bsd/netat/at_ddp_brt.h

   1 /*
   2  * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
   7  *
   8  * This file contains Original Code and/or Modifications of Original Code
   9  * as defined in and that are subject to the Apple Public Source License
  10  * Version 2.0 (the 'License'). You may not use this file except in
  11  * compliance with the License. Please obtain a copy of the License at
  12  * http://www.opensource.apple.com/apsl/ and read it before using this
  13  * file.
  14  *
  15  * The Original Code and all software distributed under the License are
  16  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  17  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  18  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  20  * Please see the License for the specific language governing rights and
  21  * limitations under the License.
  22  *
  23  * @APPLE_LICENSE_HEADER_END@
  24  */
  25
  26 /*
  27  *      Copyright (c) 1988, 1989 Apple Computer, Inc.
  28  */
  29
  30 #ifndef _NETAT_AT_DDP_BRT_H_
  31 #define _NETAT_AT_DDP_BRT_H_
  32 #include <sys/appleapiopts.h>
  33 #ifdef __APPLE_API_PRIVATE
  34
  35 typedef struct {
  36         int                             age_flag;
  37         at_ifaddr_t                     *ifID;
  38         struct  etalk_addr              et_addr;
  39         at_net_al                       net;
  40 } ddp_brt_t;
  41
  42 #define BRT_SWEEP_INT           (10 * PR_SLOWHZ)
  43 #define BRT_BSIZ                 4      /* bucket size */
  44 #define BRT_NB                  16      /* number of buckets */
  45 #define BRTSIZE                 (BRT_BSIZ * BRT_NB)
  46
  47 /* age_flag values */
  48 #define BRT_EMPTY               0       /* the BRT entry is empty     */
  49                                         /* (or aged out).             */
  50 #define BRT_VALID               1       /* BRT entry contains valid   */
  51                                         /* tuple                      */
  52 #define BRT_GETTING_OLD         2       /* BRT entry is a candidate   */
  53                                         /* for aging                  */
  54
  55 #define BRT_HASH(a)   ((a) % BRT_NB)
  56
  57 #define BRT_LOOK(brt, dst_net) {                                \
  58         register n;                                             \
  59         brt = &at_ddp_brt[BRT_HASH(dst_net) * BRT_BSIZ];        \
  60         for (n = 0 ; ; brt++) {                                 \
  61                 if (brt->net == dst_net)                        \
  62                         break;                                  \
  63                 if (++n >= BRT_BSIZ) {                          \
  64                         brt = NULL;                             \
  65                         break;                                  \
  66                 }                                               \
  67         }                                                       \
  68         }
  69
  70 #define NEW_BRT(brt, net) {                                     \
  71         register n;                                             \
  72         brt = &at_ddp_brt[BRT_HASH(net) * BRT_BSIZ];            \
  73         for (n = 0 ; ; brt++) {                                 \
  74                 if (brt->age_flag == BRT_EMPTY)                 \
  75                         break;                                  \
  76                 if (++n >= BRT_BSIZ) {                          \
  77                         brt = NULL;                             \
  78                         break;                                  \
  79                 }                                               \
  80         }                                                       \
  81         }
  82
  83 /* Best Router Cache */
  84 extern  ddp_brt_t       at_ddp_brt[BRTSIZE];
  85
  86 #endif /* __APPLE_API_PRIVATE */
  87 #endif /* _NETAT_AT_DDP_BRT_H_ */
  88