From 68e3802b238b964900acac9422a70e295482243f Mon Sep 17 00:00:00 2001 From: "H. Peter Anvin (Intel)" Date: Wed, 8 Jul 2020 09:48:43 -0700 Subject: [PATCH] rbtree: add rb_search_exact() Sometimes we want to search for an exact key only, and reject the case when tree->key < key. Add rb_search_exact() for this purpose, rather than forcing the caller to perform the comparison in open code. Signed-off-by: H. Peter Anvin (Intel) --- include/rbtree.h | 5 +++++ nasmlib/rbtree.c | 8 ++++++++ 2 files changed, 13 insertions(+) diff --git a/include/rbtree.h b/include/rbtree.h index 332f6f85..39d45aff 100644 --- a/include/rbtree.h +++ b/include/rbtree.h @@ -73,6 +73,11 @@ struct rbtree *rb_insert(struct rbtree *, struct rbtree *); struct rbtree *rb_search(const struct rbtree *, uint64_t); /* + * Find a node in the tree exactly matching the key value. + */ +struct rbtree *rb_search_exact(const struct rbtree *, uint64_t); + +/* * Return the immediately previous or next node in key order. * Returns NULL if this node is the end of the tree. * These operations are safe for complee (but not partial!) diff --git a/nasmlib/rbtree.c b/nasmlib/rbtree.c index 510f34b1..773338bb 100644 --- a/nasmlib/rbtree.c +++ b/nasmlib/rbtree.c @@ -87,6 +87,14 @@ struct rbtree *rb_search(const struct rbtree *tree, uint64_t key) return (struct rbtree *)best; } +struct rbtree *rb_search_exact(const struct rbtree *tree, uint64_t key) +{ + struct rbtree *rv; + + rv = rb_search(tree, key); + return (rv && rv->key == key) ? rv : NULL; +} + /* Reds two left in a row? */ static inline bool is_red_left_left(struct rbtree *h) { -- 2.11.4.GIT