From ba55476567b522e987337995f87a1055c3f901e5 Mon Sep 17 00:00:00 2001
From: fallenoak <git@fallenoak.me>
Date: Sun, 1 Jan 2023 15:47:52 -0600
Subject: [PATCH] feat(instance): add TInstanceId and TSingletonInstanceId

---
 common/Instance.hpp                      |   7 ++
 common/instance/TInstanceId.hpp          |  14 +++
 common/instance/TInstanceIdTable.hpp     | 145 +++++++++++++++++++++++
 common/instance/TSingletonInstanceId.hpp |  14 +++
 4 files changed, 180 insertions(+)
 create mode 100644 common/Instance.hpp
 create mode 100644 common/instance/TInstanceId.hpp
 create mode 100644 common/instance/TInstanceIdTable.hpp
 create mode 100644 common/instance/TSingletonInstanceId.hpp

diff --git a/common/Instance.hpp b/common/Instance.hpp
new file mode 100644
index 0000000..e1a101a
--- /dev/null
+++ b/common/Instance.hpp
@@ -0,0 +1,7 @@
+#ifndef COMMON_INSTANCE_HPP
+#define COMMON_INSTANCE_HPP
+
+#include "common/instance/TInstanceId.hpp"
+#include "common/instance/TSingletonInstanceId.hpp"
+
+#endif
diff --git a/common/instance/TInstanceId.hpp b/common/instance/TInstanceId.hpp
new file mode 100644
index 0000000..e4562b3
--- /dev/null
+++ b/common/instance/TInstanceId.hpp
@@ -0,0 +1,14 @@
+#ifndef COMMON_INSTANCE_T_INSTANCE_ID_HPP
+#define COMMON_INSTANCE_T_INSTANCE_ID_HPP
+
+#include <cstdint>
+#include <storm/List.hpp>
+
+template <class T>
+class TInstanceId : public TSLinkedNode<T> {
+    public:
+    // Member variables
+    uint32_t m_id;
+};
+
+#endif
diff --git a/common/instance/TInstanceIdTable.hpp b/common/instance/TInstanceIdTable.hpp
new file mode 100644
index 0000000..815de60
--- /dev/null
+++ b/common/instance/TInstanceIdTable.hpp
@@ -0,0 +1,145 @@
+#ifndef COMMON_INSTANCE_T_INSTANCE_ID_TABLE_HPP
+#define COMMON_INSTANCE_T_INSTANCE_ID_TABLE_HPP
+
+#include <cstdint>
+#include <storm/List.hpp>
+#include <storm/Thread.hpp>
+
+#define INSTANCE_TABLE_SLOT_COUNT 8
+
+template <class T, size_t offset>
+class TInstanceIdTable {
+    public:
+    // Types
+    class Iterator {
+        public:
+        TInstanceIdTable<T, offset>* m_table;
+        int32_t m_slot;
+        T* m_next;
+    };
+
+    // Member variables
+    SCritSect m_idCritsect;
+    uint32_t m_id;
+    int32_t m_idWrapped;
+    CSRWLock m_idLock[INSTANCE_TABLE_SLOT_COUNT];
+    TSList<T, TSGetLink<T>> m_idList[INSTANCE_TABLE_SLOT_COUNT];
+
+    // Member functions
+    void Insert(T* instance);
+    T* Ptr(uint32_t id, int32_t lockMode, int32_t* findMask);
+    void Unlock(uint32_t slot, int32_t lockMode);
+
+    private:
+    uint32_t NextId();
+};
+
+template <class T, size_t offset>
+void TInstanceIdTable<T, offset>::Insert(T* instance) {
+    if (instance->m_id) {
+        return;
+    }
+
+    this->m_idCritsect.Enter();
+
+    auto id = this->NextId();
+
+    instance->m_id = id;
+
+    uint32_t slot = id & (INSTANCE_TABLE_SLOT_COUNT - 1);
+
+    auto idLock = &this->m_idLock[slot];
+
+    idLock->Enter(1);
+
+    this->m_idList[slot].LinkNode(instance, 2, nullptr);
+
+    idLock->Leave(1);
+
+    this->m_idCritsect.Leave();
+}
+
+template <class T, size_t offset>
+uint32_t TInstanceIdTable<T, offset>::NextId() {
+    uint32_t id;
+    int32_t exists;
+
+    do {
+        while (1) {
+            id = this->m_id + 1;
+
+            this->m_id++;
+
+            if (this->m_id != 0) {
+                break;
+            }
+
+            this->m_idWrapped = 1;
+        }
+
+        if (this->m_idWrapped == 0) {
+            break;
+        }
+
+        uint32_t slot = id & (INSTANCE_TABLE_SLOT_COUNT - 1);
+
+        auto idLock = &this->m_idLock[slot];
+
+        idLock->Enter(0);
+
+        exists = 0;
+
+        auto idList = &this->m_idList[slot];
+
+        auto node = idList->Head();
+
+        while (node) {
+            if (node->m_id == id) {
+                exists = 1;
+                break;
+            }
+
+            node = idList->Link(node)->Next();
+        }
+
+        idLock->Leave(0);
+    } while (exists);
+
+    return id;
+}
+
+template <class T, size_t offset>
+T* TInstanceIdTable<T, offset>::Ptr(uint32_t id, int32_t lockMode, int32_t* findMask) {
+    if (id) {
+        uint32_t slot = id & (INSTANCE_TABLE_SLOT_COUNT - 1);
+
+        auto idLock = &this->m_idLock[slot];
+
+        idLock->Enter(lockMode);
+
+        auto idList = &this->m_idList[slot];
+
+        auto node = idList->Head();
+
+        while (node) {
+            if (node->m_id == id) {
+                *findMask = slot + (lockMode != 0 ? INSTANCE_TABLE_SLOT_COUNT : 0);
+                return node;
+            }
+
+            node = idList->Link(node)->Next();
+        }
+
+        idLock->Leave(lockMode);
+    }
+
+    *findMask = -1;
+    return nullptr;
+}
+
+template <class T, size_t offset>
+void TInstanceIdTable<T, offset>::Unlock(uint32_t slot, int32_t lockMode) {
+    this->m_idLock[slot].Leave(lockMode);
+}
+
+#endif
diff --git a/common/instance/TSingletonInstanceId.hpp b/common/instance/TSingletonInstanceId.hpp
new file mode 100644
index 0000000..1aef572
--- /dev/null
+++ b/common/instance/TSingletonInstanceId.hpp
@@ -0,0 +1,14 @@
+#ifndef COMMON_INSTANCE_T_SINGLETON_INSTANCE_ID_HPP
+#define COMMON_INSTANCE_T_SINGLETON_INSTANCE_ID_HPP
+
+#include "common/instance/TInstanceId.hpp"
+#include "common/instance/TInstanceIdTable.hpp"
+
+template <class T, size_t offset>
+class TSingletonInstanceId : public TInstanceId<T> {
+    public:
+    // Static variables
+    static TInstanceIdTable<T, offset> s_idTable;
+};
+
+#endif