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authorDavid Gwynne <dlg@cvs.openbsd.org>2017-06-19 03:06:27 +0000
committerDavid Gwynne <dlg@cvs.openbsd.org>2017-06-19 03:06:27 +0000
commit76977c1ae6d750e52e81faa456796b4fbf437246 (patch)
tree547fcad306bd1e36555ee4c659689f4a8d599367 /lib/libc/gen/tree.c
parenta80e66f3f5f1c5858727988469e7e5414555f389 (diff)
port the RBT code to userland by making it part of libc.
src/lib/libc/gen/tree.c is a copy of src/sys/kern/subr_tree.c, but with annotations for symbol visibility. changes to one should be reflected in the other. the malloc debug code that uses RB code is ported to RBT. because libc provides the RBT code, procmap doesn't have to reach into the kernel and build subr_tree.c itself now. mild enthusiasm from many ok guenther@
Diffstat (limited to 'lib/libc/gen/tree.c')
-rw-r--r--lib/libc/gen/tree.c655
1 files changed, 655 insertions, 0 deletions
diff --git a/lib/libc/gen/tree.c b/lib/libc/gen/tree.c
new file mode 100644
index 00000000000..e647a795dd7
--- /dev/null
+++ b/lib/libc/gen/tree.c
@@ -0,0 +1,655 @@
+/* $OpenBSD: tree.c,v 1.1 2017/06/19 03:06:26 dlg Exp $ */
+
+/*
+ * Copyright 2002 Niels Provos <provos@citi.umich.edu>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+/*
+ * Copyright (c) 2016 David Gwynne <dlg@openbsd.org>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <sys/tree.h>
+
+static inline struct rb_entry *
+rb_n2e(const struct rb_type *t, void *node)
+{
+ unsigned long addr = (unsigned long)node;
+
+ return ((struct rb_entry *)(addr + t->t_offset));
+}
+
+static inline void *
+rb_e2n(const struct rb_type *t, struct rb_entry *rbe)
+{
+ unsigned long addr = (unsigned long)rbe;
+
+ return ((void *)(addr - t->t_offset));
+}
+
+#define RBE_LEFT(_rbe) (_rbe)->rbt_left
+#define RBE_RIGHT(_rbe) (_rbe)->rbt_right
+#define RBE_PARENT(_rbe) (_rbe)->rbt_parent
+#define RBE_COLOR(_rbe) (_rbe)->rbt_color
+
+#define RBH_ROOT(_rbt) (_rbt)->rbt_root
+
+static inline void
+rbe_set(struct rb_entry *rbe, struct rb_entry *parent)
+{
+ RBE_PARENT(rbe) = parent;
+ RBE_LEFT(rbe) = RBE_RIGHT(rbe) = NULL;
+ RBE_COLOR(rbe) = RB_RED;
+}
+
+static inline void
+rbe_set_blackred(struct rb_entry *black, struct rb_entry *red)
+{
+ RBE_COLOR(black) = RB_BLACK;
+ RBE_COLOR(red) = RB_RED;
+}
+
+static inline void
+rbe_augment(const struct rb_type *t, struct rb_entry *rbe)
+{
+ (*t->t_augment)(rb_e2n(t, rbe));
+}
+
+static inline void
+rbe_if_augment(const struct rb_type *t, struct rb_entry *rbe)
+{
+ if (t->t_augment != NULL)
+ rbe_augment(t, rbe);
+}
+
+static inline void
+rbe_rotate_left(const struct rb_type *t, struct rb_tree *rbt,
+ struct rb_entry *rbe)
+{
+ struct rb_entry *parent;
+ struct rb_entry *tmp;
+
+ tmp = RBE_RIGHT(rbe);
+ RBE_RIGHT(rbe) = RBE_LEFT(tmp);
+ if (RBE_RIGHT(rbe) != NULL)
+ RBE_PARENT(RBE_LEFT(tmp)) = rbe;
+
+ parent = RBE_PARENT(rbe);
+ RBE_PARENT(tmp) = parent;
+ if (parent != NULL) {
+ if (rbe == RBE_LEFT(parent))
+ RBE_LEFT(parent) = tmp;
+ else
+ RBE_RIGHT(parent) = tmp;
+ } else
+ RBH_ROOT(rbt) = tmp;
+
+ RBE_LEFT(tmp) = rbe;
+ RBE_PARENT(rbe) = tmp;
+
+ if (t->t_augment != NULL) {
+ rbe_augment(t, rbe);
+ rbe_augment(t, tmp);
+ parent = RBE_PARENT(tmp);
+ if (parent != NULL)
+ rbe_augment(t, parent);
+ }
+}
+
+static inline void
+rbe_rotate_right(const struct rb_type *t, struct rb_tree *rbt,
+ struct rb_entry *rbe)
+{
+ struct rb_entry *parent;
+ struct rb_entry *tmp;
+
+ tmp = RBE_LEFT(rbe);
+ RBE_LEFT(rbe) = RBE_RIGHT(tmp);
+ if (RBE_LEFT(rbe) != NULL)
+ RBE_PARENT(RBE_RIGHT(tmp)) = rbe;
+
+ parent = RBE_PARENT(rbe);
+ RBE_PARENT(tmp) = parent;
+ if (parent != NULL) {
+ if (rbe == RBE_LEFT(parent))
+ RBE_LEFT(parent) = tmp;
+ else
+ RBE_RIGHT(parent) = tmp;
+ } else
+ RBH_ROOT(rbt) = tmp;
+
+ RBE_RIGHT(tmp) = rbe;
+ RBE_PARENT(rbe) = tmp;
+
+ if (t->t_augment != NULL) {
+ rbe_augment(t, rbe);
+ rbe_augment(t, tmp);
+ parent = RBE_PARENT(tmp);
+ if (parent != NULL)
+ rbe_augment(t, parent);
+ }
+}
+
+static inline void
+rbe_insert_color(const struct rb_type *t, struct rb_tree *rbt,
+ struct rb_entry *rbe)
+{
+ struct rb_entry *parent, *gparent, *tmp;
+
+ while ((parent = RBE_PARENT(rbe)) != NULL &&
+ RBE_COLOR(parent) == RB_RED) {
+ gparent = RBE_PARENT(parent);
+
+ if (parent == RBE_LEFT(gparent)) {
+ tmp = RBE_RIGHT(gparent);
+ if (tmp != NULL && RBE_COLOR(tmp) == RB_RED) {
+ RBE_COLOR(tmp) = RB_BLACK;
+ rbe_set_blackred(parent, gparent);
+ rbe = gparent;
+ continue;
+ }
+
+ if (RBE_RIGHT(parent) == rbe) {
+ rbe_rotate_left(t, rbt, parent);
+ tmp = parent;
+ parent = rbe;
+ rbe = tmp;
+ }
+
+ rbe_set_blackred(parent, gparent);
+ rbe_rotate_right(t, rbt, gparent);
+ } else {
+ tmp = RBE_LEFT(gparent);
+ if (tmp != NULL && RBE_COLOR(tmp) == RB_RED) {
+ RBE_COLOR(tmp) = RB_BLACK;
+ rbe_set_blackred(parent, gparent);
+ rbe = gparent;
+ continue;
+ }
+
+ if (RBE_LEFT(parent) == rbe) {
+ rbe_rotate_right(t, rbt, parent);
+ tmp = parent;
+ parent = rbe;
+ rbe = tmp;
+ }
+
+ rbe_set_blackred(parent, gparent);
+ rbe_rotate_left(t, rbt, gparent);
+ }
+ }
+
+ RBE_COLOR(RBH_ROOT(rbt)) = RB_BLACK;
+}
+
+static inline void
+rbe_remove_color(const struct rb_type *t, struct rb_tree *rbt,
+ struct rb_entry *parent, struct rb_entry *rbe)
+{
+ struct rb_entry *tmp;
+
+ while ((rbe == NULL || RBE_COLOR(rbe) == RB_BLACK) &&
+ rbe != RBH_ROOT(rbt)) {
+ if (RBE_LEFT(parent) == rbe) {
+ tmp = RBE_RIGHT(parent);
+ if (RBE_COLOR(tmp) == RB_RED) {
+ rbe_set_blackred(tmp, parent);
+ rbe_rotate_left(t, rbt, parent);
+ tmp = RBE_RIGHT(parent);
+ }
+ if ((RBE_LEFT(tmp) == NULL ||
+ RBE_COLOR(RBE_LEFT(tmp)) == RB_BLACK) &&
+ (RBE_RIGHT(tmp) == NULL ||
+ RBE_COLOR(RBE_RIGHT(tmp)) == RB_BLACK)) {
+ RBE_COLOR(tmp) = RB_RED;
+ rbe = parent;
+ parent = RBE_PARENT(rbe);
+ } else {
+ if (RBE_RIGHT(tmp) == NULL ||
+ RBE_COLOR(RBE_RIGHT(tmp)) == RB_BLACK) {
+ struct rb_entry *oleft;
+
+ oleft = RBE_LEFT(tmp);
+ if (oleft != NULL)
+ RBE_COLOR(oleft) = RB_BLACK;
+
+ RBE_COLOR(tmp) = RB_RED;
+ rbe_rotate_right(t, rbt, tmp);
+ tmp = RBE_RIGHT(parent);
+ }
+
+ RBE_COLOR(tmp) = RBE_COLOR(parent);
+ RBE_COLOR(parent) = RB_BLACK;
+ if (RBE_RIGHT(tmp))
+ RBE_COLOR(RBE_RIGHT(tmp)) = RB_BLACK;
+
+ rbe_rotate_left(t, rbt, parent);
+ rbe = RBH_ROOT(rbt);
+ break;
+ }
+ } else {
+ tmp = RBE_LEFT(parent);
+ if (RBE_COLOR(tmp) == RB_RED) {
+ rbe_set_blackred(tmp, parent);
+ rbe_rotate_right(t, rbt, parent);
+ tmp = RBE_LEFT(parent);
+ }
+
+ if ((RBE_LEFT(tmp) == NULL ||
+ RBE_COLOR(RBE_LEFT(tmp)) == RB_BLACK) &&
+ (RBE_RIGHT(tmp) == NULL ||
+ RBE_COLOR(RBE_RIGHT(tmp)) == RB_BLACK)) {
+ RBE_COLOR(tmp) = RB_RED;
+ rbe = parent;
+ parent = RBE_PARENT(rbe);
+ } else {
+ if (RBE_LEFT(tmp) == NULL ||
+ RBE_COLOR(RBE_LEFT(tmp)) == RB_BLACK) {
+ struct rb_entry *oright;
+
+ oright = RBE_RIGHT(tmp);
+ if (oright != NULL)
+ RBE_COLOR(oright) = RB_BLACK;
+
+ RBE_COLOR(tmp) = RB_RED;
+ rbe_rotate_left(t, rbt, tmp);
+ tmp = RBE_LEFT(parent);
+ }
+
+ RBE_COLOR(tmp) = RBE_COLOR(parent);
+ RBE_COLOR(parent) = RB_BLACK;
+ if (RBE_LEFT(tmp) != NULL)
+ RBE_COLOR(RBE_LEFT(tmp)) = RB_BLACK;
+
+ rbe_rotate_right(t, rbt, parent);
+ rbe = RBH_ROOT(rbt);
+ break;
+ }
+ }
+ }
+
+ if (rbe != NULL)
+ RBE_COLOR(rbe) = RB_BLACK;
+}
+
+static inline struct rb_entry *
+rbe_remove(const struct rb_type *t, struct rb_tree *rbt, struct rb_entry *rbe)
+{
+ struct rb_entry *child, *parent, *old = rbe;
+ unsigned int color;
+
+ if (RBE_LEFT(rbe) == NULL)
+ child = RBE_RIGHT(rbe);
+ else if (RBE_RIGHT(rbe) == NULL)
+ child = RBE_LEFT(rbe);
+ else {
+ struct rb_entry *tmp;
+
+ rbe = RBE_RIGHT(rbe);
+ while ((tmp = RBE_LEFT(rbe)) != NULL)
+ rbe = tmp;
+
+ child = RBE_RIGHT(rbe);
+ parent = RBE_PARENT(rbe);
+ color = RBE_COLOR(rbe);
+ if (child != NULL)
+ RBE_PARENT(child) = parent;
+ if (parent != NULL) {
+ if (RBE_LEFT(parent) == rbe)
+ RBE_LEFT(parent) = child;
+ else
+ RBE_RIGHT(parent) = child;
+
+ rbe_if_augment(t, parent);
+ } else
+ RBH_ROOT(rbt) = child;
+ if (RBE_PARENT(rbe) == old)
+ parent = rbe;
+ *rbe = *old;
+
+ tmp = RBE_PARENT(old);
+ if (tmp != NULL) {
+ if (RBE_LEFT(tmp) == old)
+ RBE_LEFT(tmp) = rbe;
+ else
+ RBE_RIGHT(tmp) = rbe;
+
+ rbe_if_augment(t, parent);
+ } else
+ RBH_ROOT(rbt) = rbe;
+
+ RBE_PARENT(RBE_LEFT(old)) = rbe;
+ if (RBE_RIGHT(old))
+ RBE_PARENT(RBE_RIGHT(old)) = rbe;
+
+ if (t->t_augment != NULL && parent != NULL) {
+ tmp = parent;
+ do {
+ rbe_augment(t, tmp);
+ tmp = RBE_PARENT(tmp);
+ } while (tmp != NULL);
+ }
+
+ goto color;
+ }
+
+ parent = RBE_PARENT(rbe);
+ color = RBE_COLOR(rbe);
+
+ if (child != NULL)
+ RBE_PARENT(child) = parent;
+ if (parent != NULL) {
+ if (RBE_LEFT(parent) == rbe)
+ RBE_LEFT(parent) = child;
+ else
+ RBE_RIGHT(parent) = child;
+
+ rbe_if_augment(t, parent);
+ } else
+ RBH_ROOT(rbt) = child;
+color:
+ if (color == RB_BLACK)
+ rbe_remove_color(t, rbt, parent, child);
+
+ return (old);
+}
+
+void *
+_rb_remove(const struct rb_type *t, struct rb_tree *rbt, void *elm)
+{
+ struct rb_entry *rbe = rb_n2e(t, elm);
+ struct rb_entry *old;
+
+ old = rbe_remove(t, rbt, rbe);
+
+ return (old == NULL ? NULL : rb_e2n(t, old));
+}
+DEF_STRONG(_rb_remove);
+
+void *
+_rb_insert(const struct rb_type *t, struct rb_tree *rbt, void *elm)
+{
+ struct rb_entry *rbe = rb_n2e(t, elm);
+ struct rb_entry *tmp;
+ struct rb_entry *parent = NULL;
+ void *node;
+ int comp = 0;
+
+ tmp = RBH_ROOT(rbt);
+ while (tmp != NULL) {
+ parent = tmp;
+
+ node = rb_e2n(t, tmp);
+ comp = (*t->t_compare)(elm, node);
+ if (comp < 0)
+ tmp = RBE_LEFT(tmp);
+ else if (comp > 0)
+ tmp = RBE_RIGHT(tmp);
+ else
+ return (node);
+ }
+
+ rbe_set(rbe, parent);
+
+ if (parent != NULL) {
+ if (comp < 0)
+ RBE_LEFT(parent) = rbe;
+ else
+ RBE_RIGHT(parent) = rbe;
+
+ rbe_if_augment(t, parent);
+ } else
+ RBH_ROOT(rbt) = rbe;
+
+ rbe_insert_color(t, rbt, rbe);
+
+ return (NULL);
+}
+DEF_STRONG(_rb_insert);
+
+/* Finds the node with the same key as elm */
+void *
+_rb_find(const struct rb_type *t, struct rb_tree *rbt, const void *key)
+{
+ struct rb_entry *tmp = RBH_ROOT(rbt);
+ void *node;
+ int comp;
+
+ while (tmp != NULL) {
+ node = rb_e2n(t, tmp);
+ comp = (*t->t_compare)(key, node);
+ if (comp < 0)
+ tmp = RBE_LEFT(tmp);
+ else if (comp > 0)
+ tmp = RBE_RIGHT(tmp);
+ else
+ return (node);
+ }
+
+ return (NULL);
+}
+DEF_STRONG(_rb_find);
+
+/* Finds the first node greater than or equal to the search key */
+void *
+_rb_nfind(const struct rb_type *t, struct rb_tree *rbt, const void *key)
+{
+ struct rb_entry *tmp = RBH_ROOT(rbt);
+ void *node;
+ void *res = NULL;
+ int comp;
+
+ while (tmp != NULL) {
+ node = rb_e2n(t, tmp);
+ comp = (*t->t_compare)(key, node);
+ if (comp < 0) {
+ res = node;
+ tmp = RBE_LEFT(tmp);
+ } else if (comp > 0)
+ tmp = RBE_RIGHT(tmp);
+ else
+ return (node);
+ }
+
+ return (res);
+}
+DEF_STRONG(_rb_nfind);
+
+void *
+_rb_next(const struct rb_type *t, void *elm)
+{
+ struct rb_entry *rbe = rb_n2e(t, elm);
+
+ if (RBE_RIGHT(rbe) != NULL) {
+ rbe = RBE_RIGHT(rbe);
+ while (RBE_LEFT(rbe) != NULL)
+ rbe = RBE_LEFT(rbe);
+ } else {
+ if (RBE_PARENT(rbe) &&
+ (rbe == RBE_LEFT(RBE_PARENT(rbe))))
+ rbe = RBE_PARENT(rbe);
+ else {
+ while (RBE_PARENT(rbe) &&
+ (rbe == RBE_RIGHT(RBE_PARENT(rbe))))
+ rbe = RBE_PARENT(rbe);
+ rbe = RBE_PARENT(rbe);
+ }
+ }
+
+ return (rbe == NULL ? NULL : rb_e2n(t, rbe));
+}
+DEF_STRONG(_rb_next);
+
+void *
+_rb_prev(const struct rb_type *t, void *elm)
+{
+ struct rb_entry *rbe = rb_n2e(t, elm);
+
+ if (RBE_LEFT(rbe)) {
+ rbe = RBE_LEFT(rbe);
+ while (RBE_RIGHT(rbe))
+ rbe = RBE_RIGHT(rbe);
+ } else {
+ if (RBE_PARENT(rbe) &&
+ (rbe == RBE_RIGHT(RBE_PARENT(rbe))))
+ rbe = RBE_PARENT(rbe);
+ else {
+ while (RBE_PARENT(rbe) &&
+ (rbe == RBE_LEFT(RBE_PARENT(rbe))))
+ rbe = RBE_PARENT(rbe);
+ rbe = RBE_PARENT(rbe);
+ }
+ }
+
+ return (rbe == NULL ? NULL : rb_e2n(t, rbe));
+}
+DEF_STRONG(_rb_prev);
+
+void *
+_rb_root(const struct rb_type *t, struct rb_tree *rbt)
+{
+ struct rb_entry *rbe = RBH_ROOT(rbt);
+
+ return (rbe == NULL ? rbe : rb_e2n(t, rbe));
+}
+DEF_STRONG(_rb_root);
+
+void *
+_rb_min(const struct rb_type *t, struct rb_tree *rbt)
+{
+ struct rb_entry *rbe = RBH_ROOT(rbt);
+ struct rb_entry *parent = NULL;
+
+ while (rbe != NULL) {
+ parent = rbe;
+ rbe = RBE_LEFT(rbe);
+ }
+
+ return (parent == NULL ? NULL : rb_e2n(t, parent));
+}
+DEF_STRONG(_rb_min);
+
+void *
+_rb_max(const struct rb_type *t, struct rb_tree *rbt)
+{
+ struct rb_entry *rbe = RBH_ROOT(rbt);
+ struct rb_entry *parent = NULL;
+
+ while (rbe != NULL) {
+ parent = rbe;
+ rbe = RBE_RIGHT(rbe);
+ }
+
+ return (parent == NULL ? NULL : rb_e2n(t, parent));
+}
+DEF_STRONG(_rb_max);
+
+void *
+_rb_left(const struct rb_type *t, void *node)
+{
+ struct rb_entry *rbe = rb_n2e(t, node);
+ rbe = RBE_LEFT(rbe);
+ return (rbe == NULL ? NULL : rb_e2n(t, rbe));
+}
+DEF_STRONG(_rb_left);
+
+void *
+_rb_right(const struct rb_type *t, void *node)
+{
+ struct rb_entry *rbe = rb_n2e(t, node);
+ rbe = RBE_RIGHT(rbe);
+ return (rbe == NULL ? NULL : rb_e2n(t, rbe));
+}
+DEF_STRONG(_rb_right);
+
+void *
+_rb_parent(const struct rb_type *t, void *node)
+{
+ struct rb_entry *rbe = rb_n2e(t, node);
+ rbe = RBE_PARENT(rbe);
+ return (rbe == NULL ? NULL : rb_e2n(t, rbe));
+}
+DEF_STRONG(_rb_parent);
+
+void
+_rb_set_left(const struct rb_type *t, void *node, void *left)
+{
+ struct rb_entry *rbe = rb_n2e(t, node);
+ struct rb_entry *rbl = (left == NULL) ? NULL : rb_n2e(t, left);
+
+ RBE_LEFT(rbe) = rbl;
+}
+DEF_STRONG(_rb_set_left);
+
+void
+_rb_set_right(const struct rb_type *t, void *node, void *right)
+{
+ struct rb_entry *rbe = rb_n2e(t, node);
+ struct rb_entry *rbr = (right == NULL) ? NULL : rb_n2e(t, right);
+
+ RBE_RIGHT(rbe) = rbr;
+}
+DEF_STRONG(_rb_set_right);
+
+void
+_rb_set_parent(const struct rb_type *t, void *node, void *parent)
+{
+ struct rb_entry *rbe = rb_n2e(t, node);
+ struct rb_entry *rbp = (parent == NULL) ? NULL : rb_n2e(t, parent);
+
+ RBE_PARENT(rbe) = rbp;
+}
+DEF_STRONG(_rb_set_parent);
+
+void
+_rb_poison(const struct rb_type *t, void *node, unsigned long poison)
+{
+ struct rb_entry *rbe = rb_n2e(t, node);
+
+ RBE_PARENT(rbe) = RBE_LEFT(rbe) = RBE_RIGHT(rbe) =
+ (struct rb_entry *)poison;
+}
+DEF_STRONG(_rb_poison);
+
+int
+_rb_check(const struct rb_type *t, void *node, unsigned long poison)
+{
+ struct rb_entry *rbe = rb_n2e(t, node);
+
+ return ((unsigned long)RBE_PARENT(rbe) == poison &&
+ (unsigned long)RBE_LEFT(rbe) == poison &&
+ (unsigned long)RBE_RIGHT(rbe) == poison);
+}
+DEF_STRONG(_rb_check);