common: Introduce useful tree structures.

src/common/CMakeLists.txt

@@ -123,6 +123,7 @@ add_library(common STATIC
     hash.h
     hex_util.cpp
     hex_util.h
+    intrusive_red_black_tree.h
     logging/backend.cpp
     logging/backend.h
     logging/filter.cpp
@@ -143,6 +144,7 @@ add_library(common STATIC
     page_table.h
     param_package.cpp
     param_package.h
+    parent_of_member.h
     quaternion.h
     ring_buffer.h
     scm_rev.cpp
@@ -167,6 +169,7 @@ add_library(common STATIC
     time_zone.h
     timer.cpp
     timer.h
+    tree.h
     uint128.cpp
     uint128.h
     uuid.cpp

src/common/intrusive_red_black_tree.h

@@ -0,0 +1,627 @@
+// Copyright 2021 yuzu Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include "common/parent_of_member.h"
+#include "common/tree.h"
+
+namespace Common {
+
+namespace impl {
+
+class IntrusiveRedBlackTreeImpl;
+
+}
+
+struct IntrusiveRedBlackTreeNode {
+
+private:
+    RB_ENTRY(IntrusiveRedBlackTreeNode) entry{};
+
+    friend class impl::IntrusiveRedBlackTreeImpl;
+
+    template <class, class, class>
+    friend class IntrusiveRedBlackTree;
+
+public:
+    constexpr IntrusiveRedBlackTreeNode() = default;
+};
+
+template <class T, class Traits, class Comparator>
+class IntrusiveRedBlackTree;
+
+namespace impl {
+
+class IntrusiveRedBlackTreeImpl {
+
+private:
+    template <class, class, class>
+    friend class ::Common::IntrusiveRedBlackTree;
+
+private:
+    RB_HEAD(IntrusiveRedBlackTreeRoot, IntrusiveRedBlackTreeNode);
+    using RootType = IntrusiveRedBlackTreeRoot;
+
+private:
+    IntrusiveRedBlackTreeRoot root;
+
+public:
+    template <bool Const>
+    class Iterator;
+
+    using value_type = IntrusiveRedBlackTreeNode;
+    using size_type = size_t;
+    using difference_type = ptrdiff_t;
+    using pointer = value_type*;
+    using const_pointer = const value_type*;
+    using reference = value_type&;
+    using const_reference = const value_type&;
+    using iterator = Iterator<false>;
+    using const_iterator = Iterator<true>;
+
+    template <bool Const>
+    class Iterator {
+    public:
+        using iterator_category = std::bidirectional_iterator_tag;
+        using value_type = typename IntrusiveRedBlackTreeImpl::value_type;
+        using difference_type = typename IntrusiveRedBlackTreeImpl::difference_type;
+        using pointer = std::conditional_t<Const, IntrusiveRedBlackTreeImpl::const_pointer,
+                                           IntrusiveRedBlackTreeImpl::pointer>;
+        using reference = std::conditional_t<Const, IntrusiveRedBlackTreeImpl::const_reference,
+                                             IntrusiveRedBlackTreeImpl::reference>;
+
+    private:
+        pointer node;
+
+    public:
+        explicit Iterator(pointer n) : node(n) {}
+
+        bool operator==(const Iterator& rhs) const {
+            return this->node == rhs.node;
+        }
+
+        bool operator!=(const Iterator& rhs) const {
+            return !(*this == rhs);
+        }
+
+        pointer operator->() const {
+            return this->node;
+        }
+
+        reference operator*() const {
+            return *this->node;
+        }
+
+        Iterator& operator++() {
+            this->node = GetNext(this->node);
+            return *this;
+        }
+
+        Iterator& operator--() {
+            this->node = GetPrev(this->node);
+            return *this;
+        }
+
+        Iterator operator++(int) {
+            const Iterator it{*this};
+            ++(*this);
+            return it;
+        }
+
+        Iterator operator--(int) {
+            const Iterator it{*this};
+            --(*this);
+            return it;
+        }
+
+        operator Iterator<true>() const {
+            return Iterator<true>(this->node);
+        }
+    };
+
+protected:
+    // Generate static implementations for non-comparison operations for IntrusiveRedBlackTreeRoot.
+    RB_GENERATE_WITHOUT_COMPARE_STATIC(IntrusiveRedBlackTreeRoot, IntrusiveRedBlackTreeNode, entry);
+
+private:
+    // Define accessors using RB_* functions.
+    constexpr void InitializeImpl() {
+        RB_INIT(&this->root);
+    }
+
+    bool EmptyImpl() const {
+        return RB_EMPTY(&this->root);
+    }
+
+    IntrusiveRedBlackTreeNode* GetMinImpl() const {
+        return RB_MIN(IntrusiveRedBlackTreeRoot,
+                      const_cast<IntrusiveRedBlackTreeRoot*>(&this->root));
+    }
+
+    IntrusiveRedBlackTreeNode* GetMaxImpl() const {
+        return RB_MAX(IntrusiveRedBlackTreeRoot,
+                      const_cast<IntrusiveRedBlackTreeRoot*>(&this->root));
+    }
+
+    IntrusiveRedBlackTreeNode* RemoveImpl(IntrusiveRedBlackTreeNode* node) {
+        return RB_REMOVE(IntrusiveRedBlackTreeRoot, &this->root, node);
+    }
+
+public:
+    static IntrusiveRedBlackTreeNode* GetNext(IntrusiveRedBlackTreeNode* node) {
+        return RB_NEXT(IntrusiveRedBlackTreeRoot, nullptr, node);
+    }
+
+    static IntrusiveRedBlackTreeNode* GetPrev(IntrusiveRedBlackTreeNode* node) {
+        return RB_PREV(IntrusiveRedBlackTreeRoot, nullptr, node);
+    }
+
+    static IntrusiveRedBlackTreeNode const* GetNext(const IntrusiveRedBlackTreeNode* node) {
+        return static_cast<const IntrusiveRedBlackTreeNode*>(
+            GetNext(const_cast<IntrusiveRedBlackTreeNode*>(node)));
+    }
+
+    static IntrusiveRedBlackTreeNode const* GetPrev(const IntrusiveRedBlackTreeNode* node) {
+        return static_cast<const IntrusiveRedBlackTreeNode*>(
+            GetPrev(const_cast<IntrusiveRedBlackTreeNode*>(node)));
+    }
+
+public:
+    constexpr IntrusiveRedBlackTreeImpl() : root() {
+        this->InitializeImpl();
+    }
+
+    // Iterator accessors.
+    iterator begin() {
+        return iterator(this->GetMinImpl());
+    }
+
+    const_iterator begin() const {
+        return const_iterator(this->GetMinImpl());
+    }
+
+    iterator end() {
+        return iterator(static_cast<IntrusiveRedBlackTreeNode*>(nullptr));
+    }
+
+    const_iterator end() const {
+        return const_iterator(static_cast<const IntrusiveRedBlackTreeNode*>(nullptr));
+    }
+
+    const_iterator cbegin() const {
+        return this->begin();
+    }
+
+    const_iterator cend() const {
+        return this->end();
+    }
+
+    iterator iterator_to(reference ref) {
+        return iterator(&ref);
+    }
+
+    const_iterator iterator_to(const_reference ref) const {
+        return const_iterator(&ref);
+    }
+
+    // Content management.
+    bool empty() const {
+        return this->EmptyImpl();
+    }
+
+    reference back() {
+        return *this->GetMaxImpl();
+    }
+
+    const_reference back() const {
+        return *this->GetMaxImpl();
+    }
+
+    reference front() {
+        return *this->GetMinImpl();
+    }
+
+    const_reference front() const {
+        return *this->GetMinImpl();
+    }
+
+    iterator erase(iterator it) {
+        auto cur = std::addressof(*it);
+        auto next = GetNext(cur);
+        this->RemoveImpl(cur);
+        return iterator(next);
+    }
+};
+
+} // namespace impl
+
+template <typename T>
+concept HasLightCompareType = requires {
+    { std::is_same<typename T::LightCompareType, void>::value }
+    ->std::convertible_to<bool>;
+};
+
+namespace impl {
+
+template <typename T, typename Default>
+consteval auto* GetLightCompareType() {
+    if constexpr (HasLightCompareType<T>) {
+        return static_cast<typename T::LightCompareType*>(nullptr);
+    } else {
+        return static_cast<Default*>(nullptr);
+    }
+}
+
+} // namespace impl
+
+template <typename T, typename Default>
+using LightCompareType = std::remove_pointer_t<decltype(impl::GetLightCompareType<T, Default>())>;
+
+template <class T, class Traits, class Comparator>
+class IntrusiveRedBlackTree {
+
+public:
+    using ImplType = impl::IntrusiveRedBlackTreeImpl;
+
+private:
+    ImplType impl{};
+
+public:
+    struct IntrusiveRedBlackTreeRootWithCompare : ImplType::IntrusiveRedBlackTreeRoot {};
+
+    template <bool Const>
+    class Iterator;
+
+    using value_type = T;
+    using size_type = size_t;
+    using difference_type = ptrdiff_t;
+    using pointer = T*;
+    using const_pointer = const T*;
+    using reference = T&;
+    using const_reference = const T&;
+    using iterator = Iterator<false>;
+    using const_iterator = Iterator<true>;
+
+    using light_value_type = LightCompareType<Comparator, value_type>;
+    using const_light_pointer = const light_value_type*;
+    using const_light_reference = const light_value_type&;
+
+    template <bool Const>
+    class Iterator {
+    public:
+        friend class IntrusiveRedBlackTree<T, Traits, Comparator>;
+
+        using ImplIterator =
+            std::conditional_t<Const, ImplType::const_iterator, ImplType::iterator>;
+
+        using iterator_category = std::bidirectional_iterator_tag;
+        using value_type = typename IntrusiveRedBlackTree::value_type;
+        using difference_type = typename IntrusiveRedBlackTree::difference_type;
+        using pointer = std::conditional_t<Const, IntrusiveRedBlackTree::const_pointer,
+                                           IntrusiveRedBlackTree::pointer>;
+        using reference = std::conditional_t<Const, IntrusiveRedBlackTree::const_reference,
+                                             IntrusiveRedBlackTree::reference>;
+
+    private:
+        ImplIterator iterator;
+
+    private:
+        explicit Iterator(ImplIterator it) : iterator(it) {}
+
+        explicit Iterator(typename std::conditional<Const, ImplType::const_iterator,
+                                                    ImplType::iterator>::type::pointer ptr)
+            : iterator(ptr) {}
+
+        ImplIterator GetImplIterator() const {
+            return this->iterator;
+        }
+
+    public:
+        bool operator==(const Iterator& rhs) const {
+            return this->iterator == rhs.iterator;
+        }
+
+        bool operator!=(const Iterator& rhs) const {
+            return !(*this == rhs);
+        }
+
+        pointer operator->() const {
+            return Traits::GetParent(std::addressof(*this->iterator));
+        }
+
+        reference operator*() const {
+            return *Traits::GetParent(std::addressof(*this->iterator));
+        }
+
+        Iterator& operator++() {
+            ++this->iterator;
+            return *this;
+        }
+
+        Iterator& operator--() {
+            --this->iterator;
+            return *this;
+        }
+
+        Iterator operator++(int) {
+            const Iterator it{*this};
+            ++this->iterator;
+            return it;
+        }
+
+        Iterator operator--(int) {
+            const Iterator it{*this};
+            --this->iterator;
+            return it;
+        }
+
+        operator Iterator<true>() const {
+            return Iterator<true>(this->iterator);
+        }
+    };
+
+private:
+    // Generate static implementations for comparison operations for IntrusiveRedBlackTreeRoot.
+    RB_GENERATE_WITH_COMPARE_STATIC(IntrusiveRedBlackTreeRootWithCompare, IntrusiveRedBlackTreeNode,
+                                    entry, CompareImpl, LightCompareImpl);
+
+private:
+    static int CompareImpl(const IntrusiveRedBlackTreeNode* lhs,
+                           const IntrusiveRedBlackTreeNode* rhs) {
+        return Comparator::Compare(*Traits::GetParent(lhs), *Traits::GetParent(rhs));
+    }
+
+    static int LightCompareImpl(const void* elm, const IntrusiveRedBlackTreeNode* rhs) {
+        return Comparator::Compare(*static_cast<const_light_pointer>(elm), *Traits::GetParent(rhs));
+    }
+
+    // Define accessors using RB_* functions.
+    IntrusiveRedBlackTreeNode* InsertImpl(IntrusiveRedBlackTreeNode* node) {
+        return RB_INSERT(IntrusiveRedBlackTreeRootWithCompare,
+                         static_cast<IntrusiveRedBlackTreeRootWithCompare*>(&this->impl.root),
+                         node);
+    }
+
+    IntrusiveRedBlackTreeNode* FindImpl(const IntrusiveRedBlackTreeNode* node) const {
+        return RB_FIND(
+            IntrusiveRedBlackTreeRootWithCompare,
+            const_cast<IntrusiveRedBlackTreeRootWithCompare*>(
+                static_cast<const IntrusiveRedBlackTreeRootWithCompare*>(&this->impl.root)),
+            const_cast<IntrusiveRedBlackTreeNode*>(node));
+    }
+
+    IntrusiveRedBlackTreeNode* NFindImpl(const IntrusiveRedBlackTreeNode* node) const {
+        return RB_NFIND(
+            IntrusiveRedBlackTreeRootWithCompare,
+            const_cast<IntrusiveRedBlackTreeRootWithCompare*>(
+                static_cast<const IntrusiveRedBlackTreeRootWithCompare*>(&this->impl.root)),
+            const_cast<IntrusiveRedBlackTreeNode*>(node));
+    }
+
+    IntrusiveRedBlackTreeNode* FindLightImpl(const_light_pointer lelm) const {
+        return RB_FIND_LIGHT(
+            IntrusiveRedBlackTreeRootWithCompare,
+            const_cast<IntrusiveRedBlackTreeRootWithCompare*>(
+                static_cast<const IntrusiveRedBlackTreeRootWithCompare*>(&this->impl.root)),
+            static_cast<const void*>(lelm));
+    }
+
+    IntrusiveRedBlackTreeNode* NFindLightImpl(const_light_pointer lelm) const {
+        return RB_NFIND_LIGHT(
+            IntrusiveRedBlackTreeRootWithCompare,
+            const_cast<IntrusiveRedBlackTreeRootWithCompare*>(
+                static_cast<const IntrusiveRedBlackTreeRootWithCompare*>(&this->impl.root)),
+            static_cast<const void*>(lelm));
+    }
+
+public:
+    constexpr IntrusiveRedBlackTree() = default;
+
+    // Iterator accessors.
+    iterator begin() {
+        return iterator(this->impl.begin());
+    }
+
+    const_iterator begin() const {
+        return const_iterator(this->impl.begin());
+    }
+
+    iterator end() {
+        return iterator(this->impl.end());
+    }
+
+    const_iterator end() const {
+        return const_iterator(this->impl.end());
+    }
+
+    const_iterator cbegin() const {
+        return this->begin();
+    }
+
+    const_iterator cend() const {
+        return this->end();
+    }
+
+    iterator iterator_to(reference ref) {
+        return iterator(this->impl.iterator_to(*Traits::GetNode(std::addressof(ref))));
+    }
+
+    const_iterator iterator_to(const_reference ref) const {
+        return const_iterator(this->impl.iterator_to(*Traits::GetNode(std::addressof(ref))));
+    }
+
+    // Content management.
+    bool empty() const {
+        return this->impl.empty();
+    }
+
+    reference back() {
+        return *Traits::GetParent(std::addressof(this->impl.back()));
+    }
+
+    const_reference back() const {
+        return *Traits::GetParent(std::addressof(this->impl.back()));
+    }
+
+    reference front() {
+        return *Traits::GetParent(std::addressof(this->impl.front()));
+    }
+
+    const_reference front() const {
+        return *Traits::GetParent(std::addressof(this->impl.front()));
+    }
+
+    iterator erase(iterator it) {
+        return iterator(this->impl.erase(it.GetImplIterator()));
+    }
+
+    iterator insert(reference ref) {
+        ImplType::pointer node = Traits::GetNode(std::addressof(ref));
+        this->InsertImpl(node);
+        return iterator(node);
+    }
+
+    iterator find(const_reference ref) const {
+        return iterator(this->FindImpl(Traits::GetNode(std::addressof(ref))));
+    }
+
+    iterator nfind(const_reference ref) const {
+        return iterator(this->NFindImpl(Traits::GetNode(std::addressof(ref))));
+    }
+
+    iterator find_light(const_light_reference ref) const {
+        return iterator(this->FindLightImpl(std::addressof(ref)));
+    }
+
+    iterator nfind_light(const_light_reference ref) const {
+        return iterator(this->NFindLightImpl(std::addressof(ref)));
+    }
+};
+
+template <auto T, class Derived = impl::GetParentType<T>>
+class IntrusiveRedBlackTreeMemberTraits;
+
+template <class Parent, IntrusiveRedBlackTreeNode Parent::*Member, class Derived>
+class IntrusiveRedBlackTreeMemberTraits<Member, Derived> {
+public:
+    template <class Comparator>
+    using TreeType = IntrusiveRedBlackTree<Derived, IntrusiveRedBlackTreeMemberTraits, Comparator>;
+    using TreeTypeImpl = impl::IntrusiveRedBlackTreeImpl;
+
+private:
+    template <class, class, class>
+    friend class IntrusiveRedBlackTree;
+
+    friend class impl::IntrusiveRedBlackTreeImpl;
+
+    static constexpr IntrusiveRedBlackTreeNode* GetNode(Derived* parent) {
+        return std::addressof(parent->*Member);
+    }
+
+    static constexpr IntrusiveRedBlackTreeNode const* GetNode(Derived const* parent) {
+        return std::addressof(parent->*Member);
+    }
+
+    static constexpr Derived* GetParent(IntrusiveRedBlackTreeNode* node) {
+        return GetParentPointer<Member, Derived>(node);
+    }
+
+    static constexpr Derived const* GetParent(const IntrusiveRedBlackTreeNode* node) {
+        return GetParentPointer<Member, Derived>(node);
+    }
+
+private:
+    static constexpr TYPED_STORAGE(Derived) DerivedStorage = {};
+    static_assert(GetParent(GetNode(GetPointer(DerivedStorage))) == GetPointer(DerivedStorage));
+};
+
+template <auto T, class Derived = impl::GetParentType<T>>
+class IntrusiveRedBlackTreeMemberTraitsDeferredAssert;
+
+template <class Parent, IntrusiveRedBlackTreeNode Parent::*Member, class Derived>
+class IntrusiveRedBlackTreeMemberTraitsDeferredAssert<Member, Derived> {
+public:
+    template <class Comparator>
+    using TreeType =
+        IntrusiveRedBlackTree<Derived, IntrusiveRedBlackTreeMemberTraitsDeferredAssert, Comparator>;
+    using TreeTypeImpl = impl::IntrusiveRedBlackTreeImpl;
+
+    static constexpr bool IsValid() {
+        TYPED_STORAGE(Derived) DerivedStorage = {};
+        return GetParent(GetNode(GetPointer(DerivedStorage))) == GetPointer(DerivedStorage);
+    }
+
+private:
+    template <class, class, class>
+    friend class IntrusiveRedBlackTree;
+
+    friend class impl::IntrusiveRedBlackTreeImpl;
+
+    static constexpr IntrusiveRedBlackTreeNode* GetNode(Derived* parent) {
+        return std::addressof(parent->*Member);
+    }
+
+    static constexpr IntrusiveRedBlackTreeNode const* GetNode(Derived const* parent) {
+        return std::addressof(parent->*Member);
+    }
+
+    static constexpr Derived* GetParent(IntrusiveRedBlackTreeNode* node) {
+        return GetParentPointer<Member, Derived>(node);
+    }
+
+    static constexpr Derived const* GetParent(const IntrusiveRedBlackTreeNode* node) {
+        return GetParentPointer<Member, Derived>(node);
+    }
+};
+
+template <class Derived>
+class IntrusiveRedBlackTreeBaseNode : public IntrusiveRedBlackTreeNode {
+public:
+    constexpr Derived* GetPrev() {
+        return static_cast<Derived*>(impl::IntrusiveRedBlackTreeImpl::GetPrev(this));
+    }
+    constexpr const Derived* GetPrev() const {
+        return static_cast<const Derived*>(impl::IntrusiveRedBlackTreeImpl::GetPrev(this));
+    }
+
+    constexpr Derived* GetNext() {
+        return static_cast<Derived*>(impl::IntrusiveRedBlackTreeImpl::GetNext(this));
+    }
+    constexpr const Derived* GetNext() const {
+        return static_cast<const Derived*>(impl::IntrusiveRedBlackTreeImpl::GetNext(this));
+    }
+};
+
+template <class Derived>
+class IntrusiveRedBlackTreeBaseTraits {
+public:
+    template <class Comparator>
+    using TreeType = IntrusiveRedBlackTree<Derived, IntrusiveRedBlackTreeBaseTraits, Comparator>;
+    using TreeTypeImpl = impl::IntrusiveRedBlackTreeImpl;
+
+private:
+    template <class, class, class>
+    friend class IntrusiveRedBlackTree;
+
+    friend class impl::IntrusiveRedBlackTreeImpl;
+
+    static constexpr IntrusiveRedBlackTreeNode* GetNode(Derived* parent) {
+        return static_cast<IntrusiveRedBlackTreeNode*>(parent);
+    }
+
+    static constexpr IntrusiveRedBlackTreeNode const* GetNode(Derived const* parent) {
+        return static_cast<const IntrusiveRedBlackTreeNode*>(parent);
+    }
+
+    static constexpr Derived* GetParent(IntrusiveRedBlackTreeNode* node) {
+        return static_cast<Derived*>(node);
+    }
+
+    static constexpr Derived const* GetParent(const IntrusiveRedBlackTreeNode* node) {
+        return static_cast<const Derived*>(node);
+    }
+};
+
+} // namespace Common

src/common/parent_of_member.h

@@ -0,0 +1,189 @@
+// Copyright 2021 yuzu Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include <type_traits>
+
+#include "common/assert.h"
+#include "common/common_types.h"
+
+namespace Common {
+
+template <typename T, size_t Size, size_t Align>
+struct TypedStorage {
+    std::aligned_storage_t<Size, Align> storage_;
+};
+
+#define TYPED_STORAGE(...) TypedStorage<__VA_ARGS__, sizeof(__VA_ARGS__), alignof(__VA_ARGS__)>
+
+template <typename T>
+static constexpr T* GetPointer(TYPED_STORAGE(T) & ts) {
+    return static_cast<T*>(static_cast<void*>(std::addressof(ts.storage_)));
+}
+
+template <typename T>
+static constexpr const T* GetPointer(const TYPED_STORAGE(T) & ts) {
+    return static_cast<const T*>(static_cast<const void*>(std::addressof(ts.storage_)));
+}
+
+namespace impl {
+
+template <size_t MaxDepth>
+struct OffsetOfUnionHolder {
+    template <typename ParentType, typename MemberType, size_t Offset>
+    union UnionImpl {
+        using PaddingMember = char;
+        static constexpr size_t GetOffset() {
+            return Offset;
+        }
+
+#pragma pack(push, 1)
+        struct {
+            PaddingMember padding[Offset];
+            MemberType members[(sizeof(ParentType) / sizeof(MemberType)) + 1];
+        } data;
+#pragma pack(pop)
+        UnionImpl<ParentType, MemberType, Offset + 1> next_union;
+    };
+
+    template <typename ParentType, typename MemberType>
+    union UnionImpl<ParentType, MemberType, 0> {
+        static constexpr size_t GetOffset() {
+            return 0;
+        }
+
+        struct {
+            MemberType members[(sizeof(ParentType) / sizeof(MemberType)) + 1];
+        } data;
+        UnionImpl<ParentType, MemberType, 1> next_union;
+    };
+
+    template <typename ParentType, typename MemberType>
+    union UnionImpl<ParentType, MemberType, MaxDepth> {};
+};
+
+template <typename ParentType, typename MemberType>
+struct OffsetOfCalculator {
+    using UnionHolder =
+        typename OffsetOfUnionHolder<sizeof(MemberType)>::template UnionImpl<ParentType, MemberType,
+                                                                             0>;
+    union Union {
+        char c{};
+        UnionHolder first_union;
+        TYPED_STORAGE(ParentType) parent;
+
+        constexpr Union() : c() {}
+    };
+    static constexpr Union U = {};
+
+    static constexpr const MemberType* GetNextAddress(const MemberType* start,
+                                                      const MemberType* target) {
+        while (start < target) {
+            start++;
+        }
+        return start;
+    }
+
+    static constexpr std::ptrdiff_t GetDifference(const MemberType* start,
+                                                  const MemberType* target) {
+        return (target - start) * sizeof(MemberType);
+    }
+
+    template <typename CurUnion>
+    static constexpr std::ptrdiff_t OffsetOfImpl(MemberType ParentType::*member,
+                                                 CurUnion& cur_union) {
+        constexpr size_t Offset = CurUnion::GetOffset();
+        const auto target = std::addressof(GetPointer(U.parent)->*member);
+        const auto start = std::addressof(cur_union.data.members[0]);
+        const auto next = GetNextAddress(start, target);
+
+        if (next != target) {
+            if constexpr (Offset < sizeof(MemberType) - 1) {
+                return OffsetOfImpl(member, cur_union.next_union);
+            } else {
+                UNREACHABLE();
+            }
+        }
+
+        return (next - start) * sizeof(MemberType) + Offset;
+    }
+
+    static constexpr std::ptrdiff_t OffsetOf(MemberType ParentType::*member) {
+        return OffsetOfImpl(member, U.first_union);
+    }
+};
+
+template <typename T>
+struct GetMemberPointerTraits;
+
+template <typename P, typename M>
+struct GetMemberPointerTraits<M P::*> {
+    using Parent = P;
+    using Member = M;
+};
+
+template <auto MemberPtr>
+using GetParentType = typename GetMemberPointerTraits<decltype(MemberPtr)>::Parent;
+
+template <auto MemberPtr>
+using GetMemberType = typename GetMemberPointerTraits<decltype(MemberPtr)>::Member;
+
+template <auto MemberPtr, typename RealParentType = GetParentType<MemberPtr>>
+static inline std::ptrdiff_t OffsetOf = [] {
+    using DeducedParentType = GetParentType<MemberPtr>;
+    using MemberType = GetMemberType<MemberPtr>;
+    static_assert(std::is_base_of<DeducedParentType, RealParentType>::value ||
+                  std::is_same<RealParentType, DeducedParentType>::value);
+
+    return OffsetOfCalculator<RealParentType, MemberType>::OffsetOf(MemberPtr);
+}();
+
+} // namespace impl
+
+template <auto MemberPtr, typename RealParentType = impl::GetParentType<MemberPtr>>
+constexpr RealParentType& GetParentReference(impl::GetMemberType<MemberPtr>* member) {
+    std::ptrdiff_t Offset = impl::OffsetOf<MemberPtr, RealParentType>;
+    return *static_cast<RealParentType*>(
+        static_cast<void*>(static_cast<uint8_t*>(static_cast<void*>(member)) - Offset));
+}
+
+template <auto MemberPtr, typename RealParentType = impl::GetParentType<MemberPtr>>
+constexpr RealParentType const& GetParentReference(impl::GetMemberType<MemberPtr> const* member) {
+    std::ptrdiff_t Offset = impl::OffsetOf<MemberPtr, RealParentType>;
+    return *static_cast<const RealParentType*>(static_cast<const void*>(
+        static_cast<const uint8_t*>(static_cast<const void*>(member)) - Offset));
+}
+
+template <auto MemberPtr, typename RealParentType = impl::GetParentType<MemberPtr>>
+constexpr RealParentType* GetParentPointer(impl::GetMemberType<MemberPtr>* member) {
+    return std::addressof(GetParentReference<MemberPtr, RealParentType>(member));
+}
+
+template <auto MemberPtr, typename RealParentType = impl::GetParentType<MemberPtr>>
+constexpr RealParentType const* GetParentPointer(impl::GetMemberType<MemberPtr> const* member) {
+    return std::addressof(GetParentReference<MemberPtr, RealParentType>(member));
+}
+
+template <auto MemberPtr, typename RealParentType = impl::GetParentType<MemberPtr>>
+constexpr RealParentType& GetParentReference(impl::GetMemberType<MemberPtr>& member) {
+    return GetParentReference<MemberPtr, RealParentType>(std::addressof(member));
+}
+
+template <auto MemberPtr, typename RealParentType = impl::GetParentType<MemberPtr>>
+constexpr RealParentType const& GetParentReference(impl::GetMemberType<MemberPtr> const& member) {
+    return GetParentReference<MemberPtr, RealParentType>(std::addressof(member));
+}
+
+template <auto MemberPtr, typename RealParentType = impl::GetParentType<MemberPtr>>
+constexpr RealParentType* GetParentPointer(impl::GetMemberType<MemberPtr>& member) {
+    return std::addressof(GetParentReference<MemberPtr, RealParentType>(member));
+}
+
+template <auto MemberPtr, typename RealParentType = impl::GetParentType<MemberPtr>>
+constexpr RealParentType const* GetParentPointer(impl::GetMemberType<MemberPtr> const& member) {
+    return std::addressof(GetParentReference<MemberPtr, RealParentType>(member));
+}
+
+} // namespace Common

src/common/tree.h

@@ -0,0 +1,822 @@
+/* $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.
+ */
+
+#ifndef _SYS_TREE_H_
+#define _SYS_TREE_H_
+
+/* FreeBSD <sys/cdefs.h> has a lot of defines we don't really want. */
+/* tree.h only actually uses __inline and __unused, so we'll just define those. */
+
+/* #include <sys/cdefs.h> */
+
+#ifndef __inline
+#define __inline inline
+#endif
+
+/*
+ * This file defines data structures for different types of trees:
+ * splay trees and red-black trees.
+ *
+ * A splay tree is a self-organizing data structure.  Every operation
+ * on the tree causes a splay to happen.  The splay moves the requested
+ * node to the root of the tree and partly rebalances it.
+ *
+ * This has the benefit that request locality causes faster lookups as
+ * the requested nodes move to the top of the tree.  On the other hand,
+ * every lookup causes memory writes.
+ *
+ * The Balance Theorem bounds the total access time for m operations
+ * and n inserts on an initially empty tree as O((m + n)lg n).  The
+ * amortized cost for a sequence of m accesses to a splay tree is O(lg n);
+ *
+ * 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).
+ */
+
+#define SPLAY_HEAD(name, type)                                                                     \
+    struct name {                                                                                  \
+        struct type* sph_root; /* root of the tree */                                              \
+    }
+
+#define SPLAY_INITIALIZER(root)                                                                    \
+    { NULL }
+
+#define SPLAY_INIT(root)                                                                           \
+    do {                                                                                           \
+        (root)->sph_root = NULL;                                                                   \
+    } while (/*CONSTCOND*/ 0)
+
+#define SPLAY_ENTRY(type)                                                                          \
+    struct {                                                                                       \
+        struct type* spe_left;  /* left element */                                                 \
+        struct type* spe_right; /* right element */                                                \
+    }
+
+#define SPLAY_LEFT(elm, field) (elm)->field.spe_left
+#define SPLAY_RIGHT(elm, field) (elm)->field.spe_right
+#define SPLAY_ROOT(head) (head)->sph_root
+#define SPLAY_EMPTY(head) (SPLAY_ROOT(head) == NULL)
+
+/* SPLAY_ROTATE_{LEFT,RIGHT} expect that tmp hold SPLAY_{RIGHT,LEFT} */
+#define SPLAY_ROTATE_RIGHT(head, tmp, field)                                                       \
+    do {                                                                                           \
+        SPLAY_LEFT((head)->sph_root, field) = SPLAY_RIGHT(tmp, field);                             \
+        SPLAY_RIGHT(tmp, field) = (head)->sph_root;                                                \
+        (head)->sph_root = tmp;                                                                    \
+    } while (/*CONSTCOND*/ 0)
+
+#define SPLAY_ROTATE_LEFT(head, tmp, field)                                                        \
+    do {                                                                                           \
+        SPLAY_RIGHT((head)->sph_root, field) = SPLAY_LEFT(tmp, field);                             \
+        SPLAY_LEFT(tmp, field) = (head)->sph_root;                                                 \
+        (head)->sph_root = tmp;                                                                    \
+    } while (/*CONSTCOND*/ 0)
+
+#define SPLAY_LINKLEFT(head, tmp, field)                                                           \
+    do {                                                                                           \
+        SPLAY_LEFT(tmp, field) = (head)->sph_root;                                                 \
+        tmp = (head)->sph_root;                                                                    \
+        (head)->sph_root = SPLAY_LEFT((head)->sph_root, field);                                    \
+    } while (/*CONSTCOND*/ 0)
+
+#define SPLAY_LINKRIGHT(head, tmp, field)                                                          \
+    do {                                                                                           \
+        SPLAY_RIGHT(tmp, field) = (head)->sph_root;                                                \
+        tmp = (head)->sph_root;                                                                    \
+        (head)->sph_root = SPLAY_RIGHT((head)->sph_root, field);                                   \
+    } while (/*CONSTCOND*/ 0)
+
+#define SPLAY_ASSEMBLE(head, node, left, right, field)                                             \
+    do {                                                                                           \
+        SPLAY_RIGHT(left, field) = SPLAY_LEFT((head)->sph_root, field);                            \
+        SPLAY_LEFT(right, field) = SPLAY_RIGHT((head)->sph_root, field);                           \
+        SPLAY_LEFT((head)->sph_root, field) = SPLAY_RIGHT(node, field);                            \
+        SPLAY_RIGHT((head)->sph_root, field) = SPLAY_LEFT(node, field);                            \
+    } while (/*CONSTCOND*/ 0)
+
+/* Generates prototypes and inline functions */
+
+#define SPLAY_PROTOTYPE(name, type, field, cmp)                                                    \
+    void name##_SPLAY(struct name*, struct type*);                                                 \
+    void name##_SPLAY_MINMAX(struct name*, int);                                                   \
+    struct type* name##_SPLAY_INSERT(struct name*, struct type*);                                  \
+    struct type* name##_SPLAY_REMOVE(struct name*, struct type*);                                  \
+                                                                                                   \
+    /* Finds the node with the same key as elm */                                                  \
+    static __inline struct type* name##_SPLAY_FIND(struct name* head, struct type* elm) {          \
+        if (SPLAY_EMPTY(head))                                                                     \
+            return (NULL);                                                                         \
+        name##_SPLAY(head, elm);                                                                   \
+        if ((cmp)(elm, (head)->sph_root) == 0)                                                     \
+            return (head->sph_root);                                                               \
+        return (NULL);                                                                             \
+    }                                                                                              \
+                                                                                                   \
+    static __inline struct type* name##_SPLAY_NEXT(struct name* head, struct type* elm) {          \
+        name##_SPLAY(head, elm);                                                                   \
+        if (SPLAY_RIGHT(elm, field) != NULL) {                                                     \
+            elm = SPLAY_RIGHT(elm, field);                                                         \
+            while (SPLAY_LEFT(elm, field) != NULL) {                                               \
+                elm = SPLAY_LEFT(elm, field);                                                      \
+            }                                                                                      \
+        } else                                                                                     \
+            elm = NULL;                                                                            \
+        return (elm);                                                                              \
+    }                                                                                              \
+                                                                                                   \
+    static __inline struct type* name##_SPLAY_MIN_MAX(struct name* head, int val) {                \
+        name##_SPLAY_MINMAX(head, val);                                                            \
+        return (SPLAY_ROOT(head));                                                                 \
+    }
+
+/* Main splay operation.
+ * Moves node close to the key of elm to top
+ */
+#define SPLAY_GENERATE(name, type, field, cmp)                                                     \
+    struct type* name##_SPLAY_INSERT(struct name* head, struct type* elm) {                        \
+        if (SPLAY_EMPTY(head)) {                                                                   \
+            SPLAY_LEFT(elm, field) = SPLAY_RIGHT(elm, field) = NULL;                               \
+        } else {                                                                                   \
+            int __comp;                                                                            \
+            name##_SPLAY(head, elm);                                                               \
+            __comp = (cmp)(elm, (head)->sph_root);                                                 \
+            if (__comp < 0) {                                                                      \
+                SPLAY_LEFT(elm, field) = SPLAY_LEFT((head)->sph_root, field);                      \
+                SPLAY_RIGHT(elm, field) = (head)->sph_root;                                        \
+                SPLAY_LEFT((head)->sph_root, field) = NULL;                                        \
+            } else if (__comp > 0) {                                                               \
+                SPLAY_RIGHT(elm, field) = SPLAY_RIGHT((head)->sph_root, field);                    \
+                SPLAY_LEFT(elm, field) = (head)->sph_root;                                         \
+                SPLAY_RIGHT((head)->sph_root, field) = NULL;                                       \
+            } else                                                                                 \
+                return ((head)->sph_root);                                                         \
+        }                                                                                          \
+        (head)->sph_root = (elm);                                                                  \
+        return (NULL);                                                                             \
+    }                                                                                              \
+                                                                                                   \
+    struct type* name##_SPLAY_REMOVE(struct name* head, struct type* elm) {                        \
+        struct type* __tmp;                                                                        \
+        if (SPLAY_EMPTY(head))                                                                     \
+            return (NULL);                                                                         \
+        name##_SPLAY(head, elm);                                                                   \
+        if ((cmp)(elm, (head)->sph_root) == 0) {                                                   \
+            if (SPLAY_LEFT((head)->sph_root, field) == NULL) {                                     \
+                (head)->sph_root = SPLAY_RIGHT((head)->sph_root, field);                           \
+            } else {                                                                               \
+                __tmp = SPLAY_RIGHT((head)->sph_root, field);                                      \
+                (head)->sph_root = SPLAY_LEFT((head)->sph_root, field);                            \
+                name##_SPLAY(head, elm);                                                           \
+                SPLAY_RIGHT((head)->sph_root, field) = __tmp;                                      \
+            }                                                                                      \
+            return (elm);                                                                          \
+        }                                                                                          \
+        return (NULL);                                                                             \
+    }                                                                                              \
+                                                                                                   \
+    void name##_SPLAY(struct name* head, struct type* elm) {                                       \
+        struct type __node, *__left, *__right, *__tmp;                                             \
+        int __comp;                                                                                \
+                                                                                                   \
+        SPLAY_LEFT(&__node, field) = SPLAY_RIGHT(&__node, field) = NULL;                           \
+        __left = __right = &__node;                                                                \
+                                                                                                   \
+        while ((__comp = (cmp)(elm, (head)->sph_root)) != 0) {                                     \
+            if (__comp < 0) {                                                                      \
+                __tmp = SPLAY_LEFT((head)->sph_root, field);                                       \
+                if (__tmp == NULL)                                                                 \
+                    break;                                                                         \
+                if ((cmp)(elm, __tmp) < 0) {                                                       \
+                    SPLAY_ROTATE_RIGHT(head, __tmp, field);                                        \
+                    if (SPLAY_LEFT((head)->sph_root, field) == NULL)                               \
+                        break;                                                                     \
+                }                                                                                  \
+                SPLAY_LINKLEFT(head, __right, field);                                              \
+            } else if (__comp > 0) {                                                               \
+                __tmp = SPLAY_RIGHT((head)->sph_root, field);                                      \
+                if (__tmp == NULL)                                                                 \
+                    break;                                                                         \
+                if ((cmp)(elm, __tmp) > 0) {                                                       \
+                    SPLAY_ROTATE_LEFT(head, __tmp, field);                                         \
+                    if (SPLAY_RIGHT((head)->sph_root, field) == NULL)                              \
+                        break;                                                                     \
+                }                                                                                  \
+                SPLAY_LINKRIGHT(head, __left, field);                                              \
+            }                                                                                      \
+        }                                                                                          \
+        SPLAY_ASSEMBLE(head, &__node, __left, __right, field);                                     \
+    }                                                                                              \
+                                                                                                   \
+    /* Splay with either the minimum or the maximum element                                        \
+     * Used to find minimum or maximum element in tree.                                            \
+     */                                                                                            \
+    void name##_SPLAY_MINMAX(struct name* head, int __comp) {                                      \
+        struct type __node, *__left, *__right, *__tmp;                                             \
+                                                                                                   \
+        SPLAY_LEFT(&__node, field) = SPLAY_RIGHT(&__node, field) = NULL;                           \
+        __left = __right = &__node;                                                                \
+                                                                                                   \
+        while (1) {                                                                                \
+            if (__comp < 0) {                                                                      \
+                __tmp = SPLAY_LEFT((head)->sph_root, field);                                       \
+                if (__tmp == NULL)                                                                 \
+                    break;                                                                         \
+                if (__comp < 0) {                                                                  \
+                    SPLAY_ROTATE_RIGHT(head, __tmp, field);                                        \
+                    if (SPLAY_LEFT((head)->sph_root, field) == NULL)                               \
+                        break;                                                                     \
+                }                                                                                  \
+                SPLAY_LINKLEFT(head, __right, field);                                              \
+            } else if (__comp > 0) {                                                               \
+                __tmp = SPLAY_RIGHT((head)->sph_root, field);                                      \
+                if (__tmp == NULL)                                                                 \
+                    break;                                                                         \
+                if (__comp > 0) {                                                                  \
+                    SPLAY_ROTATE_LEFT(head, __tmp, field);                                         \
+                    if (SPLAY_RIGHT((head)->sph_root, field) == NULL)                              \
+                        break;                                                                     \
+                }                                                                                  \
+                SPLAY_LINKRIGHT(head, __left, field);                                              \
+            }                                                                                      \
+        }                                                                                          \
+        SPLAY_ASSEMBLE(head, &__node, __left, __right, field);                                     \
+    }
+
+#define SPLAY_NEGINF -1
+#define SPLAY_INF 1
+
+#define SPLAY_INSERT(name, x, y) name##_SPLAY_INSERT(x, y)
+#define SPLAY_REMOVE(name, x, y) name##_SPLAY_REMOVE(x, y)
+#define SPLAY_FIND(name, x, y) name##_SPLAY_FIND(x, y)
+#define SPLAY_NEXT(name, x, y) name##_SPLAY_NEXT(x, y)
+#define SPLAY_MIN(name, x) (SPLAY_EMPTY(x) ? NULL : name##_SPLAY_MIN_MAX(x, SPLAY_NEGINF))
+#define SPLAY_MAX(name, x) (SPLAY_EMPTY(x) ? NULL : name##_SPLAY_MIN_MAX(x, SPLAY_INF))
+
+#define SPLAY_FOREACH(x, name, head)                                                               \
+    for ((x) = SPLAY_MIN(name, head); (x) != NULL; (x) = SPLAY_NEXT(name, head, x))
+
+/* Macros that define a red-black tree */
+#define RB_HEAD(name, type)                                                                        \
+    struct name {                                                                                  \
+        struct type* rbh_root; /* root of the tree */                                              \
+    }
+
+#define RB_INITIALIZER(root)                                                                       \
+    { NULL }
+
+#define RB_INIT(root)                                                                              \
+    do {                                                                                           \
+        (root)->rbh_root = NULL;                                                                   \
+    } while (/*CONSTCOND*/ 0)
+
+#define RB_BLACK 0
+#define RB_RED 1
+#define RB_ENTRY(type)                                                                             \
+    struct {                                                                                       \
+        struct type* rbe_left;   /* left element */                                                \
+        struct type* rbe_right;  /* right element */                                               \
+        struct type* rbe_parent; /* parent element */                                              \
+        int rbe_color;           /* node color */                                                  \
+    }
+
+#define RB_LEFT(elm, field) (elm)->field.rbe_left
+#define RB_RIGHT(elm, field) (elm)->field.rbe_right
+#define RB_PARENT(elm, field) (elm)->field.rbe_parent
+#define RB_COLOR(elm, field) (elm)->field.rbe_color
+#define RB_ROOT(head) (head)->rbh_root
+#define RB_EMPTY(head) (RB_ROOT(head) == NULL)
+
+#define RB_SET(elm, parent, field)                                                                 \
+    do {                                                                                           \
+        RB_PARENT(elm, field) = parent;                                                            \
+        RB_LEFT(elm, field) = RB_RIGHT(elm, field) = NULL;                                         \
+        RB_COLOR(elm, field) = RB_RED;                                                             \
+    } while (/*CONSTCOND*/ 0)
+
+#define RB_SET_BLACKRED(black, red, field)                                                         \
+    do {                                                                                           \
+        RB_COLOR(black, field) = RB_BLACK;                                                         \
+        RB_COLOR(red, field) = RB_RED;                                                             \
+    } while (/*CONSTCOND*/ 0)
+
+#ifndef RB_AUGMENT
+#define RB_AUGMENT(x)                                                                              \
+    do {                                                                                           \
+    } while (0)
+#endif
+
+#define RB_ROTATE_LEFT(head, elm, tmp, field)                                                      \
+    do {                                                                                           \
+        (tmp) = RB_RIGHT(elm, field);                                                              \
+        if ((RB_RIGHT(elm, field) = RB_LEFT(tmp, field)) != NULL) {                                \
+            RB_PARENT(RB_LEFT(tmp, field), field) = (elm);                                         \
+        }                                                                                          \
+        RB_AUGMENT(elm);                                                                           \
+        if ((RB_PARENT(tmp, field) = RB_PARENT(elm, field)) != NULL) {                             \
+            if ((elm) == RB_LEFT(RB_PARENT(elm, field), field))                                    \
+                RB_LEFT(RB_PARENT(elm, field), field) = (tmp);                                     \
+            else                                                                                   \
+                RB_RIGHT(RB_PARENT(elm, field), field) = (tmp);                                    \
+        } else                                                                                     \
+            (head)->rbh_root = (tmp);                                                              \
+        RB_LEFT(tmp, field) = (elm);                                                               \
+        RB_PARENT(elm, field) = (tmp);                                                             \
+        RB_AUGMENT(tmp);                                                                           \
+        if ((RB_PARENT(tmp, field)))                                                               \
+            RB_AUGMENT(RB_PARENT(tmp, field));                                                     \
+    } while (/*CONSTCOND*/ 0)
+
+#define RB_ROTATE_RIGHT(head, elm, tmp, field)                                                     \
+    do {                                                                                           \
+        (tmp) = RB_LEFT(elm, field);                                                               \
+        if ((RB_LEFT(elm, field) = RB_RIGHT(tmp, field)) != NULL) {                                \
+            RB_PARENT(RB_RIGHT(tmp, field), field) = (elm);                                        \
+        }                                                                                          \
+        RB_AUGMENT(elm);                                                                           \
+        if ((RB_PARENT(tmp, field) = RB_PARENT(elm, field)) != NULL) {                             \
+            if ((elm) == RB_LEFT(RB_PARENT(elm, field), field))                                    \
+                RB_LEFT(RB_PARENT(elm, field), field) = (tmp);                                     \
+            else                                                                                   \
+                RB_RIGHT(RB_PARENT(elm, field), field) = (tmp);                                    \
+        } else                                                                                     \
+            (head)->rbh_root = (tmp);                                                              \
+        RB_RIGHT(tmp, field) = (elm);                                                              \
+        RB_PARENT(elm, field) = (tmp);                                                             \
+        RB_AUGMENT(tmp);                                                                           \
+        if ((RB_PARENT(tmp, field)))                                                               \
+            RB_AUGMENT(RB_PARENT(tmp, field));                                                     \
+    } while (/*CONSTCOND*/ 0)
+
+/* Generates prototypes and inline functions */
+#define RB_PROTOTYPE(name, type, field, cmp) RB_PROTOTYPE_INTERNAL(name, type, field, cmp, )
+#define RB_PROTOTYPE_STATIC(name, type, field, cmp)                                                \
+    RB_PROTOTYPE_INTERNAL(name, type, field, cmp, static)
+#define RB_PROTOTYPE_INTERNAL(name, type, field, cmp, attr)                                        \
+    RB_PROTOTYPE_INSERT_COLOR(name, type, attr);                                                   \
+    RB_PROTOTYPE_REMOVE_COLOR(name, type, attr);                                                   \
+    RB_PROTOTYPE_INSERT(name, type, attr);                                                         \
+    RB_PROTOTYPE_REMOVE(name, type, attr);                                                         \
+    RB_PROTOTYPE_FIND(name, type, attr);                                                           \
+    RB_PROTOTYPE_NFIND(name, type, attr);                                                          \
+    RB_PROTOTYPE_FIND_LIGHT(name, type, attr);                                                     \
+    RB_PROTOTYPE_NFIND_LIGHT(name, type, attr);                                                    \
+    RB_PROTOTYPE_NEXT(name, type, attr);                                                           \
+    RB_PROTOTYPE_PREV(name, type, attr);                                                           \
+    RB_PROTOTYPE_MINMAX(name, type, attr);
+#define RB_PROTOTYPE_INSERT_COLOR(name, type, attr)                                                \
+    attr void name##_RB_INSERT_COLOR(struct name*, struct type*)
+#define RB_PROTOTYPE_REMOVE_COLOR(name, type, attr)                                                \
+    attr void name##_RB_REMOVE_COLOR(struct name*, struct type*, struct type*)
+#define RB_PROTOTYPE_REMOVE(name, type, attr)                                                      \
+    attr struct type* name##_RB_REMOVE(struct name*, struct type*)
+#define RB_PROTOTYPE_INSERT(name, type, attr)                                                      \
+    attr struct type* name##_RB_INSERT(struct name*, struct type*)
+#define RB_PROTOTYPE_FIND(name, type, attr)                                                        \
+    attr struct type* name##_RB_FIND(struct name*, struct type*)
+#define RB_PROTOTYPE_NFIND(name, type, attr)                                                       \
+    attr struct type* name##_RB_NFIND(struct name*, struct type*)
+#define RB_PROTOTYPE_FIND_LIGHT(name, type, attr)                                                  \
+    attr struct type* name##_RB_FIND_LIGHT(struct name*, const void*)
+#define RB_PROTOTYPE_NFIND_LIGHT(name, type, attr)                                                 \
+    attr struct type* name##_RB_NFIND_LIGHT(struct name*, const void*)
+#define RB_PROTOTYPE_NEXT(name, type, attr) attr struct type* name##_RB_NEXT(struct type*)
+#define RB_PROTOTYPE_PREV(name, type, attr) attr struct type* name##_RB_PREV(struct type*)
+#define RB_PROTOTYPE_MINMAX(name, type, attr) attr struct type* name##_RB_MINMAX(struct name*, int)
+
+/* Main rb operation.
+ * Moves node close to the key of elm to top
+ */
+#define RB_GENERATE_WITHOUT_COMPARE(name, type, field)                                             \
+    RB_GENERATE_WITHOUT_COMPARE_INTERNAL(name, type, field, )
+#define RB_GENERATE_WITHOUT_COMPARE_STATIC(name, type, field)                                      \
+    RB_GENERATE_WITHOUT_COMPARE_INTERNAL(name, type, field, static)
+#define RB_GENERATE_WITHOUT_COMPARE_INTERNAL(name, type, field, attr)                              \
+    RB_GENERATE_REMOVE_COLOR(name, type, field, attr)                                              \
+    RB_GENERATE_REMOVE(name, type, field, attr)                                                    \
+    RB_GENERATE_NEXT(name, type, field, attr)                                                      \
+    RB_GENERATE_PREV(name, type, field, attr)                                                      \
+    RB_GENERATE_MINMAX(name, type, field, attr)
+
+#define RB_GENERATE_WITH_COMPARE(name, type, field, cmp, lcmp)                                     \
+    RB_GENERATE_WITH_COMPARE_INTERNAL(name, type, field, cmp, lcmp, )
+#define RB_GENERATE_WITH_COMPARE_STATIC(name, type, field, cmp, lcmp)                              \
+    RB_GENERATE_WITH_COMPARE_INTERNAL(name, type, field, cmp, lcmp, static)
+#define RB_GENERATE_WITH_COMPARE_INTERNAL(name, type, field, cmp, lcmp, attr)                      \
+    RB_GENERATE_INSERT_COLOR(name, type, field, attr)                                              \
+    RB_GENERATE_INSERT(name, type, field, cmp, attr)                                               \
+    RB_GENERATE_FIND(name, type, field, cmp, attr)                                                 \
+    RB_GENERATE_NFIND(name, type, field, cmp, attr)                                                \
+    RB_GENERATE_FIND_LIGHT(name, type, field, lcmp, attr)                                          \
+    RB_GENERATE_NFIND_LIGHT(name, type, field, lcmp, attr)
+
+#define RB_GENERATE_ALL(name, type, field, cmp) RB_GENERATE_ALL_INTERNAL(name, type, field, cmp, )
+#define RB_GENERATE_ALL_STATIC(name, type, field, cmp)                                             \
+    RB_GENERATE_ALL_INTERNAL(name, type, field, cmp, static)
+#define RB_GENERATE_ALL_INTERNAL(name, type, field, cmp, attr)                                     \
+    RB_GENERATE_WITHOUT_COMPARE_INTERNAL(name, type, field, attr)                                  \
+    RB_GENERATE_WITH_COMPARE_INTERNAL(name, type, field, cmp, attr)
+
+#define RB_GENERATE_INSERT_COLOR(name, type, field, attr)                                          \
+    attr void name##_RB_INSERT_COLOR(struct name* head, struct type* elm) {                        \
+        struct type *parent, *gparent, *tmp;                                                       \
+        while ((parent = RB_PARENT(elm, field)) != NULL && RB_COLOR(parent, field) == RB_RED) {    \
+            gparent = RB_PARENT(parent, field);                                                    \
+            if (parent == RB_LEFT(gparent, field)) {                                               \
+                tmp = RB_RIGHT(gparent, field);                                                    \
+                if (tmp && RB_COLOR(tmp, field) == RB_RED) {                                       \
+                    RB_COLOR(tmp, field) = RB_BLACK;                                               \
+                    RB_SET_BLACKRED(parent, gparent, field);                                       \
+                    elm = gparent;                                                                 \
+                    continue;                                                                      \
+                }                                                                                  \
+                if (RB_RIGHT(parent, field) == elm) {                                              \
+                    RB_ROTATE_LEFT(head, parent, tmp, field);                                      \
+                    tmp = parent;                                                                  \
+                    parent = elm;                                                                  \
+                    elm = tmp;                                                                     \
+                }                                                                                  \
+                RB_SET_BLACKRED(parent, gparent, field);                                           \
+                RB_ROTATE_RIGHT(head, gparent, tmp, field);                                        \
+            } else {                                                                               \
+                tmp = RB_LEFT(gparent, field);                                                     \
+                if (tmp && RB_COLOR(tmp, field) == RB_RED) {                                       \
+                    RB_COLOR(tmp, field) = RB_BLACK;                                               \
+                    RB_SET_BLACKRED(parent, gparent, field);                                       \
+                    elm = gparent;                                                                 \
+                    continue;                                                                      \
+                }                                                                                  \
+                if (RB_LEFT(parent, field) == elm) {                                               \
+                    RB_ROTATE_RIGHT(head, parent, tmp, field);                                     \
+                    tmp = parent;                                                                  \
+                    parent = elm;                                                                  \
+                    elm = tmp;                                                                     \
+                }                                                                                  \
+                RB_SET_BLACKRED(parent, gparent, field);                                           \
+                RB_ROTATE_LEFT(head, gparent, tmp, field);                                         \
+            }                                                                                      \
+        }                                                                                          \
+        RB_COLOR(head->rbh_root, field) = RB_BLACK;                                                \
+    }
+
+#define RB_GENERATE_REMOVE_COLOR(name, type, field, attr)                                          \
+    attr void name##_RB_REMOVE_COLOR(struct name* head, struct type* parent, struct type* elm) {   \
+        struct type* tmp;                                                                          \
+        while ((elm == NULL || RB_COLOR(elm, field) == RB_BLACK) && elm != RB_ROOT(head)) {        \
+            if (RB_LEFT(parent, field) == elm) {                                                   \
+                tmp = RB_RIGHT(parent, field);                                                     \
+                if (RB_COLOR(tmp, field) == RB_RED) {                                              \
+                    RB_SET_BLACKRED(tmp, parent, field);                                           \
+                    RB_ROTATE_LEFT(head, parent, tmp, field);                                      \
+                    tmp = RB_RIGHT(parent, field);                                                 \
+                }                                                                                  \
+                if ((RB_LEFT(tmp, field) == NULL ||                                                \
+                     RB_COLOR(RB_LEFT(tmp, field), field) == RB_BLACK) &&                          \
+                    (RB_RIGHT(tmp, field) == NULL ||                                               \
+                     RB_COLOR(RB_RIGHT(tmp, field), field) == RB_BLACK)) {                         \
+                    RB_COLOR(tmp, field) = RB_RED;                                                 \
+                    elm = parent;                                                                  \
+                    parent = RB_PARENT(elm, field);                                                \
+                } else {                                                                           \
+                    if (RB_RIGHT(tmp, field) == NULL ||                                            \
+                        RB_COLOR(RB_RIGHT(tmp, field), field) == RB_BLACK) {                       \
+                        struct type* oleft;                                                        \
+                        if ((oleft = RB_LEFT(tmp, field)) != NULL)                                 \
+                            RB_COLOR(oleft, field) = RB_BLACK;                                     \
+                        RB_COLOR(tmp, field) = RB_RED;                                             \
+                        RB_ROTATE_RIGHT(head, tmp, oleft, field);                                  \
+                        tmp = RB_RIGHT(parent, field);                                             \
+                    }                                                                              \
+                    RB_COLOR(tmp, field) = RB_COLOR(parent, field);                                \
+                    RB_COLOR(parent, field) = RB_BLACK;                                            \
+                    if (RB_RIGHT(tmp, field))                                                      \
+                        RB_COLOR(RB_RIGHT(tmp, field), field) = RB_BLACK;                          \
+                    RB_ROTATE_LEFT(head, parent, tmp, field);                                      \
+                    elm = RB_ROOT(head);                                                           \
+                    break;                                                                         \
+                }                                                                                  \
+            } else {                                                                               \
+                tmp = RB_LEFT(parent, field);                                                      \
+                if (RB_COLOR(tmp, field) == RB_RED) {                                              \
+                    RB_SET_BLACKRED(tmp, parent, field);                                           \
+                    RB_ROTATE_RIGHT(head, parent, tmp, field);                                     \
+                    tmp = RB_LEFT(parent, field);                                                  \
+                }                                                                                  \
+                if ((RB_LEFT(tmp, field) == NULL ||                                                \
+                     RB_COLOR(RB_LEFT(tmp, field), field) == RB_BLACK) &&                          \
+                    (RB_RIGHT(tmp, field) == NULL ||                                               \
+                     RB_COLOR(RB_RIGHT(tmp, field), field) == RB_BLACK)) {                         \
+                    RB_COLOR(tmp, field) = RB_RED;                                                 \
+                    elm = parent;                                                                  \
+                    parent = RB_PARENT(elm, field);                                                \
+                } else {                                                                           \
+                    if (RB_LEFT(tmp, field) == NULL ||                                             \
+                        RB_COLOR(RB_LEFT(tmp, field), field) == RB_BLACK) {                        \
+                        struct type* oright;                                                       \
+                        if ((oright = RB_RIGHT(tmp, field)) != NULL)                               \
+                            RB_COLOR(oright, field) = RB_BLACK;                                    \
+                        RB_COLOR(tmp, field) = RB_RED;                                             \
+                        RB_ROTATE_LEFT(head, tmp, oright, field);                                  \
+                        tmp = RB_LEFT(parent, field);                                              \
+                    }                                                                              \
+                    RB_COLOR(tmp, field) = RB_COLOR(parent, field);                                \
+                    RB_COLOR(parent, field) = RB_BLACK;                                            \
+                    if (RB_LEFT(tmp, field))                                                       \
+                        RB_COLOR(RB_LEFT(tmp, field), field) = RB_BLACK;                           \
+                    RB_ROTATE_RIGHT(head, parent, tmp, field);                                     \
+                    elm = RB_ROOT(head);                                                           \
+                    break;                                                                         \
+                }                                                                                  \
+            }                                                                                      \
+        }                                                                                          \
+        if (elm)                                                                                   \
+            RB_COLOR(elm, field) = RB_BLACK;                                                       \
+    }
+
+#define RB_GENERATE_REMOVE(name, type, field, attr)                                                \
+    attr struct type* name##_RB_REMOVE(struct name* head, struct type* elm) {                      \
+        struct type *child, *parent, *old = elm;                                                   \
+        int color;                                                                                 \
+        if (RB_LEFT(elm, field) == NULL)                                                           \
+            child = RB_RIGHT(elm, field);                                                          \
+        else if (RB_RIGHT(elm, field) == NULL)                                                     \
+            child = RB_LEFT(elm, field);                                                           \
+        else {                                                                                     \
+            struct type* left;                                                                     \
+            elm = RB_RIGHT(elm, field);                                                            \
+            while ((left = RB_LEFT(elm, field)) != NULL)                                           \
+                elm = left;                                                                        \
+            child = RB_RIGHT(elm, field);                                                          \
+            parent = RB_PARENT(elm, field);                                                        \
+            color = RB_COLOR(elm, field);                                                          \
+            if (child)                                                                             \
+                RB_PARENT(child, field) = parent;                                                  \
+            if (parent) {                                                                          \
+                if (RB_LEFT(parent, field) == elm)                                                 \
+                    RB_LEFT(parent, field) = child;                                                \
+                else                                                                               \
+                    RB_RIGHT(parent, field) = child;                                               \
+                RB_AUGMENT(parent);                                                                \
+            } else                                                                                 \
+                RB_ROOT(head) = child;                                                             \
+            if (RB_PARENT(elm, field) == old)                                                      \
+                parent = elm;                                                                      \
+            (elm)->field = (old)->field;                                                           \
+            if (RB_PARENT(old, field)) {                                                           \
+                if (RB_LEFT(RB_PARENT(old, field), field) == old)                                  \
+                    RB_LEFT(RB_PARENT(old, field), field) = elm;                                   \
+                else                                                                               \
+                    RB_RIGHT(RB_PARENT(old, field), field) = elm;                                  \
+                RB_AUGMENT(RB_PARENT(old, field));                                                 \
+            } else                                                                                 \
+                RB_ROOT(head) = elm;                                                               \
+            RB_PARENT(RB_LEFT(old, field), field) = elm;                                           \
+            if (RB_RIGHT(old, field))                                                              \
+                RB_PARENT(RB_RIGHT(old, field), field) = elm;                                      \
+            if (parent) {                                                                          \
+                left = parent;                                                                     \
+                do {                                                                               \
+                    RB_AUGMENT(left);                                                              \
+                } while ((left = RB_PARENT(left, field)) != NULL);                                 \
+            }                                                                                      \
+            goto color;                                                                            \
+        }                                                                                          \
+        parent = RB_PARENT(elm, field);                                                            \
+        color = RB_COLOR(elm, field);                                                              \
+        if (child)                                                                                 \
+            RB_PARENT(child, field) = parent;                                                      \
+        if (parent) {                                                                              \
+            if (RB_LEFT(parent, field) == elm)                                                     \
+                RB_LEFT(parent, field) = child;                                                    \
+            else                                                                                   \
+                RB_RIGHT(parent, field) = child;                                                   \
+            RB_AUGMENT(parent);                                                                    \
+        } else                                                                                     \
+            RB_ROOT(head) = child;                                                                 \
+    color:                                                                                         \
+        if (color == RB_BLACK)                                                                     \
+            name##_RB_REMOVE_COLOR(head, parent, child);                                           \
+        return (old);                                                                              \
+    }
+
+#define RB_GENERATE_INSERT(name, type, field, cmp, attr)                                           \
+    /* Inserts a node into the RB tree */                                                          \
+    attr struct type* name##_RB_INSERT(struct name* head, struct type* elm) {                      \
+        struct type* tmp;                                                                          \
+        struct type* parent = NULL;                                                                \
+        int comp = 0;                                                                              \
+        tmp = RB_ROOT(head);                                                                       \
+        while (tmp) {                                                                              \
+            parent = tmp;                                                                          \
+            comp = (cmp)(elm, parent);                                                             \
+            if (comp < 0)                                                                          \
+                tmp = RB_LEFT(tmp, field);                                                         \
+            else if (comp > 0)                                                                     \
+                tmp = RB_RIGHT(tmp, field);                                                        \
+            else                                                                                   \
+                return (tmp);                                                                      \
+        }                                                                                          \
+        RB_SET(elm, parent, field);                                                                \
+        if (parent != NULL) {                                                                      \
+            if (comp < 0)                                                                          \
+                RB_LEFT(parent, field) = elm;                                                      \
+            else                                                                                   \
+                RB_RIGHT(parent, field) = elm;                                                     \
+            RB_AUGMENT(parent);                                                                    \
+        } else                                                                                     \
+            RB_ROOT(head) = elm;                                                                   \
+        name##_RB_INSERT_COLOR(head, elm);                                                         \
+        return (NULL);                                                                             \
+    }
+
+#define RB_GENERATE_FIND(name, type, field, cmp, attr)                                             \
+    /* Finds the node with the same key as elm */                                                  \
+    attr struct type* name##_RB_FIND(struct name* head, struct type* elm) {                        \
+        struct type* tmp = RB_ROOT(head);                                                          \
+        int comp;                                                                                  \
+        while (tmp) {                                                                              \
+            comp = cmp(elm, tmp);                                                                  \
+            if (comp < 0)                                                                          \
+                tmp = RB_LEFT(tmp, field);                                                         \
+            else if (comp > 0)                                                                     \
+                tmp = RB_RIGHT(tmp, field);                                                        \
+            else                                                                                   \
+                return (tmp);                                                                      \
+        }                                                                                          \
+        return (NULL);                                                                             \
+    }
+
+#define RB_GENERATE_NFIND(name, type, field, cmp, attr)                                            \
+    /* Finds the first node greater than or equal to the search key */                             \
+    attr struct type* name##_RB_NFIND(struct name* head, struct type* elm) {                       \
+        struct type* tmp = RB_ROOT(head);                                                          \
+        struct type* res = NULL;                                                                   \
+        int comp;                                                                                  \
+        while (tmp) {                                                                              \
+            comp = cmp(elm, tmp);                                                                  \
+            if (comp < 0) {                                                                        \
+                res = tmp;                                                                         \
+                tmp = RB_LEFT(tmp, field);                                                         \
+            } else if (comp > 0)                                                                   \
+                tmp = RB_RIGHT(tmp, field);                                                        \
+            else                                                                                   \
+                return (tmp);                                                                      \
+        }                                                                                          \
+        return (res);                                                                              \
+    }
+
+#define RB_GENERATE_FIND_LIGHT(name, type, field, lcmp, attr)                                      \
+    /* Finds the node with the same key as elm */                                                  \
+    attr struct type* name##_RB_FIND_LIGHT(struct name* head, const void* lelm) {                  \
+        struct type* tmp = RB_ROOT(head);                                                          \
+        int comp;                                                                                  \
+        while (tmp) {                                                                              \
+            comp = lcmp(lelm, tmp);                                                                \
+            if (comp < 0)                                                                          \
+                tmp = RB_LEFT(tmp, field);                                                         \
+            else if (comp > 0)                                                                     \
+                tmp = RB_RIGHT(tmp, field);                                                        \
+            else                                                                                   \
+                return (tmp);                                                                      \
+        }                                                                                          \
+        return (NULL);                                                                             \
+    }
+
+#define RB_GENERATE_NFIND_LIGHT(name, type, field, lcmp, attr)                                     \
+    /* Finds the first node greater than or equal to the search key */                             \
+    attr struct type* name##_RB_NFIND_LIGHT(struct name* head, const void* lelm) {                 \
+        struct type* tmp = RB_ROOT(head);                                                          \
+        struct type* res = NULL;                                                                   \
+        int comp;                                                                                  \
+        while (tmp) {                                                                              \
+            comp = lcmp(lelm, tmp);                                                                \
+            if (comp < 0) {                                                                        \
+                res = tmp;                                                                         \
+                tmp = RB_LEFT(tmp, field);                                                         \
+            } else if (comp > 0)                                                                   \
+                tmp = RB_RIGHT(tmp, field);                                                        \
+            else                                                                                   \
+                return (tmp);                                                                      \
+        }                                                                                          \
+        return (res);                                                                              \
+    }
+
+#define RB_GENERATE_NEXT(name, type, field, attr)                                                  \
+    /* ARGSUSED */                                                                                 \
+    attr struct type* name##_RB_NEXT(struct type* elm) {                                           \
+        if (RB_RIGHT(elm, field)) {                                                                \
+            elm = RB_RIGHT(elm, field);                                                            \
+            while (RB_LEFT(elm, field))                                                            \
+                elm = RB_LEFT(elm, field);                                                         \
+        } else {                                                                                   \
+            if (RB_PARENT(elm, field) && (elm == RB_LEFT(RB_PARENT(elm, field), field)))           \
+                elm = RB_PARENT(elm, field);                                                       \
+            else {                                                                                 \
+                while (RB_PARENT(elm, field) && (elm == RB_RIGHT(RB_PARENT(elm, field), field)))   \
+                    elm = RB_PARENT(elm, field);                                                   \
+                elm = RB_PARENT(elm, field);                                                       \
+            }                                                                                      \
+        }                                                                                          \
+        return (elm);                                                                              \
+    }
+
+#define RB_GENERATE_PREV(name, type, field, attr)                                                  \
+    /* ARGSUSED */                                                                                 \
+    attr struct type* name##_RB_PREV(struct type* elm) {                                           \
+        if (RB_LEFT(elm, field)) {                                                                 \
+            elm = RB_LEFT(elm, field);                                                             \
+            while (RB_RIGHT(elm, field))                                                           \
+                elm = RB_RIGHT(elm, field);                                                        \
+        } else {                                                                                   \
+            if (RB_PARENT(elm, field) && (elm == RB_RIGHT(RB_PARENT(elm, field), field)))          \
+                elm = RB_PARENT(elm, field);                                                       \
+            else {                                                                                 \
+                while (RB_PARENT(elm, field) && (elm == RB_LEFT(RB_PARENT(elm, field), field)))    \
+                    elm = RB_PARENT(elm, field);                                                   \
+                elm = RB_PARENT(elm, field);                                                       \
+            }                                                                                      \
+        }                                                                                          \
+        return (elm);                                                                              \
+    }
+
+#define RB_GENERATE_MINMAX(name, type, field, attr)                                                \
+    attr struct type* name##_RB_MINMAX(struct name* head, int val) {                               \
+        struct type* tmp = RB_ROOT(head);                                                          \
+        struct type* parent = NULL;                                                                \
+        while (tmp) {                                                                              \
+            parent = tmp;                                                                          \
+            if (val < 0)                                                                           \
+                tmp = RB_LEFT(tmp, field);                                                         \
+            else                                                                                   \
+                tmp = RB_RIGHT(tmp, field);                                                        \
+        }                                                                                          \
+        return (parent);                                                                           \
+    }
+
+#define RB_NEGINF -1
+#define RB_INF 1
+
+#define RB_INSERT(name, x, y) name##_RB_INSERT(x, y)
+#define RB_REMOVE(name, x, y) name##_RB_REMOVE(x, y)
+#define RB_FIND(name, x, y) name##_RB_FIND(x, y)
+#define RB_NFIND(name, x, y) name##_RB_NFIND(x, y)
+#define RB_FIND_LIGHT(name, x, y) name##_RB_FIND_LIGHT(x, y)
+#define RB_NFIND_LIGHT(name, x, y) name##_RB_NFIND_LIGHT(x, y)
+#define RB_NEXT(name, x, y) name##_RB_NEXT(y)
+#define RB_PREV(name, x, y) name##_RB_PREV(y)
+#define RB_MIN(name, x) name##_RB_MINMAX(x, RB_NEGINF)
+#define RB_MAX(name, x) name##_RB_MINMAX(x, RB_INF)
+
+#define RB_FOREACH(x, name, head)                                                                  \
+    for ((x) = RB_MIN(name, head); (x) != NULL; (x) = name##_RB_NEXT(x))
+
+#define RB_FOREACH_FROM(x, name, y)                                                                \
+    for ((x) = (y); ((x) != NULL) && ((y) = name##_RB_NEXT(x), (x) != NULL); (x) = (y))
+
+#define RB_FOREACH_SAFE(x, name, head, y)                                                          \
+    for ((x) = RB_MIN(name, head); ((x) != NULL) && ((y) = name##_RB_NEXT(x), (x) != NULL);        \
+         (x) = (y))
+
+#define RB_FOREACH_REVERSE(x, name, head)                                                          \
+    for ((x) = RB_MAX(name, head); (x) != NULL; (x) = name##_RB_PREV(x))
+
+#define RB_FOREACH_REVERSE_FROM(x, name, y)                                                        \
+    for ((x) = (y); ((x) != NULL) && ((y) = name##_RB_PREV(x), (x) != NULL); (x) = (y))
+
+#define RB_FOREACH_REVERSE_SAFE(x, name, head, y)                                                  \
+    for ((x) = RB_MAX(name, head); ((x) != NULL) && ((y) = name##_RB_PREV(x), (x) != NULL);        \
+         (x) = (y))
+
+#endif /* _SYS_TREE_H_ */