Method executeFunction

extensions/scripting/lua-bindings/manual/LuaStack.cpp:454–513

}

int LuaStack::executeFunction(int numArgs)
{
    int functionIndex = -(numArgs + 1);
    if (!lua_isfunction(_state, functionIndex))
    {
        AXLOGE("value at stack [{}] is not function", functionIndex);
        lua_pop(_state, numArgs + 1);  // remove function and arguments
        return 0;
    }

    int traceback = 0;
    lua_getglobal(_state, "__G__TRACKBACK__"); /* L: ... func arg1 arg2 ... G */
    if (!lua_isfunction(_state, -1))
    {
        lua_pop(_state, 1); /* L: ... func arg1 arg2 ... */
    }
    else
    {
        lua_insert(_state, functionIndex - 1); /* L: ... G func arg1 arg2 ... */
        traceback = functionIndex - 1;
    }

    int error = 0;
    ++_callFromLua;
    error = lua_pcall(_state, numArgs, 1, traceback); /* L: ... [G] ret */
    --_callFromLua;
    if (error)
    {
        if (traceback == 0)
        {
            AXLOGE("[LUA ERROR] {}", lua_tostring(_state, -1)); /* L: ... error */
            lua_pop(_state, 1);                                // remove error message from stack
        }
        else /* L: ... G error */
        {
            lua_pop(_state, 2);  // remove __G__TRACKBACK__ and error message from stack
        }
        return 0;
    }

    // get return value
    int ret = 0;
    if (lua_isnumber(_state, -1))
    {
        ret = (int)lua_tointeger(_state, -1);
    }
    else if (lua_isboolean(_state, -1))
    {
        ret = (int)lua_toboolean(_state, -1);
    }
    // remove return value from stack
    lua_pop(_state, 1); /* L: ... [G] */

    if (traceback)
    {
        lua_pop(_state, 1);  // remove __G__TRACKBACK__ from stack      /* L: ... */
    }