; i++)
+ if (scan->ptr[i])
+ return 0;
+ return 1;
+}
+#endif
+
+errcode_t ext2fs_get_next_inode_full(ext2_inode_scan scan, ext2_ino_t *ino,
+ struct ext2_inode *inode, int bufsize)
+{
+ errcode_t retval;
+ int extra_bytes = 0;
+
+ EXT2_CHECK_MAGIC(scan, EXT2_ET_MAGIC_INODE_SCAN);
+
+ /*
+ * Do we need to start reading a new block group?
+ */
+ if (scan->inodes_left <= 0) {
+ force_new_group:
+ if (scan->done_group) {
+ retval = (scan->done_group)
+ (scan->fs, scan, scan->current_group,
+ scan->done_group_data);
+ if (retval)
+ return retval;
+ }
+ if (scan->groups_left <= 0) {
+ *ino = 0;
+ return 0;
+ }
+ retval = get_next_blockgroup(scan);
+ if (retval)
+ return retval;
+ }
+ /*
+ * This is done outside the above if statement so that the
+ * check can be done for block group #0.
+ */
+ if (scan->current_block == 0) {
+ if (scan->scan_flags & EXT2_SF_SKIP_MISSING_ITABLE) {
+ goto force_new_group;
+ } else
+ return EXT2_ET_MISSING_INODE_TABLE;
+ }
+
+
+ /*
+ * Have we run out of space in the inode buffer? If so, we
+ * need to read in more blocks.
+ */
+ if (scan->bytes_left < scan->inode_size) {
+ memcpy(scan->temp_buffer, scan->ptr, scan->bytes_left);
+ extra_bytes = scan->bytes_left;
+
+ retval = get_next_blocks(scan);
+ if (retval)
+ return retval;
+#if 0
+ /*
+ * XXX test Need check for used inode somehow.
+ * (Note: this is hard.)
+ */
+ if (is_empty_scan(scan))
+ goto force_new_group;
+#endif
+ }
+
+ retval = 0;
+ if (extra_bytes) {
+ memcpy(scan->temp_buffer+extra_bytes, scan->ptr,
+ scan->inode_size - extra_bytes);
+ scan->ptr += scan->inode_size - extra_bytes;
+ scan->bytes_left -= scan->inode_size - extra_bytes;
+
+#ifdef EXT2FS_ENABLE_SWAPFS
+ if ((scan->fs->flags & EXT2_FLAG_SWAP_BYTES) ||
+ (scan->fs->flags & EXT2_FLAG_SWAP_BYTES_READ))
+ ext2fs_swap_inode_full(scan->fs,
+ (struct ext2_inode_large *) inode,
+ (struct ext2_inode_large *) scan->temp_buffer,
+ 0, bufsize);
+ else
+#endif
+ *inode = *((struct ext2_inode *) scan->temp_buffer);
+ if (scan->scan_flags & EXT2_SF_BAD_EXTRA_BYTES)
+ retval = EXT2_ET_BAD_BLOCK_IN_INODE_TABLE;
+ scan->scan_flags &= ~EXT2_SF_BAD_EXTRA_BYTES;
+ } else {
+#ifdef EXT2FS_ENABLE_SWAPFS
+ if ((scan->fs->flags & EXT2_FLAG_SWAP_BYTES) ||
+ (scan->fs->flags & EXT2_FLAG_SWAP_BYTES_READ))
+ ext2fs_swap_inode_full(scan->fs,
+ (struct ext2_inode_large *) inode,
+ (struct ext2_inode_large *) scan->ptr,
+ 0, bufsize);
+ else
+#endif
+ memcpy(inode, scan->ptr, bufsize);
+ scan->ptr += scan->inode_size;
+ scan->bytes_left -= scan->inode_size;
+ if (scan->scan_flags & EXT2_SF_BAD_INODE_BLK)
+ retval = EXT2_ET_BAD_BLOCK_IN_INODE_TABLE;
+ }
+
+ scan->inodes_left--;
+ scan->current_inode++;
+ *ino = scan->current_inode;
+ return retval;
+}
+
+errcode_t ext2fs_get_next_inode(ext2_inode_scan scan, ext2_ino_t *ino,
+ struct ext2_inode *inode)
+{
+ return ext2fs_get_next_inode_full(scan, ino, inode,
+ sizeof(struct ext2_inode));
+}
+
+/*
+ * Functions to read and write a single inode.
+ */
+errcode_t ext2fs_read_inode_full(ext2_filsys fs, ext2_ino_t ino,
+ struct ext2_inode * inode, int bufsize)
+{
+ unsigned long group, block, block_nr, offset;
+ char *ptr;
+ errcode_t retval;
+ int clen, i, inodes_per_block, length;
+ io_channel io;
+
+ EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
+
+ /* Check to see if user has an override function */
+ if (fs->read_inode) {
+ retval = (fs->read_inode)(fs, ino, inode);
+ if (retval != EXT2_ET_CALLBACK_NOTHANDLED)
+ return retval;
+ }
+ /* Create inode cache if not present */
+ if (!fs->icache) {
+ retval = create_icache(fs);
+ if (retval)
+ return retval;
+ }
+ /* Check to see if it's in the inode cache */
+ if (bufsize == sizeof(struct ext2_inode)) {
+ /* only old good inode can be retrieve from the cache */
+ for (i=0; i < fs->icache->cache_size; i++) {
+ if (fs->icache->cache[i].ino == ino) {
+ *inode = fs->icache->cache[i].inode;
+ return 0;
+ }
+ }
+ }
+ if ((ino == 0) || (ino > fs->super->s_inodes_count))
+ return EXT2_ET_BAD_INODE_NUM;
+ if (fs->flags & EXT2_FLAG_IMAGE_FILE) {
+ inodes_per_block = fs->blocksize / EXT2_INODE_SIZE(fs->super);
+ block_nr = fs->image_header->offset_inode / fs->blocksize;
+ block_nr += (ino - 1) / inodes_per_block;
+ offset = ((ino - 1) % inodes_per_block) *
+ EXT2_INODE_SIZE(fs->super);
+ io = fs->image_io;
+ } else {
+ group = (ino - 1) / EXT2_INODES_PER_GROUP(fs->super);
+ offset = ((ino - 1) % EXT2_INODES_PER_GROUP(fs->super)) *
+ EXT2_INODE_SIZE(fs->super);
+ block = offset >> EXT2_BLOCK_SIZE_BITS(fs->super);
+ if (!fs->group_desc[(unsigned)group].bg_inode_table)
+ return EXT2_ET_MISSING_INODE_TABLE;
+ block_nr = fs->group_desc[(unsigned)group].bg_inode_table +
+ block;
+ io = fs->io;
+ }
+ offset &= (EXT2_BLOCK_SIZE(fs->super) - 1);
+
+ length = EXT2_INODE_SIZE(fs->super);
+ if (bufsize < length)
+ length = bufsize;
+
+ ptr = (char *) inode;
+ while (length) {
+ clen = length;
+ if ((offset + length) > fs->blocksize)
+ clen = fs->blocksize - offset;
+
+ if (block_nr != fs->icache->buffer_blk) {
+ retval = io_channel_read_blk(io, block_nr, 1,
+ fs->icache->buffer);
+ if (retval)
+ return retval;
+ fs->icache->buffer_blk = block_nr;
+ }
+
+ memcpy(ptr, ((char *) fs->icache->buffer) + (unsigned) offset,
+ clen);
+
+ offset = 0;
+ length -= clen;
+ ptr += clen;
+ block_nr++;
+ }
+
+#ifdef EXT2FS_ENABLE_SWAPFS
+ if ((fs->flags & EXT2_FLAG_SWAP_BYTES) ||
+ (fs->flags & EXT2_FLAG_SWAP_BYTES_READ))
+ ext2fs_swap_inode_full(fs, (struct ext2_inode_large *) inode,
+ (struct ext2_inode_large *) inode,
+ 0, length);
+#endif
+
+ /* Update the inode cache */
+ fs->icache->cache_last = (fs->icache->cache_last + 1) %
+ fs->icache->cache_size;
+ fs->icache->cache[fs->icache->cache_last].ino = ino;
+ fs->icache->cache[fs->icache->cache_last].inode = *inode;
+
+ return 0;
+}
+
+errcode_t ext2fs_read_inode(ext2_filsys fs, ext2_ino_t ino,
+ struct ext2_inode * inode)
+{
+ return ext2fs_read_inode_full(fs, ino, inode,
+ sizeof(struct ext2_inode));
+}
+
+errcode_t ext2fs_write_inode_full(ext2_filsys fs, ext2_ino_t ino,
+ struct ext2_inode * inode, int bufsize)
+{
+ unsigned long group, block, block_nr, offset;
+ errcode_t retval = 0;
+ struct ext2_inode_large temp_inode, *w_inode;
+ char *ptr;
+ int clen, i, length;
+
+ EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
+
+ /* Check to see if user provided an override function */
+ if (fs->write_inode) {
+ retval = (fs->write_inode)(fs, ino, inode);
+ if (retval != EXT2_ET_CALLBACK_NOTHANDLED)
+ return retval;
+ }
+
+ /* Check to see if the inode cache needs to be updated */
+ if (fs->icache) {
+ for (i=0; i < fs->icache->cache_size; i++) {
+ if (fs->icache->cache[i].ino == ino) {
+ fs->icache->cache[i].inode = *inode;
+ break;
+ }
+ }
+ } else {
+ retval = create_icache(fs);
+ if (retval)
+ return retval;
+ }
+
+ if (!(fs->flags & EXT2_FLAG_RW))
+ return EXT2_ET_RO_FILSYS;
+
+ if ((ino == 0) || (ino > fs->super->s_inodes_count))
+ return EXT2_ET_BAD_INODE_NUM;
+
+ length = bufsize;
+ if (length < EXT2_INODE_SIZE(fs->super))
+ length = EXT2_INODE_SIZE(fs->super);
+
+ if (length > (int) sizeof(struct ext2_inode_large)) {
+ w_inode = malloc(length);
+ if (!w_inode)
+ return ENOMEM;
+ } else
+ w_inode = &temp_inode;
+ memset(w_inode, 0, length);
+
+#ifdef EXT2FS_ENABLE_SWAPFS
+ if ((fs->flags & EXT2_FLAG_SWAP_BYTES) ||
+ (fs->flags & EXT2_FLAG_SWAP_BYTES_WRITE))
+ ext2fs_swap_inode_full(fs, w_inode,
+ (struct ext2_inode_large *) inode,
+ 1, bufsize);
+ else
+#endif
+ memcpy(w_inode, inode, bufsize);
+
+ group = (ino - 1) / EXT2_INODES_PER_GROUP(fs->super);
+ offset = ((ino - 1) % EXT2_INODES_PER_GROUP(fs->super)) *
+ EXT2_INODE_SIZE(fs->super);
+ block = offset >> EXT2_BLOCK_SIZE_BITS(fs->super);
+ if (!fs->group_desc[(unsigned) group].bg_inode_table)
+ return EXT2_ET_MISSING_INODE_TABLE;
+ block_nr = fs->group_desc[(unsigned) group].bg_inode_table + block;
+
+ offset &= (EXT2_BLOCK_SIZE(fs->super) - 1);
+
+ length = EXT2_INODE_SIZE(fs->super);
+ if (length > bufsize)
+ length = bufsize;
+
+ ptr = (char *) w_inode;
+
+ while (length) {
+ clen = length;
+ if ((offset + length) > fs->blocksize)
+ clen = fs->blocksize - offset;
+
+ if (fs->icache->buffer_blk != block_nr) {
+ retval = io_channel_read_blk(fs->io, block_nr, 1,
+ fs->icache->buffer);
+ if (retval)
+ goto errout;
+ fs->icache->buffer_blk = block_nr;
+ }
+
+
+ memcpy((char *) fs->icache->buffer + (unsigned) offset,
+ ptr, clen);
+
+ retval = io_channel_write_blk(fs->io, block_nr, 1,
+ fs->icache->buffer);
+ if (retval)
+ goto errout;
+
+ offset = 0;
+ ptr += clen;
+ length -= clen;
+ block_nr++;
+ }
+
+ fs->flags |= EXT2_FLAG_CHANGED;
+errout:
+ if (w_inode && w_inode != &temp_inode)
+ free(w_inode);
+ return retval;
+}
+
+errcode_t ext2fs_write_inode(ext2_filsys fs, ext2_ino_t ino,
+ struct ext2_inode *inode)
+{
+ return ext2fs_write_inode_full(fs, ino, inode,
+ sizeof(struct ext2_inode));
+}
+
+/*
+ * This function should be called when writing a new inode. It makes
+ * sure that extra part of large inodes is initialized properly.
+ */
+errcode_t ext2fs_write_new_inode(ext2_filsys fs, ext2_ino_t ino,
+ struct ext2_inode *inode)
+{
+ struct ext2_inode *buf;
+ int size = EXT2_INODE_SIZE(fs->super);
+ struct ext2_inode_large *large_inode;
+
+ if (size == sizeof(struct ext2_inode))
+ return ext2fs_write_inode_full(fs, ino, inode,
+ sizeof(struct ext2_inode));
+
+ buf = malloc(size);
+ if (!buf)
+ return ENOMEM;
+
+ memset(buf, 0, size);
+ *buf = *inode;
+
+ large_inode = (struct ext2_inode_large *) buf;
+ large_inode->i_extra_isize = sizeof(struct ext2_inode_large) -
+ EXT2_GOOD_OLD_INODE_SIZE;
+
+ return ext2fs_write_inode_full(fs, ino, buf, size);
+}
+
+
+errcode_t ext2fs_get_blocks(ext2_filsys fs, ext2_ino_t ino, blk_t *blocks)
+{
+ struct ext2_inode inode;
+ int i;
+ errcode_t retval;
+
+ EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
+
+ if (ino > fs->super->s_inodes_count)
+ return EXT2_ET_BAD_INODE_NUM;
+
+ if (fs->get_blocks) {
+ if (!(*fs->get_blocks)(fs, ino, blocks))
+ return 0;
+ }
+ retval = ext2fs_read_inode(fs, ino, &inode);
+ if (retval)
+ return retval;
+ for (i=0; i < EXT2_N_BLOCKS; i++)
+ blocks[i] = inode.i_block[i];
+ return 0;
+}
+
+errcode_t ext2fs_check_directory(ext2_filsys fs, ext2_ino_t ino)
+{
+ struct ext2_inode inode;
+ errcode_t retval;
+
+ EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
+
+ if (ino > fs->super->s_inodes_count)
+ return EXT2_ET_BAD_INODE_NUM;
+
+ if (fs->check_directory) {
+ retval = (fs->check_directory)(fs, ino);
+ if (retval != EXT2_ET_CALLBACK_NOTHANDLED)
+ return retval;
+ }
+ retval = ext2fs_read_inode(fs, ino, &inode);
+ if (retval)
+ return retval;
+ if (!LINUX_S_ISDIR(inode.i_mode))
+ return EXT2_ET_NO_DIRECTORY;
+ return 0;
+}
+