suyu/src/common/tree.h
Lioncash b15e1a3501 common/tree: Convert defines over to templates
Reworks the tree header to operate off of templates as opposed to a
series of defines.

This allows all tree facilities to obey namespacing rules, and also
allows this code to be used within modules once compiler support is in
place.

This also gets rid to use a macro to define functions and structs for
necessary data types. With templates, these will be generated when
they're actually used, eliminating the need for the separate
declaration.
2021-01-12 16:46:36 -05:00

674 lines
17 KiB
C++

/* $NetBSD: tree.h,v 1.8 2004/03/28 19:38:30 provos Exp $ */
/* $OpenBSD: tree.h,v 1.7 2002/10/17 21:51:54 art Exp $ */
/* $FreeBSD$ */
/*-
* 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.
*/
#pragma once
/*
* This file defines data structures for red-black trees.
*
* A red-black tree is a binary search tree with the node color as an
* extra attribute. It fulfills a set of conditions:
* - every search path from the root to a leaf consists of the
* same number of black nodes,
* - each red node (except for the root) has a black parent,
* - each leaf node is black.
*
* Every operation on a red-black tree is bounded as O(lg n).
* The maximum height of a red-black tree is 2lg (n+1).
*/
namespace Common {
template <typename T>
class RBHead {
public:
[[nodiscard]] T* Root() {
return rbh_root;
}
[[nodiscard]] const T* Root() const {
return rbh_root;
}
void SetRoot(T* root) {
rbh_root = root;
}
[[nodiscard]] bool IsEmpty() const {
return Root() == nullptr;
}
private:
T* rbh_root = nullptr;
};
enum class EntryColor {
Black,
Red,
};
template <typename T>
class RBEntry {
public:
[[nodiscard]] T* Left() {
return rbe_left;
}
[[nodiscard]] const T* Left() const {
return rbe_left;
}
void SetLeft(T* left) {
rbe_left = left;
}
[[nodiscard]] T* Right() {
return rbe_right;
}
[[nodiscard]] const T* Right() const {
return rbe_right;
}
void SetRight(T* right) {
rbe_right = right;
}
[[nodiscard]] T* Parent() {
return rbe_parent;
}
[[nodiscard]] const T* Parent() const {
return rbe_parent;
}
void SetParent(T* parent) {
rbe_parent = parent;
}
[[nodiscard]] bool IsBlack() const {
return rbe_color == EntryColor::Black;
}
[[nodiscard]] bool IsRed() const {
return rbe_color == EntryColor::Red;
}
[[nodiscard]] EntryColor Color() const {
return rbe_color;
}
void SetColor(EntryColor color) {
rbe_color = color;
}
private:
T* rbe_left = nullptr;
T* rbe_right = nullptr;
T* rbe_parent = nullptr;
EntryColor rbe_color{};
};
template <typename Node>
[[nodiscard]] RBEntry<Node>& RB_ENTRY(Node* node) {
return node->GetEntry();
}
template <typename Node>
[[nodiscard]] const RBEntry<Node>& RB_ENTRY(const Node* node) {
return node->GetEntry();
}
template <typename Node>
[[nodiscard]] Node* RB_PARENT(Node* node) {
return RB_ENTRY(node).Parent();
}
template <typename Node>
[[nodiscard]] const Node* RB_PARENT(const Node* node) {
return RB_ENTRY(node).Parent();
}
template <typename Node>
void RB_SET_PARENT(Node* node, Node* parent) {
return RB_ENTRY(node).SetParent(parent);
}
template <typename Node>
[[nodiscard]] Node* RB_LEFT(Node* node) {
return RB_ENTRY(node).Left();
}
template <typename Node>
[[nodiscard]] const Node* RB_LEFT(const Node* node) {
return RB_ENTRY(node).Left();
}
template <typename Node>
void RB_SET_LEFT(Node* node, Node* left) {
return RB_ENTRY(node).SetLeft(left);
}
template <typename Node>
[[nodiscard]] Node* RB_RIGHT(Node* node) {
return RB_ENTRY(node).Right();
}
template <typename Node>
[[nodiscard]] const Node* RB_RIGHT(const Node* node) {
return RB_ENTRY(node).Right();
}
template <typename Node>
void RB_SET_RIGHT(Node* node, Node* right) {
return RB_ENTRY(node).SetRight(right);
}
template <typename Node>
[[nodiscard]] bool RB_IS_BLACK(const Node* node) {
return RB_ENTRY(node).IsBlack();
}
template <typename Node>
[[nodiscard]] bool RB_IS_RED(const Node* node) {
return RB_ENTRY(node).IsRed();
}
template <typename Node>
[[nodiscard]] EntryColor RB_COLOR(const Node* node) {
return RB_ENTRY(node).Color();
}
template <typename Node>
void RB_SET_COLOR(Node* node, EntryColor color) {
return RB_ENTRY(node).SetColor(color);
}
template <typename Node>
void RB_SET(Node* node, Node* parent) {
auto& entry = RB_ENTRY(node);
entry.SetParent(parent);
entry.SetLeft(nullptr);
entry.SetRight(nullptr);
entry.SetColor(EntryColor::Red);
}
template <typename Node>
void RB_SET_BLACKRED(Node* black, Node* red) {
RB_SET_COLOR(black, EntryColor::Black);
RB_SET_COLOR(red, EntryColor::Red);
}
template <typename Node>
void RB_ROTATE_LEFT(RBHead<Node>* head, Node* elm, Node*& tmp) {
tmp = RB_RIGHT(elm);
RB_SET_RIGHT(elm, RB_LEFT(tmp));
if (RB_RIGHT(elm) != nullptr) {
RB_SET_PARENT(RB_LEFT(tmp), elm);
}
RB_SET_PARENT(tmp, RB_PARENT(elm));
if (RB_PARENT(tmp) != nullptr) {
if (elm == RB_LEFT(RB_PARENT(elm))) {
RB_SET_LEFT(RB_PARENT(elm), tmp);
} else {
RB_SET_RIGHT(RB_PARENT(elm), tmp);
}
} else {
head->SetRoot(tmp);
}
RB_SET_LEFT(tmp, elm);
RB_SET_PARENT(elm, tmp);
}
template <typename Node>
void RB_ROTATE_RIGHT(RBHead<Node>* head, Node* elm, Node*& tmp) {
tmp = RB_LEFT(elm);
RB_SET_LEFT(elm, RB_RIGHT(tmp));
if (RB_LEFT(elm) != nullptr) {
RB_SET_PARENT(RB_RIGHT(tmp), elm);
}
RB_SET_PARENT(tmp, RB_PARENT(elm));
if (RB_PARENT(tmp) != nullptr) {
if (elm == RB_LEFT(RB_PARENT(elm))) {
RB_SET_LEFT(RB_PARENT(elm), tmp);
} else {
RB_SET_RIGHT(RB_PARENT(elm), tmp);
}
} else {
head->SetRoot(tmp);
}
RB_SET_RIGHT(tmp, elm);
RB_SET_PARENT(elm, tmp);
}
template <typename Node>
void RB_INSERT_COLOR(RBHead<Node>* head, Node* elm) {
Node* parent = nullptr;
Node* tmp = nullptr;
while ((parent = RB_PARENT(elm)) != nullptr && RB_IS_RED(parent)) {
Node* gparent = RB_PARENT(parent);
if (parent == RB_LEFT(gparent)) {
tmp = RB_RIGHT(gparent);
if (tmp && RB_IS_RED(tmp)) {
RB_SET_COLOR(tmp, EntryColor::Black);
RB_SET_BLACKRED(parent, gparent);
elm = gparent;
continue;
}
if (RB_RIGHT(parent) == elm) {
RB_ROTATE_LEFT(head, parent, tmp);
tmp = parent;
parent = elm;
elm = tmp;
}
RB_SET_BLACKRED(parent, gparent);
RB_ROTATE_RIGHT(head, gparent, tmp);
} else {
tmp = RB_LEFT(gparent);
if (tmp && RB_IS_RED(tmp)) {
RB_SET_COLOR(tmp, EntryColor::Black);
RB_SET_BLACKRED(parent, gparent);
elm = gparent;
continue;
}
if (RB_LEFT(parent) == elm) {
RB_ROTATE_RIGHT(head, parent, tmp);
tmp = parent;
parent = elm;
elm = tmp;
}
RB_SET_BLACKRED(parent, gparent);
RB_ROTATE_LEFT(head, gparent, tmp);
}
}
RB_SET_COLOR(head->Root(), EntryColor::Black);
}
template <typename Node>
void RB_REMOVE_COLOR(RBHead<Node>* head, Node* parent, Node* elm) {
Node* tmp;
while ((elm == nullptr || RB_IS_BLACK(elm)) && elm != head->Root()) {
if (RB_LEFT(parent) == elm) {
tmp = RB_RIGHT(parent);
if (RB_IS_RED(tmp)) {
RB_SET_BLACKRED(tmp, parent);
RB_ROTATE_LEFT(head, parent, tmp);
tmp = RB_RIGHT(parent);
}
if ((RB_LEFT(tmp) == nullptr || RB_IS_BLACK(RB_LEFT(tmp))) &&
(RB_RIGHT(tmp) == nullptr || RB_IS_BLACK(RB_RIGHT(tmp)))) {
RB_SET_COLOR(tmp, EntryColor::Red);
elm = parent;
parent = RB_PARENT(elm);
} else {
if (RB_RIGHT(tmp) == nullptr || RB_IS_BLACK(RB_RIGHT(tmp))) {
Node* oleft;
if ((oleft = RB_LEFT(tmp)) != nullptr) {
RB_SET_COLOR(oleft, EntryColor::Black);
}
RB_SET_COLOR(tmp, EntryColor::Red);
RB_ROTATE_RIGHT(head, tmp, oleft);
tmp = RB_RIGHT(parent);
}
RB_SET_COLOR(tmp, RB_COLOR(parent));
RB_SET_COLOR(parent, EntryColor::Black);
if (RB_RIGHT(tmp)) {
RB_SET_COLOR(RB_RIGHT(tmp), EntryColor::Black);
}
RB_ROTATE_LEFT(head, parent, tmp);
elm = head->Root();
break;
}
} else {
tmp = RB_LEFT(parent);
if (RB_IS_RED(tmp)) {
RB_SET_BLACKRED(tmp, parent);
RB_ROTATE_RIGHT(head, parent, tmp);
tmp = RB_LEFT(parent);
}
if ((RB_LEFT(tmp) == nullptr || RB_IS_BLACK(RB_LEFT(tmp))) &&
(RB_RIGHT(tmp) == nullptr || RB_IS_BLACK(RB_RIGHT(tmp)))) {
RB_SET_COLOR(tmp, EntryColor::Red);
elm = parent;
parent = RB_PARENT(elm);
} else {
if (RB_LEFT(tmp) == nullptr || RB_IS_BLACK(RB_LEFT(tmp))) {
Node* oright;
if ((oright = RB_RIGHT(tmp)) != nullptr) {
RB_SET_COLOR(oright, EntryColor::Black);
}
RB_SET_COLOR(tmp, EntryColor::Red);
RB_ROTATE_LEFT(head, tmp, oright);
tmp = RB_LEFT(parent);
}
RB_SET_COLOR(tmp, RB_COLOR(parent));
RB_SET_COLOR(parent, EntryColor::Black);
if (RB_LEFT(tmp)) {
RB_SET_COLOR(RB_LEFT(tmp), EntryColor::Black);
}
RB_ROTATE_RIGHT(head, parent, tmp);
elm = head->Root();
break;
}
}
}
if (elm) {
RB_SET_COLOR(elm, EntryColor::Black);
}
}
template <typename Node>
Node* RB_REMOVE(RBHead<Node>* head, Node* elm) {
Node* child = nullptr;
Node* parent = nullptr;
Node* old = elm;
EntryColor color{};
const auto finalize = [&] {
if (color == EntryColor::Black) {
RB_REMOVE_COLOR(head, parent, child);
}
return old;
};
if (RB_LEFT(elm) == nullptr) {
child = RB_RIGHT(elm);
} else if (RB_RIGHT(elm) == nullptr) {
child = RB_LEFT(elm);
} else {
Node* left;
elm = RB_RIGHT(elm);
while ((left = RB_LEFT(elm)) != nullptr) {
elm = left;
}
child = RB_RIGHT(elm);
parent = RB_PARENT(elm);
color = RB_COLOR(elm);
if (child) {
RB_SET_PARENT(child, parent);
}
if (parent) {
if (RB_LEFT(parent) == elm) {
RB_SET_LEFT(parent, child);
} else {
RB_SET_RIGHT(parent, child);
}
} else {
head->SetRoot(child);
}
if (RB_PARENT(elm) == old) {
parent = elm;
}
elm->SetEntry(old->GetEntry());
if (RB_PARENT(old)) {
if (RB_LEFT(RB_PARENT(old)) == old) {
RB_SET_LEFT(RB_PARENT(old), elm);
} else {
RB_SET_RIGHT(RB_PARENT(old), elm);
}
} else {
head->SetRoot(elm);
}
RB_SET_PARENT(RB_LEFT(old), elm);
if (RB_RIGHT(old)) {
RB_SET_PARENT(RB_RIGHT(old), elm);
}
if (parent) {
left = parent;
}
return finalize();
}
parent = RB_PARENT(elm);
color = RB_COLOR(elm);
if (child) {
RB_SET_PARENT(child, parent);
}
if (parent) {
if (RB_LEFT(parent) == elm) {
RB_SET_LEFT(parent, child);
} else {
RB_SET_RIGHT(parent, child);
}
} else {
head->SetRoot(child);
}
return finalize();
}
// Inserts a node into the RB tree
template <typename Node, typename CompareFunction>
Node* RB_INSERT(RBHead<Node>* head, Node* elm, CompareFunction cmp) {
Node* parent = nullptr;
Node* tmp = head->Root();
int comp = 0;
while (tmp) {
parent = tmp;
comp = cmp(elm, parent);
if (comp < 0) {
tmp = RB_LEFT(tmp);
} else if (comp > 0) {
tmp = RB_RIGHT(tmp);
} else {
return tmp;
}
}
RB_SET(elm, parent);
if (parent != nullptr) {
if (comp < 0) {
RB_SET_LEFT(parent, elm);
} else {
RB_SET_RIGHT(parent, elm);
}
} else {
head->SetRoot(elm);
}
RB_INSERT_COLOR(head, elm);
return nullptr;
}
// Finds the node with the same key as elm
template <typename Node, typename CompareFunction>
Node* RB_FIND(RBHead<Node>* head, Node* elm, CompareFunction cmp) {
Node* tmp = head->Root();
while (tmp) {
const int comp = cmp(elm, tmp);
if (comp < 0) {
tmp = RB_LEFT(tmp);
} else if (comp > 0) {
tmp = RB_RIGHT(tmp);
} else {
return tmp;
}
}
return nullptr;
}
// Finds the first node greater than or equal to the search key
template <typename Node, typename CompareFunction>
Node* RB_NFIND(RBHead<Node>* head, Node* elm, CompareFunction cmp) {
Node* tmp = head->Root();
Node* res = nullptr;
while (tmp) {
const int comp = cmp(elm, tmp);
if (comp < 0) {
res = tmp;
tmp = RB_LEFT(tmp);
} else if (comp > 0) {
tmp = RB_RIGHT(tmp);
} else {
return tmp;
}
}
return res;
}
// Finds the node with the same key as lelm
template <typename Node, typename CompareFunction>
Node* RB_FIND_LIGHT(RBHead<Node>* head, const void* lelm, CompareFunction lcmp) {
Node* tmp = head->Root();
while (tmp) {
const int comp = lcmp(lelm, tmp);
if (comp < 0) {
tmp = RB_LEFT(tmp);
} else if (comp > 0) {
tmp = RB_RIGHT(tmp);
} else {
return tmp;
}
}
return nullptr;
}
// Finds the first node greater than or equal to the search key
template <typename Node, typename CompareFunction>
Node* RB_NFIND_LIGHT(RBHead<Node>* head, const void* lelm, CompareFunction lcmp) {
Node* tmp = head->Root();
Node* res = nullptr;
while (tmp) {
const int comp = lcmp(lelm, tmp);
if (comp < 0) {
res = tmp;
tmp = RB_LEFT(tmp);
} else if (comp > 0) {
tmp = RB_RIGHT(tmp);
} else {
return tmp;
}
}
return res;
}
template <typename Node>
Node* RB_NEXT(Node* elm) {
if (RB_RIGHT(elm)) {
elm = RB_RIGHT(elm);
while (RB_LEFT(elm)) {
elm = RB_LEFT(elm);
}
} else {
if (RB_PARENT(elm) && (elm == RB_LEFT(RB_PARENT(elm)))) {
elm = RB_PARENT(elm);
} else {
while (RB_PARENT(elm) && (elm == RB_RIGHT(RB_PARENT(elm)))) {
elm = RB_PARENT(elm);
}
elm = RB_PARENT(elm);
}
}
return elm;
}
template <typename Node>
Node* RB_PREV(Node* elm) {
if (RB_LEFT(elm)) {
elm = RB_LEFT(elm);
while (RB_RIGHT(elm)) {
elm = RB_RIGHT(elm);
}
} else {
if (RB_PARENT(elm) && (elm == RB_RIGHT(RB_PARENT(elm)))) {
elm = RB_PARENT(elm);
} else {
while (RB_PARENT(elm) && (elm == RB_LEFT(RB_PARENT(elm)))) {
elm = RB_PARENT(elm);
}
elm = RB_PARENT(elm);
}
}
return elm;
}
template <typename Node>
Node* RB_MINMAX(RBHead<Node>* head, bool is_min) {
Node* tmp = head->Root();
Node* parent = nullptr;
while (tmp) {
parent = tmp;
if (is_min) {
tmp = RB_LEFT(tmp);
} else {
tmp = RB_RIGHT(tmp);
}
}
return parent;
}
template <typename Node>
Node* RB_MIN(RBHead<Node>* head) {
return RB_MINMAX(head, true);
}
template <typename Node>
Node* RB_MAX(RBHead<Node>* head) {
return RB_MINMAX(head, false);
}
} // namespace Common