LXR busybox/e2fsprogs/old_e2fsprogs/ext2fs/expanddir.c

   1/* vi: set sw=4 ts=4: */
   2/*
   3 * expand.c --- expand an ext2fs directory
   4 *
   5 * Copyright (C) 1993, 1994, 1995, 1996, 1997, 1998, 1999  Theodore Ts'o.
   6 *
   7 * %Begin-Header%
   8 * This file may be redistributed under the terms of the GNU Public
   9 * License.
  10 * %End-Header%
  11 */
  12
  13#include <stdio.h>
  14#include <string.h>
  15#if HAVE_UNISTD_H
  16#include <unistd.h>
  17#endif
  18
  19#include "ext2_fs.h"
  20#include "ext2fs.h"
  21
  22struct expand_dir_struct {
  23        int             done;
  24        int             newblocks;
  25        errcode_t       err;
  26};
  27
  28static int expand_dir_proc(ext2_filsys  fs,
  29                           blk_t        *blocknr,
  30                           e2_blkcnt_t  blockcnt,
  31                           blk_t        ref_block EXT2FS_ATTR((unused)),
  32                           int          ref_offset EXT2FS_ATTR((unused)),
  33                           void         *priv_data)
  34{
  35        struct expand_dir_struct *es = (struct expand_dir_struct *) priv_data;
  36        blk_t   new_blk;
  37        static blk_t    last_blk = 0;
  38        char            *block;
  39        errcode_t       retval;
  40
  41        if (*blocknr) {
  42                last_blk = *blocknr;
  43                return 0;
  44        }
  45        retval = ext2fs_new_block(fs, last_blk, 0, &new_blk);
  46        if (retval) {
  47                es->err = retval;
  48                return BLOCK_ABORT;
  49        }
  50        if (blockcnt > 0) {
  51                retval = ext2fs_new_dir_block(fs, 0, 0, &block);
  52                if (retval) {
  53                        es->err = retval;
  54                        return BLOCK_ABORT;
  55                }
  56                es->done = 1;
  57                retval = ext2fs_write_dir_block(fs, new_blk, block);
  58        } else {
  59                retval = ext2fs_get_mem(fs->blocksize, &block);
  60                if (retval) {
  61                        es->err = retval;
  62                        return BLOCK_ABORT;
  63                }
  64                memset(block, 0, fs->blocksize);
  65                retval = io_channel_write_blk(fs->io, new_blk, 1, block);
  66        }
  67        if (retval) {
  68                es->err = retval;
  69                return BLOCK_ABORT;
  70        }
  71        ext2fs_free_mem(&block);
  72        *blocknr = new_blk;
  73        ext2fs_block_alloc_stats(fs, new_blk, +1);
  74        es->newblocks++;
  75
  76        if (es->done)
  77                return (BLOCK_CHANGED | BLOCK_ABORT);
  78        else
  79                return BLOCK_CHANGED;
  80}
  81
  82errcode_t ext2fs_expand_dir(ext2_filsys fs, ext2_ino_t dir)
  83{
  84        errcode_t       retval;
  85        struct expand_dir_struct es;
  86        struct ext2_inode       inode;
  87
  88        EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
  89
  90        if (!(fs->flags & EXT2_FLAG_RW))
  91                return EXT2_ET_RO_FILSYS;
  92
  93        if (!fs->block_map)
  94                return EXT2_ET_NO_BLOCK_BITMAP;
  95
  96        retval = ext2fs_check_directory(fs, dir);
  97        if (retval)
  98                return retval;
  99
 100        es.done = 0;
 101        es.err = 0;
 102        es.newblocks = 0;
 103
 104        retval = ext2fs_block_iterate2(fs, dir, BLOCK_FLAG_APPEND,
 105                                       0, expand_dir_proc, &es);
 106
 107        if (es.err)
 108                return es.err;
 109        if (!es.done)
 110                return EXT2_ET_EXPAND_DIR_ERR;
 111
 112        /*
 113         * Update the size and block count fields in the inode.
 114         */
 115        retval = ext2fs_read_inode(fs, dir, &inode);
 116        if (retval)
 117                return retval;
 118
 119        inode.i_size += fs->blocksize;
 120        inode.i_blocks += (fs->blocksize / 512) * es.newblocks;
 121
 122        retval = ext2fs_write_inode(fs, dir, &inode);
 123        if (retval)
 124                return retval;
 125
 126        return 0;
 127}
 128