xref: /linux/fs/hfs/dir.c (revision e190bfe56841551b1ad5abb42ebd0c4798cc8c01)
1 /*
2  *  linux/fs/hfs/dir.c
3  *
4  * Copyright (C) 1995-1997  Paul H. Hargrove
5  * (C) 2003 Ardis Technologies <roman@ardistech.com>
6  * This file may be distributed under the terms of the GNU General Public License.
7  *
8  * This file contains directory-related functions independent of which
9  * scheme is being used to represent forks.
10  *
11  * Based on the minix file system code, (C) 1991, 1992 by Linus Torvalds
12  */
13 
14 #include "hfs_fs.h"
15 #include "btree.h"
16 
17 /*
18  * hfs_lookup()
19  */
20 static struct dentry *hfs_lookup(struct inode *dir, struct dentry *dentry,
21 				 struct nameidata *nd)
22 {
23 	hfs_cat_rec rec;
24 	struct hfs_find_data fd;
25 	struct inode *inode = NULL;
26 	int res;
27 
28 	dentry->d_op = &hfs_dentry_operations;
29 
30 	hfs_find_init(HFS_SB(dir->i_sb)->cat_tree, &fd);
31 	hfs_cat_build_key(dir->i_sb, fd.search_key, dir->i_ino, &dentry->d_name);
32 	res = hfs_brec_read(&fd, &rec, sizeof(rec));
33 	if (res) {
34 		hfs_find_exit(&fd);
35 		if (res == -ENOENT) {
36 			/* No such entry */
37 			inode = NULL;
38 			goto done;
39 		}
40 		return ERR_PTR(res);
41 	}
42 	inode = hfs_iget(dir->i_sb, &fd.search_key->cat, &rec);
43 	hfs_find_exit(&fd);
44 	if (!inode)
45 		return ERR_PTR(-EACCES);
46 done:
47 	d_add(dentry, inode);
48 	return NULL;
49 }
50 
51 /*
52  * hfs_readdir
53  */
54 static int hfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
55 {
56 	struct inode *inode = filp->f_path.dentry->d_inode;
57 	struct super_block *sb = inode->i_sb;
58 	int len, err;
59 	char strbuf[HFS_MAX_NAMELEN];
60 	union hfs_cat_rec entry;
61 	struct hfs_find_data fd;
62 	struct hfs_readdir_data *rd;
63 	u16 type;
64 
65 	if (filp->f_pos >= inode->i_size)
66 		return 0;
67 
68 	hfs_find_init(HFS_SB(sb)->cat_tree, &fd);
69 	hfs_cat_build_key(sb, fd.search_key, inode->i_ino, NULL);
70 	err = hfs_brec_find(&fd);
71 	if (err)
72 		goto out;
73 
74 	switch ((u32)filp->f_pos) {
75 	case 0:
76 		/* This is completely artificial... */
77 		if (filldir(dirent, ".", 1, 0, inode->i_ino, DT_DIR))
78 			goto out;
79 		filp->f_pos++;
80 		/* fall through */
81 	case 1:
82 		if (fd.entrylength > sizeof(entry) || fd.entrylength < 0) {
83 			err = -EIO;
84 			goto out;
85 		}
86 
87 		hfs_bnode_read(fd.bnode, &entry, fd.entryoffset, fd.entrylength);
88 		if (entry.type != HFS_CDR_THD) {
89 			printk(KERN_ERR "hfs: bad catalog folder thread\n");
90 			err = -EIO;
91 			goto out;
92 		}
93 		//if (fd.entrylength < HFS_MIN_THREAD_SZ) {
94 		//	printk(KERN_ERR "hfs: truncated catalog thread\n");
95 		//	err = -EIO;
96 		//	goto out;
97 		//}
98 		if (filldir(dirent, "..", 2, 1,
99 			    be32_to_cpu(entry.thread.ParID), DT_DIR))
100 			goto out;
101 		filp->f_pos++;
102 		/* fall through */
103 	default:
104 		if (filp->f_pos >= inode->i_size)
105 			goto out;
106 		err = hfs_brec_goto(&fd, filp->f_pos - 1);
107 		if (err)
108 			goto out;
109 	}
110 
111 	for (;;) {
112 		if (be32_to_cpu(fd.key->cat.ParID) != inode->i_ino) {
113 			printk(KERN_ERR "hfs: walked past end of dir\n");
114 			err = -EIO;
115 			goto out;
116 		}
117 
118 		if (fd.entrylength > sizeof(entry) || fd.entrylength < 0) {
119 			err = -EIO;
120 			goto out;
121 		}
122 
123 		hfs_bnode_read(fd.bnode, &entry, fd.entryoffset, fd.entrylength);
124 		type = entry.type;
125 		len = hfs_mac2asc(sb, strbuf, &fd.key->cat.CName);
126 		if (type == HFS_CDR_DIR) {
127 			if (fd.entrylength < sizeof(struct hfs_cat_dir)) {
128 				printk(KERN_ERR "hfs: small dir entry\n");
129 				err = -EIO;
130 				goto out;
131 			}
132 			if (filldir(dirent, strbuf, len, filp->f_pos,
133 				    be32_to_cpu(entry.dir.DirID), DT_DIR))
134 				break;
135 		} else if (type == HFS_CDR_FIL) {
136 			if (fd.entrylength < sizeof(struct hfs_cat_file)) {
137 				printk(KERN_ERR "hfs: small file entry\n");
138 				err = -EIO;
139 				goto out;
140 			}
141 			if (filldir(dirent, strbuf, len, filp->f_pos,
142 				    be32_to_cpu(entry.file.FlNum), DT_REG))
143 				break;
144 		} else {
145 			printk(KERN_ERR "hfs: bad catalog entry type %d\n", type);
146 			err = -EIO;
147 			goto out;
148 		}
149 		filp->f_pos++;
150 		if (filp->f_pos >= inode->i_size)
151 			goto out;
152 		err = hfs_brec_goto(&fd, 1);
153 		if (err)
154 			goto out;
155 	}
156 	rd = filp->private_data;
157 	if (!rd) {
158 		rd = kmalloc(sizeof(struct hfs_readdir_data), GFP_KERNEL);
159 		if (!rd) {
160 			err = -ENOMEM;
161 			goto out;
162 		}
163 		filp->private_data = rd;
164 		rd->file = filp;
165 		list_add(&rd->list, &HFS_I(inode)->open_dir_list);
166 	}
167 	memcpy(&rd->key, &fd.key, sizeof(struct hfs_cat_key));
168 out:
169 	hfs_find_exit(&fd);
170 	return err;
171 }
172 
173 static int hfs_dir_release(struct inode *inode, struct file *file)
174 {
175 	struct hfs_readdir_data *rd = file->private_data;
176 	if (rd) {
177 		list_del(&rd->list);
178 		kfree(rd);
179 	}
180 	return 0;
181 }
182 
183 /*
184  * hfs_create()
185  *
186  * This is the create() entry in the inode_operations structure for
187  * regular HFS directories.  The purpose is to create a new file in
188  * a directory and return a corresponding inode, given the inode for
189  * the directory and the name (and its length) of the new file.
190  */
191 static int hfs_create(struct inode *dir, struct dentry *dentry, int mode,
192 		      struct nameidata *nd)
193 {
194 	struct inode *inode;
195 	int res;
196 
197 	inode = hfs_new_inode(dir, &dentry->d_name, mode);
198 	if (!inode)
199 		return -ENOSPC;
200 
201 	res = hfs_cat_create(inode->i_ino, dir, &dentry->d_name, inode);
202 	if (res) {
203 		inode->i_nlink = 0;
204 		hfs_delete_inode(inode);
205 		iput(inode);
206 		return res;
207 	}
208 	d_instantiate(dentry, inode);
209 	mark_inode_dirty(inode);
210 	return 0;
211 }
212 
213 /*
214  * hfs_mkdir()
215  *
216  * This is the mkdir() entry in the inode_operations structure for
217  * regular HFS directories.  The purpose is to create a new directory
218  * in a directory, given the inode for the parent directory and the
219  * name (and its length) of the new directory.
220  */
221 static int hfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
222 {
223 	struct inode *inode;
224 	int res;
225 
226 	inode = hfs_new_inode(dir, &dentry->d_name, S_IFDIR | mode);
227 	if (!inode)
228 		return -ENOSPC;
229 
230 	res = hfs_cat_create(inode->i_ino, dir, &dentry->d_name, inode);
231 	if (res) {
232 		inode->i_nlink = 0;
233 		hfs_delete_inode(inode);
234 		iput(inode);
235 		return res;
236 	}
237 	d_instantiate(dentry, inode);
238 	mark_inode_dirty(inode);
239 	return 0;
240 }
241 
242 /*
243  * hfs_unlink()
244  *
245  * This is the unlink() entry in the inode_operations structure for
246  * regular HFS directories.  The purpose is to delete an existing
247  * file, given the inode for the parent directory and the name
248  * (and its length) of the existing file.
249  */
250 static int hfs_unlink(struct inode *dir, struct dentry *dentry)
251 {
252 	struct inode *inode;
253 	int res;
254 
255 	inode = dentry->d_inode;
256 	res = hfs_cat_delete(inode->i_ino, dir, &dentry->d_name);
257 	if (res)
258 		return res;
259 
260 	drop_nlink(inode);
261 	hfs_delete_inode(inode);
262 	inode->i_ctime = CURRENT_TIME_SEC;
263 	mark_inode_dirty(inode);
264 
265 	return res;
266 }
267 
268 /*
269  * hfs_rmdir()
270  *
271  * This is the rmdir() entry in the inode_operations structure for
272  * regular HFS directories.  The purpose is to delete an existing
273  * directory, given the inode for the parent directory and the name
274  * (and its length) of the existing directory.
275  */
276 static int hfs_rmdir(struct inode *dir, struct dentry *dentry)
277 {
278 	struct inode *inode;
279 	int res;
280 
281 	inode = dentry->d_inode;
282 	if (inode->i_size != 2)
283 		return -ENOTEMPTY;
284 	res = hfs_cat_delete(inode->i_ino, dir, &dentry->d_name);
285 	if (res)
286 		return res;
287 	clear_nlink(inode);
288 	inode->i_ctime = CURRENT_TIME_SEC;
289 	hfs_delete_inode(inode);
290 	mark_inode_dirty(inode);
291 	return 0;
292 }
293 
294 /*
295  * hfs_rename()
296  *
297  * This is the rename() entry in the inode_operations structure for
298  * regular HFS directories.  The purpose is to rename an existing
299  * file or directory, given the inode for the current directory and
300  * the name (and its length) of the existing file/directory and the
301  * inode for the new directory and the name (and its length) of the
302  * new file/directory.
303  * XXX: how do you handle must_be dir?
304  */
305 static int hfs_rename(struct inode *old_dir, struct dentry *old_dentry,
306 		      struct inode *new_dir, struct dentry *new_dentry)
307 {
308 	int res;
309 
310 	/* Unlink destination if it already exists */
311 	if (new_dentry->d_inode) {
312 		res = hfs_unlink(new_dir, new_dentry);
313 		if (res)
314 			return res;
315 	}
316 
317 	res = hfs_cat_move(old_dentry->d_inode->i_ino,
318 			   old_dir, &old_dentry->d_name,
319 			   new_dir, &new_dentry->d_name);
320 	if (!res)
321 		hfs_cat_build_key(old_dir->i_sb,
322 				  (btree_key *)&HFS_I(old_dentry->d_inode)->cat_key,
323 				  new_dir->i_ino, &new_dentry->d_name);
324 	return res;
325 }
326 
327 const struct file_operations hfs_dir_operations = {
328 	.read		= generic_read_dir,
329 	.readdir	= hfs_readdir,
330 	.llseek		= generic_file_llseek,
331 	.release	= hfs_dir_release,
332 };
333 
334 const struct inode_operations hfs_dir_inode_operations = {
335 	.create		= hfs_create,
336 	.lookup		= hfs_lookup,
337 	.unlink		= hfs_unlink,
338 	.mkdir		= hfs_mkdir,
339 	.rmdir		= hfs_rmdir,
340 	.rename		= hfs_rename,
341 	.setattr	= hfs_inode_setattr,
342 };
343