1/* $NetBSD: event.h,v 1.26 2016/01/31 04:40:01 christos Exp $ */
2
3/*-
4 * Copyright (c) 1999,2000,2001 Jonathan Lemon <jlemon@FreeBSD.org>
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 *
28 * $FreeBSD: src/sys/sys/event.h,v 1.12 2001/02/24 01:44:03 jlemon Exp $
29 */
30
31#ifndef _SYS_EVENT_H_
32#define _SYS_EVENT_H_
33
34#include <sys/featuretest.h>
35#include <sys/types.h> /* for size_t */
36#include <sys/inttypes.h> /* for uintptr_t */
37#include <sys/null.h> /* for NULL */
38
39#define EVFILT_READ 0U
40#define EVFILT_WRITE 1U
41#define EVFILT_AIO 2U /* attached to aio requests */
42#define EVFILT_VNODE 3U /* attached to vnodes */
43#define EVFILT_PROC 4U /* attached to struct proc */
44#define EVFILT_SIGNAL 5U /* attached to struct proc */
45#define EVFILT_TIMER 6U /* arbitrary timer (in ms) */
46#define EVFILT_SYSCOUNT 7U /* number of filters */
47
48#define EV_SET(kevp, a, b, c, d, e, f) \
49do { \
50 (kevp)->ident = (a); \
51 (kevp)->filter = (b); \
52 (kevp)->flags = (c); \
53 (kevp)->fflags = (d); \
54 (kevp)->data = (e); \
55 (kevp)->udata = (f); \
56} while (/* CONSTCOND */ 0)
57
58
59struct kevent {
60 uintptr_t ident; /* identifier for this event */
61 uint32_t filter; /* filter for event */
62 uint32_t flags; /* action flags for kqueue */
63 uint32_t fflags; /* filter flag value */
64 int64_t data; /* filter data value */
65 intptr_t udata; /* opaque user data identifier */
66};
67
68/* actions */
69#define EV_ADD 0x0001U /* add event to kq (implies ENABLE) */
70#define EV_DELETE 0x0002U /* delete event from kq */
71#define EV_ENABLE 0x0004U /* enable event */
72#define EV_DISABLE 0x0008U /* disable event (not reported) */
73
74/* flags */
75#define EV_ONESHOT 0x0010U /* only report one occurrence */
76#define EV_CLEAR 0x0020U /* clear event state after reporting */
77#define EV_RECEIPT 0x0040U /* force EV_ERROR on success, data=0 */
78#define EV_DISPATCH 0x0080U /* disable event after reporting */
79
80#define EV_SYSFLAGS 0xF000U /* reserved by system */
81#define EV_FLAG1 0x2000U /* filter-specific flag */
82
83/* returned values */
84#define EV_EOF 0x8000U /* EOF detected */
85#define EV_ERROR 0x4000U /* error, data contains errno */
86
87/*
88 * hint flag for in-kernel use - must not equal any existing note
89 */
90#ifdef _KERNEL
91#define NOTE_SUBMIT 0x01000000U /* initial knote submission */
92#endif
93/*
94 * data/hint flags for EVFILT_{READ|WRITE}, shared with userspace
95 */
96#define NOTE_LOWAT 0x0001U /* low water mark */
97
98/*
99 * data/hint flags for EVFILT_VNODE, shared with userspace
100 */
101#define NOTE_DELETE 0x0001U /* vnode was removed */
102#define NOTE_WRITE 0x0002U /* data contents changed */
103#define NOTE_EXTEND 0x0004U /* size increased */
104#define NOTE_ATTRIB 0x0008U /* attributes changed */
105#define NOTE_LINK 0x0010U /* link count changed */
106#define NOTE_RENAME 0x0020U /* vnode was renamed */
107#define NOTE_REVOKE 0x0040U /* vnode access was revoked */
108
109/*
110 * data/hint flags for EVFILT_PROC, shared with userspace
111 */
112#define NOTE_EXIT 0x80000000U /* process exited */
113#define NOTE_FORK 0x40000000U /* process forked */
114#define NOTE_EXEC 0x20000000U /* process exec'd */
115#define NOTE_PCTRLMASK 0xf0000000U /* mask for hint bits */
116#define NOTE_PDATAMASK 0x000fffffU /* mask for pid */
117
118/* additional flags for EVFILT_PROC */
119#define NOTE_TRACK 0x00000001U /* follow across forks */
120#define NOTE_TRACKERR 0x00000002U /* could not track child */
121#define NOTE_CHILD 0x00000004U /* am a child process */
122
123/*
124 * This is currently visible to userland to work around broken
125 * programs which pull in <sys/proc.h> or <sys/select.h>.
126 */
127#include <sys/queue.h>
128struct knote;
129SLIST_HEAD(klist, knote);
130
131
132/*
133 * ioctl(2)s supported on kqueue descriptors.
134 */
135#include <sys/ioctl.h>
136
137struct kfilter_mapping {
138 char *name; /* name to lookup or return */
139 size_t len; /* length of name */
140 uint32_t filter; /* filter to lookup or return */
141};
142
143/* map filter to name (max size len) */
144#define KFILTER_BYFILTER _IOWR('k', 0, struct kfilter_mapping)
145/* map name to filter (len ignored) */
146#define KFILTER_BYNAME _IOWR('k', 1, struct kfilter_mapping)
147
148#ifdef _KERNEL
149
150#define KNOTE(list, hint) if (!SLIST_EMPTY(list)) knote(list, hint)
151
152/*
153 * Flag indicating hint is a signal. Used by EVFILT_SIGNAL, and also
154 * shared by EVFILT_PROC (all knotes attached to p->p_klist)
155 */
156#define NOTE_SIGNAL 0x08000000U
157
158/*
159 * Callback methods for each filter type.
160 */
161struct filterops {
162 int f_isfd; /* true if ident == filedescriptor */
163 int (*f_attach) (struct knote *);
164 /* called when knote is ADDed */
165 void (*f_detach) (struct knote *);
166 /* called when knote is DELETEd */
167 int (*f_event) (struct knote *, long);
168 /* called when event is triggered */
169};
170
171/*
172 * Field locking:
173 *
174 * f kn_kq->kq_fdp->fd_lock
175 * q kn_kq->kq_lock
176 * o object mutex (e.g. device driver or vnode interlock)
177 */
178struct kfilter;
179
180struct knote {
181 SLIST_ENTRY(knote) kn_link; /* f: for fd */
182 SLIST_ENTRY(knote) kn_selnext; /* o: for struct selinfo */
183 TAILQ_ENTRY(knote) kn_tqe; /* q: for struct kqueue */
184 struct kqueue *kn_kq; /* q: which queue we are on */
185 struct kevent kn_kevent;
186 uint32_t kn_status;
187 uint32_t kn_sfflags; /* saved filter flags */
188 uintptr_t kn_sdata; /* saved data field */
189 void *kn_obj; /* pointer to monitored obj */
190 const struct filterops *kn_fop;
191 struct kfilter *kn_kfilter;
192 void *kn_hook;
193
194#define KN_ACTIVE 0x01U /* event has been triggered */
195#define KN_QUEUED 0x02U /* event is on queue */
196#define KN_DISABLED 0x04U /* event is disabled */
197#define KN_DETACHED 0x08U /* knote is detached */
198#define KN_MARKER 0x10U /* is a marker */
199#define KN_BUSY 0x20U /* is being scanned */
200
201#define kn_id kn_kevent.ident
202#define kn_filter kn_kevent.filter
203#define kn_flags kn_kevent.flags
204#define kn_fflags kn_kevent.fflags
205#define kn_data kn_kevent.data
206};
207
208#include <sys/systm.h> /* for copyin_t */
209
210struct lwp;
211struct timespec;
212
213void kqueue_init(void);
214void knote(struct klist *, long);
215void knote_fdclose(int);
216
217typedef int (*kevent_fetch_changes_t)(void *, const struct kevent *,
218 struct kevent *, size_t, int);
219typedef int (*kevent_put_events_t)(void *, struct kevent *, struct kevent *,
220 size_t, int);
221
222struct kevent_ops {
223 void *keo_private;
224 copyin_t keo_fetch_timeout;
225 kevent_fetch_changes_t keo_fetch_changes;
226 kevent_put_events_t keo_put_events;
227};
228
229
230int kevent_fetch_changes(void *, const struct kevent *, struct kevent *,
231 size_t, int);
232int kevent_put_events(void *, struct kevent *, struct kevent *, size_t,
233 int);
234int kevent1(register_t *, int, const struct kevent *,
235 size_t, struct kevent *, size_t, const struct timespec *,
236 const struct kevent_ops *);
237
238int kfilter_register(const char *, const struct filterops *, int *);
239int kfilter_unregister(const char *);
240
241int filt_seltrue(struct knote *, long);
242extern const struct filterops seltrue_filtops;
243
244#else /* !_KERNEL */
245
246#include <sys/cdefs.h>
247struct timespec;
248
249__BEGIN_DECLS
250#if defined(_NETBSD_SOURCE)
251int kqueue(void);
252int kqueue1(int);
253#ifndef __LIBC12_SOURCE__
254int kevent(int, const struct kevent *, size_t, struct kevent *, size_t,
255 const struct timespec *) __RENAME(__kevent50);
256#endif
257#endif /* !_POSIX_C_SOURCE */
258__END_DECLS
259
260#endif /* !_KERNEL */
261
262#endif /* !_SYS_EVENT_H_ */
263