sys/sys/event.h

   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 #define EVFILT_FS               (-10)   /* filesystem events */
  50
  51 #define EVFILT_MARKER           0xF     /* placemarker for tailq */
  52
  53 #define EVFILT_SYSCOUNT         10
  54
  55 #define EV_SET(kevp_, a, b, c, d, e, f) do {    \
  56         struct kevent *kevp = (kevp_);          \
  57         (kevp)->ident = (a);                    \
  58         (kevp)->filter = (b);                   \
  59         (kevp)->flags = (c);                    \
  60         (kevp)->fflags = (d);                   \
  61         (kevp)->data = (e);                     \
  62         (kevp)->udata = (f);                    \
  63 } while(0)
  64
  65 struct kevent {
  66         uintptr_t       ident;          /* identifier for this event */
  67         short           filter;         /* filter for event */
  68         u_short         flags;
  69         u_int           fflags;
  70         intptr_t        data;
  71         void            *udata;         /* opaque user data identifier */
  72 };
  73
  74 /* actions */
  75 #define EV_ADD          0x0001          /* add event to kq (implies enable) */
  76 #define EV_DELETE       0x0002          /* delete event from kq */
  77 #define EV_ENABLE       0x0004          /* enable event */
  78 #define EV_DISABLE      0x0008          /* disable event (not reported) */
  79
  80 /* flags */
  81 #define EV_ONESHOT      0x0010          /* only report one occurrence */
  82 #define EV_CLEAR        0x0020          /* clear event state after reporting */
  83 #define EV_RECEIPT      0x0040          /* force EV_ERROR on success, data=0 */
  84 #define EV_DISPATCH     0x0080          /* disable event after reporting */
  85
  86 #define EV_SYSFLAGS     0xF000          /* reserved by system */
  87 #define EV_FLAG1        0x2000          /* filter-specific flag */
  88
  89 /* returned values */
  90 #define EV_EOF          0x8000          /* EOF detected */
  91 #define EV_ERROR        0x4000          /* error, data contains errno */
  92 #define EV_NODATA       0x1000          /* EOF and no more data */
  93
  94 /*
  95  * EVFILT_USER
  96  */
  97  /*
  98   * data/hint flags/masks for EVFILT_USER, shared with userspace
  99   *
 100   * On input, the top two bits of fflags specifies how the lower twenty four
 101   * bits should be applied to the stored value of fflags.
 102   *
 103   * On output, the top two bits will always be set to NOTE_FFNOP and the
 104   * remaining twenty four bits will contain the stored fflags value.
 105   */
 106 #define NOTE_FFNOP      0x00000000      /* ignore input fflags */
 107 #define NOTE_FFAND      0x40000000      /* AND fflags */
 108 #define NOTE_FFOR       0x80000000      /* OR fflags */
 109 #define NOTE_FFCOPY     0xc0000000      /* copy fflags */
 110 #define NOTE_FFCTRLMASK 0xc0000000      /* masks for operations */
 111 #define NOTE_FFLAGSMASK 0x00ffffff
 112
 113 #define NOTE_TRIGGER    0x01000000      /* trigger for output */
 114
 115 /*
 116  * data/hint flags for EVFILT_{READ|WRITE}, shared with userspace
 117  */
 118 #define NOTE_LOWAT      0x0001                  /* low water mark */
 119
 120 /*
 121  * data/hint flags for EVFILT_EXCEPT, shared with userspace and with
 122  * EVFILT_{READ|WRITE}
 123  */
 124 #define NOTE_OOB        0x0002                  /* OOB data on a socket */
 125
 126 /*
 127  * data/hint flags for EVFILT_VNODE, shared with userspace
 128  */
 129 #define NOTE_DELETE     0x0001                  /* vnode was removed */
 130 #define NOTE_WRITE      0x0002                  /* data contents changed */
 131 #define NOTE_EXTEND     0x0004                  /* size increased */
 132 #define NOTE_ATTRIB     0x0008                  /* attributes changed */
 133 #define NOTE_LINK       0x0010                  /* link count changed */
 134 #define NOTE_RENAME     0x0020                  /* vnode was renamed */
 135 #define NOTE_REVOKE     0x0040                  /* vnode access was revoked */
 136
 137 /*
 138  * data/hint flags for EVFILT_PROC, shared with userspace
 139  */
 140 #define NOTE_EXIT       0x80000000              /* process exited */
 141 #define NOTE_FORK       0x40000000              /* process forked */
 142 #define NOTE_EXEC       0x20000000              /* process exec'd */
 143 #define NOTE_PCTRLMASK  0xf0000000              /* mask for hint bits */
 144 #define NOTE_PDATAMASK  0x000fffff              /* mask for pid */
 145
 146 /* additional flags for EVFILT_PROC */
 147 #define NOTE_TRACK      0x00000001              /* follow across forks */
 148 #define NOTE_TRACKERR   0x00000002              /* could not track child */
 149 #define NOTE_CHILD      0x00000004              /* am a child process */
 150
 151 #if defined(_KERNEL) || defined(_KERNEL_STRUCTURES)
 152
 153 struct knote;
 154 SLIST_HEAD(klist, knote);
 155
 156 /*
 157  * Used to maintain information about processes that wish to be
 158  * notified when I/O becomes possible.
 159  */
 160 struct kqinfo {
 161         struct  klist ki_note;          /* kernel note list */
 162 };
 163
 164 #endif
 165
 166 #ifdef _KERNEL
 167
 168 #ifdef MALLOC_DECLARE
 169 MALLOC_DECLARE(M_KQUEUE);
 170 #endif
 171
 172 #define KNOTE(list, hint)       if (!SLIST_EMPTY((list))) knote(list, hint)
 173
 174 /*
 175  * Flag indicating hint is a signal.  Used by EVFILT_SIGNAL, and also
 176  * shared by EVFILT_PROC  (all knotes attached to p->p_klist)
 177  *
 178  * NOTE_OLDAPI is used to signal that standard filters are being called
 179  * from the select/poll wrapper.
 180  */
 181 #define NOTE_SIGNAL     0x08000000
 182 #define NOTE_OLDAPI     0x04000000      /* select/poll note */
 183
 184 #define FILTEROP_ISFD   0x0001          /* if ident == filedescriptor */
 185 #define FILTEROP_MPSAFE 0x0002
 186
 187 struct filterops {
 188         u_short f_flags;
 189
 190         /* f_attach returns 0 on success or valid error code on failure */
 191         int     (*f_attach)     (struct knote *kn);
 192         void    (*f_detach)     (struct knote *kn);
 193
 194         /* f_event returns boolean truth */
 195         int     (*f_event)      (struct knote *kn, long hint);
 196 };
 197
 198 struct knote {
 199         SLIST_ENTRY(knote)      kn_link;        /* for fd */
 200         TAILQ_ENTRY(knote)      kn_kqlink;      /* for kq_knlist */
 201         SLIST_ENTRY(knote)      kn_next;        /* for struct kqinfo */
 202         TAILQ_ENTRY(knote)      kn_tqe;         /* for kq_knpend */
 203         struct                  kqueue *kn_kq;  /* which queue we are on */
 204         struct                  kevent kn_kevent;
 205         int                     kn_status;
 206         int                     kn_sfflags;     /* saved filter flags */
 207         intptr_t                kn_sdata;       /* saved data field */
 208         union {
 209                 struct          file *p_fp;     /* file data pointer */
 210                 struct          proc *p_proc;   /* proc pointer */
 211                 int             hookid;
 212         } kn_ptr;
 213         struct                  filterops *kn_fop;
 214         caddr_t                 kn_hook;
 215 };
 216
 217 #define KN_ACTIVE       0x0001                  /* event has been triggered */
 218 #define KN_QUEUED       0x0002                  /* event is on queue */
 219 #define KN_DISABLED     0x0004                  /* event is disabled */
 220 #define KN_DETACHED     0x0008                  /* knote is detached */
 221 #define KN_REPROCESS    0x0010                  /* force reprocessing race */
 222 #define KN_DELETING     0x0020                  /* deletion in progress */
 223 #define KN_PROCESSING   0x0040                  /* event processing in prog */
 224 #define KN_WAITING      0x0080                  /* waiting on processing */
 225
 226 #define kn_id           kn_kevent.ident
 227 #define kn_filter       kn_kevent.filter
 228 #define kn_flags        kn_kevent.flags
 229 #define kn_fflags       kn_kevent.fflags
 230 #define kn_data         kn_kevent.data
 231 #define kn_fp           kn_ptr.p_fp
 232
 233 struct proc;
 234 struct thread;
 235 struct filedesc;
 236 struct kevent_args;
 237
 238 #define KEVENT_TIMEOUT_PRECISE  0x01
 239
 240 typedef int     (*k_copyout_fn)(void *arg, struct kevent *kevp, int count,
 241     int *res);
 242 typedef int     (*k_copyin_fn)(void *arg, struct kevent *kevp, int max,
 243     int *events);
 244 int kern_kevent(struct kqueue *kq, int nevents, int *res, void *uap,
 245     k_copyin_fn kevent_copyin, k_copyout_fn kevent_copyout,
 246     struct timespec *tsp, int flags);
 247
 248 extern void     knote(struct klist *list, long hint);
 249 extern void     knote_insert(struct klist *klist, struct knote *kn);
 250 extern void     knote_remove(struct klist *klist, struct knote *kn);
 251 extern void     knote_assume_knotes(struct kqinfo *, struct kqinfo *,
 252                     struct filterops *, void *);
 253 extern void     knote_fdclose(struct file *fp, struct filedesc *fdp, int fd);
 254 extern void     kqueue_init(struct kqueue *kq, struct filedesc *fdp);
 255 extern void     kqueue_terminate(struct kqueue *kq);
 256 extern int      kqueue_register(struct kqueue *kq, struct kevent *kev);
 257
 258 extern struct klist fs_klist;   /* EVFILT_FS */
 259
 260 #endif  /* _KERNEL */
 261
 262 #if !defined(_KERNEL) || defined(_KERNEL_VIRTUAL)
 263
 264 #include <sys/cdefs.h>
 265 struct timespec;
 266
 267 __BEGIN_DECLS
 268 int     kqueue (void);
 269 int     kevent (int, const struct kevent *, int, struct kevent *,
 270                 int, const struct timespec *);
 271 __END_DECLS
 272 #endif /* !_KERNEL */
 273
 274 #endif /* !_SYS_EVENT_H_ */