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