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			477 lines
		
	
	
	
		
			18 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
			
		
		
	
	
			477 lines
		
	
	
	
		
			18 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
#include "luastate.hpp"
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#ifndef NO_LUAJIT
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#include <luajit.h>
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#endif // NO_LUAJIT
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#include <filesystem>
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#include <fstream>
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#include <components/debug/debuglog.hpp>
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#include <components/files/conversion.hpp>
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#include <components/vfs/manager.hpp>
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#include "luastateptr.hpp"
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#include "scriptscontainer.hpp"
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#include "utf8.hpp"
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namespace LuaUtil
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{
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    static VFS::Path::Normalized packageNameToVfsPath(std::string_view packageName, const VFS::Manager& vfs)
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    {
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        std::string pathValue(packageName);
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        std::replace(pathValue.begin(), pathValue.end(), '.', '/');
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        VFS::Path::Normalized pathWithInit(pathValue + "/init.lua");
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        pathValue.append(".lua");
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        VFS::Path::Normalized path(pathValue);
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        if (vfs.exists(path))
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            return path;
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        else if (vfs.exists(pathWithInit))
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            return pathWithInit;
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        else
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            throw std::runtime_error("module not found: " + std::string(packageName));
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    }
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    static std::filesystem::path packageNameToPath(
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        std::string_view packageName, const std::vector<std::filesystem::path>& searchDirs)
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    {
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        std::string path(packageName);
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        std::replace(path.begin(), path.end(), '.', '/');
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        std::string pathWithInit = path + "/init.lua";
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        path.append(".lua");
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        for (const auto& base : searchDirs)
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        {
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            std::filesystem::path p1 = base / path;
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            if (std::filesystem::exists(p1))
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                return p1;
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            std::filesystem::path p2 = base / pathWithInit;
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            if (std::filesystem::exists(p2))
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                return p2;
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        }
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        throw std::runtime_error("module not found: " + std::string(packageName));
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    }
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    static const std::string safeFunctions[] = { "assert", "error", "ipairs", "next", "pairs", "pcall", "select",
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        "tonumber", "tostring", "type", "unpack", "xpcall", "rawequal", "rawget", "rawset", "setmetatable" };
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    static const std::string safePackages[] = { "coroutine", "math", "string", "table", "utf8" };
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    static constexpr int64_t countHookStep = 1000;
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    bool LuaState::sProfilerEnabled = true;
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    void LuaState::countHook(lua_State* L, lua_Debug* ar)
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    {
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        LuaState* self;
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        (void)lua_getallocf(L, reinterpret_cast<void**>(&self));
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        if (self->mActiveScriptIdStack.empty())
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            return;
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        const ScriptId& activeScript = self->mActiveScriptIdStack.back();
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        activeScript.mContainer->addInstructionCount(activeScript.mIndex, countHookStep);
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        self->mWatchdogInstructionCounter += countHookStep;
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        if (self->mSettings.mInstructionLimit > 0
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            && self->mWatchdogInstructionCounter > self->mSettings.mInstructionLimit)
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        {
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            lua_pushstring(L,
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                "Lua instruction count exceeded, probably an infinite loop in a script. "
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                "To change the limit set \"[Lua] instruction limit per call\" in settings.cfg");
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            lua_error(L);
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        }
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    }
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    void* LuaState::trackingAllocator(void* ud, void* ptr, size_t osize, size_t nsize)
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    {
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        LuaState* self = static_cast<LuaState*>(ud);
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        const uint64_t smallAllocSize = self->mSettings.mSmallAllocMaxSize;
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        const uint64_t memoryLimit = self->mSettings.mMemoryLimit;
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        if (!ptr)
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            osize = 0;
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        int64_t smallAllocDelta = 0, bigAllocDelta = 0;
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        if (osize <= smallAllocSize)
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            smallAllocDelta -= osize;
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        else
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            bigAllocDelta -= osize;
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        if (nsize <= smallAllocSize)
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            smallAllocDelta += nsize;
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        else
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            bigAllocDelta += nsize;
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        if (bigAllocDelta > 0 && memoryLimit > 0 && self->mTotalMemoryUsage + nsize - osize > memoryLimit)
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        {
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            Log(Debug::Error) << "Lua realloc " << osize << "->" << nsize
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                              << " is blocked because Lua memory limit (configurable in settings.cfg) is exceeded";
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            return nullptr;
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        }
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        void* newPtr = nullptr;
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        if (nsize == 0)
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            free(ptr);
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        else
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        {
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            newPtr = realloc(ptr, nsize);
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            if (!newPtr)
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            {
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                Log(Debug::Error) << "Lua realloc " << osize << "->" << nsize << " failed";
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                return nullptr;
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            }
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        }
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        self->mTotalMemoryUsage += smallAllocDelta + bigAllocDelta;
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        self->mSmallAllocMemoryUsage += smallAllocDelta;
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        if (bigAllocDelta != 0)
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        {
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            auto it = osize > smallAllocSize ? self->mBigAllocOwners.find(ptr) : self->mBigAllocOwners.end();
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            ScriptId id;
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            if (it != self->mBigAllocOwners.end())
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            {
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                if (it->second.mContainer)
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                    id = ScriptId{ *it->second.mContainer, it->second.mScriptIndex };
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                if (ptr != newPtr || nsize <= smallAllocSize)
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                    self->mBigAllocOwners.erase(it);
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            }
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            else if (bigAllocDelta > 0)
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            {
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                if (!self->mActiveScriptIdStack.empty())
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                    id = self->mActiveScriptIdStack.back();
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                bigAllocDelta = nsize;
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            }
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            if (id.mIndex >= 0)
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            {
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                if (static_cast<size_t>(id.mIndex) >= self->mMemoryUsage.size())
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                    self->mMemoryUsage.resize(id.mIndex + 1);
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                self->mMemoryUsage[id.mIndex] += bigAllocDelta;
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            }
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            if (id.mContainer)
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            {
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                id.mContainer->addMemoryUsage(id.mIndex, bigAllocDelta);
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                if (newPtr && nsize > smallAllocSize)
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                    self->mBigAllocOwners.emplace(newPtr, AllocOwner{ id.mContainer->mThis, id.mIndex });
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            }
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        }
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        return newPtr;
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    }
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    LuaStatePtr LuaState::createLuaRuntime(LuaState* luaState)
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    {
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        if (sProfilerEnabled)
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        {
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            Log(Debug::Info) << "Initializing LuaUtil::LuaState with profiler";
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            LuaStatePtr state(lua_newstate(&trackingAllocator, luaState));
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            if (state != nullptr)
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                return state;
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            sProfilerEnabled = false;
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            Log(Debug::Error) << "Failed to initialize LuaUtil::LuaState with custom allocator; disabling Lua profiler";
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        }
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        Log(Debug::Info) << "Initializing LuaUtil::LuaState without profiler";
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        LuaStatePtr state(luaL_newstate());
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        if (state == nullptr)
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            throw std::runtime_error("Failed to create Lua runtime");
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        return state;
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    }
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    LuaState::LuaState(const VFS::Manager* vfs, const ScriptsConfiguration* conf, const LuaStateSettings& settings)
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        : mSettings(settings)
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        , mLuaState([&] {
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            LuaStatePtr state = createLuaRuntime(this);
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            sol::set_default_state(state.get());
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            return state;
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        }())
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        , mSol(mLuaState.get())
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        , mConf(conf)
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        , mVFS(vfs)
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    {
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        if (sProfilerEnabled)
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            lua_sethook(mLuaState.get(), &countHook, LUA_MASKCOUNT, countHookStep);
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        protectedCall([&](LuaView& view) {
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            auto& sol = view.sol();
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            sol.open_libraries(sol::lib::base, sol::lib::coroutine, sol::lib::math, sol::lib::bit32, sol::lib::string,
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                sol::lib::table, sol::lib::os, sol::lib::debug);
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#ifndef NO_LUAJIT
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            sol.open_libraries(sol::lib::jit);
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#endif // NO_LUAJIT
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            sol["math"]["randomseed"](static_cast<unsigned>(std::time(nullptr)));
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            sol["math"]["randomseed"] = [] {};
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            sol["utf8"] = LuaUtf8::initUtf8Package(sol);
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            sol["writeToLog"] = [](std::string_view s) { Log(Debug::Level::Info) << s; };
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            sol["setEnvironment"]
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                = [](const sol::environment& env, const sol::function& fn) { sol::set_environment(env, fn); };
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            sol["loadFromVFS"] = [this](std::string_view packageName) {
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                return loadScriptAndCache(packageNameToVfsPath(packageName, *mVFS));
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            };
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            sol["loadInternalLib"] = [this](std::string_view packageName) { return loadInternalLib(packageName); };
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            // Some fixes for compatibility between different Lua versions
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            if (sol["unpack"] == sol::nil)
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                sol["unpack"] = sol["table"]["unpack"];
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            else if (sol["table"]["unpack"] == sol::nil)
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                sol["table"]["unpack"] = sol["unpack"];
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            if (LUA_VERSION_NUM <= 501)
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            {
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                sol.script(R"(
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                    local _pairs = pairs
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                    local _ipairs = ipairs
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                    pairs = function(v) return (rawget(getmetatable(v) or {}, '__pairs') or _pairs)(v) end
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                    ipairs = function(v) return (rawget(getmetatable(v) or {}, '__ipairs') or _ipairs)(v) end
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                )");
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            }
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            sol.script(R"(
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                local printToLog = function(...)
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                    local strs = {}
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                    for i = 1, select('#', ...) do
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                        strs[i] = tostring(select(i, ...))
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                    end
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                    return writeToLog(table.concat(strs, '\t'))
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                end
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                printGen = function(name) return function(...) return printToLog(name, ...) end end
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                function requireGen(env, loaded, loadFn)
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                    return function(packageName)
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                        local p = loaded[packageName]
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                        if p == nil then
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                            local loader = loadFn(packageName)
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                            setEnvironment(env, loader)
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                            p = loader(packageName)
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                            loaded[packageName] = p
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                        end
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                        return p
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                    end
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                end
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                function createStrictIndexFn(tbl)
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                    return function(_, key)
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                        local res = tbl[key]
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                        if res ~= nil then
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                            return res
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                        else
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                            error('Key not found: '..tostring(key), 2)
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                        end
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                    end
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                end
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                function pairsForReadOnly(v)
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                    local nextFn, t, firstKey = pairs(getmetatable(v).t)
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                    return function(_, k) return nextFn(t, k) end, v, firstKey
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                end
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                function ipairsForReadOnly(v)
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                    local nextFn, t, firstKey = ipairs(getmetatable(v).t)
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                    return function(_, k) return nextFn(t, k) end, v, firstKey
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                end
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                function lenForReadOnly(v)
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                    return #getmetatable(v).t
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                end
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                local function nextForArray(array, index)
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                    index = (index or 0) + 1
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                    if index <= #array then
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                        return index, array[index]
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                    end
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                end
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                function ipairsForArray(array)
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                    return nextForArray, array, 0
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                end
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                getmetatable('').__metatable = false
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                getSafeMetatable = function(v)
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                    if type(v) ~= 'table' then error('getmetatable is allowed only for tables', 2) end
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                    return getmetatable(v)
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                end
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            )");
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            mSandboxEnv = sol::table(sol, sol::create);
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            mSandboxEnv["_VERSION"] = sol["_VERSION"];
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            for (const std::string& s : safeFunctions)
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            {
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                if (sol[s] == sol::nil)
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                    throw std::logic_error("Lua function not found: " + s);
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                mSandboxEnv[s] = sol[s];
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            }
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            for (const std::string& s : safePackages)
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            {
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                if (sol[s] == sol::nil)
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                    throw std::logic_error("Lua package not found: " + s);
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                mCommonPackages[s] = mSandboxEnv[s] = makeReadOnly(sol[s]);
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            }
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            mSandboxEnv["getmetatable"] = sol["getSafeMetatable"];
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            mCommonPackages["os"] = mSandboxEnv["os"]
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                = makeReadOnly(tableFromPairs<std::string_view, sol::function>(sol,
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                    { { "date", sol["os"]["date"] }, { "difftime", sol["os"]["difftime"] },
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                        { "time", sol["os"]["time"] } }));
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        });
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    }
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    sol::table makeReadOnly(const sol::table& table, bool strictIndex)
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    {
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        if (table == sol::nil)
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            return table;
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        if (table.is<sol::userdata>())
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            return table; // it is already userdata, no sense to wrap it again
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        lua_State* luaState = table.lua_state();
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        sol::state_view lua(luaState);
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        sol::table meta(lua, sol::create);
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        meta["t"] = table;
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        if (strictIndex)
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            meta[sol::meta_method::index] = lua["createStrictIndexFn"](table);
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        else
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            meta[sol::meta_method::index] = table;
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        meta[sol::meta_method::pairs] = lua["pairsForReadOnly"];
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        meta[sol::meta_method::ipairs] = lua["ipairsForReadOnly"];
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        meta[sol::meta_method::length] = lua["lenForReadOnly"];
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        meta[sol::meta_method::type] = "ReadOnlyTable";
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        lua_newuserdata(luaState, 0);
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        sol::stack::push(luaState, meta);
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        lua_setmetatable(luaState, -2);
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        return sol::stack::pop<sol::table>(luaState);
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    }
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    sol::table getMutableFromReadOnly(const sol::userdata& ro)
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    {
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        return ro[sol::metatable_key].get<sol::table>()["t"];
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    }
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    void LuaState::addCommonPackage(std::string packageName, sol::object package)
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    {
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        if (!package.is<sol::function>())
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            package = makeReadOnly(std::move(package));
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        mCommonPackages.insert_or_assign(std::move(packageName), std::move(package));
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    }
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    sol::protected_function_result LuaState::runInNewSandbox(const VFS::Path::Normalized& path,
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        const std::string& envName, const std::map<std::string, sol::main_object>& packages,
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        const sol::main_object& hiddenData)
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    {
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        // TODO
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        sol::protected_function script = loadScriptAndCache(path);
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        sol::environment env(mSol, sol::create, mSandboxEnv);
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        env["print"] = mSol["printGen"](envName + ":");
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        env["_G"] = env;
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        env[sol::metatable_key]["__metatable"] = false;
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        ScriptId scriptId;
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        if (hiddenData.is<sol::table>())
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            scriptId = hiddenData.as<sol::table>()
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                           .get<sol::optional<ScriptId>>(ScriptsContainer::sScriptIdKey)
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                           .value_or(ScriptId{});
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        auto maybeRunLoader = [&hiddenData, scriptId](const sol::object& package) -> sol::object {
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            if (package.is<sol::function>())
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                return call(scriptId, package.as<sol::function>(), hiddenData);
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            else
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                return package;
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        };
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        sol::table loaded(mSol, sol::create);
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        for (const auto& [key, value] : mCommonPackages)
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            loaded[key] = maybeRunLoader(value);
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        for (const auto& [key, value] : packages)
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            loaded[key] = maybeRunLoader(value);
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        env["require"] = mSol["requireGen"](env, loaded, mSol["loadFromVFS"]);
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        sol::set_environment(env, script);
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        return call(scriptId, script);
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    }
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    sol::environment LuaState::newInternalLibEnvironment()
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    {
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        // TODO
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        sol::environment env(mSol, sol::create, mSandboxEnv);
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        sol::table loaded(mSol, sol::create);
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        for (const std::string& s : safePackages)
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            loaded[s] = static_cast<sol::object>(mSandboxEnv[s]);
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        env["require"] = mSol["requireGen"](env, loaded, mSol["loadInternalLib"]);
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        return env;
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    }
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    sol::protected_function_result LuaState::throwIfError(sol::protected_function_result&& res)
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    {
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        if (!res.valid())
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            throw std::runtime_error(std::string("Lua error: ") += res.get<sol::error>().what());
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        else
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            return std::move(res);
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    }
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    sol::function LuaState::loadScriptAndCache(const VFS::Path::Normalized& path)
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    {
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        auto iter = mCompiledScripts.find(path);
 | 
						|
        if (iter != mCompiledScripts.end())
 | 
						|
        {
 | 
						|
            sol::load_result res = mSol.load(iter->second.as_string_view(), path.value(), sol::load_mode::binary);
 | 
						|
            // Unless we have memory corruption issues, the bytecode is valid at this point, but loading might still
 | 
						|
            // fail because we've hit our Lua memory cap
 | 
						|
            if (!res.valid())
 | 
						|
                throw std::runtime_error("Lua error: " + res.get<std::string>());
 | 
						|
            return res;
 | 
						|
        }
 | 
						|
        sol::function res = loadFromVFS(path);
 | 
						|
        mCompiledScripts[path] = res.dump();
 | 
						|
        return res;
 | 
						|
    }
 | 
						|
 | 
						|
    sol::function LuaState::loadFromVFS(const VFS::Path::Normalized& path)
 | 
						|
    {
 | 
						|
        std::string fileContent(std::istreambuf_iterator<char>(*mVFS->get(path)), {});
 | 
						|
        sol::load_result res = mSol.load(fileContent, path.value(), sol::load_mode::text);
 | 
						|
        if (!res.valid())
 | 
						|
            throw std::runtime_error(std::string("Lua error: ") += res.get<sol::error>().what());
 | 
						|
        return res;
 | 
						|
    }
 | 
						|
 | 
						|
    sol::function LuaState::loadInternalLib(std::string_view libName)
 | 
						|
    {
 | 
						|
        const auto path = packageNameToPath(libName, mLibSearchPaths);
 | 
						|
        std::ifstream stream(path);
 | 
						|
        std::string fileContent(std::istreambuf_iterator<char>(stream), {});
 | 
						|
        sol::load_result res = mSol.load(fileContent, Files::pathToUnicodeString(path), sol::load_mode::text);
 | 
						|
        if (!res.valid())
 | 
						|
            throw std::runtime_error("Lua error: " + res.get<std::string>());
 | 
						|
        return res;
 | 
						|
    }
 | 
						|
 | 
						|
    std::string getLuaVersion()
 | 
						|
    {
 | 
						|
#ifdef NO_LUAJIT
 | 
						|
        return LUA_RELEASE;
 | 
						|
#else
 | 
						|
        return LUA_RELEASE " (" LUAJIT_VERSION ")";
 | 
						|
#endif
 | 
						|
    }
 | 
						|
 | 
						|
    std::string toString(const sol::object& obj)
 | 
						|
    {
 | 
						|
        if (obj == sol::nil)
 | 
						|
            return "nil";
 | 
						|
        else if (obj.get_type() == sol::type::string)
 | 
						|
            return "\"" + obj.as<std::string>() + "\"";
 | 
						|
        else
 | 
						|
            return call(sol::state_view(obj.lua_state())["tostring"], obj);
 | 
						|
    }
 | 
						|
 | 
						|
    std::string Internal::formatCastingError(const sol::object& obj, const std::type_info& t)
 | 
						|
    {
 | 
						|
        const char* typeName = t.name();
 | 
						|
        if (t == typeid(int))
 | 
						|
            typeName = "int";
 | 
						|
        else if (t == typeid(unsigned))
 | 
						|
            typeName = "uint32";
 | 
						|
        else if (t == typeid(size_t))
 | 
						|
            typeName = "size_t";
 | 
						|
        else if (t == typeid(float))
 | 
						|
            typeName = "float";
 | 
						|
        else if (t == typeid(double))
 | 
						|
            typeName = "double";
 | 
						|
        else if (t == typeid(sol::table))
 | 
						|
            typeName = "sol::table";
 | 
						|
        else if (t == typeid(sol::function) || t == typeid(sol::protected_function))
 | 
						|
            typeName = "sol::function";
 | 
						|
        else if (t == typeid(std::string) || t == typeid(std::string_view))
 | 
						|
            typeName = "string";
 | 
						|
        return std::string("Value \"") + toString(obj) + std::string("\" can not be casted to ") + typeName;
 | 
						|
    }
 | 
						|
}
 |