1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 2020 Alexander V. Chernikov 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 */ 27 28 #ifndef _NET_ROUTE_NHOP_UTILS_H_ 29 #define _NET_ROUTE_NHOP_UTILS_H_ 30 31 /* Chained hash table */ 32 struct _cht_head { 33 uint32_t hash_size; 34 uint32_t items_count; 35 void **ptr; 36 }; 37 38 static inline uint32_t 39 _cht_get_resize_size(const struct _cht_head *head) 40 { 41 uint32_t new_size = 0; 42 43 if ((head->items_count * 2 > head->hash_size) && (head->hash_size < 65536)) 44 new_size = head->hash_size * 2; 45 else if ((head->items_count * 4 < head->hash_size) && head->hash_size > 16) 46 new_size = head->hash_size / 2; 47 48 return (new_size); 49 } 50 51 static inline int 52 _cht_need_resize(const struct _cht_head *head) 53 { 54 55 return (_cht_get_resize_size(head) > 0); 56 } 57 58 #ifndef typeof 59 #define typeof __typeof 60 #endif 61 62 #define CHT_SLIST_NEED_RESIZE(_head) \ 63 _cht_need_resize((const struct _cht_head *)(_head)) 64 #define CHT_SLIST_GET_RESIZE_BUCKETS(_head) \ 65 _cht_get_resize_size((const struct _cht_head *)(_head)) 66 #define CHT_SLIST_GET_RESIZE_SIZE(_buckets) ((_buckets) * sizeof(void *)) 67 68 #define CHT_SLIST_DEFINE(_HNAME, _ITEM_TYPE) \ 69 struct _HNAME##_head { \ 70 uint32_t hash_size; \ 71 uint32_t items_count; \ 72 _ITEM_TYPE **ptr; \ 73 } 74 75 #define CHT_SLIST_INIT(_head, _ptr, _num_buckets) \ 76 (_head)->hash_size = _num_buckets; \ 77 (_head)->items_count = 0; \ 78 (_head)->ptr = _ptr; 79 80 /* Default hash method for constant-size keys */ 81 82 #define CHT_GET_BUCK(_head, _PX, _key) _PX##_hash_key(_key) & ((_head)->hash_size - 1) 83 #define CHT_GET_BUCK_OBJ(_head, _PX, _obj) _PX##_hash_obj(_obj) & ((_head)->hash_size - 1) 84 85 #define CHT_FIRST(_head, idx) _CHT_FIRST((_head)->ptr, idx) 86 #define _CHT_FIRST(_ptr, idx) (_ptr)[idx] 87 88 #define CHT_SLIST_FIND(_head, _PX, _key, _ret) do { \ 89 uint32_t _buck = CHT_GET_BUCK(_head, _PX, _key); \ 90 _ret = CHT_FIRST(_head, _buck); \ 91 for ( ; _ret != NULL; _ret = _PX##_next(_ret)) { \ 92 if (_PX##_cmp(_key, (_ret))) \ 93 break; \ 94 } \ 95 } while(0) 96 97 /* 98 * hash_obj, nhop_cmp 99 */ 100 #define CHT_SLIST_FIND_BYOBJ(_head, _PX, _obj, _ret) do { \ 101 uint32_t _buck = CHT_GET_BUCK_OBJ(_head, _PX, _obj); \ 102 _ret = CHT_FIRST(_head, _buck); \ 103 for ( ; _ret != NULL; _ret = _PX##_next(_ret)) { \ 104 if (_PX##_cmp(_obj, _ret)) \ 105 break; \ 106 } \ 107 } while(0) 108 109 #define CHT_SLIST_INSERT_HEAD(_head, _PX, _obj) do { \ 110 uint32_t _buck = CHT_GET_BUCK_OBJ(_head, _PX, _obj); \ 111 _PX##_next(_obj) = CHT_FIRST(_head, _buck); \ 112 CHT_FIRST(_head, _buck) = _obj; \ 113 (_head)->items_count++; \ 114 } while(0) 115 116 #define CHT_SLIST_REMOVE(_head, _PX, _obj, _ret) do { \ 117 typeof(*(_head)->ptr) _tmp; \ 118 uint32_t _buck = CHT_GET_BUCK_OBJ(_head, _PX, _obj); \ 119 _ret = CHT_FIRST(_head, _buck); \ 120 _tmp = NULL; \ 121 for ( ; _ret != NULL; _tmp = _ret, _ret = _PX##_next(_ret)) { \ 122 if (_obj == _ret) \ 123 break; \ 124 } \ 125 if (_ret != NULL) { \ 126 if (_tmp == NULL) \ 127 CHT_FIRST(_head, _buck) = _PX##_next(_ret); \ 128 else \ 129 _PX##_next(_tmp) = _PX##_next(_ret); \ 130 (_head)->items_count--; \ 131 } \ 132 } while(0) 133 #define CHT_SLIST_REMOVE_BYOBJ CHT_SLIST_REMOVE 134 135 #define CHT_SLIST_FOREACH(_head, _PX, _x) \ 136 for (uint32_t _i = 0; _i < (_head)->hash_size; _i++) { \ 137 for (_x = CHT_FIRST(_head, _i); _x; _x = _PX##_next(_x)) 138 #define CHT_SLIST_FOREACH_END } 139 140 #define CHT_SLIST_FOREACH_SAFE(_head, _PX, _x, _tmp) \ 141 for (uint32_t _i = 0; _i < (_head)->hash_size; _i++) { \ 142 for (_x = CHT_FIRST(_head, _i); (_tmp = _PX##_next(_x), _x); _x = _tmp) 143 #define CHT_SLIST_FOREACH_SAFE_END } 144 145 #define CHT_SLIST_RESIZE(_head, _PX, _new_void_ptr, _new_hsize) \ 146 uint32_t _new_idx; \ 147 typeof((_head)->ptr) _new_ptr = (void *)_new_void_ptr; \ 148 typeof(*(_head)->ptr) _x, _y; \ 149 for (uint32_t _old_idx = 0; _old_idx < (_head)->hash_size; _old_idx++) {\ 150 _x = CHT_FIRST(_head, _old_idx); \ 151 _y = _x; \ 152 while (_y != NULL) { \ 153 _y = _PX##_next(_x); \ 154 _new_idx = _PX##_hash_obj(_x) & (_new_hsize - 1);\ 155 _PX##_next(_x) = _CHT_FIRST(_new_ptr, _new_idx);\ 156 _CHT_FIRST(_new_ptr, _new_idx) = _x; \ 157 _x = _y; \ 158 } \ 159 } \ 160 (_head)->hash_size = _new_hsize; \ 161 _new_void_ptr = (void *)(_head)->ptr; \ 162 (_head)->ptr = _new_ptr; 163 164 /* bitmasks */ 165 166 struct bitmask_head { 167 uint16_t free_off; /* index of the first potentially free block */ 168 uint16_t blocks; /* number of 4/8-byte blocks in the index */ 169 uint32_t items_count; /* total number of items */ 170 u_long *idx; 171 }; 172 173 size_t bitmask_get_size(uint32_t items); 174 uint32_t bitmask_get_resize_items(const struct bitmask_head *nh); 175 int bitmask_should_resize(const struct bitmask_head *bh); 176 void bitmask_swap(struct bitmask_head *bh, void *new_idx, uint32_t new_items, void **pidx); 177 void bitmask_init(struct bitmask_head *bh, void *idx, uint32_t num_items); 178 int bitmask_copy(const struct bitmask_head *bi, void *new_idx, uint32_t new_items); 179 int bitmask_alloc_idx(struct bitmask_head *bi, uint16_t *pidx); 180 int bitmask_free_idx(struct bitmask_head *bi, uint16_t idx); 181 182 #endif 183