From 3d141195362dc7557d09deab5b25c3647ee4764e Mon Sep 17 00:00:00 2001
From: fallenoak <git@fallenoak.me>
Date: Mon, 27 Mar 2023 17:28:51 -0500
Subject: [PATCH] feat(hash): add synchronized export table template

---
 storm/Hash.hpp                        |  1 +
 storm/hash/TSExportTableSyncReuse.hpp | 87 +++++++++++++++++++++++++++
 test/Hash.cpp                         | 44 ++++++++++++++
 3 files changed, 132 insertions(+)
 create mode 100644 storm/hash/TSExportTableSyncReuse.hpp

diff --git a/storm/Hash.hpp b/storm/Hash.hpp
index 4bc513b..e0b966f 100644
--- a/storm/Hash.hpp
+++ b/storm/Hash.hpp
@@ -3,6 +3,7 @@
 
 #include "storm/hash/Hashkey.hpp"
 #include "storm/hash/TSExportTableSimpleReuse.hpp"
+#include "storm/hash/TSExportTableSyncReuse.hpp"
 #include "storm/hash/TSHashObject.hpp"
 #include "storm/hash/TSHashTable.hpp"
 #include "storm/hash/TSHashTableReuse.hpp"
diff --git a/storm/hash/TSExportTableSyncReuse.hpp b/storm/hash/TSExportTableSyncReuse.hpp
new file mode 100644
index 0000000..21fdb64
--- /dev/null
+++ b/storm/hash/TSExportTableSyncReuse.hpp
@@ -0,0 +1,87 @@
+#ifndef STORM_HASH_TS_EXPORT_TABLE_SYNC_REUSE_HPP
+#define STORM_HASH_TS_EXPORT_TABLE_SYNC_REUSE_HPP
+
+#include "storm/hash/Hashkey.hpp"
+#include "storm/hash/TSExportTableSimpleReuse.hpp"
+
+template <class T, class THandle, class TLockedHandle, class TSync>
+class TSExportTableSyncReuse : public TSExportTableSimpleReuse<T, THandle> {
+    public:
+    // Virtual member functions
+    virtual ~TSExportTableSyncReuse() = default;
+
+    // Member functions
+    void Delete(THandle handle);
+    void DeleteUnlock(T* ptr, TLockedHandle lockedHandle);
+    T* Lock(THandle handle, TLockedHandle* lockedHandlePtr, int32_t forWriting);
+    T* NewLock(THandle* handlePtr, TLockedHandle* lockedHandlePtr);
+    void Unlock(TLockedHandle lockedHandle);
+
+    private:
+    // Member variables
+    TSync m_sync;
+
+    // Member functions
+    int32_t IsForWriting(TLockedHandle lockedHandle);
+    void SyncEnterLock(TLockedHandle* lockedHandlePtr, int32_t forWriting);
+    void SyncLeaveLock(TLockedHandle lockedHandle);
+};
+
+template <class T, class THandle, class TLockedHandle, class TSync>
+void TSExportTableSyncReuse<T, THandle, TLockedHandle, TSync>::Delete(THandle handle) {
+    TLockedHandle lockedHandle;
+    auto ptr = this->Lock(handle, &lockedHandle, 1);
+    this->DeleteUnlock(ptr, lockedHandle);
+}
+
+template <class T, class THandle, class TLockedHandle, class TSync>
+void TSExportTableSyncReuse<T, THandle, TLockedHandle, TSync>::DeleteUnlock(T* ptr, TLockedHandle lockedHandle) {
+    this->TSExportTableSimpleReuse<T, THandle>::Delete(ptr);
+    this->Unlock(lockedHandle);
+}
+
+template <class T, class THandle, class TLockedHandle, class TSync>
+int32_t TSExportTableSyncReuse<T, THandle, TLockedHandle, TSync>::IsForWriting(TLockedHandle lockedHandle) {
+    return reinterpret_cast<intptr_t>(lockedHandle) == 1;
+}
+
+template <class T, class THandle, class TLockedHandle, class TSync>
+T* TSExportTableSyncReuse<T, THandle, TLockedHandle, TSync>::Lock(THandle handle, TLockedHandle* lockedHandlePtr, int32_t forWriting) {
+    this->SyncEnterLock(lockedHandlePtr, forWriting);
+
+    auto ptr = this->Ptr(handle);
+
+    if (!ptr) {
+        this->SyncLeaveLock(*lockedHandlePtr);
+        *lockedHandlePtr = nullptr;
+        return nullptr;
+    }
+
+    return ptr;
+}
+
+template <class T, class THandle, class TLockedHandle, class TSync>
+T* TSExportTableSyncReuse<T, THandle, TLockedHandle, TSync>::NewLock(THandle* handlePtr, TLockedHandle* lockedHandlePtr) {
+    this->SyncEnterLock(lockedHandlePtr, 1);
+    return this->New(handlePtr);
+}
+
+template <class T, class THandle, class TLockedHandle, class TSync>
+void TSExportTableSyncReuse<T, THandle, TLockedHandle, TSync>::SyncEnterLock(TLockedHandle* lockedHandlePtr, int32_t forWriting) {
+    this->m_sync.Enter(forWriting);
+    *lockedHandlePtr = reinterpret_cast<TLockedHandle>(forWriting ? 1 : -1);
+}
+
+template <class T, class THandle, class TLockedHandle, class TSync>
+void TSExportTableSyncReuse<T, THandle, TLockedHandle, TSync>::SyncLeaveLock(TLockedHandle lockedHandle) {
+    if (lockedHandle) {
+        this->m_sync.Leave(this->IsForWriting(lockedHandle));
+    }
+}
+
+template <class T, class THandle, class TLockedHandle, class TSync>
+void TSExportTableSyncReuse<T, THandle, TLockedHandle, TSync>::Unlock(TLockedHandle lockedHandle) {
+    this->SyncLeaveLock(lockedHandle);
+}
+
+#endif
diff --git a/test/Hash.cpp b/test/Hash.cpp
index 76b4ab3..155cb7c 100644
--- a/test/Hash.cpp
+++ b/test/Hash.cpp
@@ -1,4 +1,5 @@
 #include "storm/Hash.hpp"
+#include "storm/Thread.hpp"
 #include "test/Test.hpp"
 
 struct TestHashObject : TSHashObject<TestHashObject, HASHKEY_STRI> {
@@ -11,6 +12,8 @@ struct TestExportObject : TSHashObject<TestHashObject, HASHKEY_NONE> {
 
 typedef void* TestExportObjectHandle;
 
+typedef void* TestExportLockedHandle;
+
 TEST_CASE("TSHashTable", "[hash]") {
     SECTION("constructs correctly") {
         TSHashTable<TestHashObject, HASHKEY_STRI> hashTable;
@@ -117,3 +120,44 @@ TEST_CASE("TSExportTableSimpleReuse::Delete", "[hash]") {
         REQUIRE(exportTable.Ptr(handle) == nullptr);
     }
 }
+
+TEST_CASE("TSExportTableSyncReuse", "[hash]") {
+    SECTION("constructs correctly") {
+        TSExportTableSyncReuse<TestExportObject, TestExportObjectHandle, TestExportLockedHandle, CCritSect> exportTable;
+        REQUIRE(exportTable.Head() == nullptr);
+    }
+}
+
+TEST_CASE("TSExportTableSyncReuse::NewLock", "[hash]") {
+    SECTION("returns a new object, handle, and locked handle") {
+        TSExportTableSyncReuse<TestExportObject, TestExportObjectHandle, TestExportLockedHandle, CCritSect> exportTable;
+        TestExportObjectHandle handle;
+        TestExportLockedHandle lockedHandle;
+        auto object = exportTable.NewLock(&handle, &lockedHandle);
+        exportTable.Unlock(lockedHandle);
+
+        REQUIRE(handle != nullptr);
+        REQUIRE(lockedHandle != nullptr);
+        REQUIRE(object != nullptr);
+        REQUIRE(object != handle);
+        REQUIRE(exportTable.Head() == object);
+        REQUIRE(exportTable.Ptr(handle) == object);
+    }
+}
+
+TEST_CASE("TSExportTableSyncReuse::Delete", "[hash]") {
+    SECTION("deletes object from export table") {
+        TSExportTableSyncReuse<TestExportObject, TestExportObjectHandle, TestExportLockedHandle, CCritSect> exportTable;
+        TestExportObjectHandle handle;
+        TestExportLockedHandle lockedHandle;
+        auto object = exportTable.NewLock(&handle, &lockedHandle);
+        exportTable.Unlock(lockedHandle);
+        exportTable.Delete(handle);
+
+        REQUIRE(handle != nullptr);
+        REQUIRE(object != nullptr);
+        REQUIRE(object != handle);
+        REQUIRE(exportTable.Head() == nullptr);
+        REQUIRE(exportTable.Ptr(handle) == nullptr);
+    }
+}