1/*
2 * expand.c --- expand an ext2fs directory
3 *
4 * Copyright (C) 1993, 1994, 1995, 1996, 1997, 1998, 1999  Theodore Ts'o.
5 *
6 * %Begin-Header%
7 * This file may be redistributed under the terms of the GNU Library
8 * General Public License, version 2.
9 * %End-Header%
10 */
11
12#include <stdio.h>
13#include <string.h>
14#if HAVE_UNISTD_H
15#include <unistd.h>
16#endif
17
18#include "ext2_fs.h"
19#include "ext2fs.h"
20
21struct expand_dir_struct {
22	int		done;
23	int		newblocks;
24	blk64_t		goal;
25	errcode_t	err;
26};
27
28static int expand_dir_proc(ext2_filsys	fs,
29			   blk64_t	*blocknr,
30			   e2_blkcnt_t	blockcnt,
31			   blk64_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	blk64_t	new_blk;
37	char		*block;
38	errcode_t	retval;
39
40	if (*blocknr) {
41		if (blockcnt >= 0)
42			es->goal = *blocknr;
43		return 0;
44	}
45	if (blockcnt &&
46	    (EXT2FS_B2C(fs, es->goal) == EXT2FS_B2C(fs, es->goal+1)))
47		new_blk = es->goal+1;
48	else {
49		es->goal &= ~EXT2FS_CLUSTER_MASK(fs);
50		retval = ext2fs_new_block2(fs, es->goal, 0, &new_blk);
51		if (retval) {
52			es->err = retval;
53			return BLOCK_ABORT;
54		}
55		es->newblocks++;
56		ext2fs_block_alloc_stats2(fs, new_blk, +1);
57	}
58	if (blockcnt > 0) {
59		retval = ext2fs_new_dir_block(fs, 0, 0, &block);
60		if (retval) {
61			es->err = retval;
62			return BLOCK_ABORT;
63		}
64		es->done = 1;
65		retval = ext2fs_write_dir_block(fs, new_blk, block);
66	} else {
67		retval = ext2fs_get_mem(fs->blocksize, &block);
68		if (retval) {
69			es->err = retval;
70			return BLOCK_ABORT;
71		}
72		memset(block, 0, fs->blocksize);
73		retval = io_channel_write_blk64(fs->io, new_blk, 1, block);
74	}
75	if (blockcnt >= 0)
76		es->goal = new_blk;
77	if (retval) {
78		es->err = retval;
79		return BLOCK_ABORT;
80	}
81	ext2fs_free_mem(&block);
82	*blocknr = new_blk;
83
84	if (es->done)
85		return (BLOCK_CHANGED | BLOCK_ABORT);
86	else
87		return BLOCK_CHANGED;
88}
89
90errcode_t ext2fs_expand_dir(ext2_filsys fs, ext2_ino_t dir)
91{
92	errcode_t	retval;
93	struct expand_dir_struct es;
94	struct ext2_inode	inode;
95
96	EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
97
98	if (!(fs->flags & EXT2_FLAG_RW))
99		return EXT2_ET_RO_FILSYS;
100
101	if (!fs->block_map)
102		return EXT2_ET_NO_BLOCK_BITMAP;
103
104	retval = ext2fs_check_directory(fs, dir);
105	if (retval)
106		return retval;
107
108	es.done = 0;
109	es.err = 0;
110	es.goal = 0;
111	es.newblocks = 0;
112
113	retval = ext2fs_block_iterate3(fs, dir, BLOCK_FLAG_APPEND,
114				       0, expand_dir_proc, &es);
115
116	if (es.err)
117		return es.err;
118	if (!es.done)
119		return EXT2_ET_EXPAND_DIR_ERR;
120
121	/*
122	 * Update the size and block count fields in the inode.
123	 */
124	retval = ext2fs_read_inode(fs, dir, &inode);
125	if (retval)
126		return retval;
127
128	inode.i_size += fs->blocksize;
129	ext2fs_iblk_add_blocks(fs, &inode, es.newblocks);
130
131	retval = ext2fs_write_inode(fs, dir, &inode);
132	if (retval)
133		return retval;
134
135	return 0;
136}
137