| 1 | /* $NetBSD: ipf_rb.h,v 1.5 2013/01/09 13:23:20 christos Exp $ */ |
| 2 | |
| 3 | /* |
| 4 | * Copyright (C) 2012 by Darren Reed. |
| 5 | * |
| 6 | * See the IPFILTER.LICENCE file for details on licencing. |
| 7 | * |
| 8 | */ |
| 9 | |
| 10 | /* |
| 11 | * If the OS has a red-black tree implementation, use it. |
| 12 | */ |
| 13 | #ifdef HAVE_RBTREE |
| 14 | |
| 15 | #include <sys/rbtree.h> |
| 16 | |
| 17 | # define RBI_LINK(_n, _t) |
| 18 | # define RBI_FIELD(_n) rb_node_t |
| 19 | # define RBI_HEAD(_n, _t) rb_tree_t |
| 20 | |
| 21 | /* Define adapter code between the ipf-specific and the system rb impls. */ |
| 22 | # define RBI_CODE(_n, _t, _f, _cmp) \ |
| 23 | signed int _n##_compare_nodes(void *ctx, const void *n1, const void *n2);\ |
| 24 | signed int _n##_compare_key(void *ctx, const void *n1, const void *key);\ |
| 25 | typedef void (*_n##_rb_walker_t)(_t *, void *); \ |
| 26 | void _n##_rb_walktree(rb_tree_t *, _n##_rb_walker_t, void *); \ |
| 27 | \ |
| 28 | static const rb_tree_ops_t _n##_tree_ops = { \ |
| 29 | .rbto_compare_nodes = _n##_compare_nodes, \ |
| 30 | .rbto_compare_key = _n##_compare_key, \ |
| 31 | .rbto_node_offset = offsetof(_t, _f), \ |
| 32 | .rbto_context = NULL \ |
| 33 | }; \ |
| 34 | \ |
| 35 | int \ |
| 36 | _n##_compare_nodes(void *ctx, const void *n1, const void *n2) { \ |
| 37 | return _cmp(n1, n2); \ |
| 38 | } \ |
| 39 | \ |
| 40 | int \ |
| 41 | _n##_compare_key(void *ctx, const void *n1, const void *key) { \ |
| 42 | return _cmp(n1, key); \ |
| 43 | } \ |
| 44 | \ |
| 45 | void \ |
| 46 | _n##_rb_walktree(rb_tree_t *head, _n##_rb_walker_t func, void *arg) \ |
| 47 | { \ |
| 48 | _t *rb; \ |
| 49 | /* Take advantage of the fact that the ipf code only uses this \ |
| 50 | method to clear the tree, in order to do it more safely. */ \ |
| 51 | while ((rb = rb_tree_iterate(head, NULL, RB_DIR_RIGHT)) != NULL) {\ |
| 52 | rb_tree_remove_node(head, rb); \ |
| 53 | func(rb, arg); \ |
| 54 | } \ |
| 55 | } |
| 56 | |
| 57 | # define RBI_DELETE(_n, _h, _v) rb_tree_remove_node(_h, _v) |
| 58 | # define RBI_INIT(_n, _h) rb_tree_init(_h, &_n##_tree_ops) |
| 59 | # define RBI_INSERT(_n, _h, _v) rb_tree_insert_node(_h, _v) |
| 60 | # define RBI_ISEMPTY(_h) (rb_tree_iterate(_h, NULL, RB_DIR_RIGHT) == NULL) |
| 61 | # define RBI_SEARCH(_n, _h, _k) rb_tree_find_node(_h, _k) |
| 62 | # define RBI_WALK(_n, _h, _w, _a) _n##_rb_walktree(_h, _w, _a) |
| 63 | |
| 64 | #else |
| 65 | |
| 66 | typedef enum rbcolour_e { |
| 67 | C_BLACK = 0, |
| 68 | C_RED = 1 |
| 69 | } rbcolour_t; |
| 70 | |
| 71 | #define RBI_LINK(_n, _t) \ |
| 72 | struct _n##_rb_link { \ |
| 73 | struct _t *left; \ |
| 74 | struct _t *right; \ |
| 75 | struct _t *parent; \ |
| 76 | rbcolour_t colour; \ |
| 77 | } |
| 78 | |
| 79 | #define RBI_HEAD(_n, _t) \ |
| 80 | struct _n##_rb_head { \ |
| 81 | struct _t top; \ |
| 82 | int count; \ |
| 83 | int (* compare)(struct _t *, struct _t *); \ |
| 84 | } |
| 85 | |
| 86 | #define RBI_FIELD(_n) struct _n##_rb_link |
| 87 | |
| 88 | #define RBI_CODE(_n, _t, _f, _cmp) \ |
| 89 | \ |
| 90 | _t RBI_ZERO(_n); \ |
| 91 | \ |
| 92 | typedef void (*_n##_rb_walker_t)(_t *, void *); \ |
| 93 | \ |
| 94 | _t * _n##_rb_delete(struct _n##_rb_head *, _t *); \ |
| 95 | void _n##_rb_init(struct _n##_rb_head *); \ |
| 96 | void _n##_rb_insert(struct _n##_rb_head *, _t *); \ |
| 97 | _t * _n##_rb_search(struct _n##_rb_head *, void *); \ |
| 98 | void _n##_rb_walktree(struct _n##_rb_head *, _n##_rb_walker_t, void *);\ |
| 99 | \ |
| 100 | static void \ |
| 101 | rotate_left(struct _n##_rb_head *head, _t *node) \ |
| 102 | { \ |
| 103 | _t *parent, *tmp1, *tmp2; \ |
| 104 | \ |
| 105 | parent = node->_f.parent; \ |
| 106 | tmp1 = node->_f.right; \ |
| 107 | tmp2 = tmp1->_f.left; \ |
| 108 | node->_f.right = tmp2; \ |
| 109 | if (tmp2 != & _n##_rb_zero) \ |
| 110 | tmp2->_f.parent = node; \ |
| 111 | if (parent == & _n##_rb_zero) \ |
| 112 | head->top._f.right = tmp1; \ |
| 113 | else if (parent->_f.right == node) \ |
| 114 | parent->_f.right = tmp1; \ |
| 115 | else \ |
| 116 | parent->_f.left = tmp1; \ |
| 117 | tmp1->_f.left = node; \ |
| 118 | tmp1->_f.parent = parent; \ |
| 119 | node->_f.parent = tmp1; \ |
| 120 | } \ |
| 121 | \ |
| 122 | static void \ |
| 123 | rotate_right(struct _n##_rb_head *head, _t *node) \ |
| 124 | { \ |
| 125 | _t *parent, *tmp1, *tmp2; \ |
| 126 | \ |
| 127 | parent = node->_f.parent; \ |
| 128 | tmp1 = node->_f.left; \ |
| 129 | tmp2 = tmp1->_f.right; \ |
| 130 | node->_f.left = tmp2; \ |
| 131 | if (tmp2 != &_n##_rb_zero) \ |
| 132 | tmp2->_f.parent = node; \ |
| 133 | if (parent == &_n##_rb_zero) \ |
| 134 | head->top._f.right = tmp1; \ |
| 135 | else if (parent->_f.right == node) \ |
| 136 | parent->_f.right = tmp1; \ |
| 137 | else \ |
| 138 | parent->_f.left = tmp1; \ |
| 139 | tmp1->_f.right = node; \ |
| 140 | tmp1->_f.parent = parent; \ |
| 141 | node->_f.parent = tmp1; \ |
| 142 | } \ |
| 143 | \ |
| 144 | void \ |
| 145 | _n##_rb_insert(struct _n##_rb_head *head, _t *node) \ |
| 146 | { \ |
| 147 | _t *n, *parent, **p, *tmp1, *gparent; \ |
| 148 | \ |
| 149 | parent = &head->top; \ |
| 150 | node->_f.left = &_n##_rb_zero; \ |
| 151 | node->_f.right = &_n##_rb_zero; \ |
| 152 | p = &head->top._f.right; \ |
| 153 | while ((n = *p) != &_n##_rb_zero) { \ |
| 154 | if (_cmp(node, n) < 0) \ |
| 155 | p = &n->_f.left; \ |
| 156 | else \ |
| 157 | p = &n->_f.right; \ |
| 158 | parent = n; \ |
| 159 | } \ |
| 160 | *p = node; \ |
| 161 | node->_f.colour = C_RED; \ |
| 162 | node->_f.parent = parent; \ |
| 163 | \ |
| 164 | while ((node != &_n##_rb_zero) && (parent->_f.colour == C_RED)){\ |
| 165 | gparent = parent->_f.parent; \ |
| 166 | if (parent == gparent->_f.left) { \ |
| 167 | tmp1 = gparent->_f.right; \ |
| 168 | if (tmp1->_f.colour == C_RED) { \ |
| 169 | parent->_f.colour = C_BLACK; \ |
| 170 | tmp1->_f.colour = C_BLACK; \ |
| 171 | gparent->_f.colour = C_RED; \ |
| 172 | node = gparent; \ |
| 173 | } else { \ |
| 174 | if (node == parent->_f.right) { \ |
| 175 | node = parent; \ |
| 176 | rotate_left(head, node); \ |
| 177 | parent = node->_f.parent; \ |
| 178 | } \ |
| 179 | parent->_f.colour = C_BLACK; \ |
| 180 | gparent->_f.colour = C_RED; \ |
| 181 | rotate_right(head, gparent); \ |
| 182 | } \ |
| 183 | } else { \ |
| 184 | tmp1 = gparent->_f.left; \ |
| 185 | if (tmp1->_f.colour == C_RED) { \ |
| 186 | parent->_f.colour = C_BLACK; \ |
| 187 | tmp1->_f.colour = C_BLACK; \ |
| 188 | gparent->_f.colour = C_RED; \ |
| 189 | node = gparent; \ |
| 190 | } else { \ |
| 191 | if (node == parent->_f.left) { \ |
| 192 | node = parent; \ |
| 193 | rotate_right(head, node); \ |
| 194 | parent = node->_f.parent; \ |
| 195 | } \ |
| 196 | parent->_f.colour = C_BLACK; \ |
| 197 | gparent->_f.colour = C_RED; \ |
| 198 | rotate_left(head, parent->_f.parent); \ |
| 199 | } \ |
| 200 | } \ |
| 201 | parent = node->_f.parent; \ |
| 202 | } \ |
| 203 | head->top._f.right->_f.colour = C_BLACK; \ |
| 204 | head->count++; \ |
| 205 | } \ |
| 206 | \ |
| 207 | static void \ |
| 208 | deleteblack(struct _n##_rb_head *head, _t *parent, _t *node) \ |
| 209 | { \ |
| 210 | _t *tmp; \ |
| 211 | \ |
| 212 | while ((node == &_n##_rb_zero || node->_f.colour == C_BLACK) && \ |
| 213 | node != &head->top) { \ |
| 214 | if (parent->_f.left == node) { \ |
| 215 | tmp = parent->_f.right; \ |
| 216 | if (tmp->_f.colour == C_RED) { \ |
| 217 | tmp->_f.colour = C_BLACK; \ |
| 218 | parent->_f.colour = C_RED; \ |
| 219 | rotate_left(head, parent); \ |
| 220 | tmp = parent->_f.right; \ |
| 221 | } \ |
| 222 | if ((tmp->_f.left == &_n##_rb_zero || \ |
| 223 | tmp->_f.left->_f.colour == C_BLACK) && \ |
| 224 | (tmp->_f.right == &_n##_rb_zero || \ |
| 225 | tmp->_f.right->_f.colour == C_BLACK)) { \ |
| 226 | tmp->_f.colour = C_RED; \ |
| 227 | node = parent; \ |
| 228 | parent = node->_f.parent; \ |
| 229 | } else { \ |
| 230 | if (tmp->_f.right == &_n##_rb_zero || \ |
| 231 | tmp->_f.right->_f.colour == C_BLACK) {\ |
| 232 | _t *tmp2 = tmp->_f.left; \ |
| 233 | \ |
| 234 | if (tmp2 != &_n##_rb_zero) \ |
| 235 | tmp2->_f.colour = C_BLACK;\ |
| 236 | tmp->_f.colour = C_RED; \ |
| 237 | rotate_right(head, tmp); \ |
| 238 | tmp = parent->_f.right; \ |
| 239 | } \ |
| 240 | tmp->_f.colour = parent->_f.colour; \ |
| 241 | parent->_f.colour = C_BLACK; \ |
| 242 | if (tmp->_f.right != &_n##_rb_zero) \ |
| 243 | tmp->_f.right->_f.colour = C_BLACK;\ |
| 244 | rotate_left(head, parent); \ |
| 245 | node = head->top._f.right; \ |
| 246 | } \ |
| 247 | } else { \ |
| 248 | tmp = parent->_f.left; \ |
| 249 | if (tmp->_f.colour == C_RED) { \ |
| 250 | tmp->_f.colour = C_BLACK; \ |
| 251 | parent->_f.colour = C_RED; \ |
| 252 | rotate_right(head, parent); \ |
| 253 | tmp = parent->_f.left; \ |
| 254 | } \ |
| 255 | if ((tmp->_f.left == &_n##_rb_zero || \ |
| 256 | tmp->_f.left->_f.colour == C_BLACK) && \ |
| 257 | (tmp->_f.right == &_n##_rb_zero || \ |
| 258 | tmp->_f.right->_f.colour == C_BLACK)) { \ |
| 259 | tmp->_f.colour = C_RED; \ |
| 260 | node = parent; \ |
| 261 | parent = node->_f.parent; \ |
| 262 | } else { \ |
| 263 | if (tmp->_f.left == &_n##_rb_zero || \ |
| 264 | tmp->_f.left->_f.colour == C_BLACK) {\ |
| 265 | _t *tmp2 = tmp->_f.right; \ |
| 266 | \ |
| 267 | if (tmp2 != &_n##_rb_zero) \ |
| 268 | tmp2->_f.colour = C_BLACK;\ |
| 269 | tmp->_f.colour = C_RED; \ |
| 270 | rotate_left(head, tmp); \ |
| 271 | tmp = parent->_f.left; \ |
| 272 | } \ |
| 273 | tmp->_f.colour = parent->_f.colour; \ |
| 274 | parent->_f.colour = C_BLACK; \ |
| 275 | if (tmp->_f.left != &_n##_rb_zero) \ |
| 276 | tmp->_f.left->_f.colour = C_BLACK;\ |
| 277 | rotate_right(head, parent); \ |
| 278 | node = head->top._f.right; \ |
| 279 | break; \ |
| 280 | } \ |
| 281 | } \ |
| 282 | } \ |
| 283 | if (node != &_n##_rb_zero) \ |
| 284 | node->_f.colour = C_BLACK; \ |
| 285 | } \ |
| 286 | \ |
| 287 | _t * \ |
| 288 | _n##_rb_delete(struct _n##_rb_head *head, _t *node) \ |
| 289 | { \ |
| 290 | _t *child, *parent, *old = node, *left; \ |
| 291 | rbcolour_t color; \ |
| 292 | \ |
| 293 | if (node->_f.left == &_n##_rb_zero) { \ |
| 294 | child = node->_f.right; \ |
| 295 | } else if (node->_f.right == &_n##_rb_zero) { \ |
| 296 | child = node->_f.left; \ |
| 297 | } else { \ |
| 298 | node = node->_f.right; \ |
| 299 | while ((left = node->_f.left) != &_n##_rb_zero) \ |
| 300 | node = left; \ |
| 301 | child = node->_f.right; \ |
| 302 | parent = node->_f.parent; \ |
| 303 | color = node->_f.colour; \ |
| 304 | if (child != &_n##_rb_zero) \ |
| 305 | child->_f.parent = parent; \ |
| 306 | if (parent != &_n##_rb_zero) { \ |
| 307 | if (parent->_f.left == node) \ |
| 308 | parent->_f.left = child; \ |
| 309 | else \ |
| 310 | parent->_f.right = child; \ |
| 311 | } else { \ |
| 312 | head->top._f.right = child; \ |
| 313 | } \ |
| 314 | if (node->_f.parent == old) \ |
| 315 | parent = node; \ |
| 316 | *node = *old; \ |
| 317 | if (old->_f.parent != &_n##_rb_zero) { \ |
| 318 | if (old->_f.parent->_f.left == old) \ |
| 319 | old->_f.parent->_f.left = node; \ |
| 320 | else \ |
| 321 | old->_f.parent->_f.right = node; \ |
| 322 | } else { \ |
| 323 | head->top._f.right = child; \ |
| 324 | } \ |
| 325 | old->_f.left->_f.parent = node; \ |
| 326 | if (old->_f.right != &_n##_rb_zero) \ |
| 327 | old->_f.right->_f.parent = node; \ |
| 328 | if (parent != &_n##_rb_zero) { \ |
| 329 | left = parent; \ |
| 330 | } \ |
| 331 | goto colour; \ |
| 332 | } \ |
| 333 | parent = node->_f.parent; \ |
| 334 | color= node->_f.colour; \ |
| 335 | if (child != &_n##_rb_zero) \ |
| 336 | child->_f.parent = parent; \ |
| 337 | if (parent != &_n##_rb_zero) { \ |
| 338 | if (parent->_f.left == node) \ |
| 339 | parent->_f.left = child; \ |
| 340 | else \ |
| 341 | parent->_f.right = child; \ |
| 342 | } else { \ |
| 343 | head->top._f.right = child; \ |
| 344 | } \ |
| 345 | colour: \ |
| 346 | if (color == C_BLACK) \ |
| 347 | deleteblack(head, parent, node); \ |
| 348 | head->count--; \ |
| 349 | return old; \ |
| 350 | } \ |
| 351 | \ |
| 352 | void \ |
| 353 | _n##_rb_init(struct _n##_rb_head *head) \ |
| 354 | { \ |
| 355 | memset(&_n##_rb_zero, 0, sizeof(_n##_rb_zero)); \ |
| 356 | head->top._f.left = &_n##_rb_zero; \ |
| 357 | head->top._f.right = &_n##_rb_zero; \ |
| 358 | head->top._f.parent = &head->top; \ |
| 359 | _n##_rb_zero._f.left = &_n##_rb_zero; \ |
| 360 | _n##_rb_zero._f.right = &_n##_rb_zero; \ |
| 361 | _n##_rb_zero._f.parent = &_n##_rb_zero; \ |
| 362 | } \ |
| 363 | \ |
| 364 | void \ |
| 365 | _n##_rb_walktree(struct _n##_rb_head *head, _n##_rb_walker_t func, void *arg)\ |
| 366 | { \ |
| 367 | _t *prev; \ |
| 368 | _t *next; \ |
| 369 | _t *node = head->top._f.right; \ |
| 370 | _t *base; \ |
| 371 | \ |
| 372 | while (node != &_n##_rb_zero) \ |
| 373 | node = node->_f.left; \ |
| 374 | \ |
| 375 | for (;;) { \ |
| 376 | base = node; \ |
| 377 | prev = node; \ |
| 378 | while ((node->_f.parent->_f.right == node) && \ |
| 379 | (node != &_n##_rb_zero)) { \ |
| 380 | prev = node; \ |
| 381 | node = node->_f.parent; \ |
| 382 | } \ |
| 383 | \ |
| 384 | node = prev; \ |
| 385 | for (node = node->_f.parent->_f.right; node != &_n##_rb_zero;\ |
| 386 | node = node->_f.left) \ |
| 387 | prev = node; \ |
| 388 | next = prev; \ |
| 389 | \ |
| 390 | if (node != &_n##_rb_zero) \ |
| 391 | func(node, arg); \ |
| 392 | \ |
| 393 | node = next; \ |
| 394 | if (node == &_n##_rb_zero) \ |
| 395 | break; \ |
| 396 | } \ |
| 397 | } \ |
| 398 | \ |
| 399 | _t * \ |
| 400 | _n##_rb_search(struct _n##_rb_head *head, void *key) \ |
| 401 | { \ |
| 402 | int match = 0; \ |
| 403 | _t *node; \ |
| 404 | node = head->top._f.right; \ |
| 405 | while (node != &_n##_rb_zero) { \ |
| 406 | match = _cmp(key, node); \ |
| 407 | if (match == 0) \ |
| 408 | break; \ |
| 409 | if (match< 0) \ |
| 410 | node = node->_f.left; \ |
| 411 | else \ |
| 412 | node = node->_f.right; \ |
| 413 | } \ |
| 414 | if (node == &_n##_rb_zero || match != 0) \ |
| 415 | return (NULL); \ |
| 416 | return (node); \ |
| 417 | } |
| 418 | |
| 419 | #define RBI_DELETE(_n, _h, _v) _n##_rb_delete(_h, _v) |
| 420 | #define RBI_INIT(_n, _h) _n##_rb_init(_h) |
| 421 | #define RBI_INSERT(_n, _h, _v) _n##_rb_insert(_h, _v) |
| 422 | #define RBI_ISEMPTY(_h) ((_h)->count == 0) |
| 423 | #define RBI_SEARCH(_n, _h, _k) _n##_rb_search(_h, _k) |
| 424 | #define RBI_WALK(_n, _h, _w, _a) _n##_rb_walktree(_h, _w, _a) |
| 425 | #define RBI_ZERO(_n) _n##_rb_zero |
| 426 | |
| 427 | #endif |
| 428 | |