release/src/router/busybox/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
  22 struct expand_dir_struct {
  23         int             done;
  24         int             newblocks;
  25         errcode_t       err;
  26 };
  27
  28 static 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
  82 errcode_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 }