s_base.h

Go to the documentation of this file.

// Luanti
// SPDX-License-Identifier: LGPL-2.1-or-later
// Copyright (C) 2013 celeron55, Perttu Ahola <celeron55@gmail.com>
 
#pragma once
 
#include <iostream>
#include <string>
#include <thread>
#include <mutex>
#include <unordered_map>
#include "common/helper.h"
#include "util/basic_macros.h"
 
extern "C" {
#include <lua.h>
#include <lualib.h>
}
 
#include "irrlichttypes.h"
#include "common/c_types.h"
#include "common/c_internal.h"
#include "debug.h"
#include "config.h"
 
#define SCRIPTAPI_LOCK_DEBUG
 
// MUST be an invalid mod name so that mods can't
// use that name to bypass security!
#define BUILTIN_MOD_NAME "*builtin*"
 
#define PCALL_RES(RES) {                    \
        int result_ = (RES);                    \
        if (result_ != 0) {                     \
                scriptError(result_, __FUNCTION__); \
        }                                       \
}
 
#define runCallbacks(nargs, mode) \
        runCallbacksRaw((nargs), (mode), __FUNCTION__)
 
#define setOriginFromTable(index) \
        setOriginFromTableRaw(index, __FUNCTION__)
 
enum class ScriptingType: u8 {
        Async, // either mainmenu (client) or ingame (server)
        Client,
        MainMenu,
        Server,
        Emerge
};
 
class Server;
#if CHECK_CLIENT_BUILD()
class Client;
#endif
class EmergeThread;
class IGameDef;
class Environment;
class GUIEngine;
class ServerActiveObject;
struct PlayerHPChangeReason;
 
class ScriptApiBase : protected LuaHelper {
public:
        ScriptApiBase(ScriptingType type);
        // fake constructor to allow script API classes (e.g ScriptApiEnv) to virtually inherit from this one.
        ScriptApiBase()
        {
                FATAL_ERROR("ScriptApiBase created without ScriptingType!");
        }
        virtual ~ScriptApiBase();
        DISABLE_CLASS_COPY(ScriptApiBase);
 
        // These throw a ModError on failure
        void loadMod(const std::string &script_path, const std::string &mod_name);
        void loadScript(const std::string &script_path);
 
#if CHECK_CLIENT_BUILD()
        void loadModFromMemory(const std::string &mod_name);
#endif
 
        void runCallbacksRaw(int nargs,
                RunCallbacksMode mode, const char *fxn);
 
        /* object */
        void addObjectReference(ServerActiveObject *cobj);
        void removeObjectReference(ServerActiveObject *cobj);
 
        ScriptingType getType() { return m_type; }
 
        IGameDef *getGameDef() { return m_gamedef; }
        Server* getServer();
#if CHECK_CLIENT_BUILD()
        Client* getClient();
#endif
 
        // IMPORTANT: These cannot be used for any security-related uses, they exist
        // only to enrich error messages.
        const std::string &getOrigin() { return m_last_run_mod; }
        void setOriginDirect(const char *origin);
        void setOriginFromTableRaw(int index, const char *fxn);
 
        // Returns the currently running mod, only during init time.
        // The reason this is "insecure" is that mods can mess with each others code,
        // so the boundary of who is responsible is fuzzy.
        // Note: checking this against BUILTIN_MOD_NAME is always safe (not spoofable).
        // returns "" on error
        static std::string getCurrentModNameInsecure(lua_State *L);
        // Returns the currently running mod, only during init time.
        // This checks the Lua stack to only permit direct calls in the file
        // scope. That way it is assured that it's really the mod it claims to be.
        // returns "" on error
        static std::string getCurrentModName(lua_State *L);
 
#if !CHECK_CLIENT_BUILD()
        inline void clientOpenLibs(lua_State *L) { assert(false); }
#else
        void clientOpenLibs(lua_State *L);
#endif
 
        // Check things that should be set by the builtin mod.
        void checkSetByBuiltin();
 
protected:
        friend class LuaABM;
        friend class LuaLBM;
        friend class InvRef;
        friend class ObjectRef;
        friend class NodeMetaRef;
        friend class ModApiBase;
        friend class ModApiEnv;
        friend class LuaVoxelManip;
        friend class TestMoveAction; // needs getStack()
 
        /*
                Subtle edge case with coroutines: If for whatever reason you have a
                method in a subclass that's called from existing lua_CFunction
                (any of the l_*.cpp files) then make it static and take the lua_State*
                as an argument. This is REQUIRED because getStack() will not return the
                correct state if called inside coroutines.
 
                Also note that src/script/common/ is the better place for such helpers.
        */
        lua_State* getStack()
                { return m_luastack; }
 
        // Checks that stack size is sane
        void realityCheck();
        // Takes an error from lua_pcall and throws it as a LuaError
        void scriptError(int result, const char *fxn);
        // Dumps stack contents for debugging
        void stackDump(std::ostream &o);
 
        void setGameDef(IGameDef* gamedef) { m_gamedef = gamedef; }
 
        Environment* getEnv() { return m_environment; }
        void setEnv(Environment* env) { m_environment = env; }
 
#if CHECK_CLIENT_BUILD()
        GUIEngine* getGuiEngine() { return m_guiengine; }
        void setGuiEngine(GUIEngine* guiengine) { m_guiengine = guiengine; }
#endif
 
        EmergeThread* getEmergeThread() { return m_emerge; }
        void setEmergeThread(EmergeThread *emerge) { m_emerge = emerge; }
 
        void objectrefGetOrCreate(lua_State *L, ServerActiveObject *cobj);
 
        void pushPlayerHPChangeReason(lua_State *L, const PlayerHPChangeReason& reason);
 
        std::recursive_mutex m_luastackmutex;
        std::string     m_last_run_mod;
        bool            m_secure = false;
#ifdef SCRIPTAPI_LOCK_DEBUG
        int             m_lock_recursion_count{};
        std::thread::id m_owning_thread;
#endif
 
private:
        static int luaPanic(lua_State *L);
 
        lua_State      *m_luastack = nullptr;
 
        IGameDef       *m_gamedef = nullptr;
        Environment    *m_environment = nullptr;
#if CHECK_CLIENT_BUILD()
        GUIEngine      *m_guiengine = nullptr;
#endif
        EmergeThread   *m_emerge = nullptr;
 
        ScriptingType  m_type;
};