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  * The contents of this file constitute Original Code as defined in and
   7  * are subject to the Apple Public Source License Version 1.1 (the
   8  * "License").  You may not use this file except in compliance with the
   9  * License.  Please obtain a copy of the License at
  10  * http://www.apple.com/publicsource and read it before using this file.
  11  *
  12  * This Original Code and all software distributed under the License are
  13  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  14  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  15  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
  17  * License for the specific language governing rights and limitations
  18  * under the License.
  19  *
  20  * @APPLE_LICENSE_HEADER_END@
  21  */
  22
  23 /*
  24  *      Copyright (c) 1988, 1989 Apple Computer, Inc.
  25  */
  26
  27 #ifndef _NETAT_AT_DDP_BRT_H_
  28 #define _NETAT_AT_DDP_BRT_H_
  29 #include <sys/appleapiopts.h>
  30 #ifdef __APPLE_API_PRIVATE
  31
  32 typedef struct {
  33         int                             age_flag;
  34         at_ifaddr_t                     *ifID;
  35         struct  etalk_addr              et_addr;
  36         at_net_al                       net;
  37 } ddp_brt_t;
  38
  39 #define BRT_SWEEP_INT           (10 * PR_SLOWHZ)
  40 #define BRT_BSIZ                 4      /* bucket size */
  41 #define BRT_NB                  16      /* number of buckets */
  42 #define BRTSIZE                 (BRT_BSIZ * BRT_NB)
  43
  44 /* age_flag values */
  45 #define BRT_EMPTY               0       /* the BRT entry is empty     */
  46                                         /* (or aged out).             */
  47 #define BRT_VALID               1       /* BRT entry contains valid   */
  48                                         /* tuple                      */
  49 #define BRT_GETTING_OLD         2       /* BRT entry is a candidate   */
  50                                         /* for aging                  */
  51
  52 #define BRT_HASH(a)   ((a) % BRT_NB)
  53
  54 #define BRT_LOOK(brt, dst_net) {                                \
  55         register n;                                             \
  56         brt = &at_ddp_brt[BRT_HASH(dst_net) * BRT_BSIZ];        \
  57         for (n = 0 ; ; brt++) {                                 \
  58                 if (brt->net == dst_net)                        \
  59                         break;                                  \
  60                 if (++n >= BRT_BSIZ) {                          \
  61                         brt = NULL;                             \
  62                         break;                                  \
  63                 }                                               \
  64         }                                                       \
  65         }
  66
  67 #define NEW_BRT(brt, net) {                                     \
  68         register n;                                             \
  69         brt = &at_ddp_brt[BRT_HASH(net) * BRT_BSIZ];            \
  70         for (n = 0 ; ; brt++) {                                 \
  71                 if (brt->age_flag == BRT_EMPTY)                 \
  72                         break;                                  \
  73                 if (++n >= BRT_BSIZ) {                          \
  74                         brt = NULL;                             \
  75                         break;                                  \
  76                 }                                               \
  77         }                                                       \
  78         }
  79
  80 /* Best Router Cache */
  81 extern  ddp_brt_t       at_ddp_brt[BRTSIZE];
  82
  83 #endif /* __APPLE_API_PRIVATE */
  84 #endif /* _NETAT_AT_DDP_BRT_H_ */
  85