1 files changed, 108 insertions, 0 deletions
diff --git a/vere/ext/nasm/include/rbtree.h b/vere/ext/nasm/include/rbtree.h
new file mode 100644
index 0000000..39d45af
--- /dev/null
+++ b/vere/ext/nasm/include/rbtree.h
@@ -0,0 +1,108 @@
+/* ----------------------------------------------------------------------- *
+ *
+ *   Copyright 1996-2020 The NASM Authors - All Rights Reserved
+ *   See the file AUTHORS included with the NASM distribution for
+ *   the specific copyright holders.
+ *
+ *   Redistribution and use in source and binary forms, with or without
+ *   modification, are permitted provided that the following
+ *   conditions are met:
+ *
+ *   * Redistributions of source code must retain the above copyright
+ *     notice, this list of conditions and the following disclaimer.
+ *   * 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 COPYRIGHT HOLDERS AND
+ *     CONTRIBUTORS "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 COPYRIGHT OWNER OR
+ *     CONTRIBUTORS 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.
+ *
+ * ----------------------------------------------------------------------- */
+
+#ifndef NASM_RBTREE_H
+#define NASM_RBTREE_H
+
+#include "compiler.h"
+
+/*
+ * This structure should be embedded in a larger data structure;
+ * the final output from rb_search() can then be converted back
+ * to the larger data structure via container_of().
+ *
+ * An empty tree is simply represented by a NULL pointer.
+ */
+
+/* Note: the values of these flags is significant */
+enum rbtree_node_flags {
+    RBTREE_NODE_BLACK	= 1,  /* Node color is black */
+    RBTREE_NODE_PRED    = 2,  /* Left pointer is an uplink */
+    RBTREE_NODE_SUCC    = 4   /* Right pointer is an uplink */
+};
+
+struct rbtree {
+    uint64_t key;
+    struct rbtree_metadata {
+        struct rbtree *left, *right;
+        enum rbtree_node_flags flags;
+    } m;
+};
+
+/*
+ * Add a node to a tree. Returns the new root pointer.
+ * The key value in the structure needs to be preinitialized;
+ * the rest of the structure should be zero.
+ */
+struct rbtree *rb_insert(struct rbtree *, struct rbtree *);
+
+/*
+ * Find a node in the tree corresponding to the key immediately
+ * <= the passed-in key value.
+ */
+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!)
+ * tree walk-with-destruction in key order.
+ */
+struct rbtree *rb_prev(const struct rbtree *);
+struct rbtree *rb_next(const struct rbtree *);
+
+/*
+ * Return the very first or very last node in key order.
+ */
+struct rbtree *rb_first(const struct rbtree *);
+struct rbtree *rb_last(const struct rbtree *);
+
+/*
+ * Left and right nodes, if real. These operations are
+ * safe for tree destruction, but not for splitting a tree.
+ */
+static inline struct rbtree *rb_left(const struct rbtree *rb)
+{
+    return (rb->m.flags & RBTREE_NODE_PRED) ? NULL : rb->m.left;
+}
+static inline struct rbtree *rb_right(const struct rbtree *rb)
+{
+    return (rb->m.flags & RBTREE_NODE_SUCC) ? NULL : rb->m.right;
+}
+
+#endif /* NASM_RBTREE_H */