xref: /dragonfly/sys/sys/event.h (revision 78478697)
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 #ifndef _NET_NETISR_H_
37 #include <net/netisr.h>			/* struct notifymsglist */
38 #endif
39 #if defined(_KERNEL) || defined(_KERNEL_STRUCTURES)
40 #include <sys/queue.h>
41 #endif
42 
43 #define EVFILT_READ		(-1)
44 #define EVFILT_WRITE		(-2)
45 #define EVFILT_AIO		(-3)	/* attached to aio requests */
46 #define EVFILT_VNODE		(-4)	/* attached to vnodes */
47 #define EVFILT_PROC		(-5)	/* attached to struct proc */
48 #define EVFILT_SIGNAL		(-6)	/* attached to struct proc */
49 #define EVFILT_TIMER		(-7)	/* timers */
50 #define EVFILT_EXCEPT		(-8)	/* exceptional conditions */
51 #define EVFILT_USER		(-9)	/* user events */
52 
53 #define EVFILT_MARKER		0xF	/* placemarker for tailq */
54 
55 #define EVFILT_SYSCOUNT		9
56 
57 #define EV_SET(kevp_, a, b, c, d, e, f) do {	\
58 	struct kevent *kevp = (kevp_);		\
59 	(kevp)->ident = (a);			\
60 	(kevp)->filter = (b);			\
61 	(kevp)->flags = (c);			\
62 	(kevp)->fflags = (d);			\
63 	(kevp)->data = (e);			\
64 	(kevp)->udata = (f);			\
65 } while(0)
66 
67 struct kevent {
68 	uintptr_t	ident;		/* identifier for this event */
69 	short		filter;		/* filter for event */
70 	u_short		flags;
71 	u_int		fflags;
72 	intptr_t	data;
73 	void		*udata;		/* opaque user data identifier */
74 };
75 
76 /* actions */
77 #define EV_ADD		0x0001		/* add event to kq (implies enable) */
78 #define EV_DELETE	0x0002		/* delete event from kq */
79 #define EV_ENABLE	0x0004		/* enable event */
80 #define EV_DISABLE	0x0008		/* disable event (not reported) */
81 
82 /* flags */
83 #define EV_ONESHOT	0x0010		/* only report one occurrence */
84 #define EV_CLEAR	0x0020		/* clear event state after reporting */
85 #define EV_RECEIPT	0x0040		/* force EV_ERROR on success, data=0 */
86 #define EV_DISPATCH	0x0080		/* disable event after reporting */
87 
88 #define EV_SYSFLAGS	0xF000		/* reserved by system */
89 #define EV_FLAG1	0x2000		/* filter-specific flag */
90 
91 /* returned values */
92 #define EV_EOF		0x8000		/* EOF detected */
93 #define EV_ERROR	0x4000		/* error, data contains errno */
94 #define EV_NODATA	0x1000		/* EOF and no more data */
95 
96 /*
97  * EVFILT_USER
98  */
99  /*
100   * data/hint flags/masks for EVFILT_USER, shared with userspace
101   *
102   * On input, the top two bits of fflags specifies how the lower twenty four
103   * bits should be applied to the stored value of fflags.
104   *
105   * On output, the top two bits will always be set to NOTE_FFNOP and the
106   * remaining twenty four bits will contain the stored fflags value.
107   */
108 #define NOTE_FFNOP      0x00000000	/* ignore input fflags */
109 #define NOTE_FFAND      0x40000000	/* AND fflags */
110 #define NOTE_FFOR       0x80000000	/* OR fflags */
111 #define NOTE_FFCOPY     0xc0000000	/* copy fflags */
112 #define NOTE_FFCTRLMASK 0xc0000000	/* masks for operations */
113 #define NOTE_FFLAGSMASK 0x00ffffff
114 
115 #define NOTE_TRIGGER    0x01000000	/* trigger for output */
116 
117 /*
118  * data/hint flags for EVFILT_{READ|WRITE}, shared with userspace
119  */
120 #define NOTE_LOWAT	0x0001			/* low water mark */
121 
122 /*
123  * data/hint flags for EVFILT_EXCEPT, shared with userspace and with
124  * EVFILT_{READ|WRITE}
125  */
126 #define NOTE_OOB	0x0002			/* OOB data on a socket */
127 
128 /*
129  * data/hint flags for EVFILT_VNODE, shared with userspace
130  */
131 #define	NOTE_DELETE	0x0001			/* vnode was removed */
132 #define	NOTE_WRITE	0x0002			/* data contents changed */
133 #define	NOTE_EXTEND	0x0004			/* size increased */
134 #define	NOTE_ATTRIB	0x0008			/* attributes changed */
135 #define	NOTE_LINK	0x0010			/* link count changed */
136 #define	NOTE_RENAME	0x0020			/* vnode was renamed */
137 #define	NOTE_REVOKE	0x0040			/* vnode access was revoked */
138 
139 /*
140  * data/hint flags for EVFILT_PROC, shared with userspace
141  */
142 #define	NOTE_EXIT	0x80000000		/* process exited */
143 #define	NOTE_FORK	0x40000000		/* process forked */
144 #define	NOTE_EXEC	0x20000000		/* process exec'd */
145 #define	NOTE_PCTRLMASK	0xf0000000		/* mask for hint bits */
146 #define	NOTE_PDATAMASK	0x000fffff		/* mask for pid */
147 
148 /* additional flags for EVFILT_PROC */
149 #define	NOTE_TRACK	0x00000001		/* follow across forks */
150 #define	NOTE_TRACKERR	0x00000002		/* could not track child */
151 #define	NOTE_CHILD	0x00000004		/* am a child process */
152 
153 #if defined(_KERNEL) || defined(_KERNEL_STRUCTURES)
154 
155 struct knote;
156 SLIST_HEAD(klist, knote);
157 
158 /*
159  * Used to maintain information about processes that wish to be
160  * notified when I/O becomes possible.
161  */
162 struct kqinfo {
163 	struct	klist ki_note;		/* kernel note list */
164 	struct	notifymsglist ki_mlist;	/* list of pending predicate messages */
165 };
166 
167 #endif
168 
169 #ifdef _KERNEL
170 
171 /*
172  * Global token for kqueue subsystem
173  */
174 extern struct lwkt_token kq_token;
175 
176 #ifdef MALLOC_DECLARE
177 MALLOC_DECLARE(M_KQUEUE);
178 #endif
179 
180 #define KNOTE(list, hint)	if (!SLIST_EMPTY((list))) knote(list, hint)
181 
182 /*
183  * Flag indicating hint is a signal.  Used by EVFILT_SIGNAL, and also
184  * shared by EVFILT_PROC  (all knotes attached to p->p_klist)
185  *
186  * NOTE_OLDAPI is used to signal that standard filters are being called
187  * from the select/poll wrapper.
188  */
189 #define NOTE_SIGNAL	0x08000000
190 #define NOTE_OLDAPI	0x04000000	/* select/poll note */
191 
192 #define FILTEROP_ISFD	0x0001		/* if ident == filedescriptor */
193 #define FILTEROP_MPSAFE	0x0002
194 
195 struct filterops {
196 	u_short	f_flags;
197 
198 	/* f_attach returns 0 on success or valid error code on failure */
199 	int	(*f_attach)	(struct knote *kn);
200 	void	(*f_detach)	(struct knote *kn);
201 
202         /* f_event returns boolean truth */
203 	int	(*f_event)	(struct knote *kn, long hint);
204 };
205 
206 struct knote {
207 	SLIST_ENTRY(knote)	kn_link;	/* for fd */
208 	TAILQ_ENTRY(knote)	kn_kqlink;	/* for kq_knlist */
209 	SLIST_ENTRY(knote)	kn_next;	/* for struct kqinfo */
210 	TAILQ_ENTRY(knote)	kn_tqe;		/* for kq_knpend */
211 	struct			kqueue *kn_kq;	/* which queue we are on */
212 	struct 			kevent kn_kevent;
213 	int			kn_status;
214 	int			kn_sfflags;	/* saved filter flags */
215 	intptr_t		kn_sdata;	/* saved data field */
216 	union {
217 		struct		file *p_fp;	/* file data pointer */
218 		struct		proc *p_proc;	/* proc pointer */
219 		int		hookid;
220 	} kn_ptr;
221 	struct			filterops *kn_fop;
222 	caddr_t			kn_hook;
223 };
224 
225 #define KN_ACTIVE	0x0001			/* event has been triggered */
226 #define KN_QUEUED	0x0002			/* event is on queue */
227 #define KN_DISABLED	0x0004			/* event is disabled */
228 #define KN_DETACHED	0x0008			/* knote is detached */
229 #define KN_REPROCESS	0x0010			/* force reprocessing race */
230 #define KN_DELETING	0x0020			/* deletion in progress */
231 #define KN_PROCESSING	0x0040			/* event processing in prog */
232 #define KN_WAITING	0x0080			/* waiting on processing */
233 
234 #define kn_id		kn_kevent.ident
235 #define kn_filter	kn_kevent.filter
236 #define kn_flags	kn_kevent.flags
237 #define kn_fflags	kn_kevent.fflags
238 #define kn_data		kn_kevent.data
239 #define kn_fp		kn_ptr.p_fp
240 
241 struct proc;
242 struct thread;
243 struct filedesc;
244 struct kevent_args;
245 
246 typedef int	(*k_copyout_fn)(void *arg, struct kevent *kevp, int count,
247     int *res);
248 typedef int	(*k_copyin_fn)(void *arg, struct kevent *kevp, int max,
249     int *events);
250 int kern_kevent(struct kqueue *kq, int nevents, int *res, void *uap,
251     k_copyin_fn kevent_copyin, k_copyout_fn kevent_copyout,
252     struct timespec *tsp);
253 
254 extern void	knote(struct klist *list, long hint);
255 extern void	knote_insert(struct klist *klist, struct knote *kn);
256 extern void	knote_remove(struct klist *klist, struct knote *kn);
257 /*extern void	knote_empty(struct klist *list);*/
258 extern void	knote_assume_knotes(struct kqinfo *, struct kqinfo *,
259 		    struct filterops *, void *);
260 extern void	knote_fdclose(struct file *fp, struct filedesc *fdp, int fd);
261 extern void	kqueue_init(struct kqueue *kq, struct filedesc *fdp);
262 extern void	kqueue_terminate(struct kqueue *kq);
263 extern int 	kqueue_register(struct kqueue *kq, struct kevent *kev);
264 
265 #endif 	/* _KERNEL */
266 
267 #if !defined(_KERNEL) || defined(_KERNEL_VIRTUAL)
268 
269 #include <sys/cdefs.h>
270 struct timespec;
271 
272 __BEGIN_DECLS
273 int     kqueue (void);
274 int     kevent (int, const struct kevent *, int, struct kevent *,
275 		int, const struct timespec *);
276 __END_DECLS
277 #endif /* !_KERNEL */
278 
279 #endif /* !_SYS_EVENT_H_ */
280