RTEMS  5.1
event.h
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
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: head/sys/sys/event.h 336457 2018-07-18 13:04:03Z dab $
29  */
30 
31 #ifndef _SYS_EVENT_H_
32 #define _SYS_EVENT_H_
33 
34 #include <sys/_types.h>
35 #include <sys/queue.h>
36 
37 #define EVFILT_READ (-1)
38 #define EVFILT_WRITE (-2)
39 #define EVFILT_AIO (-3) /* attached to aio requests */
40 #define EVFILT_VNODE (-4) /* attached to vnodes */
41 #define EVFILT_PROC (-5) /* attached to struct proc */
42 #define EVFILT_SIGNAL (-6) /* attached to struct proc */
43 #define EVFILT_TIMER (-7) /* timers */
44 #define EVFILT_PROCDESC (-8) /* attached to process descriptors */
45 #define EVFILT_FS (-9) /* filesystem events */
46 #define EVFILT_LIO (-10) /* attached to lio requests */
47 #define EVFILT_USER (-11) /* User events */
48 #define EVFILT_SENDFILE (-12) /* attached to sendfile requests */
49 #define EVFILT_EMPTY (-13) /* empty send socket buf */
50 #define EVFILT_SYSCOUNT 13
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 /* The definition of the local variable kevp could possibly conflict
66  * with a user-defined value passed in parameters a-f.
67  */
68 #define EV_SET(kevp_, a, b, c, d, e, f) do { \
69  struct kevent *kevp = (kevp_); \
70  (kevp)->ident = (a); \
71  (kevp)->filter = (b); \
72  (kevp)->flags = (c); \
73  (kevp)->fflags = (d); \
74  (kevp)->data = (e); \
75  (kevp)->udata = (f); \
76  (kevp)->ext[0] = 0; \
77  (kevp)->ext[1] = 0; \
78  (kevp)->ext[2] = 0; \
79  (kevp)->ext[3] = 0; \
80 } while(0)
81 #endif
82 
83 struct kevent {
84  __uintptr_t ident; /* identifier for this event */
85  short filter; /* filter for event */
86  unsigned short flags; /* action flags for kqueue */
87  unsigned int fflags; /* filter flag value */
88  __int64_t data; /* filter data value */
89  void *udata; /* opaque user data identifier */
90  __uint64_t ext[4]; /* extensions */
91 };
92 
93 #if defined(_WANT_FREEBSD11_KEVENT)
94 /* Older structure used in FreeBSD 11.x and older. */
95 struct kevent_freebsd11 {
96  __uintptr_t ident; /* identifier for this event */
97  short filter; /* filter for event */
98  unsigned short flags;
99  unsigned int fflags;
100  __intptr_t data;
101  void *udata; /* opaque user data identifier */
102 };
103 #endif
104 
105 #if defined(_WANT_KEVENT32) || (defined(_KERNEL) && defined(__LP64__))
106 struct kevent32 {
107  uint32_t ident; /* identifier for this event */
108  short filter; /* filter for event */
109  u_short flags;
110  u_int fflags;
111 #ifndef __amd64__
112  uint32_t pad0;
113 #endif
114  int32_t data1, data2;
115  uint32_t udata; /* opaque user data identifier */
116 #ifndef __amd64__
117  uint32_t pad1;
118 #endif
119  uint32_t ext64[8];
120 };
121 
122 #ifdef _WANT_FREEBSD11_KEVENT
123 struct kevent32_freebsd11 {
124  u_int32_t ident; /* identifier for this event */
125  short filter; /* filter for event */
126  u_short flags;
127  u_int fflags;
128  int32_t data;
129  u_int32_t udata; /* opaque user data identifier */
130 };
131 #endif
132 #endif
133 
134 /* actions */
135 #define EV_ADD 0x0001 /* add event to kq (implies enable) */
136 #define EV_DELETE 0x0002 /* delete event from kq */
137 #define EV_ENABLE 0x0004 /* enable event */
138 #define EV_DISABLE 0x0008 /* disable event (not reported) */
139 #define EV_FORCEONESHOT 0x0100 /* enable _ONESHOT and force trigger */
140 
141 /* flags */
142 #define EV_ONESHOT 0x0010 /* only report one occurrence */
143 #define EV_CLEAR 0x0020 /* clear event state after reporting */
144 #define EV_RECEIPT 0x0040 /* force EV_ERROR on success, data=0 */
145 #define EV_DISPATCH 0x0080 /* disable event after reporting */
146 
147 #define EV_SYSFLAGS 0xF000 /* reserved by system */
148 #define EV_DROP 0x1000 /* note should be dropped */
149 #define EV_FLAG1 0x2000 /* filter-specific flag */
150 #define EV_FLAG2 0x4000 /* filter-specific flag */
151 
152 /* returned values */
153 #define EV_EOF 0x8000 /* EOF detected */
154 #define EV_ERROR 0x4000 /* error, data contains errno */
155 
156  /*
157  * data/hint flags/masks for EVFILT_USER, shared with userspace
158  *
159  * On input, the top two bits of fflags specifies how the lower twenty four
160  * bits should be applied to the stored value of fflags.
161  *
162  * On output, the top two bits will always be set to NOTE_FFNOP and the
163  * remaining twenty four bits will contain the stored fflags value.
164  */
165 #define NOTE_FFNOP 0x00000000 /* ignore input fflags */
166 #define NOTE_FFAND 0x40000000 /* AND fflags */
167 #define NOTE_FFOR 0x80000000 /* OR fflags */
168 #define NOTE_FFCOPY 0xc0000000 /* copy fflags */
169 #define NOTE_FFCTRLMASK 0xc0000000 /* masks for operations */
170 #define NOTE_FFLAGSMASK 0x00ffffff
171 
172 #define NOTE_TRIGGER 0x01000000 /* Cause the event to be
173  triggered for output. */
174 
175 /*
176  * data/hint flags for EVFILT_{READ|WRITE}, shared with userspace
177  */
178 #define NOTE_LOWAT 0x0001 /* low water mark */
179 #define NOTE_FILE_POLL 0x0002 /* behave like poll() */
180 
181 /*
182  * data/hint flags for EVFILT_VNODE, shared with userspace
183  */
184 #define NOTE_DELETE 0x0001 /* vnode was removed */
185 #define NOTE_WRITE 0x0002 /* data contents changed */
186 #define NOTE_EXTEND 0x0004 /* size increased */
187 #define NOTE_ATTRIB 0x0008 /* attributes changed */
188 #define NOTE_LINK 0x0010 /* link count changed */
189 #define NOTE_RENAME 0x0020 /* vnode was renamed */
190 #define NOTE_REVOKE 0x0040 /* vnode access was revoked */
191 #define NOTE_OPEN 0x0080 /* vnode was opened */
192 #define NOTE_CLOSE 0x0100 /* file closed, fd did not
193  allowed write */
194 #define NOTE_CLOSE_WRITE 0x0200 /* file closed, fd did allowed
195  write */
196 #define NOTE_READ 0x0400 /* file was read */
197 
198 /*
199  * data/hint flags for EVFILT_PROC and EVFILT_PROCDESC, shared with userspace
200  */
201 #define NOTE_EXIT 0x80000000 /* process exited */
202 #define NOTE_FORK 0x40000000 /* process forked */
203 #define NOTE_EXEC 0x20000000 /* process exec'd */
204 #define NOTE_PCTRLMASK 0xf0000000 /* mask for hint bits */
205 #define NOTE_PDATAMASK 0x000fffff /* mask for pid */
206 
207 /* additional flags for EVFILT_PROC */
208 #define NOTE_TRACK 0x00000001 /* follow across forks */
209 #define NOTE_TRACKERR 0x00000002 /* could not track child */
210 #define NOTE_CHILD 0x00000004 /* am a child process */
211 
212 /* additional flags for EVFILT_TIMER */
213 #define NOTE_SECONDS 0x00000001 /* data is seconds */
214 #define NOTE_MSECONDS 0x00000002 /* data is milliseconds */
215 #define NOTE_USECONDS 0x00000004 /* data is microseconds */
216 #define NOTE_NSECONDS 0x00000008 /* data is nanoseconds */
217 #define NOTE_ABSTIME 0x00000010 /* timeout is absolute */
218 
219 struct knote;
220 SLIST_HEAD(klist, knote);
221 struct kqueue;
222 TAILQ_HEAD(kqlist, kqueue);
223 struct knlist {
224  struct klist kl_list;
225  void (*kl_lock)(void *); /* lock function */
226  void (*kl_unlock)(void *);
227  void (*kl_assert_locked)(void *);
228  void (*kl_assert_unlocked)(void *);
229  void *kl_lockarg; /* argument passed to lock functions */
230  int kl_autodestroy;
231 };
232 
233 
234 #ifdef _KERNEL
235 
236 /*
237  * Flags for knote call
238  */
239 #define KNF_LISTLOCKED 0x0001 /* knlist is locked */
240 #define KNF_NOKQLOCK 0x0002 /* do not keep KQ_LOCK */
241 
242 #define KNOTE(list, hint, flags) knote(list, hint, flags)
243 #define KNOTE_LOCKED(list, hint) knote(list, hint, KNF_LISTLOCKED)
244 #define KNOTE_UNLOCKED(list, hint) knote(list, hint, 0)
245 
246 #define KNLIST_EMPTY(list) SLIST_EMPTY(&(list)->kl_list)
247 
248 /*
249  * Flag indicating hint is a signal. Used by EVFILT_SIGNAL, and also
250  * shared by EVFILT_PROC (all knotes attached to p->p_klist)
251  */
252 #define NOTE_SIGNAL 0x08000000
253 
254 /*
255  * Hint values for the optional f_touch event filter. If f_touch is not set
256  * to NULL and f_isfd is zero the f_touch filter will be called with the type
257  * argument set to EVENT_REGISTER during a kevent() system call. It is also
258  * called under the same conditions with the type argument set to EVENT_PROCESS
259  * when the event has been triggered.
260  */
261 #define EVENT_REGISTER 1
262 #define EVENT_PROCESS 2
263 
264 struct filterops {
265  int f_isfd; /* true if ident == filedescriptor */
266  int (*f_attach)(struct knote *kn);
267  void (*f_detach)(struct knote *kn);
268  int (*f_event)(struct knote *kn, long hint);
269  void (*f_touch)(struct knote *kn, struct kevent *kev, u_long type);
270 };
271 
272 /*
273  * An in-flux knote cannot be dropped from its kq while the kq is
274  * unlocked. If the KN_SCAN flag is not set, a thread can only set
275  * kn_influx when it is exclusive owner of the knote state, and can
276  * modify kn_status as if it had the KQ lock. KN_SCAN must not be set
277  * on a knote which is already in flux.
278  *
279  * kn_sfflags, kn_sdata, and kn_kevent are protected by the knlist lock.
280  */
281 struct knote {
282  SLIST_ENTRY(knote) kn_link; /* for kq */
283  SLIST_ENTRY(knote) kn_selnext; /* for struct selinfo */
284  struct knlist *kn_knlist; /* f_attach populated */
285  TAILQ_ENTRY(knote) kn_tqe;
286  struct kqueue *kn_kq; /* which queue we are on */
287  struct kevent kn_kevent;
288  void *kn_hook;
289  int kn_hookid;
290  int kn_status; /* protected by kq lock */
291 #define KN_ACTIVE 0x01 /* event has been triggered */
292 #define KN_QUEUED 0x02 /* event is on queue */
293 #define KN_DISABLED 0x04 /* event is disabled */
294 #define KN_DETACHED 0x08 /* knote is detached */
295 #define KN_MARKER 0x20 /* ignore this knote */
296 #define KN_KQUEUE 0x40 /* this knote belongs to a kq */
297 #define KN_HASKQLOCK 0x80 /* for _inevent */
298 #define KN_SCAN 0x100 /* flux set in kqueue_scan() */
299  int kn_influx;
300  int kn_sfflags; /* saved filter flags */
301  int64_t kn_sdata; /* saved data field */
302  union {
303  struct file *p_fp; /* file data pointer */
304  struct proc *p_proc; /* proc pointer */
305  struct kaiocb *p_aio; /* AIO job pointer */
306  struct aioliojob *p_lio; /* LIO job pointer */
307  void *p_v; /* generic other pointer */
308  } kn_ptr;
309  struct filterops *kn_fop;
310 
311 #define kn_id kn_kevent.ident
312 #define kn_filter kn_kevent.filter
313 #define kn_flags kn_kevent.flags
314 #define kn_fflags kn_kevent.fflags
315 #define kn_data kn_kevent.data
316 #define kn_fp kn_ptr.p_fp
317 };
318 struct kevent_copyops {
319  void *arg;
320  int (*k_copyout)(void *arg, struct kevent *kevp, int count);
321  int (*k_copyin)(void *arg, struct kevent *kevp, int count);
322  size_t kevent_size;
323 };
324 
325 struct thread;
326 struct proc;
327 struct knlist;
328 struct mtx;
329 struct rwlock;
330 
331 void knote(struct knlist *list, long hint, int lockflags);
332 void knote_fork(struct knlist *list, int pid);
333 struct knlist *knlist_alloc(struct mtx *lock);
334 void knlist_detach(struct knlist *knl);
335 void knlist_add(struct knlist *knl, struct knote *kn, int islocked);
336 void knlist_remove(struct knlist *knl, struct knote *kn, int islocked);
337 int knlist_empty(struct knlist *knl);
338 void knlist_init(struct knlist *knl, void *lock, void (*kl_lock)(void *),
339  void (*kl_unlock)(void *), void (*kl_assert_locked)(void *),
340  void (*kl_assert_unlocked)(void *));
341 void knlist_init_mtx(struct knlist *knl, struct mtx *lock);
342 void knlist_init_rw_reader(struct knlist *knl, struct rwlock *lock);
343 void knlist_destroy(struct knlist *knl);
344 void knlist_cleardel(struct knlist *knl, struct thread *td,
345  int islocked, int killkn);
346 #define knlist_clear(knl, islocked) \
347  knlist_cleardel((knl), NULL, (islocked), 0)
348 #define knlist_delete(knl, td, islocked) \
349  knlist_cleardel((knl), (td), (islocked), 1)
350 void knote_fdclose(struct thread *p, int fd);
351 int kqfd_register(int fd, struct kevent *kev, struct thread *p,
352  int waitok);
353 int kqueue_add_filteropts(int filt, struct filterops *filtops);
354 int kqueue_del_filteropts(int filt);
355 
356 #else /* !_KERNEL */
357 
358 #include <sys/cdefs.h>
359 struct timespec;
360 
361 __BEGIN_DECLS
362 int kqueue(void);
363 int kevent(int kq, const struct kevent *changelist, int nchanges,
364  struct kevent *eventlist, int nevents,
365  const struct timespec *timeout);
366 __END_DECLS
367 
368 #endif /* !_KERNEL */
369 
370 #endif /* !_SYS_EVENT_H_ */
p
unsigned p
Definition: tte.h:90
mtx
Definition: if_fxpvar.h:78
kevent
Definition: event.h:83
file
Definition: mongoose.c:442
knlist
Definition: event.h:223
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