xref: /linux/fs/hfs/dir.c (revision 8fa5723aa7e053d498336b48448b292fc2e0458b)
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 		hfs_bnode_read(fd.bnode, &entry, fd.entryoffset, fd.entrylength);
83 		if (entry.type != HFS_CDR_THD) {
84 			printk(KERN_ERR "hfs: bad catalog folder thread\n");
85 			err = -EIO;
86 			goto out;
87 		}
88 		//if (fd.entrylength < HFS_MIN_THREAD_SZ) {
89 		//	printk(KERN_ERR "hfs: truncated catalog thread\n");
90 		//	err = -EIO;
91 		//	goto out;
92 		//}
93 		if (filldir(dirent, "..", 2, 1,
94 			    be32_to_cpu(entry.thread.ParID), DT_DIR))
95 			goto out;
96 		filp->f_pos++;
97 		/* fall through */
98 	default:
99 		if (filp->f_pos >= inode->i_size)
100 			goto out;
101 		err = hfs_brec_goto(&fd, filp->f_pos - 1);
102 		if (err)
103 			goto out;
104 	}
105 
106 	for (;;) {
107 		if (be32_to_cpu(fd.key->cat.ParID) != inode->i_ino) {
108 			printk(KERN_ERR "hfs: walked past end of dir\n");
109 			err = -EIO;
110 			goto out;
111 		}
112 		hfs_bnode_read(fd.bnode, &entry, fd.entryoffset, fd.entrylength);
113 		type = entry.type;
114 		len = hfs_mac2asc(sb, strbuf, &fd.key->cat.CName);
115 		if (type == HFS_CDR_DIR) {
116 			if (fd.entrylength < sizeof(struct hfs_cat_dir)) {
117 				printk(KERN_ERR "hfs: small dir entry\n");
118 				err = -EIO;
119 				goto out;
120 			}
121 			if (filldir(dirent, strbuf, len, filp->f_pos,
122 				    be32_to_cpu(entry.dir.DirID), DT_DIR))
123 				break;
124 		} else if (type == HFS_CDR_FIL) {
125 			if (fd.entrylength < sizeof(struct hfs_cat_file)) {
126 				printk(KERN_ERR "hfs: small file entry\n");
127 				err = -EIO;
128 				goto out;
129 			}
130 			if (filldir(dirent, strbuf, len, filp->f_pos,
131 				    be32_to_cpu(entry.file.FlNum), DT_REG))
132 				break;
133 		} else {
134 			printk(KERN_ERR "hfs: bad catalog entry type %d\n", type);
135 			err = -EIO;
136 			goto out;
137 		}
138 		filp->f_pos++;
139 		if (filp->f_pos >= inode->i_size)
140 			goto out;
141 		err = hfs_brec_goto(&fd, 1);
142 		if (err)
143 			goto out;
144 	}
145 	rd = filp->private_data;
146 	if (!rd) {
147 		rd = kmalloc(sizeof(struct hfs_readdir_data), GFP_KERNEL);
148 		if (!rd) {
149 			err = -ENOMEM;
150 			goto out;
151 		}
152 		filp->private_data = rd;
153 		rd->file = filp;
154 		list_add(&rd->list, &HFS_I(inode)->open_dir_list);
155 	}
156 	memcpy(&rd->key, &fd.key, sizeof(struct hfs_cat_key));
157 out:
158 	hfs_find_exit(&fd);
159 	return err;
160 }
161 
162 static int hfs_dir_release(struct inode *inode, struct file *file)
163 {
164 	struct hfs_readdir_data *rd = file->private_data;
165 	if (rd) {
166 		list_del(&rd->list);
167 		kfree(rd);
168 	}
169 	return 0;
170 }
171 
172 /*
173  * hfs_create()
174  *
175  * This is the create() entry in the inode_operations structure for
176  * regular HFS directories.  The purpose is to create a new file in
177  * a directory and return a corresponding inode, given the inode for
178  * the directory and the name (and its length) of the new file.
179  */
180 static int hfs_create(struct inode *dir, struct dentry *dentry, int mode,
181 		      struct nameidata *nd)
182 {
183 	struct inode *inode;
184 	int res;
185 
186 	inode = hfs_new_inode(dir, &dentry->d_name, mode);
187 	if (!inode)
188 		return -ENOSPC;
189 
190 	res = hfs_cat_create(inode->i_ino, dir, &dentry->d_name, inode);
191 	if (res) {
192 		inode->i_nlink = 0;
193 		hfs_delete_inode(inode);
194 		iput(inode);
195 		return res;
196 	}
197 	d_instantiate(dentry, inode);
198 	mark_inode_dirty(inode);
199 	return 0;
200 }
201 
202 /*
203  * hfs_mkdir()
204  *
205  * This is the mkdir() entry in the inode_operations structure for
206  * regular HFS directories.  The purpose is to create a new directory
207  * in a directory, given the inode for the parent directory and the
208  * name (and its length) of the new directory.
209  */
210 static int hfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
211 {
212 	struct inode *inode;
213 	int res;
214 
215 	inode = hfs_new_inode(dir, &dentry->d_name, S_IFDIR | mode);
216 	if (!inode)
217 		return -ENOSPC;
218 
219 	res = hfs_cat_create(inode->i_ino, dir, &dentry->d_name, inode);
220 	if (res) {
221 		inode->i_nlink = 0;
222 		hfs_delete_inode(inode);
223 		iput(inode);
224 		return res;
225 	}
226 	d_instantiate(dentry, inode);
227 	mark_inode_dirty(inode);
228 	return 0;
229 }
230 
231 /*
232  * hfs_unlink()
233  *
234  * This is the unlink() entry in the inode_operations structure for
235  * regular HFS directories.  The purpose is to delete an existing
236  * file, given the inode for the parent directory and the name
237  * (and its length) of the existing file.
238  */
239 static int hfs_unlink(struct inode *dir, struct dentry *dentry)
240 {
241 	struct inode *inode;
242 	int res;
243 
244 	inode = dentry->d_inode;
245 	res = hfs_cat_delete(inode->i_ino, dir, &dentry->d_name);
246 	if (res)
247 		return res;
248 
249 	drop_nlink(inode);
250 	hfs_delete_inode(inode);
251 	inode->i_ctime = CURRENT_TIME_SEC;
252 	mark_inode_dirty(inode);
253 
254 	return res;
255 }
256 
257 /*
258  * hfs_rmdir()
259  *
260  * This is the rmdir() entry in the inode_operations structure for
261  * regular HFS directories.  The purpose is to delete an existing
262  * directory, given the inode for the parent directory and the name
263  * (and its length) of the existing directory.
264  */
265 static int hfs_rmdir(struct inode *dir, struct dentry *dentry)
266 {
267 	struct inode *inode;
268 	int res;
269 
270 	inode = dentry->d_inode;
271 	if (inode->i_size != 2)
272 		return -ENOTEMPTY;
273 	res = hfs_cat_delete(inode->i_ino, dir, &dentry->d_name);
274 	if (res)
275 		return res;
276 	clear_nlink(inode);
277 	inode->i_ctime = CURRENT_TIME_SEC;
278 	hfs_delete_inode(inode);
279 	mark_inode_dirty(inode);
280 	return 0;
281 }
282 
283 /*
284  * hfs_rename()
285  *
286  * This is the rename() entry in the inode_operations structure for
287  * regular HFS directories.  The purpose is to rename an existing
288  * file or directory, given the inode for the current directory and
289  * the name (and its length) of the existing file/directory and the
290  * inode for the new directory and the name (and its length) of the
291  * new file/directory.
292  * XXX: how do you handle must_be dir?
293  */
294 static int hfs_rename(struct inode *old_dir, struct dentry *old_dentry,
295 		      struct inode *new_dir, struct dentry *new_dentry)
296 {
297 	int res;
298 
299 	/* Unlink destination if it already exists */
300 	if (new_dentry->d_inode) {
301 		res = hfs_unlink(new_dir, new_dentry);
302 		if (res)
303 			return res;
304 	}
305 
306 	res = hfs_cat_move(old_dentry->d_inode->i_ino,
307 			   old_dir, &old_dentry->d_name,
308 			   new_dir, &new_dentry->d_name);
309 	if (!res)
310 		hfs_cat_build_key(old_dir->i_sb,
311 				  (btree_key *)&HFS_I(old_dentry->d_inode)->cat_key,
312 				  new_dir->i_ino, &new_dentry->d_name);
313 	return res;
314 }
315 
316 const struct file_operations hfs_dir_operations = {
317 	.read		= generic_read_dir,
318 	.readdir	= hfs_readdir,
319 	.llseek		= generic_file_llseek,
320 	.release	= hfs_dir_release,
321 };
322 
323 const struct inode_operations hfs_dir_inode_operations = {
324 	.create		= hfs_create,
325 	.lookup		= hfs_lookup,
326 	.unlink		= hfs_unlink,
327 	.mkdir		= hfs_mkdir,
328 	.rmdir		= hfs_rmdir,
329 	.rename		= hfs_rename,
330 	.setattr	= hfs_inode_setattr,
331 };
332