axmol/cocos/scripting/lua-bindings/manual/CCLuaBridge.h

/****************************************************************************
 Copyright (c) 2013-2016 Chukong Technologies Inc.
 Copyright (c) 2017-2018 Xiamen Yaji Software Co., Ltd.
 
 http://www.cocos2d-x.org
 
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 The above copyright notice and this permission notice shall be included in
 all copies or substantial portions of the Software.
 
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#ifndef __LUA_BRIDGE_H_
#define __LUA_BRIDGE_H_

#include <string>
#include <map>
#include "scripting/lua-bindings/manual/CCLuaEngine.h"

extern "C" {
#include "lua.h"
}

using namespace std;
/**
 * @addtogroup lua
 * @{
 */

NS_CC_BEGIN
/** LuaBridge Error enum, with inline docs. */
typedef enum {
    kLuaBridgeErrorOk                   = 0,  /** &lt; value 0 */
    kLuaBridgeErrorInvalidParameters    = -1, /** &lt; value -1 */
    kLuaBridgeErrorClassNotFound        = -2, /** &lt; value -2 */
    kLuaBridgeErrorMethodNotFound       = -3, /** &lt; value -3 */
    kLuaBridgeErrorExceptionOccurred    = -4, /** &lt; value -4 */
    kLuaBridgeErrorMethodSignature      = -5, /** &lt; value -5 */
    kLuaBridgeErrorJavaVMError          = -6, /** &lt; value -6 */
} LuaBridgeError;

#define LUA_BRIDGE_REGISTRY_FUNCTION    "lua_bridge_function_id"        // table[function] = id
#define LUA_BRIDGE_REGISTRY_RETAIN      "lua_bridge_function_id_retain" // table[id] = retain count

/**
 * Build bridge between ObjC and Lua.
 * It makes Lua and ObjC can call each other conveniently.
 *
 * @lua NA
 * @js NA
 */
class LuaBridge
{
public:
    /**
     * Get the LuaStack of LuaEngine.
     *
     * @return the LuaStack object.
     */
    static LuaStack *getStack();
    /**
     * Push the function pointer corresponding to functionId on the top of lua stack by searching the `lua_bridge_function_id` table.
     * If it don't find the function pointer corresponding to functionId, it will reset stack top index to the index before searching.
     *
     * @param functionId the value used to search the `lua_bridge_function_id` table.
     */
    static int pushLuaFunctionById(int functionId);
    
    /**
     * The retain count would be increase by 1 corresponding to functionId in the `lua_bridge_function_id_retain` table if it could be found.
     * If `lua_bridge_function_id_retain` table is not existed or the type of lua_bridge_function_id_retain[functionId] isn't LUA_TNUMBER, It would return 0.
     * The top index of lua stack the same as before calling this function.
     *
     * @param functionId the value used to search the `lua_bridge_function_id_retain` table.
     * @return the retain count or 0.
     */
    static int retainLuaFunctionById(int functionId);
    
    /**
     *
     * The retain count would be reduced by 1 corresponding to functionId in the `lua_bridge_function_id_retain` table if it could be found.
     * If `lua_bridge_function_id` table or `lua_bridge_function_id_retain` aren't found, it would return 0.
     * If the value of retain count is 0 after reducing, it would update the `lua_bridge_function_id_retain` table and `lua_bridge_function_id_retain` table to remove the  reference corresponding to this functionId
     *
     * @param functionId the value used to search the `lua_bridge_function_id` table and `lua_bridge_function_id` table.
     * @return the retain count or 0.
     */
    static int releaseLuaFunctionById(int functionId);
    
protected:
    static int retainLuaFunction(lua_State *L, int functionIndex, int *retainCountReturn);

    static lua_State *s_luaState;
    static int        s_newFunctionId;
};

NS_CC_END

// end group
/// @}

#endif // __LUA_BRIDGE_H_