StdLib/Include/sys/callout.h

   1 /*      $NetBSD: callout.h,v 1.22 2005/12/11 12:25:20 christos Exp $    */
   2
   3 /*-
   4  * Copyright (c) 2000, 2003 The NetBSD Foundation, Inc.
   5  * All rights reserved.
   6  *
   7  * This code is derived from software contributed to The NetBSD Foundation
   8  * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
   9  * NASA Ames Research Center.
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  14  * 1. Redistributions of source code must retain the above copyright
  15  *    notice, this list of conditions and the following disclaimer.
  16  * 2. Redistributions in binary form must reproduce the above copyright
  17  *    notice, this list of conditions and the following disclaimer in the
  18  *    documentation and/or other materials provided with the distribution.
  19  * 3. All advertising materials mentioning features or use of this software
  20  *    must display the following acknowledgement:
  21  *      This product includes software developed by the NetBSD
  22  *      Foundation, Inc. and its contributors.
  23  * 4. Neither the name of The NetBSD Foundation nor the names of its
  24  *    contributors may be used to endorse or promote products derived
  25  *    from this software without specific prior written permission.
  26  *
  27  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
  28  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  29  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  30  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
  31  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  32  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  33  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  34  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  35  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  36  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  37  * POSSIBILITY OF SUCH DAMAGE.
  38  */
  39
  40 /*
  41  * Copyright (c) 2000-2001 Artur Grabowski <art@openbsd.org>
  42  * All rights reserved.
  43  *
  44  * Redistribution and use in source and binary forms, with or without
  45  * modification, are permitted provided that the following conditions
  46  * are met:
  47  *
  48  * 1. Redistributions of source code must retain the above copyright
  49  *    notice, this list of conditions and the following disclaimer.
  50  * 2. Redistributions in binary form must reproduce the above copyright
  51  *    notice, this list of conditions and the following disclaimer in the
  52  *    documentation and/or other materials provided with the distribution.
  53  * 3. The name of the author may not be used to endorse or promote products
  54  *    derived from this software without specific prior written permission.
  55  *
  56  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
  57  * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
  58  * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
  59  * THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  60  * EXEMPLARY, OR CONSEQUENTIAL  DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  61  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
  62  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
  63  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
  64  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
  65  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  66  */
  67
  68 #ifndef _SYS_CALLOUT_H_
  69 #define _SYS_CALLOUT_H_
  70
  71 /*
  72  * The following funkyness is to appease gcc3's strict aliasing.
  73  */
  74 struct callout;
  75 struct callout_circq {
  76         /* next element */
  77         union {
  78                 struct callout          *elem;
  79                 struct callout_circq    *list;
  80         } cq_next;
  81         /* previous element */
  82         union {
  83                 struct callout          *elem;
  84                 struct callout_circq    *list;
  85         } cq_prev;
  86 };
  87 #define cq_next_e       cq_next.elem
  88 #define cq_prev_e       cq_prev.elem
  89 #define cq_next_l       cq_next.list
  90 #define cq_prev_l       cq_prev.list
  91
  92 struct callout {
  93         struct callout_circq c_list;            /* linkage on queue */
  94         void    (*c_func)(void *);              /* function to call */
  95         void    *c_arg;                         /* function argument */
  96         int     c_time;                         /* when callout fires */
  97         int     c_flags;                        /* state of this entry */
  98 };
  99
 100 #define CALLOUT_PENDING         0x0002  /* callout is on the queue */
 101 #define CALLOUT_FIRED           0x0004  /* callout has fired */
 102 #define CALLOUT_INVOKING        0x0008  /* callout function is being invoked */
 103
 104 #define CALLOUT_INITIALIZER_SETFUNC(func, arg)                          \
 105                                 { {{NULL}, {NULL}}, func, arg, 0, 0 }
 106
 107 #define CALLOUT_INITIALIZER     CALLOUT_INITIALIZER_SETFUNC(NULL, NULL)
 108
 109 #ifdef _KERNEL
 110 void    callout_startup(void);
 111 void    callout_init(struct callout *);
 112 void    callout_setfunc(struct callout *, void (*)(void *), void *);
 113 void    callout_reset(struct callout *, int, void (*)(void *), void *);
 114 void    callout_schedule(struct callout *, int);
 115 void    callout_stop(struct callout *);
 116 int     callout_hardclock(void);
 117
 118 #define callout_setfunc(c, f, a)                                        \
 119 do {                                                                    \
 120         (c)->c_func = (f);                                              \
 121         (c)->c_arg = (a);                                               \
 122 } while (/*CONSTCOND*/0)
 123
 124 #define callout_pending(c)      ((c)->c_flags & CALLOUT_PENDING)
 125 #define callout_expired(c)      ((c)->c_flags & CALLOUT_FIRED)
 126 #define callout_active(c)       ((c)->c_flags & (CALLOUT_PENDING|CALLOUT_FIRED))
 127 #define callout_invoking(c)     ((c)->c_flags & CALLOUT_INVOKING)
 128 #define callout_ack(c)          ((c)->c_flags &= ~CALLOUT_INVOKING)
 129 #endif /* _KERNEL */
 130
 131 #endif /* !_SYS_CALLOUT_H_ */