/* libavl - library for manipulation of binary trees. Copyright (C) 1998-2002, 2004 Free Software Foundation, Inc. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. The author may be contacted at on the Internet, or write to Ben Pfaff, Stanford University, Computer Science Dept., 353 Serra Mall, Stanford CA 94305, USA. */ #include #include #include #include "rtrb.h" /* Creates and returns a new table with comparison function |compare| using parameter |param| and memory allocator |allocator|. Returns |NULL| if memory allocation failed. */ struct rtrb_table * rtrb_create (rtrb_comparison_func *compare, void *param, struct libavl_allocator *allocator) { struct rtrb_table *tree; assert (compare != NULL); if (allocator == NULL) allocator = &rtrb_allocator_default; tree = allocator->libavl_malloc (allocator, sizeof *tree); if (tree == NULL) return NULL; tree->rtrb_root = NULL; tree->rtrb_compare = compare; tree->rtrb_param = param; tree->rtrb_alloc = allocator; tree->rtrb_count = 0; return tree; } /* Search |tree| for an item matching |item|, and return it if found. Otherwise return |NULL|. */ void * rtrb_find (const struct rtrb_table *tree, const void *item) { const struct rtrb_node *p; int dir; assert (tree != NULL && item != NULL); if (tree->rtrb_root == NULL) return NULL; for (p = tree->rtrb_root; ; p = p->rtrb_link[dir]) { int cmp = tree->rtrb_compare (item, p->rtrb_data, tree->rtrb_param); if (cmp == 0) return p->rtrb_data; dir = cmp > 0; if (dir == 0) { if (p->rtrb_link[0] == NULL) return NULL; } else /* |dir == 1| */ { if (p->rtrb_rtag == RTRB_THREAD) return NULL; } } } /* Inserts |item| into |tree| and returns a pointer to |item|'s address. If a duplicate item is found in the tree, returns a pointer to the duplicate without inserting |item|. Returns |NULL| in case of memory allocation failure. */ void ** rtrb_probe (struct rtrb_table *tree, void *item) { struct rtrb_node *pa[RTRB_MAX_HEIGHT]; /* Nodes on stack. */ unsigned char da[RTRB_MAX_HEIGHT]; /* Directions moved from stack nodes. */ int k; /* Stack height. */ struct rtrb_node *p; /* Current node in search. */ struct rtrb_node *n; /* New node. */ int dir; /* Side of |p| on which |p| is located. */ assert (tree != NULL && item != NULL); da[0] = 0; pa[0] = (struct rtrb_node *) &tree->rtrb_root; k = 1; if (tree->rtrb_root != NULL) for (p = tree->rtrb_root; ; p = p->rtrb_link[dir]) { int cmp = tree->rtrb_compare (item, p->rtrb_data, tree->rtrb_param); if (cmp == 0) return &p->rtrb_data; pa[k] = p; da[k++] = dir = cmp > 0; if (dir == 0) { if (p->rtrb_link[0] == NULL) break; } else /* |dir == 1| */ { if (p->rtrb_rtag == RTRB_THREAD) break; } } else { p = (struct rtrb_node *) &tree->rtrb_root; dir = 0; } n = tree->rtrb_alloc->libavl_malloc (tree->rtrb_alloc, sizeof *n); if (n == NULL) return NULL; tree->rtrb_count++; n->rtrb_data = item; n->rtrb_link[0] = NULL; if (dir == 0) { if (tree->rtrb_root != NULL) n->rtrb_link[1] = p; else n->rtrb_link[1] = NULL; } else /* |dir == 1| */ { p->rtrb_rtag = RTRB_CHILD; n->rtrb_link[1] = p->rtrb_link[1]; } n->rtrb_rtag = RTRB_THREAD; n->rtrb_color = RTRB_RED; p->rtrb_link[dir] = n; while (k >= 3 && pa[k - 1]->rtrb_color == RTRB_RED) { if (da[k - 2] == 0) { struct rtrb_node *y = pa[k - 2]->rtrb_link[1]; if (pa[k - 2]->rtrb_rtag == RTRB_CHILD && y->rtrb_color == RTRB_RED) { pa[k - 1]->rtrb_color = y->rtrb_color = RTRB_BLACK; pa[k - 2]->rtrb_color = RTRB_RED; k -= 2; } else { struct rtrb_node *x; if (da[k - 1] == 0) y = pa[k - 1]; else { x = pa[k - 1]; y = x->rtrb_link[1]; x->rtrb_link[1] = y->rtrb_link[0]; y->rtrb_link[0] = x; pa[k - 2]->rtrb_link[0] = y; if (x->rtrb_link[1] == NULL) { x->rtrb_rtag = RTRB_THREAD; x->rtrb_link[1] = y; } } x = pa[k - 2]; x->rtrb_color = RTRB_RED; y->rtrb_color = RTRB_BLACK; x->rtrb_link[0] = y->rtrb_link[1]; y->rtrb_link[1] = x; pa[k - 3]->rtrb_link[da[k - 3]] = y; if (y->rtrb_rtag == RTRB_THREAD) { y->rtrb_rtag = RTRB_CHILD; x->rtrb_link[0] = NULL; } break; } } else { struct rtrb_node *y = pa[k - 2]->rtrb_link[0]; if (pa[k - 2]->rtrb_link[0] != NULL && y->rtrb_color == RTRB_RED) { pa[k - 1]->rtrb_color = y->rtrb_color = RTRB_BLACK; pa[k - 2]->rtrb_color = RTRB_RED; k -= 2; } else { struct rtrb_node *x; if (da[k - 1] == 1) y = pa[k - 1]; else { x = pa[k - 1]; y = x->rtrb_link[0]; x->rtrb_link[0] = y->rtrb_link[1]; y->rtrb_link[1] = x; pa[k - 2]->rtrb_link[1] = y; if (y->rtrb_rtag == RTRB_THREAD) { y->rtrb_rtag = RTRB_CHILD; x->rtrb_link[0] = NULL; } } x = pa[k - 2]; x->rtrb_color = RTRB_RED; y->rtrb_color = RTRB_BLACK; x->rtrb_link[1] = y->rtrb_link[0]; y->rtrb_link[0] = x; pa[k - 3]->rtrb_link[da[k - 3]] = y; if (x->rtrb_link[1] == NULL) { x->rtrb_rtag = RTRB_THREAD; x->rtrb_link[1] = y; } break; } } } tree->rtrb_root->rtrb_color = RTRB_BLACK; return &n->rtrb_data; } /* Inserts |item| into |table|. Returns |NULL| if |item| was successfully inserted or if a memory allocation error occurred. Otherwise, returns the duplicate item. */ void * rtrb_insert (struct rtrb_table *table, void *item) { void **p = rtrb_probe (table, item); return p == NULL || *p == item ? NULL : *p; } /* Inserts |item| into |table|, replacing any duplicate item. Returns |NULL| if |item| was inserted without replacing a duplicate, or if a memory allocation error occurred. Otherwise, returns the item that was replaced. */ void * rtrb_replace (struct rtrb_table *table, void *item) { void **p = rtrb_probe (table, item); if (p == NULL || *p == item) return NULL; else { void *r = *p; *p = item; return r; } } /* Deletes from |tree| and returns an item matching |item|. Returns a null pointer if no matching item found. */ void * rtrb_delete (struct rtrb_table *tree, const void *item) { struct rtrb_node *pa[RTRB_MAX_HEIGHT]; /* Nodes on stack. */ unsigned char da[RTRB_MAX_HEIGHT]; /* Directions moved from stack nodes. */ int k; /* Stack height. */ struct rtrb_node *p; assert (tree != NULL && item != NULL); k = 1; da[0] = 0; pa[0] = (struct rtrb_node *) &tree->rtrb_root; p = tree->rtrb_root; if (p == NULL) return NULL; for (;;) { int cmp, dir; cmp = tree->rtrb_compare (item, p->rtrb_data, tree->rtrb_param); if (cmp == 0) break; dir = cmp > 0; if (dir == 0) { if (p->rtrb_link[0] == NULL) return NULL; } else /* |dir == 1| */ { if (p->rtrb_rtag == RTRB_THREAD) return NULL; } pa[k] = p; da[k++] = dir; p = p->rtrb_link[dir]; } tree->rtrb_count--; item = p->rtrb_data; if (p->rtrb_link[0] == NULL) { if (p->rtrb_rtag == RTRB_CHILD) { pa[k - 1]->rtrb_link[da[k - 1]] = p->rtrb_link[1]; } else { pa[k - 1]->rtrb_link[da[k - 1]] = p->rtrb_link[da[k - 1]]; if (da[k - 1] == 1) pa[k - 1]->rtrb_rtag = RTRB_THREAD; } } else { enum rtrb_color t; struct rtrb_node *r = p->rtrb_link[0]; if (r->rtrb_rtag == RTRB_THREAD) { r->rtrb_link[1] = p->rtrb_link[1]; r->rtrb_rtag = p->rtrb_rtag; t = r->rtrb_color; r->rtrb_color = p->rtrb_color; p->rtrb_color = t; pa[k - 1]->rtrb_link[da[k - 1]] = r; da[k] = 0; pa[k++] = r; } else { struct rtrb_node *s; int j = k++; for (;;) { da[k] = 1; pa[k++] = r; s = r->rtrb_link[1]; if (s->rtrb_rtag == RTRB_THREAD) break; r = s; } da[j] = 0; pa[j] = pa[j - 1]->rtrb_link[da[j - 1]] = s; if (s->rtrb_link[0] != NULL) r->rtrb_link[1] = s->rtrb_link[0]; else { r->rtrb_rtag = RTRB_THREAD; r->rtrb_link[1] = s; } s->rtrb_link[0] = p->rtrb_link[0]; s->rtrb_link[1] = p->rtrb_link[1]; s->rtrb_rtag = p->rtrb_rtag; t = s->rtrb_color; s->rtrb_color = p->rtrb_color; p->rtrb_color = t; } } if (p->rtrb_color == RTRB_BLACK) { for (; k > 1; k--) { struct rtrb_node *x; if (da[k - 1] == 0 || pa[k - 1]->rtrb_rtag == RTRB_CHILD) x = pa[k - 1]->rtrb_link[da[k - 1]]; else x = NULL; if (x != NULL && x->rtrb_color == RTRB_RED) { x->rtrb_color = RTRB_BLACK; break; } if (da[k - 1] == 0) { struct rtrb_node *w = pa[k - 1]->rtrb_link[1]; if (w->rtrb_color == RTRB_RED) { w->rtrb_color = RTRB_BLACK; pa[k - 1]->rtrb_color = RTRB_RED; pa[k - 1]->rtrb_link[1] = w->rtrb_link[0]; w->rtrb_link[0] = pa[k - 1]; pa[k - 2]->rtrb_link[da[k - 2]] = w; pa[k] = pa[k - 1]; da[k] = 0; pa[k - 1] = w; k++; w = pa[k - 1]->rtrb_link[1]; } if ((w->rtrb_link[0] == NULL || w->rtrb_link[0]->rtrb_color == RTRB_BLACK) && (w->rtrb_rtag == RTRB_THREAD || w->rtrb_link[1]->rtrb_color == RTRB_BLACK)) { w->rtrb_color = RTRB_RED; } else { if (w->rtrb_rtag == RTRB_THREAD || w->rtrb_link[1]->rtrb_color == RTRB_BLACK) { struct rtrb_node *y = w->rtrb_link[0]; y->rtrb_color = RTRB_BLACK; w->rtrb_color = RTRB_RED; w->rtrb_link[0] = y->rtrb_link[1]; y->rtrb_link[1] = w; w = pa[k - 1]->rtrb_link[1] = y; if (w->rtrb_rtag == RTRB_THREAD) { w->rtrb_rtag = RTRB_CHILD; w->rtrb_link[1]->rtrb_link[0] = NULL; } } w->rtrb_color = pa[k - 1]->rtrb_color; pa[k - 1]->rtrb_color = RTRB_BLACK; w->rtrb_link[1]->rtrb_color = RTRB_BLACK; pa[k - 1]->rtrb_link[1] = w->rtrb_link[0]; w->rtrb_link[0] = pa[k - 1]; pa[k - 2]->rtrb_link[da[k - 2]] = w; if (w->rtrb_link[0]->rtrb_link[1] == NULL) { w->rtrb_link[0]->rtrb_rtag = RTRB_THREAD; w->rtrb_link[0]->rtrb_link[1] = w; } break; } } else { struct rtrb_node *w = pa[k - 1]->rtrb_link[0]; if (w->rtrb_color == RTRB_RED) { w->rtrb_color = RTRB_BLACK; pa[k - 1]->rtrb_color = RTRB_RED; pa[k - 1]->rtrb_link[0] = w->rtrb_link[1]; w->rtrb_link[1] = pa[k - 1]; pa[k - 2]->rtrb_link[da[k - 2]] = w; pa[k] = pa[k - 1]; da[k] = 1; pa[k - 1] = w; k++; w = pa[k - 1]->rtrb_link[0]; } if ((w->rtrb_link[0] == NULL || w->rtrb_link[0]->rtrb_color == RTRB_BLACK) && (w->rtrb_rtag == RTRB_THREAD || w->rtrb_link[1]->rtrb_color == RTRB_BLACK)) { w->rtrb_color = RTRB_RED; } else { if (w->rtrb_link[0] == NULL || w->rtrb_link[0]->rtrb_color == RTRB_BLACK) { struct rtrb_node *y = w->rtrb_link[1]; y->rtrb_color = RTRB_BLACK; w->rtrb_color = RTRB_RED; w->rtrb_link[1] = y->rtrb_link[0]; y->rtrb_link[0] = w; w = pa[k - 1]->rtrb_link[0] = y; if (w->rtrb_link[0]->rtrb_link[1] == NULL) { w->rtrb_link[0]->rtrb_rtag = RTRB_THREAD; w->rtrb_link[0]->rtrb_link[1] = w; } } w->rtrb_color = pa[k - 1]->rtrb_color; pa[k - 1]->rtrb_color = RTRB_BLACK; w->rtrb_link[0]->rtrb_color = RTRB_BLACK; pa[k - 1]->rtrb_link[0] = w->rtrb_link[1]; w->rtrb_link[1] = pa[k - 1]; pa[k - 2]->rtrb_link[da[k - 2]] = w; if (w->rtrb_rtag == RTRB_THREAD) { w->rtrb_rtag = RTRB_CHILD; pa[k - 1]->rtrb_link[0] = NULL; } break; } } } if (tree->rtrb_root != NULL) tree->rtrb_root->rtrb_color = RTRB_BLACK; } tree->rtrb_alloc->libavl_free (tree->rtrb_alloc, p); return (void *) item; } /* Initializes |trav| for use with |tree| and selects the null node. */ void rtrb_t_init (struct rtrb_traverser *trav, struct rtrb_table *tree) { trav->rtrb_table = tree; trav->rtrb_node = NULL; } /* Initializes |trav| for |tree|. Returns data item in |tree| with the least value, or |NULL| if |tree| is empty. */ void * rtrb_t_first (struct rtrb_traverser *trav, struct rtrb_table *tree) { assert (tree != NULL && trav != NULL); trav->rtrb_table = tree; trav->rtrb_node = tree->rtrb_root; if (trav->rtrb_node != NULL) { while (trav->rtrb_node->rtrb_link[0] != NULL) trav->rtrb_node = trav->rtrb_node->rtrb_link[0]; return trav->rtrb_node->rtrb_data; } else return NULL; } /* Initializes |trav| for |tree|. Returns data item in |tree| with the greatest value, or |NULL| if |tree| is empty. */ void * rtrb_t_last (struct rtrb_traverser *trav, struct rtrb_table *tree) { assert (tree != NULL && trav != NULL); trav->rtrb_table = tree; trav->rtrb_node = tree->rtrb_root; if (trav->rtrb_node != NULL) { while (trav->rtrb_node->rtrb_rtag == RTRB_CHILD) trav->rtrb_node = trav->rtrb_node->rtrb_link[1]; return trav->rtrb_node->rtrb_data; } else return NULL; } /* Searches for |item| in |tree|. If found, initializes |trav| to the item found and returns the item as well. If there is no matching item, initializes |trav| to the null item and returns |NULL|. */ void * rtrb_t_find (struct rtrb_traverser *trav, struct rtrb_table *tree, void *item) { struct rtrb_node *p; assert (trav != NULL && tree != NULL && item != NULL); trav->rtrb_table = tree; trav->rtrb_node = NULL; p = tree->rtrb_root; if (p == NULL) return NULL; for (;;) { int cmp = tree->rtrb_compare (item, p->rtrb_data, tree->rtrb_param); if (cmp == 0) { trav->rtrb_node = p; return p->rtrb_data; } if (cmp < 0) { p = p->rtrb_link[0]; if (p == NULL) return NULL; } else { if (p->rtrb_rtag == RTRB_THREAD) return NULL; p = p->rtrb_link[1]; } } } /* Attempts to insert |item| into |tree|. If |item| is inserted successfully, it is returned and |trav| is initialized to its location. If a duplicate is found, it is returned and |trav| is initialized to its location. No replacement of the item occurs. If a memory allocation failure occurs, |NULL| is returned and |trav| is initialized to the null item. */ void * rtrb_t_insert (struct rtrb_traverser *trav, struct rtrb_table *tree, void *item) { void **p; assert (trav != NULL && tree != NULL && item != NULL); p = rtrb_probe (tree, item); if (p != NULL) { trav->rtrb_table = tree; trav->rtrb_node = ((struct rtrb_node *) ((char *) p - offsetof (struct rtrb_node, rtrb_data))); return *p; } else { rtrb_t_init (trav, tree); return NULL; } } /* Initializes |trav| to have the same current node as |src|. */ void * rtrb_t_copy (struct rtrb_traverser *trav, const struct rtrb_traverser *src) { assert (trav != NULL && src != NULL); trav->rtrb_table = src->rtrb_table; trav->rtrb_node = src->rtrb_node; return trav->rtrb_node != NULL ? trav->rtrb_node->rtrb_data : NULL; } /* Returns the next data item in inorder within the tree being traversed with |trav|, or if there are no more data items returns |NULL|. */ void * rtrb_t_next (struct rtrb_traverser *trav) { assert (trav != NULL); if (trav->rtrb_node == NULL) return rtrb_t_first (trav, trav->rtrb_table); else if (trav->rtrb_node->rtrb_rtag == RTRB_THREAD) { trav->rtrb_node = trav->rtrb_node->rtrb_link[1]; return trav->rtrb_node != NULL ? trav->rtrb_node->rtrb_data : NULL; } else { trav->rtrb_node = trav->rtrb_node->rtrb_link[1]; while (trav->rtrb_node->rtrb_link[0] != NULL) trav->rtrb_node = trav->rtrb_node->rtrb_link[0]; return trav->rtrb_node->rtrb_data; } } /* Returns the previous data item in inorder within the tree being traversed with |trav|, or if there are no more data items returns |NULL|. */ void * rtrb_t_prev (struct rtrb_traverser *trav) { assert (trav != NULL); if (trav->rtrb_node == NULL) return rtrb_t_last (trav, trav->rtrb_table); else if (trav->rtrb_node->rtrb_link[0] == NULL) { rtrb_comparison_func *cmp = trav->rtrb_table->rtrb_compare; void *param = trav->rtrb_table->rtrb_param; struct rtrb_node *node = trav->rtrb_node; struct rtrb_node *i; trav->rtrb_node = NULL; for (i = trav->rtrb_table->rtrb_root; i != node; ) { int dir = cmp (node->rtrb_data, i->rtrb_data, param) > 0; if (dir == 1) trav->rtrb_node = i; i = i->rtrb_link[dir]; } return trav->rtrb_node != NULL ? trav->rtrb_node->rtrb_data : NULL; } else { trav->rtrb_node = trav->rtrb_node->rtrb_link[0]; while (trav->rtrb_node->rtrb_rtag == RTRB_CHILD) trav->rtrb_node = trav->rtrb_node->rtrb_link[1]; return trav->rtrb_node->rtrb_data; } } /* Returns |trav|'s current item. */ void * rtrb_t_cur (struct rtrb_traverser *trav) { assert (trav != NULL); return trav->rtrb_node != NULL ? trav->rtrb_node->rtrb_data : NULL; } /* Replaces the current item in |trav| by |new| and returns the item replaced. |trav| must not have the null item selected. The new item must not upset the ordering of the tree. */ void * rtrb_t_replace (struct rtrb_traverser *trav, void *new) { void *old; assert (trav != NULL && trav->rtrb_node != NULL && new != NULL); old = trav->rtrb_node->rtrb_data; trav->rtrb_node->rtrb_data = new; return old; } /* Creates a new node as a child of |dst| on side |dir|. Copies data from |src| into the new node, applying |copy()|, if non-null. Returns nonzero only if fully successful. Regardless of success, integrity of the tree structure is assured, though failure may leave a null pointer in a |rtrb_data| member. */ static int copy_node (struct rtrb_table *tree, struct rtrb_node *dst, int dir, const struct rtrb_node *src, rtrb_copy_func *copy) { struct rtrb_node *new = tree->rtrb_alloc->libavl_malloc (tree->rtrb_alloc, sizeof *new); if (new == NULL) return 0; new->rtrb_link[0] = NULL; new->rtrb_rtag = RTRB_THREAD; if (dir == 0) new->rtrb_link[1] = dst; else { new->rtrb_link[1] = dst->rtrb_link[1]; dst->rtrb_rtag = RTRB_CHILD; } dst->rtrb_link[dir] = new; new->rtrb_color = src->rtrb_color; if (copy == NULL) new->rtrb_data = src->rtrb_data; else { new->rtrb_data = copy (src->rtrb_data, tree->rtrb_param); if (new->rtrb_data == NULL) return 0; } return 1; } /* Destroys |new| with |rtrb_destroy (new, destroy)|, first initializing right links in |new| that have not yet been initialized at time of call. */ static void copy_error_recovery (struct rtrb_table *new, rtrb_item_func *destroy) { struct rtrb_node *p = new->rtrb_root; if (p != NULL) { while (p->rtrb_rtag == RTRB_CHILD) p = p->rtrb_link[1]; p->rtrb_link[1] = NULL; } rtrb_destroy (new, destroy); } /* Copies |org| to a newly created tree, which is returned. If |copy != NULL|, each data item in |org| is first passed to |copy|, and the return values are inserted into the tree, with |NULL| return values are taken as indications of failure. On failure, destroys the partially created new tree, applying |destroy|, if non-null, to each item in the new tree so far, and returns |NULL|. If |allocator != NULL|, it is used for allocation in the new tree. Otherwise, the same allocator used for |org| is used. */ struct rtrb_table * rtrb_copy (const struct rtrb_table *org, rtrb_copy_func *copy, rtrb_item_func *destroy, struct libavl_allocator *allocator) { struct rtrb_table *new; const struct rtrb_node *p; struct rtrb_node *q; assert (org != NULL); new = rtrb_create (org->rtrb_compare, org->rtrb_param, allocator != NULL ? allocator : org->rtrb_alloc); if (new == NULL) return NULL; new->rtrb_count = org->rtrb_count; if (new->rtrb_count == 0) return new; p = (struct rtrb_node *) &org->rtrb_root; q = (struct rtrb_node *) &new->rtrb_root; for (;;) { if (p->rtrb_link[0] != NULL) { if (!copy_node (new, q, 0, p->rtrb_link[0], copy)) { copy_error_recovery (new, destroy); return NULL; } p = p->rtrb_link[0]; q = q->rtrb_link[0]; } else { while (p->rtrb_rtag == RTRB_THREAD) { p = p->rtrb_link[1]; if (p == NULL) { q->rtrb_link[1] = NULL; return new; } q = q->rtrb_link[1]; } p = p->rtrb_link[1]; q = q->rtrb_link[1]; } if (p->rtrb_rtag == RTRB_CHILD) if (!copy_node (new, q, 1, p->rtrb_link[1], copy)) { copy_error_recovery (new, destroy); return NULL; } } } /* Frees storage allocated for |tree|. If |destroy != NULL|, applies it to each data item in inorder. */ void rtrb_destroy (struct rtrb_table *tree, rtrb_item_func *destroy) { struct rtrb_node *p; /* Current node. */ struct rtrb_node *n; /* Next node. */ p = tree->rtrb_root; if (p != NULL) while (p->rtrb_link[0] != NULL) p = p->rtrb_link[0]; while (p != NULL) { n = p->rtrb_link[1]; if (p->rtrb_rtag == RTRB_CHILD) while (n->rtrb_link[0] != NULL) n = n->rtrb_link[0]; if (destroy != NULL && p->rtrb_data != NULL) destroy (p->rtrb_data, tree->rtrb_param); tree->rtrb_alloc->libavl_free (tree->rtrb_alloc, p); p = n; } tree->rtrb_alloc->libavl_free (tree->rtrb_alloc, tree); } /* Allocates |size| bytes of space using |malloc()|. Returns a null pointer if allocation fails. */ void * rtrb_malloc (struct libavl_allocator *allocator, size_t size) { assert (allocator != NULL && size > 0); return malloc (size); } /* Frees |block|. */ void rtrb_free (struct libavl_allocator *allocator, void *block) { assert (allocator != NULL && block != NULL); free (block); } /* Default memory allocator that uses |malloc()| and |free()|. */ struct libavl_allocator rtrb_allocator_default = { rtrb_malloc, rtrb_free }; #undef NDEBUG #include /* Asserts that |rtrb_insert()| succeeds at inserting |item| into |table|. */ void (rtrb_assert_insert) (struct rtrb_table *table, void *item) { void **p = rtrb_probe (table, item); assert (p != NULL && *p == item); } /* Asserts that |rtrb_delete()| really removes |item| from |table|, and returns the removed item. */ void * (rtrb_assert_delete) (struct rtrb_table *table, void *item) { void *p = rtrb_delete (table, item); assert (p != NULL); return p; }