text: /*
   * pass3.c -- pass #3 of e2fsck: Check for directory connectivity
   *
   * Copyright (C) 1993, 1994, 1995, 1996, 1997, 1998, 1999 Theodore Ts'o.
   *
   * %Begin-Header%
   * This file may be redistributed under the terms of the GNU Public
   * License.
   * %End-Header%
   * 
   * Pass #3 assures that all directories are connected to the
   * filesystem tree, using the following algorithm:
   *
   * First, the root directory is checked to make sure it exists; if
   * not, e2fsck will offer to create a new one.  It is then marked as
   * "done".
   * 
   * Then, pass3 interates over all directory inodes; for each directory
   * it attempts to trace up the filesystem tree, using dirinfo.parent
   * until it reaches a directory which has been marked "done".  If it
   * can not do so, then the directory must be disconnected, and e2fsck
   * will offer to reconnect it to /lost+found.  While it is chasing
   * parent pointers up the filesystem tree, if pass3 sees a directory
   * twice, then it has detected a filesystem loop, and it will again
   * offer to reconnect the directory to /lost+found in to break the
   * filesystem loop.
   * 
   * Pass 3 also contains the subroutine, e2fsck_reconnect_file() to
   * reconnect inodes to /lost+found; this subroutine is also used by
   * pass 4.  e2fsck_reconnect_file() calls get_lost_and_found(), which
   * is responsible for creating /lost+found if it does not exist.
   *
   * Pass 3 frees the following data structures:
   *     	- The dirinfo directory information cache.
   */
  
  #ifdef HAVE_ERRNO_H
  #include <errno.h>
  #endif
  
  #include "e2fsck.h"
  #include "problem.h"
  
  static void check_root(e2fsck_t ctx);
  static int check_directory(e2fsck_t ctx, struct dir_info *dir,
  			   struct problem_context *pctx);
  static void fix_dotdot(e2fsck_t ctx, struct dir_info *dir, ext2_ino_t parent);
  
  static ext2fs_inode_bitmap inode_loop_detect = 0;
  static ext2fs_inode_bitmap inode_done_map = 0;
  	
  void e2fsck_pass3(e2fsck_t ctx)
  {
  	ext2_filsys fs = ctx->fs;
  	int		i;
  #ifdef RESOURCE_TRACK
  	struct resource_track	rtrack;
  #endif
  	struct problem_context	pctx;
  	struct dir_info	*dir;
  	unsigned long maxdirs, count;
  
  #ifdef RESOURCE_TRACK
  	init_resource_track(&rtrack);
  #endif
  
  	clear_problem_context(&pctx);
  
  #ifdef MTRACE
  	mtrace_print("Pass 3");
  #endif
  
  	if (!(ctx->options & E2F_OPT_PREEN))
  		fix_problem(ctx, PR_3_PASS_HEADER, &pctx);
  
  	/*
  	 * Allocate some bitmaps to do loop detection.
  	 */
  	pctx.errcode = ext2fs_allocate_inode_bitmap(fs, _("inode done bitmap"),
  						    &inode_done_map);
  	if (pctx.errcode) {
  		pctx.num = 2;
  		fix_problem(ctx, PR_3_ALLOCATE_IBITMAP_ERROR, &pctx);
  		ctx->flags |= E2F_FLAG_ABORT;
  		goto abort_exit;
  	}
  #ifdef RESOURCE_TRACK
  	if (ctx->options & E2F_OPT_TIME) {
  		e2fsck_clear_progbar(ctx);
  		print_resource_track(_("Peak memory"), &ctx->global_rtrack);
  	}
  #endif
  
  	check_root(ctx);
  	if (ctx->flags & E2F_FLAG_SIGNAL_MASK)
  		goto abort_exit;
  
  	ext2fs_mark_inode_bitmap(inode_done_map, EXT2_ROOT_INO);
  
  	maxdirs = e2fsck_get_num_dirinfo(ctx);
  	count = 1;
  
  	if (ctx->progress)
  		if ((ctx->progress)(ctx, 3, 0, maxdirs))
  			goto abort_exit;
  	
  	for (i=0; (dir = e2fsck_dir_info_iter(ctx, &i)) != 0;) {
  		if (ctx->flags & E2F_FLAG_SIGNAL_MASK)
  			goto abort_exit;
  		if (ctx->progress && (ctx->progress)(ctx, 3, count++, maxdirs))
  			goto abort_exit;
  		if (ext2fs_test_inode_bitmap(ctx->inode_dir_map, dir->ino))
  			if (check_directory(ctx, dir, &pctx))
  				goto abort_exit;
  	}
  
  	/*
  	 * Force the creation of /lost+found if not present
  	 */
  	if ((ctx->flags & E2F_OPT_READONLY) == 0)
  		e2fsck_get_lost_and_found(ctx, 1);
  
  	/*
  	 * If there are any directories that need to be indexed or
  	 * optimized, do it here.
  	 */
  	e2fsck_rehash_directories(ctx);
  	
  abort_exit:
  	e2fsck_free_dir_info(ctx);
  	if (inode_loop_detect) {
  		ext2fs_free_inode_bitmap(inode_loop_detect);
  		inode_loop_detect = 0;
  	}
  	if (inode_done_map) {
  		ext2fs_free_inode_bitmap(inode_done_map);
  		inode_done_map = 0;
  	}
  
  #ifdef RESOURCE_TRACK
  	if (ctx->options & E2F_OPT_TIME2) {
  		e2fsck_clear_progbar(ctx);
  		print_resource_track(_("Pass 3"), &rtrack);
  	}
  #endif
  }
  
  /*
   * This makes sure the root inode is present; if not, we ask if the
   * user wants us to create it.  Not creating it is a fatal error.
   */
  static void check_root(e2fsck_t ctx)
  {
  	ext2_filsys fs = ctx->fs;
  	blk_t			blk;
  	struct ext2_inode	inode;
  	char *			block;
  	struct problem_context	pctx;
  	
  	clear_problem_context(&pctx);
  	
  	if (ext2fs_test_inode_bitmap(ctx->inode_used_map, EXT2_ROOT_INO)) {
  		/*
  		 * If the root inode is not a directory, die here.  The
  		 * user must have answered 'no' in pass1 when we
  		 * offered to clear it.
  		 */
  		if (!(ext2fs_test_inode_bitmap(ctx->inode_dir_map,
  					       EXT2_ROOT_INO))) {
  			fix_problem(ctx, PR_3_ROOT_NOT_DIR_ABORT, &pctx);
  			ctx->flags |= E2F_FLAG_ABORT;
  		}
  		return;
  	}
  
  	if (!fix_problem(ctx, PR_3_NO_ROOT_INODE, &pctx)) {
  		fix_problem(ctx, PR_3_NO_ROOT_INODE_ABORT, &pctx);
  		ctx->flags |= E2F_FLAG_ABORT;
  		return;
  	}
  
  	e2fsck_read_bitmaps(ctx);
  	
  	/*
  	 * First, find a free block
  	 */
  	pctx.errcode = ext2fs_new_block(fs, 0, ctx->block_found_map, &blk);
  	if (pctx.errcode) {
  		pctx.str = "ext2fs_new_block";
  		fix_problem(ctx, PR_3_CREATE_ROOT_ERROR, &pctx);
  		ctx->flags |= E2F_FLAG_ABORT;
  		return;
  	}
  	ext2fs_mark_block_bitmap(ctx->block_found_map, blk);
  	ext2fs_mark_block_bitmap(fs->block_map, blk);
  	ext2fs_mark_bb_dirty(fs);
  
  	/*
  	 * Now let's create the actual data block for the inode
  	 */
  	pctx.errcode = ext2fs_new_dir_block(fs, EXT2_ROOT_INO, EXT2_ROOT_INO,
  					    &block);
  	if (pctx.errcode) {
  		pctx.str = "ext2fs_new_dir_block";
  		fix_problem(ctx, PR_3_CREATE_ROOT_ERROR, &pctx);
  		ctx->flags |= E2F_FLAG_ABORT;
  		return;
  	}
  
  	pctx.errcode = ext2fs_write_dir_block(fs, blk, block);
  	if (pctx.errcode) {
  		pctx.str = "ext2fs_write_dir_block";
  		fix_problem(ctx, PR_3_CREATE_ROOT_ERROR, &pctx);
  		ctx->flags |= E2F_FLAG_ABORT;
  		return;
  	}
  	ext2fs_free_mem(&block);
  
  	/*
  	 * Set up the inode structure
  	 */
  	memset(&inode, 0, sizeof(inode));
  	inode.i_mode = 040755;
  	inode.i_size = fs->blocksize;
  	inode.i_atime = inode.i_ctime = inode.i_mtime = ctx->now;
  	inode.i_links_count = 2;
  	inode.i_blocks = fs->blocksize / 512;
  	inode.i_block[0] = blk;
  
  	/*
  	 * Write out the inode.
  	 */
  	pctx.errcode = ext2fs_write_new_inode(fs, EXT2_ROOT_INO, &inode);
  	if (pctx.errcode) {
  		pctx.str = "ext2fs_write_inode";
  		fix_problem(ctx, PR_3_CREATE_ROOT_ERROR, &pctx);
  		ctx->flags |= E2F_FLAG_ABORT;
  		return;
  	}
  	
  	/*
  	 * Miscellaneous bookkeeping...
  	 */
  	e2fsck_add_dir_info(ctx, EXT2_ROOT_INO, EXT2_ROOT_INO);
  	ext2fs_icount_store(ctx->inode_count, EXT2_ROOT_INO, 2);
  	ext2fs_icount_store(ctx->inode_link_info, EXT2_ROOT_INO, 2);
  
  	ext2fs_mark_inode_bitmap(ctx->inode_used_map, EXT2_ROOT_INO);
  	ext2fs_mark_inode_bitmap(ctx->inode_dir_map, EXT2_ROOT_INO);
  	ext2fs_mark_inode_bitmap(fs->inode_map, EXT2_ROOT_INO);
  	ext2fs_mark_ib_dirty(fs);
  }
  
  /*
   * This subroutine is responsible for making sure that a particular
   * directory is connected to the root; if it isn't we trace it up as
   * far as we can go, and then offer to connect the resulting parent to
   * the lost+found.  We have to do loop detection; if we ever discover
   * a loop, we treat that as a disconnected directory and offer to
   * reparent it to lost+found.
   * 
   * However, loop detection is expensive, because for very large
   * filesystems, the inode_loop_detect bitmap is huge, and clearing it
   * is non-trivial.  Loops in filesystems are also a rare error case,
   * and we shouldn't optimize for error cases.  So we try two passes of
   * the algorithm.  The first time, we ignore loop detection and merely
   * increment a counter; if the counter exceeds some extreme threshold,
   * then we try again with the loop detection bitmap enabled.
   */
  static int check_directory(e2fsck_t ctx, struct dir_info *dir,
  			   struct problem_context *pctx)
  {
  	ext2_filsys 	fs = ctx->fs;
  	struct dir_info *p = dir;
  	int		loop_pass = 0, parent_count = 0;
  
  	if (!p)
  		return 0;
  
  	while (1) {
  		/*
  		 * Mark this inode as being "done"; by the time we
  		 * return from this function, the inode we either be
  		 * verified as being connected to the directory tree,
  		 * or we will have offered to reconnect this to
  		 * lost+found.
  		 *
  		 * If it was marked done already, then we've reached a
  		 * parent we've already checked.
  		 */
  	  	if (ext2fs_mark_inode_bitmap(inode_done_map, p->ino))
  			break;
  
  		/*
  		 * If this directory doesn't have a parent, or we've
  		 * seen the parent once already, then offer to
  		 * reparent it to lost+found
  		 */
  		if (!p->parent ||
  		    (loop_pass && 
  		     (ext2fs_test_inode_bitmap(inode_loop_detect,
  					      p->parent)))) {
  			pctx->ino = p->ino;
  			if (fix_problem(ctx, PR_3_UNCONNECTED_DIR, pctx)) {
  				if (e2fsck_reconnect_file(ctx, pctx->ino))
  					ext2fs_unmark_valid(fs);
  				else {
  					p = e2fsck_get_dir_info(ctx, pctx->ino);
  					p->parent = ctx->lost_and_found;
  					fix_dotdot(ctx, p, ctx->lost_and_found);
  				}
  			}
  			break;
  		}
  		p = e2fsck_get_dir_info(ctx, p->parent);
  		if (!p) {
  			fix_problem(ctx, PR_3_NO_DIRINFO, pctx);
  			return 0;
  		}
  		if (loop_pass) {
  			ext2fs_mark_inode_bitmap(inode_loop_detect,
  						 p->ino);
  		} else if (parent_count++ > 2048) {
  			/*
  			 * If we've run into a path depth that's
  			 * greater than 2048, try again with the inode
  			 * loop bitmap turned on and start from the
  			 * top.
  			 */
  			loop_pass = 1;
  			if (inode_loop_detect)
  				ext2fs_clear_inode_bitmap(inode_loop_detect);
  			else {
  				pctx->errcode = ext2fs_allocate_inode_bitmap(fs, _("inode loop detection bitmap"), &inode_loop_detect);
  				if (pctx->errcode) {
  					pctx->num = 1;
  					fix_problem(ctx, 
  				    PR_3_ALLOCATE_IBITMAP_ERROR, pctx);
  					ctx->flags |= E2F_FLAG_ABORT;
  					return -1;
  				}
  			}
  			p = dir;
  		}
  	}
  
  	/*
  	 * Make sure that .. and the parent directory are the same;
  	 * offer to fix it if not.
  	 */
  	if (dir->parent != dir->dotdot) {
  		pctx->ino = dir->ino;
  		pctx->ino2 = dir->dotdot;
  		pctx->dir = dir->parent;
  		if (fix_problem(ctx, PR_3_BAD_DOT_DOT, pctx))
  			fix_dotdot(ctx, dir, dir->parent);
  	}
  	return 0;
  }
  
  /*
   * This routine gets the lost_and_found inode, making it a directory
   * if necessary
   */
  ext2_ino_t e2fsck_get_lost_and_found(e2fsck_t ctx, int fix)
  {
  	ext2_filsys fs = ctx->fs;
  	ext2_ino_t			ino;
  	blk_t			blk;
  	errcode_t		retval;
  	struct ext2_inode	inode;
  	char *			block;
  	static const char	name[] = "lost+found";
  	struct 	problem_context	pctx;
  	struct dir_info 	*dirinfo;
  
  	if (ctx->lost_and_found)
  		return ctx->lost_and_found;
  
  	clear_problem_context(&pctx);
  	
  	retval = ext2fs_lookup(fs, EXT2_ROOT_INO, name,
  			       sizeof(name)-1, 0, &ino);
  	if (retval && !fix)
  		return 0;
  	if (!retval) {
  		if (ext2fs_test_inode_bitmap(ctx->inode_dir_map, ino)) {
  			ctx->lost_and_found = ino;
  			return ino;
  		}
  				
  		/* Lost+found isn't a directory! */
  		if (!fix)
  			return 0;
  		pctx.ino = ino;
  		if (!fix_problem(ctx, PR_3_LPF_NOTDIR, &pctx))
  			return 0;
  
  		/* OK, unlink the old /lost+found file. */
  		pctx.errcode = ext2fs_unlink(fs, EXT2_ROOT_INO, name, ino, 0);
  		if (pctx.errcode) {
  			pctx.str = "ext2fs_unlink";
  			fix_problem(ctx, PR_3_CREATE_LPF_ERROR, &pctx);
  			return 0;
  		}
  		dirinfo = e2fsck_get_dir_info(ctx, ino);
  		if (dirinfo)
  			dirinfo->parent = 0;
  		e2fsck_adjust_inode_count(ctx, ino, -1);
  	} else if (retval != EXT2_ET_FILE_NOT_FOUND) {
  		pctx.errcode = retval;
  		fix_problem(ctx, PR_3_ERR_FIND_LPF, &pctx);
  	}
  	if (!fix_problem(ctx, PR_3_NO_LF_DIR, 0))
  		return 0;
  
  	/*
  	 * Read the inode and block bitmaps in; we'll be messing with
  	 * them.
  	 */
  	e2fsck_read_bitmaps(ctx);
  	
  	/*
  	 * First, find a free block
  	 */
  	retval = ext2fs_new_block(fs, 0, ctx->block_found_map, &blk);
  	if (retval) {
  		pctx.errcode = retval;
  		fix_problem(ctx, PR_3_ERR_LPF_NEW_BLOCK, &pctx);
  		return 0;
  	}
  	ext2fs_mark_block_bitmap(ctx->block_found_map, blk);
  	ext2fs_block_alloc_stats(fs, blk, +1);
  
  	/*
  	 * Next find a free inode.
  	 */
  	retval = ext2fs_new_inode(fs, EXT2_ROOT_INO, 040700,
  				  ctx->inode_used_map, &ino);
  	if (retval) {
  		pctx.errcode = retval;
  		fix_problem(ctx, PR_3_ERR_LPF_NEW_INODE, &pctx);
  		return 0;
  	}
  	ext2fs_mark_inode_bitmap(ctx->inode_used_map, ino);
  	ext2fs_mark_inode_bitmap(ctx->inode_dir_map, ino);
  	ext2fs_inode_alloc_stats2(fs, ino, +1, 1);
  
  	/*
  	 * Now let's create the actual data block for the inode
  	 */
  	retval = ext2fs_new_dir_block(fs, ino, EXT2_ROOT_INO, &block);
  	if (retval) {
  		pctx.errcode = retval;
  		fix_problem(ctx, PR_3_ERR_LPF_NEW_DIR_BLOCK, &pctx);
  		return 0;
  	}
  
  	retval = ext2fs_write_dir_block(fs, blk, block);
  	ext2fs_free_mem(&block);
  	if (retval) {
  		pctx.errcode = retval;
  		fix_problem(ctx, PR_3_ERR_LPF_WRITE_BLOCK, &pctx);
  		return 0;
  	}
  
  	/*
  	 * Set up the inode structure
  	 */
  	memset(&inode, 0, sizeof(inode));
  	inode.i_mode = 040700;
  	inode.i_size = fs->blocksize;
  	inode.i_atime = inode.i_ctime = inode.i_mtime = ctx->now;
  	inode.i_links_count = 2;
  	inode.i_blocks = fs->blocksize / 512;
  	inode.i_block[0] = blk;
  
  	/*
  	 * Next, write out the inode.
  	 */
  	pctx.errcode = ext2fs_write_new_inode(fs, ino, &inode);
  	if (pctx.errcode) {
  		pctx.str = "ext2fs_write_inode";
  		fix_problem(ctx, PR_3_CREATE_LPF_ERROR, &pctx);
  		return 0;
  	}
  	/*
  	 * Finally, create the directory link
  	 */
  	pctx.errcode = ext2fs_link(fs, EXT2_ROOT_INO, name, ino, EXT2_FT_DIR);
  	if (pctx.errcode) {
  		pctx.str = "ext2fs_link";
  		fix_problem(ctx, PR_3_CREATE_LPF_ERROR, &pctx);
  		return 0;
  	}
  
  	/*
  	 * Miscellaneous bookkeeping that needs to be kept straight.
  	 */
  	e2fsck_add_dir_info(ctx, ino, EXT2_ROOT_INO);
  	e2fsck_adjust_inode_count(ctx, EXT2_ROOT_INO, 1);
  	ext2fs_icount_store(ctx->inode_count, ino, 2);
  	ext2fs_icount_store(ctx->inode_link_info, ino, 2);
  	ctx->lost_and_found = ino;
  #if 0
  	printf("/lost+found created; inode #%lu\n", ino);
  #endif
  	return ino;
  }
  
  /*
   * This routine will connect a file to lost+found
   */
  int e2fsck_reconnect_file(e2fsck_t ctx, ext2_ino_t ino)
  {
  	ext2_filsys fs = ctx->fs;
  	errcode_t	retval;
  	char		name[80];
  	struct problem_context	pctx;
  	struct ext2_inode 	inode;
  	int		file_type = 0;
  
  	clear_problem_context(&pctx);
  	pctx.ino = ino;
  
  	if (!ctx->bad_lost_and_found && !ctx->lost_and_found) {
  		if (e2fsck_get_lost_and_found(ctx, 1) == 0)
  			ctx->bad_lost_and_found++;
  	}
  	if (ctx->bad_lost_and_found) {
  		fix_problem(ctx, PR_3_NO_LPF, &pctx);
  		return 1;
  	}
  	
  	sprintf(name, "#%u", ino);
  	if (ext2fs_read_inode(fs, ino, &inode) == 0)
  		file_type = ext2_file_type(inode.i_mode);
  	retval = ext2fs_link(fs, ctx->lost_and_found, name, ino, file_type);
  	if (retval == EXT2_ET_DIR_NO_SPACE) {
  		if (!fix_problem(ctx, PR_3_EXPAND_LF_DIR, &pctx))
  			return 1;
  		retval = e2fsck_expand_directory(ctx, ctx->lost_and_found, 
  						 1, 0);
  		if (retval) {
  			pctx.errcode = retval;
  			fix_problem(ctx, PR_3_CANT_EXPAND_LPF, &pctx);
  			return 1;
  		}
  		retval = ext2fs_link(fs, ctx->lost_and_found, name,
  				     ino, file_type);
  	}
  	if (retval) {
  		pctx.errcode = retval;
  		fix_problem(ctx, PR_3_CANT_RECONNECT, &pctx);
  		return 1;
  	}
  	e2fsck_adjust_inode_count(ctx, ino, 1);
  
  	return 0;
  }
  
  /*
   * Utility routine to adjust the inode counts on an inode.
   */
  errcode_t e2fsck_adjust_inode_count(e2fsck_t ctx, ext2_ino_t ino, int adj)
  {
  	ext2_filsys fs = ctx->fs;
  	errcode_t		retval;
  	struct ext2_inode 	inode;
  	
  	if (!ino)
  		return 0;
  
  	retval = ext2fs_read_inode(fs, ino, &inode);
  	if (retval)
  		return retval;
  
  #if 0
  	printf("Adjusting link count for inode %lu by %d (from %d)\n", ino, adj,
  	       inode.i_links_count);
  #endif
  
  	if (adj == 1) {
  		ext2fs_icount_increment(ctx->inode_count, ino, 0);
  		if (inode.i_links_count == (__u16) ~0)
  			return 0;
  		ext2fs_icount_increment(ctx->inode_link_info, ino, 0);
  		inode.i_links_count++;
  	} else if (adj == -1) {
  		ext2fs_icount_decrement(ctx->inode_count, ino, 0);
  		if (inode.i_links_count == 0)
  			return 0;
  		ext2fs_icount_decrement(ctx->inode_link_info, ino, 0);
  		inode.i_links_count--;
  	}
  	
  	retval = ext2fs_write_inode(fs, ino, &inode);
  	if (retval)
  		return retval;
  
  	return 0;
  }
  
  /*
   * Fix parent --- this routine fixes up the parent of a directory.
   */
  struct fix_dotdot_struct {
  	ext2_filsys	fs;
  	ext2_ino_t	parent;
  	int		done;
  	e2fsck_t	ctx;
  };
  
  static int fix_dotdot_proc(struct ext2_dir_entry *dirent,
  			   int	offset EXT2FS_ATTR((unused)),
  			   int	blocksize EXT2FS_ATTR((unused)),
  			   char	*buf EXT2FS_ATTR((unused)),
  			   void	*priv_data)
  {
  	struct fix_dotdot_struct *fp = (struct fix_dotdot_struct *) priv_data;
  	errcode_t	retval;
  	struct problem_context pctx;
  
  	if ((dirent->name_len & 0xFF) != 2)
  		return 0;
  	if (strncmp(dirent->name, "..", 2))
  		return 0;
  
  	clear_problem_context(&pctx);
  	
  	retval = e2fsck_adjust_inode_count(fp->ctx, dirent->inode, -1);
  	if (retval) {
  		pctx.errcode = retval;
  		fix_problem(fp->ctx, PR_3_ADJUST_INODE, &pctx);
  	}
  	retval = e2fsck_adjust_inode_count(fp->ctx, fp->parent, 1);
  	if (retval) {
  		pctx.errcode = retval;
  		fix_problem(fp->ctx, PR_3_ADJUST_INODE, &pctx);
  	}
  	dirent->inode = fp->parent;
  
  	fp->done++;
  	return DIRENT_ABORT | DIRENT_CHANGED;
  }
  
  static void fix_dotdot(e2fsck_t ctx, struct dir_info *dir, ext2_ino_t parent)
  {
  	ext2_filsys fs = ctx->fs;
  	errcode_t	retval;
  	struct fix_dotdot_struct fp;
  	struct problem_context pctx;
  
  	fp.fs = fs;
  	fp.parent = parent;
  	fp.done = 0;
  	fp.ctx = ctx;
  
  #if 0
  	printf("Fixing '..' of inode %lu to be %lu...\n", dir->ino, parent);
  #endif
  	
  	retval = ext2fs_dir_iterate(fs, dir->ino, DIRENT_FLAG_INCLUDE_EMPTY,
  				    0, fix_dotdot_proc, &fp);
  	if (retval || !fp.done) {
  		clear_problem_context(&pctx);
  		pctx.ino = dir->ino;
  		pctx.errcode = retval;
  		fix_problem(ctx, retval ? PR_3_FIX_PARENT_ERR :
  			    PR_3_FIX_PARENT_NOFIND, &pctx);
  		ext2fs_unmark_valid(fs);
  	}
  	dir->dotdot = parent;
  	
  	return;
  }
  
  /*
   * These routines are responsible for expanding a /lost+found if it is
   * too small.
   */
  
  struct expand_dir_struct {
  	int			num;
  	int			guaranteed_size;
  	int			newblocks;
  	int			last_block;
  	errcode_t		err;
  	e2fsck_t		ctx;
  };
  
  static int expand_dir_proc(ext2_filsys fs,
  			   blk_t	*blocknr,
  			   e2_blkcnt_t	blockcnt,
  			   blk_t ref_block EXT2FS_ATTR((unused)),
  			   int ref_offset EXT2FS_ATTR((unused)),
  			   void	*priv_data)
  {
  	struct expand_dir_struct *es = (struct expand_dir_struct *) priv_data;
  	blk_t	new_blk;
  	static blk_t	last_blk = 0;
  	char		*block;
  	errcode_t	retval;
  	e2fsck_t	ctx;
  
  	ctx = es->ctx;
  	
  	if (es->guaranteed_size && blockcnt >= es->guaranteed_size)
  		return BLOCK_ABORT;
  
  	if (blockcnt > 0)
  		es->last_block = blockcnt;
  	if (*blocknr) {
  		last_blk = *blocknr;
  		return 0;
  	}
  	retval = ext2fs_new_block(fs, last_blk, ctx->block_found_map,
  				  &new_blk);
  	if (retval) {
  		es->err = retval;
  		return BLOCK_ABORT;
  	}
  	if (blockcnt > 0) {
  		retval = ext2fs_new_dir_block(fs, 0, 0, &block);
  		if (retval) {
  			es->err = retval;
  			return BLOCK_ABORT;
  		}
  		es->num--;
  		retval = ext2fs_write_dir_block(fs, new_blk, block);
  	} else {
  		retval = ext2fs_get_mem(fs->blocksize, &block);
  		if (retval) {
  			es->err = retval;
  			return BLOCK_ABORT;
  		}
  		memset(block, 0, fs->blocksize);
  		retval = io_channel_write_blk(fs->io, new_blk, 1, block);
  	}	
  	if (retval) {
  		es->err = retval;
  		return BLOCK_ABORT;
  	}
  	ext2fs_free_mem(&block);
  	*blocknr = new_blk;
  	ext2fs_mark_block_bitmap(ctx->block_found_map, new_blk);
  	ext2fs_block_alloc_stats(fs, new_blk, +1);
  	es->newblocks++;
  	
  	if (es->num == 0)
  		return (BLOCK_CHANGED | BLOCK_ABORT);
  	else
  		return BLOCK_CHANGED;
  }
  
  errcode_t e2fsck_expand_directory(e2fsck_t ctx, ext2_ino_t dir,
  				  int num, int guaranteed_size)
  {
  	ext2_filsys fs = ctx->fs;
  	errcode_t	retval;
  	struct expand_dir_struct es;
  	struct ext2_inode	inode;
  	
  	if (!(fs->flags & EXT2_FLAG_RW))
  		return EXT2_ET_RO_FILSYS;
  
  	/*
  	 * Read the inode and block bitmaps in; we'll be messing with
  	 * them.
  	 */
  	e2fsck_read_bitmaps(ctx);
  
  	retval = ext2fs_check_directory(fs, dir);
  	if (retval)
  		return retval;
  	
  	es.num = num;
  	es.guaranteed_size = guaranteed_size;
  	es.last_block = 0;
  	es.err = 0;
  	es.newblocks = 0;
  	es.ctx = ctx;
  	
  	retval = ext2fs_block_iterate2(fs, dir, BLOCK_FLAG_APPEND,
  				       0, expand_dir_proc, &es);
  
  	if (es.err)
  		return es.err;
  
  	/*
  	 * Update the size and block count fields in the inode.
  	 */
  	retval = ext2fs_read_inode(fs, dir, &inode);
  	if (retval)
  		return retval;
  	
  	inode.i_size = (es.last_block + 1) * fs->blocksize;
  	inode.i_blocks += (fs->blocksize / 512) * es.newblocks;
  
  	e2fsck_write_inode(ctx, dir, &inode, "expand_directory");
  
  	return 0;
  }
  
  