1/*-
2 * SPDX-License-Identifier: BSD-2-Clause
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
29#ifndef _SYS_EVENT_H_
30#define _SYS_EVENT_H_
31
32#include <sys/_types.h>
33#include <sys/queue.h>
34
35#define EVFILT_READ (-1)
36#define EVFILT_WRITE (-2)
37#define EVFILT_AIO (-3) /* attached to aio requests */
38#define EVFILT_VNODE (-4) /* attached to vnodes */
39#define EVFILT_PROC (-5) /* attached to struct proc */
40#define EVFILT_SIGNAL (-6) /* attached to struct proc */
41#define EVFILT_TIMER (-7) /* timers */
42#define EVFILT_PROCDESC (-8) /* attached to process descriptors */
43#define EVFILT_FS (-9) /* filesystem events */
44#define EVFILT_LIO (-10) /* attached to lio requests */
45#define EVFILT_USER (-11) /* User events */
46#define EVFILT_SENDFILE (-12) /* attached to sendfile requests */
47#define EVFILT_EMPTY (-13) /* empty send socket buf */
48#define EVFILT_JAIL (-14) /* attached to struct prison */
49#define EVFILT_JAILDESC (-15) /* attached to jail descriptors */
50#define EVFILT_SYSCOUNT 15
51
52#if defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L
53#define EV_SET(kevp_, a, b, c, d, e, f) do { \
54 *(kevp_) = (struct kevent){ \
55 .ident = (a), \
56 .filter = (b), \
57 .flags = (c), \
58 .fflags = (d), \
59 .data = (e), \
60 .udata = (f), \
61 .ext = {0}, \
62 }; \
63} while (0)
64#else /* Pre-C99 or not STDC (e.g., C++) */
65/*
66 * The definition of the local variable kevp could possibly conflict
67 * with a user-defined value passed in parameters a-f.
68 */
69#define EV_SET(kevp_, a, b, c, d, e, f) do { \
70 struct kevent *kevp = (kevp_); \
71 (kevp)->ident = (a); \
72 (kevp)->filter = (b); \
73 (kevp)->flags = (c); \
74 (kevp)->fflags = (d); \
75 (kevp)->data = (e); \
76 (kevp)->udata = (f); \
77 (kevp)->ext[0] = 0; \
78 (kevp)->ext[1] = 0; \
79 (kevp)->ext[2] = 0; \
80 (kevp)->ext[3] = 0; \
81} while (0)
82#endif
83
84struct kevent {
85 __uintptr_t ident; /* identifier for this event */
86 short filter; /* filter for event */
87 unsigned short flags; /* action flags for kqueue */
88 unsigned int fflags; /* filter flag value */
89 __int64_t data; /* filter data value */
90 void *udata; /* opaque user data identifier */
91 __uint64_t ext[4]; /* extensions */
92};
93
94#if defined(_WANT_FREEBSD11_KEVENT)
95/* Older structure used in FreeBSD 11.x and older. */
96struct freebsd11_kevent {
97 __uintptr_t ident; /* identifier for this event */
98 short filter; /* filter for event */
99 unsigned short flags;
100 unsigned int fflags;
101 __intptr_t data;
102 void *udata; /* opaque user data identifier */
103};
104#endif
105
106#if defined(_WANT_KEVENT32) || defined(_KERNEL)
107struct kevent32 {
108 __uint32_t ident; /* identifier for this event */
109 short filter; /* filter for event */
110 unsigned short flags;
111 unsigned int fflags;
112#ifndef __amd64__
113 __uint32_t pad0;
114#endif
115 __uint32_t data1, data2;
116 __uint32_t udata; /* opaque user data identifier */
117#ifndef __amd64__
118 __uint32_t pad1;
119#endif
120 __uint32_t ext64[8];
121};
122
123#ifdef _WANT_FREEBSD11_KEVENT
124struct freebsd11_kevent32 {
125 __uint32_t ident; /* identifier for this event */
126 short filter; /* filter for event */
127 unsigned short flags;
128 unsigned int fflags;
129 __int32_t data;
130 __uint32_t udata; /* opaque user data identifier */
131};
132#endif
133#endif
134
135/* actions */
136#define EV_ADD 0x0001 /* add event to kq (implies enable) */
137#define EV_DELETE 0x0002 /* delete event from kq */
138#define EV_ENABLE 0x0004 /* enable event */
139#define EV_DISABLE 0x0008 /* disable event (not reported) */
140#define EV_FORCEONESHOT 0x0100 /* enable _ONESHOT and force trigger */
141#define EV_KEEPUDATA 0x0200 /* do not update the udata field */
142
143/* flags */
144#define EV_ONESHOT 0x0010 /* only report one occurrence */
145#define EV_CLEAR 0x0020 /* clear event state after reporting */
146#define EV_RECEIPT 0x0040 /* force EV_ERROR on success, data=0 */
147#define EV_DISPATCH 0x0080 /* disable event after reporting */
148
149#define EV_SYSFLAGS 0xF000 /* reserved by system */
150#define EV_DROP 0x1000 /* note should be dropped */
151#define EV_FLAG1 0x2000 /* filter-specific flag */
152#define EV_FLAG2 0x4000 /* filter-specific flag */
153
154/* returned values */
155#define EV_EOF 0x8000 /* EOF detected */
156#define EV_ERROR 0x4000 /* error, data contains errno */
157
158 /*
159 * data/hint flags/masks for EVFILT_USER, shared with userspace
160 *
161 * On input, the top two bits of fflags specifies how the lower twenty four
162 * bits should be applied to the stored value of fflags.
163 *
164 * On output, the top two bits will always be set to NOTE_FFNOP and the
165 * remaining twenty four bits will contain the stored fflags value.
166 */
167#define NOTE_FFNOP 0x00000000 /* ignore input fflags */
168#define NOTE_FFAND 0x40000000 /* AND fflags */
169#define NOTE_FFOR 0x80000000 /* OR fflags */
170#define NOTE_FFCOPY 0xc0000000 /* copy fflags */
171#define NOTE_FFCTRLMASK 0xc0000000 /* masks for operations */
172#define NOTE_FFLAGSMASK 0x00ffffff
173
174#define NOTE_TRIGGER 0x01000000 /* Cause the event to be
175 triggered for output. */
176
177/*
178 * data/hint flags for EVFILT_{READ|WRITE}, shared with userspace
179 */
180#define NOTE_LOWAT 0x0001 /* low water mark */
181#define NOTE_FILE_POLL 0x0002 /* behave like poll() */
182
183/*
184 * data/hint flags for EVFILT_VNODE, shared with userspace
185 */
186#define NOTE_DELETE 0x0001 /* vnode was removed */
187#define NOTE_WRITE 0x0002 /* data contents changed */
188#define NOTE_EXTEND 0x0004 /* size increased */
189#define NOTE_ATTRIB 0x0008 /* attributes changed */
190#define NOTE_LINK 0x0010 /* link count changed */
191#define NOTE_RENAME 0x0020 /* vnode was renamed */
192#define NOTE_REVOKE 0x0040 /* vnode access was revoked */
193#define NOTE_OPEN 0x0080 /* vnode was opened */
194#define NOTE_CLOSE 0x0100 /* file closed, fd did not
195 allowed write */
196#define NOTE_CLOSE_WRITE 0x0200 /* file closed, fd did allowed
197 write */
198#define NOTE_READ 0x0400 /* file was read */
199
200/*
201 * data/hint flags for EVFILT_PROC and EVFILT_PROCDESC, shared with userspace
202 */
203#define NOTE_EXIT 0x80000000 /* process exited */
204#define NOTE_FORK 0x40000000 /* process forked */
205#define NOTE_EXEC 0x20000000 /* process exec'd */
206#define NOTE_PCTRLMASK 0xf0000000 /* mask for hint bits */
207#define NOTE_PDATAMASK 0x000fffff /* mask for pid */
208
209/* additional flags for EVFILT_PROC */
210#define NOTE_TRACK 0x00000001 /* follow across fork/create */
211#define NOTE_TRACKERR 0x00000002 /* could not track child */
212#define NOTE_CHILD 0x00000004 /* am a child process */
213
214/* data/hint flags for EVFILT_JAIL and EVFILT_JAILDESC */
215#define NOTE_JAIL_CHILD 0x80000000 /* child jail was created */
216#define NOTE_JAIL_SET 0x40000000 /* jail was modified */
217#define NOTE_JAIL_ATTACH 0x20000000 /* jail was attached to */
218#define NOTE_JAIL_REMOVE 0x10000000 /* jail was removed */
219#define NOTE_JAIL_MULTI 0x08000000 /* multiple child or attach */
220#define NOTE_JAIL_CTRLMASK 0xf0000000 /* mask for hint bits */
221
222/* additional flags for EVFILT_TIMER */
223#define NOTE_SECONDS 0x00000001 /* data is seconds */
224#define NOTE_MSECONDS 0x00000002 /* data is milliseconds */
225#define NOTE_USECONDS 0x00000004 /* data is microseconds */
226#define NOTE_NSECONDS 0x00000008 /* data is nanoseconds */
227#define NOTE_ABSTIME 0x00000010 /* timeout is absolute */
228
229/* Flags for kqueuex(2) */
230#define KQUEUE_CLOEXEC 0x00000001 /* close on exec */
231
232struct knote;
233SLIST_HEAD(klist, knote);
234struct kqueue;
235TAILQ_HEAD(kqlist, kqueue);
236struct knlist {
237 struct klist kl_list;
238 void (*kl_lock)(void *); /* lock function */
239 void (*kl_unlock)(void *);
240 void (*kl_assert_lock)(void *, int);
241 void *kl_lockarg; /* argument passed to lock functions */
242 int kl_autodestroy;
243};
244
245#ifdef _KERNEL
246
247/*
248 * Flags for knote call
249 */
250#define KNF_LISTLOCKED 0x0001 /* knlist is locked */
251#define KNF_NOKQLOCK 0x0002 /* do not keep KQ_LOCK */
252
253#define KNOTE(list, hint, flags) knote(list, hint, flags)
254#define KNOTE_LOCKED(list, hint) knote(list, hint, KNF_LISTLOCKED)
255#define KNOTE_UNLOCKED(list, hint) knote(list, hint, 0)
256
257#define KNLIST_EMPTY(list) SLIST_EMPTY(&(list)->kl_list)
258
259/*
260 * Flag indicating hint is a signal. Used by EVFILT_SIGNAL, and also
261 * shared by EVFILT_PROC (all knotes attached to p->p_klist)
262 */
263#define NOTE_SIGNAL 0x08000000
264
265/*
266 * Hint values for the optional f_touch event filter. If f_touch is not set
267 * to NULL and f_isfd is zero the f_touch filter will be called with the type
268 * argument set to EVENT_REGISTER during a kevent() system call. It is also
269 * called under the same conditions with the type argument set to EVENT_PROCESS
270 * when the event has been triggered.
271 */
272#define EVENT_REGISTER 1
273#define EVENT_PROCESS 2
274
275struct kinfo_knote;
276struct proc;
277
278struct filterops {
279 int f_isfd; /* true if ident == filedescriptor */
280 int (*f_attach)(struct knote *kn);
281 void (*f_detach)(struct knote *kn);
282 int (*f_event)(struct knote *kn, long hint);
283 void (*f_touch)(struct knote *kn, struct kevent *kev, u_long type);
284 int (*f_userdump)(struct proc *p, struct knote *kn,
285 struct kinfo_knote *kin);
286};
287
288/*
289 * An in-flux knote cannot be dropped from its kq while the kq is
290 * unlocked. If the KN_SCAN flag is not set, a thread can only set
291 * kn_influx when it is exclusive owner of the knote state, and can
292 * modify kn_status as if it had the KQ lock. KN_SCAN must not be set
293 * on a knote which is already in flux.
294 *
295 * kn_sfflags, kn_sdata, and kn_kevent are protected by the knlist lock.
296 */
297struct knote {
298 SLIST_ENTRY(knote) kn_link; /* for kq */
299 SLIST_ENTRY(knote) kn_selnext; /* for struct selinfo */
300 struct knlist *kn_knlist; /* f_attach populated */
301 TAILQ_ENTRY(knote) kn_tqe;
302 struct kqueue *kn_kq; /* which queue we are on */
303 struct kevent kn_kevent;
304 void *kn_hook;
305 int kn_hookid;
306 int kn_status; /* protected by kq lock */
307#define KN_ACTIVE 0x01 /* event has been triggered */
308#define KN_QUEUED 0x02 /* event is on queue */
309#define KN_DISABLED 0x04 /* event is disabled */
310#define KN_DETACHED 0x08 /* knote is detached */
311#define KN_MARKER 0x20 /* ignore this knote */
312#define KN_KQUEUE 0x40 /* this knote belongs to a kq */
313#define KN_SCAN 0x100 /* flux set in kqueue_scan() */
314 int kn_influx;
315 int kn_sfflags; /* saved filter flags */
316 int64_t kn_sdata; /* saved data field */
317 union {
318 struct file *p_fp; /* file data pointer */
319 struct proc *p_proc; /* proc pointer */
320 struct kaiocb *p_aio; /* AIO job pointer */
321 struct aioliojob *p_lio; /* LIO job pointer */
322 struct prison *p_prison; /* prison pointer */
323 void *p_v; /* generic other pointer */
324 } kn_ptr;
325 const struct filterops *kn_fop;
326
327#define kn_id kn_kevent.ident
328#define kn_filter kn_kevent.filter
329#define kn_flags kn_kevent.flags
330#define kn_fflags kn_kevent.fflags
331#define kn_data kn_kevent.data
332#define kn_fp kn_ptr.p_fp
333};
334struct kevent_copyops {
335 void *arg;
336 int (*k_copyout)(void *arg, struct kevent *kevp, int count);
337 int (*k_copyin)(void *arg, struct kevent *kevp, int count);
338 size_t kevent_size;
339};
340
341struct thread;
342struct proc;
343struct knlist;
344struct mtx;
345struct rwlock;
346
347void knote(struct knlist *list, long hint, int lockflags);
348void knote_fork(struct knlist *list, int pid);
349struct knlist *knlist_alloc(struct mtx *lock);
350void knlist_detach(struct knlist *knl);
351void knlist_add(struct knlist *knl, struct knote *kn, int islocked);
352void knlist_remove(struct knlist *knl, struct knote *kn, int islocked);
353int knlist_empty(struct knlist *knl);
354void knlist_init(struct knlist *knl, void *lock, void (*kl_lock)(void *),
355 void (*kl_unlock)(void *), void (*kl_assert_lock)(void *, int));
356void knlist_init_mtx(struct knlist *knl, struct mtx *lock);
357void knlist_destroy(struct knlist *knl);
358void knlist_cleardel(struct knlist *knl, struct thread *td,
359 int islocked, int killkn);
360#define knlist_clear(knl, islocked) \
361 knlist_cleardel((knl), NULL, (islocked), 0)
362#define knlist_delete(knl, td, islocked) \
363 knlist_cleardel((knl), (td), (islocked), 1)
364void knote_fdclose(struct thread *p, int fd);
365int kqfd_register(int fd, struct kevent *kev, struct thread *p,
366 int mflag);
367int kqueue_add_filteropts(int filt, const struct filterops *filtops);
368int kqueue_del_filteropts(int filt);
369void kqueue_drain_schedtask(void);
370
371#else /* !_KERNEL */
372
373#include <sys/cdefs.h>
374struct timespec;
375
376__BEGIN_DECLS
377int kqueue(void);
378int kqueuex(unsigned flags);
379int kqueue1(int flags);
380int kevent(int kq, const struct kevent *changelist, int nchanges,
381 struct kevent *eventlist, int nevents,
382 const struct timespec *timeout);
383__END_DECLS
384
385#endif /* !_KERNEL */
386
387#endif /* !_SYS_EVENT_H_ */