contrib/bind-9.2.4rc7/lib/isc/include/isc/event.h

   1 /*
   2  * Copyright (C) 2004  Internet Systems Consortium, Inc. ("ISC")
   3  * Copyright (C) 1998-2002  Internet Software Consortium.
   4  *
   5  * Permission to use, copy, modify, and distribute this software for any
   6  * purpose with or without fee is hereby granted, provided that the above
   7  * copyright notice and this permission notice appear in all copies.
   8  *
   9  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
  10  * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
  11  * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
  12  * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
  13  * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
  14  * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
  15  * PERFORMANCE OF THIS SOFTWARE.
  16  */
  17
  18 /* $Id: event.h,v 1.24.2.4 2004/04/15 02:16:29 marka Exp $ */
  19
  20 #ifndef ISC_EVENT_H
  21 #define ISC_EVENT_H 1
  22
  23 #include <isc/lang.h>
  24 #include <isc/types.h>
  25
  26 /*****
  27  ***** Events.
  28  *****/
  29
  30 typedef void (*isc_eventdestructor_t)(isc_event_t *);
  31
  32 #define ISC_EVENT_COMMON(ltype)         \
  33         size_t                          ev_size; \
  34         unsigned int                    ev_attributes; \
  35         void *                          ev_tag; \
  36         isc_eventtype_t                 ev_type; \
  37         isc_taskaction_t                ev_action; \
  38         void *                          ev_arg; \
  39         void *                          ev_sender; \
  40         isc_eventdestructor_t           ev_destroy; \
  41         void *                          ev_destroy_arg; \
  42         ISC_LINK(ltype)                 ev_link
  43
  44 /*
  45  * Attributes matching a mask of 0x000000ff are reserved for the task library's
  46  * definition.  Attributes of 0xffffff00 may be used by the application
  47  * or non-ISC libraries.
  48  */
  49 #define ISC_EVENTATTR_NOPURGE           0x00000001
  50
  51 /*
  52  * The ISC_EVENTATTR_CANCELED attribute is intended to indicate
  53  * that an event is delivered as a result of a canceled operation
  54  * rather than successful completion, by mutual agreement
  55  * between the sender and receiver.  It is not set or used by
  56  * the task system.
  57  */
  58 #define ISC_EVENTATTR_CANCELED          0x00000002
  59
  60 #define ISC_EVENT_INIT(event, sz, at, ta, ty, ac, ar, sn, df, da) \
  61 do { \
  62         (event)->ev_size = (sz); \
  63         (event)->ev_attributes = (at); \
  64         (event)->ev_tag = (ta); \
  65         (event)->ev_type = (ty); \
  66         (event)->ev_action = (ac); \
  67         (event)->ev_arg = (ar); \
  68         (event)->ev_sender = (sn); \
  69         (event)->ev_destroy = (df); \
  70         (event)->ev_destroy_arg = (da); \
  71         ISC_LINK_INIT((event), ev_link); \
  72 } while (0)
  73
  74 /*
  75  * This structure is public because "subclassing" it may be useful when
  76  * defining new event types.
  77  */
  78 struct isc_event {
  79         ISC_EVENT_COMMON(struct isc_event);
  80 };
  81
  82 #define ISC_EVENTTYPE_FIRSTEVENT        0x00000000
  83 #define ISC_EVENTTYPE_LASTEVENT         0xffffffff
  84
  85 #define ISC_EVENT_PTR(p) ((isc_event_t **)(void *)(p))
  86
  87 ISC_LANG_BEGINDECLS
  88
  89 isc_event_t *
  90 isc_event_allocate(isc_mem_t *mctx, void *sender, isc_eventtype_t type,
  91                    isc_taskaction_t action, const void *arg, size_t size);
  92 /*
  93  * Allocate and initialize in a structure with initial elements
  94  * defined by:
  95  *
  96  *      struct {
  97  *              ISC_EVENT_COMMON(struct isc_event);
  98  *              ...
  99  *      };
 100  *
 101  * Requires:
 102  *      'size' >= sizeof(struct isc_event)
 103  *      'action' to be non NULL
 104  *
 105  * Returns:
 106  *      a pointer to a initialized structure of the requested size.
 107  *      NULL if unable to allocate memory.
 108  */
 109
 110 void
 111 isc_event_free(isc_event_t **);
 112
 113 ISC_LANG_ENDDECLS
 114
 115 #endif /* ISC_EVENT_H */