xref: /dragonfly/sys/sys/event.h (revision caa7a3ee)
1 /*-
2  * Copyright (c) 1999,2000,2001 Jonathan Lemon <jlemon@FreeBSD.org>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  *
26  *	$FreeBSD: src/sys/sys/event.h,v 1.5.2.6 2003/02/09 15:28:13 nectar Exp $
27  *	$DragonFly: src/sys/sys/event.h,v 1.7 2007/01/15 01:26:56 dillon Exp $
28  */
29 
30 #ifndef _SYS_EVENT_H_
31 #define _SYS_EVENT_H_
32 
33 #ifndef _SYS_TYPES_H_
34 #include <sys/types.h>
35 #endif
36 #if defined(_KERNEL) || defined(_KERNEL_STRUCTURES)
37 #include <sys/queue.h>
38 #endif
39 
40 #define EVFILT_READ		(-1)
41 #define EVFILT_WRITE		(-2)
42 #define EVFILT_AIO		(-3)	/* attached to aio requests */
43 #define EVFILT_VNODE		(-4)	/* attached to vnodes */
44 #define EVFILT_PROC		(-5)	/* attached to struct proc */
45 #define EVFILT_SIGNAL		(-6)	/* attached to struct proc */
46 #define EVFILT_TIMER		(-7)	/* timers */
47 #define EVFILT_EXCEPT		(-8)	/* exceptional conditions */
48 #define EVFILT_USER		(-9)	/* user events */
49 
50 #define EVFILT_MARKER		0xF	/* placemarker for tailq */
51 
52 #define EVFILT_SYSCOUNT		9
53 
54 #define EV_SET(kevp_, a, b, c, d, e, f) do {	\
55 	struct kevent *kevp = (kevp_);		\
56 	(kevp)->ident = (a);			\
57 	(kevp)->filter = (b);			\
58 	(kevp)->flags = (c);			\
59 	(kevp)->fflags = (d);			\
60 	(kevp)->data = (e);			\
61 	(kevp)->udata = (f);			\
62 } while(0)
63 
64 struct kevent {
65 	uintptr_t	ident;		/* identifier for this event */
66 	short		filter;		/* filter for event */
67 	u_short		flags;
68 	u_int		fflags;
69 	intptr_t	data;
70 	void		*udata;		/* opaque user data identifier */
71 };
72 
73 /* actions */
74 #define EV_ADD		0x0001		/* add event to kq (implies enable) */
75 #define EV_DELETE	0x0002		/* delete event from kq */
76 #define EV_ENABLE	0x0004		/* enable event */
77 #define EV_DISABLE	0x0008		/* disable event (not reported) */
78 
79 /* flags */
80 #define EV_ONESHOT	0x0010		/* only report one occurrence */
81 #define EV_CLEAR	0x0020		/* clear event state after reporting */
82 #define EV_RECEIPT	0x0040		/* force EV_ERROR on success, data=0 */
83 #define EV_DISPATCH	0x0080		/* disable event after reporting */
84 
85 #define EV_SYSFLAGS	0xF000		/* reserved by system */
86 #define EV_FLAG1	0x2000		/* filter-specific flag */
87 
88 /* returned values */
89 #define EV_EOF		0x8000		/* EOF detected */
90 #define EV_ERROR	0x4000		/* error, data contains errno */
91 #define EV_NODATA	0x1000		/* EOF and no more data */
92 
93 /*
94  * EVFILT_USER
95  */
96  /*
97   * data/hint flags/masks for EVFILT_USER, shared with userspace
98   *
99   * On input, the top two bits of fflags specifies how the lower twenty four
100   * bits should be applied to the stored value of fflags.
101   *
102   * On output, the top two bits will always be set to NOTE_FFNOP and the
103   * remaining twenty four bits will contain the stored fflags value.
104   */
105 #define NOTE_FFNOP      0x00000000	/* ignore input fflags */
106 #define NOTE_FFAND      0x40000000	/* AND fflags */
107 #define NOTE_FFOR       0x80000000	/* OR fflags */
108 #define NOTE_FFCOPY     0xc0000000	/* copy fflags */
109 #define NOTE_FFCTRLMASK 0xc0000000	/* masks for operations */
110 #define NOTE_FFLAGSMASK 0x00ffffff
111 
112 #define NOTE_TRIGGER    0x01000000	/* trigger for output */
113 
114 /*
115  * data/hint flags for EVFILT_{READ|WRITE}, shared with userspace
116  */
117 #define NOTE_LOWAT	0x0001			/* low water mark */
118 
119 /*
120  * data/hint flags for EVFILT_EXCEPT, shared with userspace and with
121  * EVFILT_{READ|WRITE}
122  */
123 #define NOTE_OOB	0x0002			/* OOB data on a socket */
124 
125 /*
126  * data/hint flags for EVFILT_VNODE, shared with userspace
127  */
128 #define	NOTE_DELETE	0x0001			/* vnode was removed */
129 #define	NOTE_WRITE	0x0002			/* data contents changed */
130 #define	NOTE_EXTEND	0x0004			/* size increased */
131 #define	NOTE_ATTRIB	0x0008			/* attributes changed */
132 #define	NOTE_LINK	0x0010			/* link count changed */
133 #define	NOTE_RENAME	0x0020			/* vnode was renamed */
134 #define	NOTE_REVOKE	0x0040			/* vnode access was revoked */
135 
136 /*
137  * data/hint flags for EVFILT_PROC, shared with userspace
138  */
139 #define	NOTE_EXIT	0x80000000		/* process exited */
140 #define	NOTE_FORK	0x40000000		/* process forked */
141 #define	NOTE_EXEC	0x20000000		/* process exec'd */
142 #define	NOTE_PCTRLMASK	0xf0000000		/* mask for hint bits */
143 #define	NOTE_PDATAMASK	0x000fffff		/* mask for pid */
144 
145 /* additional flags for EVFILT_PROC */
146 #define	NOTE_TRACK	0x00000001		/* follow across forks */
147 #define	NOTE_TRACKERR	0x00000002		/* could not track child */
148 #define	NOTE_CHILD	0x00000004		/* am a child process */
149 
150 #if defined(_KERNEL) || defined(_KERNEL_STRUCTURES)
151 
152 struct knote;
153 SLIST_HEAD(klist, knote);
154 
155 /*
156  * Used to maintain information about processes that wish to be
157  * notified when I/O becomes possible.
158  */
159 struct kqinfo {
160 	struct	klist ki_note;		/* kernel note list */
161 };
162 
163 #endif
164 
165 #ifdef _KERNEL
166 
167 /*
168  * Global token for kqueue subsystem
169  */
170 extern struct lwkt_token kq_token;
171 
172 #ifdef MALLOC_DECLARE
173 MALLOC_DECLARE(M_KQUEUE);
174 #endif
175 
176 #define KNOTE(list, hint)	if (!SLIST_EMPTY((list))) knote(list, hint)
177 
178 /*
179  * Flag indicating hint is a signal.  Used by EVFILT_SIGNAL, and also
180  * shared by EVFILT_PROC  (all knotes attached to p->p_klist)
181  *
182  * NOTE_OLDAPI is used to signal that standard filters are being called
183  * from the select/poll wrapper.
184  */
185 #define NOTE_SIGNAL	0x08000000
186 #define NOTE_OLDAPI	0x04000000	/* select/poll note */
187 
188 #define FILTEROP_ISFD	0x0001		/* if ident == filedescriptor */
189 #define FILTEROP_MPSAFE	0x0002
190 
191 struct filterops {
192 	u_short	f_flags;
193 
194 	/* f_attach returns 0 on success or valid error code on failure */
195 	int	(*f_attach)	(struct knote *kn);
196 	void	(*f_detach)	(struct knote *kn);
197 
198         /* f_event returns boolean truth */
199 	int	(*f_event)	(struct knote *kn, long hint);
200 };
201 
202 struct knote {
203 	SLIST_ENTRY(knote)	kn_link;	/* for fd */
204 	TAILQ_ENTRY(knote)	kn_kqlink;	/* for kq_knlist */
205 	SLIST_ENTRY(knote)	kn_next;	/* for struct kqinfo */
206 	TAILQ_ENTRY(knote)	kn_tqe;		/* for kq_knpend */
207 	struct			kqueue *kn_kq;	/* which queue we are on */
208 	struct 			kevent kn_kevent;
209 	int			kn_status;
210 	int			kn_sfflags;	/* saved filter flags */
211 	intptr_t		kn_sdata;	/* saved data field */
212 	union {
213 		struct		file *p_fp;	/* file data pointer */
214 		struct		proc *p_proc;	/* proc pointer */
215 		int		hookid;
216 	} kn_ptr;
217 	struct			filterops *kn_fop;
218 	caddr_t			kn_hook;
219 };
220 
221 #define KN_ACTIVE	0x0001			/* event has been triggered */
222 #define KN_QUEUED	0x0002			/* event is on queue */
223 #define KN_DISABLED	0x0004			/* event is disabled */
224 #define KN_DETACHED	0x0008			/* knote is detached */
225 #define KN_REPROCESS	0x0010			/* force reprocessing race */
226 #define KN_DELETING	0x0020			/* deletion in progress */
227 #define KN_PROCESSING	0x0040			/* event processing in prog */
228 #define KN_WAITING	0x0080			/* waiting on processing */
229 
230 #define kn_id		kn_kevent.ident
231 #define kn_filter	kn_kevent.filter
232 #define kn_flags	kn_kevent.flags
233 #define kn_fflags	kn_kevent.fflags
234 #define kn_data		kn_kevent.data
235 #define kn_fp		kn_ptr.p_fp
236 
237 struct proc;
238 struct thread;
239 struct filedesc;
240 struct kevent_args;
241 
242 typedef int	(*k_copyout_fn)(void *arg, struct kevent *kevp, int count,
243     int *res);
244 typedef int	(*k_copyin_fn)(void *arg, struct kevent *kevp, int max,
245     int *events);
246 int kern_kevent(struct kqueue *kq, int nevents, int *res, void *uap,
247     k_copyin_fn kevent_copyin, k_copyout_fn kevent_copyout,
248     struct timespec *tsp);
249 
250 extern void	knote(struct klist *list, long hint);
251 extern void	knote_insert(struct klist *klist, struct knote *kn);
252 extern void	knote_remove(struct klist *klist, struct knote *kn);
253 /*extern void	knote_empty(struct klist *list);*/
254 extern void	knote_assume_knotes(struct kqinfo *, struct kqinfo *,
255 		    struct filterops *, void *);
256 extern void	knote_fdclose(struct file *fp, struct filedesc *fdp, int fd);
257 extern void	kqueue_init(struct kqueue *kq, struct filedesc *fdp);
258 extern void	kqueue_terminate(struct kqueue *kq);
259 extern int 	kqueue_register(struct kqueue *kq, struct kevent *kev);
260 
261 #endif 	/* _KERNEL */
262 
263 #if !defined(_KERNEL) || defined(_KERNEL_VIRTUAL)
264 
265 #include <sys/cdefs.h>
266 struct timespec;
267 
268 __BEGIN_DECLS
269 int     kqueue (void);
270 int     kevent (int, const struct kevent *, int, struct kevent *,
271 		int, const struct timespec *);
272 __END_DECLS
273 #endif /* !_KERNEL */
274 
275 #endif /* !_SYS_EVENT_H_ */
276