Use unique_ptr to handle lua state lifetime

components/CMakeLists.txt

@@ -59,7 +59,7 @@ list(APPEND COMPONENT_FILES "${OpenMW_BINARY_DIR}/${OSG_PLUGIN_CHECKER_CPP_FILE}
 
 add_component_dir (lua
     luastate scriptscontainer asyncpackage utilpackage serialization configuration l10n storage utf8
-    shapes/box inputactions yamlloader scripttracker
+    shapes/box inputactions yamlloader scripttracker luastateptr
     )
 
 add_component_dir (l10n

components/esm/luascripts.cpp

@@ -1,8 +1,9 @@
 #include "luascripts.hpp"
 
-#include "components/esm3/esmreader.hpp"
+#include <components/esm3/esmreader.hpp>
-#include "components/esm3/esmwriter.hpp"
+#include <components/esm3/esmwriter.hpp>
 
+#include <components/lua/luastateptr.hpp>
 #include <components/lua/serialization.hpp>
 
 // List of all records, that are related to Lua.
@@ -102,13 +103,16 @@ void ESM::LuaScriptsCfg::adjustRefNums(const ESMReader& esm)
             throw std::runtime_error("Incorrect contentFile index");
     };
 
-    lua_State* L = luaL_newstate();
+    LuaUtil::LuaStatePtr state(luaL_newstate());
+    if (state == nullptr)
+        throw std::runtime_error("Failed to create Lua runtime");
+
     LuaUtil::BasicSerializer serializer(adjustRefNumFn);
 
     auto adjustLuaData = [&](std::string& data) {
         if (data.empty())
             return;
-        sol::object luaData = LuaUtil::deserialize(L, data, &serializer);
+        sol::object luaData = LuaUtil::deserialize(state.get(), data, &serializer);
         data = LuaUtil::serialize(luaData, &serializer);
     };
 
@@ -123,7 +127,6 @@ void ESM::LuaScriptsCfg::adjustRefNums(const ESMReader& esm)
             refCfg.mRefnumContentFile = adjustRefNumFn(refCfg.mRefnumContentFile);
         }
     }
-    lua_close(L);
 }
 
 void ESM::LuaScriptsCfg::save(ESMWriter& esm) const

components/lua/luastate.cpp

@@ -11,6 +11,7 @@
 #include <components/files/conversion.hpp>
 #include <components/vfs/manager.hpp>
 
+#include "luastateptr.hpp"
 #include "scriptscontainer.hpp"
 #include "utf8.hpp"
 
@@ -151,37 +152,37 @@ namespace LuaUtil
         return newPtr;
     }
 
-    lua_State* LuaState::createLuaRuntime(LuaState* luaState)
+    LuaStatePtr LuaState::createLuaRuntime(LuaState* luaState)
     {
         if (sProfilerEnabled)
         {
             Log(Debug::Info) << "Initializing LuaUtil::LuaState with profiler";
-            lua_State* L = lua_newstate(&trackingAllocator, luaState);
+            LuaStatePtr state(lua_newstate(&trackingAllocator, luaState));
-            if (L)
+            if (state != nullptr)
-                return L;
+                return state;
-            else
+            sProfilerEnabled = false;
-            {
+            Log(Debug::Error) << "Failed to initialize LuaUtil::LuaState with custom allocator; disabling Lua profiler";
-                sProfilerEnabled = false;
-                Log(Debug::Error)
-                    << "Failed to initialize LuaUtil::LuaState with custom allocator; disabling Lua profiler";
-            }
         }
         Log(Debug::Info) << "Initializing LuaUtil::LuaState without profiler";
-        lua_State* L = luaL_newstate();
+        LuaStatePtr state(luaL_newstate());
-        if (!L)
+        if (state == nullptr)
-            throw std::runtime_error("Can't create Lua runtime");
+            throw std::runtime_error("Failed to create Lua runtime");
-        return L;
+        return state;
     }
 
     LuaState::LuaState(const VFS::Manager* vfs, const ScriptsConfiguration* conf, const LuaStateSettings& settings)
         : mSettings(settings)
-        , mLuaHolder(createLuaRuntime(this))
+        , mLuaState([&] {
-        , mSol(mLuaHolder.get())
+            LuaStatePtr state = createLuaRuntime(this);
+            sol::set_default_state(state.get());
+            return state;
+        }())
+        , mSol(mLuaState.get())
         , mConf(conf)
         , mVFS(vfs)
     {
         if (sProfilerEnabled)
-            lua_sethook(mLuaHolder.get(), &countHook, LUA_MASKCOUNT, countHookStep);
+            lua_sethook(mLuaState.get(), &countHook, LUA_MASKCOUNT, countHookStep);
 
         protectedCall([&](LuaView& view) {
             auto& sol = view.sol();

components/lua/luastate.hpp

@@ -10,6 +10,7 @@
 #include <components/vfs/pathutil.hpp>
 
 #include "configuration.hpp"
+#include "luastateptr.hpp"
 
 namespace VFS
 {
@@ -188,7 +189,7 @@ namespace LuaUtil
         static void countHook(lua_State* L, lua_Debug* ar);
         static void* trackingAllocator(void* ud, void* ptr, size_t osize, size_t nsize);
 
-        lua_State* createLuaRuntime(LuaState* luaState);
+        static LuaStatePtr createLuaRuntime(LuaState* luaState);
 
         struct AllocOwner
         {
@@ -206,25 +207,8 @@ namespace LuaUtil
         uint64_t mSmallAllocMemoryUsage = 0;
         std::vector<int64_t> mMemoryUsage;
 
-        class LuaStateHolder
-        {
-        public:
-            LuaStateHolder(lua_State* L)
-                : L(L)
-            {
-                sol::set_default_state(L);
-            }
-            ~LuaStateHolder() { lua_close(L); }
-            LuaStateHolder(const LuaStateHolder&) = delete;
-            LuaStateHolder(LuaStateHolder&&) = delete;
-            lua_State* get() { return L; }
-
-        private:
-            lua_State* L;
-        };
-
         // Must be declared before mSol and all sol-related objects. Then on exit it will be destructed the last.
-        LuaStateHolder mLuaHolder;
+        LuaStatePtr mLuaState;
 
         sol::state_view mSol;
         const ScriptsConfiguration* mConf;

components/lua/luastateptr.hpp

@@ -0,0 +1,18 @@
+#ifndef OPENMW_COMPONENTS_LUA_LUASTATEPTR_H
+#define OPENMW_COMPONENTS_LUA_LUASTATEPTR_H
+
+#include <sol/state.hpp>
+
+#include <memory>
+
+namespace LuaUtil
+{
+    struct CloseLuaState
+    {
+        void operator()(lua_State* state) noexcept { lua_close(state); }
+    };
+
+    using LuaStatePtr = std::unique_ptr<lua_State, CloseLuaState>;
+}
+
+#endif