C回调lua引用，lua回调C函数

C代码：

#include "windows.h"
#include

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


#pragma   comment(lib,"lua5.1.lib")


lua_State * L;

static int foo (lua_State *L) {
    const char *buff = luaL_checkstring(L, -1);
    printf(buff);
    return 0;                   /* number of results */
}

static int clib(lua_State *L)   //给lua调用的c函数必须定义成static int XXX(lua_State *L)
{
    const char *buff = luaL_checkstring(L, -1);
    //从栈顶弹出一个值
    lua_pop(L, 1);
    //lua_pop(L, -1); //清栈

    //创建索引并从栈顶弹出该对象
    int ref = luaL_ref(L, LUA_REGISTRYINDEX);
    //根据索引取lua对象并压栈
    lua_rawgeti(L, LUA_REGISTRYINDEX, ref);
    if (!lua_isfunction(L, -1))
    {
        printf("call back function is not valid:%d", ref);
        return 0;
    }
    //压入参数
    lua_pushstring(L, buff);
    lua_pushcfunction(L, (lua_CFunction)foo);

    //运行
    lua_pcall(L, 2, 0,0);
    const char * err = luaL_checkstring(L, 1);
    printf("%d,err:%s/n", lua_gettop(L),  err);
    luaL_unref(L, LUA_REGISTRYINDEX, ref);
    return 0;   //为什么要返回1？这是有依据的，该函数把结果压入了栈，lua调用该函数将从栈中
    //取1个结果  */
}


static const luaL_reg lengine[] = {
    {"clib", clib},
    {NULL, NULL},
};


int main()
{
    //创建一个指向lua解释器的指针
    L = luaL_newstate();
    //加载lua标准库
    luaL_openlibs(L);
    //注册C++函数
    lua_register(L,"clib",clib);
    //加载脚本
    luaL_register(L, "lengine", lengine);
    luaL_dofile(L,"1.lua");
    //调用函数
    // lua_getglobal(L,"run");
    //运行函数并把结果压入栈
    // lua_pcall(L,0,0,0);
    //关闭并释放资源
    lua_close(L);
    return 0;
}

 

 

lua代码：

local b = {}
function b.a(str, cfunc)
    print("OK")
    print("lua" .. str)
     cfunc("this is c function/n")
end

lengine.clib(b.a, "test")