summaryrefslogtreecommitdiffstats
path: root/include/linux/inotify.h
blob: 72ef82120512a3ea7be7f893f3f7717726103146 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
/*
 * Inode based directory notification for Linux
 *
 * Copyright (C) 2005 John McCutchan
 */

#ifndef _LINUX_INOTIFY_H
#define _LINUX_INOTIFY_H

/* For O_CLOEXEC */
#include <linux/fcntl.h>
#include <linux/types.h>

/*
 * struct inotify_event - structure read from the inotify device for each event
 *
 * When you are watching a directory, you will receive the filename for events
 * such as IN_CREATE, IN_DELETE, IN_OPEN, IN_CLOSE, ..., relative to the wd.
 */
struct inotify_event {
	__s32		wd;		/* watch descriptor */
	__u32		mask;		/* watch mask */
	__u32		cookie;		/* cookie to synchronize two events */
	__u32		len;		/* length (including nulls) of name */
	char		name[0];	/* stub for possible name */
};

/* the following are legal, implemented events that user-space can watch for */
#define IN_ACCESS		0x00000001	/* File was accessed */
#define IN_MODIFY		0x00000002	/* File was modified */
#define IN_ATTRIB		0x00000004	/* Metadata changed */
#define IN_CLOSE_WRITE		0x00000008	/* Writtable file was closed */
#define IN_CLOSE_NOWRITE	0x00000010	/* Unwrittable file closed */
#define IN_OPEN			0x00000020	/* File was opened */
#define IN_MOVED_FROM		0x00000040	/* File was moved from X */
#define IN_MOVED_TO		0x00000080	/* File was moved to Y */
#define IN_CREATE		0x00000100	/* Subfile was created */
#define IN_DELETE		0x00000200	/* Subfile was deleted */
#define IN_DELETE_SELF		0x00000400	/* Self was deleted */
#define IN_MOVE_SELF		0x00000800	/* Self was moved */

/* the following are legal events.  they are sent as needed to any watch */
#define IN_UNMOUNT		0x00002000	/* Backing fs was unmounted */
#define IN_Q_OVERFLOW		0x00004000	/* Event queued overflowed */
#define IN_IGNORED		0x00008000	/* File was ignored */

/* helper events */
#define IN_CLOSE		(IN_CLOSE_WRITE | IN_CLOSE_NOWRITE) /* close */
#define IN_MOVE			(IN_MOVED_FROM | IN_MOVED_TO) /* moves */

/* special flags */
#define IN_ONLYDIR		0x01000000	/* only watch the path if it is a directory */
#define IN_DONT_FOLLOW		0x02000000	/* don't follow a sym link */
#define IN_MASK_ADD		0x20000000	/* add to the mask of an already existing watch */
#define IN_ISDIR		0x40000000	/* event occurred against dir */
#define IN_ONESHOT		0x80000000	/* only send event once */

/*
 * All of the events - we build the list by hand so that we can add flags in
 * the future and not break backward compatibility.  Apps will get only the
 * events that they originally wanted.  Be sure to add new events here!
 */
#define IN_ALL_EVENTS	(IN_ACCESS | IN_MODIFY | IN_ATTRIB | IN_CLOSE_WRITE | \
			 IN_CLOSE_NOWRITE | IN_OPEN | IN_MOVED_FROM | \
			 IN_MOVED_TO | IN_DELETE | IN_CREATE | IN_DELETE_SELF | \
			 IN_MOVE_SELF)

/* Flags for sys_inotify_init1.  */
#define IN_CLOEXEC O_CLOEXEC

#ifdef __KERNEL__

#include <linux/dcache.h>
#include <linux/fs.h>

/*
 * struct inotify_watch - represents a watch request on a specific inode
 *
 * h_list is protected by ih->mutex of the associated inotify_handle.
 * i_list, mask are protected by inode->inotify_mutex of the associated inode.
 * ih, inode, and wd are never written to once the watch is created.
 *
 * Callers must use the established inotify interfaces to access inotify_watch
 * contents.  The content of this structure is private to the inotify
 * implementation.
 */
struct inotify_watch {
	struct list_head	h_list;	/* entry in inotify_handle's list */
	struct list_head	i_list;	/* entry in inode's list */
	atomic_t		count;	/* reference count */
	struct inotify_handle	*ih;	/* associated inotify handle */
	struct inode		*inode;	/* associated inode */
	__s32			wd;	/* watch descriptor */
	__u32			mask;	/* event mask for this watch */
};

struct inotify_operations {
	void (*handle_event)(struct inotify_watch *, u32, u32, u32,
			     const char *, struct inode *);
	void (*destroy_watch)(struct inotify_watch *);
};

#ifdef CONFIG_INOTIFY

/* Kernel API for producing events */

extern void inotify_d_instantiate(struct dentry *, struct inode *);
extern void inotify_d_move(struct dentry *);
extern void inotify_inode_queue_event(struct inode *, __u32, __u32,
				      const char *, struct inode *);
extern void inotify_dentry_parent_queue_event(struct dentry *, __u32, __u32,
					      const char *);
extern void inotify_unmount_inodes(struct list_head *);
extern void inotify_inode_is_dead(struct inode *);
extern u32 inotify_get_cookie(void);

/* Kernel Consumer API */

extern struct inotify_handle *inotify_init(const struct inotify_operations *);
extern void inotify_init_watch(struct inotify_watch *);
extern void inotify_destroy(struct inotify_handle *);
extern __s32 inotify_find_watch(struct inotify_handle *, struct inode *,
				struct inotify_watch **);
extern __s32 inotify_find_update_watch(struct inotify_handle *, struct inode *,
				       u32);
extern __s32 inotify_add_watch(struct inotify_handle *, struct inotify_watch *,
			       struct inode *, __u32);
extern __s32 inotify_clone_watch(struct inotify_watch *, struct inotify_watch *);
extern void inotify_evict_watch(struct inotify_watch *);
extern int inotify_rm_watch(struct inotify_handle *, struct inotify_watch *);
extern int inotify_rm_wd(struct inotify_handle *, __u32);
extern void inotify_remove_watch_locked(struct inotify_handle *,
					struct inotify_watch *);
extern void get_inotify_watch(struct inotify_watch *);
extern void put_inotify_watch(struct inotify_watch *);

#else

static inline void inotify_d_instantiate(struct dentry *dentry,
					struct inode *inode)
{
}

static inline void inotify_d_move(struct dentry *dentry)
{
}

static inline void inotify_inode_queue_event(struct inode *inode,
					     __u32 mask, __u32 cookie,
					     const char *filename,
					     struct inode *n_inode)
{
}

static inline void inotify_dentry_parent_queue_event(struct dentry *dentry,
						     __u32 mask, __u32 cookie,
						     const char *filename)
{
}

static inline void inotify_unmount_inodes(struct list_head *list)
{
}

static inline void inotify_inode_is_dead(struct inode *inode)
{
}

static inline u32 inotify_get_cookie(void)
{
	return 0;
}

static inline struct inotify_handle *inotify_init(const struct inotify_operations *ops)
{
	return ERR_PTR(-EOPNOTSUPP);
}

static inline void inotify_init_watch(struct inotify_watch *watch)
{
}

static inline void inotify_destroy(struct inotify_handle *ih)
{
}

static inline __s32 inotify_find_watch(struct inotify_handle *ih, struct inode *inode,
				       struct inotify_watch **watchp)
{
	return -EOPNOTSUPP;
}

static inline __s32 inotify_find_update_watch(struct inotify_handle *ih,
					      struct inode *inode, u32 mask)
{
	return -EOPNOTSUPP;
}

static inline __s32 inotify_add_watch(struct inotify_handle *ih,
				      struct inotify_watch *watch,
				      struct inode *inode, __u32 mask)
{
	return -EOPNOTSUPP;
}

static inline int inotify_rm_watch(struct inotify_handle *ih,
				   struct inotify_watch *watch)
{
	return -EOPNOTSUPP;
}

static inline int inotify_rm_wd(struct inotify_handle *ih, __u32 wd)
{
	return -EOPNOTSUPP;
}

static inline void inotify_remove_watch_locked(struct inotify_handle *ih,
					       struct inotify_watch *watch)
{
}

static inline void get_inotify_watch(struct inotify_watch *watch)
{
}

static inline void put_inotify_watch(struct inotify_watch *watch)
{
}

#endif	/* CONFIG_INOTIFY */

#endif	/* __KERNEL __ */

#endif	/* _LINUX_INOTIFY_H */