optimize: Add conditional variable to LuaResult (#162)

Implementing TODO for optimization I saw in the code.

include/TLuaEngine.h

@@ -41,7 +41,14 @@ struct TLuaResult {
     sol::object Result { sol::lua_nil };
     TLuaStateId StateId;
     std::string Function;
-    // TODO: Add condition_variable
+    std::shared_ptr<std::mutex> ReadyMutex {
+        std::make_shared<std::mutex>()
+    };
+    std::shared_ptr<std::condition_variable> ReadyCondition {
+        std::make_shared<std::condition_variable>()
+    };
+
+    void MarkAsReady();
     void WaitUntilReady();
 };
 
@@ -98,8 +105,8 @@ public:
         return mLuaStates.size();
     }
     std::vector<std::string> GetLuaStateNames() {
-        std::vector<std::string> names{};
+        std::vector<std::string> names {};
-        for(auto const& [stateId, _ ] : mLuaStates) {
+        for (auto const& [stateId, _] : mLuaStates) {
             names.push_back(stateId);
         }
         return names;

src/TConsole.cpp

@@ -606,9 +606,7 @@ TConsole::TConsole() {
                     HandleLuaInternalCommand(cmd.substr(1));
                 } else {
                     auto Future = mLuaEngine->EnqueueScript(mStateId, { std::make_shared<std::string>(TrimmedCmd), "", "" });
-                    while (!Future->Ready) {
+                    Future->WaitUntilReady();
-                        std::this_thread::yield(); // TODO: Add a timeout
-                    }
                     if (Future->Error) {
                         beammp_lua_error("error in " + mStateId + ": " + Future->ErrorMessage);
                     }

src/TLuaEngine.cpp

@@ -286,6 +286,7 @@ void TLuaEngine::WaitForAll(std::vector<std::shared_ptr<TLuaResult>>& Results, c
         bool Cancelled = false;
         size_t ms = 0;
         std::set<std::string> WarnedResults;
+
         while (!Result->Ready && !Cancelled) {
             std::this_thread::sleep_for(std::chrono::milliseconds(10));
             ms += 10;
@@ -300,6 +301,7 @@ void TLuaEngine::WaitForAll(std::vector<std::shared_ptr<TLuaResult>>& Results, c
                 }
             }
         }
+
         if (Cancelled) {
             beammp_lua_warn("'" + Result->Function + "' in '" + Result->StateId + "' failed to execute in time and was not waited for. It may still finish executing at a later time.");
             LuaAPI::MP::Engine->ReportErrors({ Result });
@@ -425,7 +427,7 @@ sol::table TLuaEngine::StateThreadData::Lua_TriggerGlobalEvent(const std::string
                 Result->Error = true;
                 Result->ErrorMessage = "Function result in TriggerGlobalEvent was invalid";
             }
-            Result->Ready = true;
+            Result->MarkAsReady();
             Return.push_back(Result);
         }
     }
@@ -955,7 +957,7 @@ void TLuaEngine::StateThreadData::operator()() {
                     sol::error Err = Res;
                     S.second->ErrorMessage = Err.what();
                 }
-                S.second->Ready = true;
+                S.second->MarkAsReady();
             }
         }
         { // StateFunctionQueue Scope
@@ -1016,11 +1018,11 @@ void TLuaEngine::StateThreadData::operator()() {
                         sol::error Err = Res;
                         Result->ErrorMessage = Err.what();
                     }
-                    Result->Ready = true;
+                    Result->MarkAsReady();
                 } else {
                     Result->Error = true;
                     Result->ErrorMessage = BeamMPFnNotFoundError; // special error kind that we can ignore later
-                    Result->Ready = true;
+                    Result->MarkAsReady();
                 }
             }
         }
@@ -1070,11 +1072,19 @@ void TLuaEngine::StateThreadData::AddPath(const fs::path& Path) {
     mPaths.push(Path);
 }
 
-void TLuaResult::WaitUntilReady() {
+void TLuaResult::MarkAsReady() {
-    while (!Ready) {
+    {
-        std::this_thread::yield();
+        std::lock_guard<std::mutex> readyLock(*this->ReadyMutex);
-        std::this_thread::sleep_for(std::chrono::milliseconds(10));
+        this->Ready = true;
     }
+    this->ReadyCondition->notify_all();
+}
+
+void TLuaResult::WaitUntilReady() {
+    std::unique_lock readyLock(*this->ReadyMutex);
+    // wait if not ready yet
+    if(!this->Ready)
+        this->ReadyCondition->wait(readyLock);
 }
 
 TLuaChunk::TLuaChunk(std::shared_ptr<std::string> Content, std::string FileName, std::string PluginPath)