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event.h (17873B) - Raw


      1 /*
      2  * Copyright (c) 2003-2021 Apple Inc. All rights reserved.
      3  *
      4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
      5  *
      6  * This file contains Original Code and/or Modifications of Original Code
      7  * as defined in and that are subject to the Apple Public Source License
      8  * Version 2.0 (the 'License'). You may not use this file except in
      9  * compliance with the License. The rights granted to you under the License
     10  * may not be used to create, or enable the creation or redistribution of,
     11  * unlawful or unlicensed copies of an Apple operating system, or to
     12  * circumvent, violate, or enable the circumvention or violation of, any
     13  * terms of an Apple operating system software license agreement.
     14  *
     15  * Please obtain a copy of the License at
     16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
     17  *
     18  * The Original Code and all software distributed under the License are
     19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
     20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
     21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
     22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
     23  * Please see the License for the specific language governing rights and
     24  * limitations under the License.
     25  *
     26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
     27  */
     28 /*-
     29  * Copyright (c) 1999,2000,2001 Jonathan Lemon <jlemon@FreeBSD.org>
     30  * All rights reserved.
     31  *
     32  * Redistribution and use in source and binary forms, with or without
     33  * modification, are permitted provided that the following conditions
     34  * are met:
     35  * 1. Redistributions of source code must retain the above copyright
     36  *    notice, this list of conditions and the following disclaimer.
     37  * 2. Redistributions in binary form must reproduce the above copyright
     38  *    notice, this list of conditions and the following disclaimer in the
     39  *    documentation and/or other materials provided with the distribution.
     40  *
     41  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
     42  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     43  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     44  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
     45  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     46  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     47  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     48  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     49  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     50  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     51  * SUCH DAMAGE.
     52  *
     53  *	$FreeBSD: src/sys/sys/event.h,v 1.5.2.5 2001/12/14 19:21:22 jlemon Exp $
     54  */
     55 
     56 #ifndef _SYS_EVENT_H_
     57 #define _SYS_EVENT_H_
     58 
     59 #include <machine/types.h>
     60 #include <sys/cdefs.h>
     61 #include <sys/queue.h>
     62 #include <stdint.h>
     63 #include <sys/types.h>
     64 
     65 /*
     66  * Filter types
     67  */
     68 #define EVFILT_READ             (-1)
     69 #define EVFILT_WRITE            (-2)
     70 #define EVFILT_AIO              (-3)    /* attached to aio requests */
     71 #define EVFILT_VNODE            (-4)    /* attached to vnodes */
     72 #define EVFILT_PROC             (-5)    /* attached to struct proc */
     73 #define EVFILT_SIGNAL           (-6)    /* attached to struct proc */
     74 #define EVFILT_TIMER            (-7)    /* timers */
     75 #define EVFILT_MACHPORT         (-8)    /* Mach portsets */
     76 #define EVFILT_FS               (-9)    /* Filesystem events */
     77 #define EVFILT_USER             (-10)   /* User events */
     78 #define EVFILT_VM               (-12)   /* Virtual memory events */
     79 #define EVFILT_EXCEPT           (-15)   /* Exception events */
     80 
     81 #define EVFILT_SYSCOUNT         18
     82 #define EVFILT_THREADMARKER     EVFILT_SYSCOUNT /* Internal use only */
     83 
     84 #pragma pack(4)
     85 
     86 struct kevent {
     87 	uintptr_t       ident;  /* identifier for this event */
     88 	int16_t         filter; /* filter for event */
     89 	uint16_t        flags;  /* general flags */
     90 	uint32_t        fflags; /* filter-specific flags */
     91 	intptr_t        data;   /* filter-specific data */
     92 	void            *udata; /* opaque user data identifier */
     93 };
     94 
     95 #pragma pack()
     96 
     97 struct kevent64_s {
     98 	uint64_t        ident;          /* identifier for this event */
     99 	int16_t         filter;         /* filter for event */
    100 	uint16_t        flags;          /* general flags */
    101 	uint32_t        fflags;         /* filter-specific flags */
    102 	int64_t         data;           /* filter-specific data */
    103 	uint64_t        udata;          /* opaque user data identifier */
    104 	uint64_t        ext[2];         /* filter-specific extensions */
    105 };
    106 
    107 #define EV_SET(kevp, a, b, c, d, e, f) do {     \
    108 	struct kevent *__kevp__ = (kevp);       \
    109 	__kevp__->ident = (a);                  \
    110 	__kevp__->filter = (b);                 \
    111 	__kevp__->flags = (c);                  \
    112 	__kevp__->fflags = (d);                 \
    113 	__kevp__->data = (e);                   \
    114 	__kevp__->udata = (f);                  \
    115 } while(0)
    116 
    117 #define EV_SET64(kevp, a, b, c, d, e, f, g, h) do {     \
    118 	struct kevent64_s *__kevp__ = (kevp);           \
    119 	__kevp__->ident = (a);                          \
    120 	__kevp__->filter = (b);                         \
    121 	__kevp__->flags = (c);                          \
    122 	__kevp__->fflags = (d);                         \
    123 	__kevp__->data = (e);                           \
    124 	__kevp__->udata = (f);                          \
    125 	__kevp__->ext[0] = (g);                         \
    126 	__kevp__->ext[1] = (h);                         \
    127 } while(0)
    128 
    129 
    130 /* kevent system call flags */
    131 #define KEVENT_FLAG_NONE                         0x000000       /* no flag value */
    132 #define KEVENT_FLAG_IMMEDIATE                    0x000001       /* immediate timeout */
    133 #define KEVENT_FLAG_ERROR_EVENTS                 0x000002       /* output events only include change errors */
    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 
    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 immediate event output */
    145                                         /* ... with or without EV_ERROR */
    146                                         /* ... use KEVENT_FLAG_ERROR_EVENTS */
    147                                         /*     on syscalls supporting flags */
    148 
    149 #define EV_DISPATCH         0x0080      /* disable event after reporting */
    150 #define EV_UDATA_SPECIFIC   0x0100      /* unique kevent per udata value */
    151 
    152 #define EV_DISPATCH2        (EV_DISPATCH | EV_UDATA_SPECIFIC)
    153 /* ... in combination with EV_DELETE */
    154 /* will defer delete until udata-specific */
    155 /* event enabled. EINPROGRESS will be */
    156 /* returned to indicate the deferral */
    157 
    158 #define EV_VANISHED         0x0200      /* report that source has vanished  */
    159                                         /* ... only valid with EV_DISPATCH2 */
    160 
    161 #define EV_SYSFLAGS         0xF000      /* reserved by system */
    162 #define EV_FLAG0            0x1000      /* filter-specific flag */
    163 #define EV_FLAG1            0x2000      /* filter-specific flag */
    164 
    165 /* returned values */
    166 #define EV_EOF              0x8000      /* EOF detected */
    167 #define EV_ERROR            0x4000      /* error, data contains errno */
    168 
    169 /*
    170  * Filter specific flags for EVFILT_READ
    171  *
    172  * The default behavior for EVFILT_READ is to make the "read" determination
    173  * relative to the current file descriptor read pointer.
    174  *
    175  * The EV_POLL flag indicates the determination should be made via poll(2)
    176  * semantics. These semantics dictate always returning true for regular files,
    177  * regardless of the amount of unread data in the file.
    178  *
    179  * On input, EV_OOBAND specifies that filter should actively return in the
    180  * presence of OOB on the descriptor. It implies that filter will return
    181  * if there is OOB data available to read OR when any other condition
    182  * for the read are met (for example number of bytes regular data becomes >=
    183  * low-watermark).
    184  * If EV_OOBAND is not set on input, it implies that the filter should not actively
    185  * return for out of band data on the descriptor. The filter will then only return
    186  * when some other condition for read is met (ex: when number of regular data bytes
    187  * >=low-watermark OR when socket can't receive more data (SS_CANTRCVMORE)).
    188  *
    189  * On output, EV_OOBAND indicates the presence of OOB data on the descriptor.
    190  * If it was not specified as an input parameter, then the data count is the
    191  * number of bytes before the current OOB marker, else data count is the number
    192  * of bytes beyond OOB marker.
    193  */
    194 #define EV_POLL         EV_FLAG0
    195 #define EV_OOBAND       EV_FLAG1
    196 
    197 /*
    198  * data/hint fflags for EVFILT_USER, shared with userspace
    199  */
    200 
    201 /*
    202  * On input, NOTE_TRIGGER causes the event to be triggered for output.
    203  */
    204 #define NOTE_TRIGGER    0x01000000
    205 
    206 /*
    207  * On input, the top two bits of fflags specifies how the lower twenty four
    208  * bits should be applied to the stored value of fflags.
    209  *
    210  * On output, the top two bits will always be set to NOTE_FFNOP and the
    211  * remaining twenty four bits will contain the stored fflags value.
    212  */
    213 #define NOTE_FFNOP      0x00000000              /* ignore input fflags */
    214 #define NOTE_FFAND      0x40000000              /* and fflags */
    215 #define NOTE_FFOR       0x80000000              /* or fflags */
    216 #define NOTE_FFCOPY     0xc0000000              /* copy fflags */
    217 #define NOTE_FFCTRLMASK 0xc0000000              /* mask for operations */
    218 #define NOTE_FFLAGSMASK 0x00ffffff
    219 
    220 /*
    221  * data/hint fflags for EVFILT_{READ|WRITE}, shared with userspace
    222  *
    223  * The default behavior for EVFILT_READ is to make the determination
    224  * realtive to the current file descriptor read pointer.
    225  */
    226 #define NOTE_LOWAT      0x00000001              /* low water mark */
    227 
    228 /* data/hint flags for EVFILT_EXCEPT, shared with userspace */
    229 #define NOTE_OOB        0x00000002              /* OOB data */
    230 
    231 /*
    232  * data/hint fflags for EVFILT_VNODE, shared with userspace
    233  */
    234 #define NOTE_DELETE     0x00000001              /* vnode was removed */
    235 #define NOTE_WRITE      0x00000002              /* data contents changed */
    236 #define NOTE_EXTEND     0x00000004              /* size increased */
    237 #define NOTE_ATTRIB     0x00000008              /* attributes changed */
    238 #define NOTE_LINK       0x00000010              /* link count changed */
    239 #define NOTE_RENAME     0x00000020              /* vnode was renamed */
    240 #define NOTE_REVOKE     0x00000040              /* vnode access was revoked */
    241 #define NOTE_NONE       0x00000080              /* No specific vnode event: to test for EVFILT_READ activation*/
    242 #define NOTE_FUNLOCK    0x00000100              /* vnode was unlocked by flock(2) */
    243 #define NOTE_LEASE_DOWNGRADE 0x00000200         /* lease downgrade requested */
    244 #define NOTE_LEASE_RELEASE 0x00000400           /* lease release requested */
    245 
    246 /*
    247  * data/hint fflags for EVFILT_PROC, shared with userspace
    248  *
    249  * Please note that EVFILT_PROC and EVFILT_SIGNAL share the same knote list
    250  * that hangs off the proc structure. They also both play games with the hint
    251  * passed to KNOTE(). If NOTE_SIGNAL is passed as a hint, then the lower bits
    252  * of the hint contain the signal. IF NOTE_FORK is passed, then the lower bits
    253  * contain the PID of the child (but the pid does not get passed through in
    254  * the actual kevent).
    255  */
    256 enum {
    257 	eNoteReapDeprecated __deprecated_enum_msg("This kqueue(2) EVFILT_PROC flag is deprecated") = 0x10000000
    258 };
    259 
    260 #define NOTE_EXIT               0x80000000      /* process exited */
    261 #define NOTE_FORK               0x40000000      /* process forked */
    262 #define NOTE_EXEC               0x20000000      /* process exec'd */
    263 #define NOTE_REAP               ((unsigned int)eNoteReapDeprecated /* 0x10000000 */ )   /* process reaped */
    264 #define NOTE_SIGNAL             0x08000000      /* shared with EVFILT_SIGNAL */
    265 #define NOTE_EXITSTATUS         0x04000000      /* exit status to be returned, valid for child process or when allowed to signal target pid */
    266 #define NOTE_EXIT_DETAIL        0x02000000      /* provide details on reasons for exit */
    267 
    268 #define NOTE_PDATAMASK  0x000fffff              /* mask for signal & exit status */
    269 #define NOTE_PCTRLMASK  (~NOTE_PDATAMASK)
    270 
    271 /*
    272  * If NOTE_EXITSTATUS is present, provide additional info about exiting process.
    273  */
    274 enum {
    275 	eNoteExitReparentedDeprecated __deprecated_enum_msg("This kqueue(2) EVFILT_PROC flag is no longer sent") = 0x00080000
    276 };
    277 #define NOTE_EXIT_REPARENTED    ((unsigned int)eNoteExitReparentedDeprecated)   /* exited while reparented */
    278 
    279 /*
    280  * If NOTE_EXIT_DETAIL is present, these bits indicate specific reasons for exiting.
    281  */
    282 #define NOTE_EXIT_DETAIL_MASK           0x00070000
    283 #define NOTE_EXIT_DECRYPTFAIL           0x00010000
    284 #define NOTE_EXIT_MEMORY                0x00020000
    285 #define NOTE_EXIT_CSERROR               0x00040000
    286 
    287 /*
    288  * data/hint fflags for EVFILT_VM, shared with userspace.
    289  */
    290 #define NOTE_VM_PRESSURE                        0x80000000              /* will react on memory pressure */
    291 #define NOTE_VM_PRESSURE_TERMINATE              0x40000000              /* will quit on memory pressure, possibly after cleaning up dirty state */
    292 #define NOTE_VM_PRESSURE_SUDDEN_TERMINATE       0x20000000              /* will quit immediately on memory pressure */
    293 #define NOTE_VM_ERROR                           0x10000000              /* there was an error */
    294 
    295 /*
    296  * data/hint fflags for EVFILT_TIMER, shared with userspace.
    297  * The default is a (repeating) interval timer with the data
    298  * specifying the timeout interval in milliseconds.
    299  *
    300  * All timeouts are implicitly EV_CLEAR events.
    301  */
    302 #define NOTE_SECONDS    0x00000001              /* data is seconds         */
    303 #define NOTE_USECONDS   0x00000002              /* data is microseconds    */
    304 #define NOTE_NSECONDS   0x00000004              /* data is nanoseconds     */
    305 #define NOTE_ABSOLUTE   0x00000008              /* absolute timeout        */
    306 /* ... implicit EV_ONESHOT, timeout uses the gettimeofday epoch */
    307 #define NOTE_LEEWAY             0x00000010              /* ext[1] holds leeway for power aware timers */
    308 #define NOTE_CRITICAL   0x00000020              /* system does minimal timer coalescing */
    309 #define NOTE_BACKGROUND 0x00000040              /* system does maximum timer coalescing */
    310 #define NOTE_MACH_CONTINUOUS_TIME       0x00000080
    311 /*
    312  * NOTE_MACH_CONTINUOUS_TIME:
    313  * with NOTE_ABSOLUTE: causes the timer to continue to tick across sleep,
    314  *      still uses gettimeofday epoch
    315  * with NOTE_MACHTIME and NOTE_ABSOLUTE: uses mach continuous time epoch
    316  * without NOTE_ABSOLUTE (interval timer mode): continues to tick across sleep
    317  */
    318 #define NOTE_MACHTIME   0x00000100              /* data is mach absolute time units */
    319 /* timeout uses the mach absolute time epoch */
    320 
    321 /*
    322  * data/hint fflags for EVFILT_MACHPORT, shared with userspace.
    323  *
    324  * Only portsets are supported at this time.
    325  *
    326  * The fflags field can optionally contain the MACH_RCV_MSG, MACH_RCV_LARGE,
    327  * and related trailer receive options as defined in <mach/message.h>.
    328  * The presence of these flags directs the kevent64() call to attempt to receive
    329  * the message during kevent delivery, rather than just indicate that a message exists.
    330  * On setup, The ext[0] field contains the receive buffer pointer and ext[1] contains
    331  * the receive buffer length.  Upon event delivery, the actual received message size
    332  * is returned in ext[1].  As with mach_msg(), the buffer must be large enough to
    333  * receive the message and the requested (or default) message trailers.  In addition,
    334  * the fflags field contains the return code normally returned by mach_msg().
    335  *
    336  * If MACH_RCV_MSG is specified, and the ext[1] field specifies a zero length, the
    337  * system call argument specifying an ouput area (kevent_qos) will be consulted. If
    338  * the system call specified an output data area, the user-space address
    339  * of the received message is carved from that provided output data area (if enough
    340  * space remains there). The address and length of each received message is
    341  * returned in the ext[0] and ext[1] fields (respectively) of the corresponding kevent.
    342  *
    343  * IF_MACH_RCV_VOUCHER_CONTENT is specified, the contents of the message voucher is
    344  * extracted (as specified in the xflags field) and stored in ext[2] up to ext[3]
    345  * length.  If the input length is zero, and the system call provided a data area,
    346  * the space for the voucher content is carved from the provided space and its
    347  * address and length is returned in ext[2] and ext[3] respectively.
    348  *
    349  * If no message receipt options were provided in the fflags field on setup, no
    350  * message is received by this call. Instead, on output, the data field simply
    351  * contains the name of the actual port detected with a message waiting.
    352  */
    353 
    354 /*
    355  * DEPRECATED!!!!!!!!!
    356  * NOTE_TRACK, NOTE_TRACKERR, and NOTE_CHILD are no longer supported as of 10.5
    357  */
    358 /* additional flags for EVFILT_PROC */
    359 #define NOTE_TRACK      0x00000001              /* follow across forks */
    360 #define NOTE_TRACKERR   0x00000002              /* could not track child */
    361 #define NOTE_CHILD      0x00000004              /* am a child process */
    362 
    363 
    364 /* Temporary solution for BootX to use inode.h till kqueue moves to vfs layer */
    365 struct knote;
    366 SLIST_HEAD(klist, knote);
    367 
    368 struct timespec;
    369 
    370 __BEGIN_DECLS
    371 int     kqueue(void);
    372 int     kevent(int kq,
    373     const struct kevent *changelist, int nchanges,
    374     struct kevent *eventlist, int nevents,
    375     const struct timespec *timeout);
    376 int     kevent64(int kq,
    377     const struct kevent64_s *changelist, int nchanges,
    378     struct kevent64_s *eventlist, int nevents,
    379     unsigned int flags,
    380     const struct timespec *timeout);
    381 
    382 __END_DECLS
    383 
    384 
    385 
    386 
    387 #endif /* !_SYS_EVENT_H_ */