lwext4/tree.h

   1 /*      $NetBSD: tree.h,v 1.8 2004/03/28 19:38:30 provos Exp $  */
   2 /*      $OpenBSD: tree.h,v 1.7 2002/10/17 21:51:54 art Exp $    */
   3 /* $FreeBSD$ */
   4
   5 /*-
   6  * Copyright 2002 Niels Provos <provos@citi.umich.edu>
   7  * All rights reserved.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in the
  16  *    documentation and/or other materials provided with the distribution.
  17  *
  18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  19  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  20  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  21  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  22  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  23  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  24  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  25  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  26  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  27  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  28  */
  29
  30 #ifndef _SYS_TREE_H_
  31 #define _SYS_TREE_H_
  32
  33 #ifdef __GNUC__
  34 #ifndef __unused
  35 #define __unused __attribute__ ((__unused__))
  36 #endif
  37 #endif
  38 /*
  39  * This file defines data structures for different types of trees:
  40  * splay trees and red-black trees.
  41  *
  42  * A splay tree is a self-organizing data structure.  Every operation
  43  * on the tree causes a splay to happen.  The splay moves the requested
  44  * node to the root of the tree and partly rebalances it.
  45  *
  46  * This has the benefit that request locality causes faster lookups as
  47  * the requested nodes move to the top of the tree.  On the other hand,
  48  * every lookup causes memory writes.
  49  *
  50  * The Balance Theorem bounds the total access time for m operations
  51  * and n inserts on an initially empty tree as O((m + n)lg n).  The
  52  * amortized cost for a sequence of m accesses to a splay tree is O(lg n);
  53  *
  54  * A red-black tree is a binary search tree with the node color as an
  55  * extra attribute.  It fulfills a set of conditions:
  56  *      - every search path from the root to a leaf consists of the
  57  *        same number of black nodes,
  58  *      - each red node (except for the root) has a black parent,
  59  *      - each leaf node is black.
  60  *
  61  * Every operation on a red-black tree is bounded as O(lg n).
  62  * The maximum height of a red-black tree is 2lg (n+1).
  63  */
  64
  65 #define SPLAY_HEAD(name, type)                                          \
  66 struct name {                                                           \
  67         struct type *sph_root; /* root of the tree */                   \
  68 }
  69
  70 #define SPLAY_INITIALIZER(root)                                         \
  71         { NULL }
  72
  73 #define SPLAY_INIT(root) do {                                           \
  74         (root)->sph_root = NULL;                                        \
  75 } while (/*CONSTCOND*/ 0)
  76
  77 #define SPLAY_ENTRY(type)                                               \
  78 struct {                                                                \
  79         struct type *spe_left; /* left element */                       \
  80         struct type *spe_right; /* right element */                     \
  81 }
  82
  83 #define SPLAY_LEFT(elm, field)          (elm)->field.spe_left
  84 #define SPLAY_RIGHT(elm, field)         (elm)->field.spe_right
  85 #define SPLAY_ROOT(head)                (head)->sph_root
  86 #define SPLAY_EMPTY(head)               (SPLAY_ROOT(head) == NULL)
  87
  88 /* SPLAY_ROTATE_{LEFT,RIGHT} expect that tmp hold SPLAY_{RIGHT,LEFT} */
  89 #define SPLAY_ROTATE_RIGHT(head, tmp, field) do {                       \
  90         SPLAY_LEFT((head)->sph_root, field) = SPLAY_RIGHT(tmp, field);  \
  91         SPLAY_RIGHT(tmp, field) = (head)->sph_root;                     \
  92         (head)->sph_root = tmp;                                         \
  93 } while (/*CONSTCOND*/ 0)
  94
  95 #define SPLAY_ROTATE_LEFT(head, tmp, field) do {                        \
  96         SPLAY_RIGHT((head)->sph_root, field) = SPLAY_LEFT(tmp, field);  \
  97         SPLAY_LEFT(tmp, field) = (head)->sph_root;                      \
  98         (head)->sph_root = tmp;                                         \
  99 } while (/*CONSTCOND*/ 0)
 100
 101 #define SPLAY_LINKLEFT(head, tmp, field) do {                           \
 102         SPLAY_LEFT(tmp, field) = (head)->sph_root;                      \
 103         tmp = (head)->sph_root;                                         \
 104         (head)->sph_root = SPLAY_LEFT((head)->sph_root, field);         \
 105 } while (/*CONSTCOND*/ 0)
 106
 107 #define SPLAY_LINKRIGHT(head, tmp, field) do {                          \
 108         SPLAY_RIGHT(tmp, field) = (head)->sph_root;                     \
 109         tmp = (head)->sph_root;                                         \
 110         (head)->sph_root = SPLAY_RIGHT((head)->sph_root, field);        \
 111 } while (/*CONSTCOND*/ 0)
 112
 113 #define SPLAY_ASSEMBLE(head, node, left, right, field) do {             \
 114         SPLAY_RIGHT(left, field) = SPLAY_LEFT((head)->sph_root, field); \
 115         SPLAY_LEFT(right, field) = SPLAY_RIGHT((head)->sph_root, field);\
 116         SPLAY_LEFT((head)->sph_root, field) = SPLAY_RIGHT(node, field); \
 117         SPLAY_RIGHT((head)->sph_root, field) = SPLAY_LEFT(node, field); \
 118 } while (/*CONSTCOND*/ 0)
 119
 120 /* Generates prototypes and inline functions */
 121
 122 #define SPLAY_PROTOTYPE(name, type, field, cmp)                         \
 123 void name##_SPLAY(struct name *, struct type *);                        \
 124 void name##_SPLAY_MINMAX(struct name *, int);                           \
 125 struct type *name##_SPLAY_INSERT(struct name *, struct type *);         \
 126 struct type *name##_SPLAY_REMOVE(struct name *, struct type *);         \
 127                                                                         \
 128 /* Finds the node with the same key as elm */                           \
 129 static __inline struct type *                                           \
 130 name##_SPLAY_FIND(struct name *head, struct type *elm)                  \
 131 {                                                                       \
 132         if (SPLAY_EMPTY(head))                                          \
 133                 return(NULL);                                           \
 134         name##_SPLAY(head, elm);                                        \
 135         if ((cmp)(elm, (head)->sph_root) == 0)                          \
 136                 return (head->sph_root);                                \
 137         return (NULL);                                                  \
 138 }                                                                       \
 139                                                                         \
 140 static __inline struct type *                                           \
 141 name##_SPLAY_NEXT(struct name *head, struct type *elm)                  \
 142 {                                                                       \
 143         name##_SPLAY(head, elm);                                        \
 144         if (SPLAY_RIGHT(elm, field) != NULL) {                          \
 145                 elm = SPLAY_RIGHT(elm, field);                          \
 146                 while (SPLAY_LEFT(elm, field) != NULL) {                \
 147                         elm = SPLAY_LEFT(elm, field);                   \
 148                 }                                                       \
 149         } else                                                          \
 150                 elm = NULL;                                             \
 151         return (elm);                                                   \
 152 }                                                                       \
 153                                                                         \
 154 static __inline struct type *                                           \
 155 name##_SPLAY_MIN_MAX(struct name *head, int val)                        \
 156 {                                                                       \
 157         name##_SPLAY_MINMAX(head, val);                                 \
 158         return (SPLAY_ROOT(head));                                      \
 159 }
 160
 161 /* Main splay operation.
 162  * Moves node close to the key of elm to top
 163  */
 164 #define SPLAY_GENERATE(name, type, field, cmp)                          \
 165 struct type *                                                           \
 166 name##_SPLAY_INSERT(struct name *head, struct type *elm)                \
 167 {                                                                       \
 168     if (SPLAY_EMPTY(head)) {                                            \
 169             SPLAY_LEFT(elm, field) = SPLAY_RIGHT(elm, field) = NULL;    \
 170     } else {                                                            \
 171             int __comp;                                                 \
 172             name##_SPLAY(head, elm);                                    \
 173             __comp = (cmp)(elm, (head)->sph_root);                      \
 174             if(__comp < 0) {                                            \
 175                     SPLAY_LEFT(elm, field) = SPLAY_LEFT((head)->sph_root, field);\
 176                     SPLAY_RIGHT(elm, field) = (head)->sph_root;         \
 177                     SPLAY_LEFT((head)->sph_root, field) = NULL;         \
 178             } else if (__comp > 0) {                                    \
 179                     SPLAY_RIGHT(elm, field) = SPLAY_RIGHT((head)->sph_root, field);\
 180                     SPLAY_LEFT(elm, field) = (head)->sph_root;          \
 181                     SPLAY_RIGHT((head)->sph_root, field) = NULL;        \
 182             } else                                                      \
 183                     return ((head)->sph_root);                          \
 184     }                                                                   \
 185     (head)->sph_root = (elm);                                           \
 186     return (NULL);                                                      \
 187 }                                                                       \
 188                                                                         \
 189 struct type *                                                           \
 190 name##_SPLAY_REMOVE(struct name *head, struct type *elm)                \
 191 {                                                                       \
 192         struct type *__tmp;                                             \
 193         if (SPLAY_EMPTY(head))                                          \
 194                 return (NULL);                                          \
 195         name##_SPLAY(head, elm);                                        \
 196         if ((cmp)(elm, (head)->sph_root) == 0) {                        \
 197                 if (SPLAY_LEFT((head)->sph_root, field) == NULL) {      \
 198                         (head)->sph_root = SPLAY_RIGHT((head)->sph_root, field);\
 199                 } else {                                                \
 200                         __tmp = SPLAY_RIGHT((head)->sph_root, field);   \
 201                         (head)->sph_root = SPLAY_LEFT((head)->sph_root, field);\
 202                         name##_SPLAY(head, elm);                        \
 203                         SPLAY_RIGHT((head)->sph_root, field) = __tmp;   \
 204                 }                                                       \
 205                 return (elm);                                           \
 206         }                                                               \
 207         return (NULL);                                                  \
 208 }                                                                       \
 209                                                                         \
 210 void                                                                    \
 211 name##_SPLAY(struct name *head, struct type *elm)                       \
 212 {                                                                       \
 213         struct type __node, *__left, *__right, *__tmp;                  \
 214         int __comp;                                                     \
 215 \
 216         SPLAY_LEFT(&__node, field) = SPLAY_RIGHT(&__node, field) = NULL;\
 217         __left = __right = &__node;                                     \
 218 \
 219         while ((__comp = (cmp)(elm, (head)->sph_root)) != 0) {          \
 220                 if (__comp < 0) {                                       \
 221                         __tmp = SPLAY_LEFT((head)->sph_root, field);    \
 222                         if (__tmp == NULL)                              \
 223                                 break;                                  \
 224                         if ((cmp)(elm, __tmp) < 0){                     \
 225                                 SPLAY_ROTATE_RIGHT(head, __tmp, field); \
 226                                 if (SPLAY_LEFT((head)->sph_root, field) == NULL)\
 227                                         break;                          \
 228                         }                                               \
 229                         SPLAY_LINKLEFT(head, __right, field);           \
 230                 } else if (__comp > 0) {                                \
 231                         __tmp = SPLAY_RIGHT((head)->sph_root, field);   \
 232                         if (__tmp == NULL)                              \
 233                                 break;                                  \
 234                         if ((cmp)(elm, __tmp) > 0){                     \
 235                                 SPLAY_ROTATE_LEFT(head, __tmp, field);  \
 236                                 if (SPLAY_RIGHT((head)->sph_root, field) == NULL)\
 237                                         break;                          \
 238                         }                                               \
 239                         SPLAY_LINKRIGHT(head, __left, field);           \
 240                 }                                                       \
 241         }                                                               \
 242         SPLAY_ASSEMBLE(head, &__node, __left, __right, field);          \
 243 }                                                                       \
 244                                                                         \
 245 /* Splay with either the minimum or the maximum element                 \
 246  * Used to find minimum or maximum element in tree.                     \
 247  */                                                                     \
 248 void name##_SPLAY_MINMAX(struct name *head, int __comp) \
 249 {                                                                       \
 250         struct type __node, *__left, *__right, *__tmp;                  \
 251 \
 252         SPLAY_LEFT(&__node, field) = SPLAY_RIGHT(&__node, field) = NULL;\
 253         __left = __right = &__node;                                     \
 254 \
 255         while (1) {                                                     \
 256                 if (__comp < 0) {                                       \
 257                         __tmp = SPLAY_LEFT((head)->sph_root, field);    \
 258                         if (__tmp == NULL)                              \
 259                                 break;                                  \
 260                         if (__comp < 0){                                \
 261                                 SPLAY_ROTATE_RIGHT(head, __tmp, field); \
 262                                 if (SPLAY_LEFT((head)->sph_root, field) == NULL)\
 263                                         break;                          \
 264                         }                                               \
 265                         SPLAY_LINKLEFT(head, __right, field);           \
 266                 } else if (__comp > 0) {                                \
 267                         __tmp = SPLAY_RIGHT((head)->sph_root, field);   \
 268                         if (__tmp == NULL)                              \
 269                                 break;                                  \
 270                         if (__comp > 0) {                               \
 271                                 SPLAY_ROTATE_LEFT(head, __tmp, field);  \
 272                                 if (SPLAY_RIGHT((head)->sph_root, field) == NULL)\
 273                                         break;                          \
 274                         }                                               \
 275                         SPLAY_LINKRIGHT(head, __left, field);           \
 276                 }                                                       \
 277         }                                                               \
 278         SPLAY_ASSEMBLE(head, &__node, __left, __right, field);          \
 279 }
 280
 281 #define SPLAY_NEGINF    -1
 282 #define SPLAY_INF       1
 283
 284 #define SPLAY_INSERT(name, x, y)        name##_SPLAY_INSERT(x, y)
 285 #define SPLAY_REMOVE(name, x, y)        name##_SPLAY_REMOVE(x, y)
 286 #define SPLAY_FIND(name, x, y)          name##_SPLAY_FIND(x, y)
 287 #define SPLAY_NEXT(name, x, y)          name##_SPLAY_NEXT(x, y)
 288 #define SPLAY_MIN(name, x)              (SPLAY_EMPTY(x) ? NULL  \
 289                                         : name##_SPLAY_MIN_MAX(x, SPLAY_NEGINF))
 290 #define SPLAY_MAX(name, x)              (SPLAY_EMPTY(x) ? NULL  \
 291                                         : name##_SPLAY_MIN_MAX(x, SPLAY_INF))
 292
 293 #define SPLAY_FOREACH(x, name, head)                                    \
 294         for ((x) = SPLAY_MIN(name, head);                               \
 295              (x) != NULL;                                               \
 296              (x) = SPLAY_NEXT(name, head, x))
 297
 298 /* Macros that define a red-black tree */
 299 #define RB_HEAD(name, type)                                             \
 300 struct name {                                                           \
 301         struct type *rbh_root; /* root of the tree */                   \
 302 }
 303
 304 #define RB_INITIALIZER(root)                                            \
 305         { NULL }
 306
 307 #define RB_INIT(root) do {                                              \
 308         (root)->rbh_root = NULL;                                        \
 309 } while (/*CONSTCOND*/ 0)
 310
 311 #define RB_BLACK        0
 312 #define RB_RED          1
 313 #define RB_ENTRY(type)                                                  \
 314 struct {                                                                \
 315         struct type *rbe_left;          /* left element */              \
 316         struct type *rbe_right;         /* right element */             \
 317         struct type *rbe_parent;        /* parent element */            \
 318         int rbe_color;                  /* node color */                \
 319 }
 320
 321 #define RB_LEFT(elm, field)             (elm)->field.rbe_left
 322 #define RB_RIGHT(elm, field)            (elm)->field.rbe_right
 323 #define RB_PARENT(elm, field)           (elm)->field.rbe_parent
 324 #define RB_COLOR(elm, field)            (elm)->field.rbe_color
 325 #define RB_ROOT(head)                   (head)->rbh_root
 326 #define RB_EMPTY(head)                  (RB_ROOT(head) == NULL)
 327
 328 #define RB_SET(elm, parent, field) do {                                 \
 329         RB_PARENT(elm, field) = parent;                                 \
 330         RB_LEFT(elm, field) = RB_RIGHT(elm, field) = NULL;              \
 331         RB_COLOR(elm, field) = RB_RED;                                  \
 332 } while (/*CONSTCOND*/ 0)
 333
 334 #define RB_SET_BLACKRED(black, red, field) do {                         \
 335         RB_COLOR(black, field) = RB_BLACK;                              \
 336         RB_COLOR(red, field) = RB_RED;                                  \
 337 } while (/*CONSTCOND*/ 0)
 338
 339 #ifndef RB_AUGMENT
 340 #define RB_AUGMENT(x)   do {} while (0)
 341 #endif
 342
 343 #define RB_ROTATE_LEFT(head, elm, tmp, field) do {                      \
 344         (tmp) = RB_RIGHT(elm, field);                                   \
 345         if ((RB_RIGHT(elm, field) = RB_LEFT(tmp, field)) != NULL) {     \
 346                 RB_PARENT(RB_LEFT(tmp, field), field) = (elm);          \
 347         }                                                               \
 348         RB_AUGMENT(elm);                                                \
 349         if ((RB_PARENT(tmp, field) = RB_PARENT(elm, field)) != NULL) {  \
 350                 if ((elm) == RB_LEFT(RB_PARENT(elm, field), field))     \
 351                         RB_LEFT(RB_PARENT(elm, field), field) = (tmp);  \
 352                 else                                                    \
 353                         RB_RIGHT(RB_PARENT(elm, field), field) = (tmp); \
 354         } else                                                          \
 355                 (head)->rbh_root = (tmp);                               \
 356         RB_LEFT(tmp, field) = (elm);                                    \
 357         RB_PARENT(elm, field) = (tmp);                                  \
 358         RB_AUGMENT(tmp);                                                \
 359         if ((RB_PARENT(tmp, field)))                                    \
 360                 RB_AUGMENT(RB_PARENT(tmp, field));                      \
 361 } while (/*CONSTCOND*/ 0)
 362
 363 #define RB_ROTATE_RIGHT(head, elm, tmp, field) do {                     \
 364         (tmp) = RB_LEFT(elm, field);                                    \
 365         if ((RB_LEFT(elm, field) = RB_RIGHT(tmp, field)) != NULL) {     \
 366                 RB_PARENT(RB_RIGHT(tmp, field), field) = (elm);         \
 367         }                                                               \
 368         RB_AUGMENT(elm);                                                \
 369         if ((RB_PARENT(tmp, field) = RB_PARENT(elm, field)) != NULL) {  \
 370                 if ((elm) == RB_LEFT(RB_PARENT(elm, field), field))     \
 371                         RB_LEFT(RB_PARENT(elm, field), field) = (tmp);  \
 372                 else                                                    \
 373                         RB_RIGHT(RB_PARENT(elm, field), field) = (tmp); \
 374         } else                                                          \
 375                 (head)->rbh_root = (tmp);                               \
 376         RB_RIGHT(tmp, field) = (elm);                                   \
 377         RB_PARENT(elm, field) = (tmp);                                  \
 378         RB_AUGMENT(tmp);                                                \
 379         if ((RB_PARENT(tmp, field)))                                    \
 380                 RB_AUGMENT(RB_PARENT(tmp, field));                      \
 381 } while (/*CONSTCOND*/ 0)
 382
 383 /* Generates prototypes and inline functions */
 384 #define RB_PROTOTYPE(name, type, field, cmp)                            \
 385         RB_PROTOTYPE_INTERNAL(name, type, field, cmp,)
 386 #define RB_PROTOTYPE_STATIC(name, type, field, cmp)                     \
 387         RB_PROTOTYPE_INTERNAL(name, type, field, cmp, __unused static)
 388 #define RB_PROTOTYPE_INTERNAL(name, type, field, cmp, attr)             \
 389         RB_PROTOTYPE_INSERT_COLOR(name, type, attr);                    \
 390         RB_PROTOTYPE_REMOVE_COLOR(name, type, attr);                    \
 391         RB_PROTOTYPE_INSERT(name, type, attr);                          \
 392         RB_PROTOTYPE_REMOVE(name, type, attr);                          \
 393         RB_PROTOTYPE_FIND(name, type, attr);                            \
 394         RB_PROTOTYPE_NFIND(name, type, attr);                           \
 395         RB_PROTOTYPE_NEXT(name, type, attr);                            \
 396         RB_PROTOTYPE_PREV(name, type, attr);                            \
 397         RB_PROTOTYPE_MINMAX(name, type, attr);
 398 #define RB_PROTOTYPE_INSERT_COLOR(name, type, attr)                     \
 399         attr void name##_RB_INSERT_COLOR(struct name *, struct type *)
 400 #define RB_PROTOTYPE_REMOVE_COLOR(name, type, attr)                     \
 401         attr void name##_RB_REMOVE_COLOR(struct name *, struct type *, struct type *)
 402 #define RB_PROTOTYPE_REMOVE(name, type, attr)                           \
 403         attr struct type *name##_RB_REMOVE(struct name *, struct type *)
 404 #define RB_PROTOTYPE_INSERT(name, type, attr)                           \
 405         attr struct type *name##_RB_INSERT(struct name *, struct type *)
 406 #define RB_PROTOTYPE_FIND(name, type, attr)                             \
 407         attr struct type *name##_RB_FIND(struct name *, struct type *)
 408 #define RB_PROTOTYPE_NFIND(name, type, attr)                            \
 409         attr struct type *name##_RB_NFIND(struct name *, struct type *)
 410 #define RB_PROTOTYPE_NEXT(name, type, attr)                             \
 411         attr struct type *name##_RB_NEXT(struct type *)
 412 #define RB_PROTOTYPE_PREV(name, type, attr)                             \
 413         attr struct type *name##_RB_PREV(struct type *)
 414 #define RB_PROTOTYPE_MINMAX(name, type, attr)                           \
 415         attr struct type *name##_RB_MINMAX(struct name *, int)
 416
 417 /* Main rb operation.
 418  * Moves node close to the key of elm to top
 419  */
 420 #define RB_GENERATE(name, type, field, cmp)                             \
 421         RB_GENERATE_INTERNAL(name, type, field, cmp,)
 422 #define RB_GENERATE_STATIC(name, type, field, cmp)                      \
 423         RB_GENERATE_INTERNAL(name, type, field, cmp, __unused static)
 424 #define RB_GENERATE_INTERNAL(name, type, field, cmp, attr)              \
 425         RB_GENERATE_INSERT_COLOR(name, type, field, attr)               \
 426         RB_GENERATE_REMOVE_COLOR(name, type, field, attr)               \
 427         RB_GENERATE_INSERT(name, type, field, cmp, attr)                \
 428         RB_GENERATE_REMOVE(name, type, field, attr)                     \
 429         RB_GENERATE_FIND(name, type, field, cmp, attr)                  \
 430         RB_GENERATE_NFIND(name, type, field, cmp, attr)                 \
 431         RB_GENERATE_NEXT(name, type, field, attr)                       \
 432         RB_GENERATE_PREV(name, type, field, attr)                       \
 433         RB_GENERATE_MINMAX(name, type, field, attr)
 434
 435 #define RB_GENERATE_INSERT_COLOR(name, type, field, attr)               \
 436 attr void                                                               \
 437 name##_RB_INSERT_COLOR(struct name *head, struct type *elm)             \
 438 {                                                                       \
 439         struct type *parent, *gparent, *tmp;                            \
 440         while ((parent = RB_PARENT(elm, field)) != NULL &&              \
 441             RB_COLOR(parent, field) == RB_RED) {                        \
 442                 gparent = RB_PARENT(parent, field);                     \
 443                 if (parent == RB_LEFT(gparent, field)) {                \
 444                         tmp = RB_RIGHT(gparent, field);                 \
 445                         if (tmp && RB_COLOR(tmp, field) == RB_RED) {    \
 446                                 RB_COLOR(tmp, field) = RB_BLACK;        \
 447                                 RB_SET_BLACKRED(parent, gparent, field);\
 448                                 elm = gparent;                          \
 449                                 continue;                               \
 450                         }                                               \
 451                         if (RB_RIGHT(parent, field) == elm) {           \
 452                                 RB_ROTATE_LEFT(head, parent, tmp, field);\
 453                                 tmp = parent;                           \
 454                                 parent = elm;                           \
 455                                 elm = tmp;                              \
 456                         }                                               \
 457                         RB_SET_BLACKRED(parent, gparent, field);        \
 458                         RB_ROTATE_RIGHT(head, gparent, tmp, field);     \
 459                 } else {                                                \
 460                         tmp = RB_LEFT(gparent, field);                  \
 461                         if (tmp && RB_COLOR(tmp, field) == RB_RED) {    \
 462                                 RB_COLOR(tmp, field) = RB_BLACK;        \
 463                                 RB_SET_BLACKRED(parent, gparent, field);\
 464                                 elm = gparent;                          \
 465                                 continue;                               \
 466                         }                                               \
 467                         if (RB_LEFT(parent, field) == elm) {            \
 468                                 RB_ROTATE_RIGHT(head, parent, tmp, field);\
 469                                 tmp = parent;                           \
 470                                 parent = elm;                           \
 471                                 elm = tmp;                              \
 472                         }                                               \
 473                         RB_SET_BLACKRED(parent, gparent, field);        \
 474                         RB_ROTATE_LEFT(head, gparent, tmp, field);      \
 475                 }                                                       \
 476         }                                                               \
 477         RB_COLOR(head->rbh_root, field) = RB_BLACK;                     \
 478 }
 479
 480 #define RB_GENERATE_REMOVE_COLOR(name, type, field, attr)               \
 481 attr void                                                               \
 482 name##_RB_REMOVE_COLOR(struct name *head, struct type *parent, struct type *elm) \
 483 {                                                                       \
 484         struct type *tmp;                                               \
 485         while ((elm == NULL || RB_COLOR(elm, field) == RB_BLACK) &&     \
 486             elm != RB_ROOT(head)) {                                     \
 487                 if (RB_LEFT(parent, field) == elm) {                    \
 488                         tmp = RB_RIGHT(parent, field);                  \
 489                         if (RB_COLOR(tmp, field) == RB_RED) {           \
 490                                 RB_SET_BLACKRED(tmp, parent, field);    \
 491                                 RB_ROTATE_LEFT(head, parent, tmp, field);\
 492                                 tmp = RB_RIGHT(parent, field);          \
 493                         }                                               \
 494                         if ((RB_LEFT(tmp, field) == NULL ||             \
 495                             RB_COLOR(RB_LEFT(tmp, field), field) == RB_BLACK) &&\
 496                             (RB_RIGHT(tmp, field) == NULL ||            \
 497                             RB_COLOR(RB_RIGHT(tmp, field), field) == RB_BLACK)) {\
 498                                 RB_COLOR(tmp, field) = RB_RED;          \
 499                                 elm = parent;                           \
 500                                 parent = RB_PARENT(elm, field);         \
 501                         } else {                                        \
 502                                 if (RB_RIGHT(tmp, field) == NULL ||     \
 503                                     RB_COLOR(RB_RIGHT(tmp, field), field) == RB_BLACK) {\
 504                                         struct type *oleft;             \
 505                                         if ((oleft = RB_LEFT(tmp, field)) \
 506                                             != NULL)                    \
 507                                                 RB_COLOR(oleft, field) = RB_BLACK;\
 508                                         RB_COLOR(tmp, field) = RB_RED;  \
 509                                         RB_ROTATE_RIGHT(head, tmp, oleft, field);\
 510                                         tmp = RB_RIGHT(parent, field);  \
 511                                 }                                       \
 512                                 RB_COLOR(tmp, field) = RB_COLOR(parent, field);\
 513                                 RB_COLOR(parent, field) = RB_BLACK;     \
 514                                 if (RB_RIGHT(tmp, field))               \
 515                                         RB_COLOR(RB_RIGHT(tmp, field), field) = RB_BLACK;\
 516                                 RB_ROTATE_LEFT(head, parent, tmp, field);\
 517                                 elm = RB_ROOT(head);                    \
 518                                 break;                                  \
 519                         }                                               \
 520                 } else {                                                \
 521                         tmp = RB_LEFT(parent, field);                   \
 522                         if (RB_COLOR(tmp, field) == RB_RED) {           \
 523                                 RB_SET_BLACKRED(tmp, parent, field);    \
 524                                 RB_ROTATE_RIGHT(head, parent, tmp, field);\
 525                                 tmp = RB_LEFT(parent, field);           \
 526                         }                                               \
 527                         if ((RB_LEFT(tmp, field) == NULL ||             \
 528                             RB_COLOR(RB_LEFT(tmp, field), field) == RB_BLACK) &&\
 529                             (RB_RIGHT(tmp, field) == NULL ||            \
 530                             RB_COLOR(RB_RIGHT(tmp, field), field) == RB_BLACK)) {\
 531                                 RB_COLOR(tmp, field) = RB_RED;          \
 532                                 elm = parent;                           \
 533                                 parent = RB_PARENT(elm, field);         \
 534                         } else {                                        \
 535                                 if (RB_LEFT(tmp, field) == NULL ||      \
 536                                     RB_COLOR(RB_LEFT(tmp, field), field) == RB_BLACK) {\
 537                                         struct type *oright;            \
 538                                         if ((oright = RB_RIGHT(tmp, field)) \
 539                                             != NULL)                    \
 540                                                 RB_COLOR(oright, field) = RB_BLACK;\
 541                                         RB_COLOR(tmp, field) = RB_RED;  \
 542                                         RB_ROTATE_LEFT(head, tmp, oright, field);\
 543                                         tmp = RB_LEFT(parent, field);   \
 544                                 }                                       \
 545                                 RB_COLOR(tmp, field) = RB_COLOR(parent, field);\
 546                                 RB_COLOR(parent, field) = RB_BLACK;     \
 547                                 if (RB_LEFT(tmp, field))                \
 548                                         RB_COLOR(RB_LEFT(tmp, field), field) = RB_BLACK;\
 549                                 RB_ROTATE_RIGHT(head, parent, tmp, field);\
 550                                 elm = RB_ROOT(head);                    \
 551                                 break;                                  \
 552                         }                                               \
 553                 }                                                       \
 554         }                                                               \
 555         if (elm)                                                        \
 556                 RB_COLOR(elm, field) = RB_BLACK;                        \
 557 }
 558
 559 #define RB_GENERATE_REMOVE(name, type, field, attr)                     \
 560 attr struct type *                                                      \
 561 name##_RB_REMOVE(struct name *head, struct type *elm)                   \
 562 {                                                                       \
 563         struct type *child, *parent, *old = elm;                        \
 564         int color;                                                      \
 565         if (RB_LEFT(elm, field) == NULL)                                \
 566                 child = RB_RIGHT(elm, field);                           \
 567         else if (RB_RIGHT(elm, field) == NULL)                          \
 568                 child = RB_LEFT(elm, field);                            \
 569         else {                                                          \
 570                 struct type *left;                                      \
 571                 elm = RB_RIGHT(elm, field);                             \
 572                 while ((left = RB_LEFT(elm, field)) != NULL)            \
 573                         elm = left;                                     \
 574                 child = RB_RIGHT(elm, field);                           \
 575                 parent = RB_PARENT(elm, field);                         \
 576                 color = RB_COLOR(elm, field);                           \
 577                 if (child)                                              \
 578                         RB_PARENT(child, field) = parent;               \
 579                 if (parent) {                                           \
 580                         if (RB_LEFT(parent, field) == elm)              \
 581                                 RB_LEFT(parent, field) = child;         \
 582                         else                                            \
 583                                 RB_RIGHT(parent, field) = child;        \
 584                         RB_AUGMENT(parent);                             \
 585                 } else                                                  \
 586                         RB_ROOT(head) = child;                          \
 587                 if (RB_PARENT(elm, field) == old)                       \
 588                         parent = elm;                                   \
 589                 (elm)->field = (old)->field;                            \
 590                 if (RB_PARENT(old, field)) {                            \
 591                         if (RB_LEFT(RB_PARENT(old, field), field) == old)\
 592                                 RB_LEFT(RB_PARENT(old, field), field) = elm;\
 593                         else                                            \
 594                                 RB_RIGHT(RB_PARENT(old, field), field) = elm;\
 595                         RB_AUGMENT(RB_PARENT(old, field));              \
 596                 } else                                                  \
 597                         RB_ROOT(head) = elm;                            \
 598                 RB_PARENT(RB_LEFT(old, field), field) = elm;            \
 599                 if (RB_RIGHT(old, field))                               \
 600                         RB_PARENT(RB_RIGHT(old, field), field) = elm;   \
 601                 if (parent) {                                           \
 602                         left = parent;                                  \
 603                         do {                                            \
 604                                 RB_AUGMENT(left);                       \
 605                         } while ((left = RB_PARENT(left, field)) != NULL); \
 606                 }                                                       \
 607                 goto color;                                             \
 608         }                                                               \
 609         parent = RB_PARENT(elm, field);                                 \
 610         color = RB_COLOR(elm, field);                                   \
 611         if (child)                                                      \
 612                 RB_PARENT(child, field) = parent;                       \
 613         if (parent) {                                                   \
 614                 if (RB_LEFT(parent, field) == elm)                      \
 615                         RB_LEFT(parent, field) = child;                 \
 616                 else                                                    \
 617                         RB_RIGHT(parent, field) = child;                \
 618                 RB_AUGMENT(parent);                                     \
 619         } else                                                          \
 620                 RB_ROOT(head) = child;                                  \
 621 color:                                                                  \
 622         if (color == RB_BLACK)                                          \
 623                 name##_RB_REMOVE_COLOR(head, parent, child);            \
 624         return (old);                                                   \
 625 }                                                                       \
 626
 627 #define RB_GENERATE_INSERT(name, type, field, cmp, attr)                \
 628 /* Inserts a node into the RB tree */                                   \
 629 attr struct type *                                                      \
 630 name##_RB_INSERT(struct name *head, struct type *elm)                   \
 631 {                                                                       \
 632         struct type *tmp;                                               \
 633         struct type *parent = NULL;                                     \
 634         int comp = 0;                                                   \
 635         tmp = RB_ROOT(head);                                            \
 636         while (tmp) {                                                   \
 637                 parent = tmp;                                           \
 638                 comp = (cmp)(elm, parent);                              \
 639                 if (comp < 0)                                           \
 640                         tmp = RB_LEFT(tmp, field);                      \
 641                 else if (comp > 0)                                      \
 642                         tmp = RB_RIGHT(tmp, field);                     \
 643                 else                                                    \
 644                         return (tmp);                                   \
 645         }                                                               \
 646         RB_SET(elm, parent, field);                                     \
 647         if (parent != NULL) {                                           \
 648                 if (comp < 0)                                           \
 649                         RB_LEFT(parent, field) = elm;                   \
 650                 else                                                    \
 651                         RB_RIGHT(parent, field) = elm;                  \
 652                 RB_AUGMENT(parent);                                     \
 653         } else                                                          \
 654                 RB_ROOT(head) = elm;                                    \
 655         name##_RB_INSERT_COLOR(head, elm);                              \
 656         return (NULL);                                                  \
 657 }
 658
 659 #define RB_GENERATE_FIND(name, type, field, cmp, attr)                  \
 660 /* Finds the node with the same key as elm */                           \
 661 attr struct type *                                                      \
 662 name##_RB_FIND(struct name *head, struct type *elm)                     \
 663 {                                                                       \
 664         struct type *tmp = RB_ROOT(head);                               \
 665         int comp;                                                       \
 666         while (tmp) {                                                   \
 667                 comp = cmp(elm, tmp);                                   \
 668                 if (comp < 0)                                           \
 669                         tmp = RB_LEFT(tmp, field);                      \
 670                 else if (comp > 0)                                      \
 671                         tmp = RB_RIGHT(tmp, field);                     \
 672                 else                                                    \
 673                         return (tmp);                                   \
 674         }                                                               \
 675         return (NULL);                                                  \
 676 }
 677
 678 #define RB_GENERATE_NFIND(name, type, field, cmp, attr)                 \
 679 /* Finds the first node greater than or equal to the search key */      \
 680 attr struct type *                                                      \
 681 name##_RB_NFIND(struct name *head, struct type *elm)                    \
 682 {                                                                       \
 683         struct type *tmp = RB_ROOT(head);                               \
 684         struct type *res = NULL;                                        \
 685         int comp;                                                       \
 686         while (tmp) {                                                   \
 687                 comp = cmp(elm, tmp);                                   \
 688                 if (comp < 0) {                                         \
 689                         res = tmp;                                      \
 690                         tmp = RB_LEFT(tmp, field);                      \
 691                 }                                                       \
 692                 else if (comp > 0)                                      \
 693                         tmp = RB_RIGHT(tmp, field);                     \
 694                 else                                                    \
 695                         return (tmp);                                   \
 696         }                                                               \
 697         return (res);                                                   \
 698 }
 699
 700 #define RB_GENERATE_NEXT(name, type, field, attr)                       \
 701 /* ARGSUSED */                                                          \
 702 attr struct type *                                                      \
 703 name##_RB_NEXT(struct type *elm)                                        \
 704 {                                                                       \
 705         if (RB_RIGHT(elm, field)) {                                     \
 706                 elm = RB_RIGHT(elm, field);                             \
 707                 while (RB_LEFT(elm, field))                             \
 708                         elm = RB_LEFT(elm, field);                      \
 709         } else {                                                        \
 710                 if (RB_PARENT(elm, field) &&                            \
 711                     (elm == RB_LEFT(RB_PARENT(elm, field), field)))     \
 712                         elm = RB_PARENT(elm, field);                    \
 713                 else {                                                  \
 714                         while (RB_PARENT(elm, field) &&                 \
 715                             (elm == RB_RIGHT(RB_PARENT(elm, field), field)))\
 716                                 elm = RB_PARENT(elm, field);            \
 717                         elm = RB_PARENT(elm, field);                    \
 718                 }                                                       \
 719         }                                                               \
 720         return (elm);                                                   \
 721 }
 722
 723 #define RB_GENERATE_PREV(name, type, field, attr)                       \
 724 /* ARGSUSED */                                                          \
 725 attr struct type *                                                      \
 726 name##_RB_PREV(struct type *elm)                                        \
 727 {                                                                       \
 728         if (RB_LEFT(elm, field)) {                                      \
 729                 elm = RB_LEFT(elm, field);                              \
 730                 while (RB_RIGHT(elm, field))                            \
 731                         elm = RB_RIGHT(elm, field);                     \
 732         } else {                                                        \
 733                 if (RB_PARENT(elm, field) &&                            \
 734                     (elm == RB_RIGHT(RB_PARENT(elm, field), field)))    \
 735                         elm = RB_PARENT(elm, field);                    \
 736                 else {                                                  \
 737                         while (RB_PARENT(elm, field) &&                 \
 738                             (elm == RB_LEFT(RB_PARENT(elm, field), field)))\
 739                                 elm = RB_PARENT(elm, field);            \
 740                         elm = RB_PARENT(elm, field);                    \
 741                 }                                                       \
 742         }                                                               \
 743         return (elm);                                                   \
 744 }
 745
 746 #define RB_GENERATE_MINMAX(name, type, field, attr)                     \
 747 attr struct type *                                                      \
 748 name##_RB_MINMAX(struct name *head, int val)                            \
 749 {                                                                       \
 750         struct type *tmp = RB_ROOT(head);                               \
 751         struct type *parent = NULL;                                     \
 752         while (tmp) {                                                   \
 753                 parent = tmp;                                           \
 754                 if (val < 0)                                            \
 755                         tmp = RB_LEFT(tmp, field);                      \
 756                 else                                                    \
 757                         tmp = RB_RIGHT(tmp, field);                     \
 758         }                                                               \
 759         return (parent);                                                \
 760 }
 761
 762 #define RB_NEGINF       -1
 763 #define RB_INF  1
 764
 765 #define RB_INSERT(name, x, y)   name##_RB_INSERT(x, y)
 766 #define RB_REMOVE(name, x, y)   name##_RB_REMOVE(x, y)
 767 #define RB_FIND(name, x, y)     name##_RB_FIND(x, y)
 768 #define RB_NFIND(name, x, y)    name##_RB_NFIND(x, y)
 769 #define RB_NEXT(name, x, y)     name##_RB_NEXT(y)
 770 #define RB_PREV(name, x, y)     name##_RB_PREV(y)
 771 #define RB_MIN(name, x)         name##_RB_MINMAX(x, RB_NEGINF)
 772 #define RB_MAX(name, x)         name##_RB_MINMAX(x, RB_INF)
 773
 774 #define RB_FOREACH(x, name, head)                                       \
 775         for ((x) = RB_MIN(name, head);                                  \
 776              (x) != NULL;                                               \
 777              (x) = name##_RB_NEXT(x))
 778
 779 #define RB_FOREACH_FROM(x, name, y)                                     \
 780         for ((x) = (y);                                                 \
 781             ((x) != NULL) && ((y) = name##_RB_NEXT(x), (x) != NULL);    \
 782              (x) = (y))
 783
 784 #define RB_FOREACH_SAFE(x, name, head, y)                               \
 785         for ((x) = RB_MIN(name, head);                                  \
 786             ((x) != NULL) && ((y) = name##_RB_NEXT(x), (x) != NULL);    \
 787              (x) = (y))
 788
 789 #define RB_FOREACH_REVERSE(x, name, head)                               \
 790         for ((x) = RB_MAX(name, head);                                  \
 791              (x) != NULL;                                               \
 792              (x) = name##_RB_PREV(x))
 793
 794 #define RB_FOREACH_REVERSE_FROM(x, name, y)                             \
 795         for ((x) = (y);                                                 \
 796             ((x) != NULL) && ((y) = name##_RB_PREV(x), (x) != NULL);    \
 797              (x) = (y))
 798
 799 #define RB_FOREACH_REVERSE_SAFE(x, name, head, y)                       \
 800         for ((x) = RB_MAX(name, head);                                  \
 801             ((x) != NULL) && ((y) = name##_RB_PREV(x), (x) != NULL);    \
 802              (x) = (y))
 803
 804 #endif  /* _SYS_TREE_H_ */