diff options
Diffstat (limited to 'indra/llcommon/lua_function.cpp')
| -rw-r--r-- | indra/llcommon/lua_function.cpp | 62 |
1 files changed, 62 insertions, 0 deletions
diff --git a/indra/llcommon/lua_function.cpp b/indra/llcommon/lua_function.cpp index be39a7d095..850dff1a33 100644 --- a/indra/llcommon/lua_function.cpp +++ b/indra/llcommon/lua_function.cpp @@ -496,6 +496,9 @@ namespace using LuaStateMap = std::unordered_map<lua_State*, LuaState*>; static LuaStateMap sLuaStateMap; +// replacement next(), pairs(), ipairs() that understand setdtor() proxy args +int lua_proxydrill(lua_State* L); + } // anonymous namespace LuaState::LuaState(script_finished_fn cb): @@ -513,6 +516,28 @@ LuaState::LuaState(script_finished_fn cb): lua_register(mState, "print", LuaFunction::get("print_info")); // We don't want to have to prefix require(). lua_register(mState, "require", LuaFunction::get("require")); + + // Replace certain key global functions so they understand our + // LL.setdtor() proxy objects. + // (We could also do this for selected library functions as well, + // e.g. the table, string, math libraries... let's see if needed.) + for (const auto& func : { "next", "pairs", "ipairs" }) + { + // push the function's name string twice + lua_pushstring(mState, func); + lua_pushvalue(mState, -1); + // stack: name, name + // look up the existing global + lua_rawget(mState, LUA_GLOBALSINDEX); + // stack: name, global function + // bind original function as the upvalue for lua_proxydrill() + lua_pushcclosure(mState, lua_proxydrill, + stringize("lua_proxydrill(", func, ')').c_str(), + 1); + // stack: name, lua_proxydrill(func) + // global name = lua_proxydrill(func) + lua_rawset(mState, LUA_GLOBALSINDEX); + } } LuaState::~LuaState() @@ -1165,6 +1190,14 @@ void setdtor_refs::push_metatable(lua_State* L) -- don't fret about arg._target's __tostring metamethod, -- if any, because built-in tostring() deals with that return tostring(arg._target) + end, + __iter = function(arg) + local iter = (getmetatable(arg._target) or {}).__iter + if iter then + return iter(arg._target) + else + return next, arg._target + end end } )-", @@ -1172,6 +1205,7 @@ void setdtor_refs::push_metatable(lua_State* L) binop("sub", "-"), binop("mul", "*"), binop("div", "/"), + binop("idiv", "//"), binop("mod", "%"), binop("pow", "^"), binop("concat", ".."), @@ -1254,6 +1288,34 @@ int setdtor_refs::meta__index(lua_State* L) return 1; } +// replacement for global next(), pairs(), ipairs(): +// its lua_upvalueindex(1) is the original function it's replacing +int lua_proxydrill(lua_State* L) +{ + // Accept however many arguments the original function normally accepts. + // If our first arg is a userdata, check if it's a setdtor_refs proxy. + // Drill through as many levels of proxy wrapper as needed. + while (const setdtor_refs* ptr = lua_toclass<setdtor_refs>(L, 1)) + { + // push original object + lua_getref(L, ptr->objref); + // replace first argument with that + lua_replace(L, 1); + } + // We've reached a first argument that's not a setdtor() proxy. + // How many arguments were we passed, anyway? + int args = lua_gettop(L); + // Push the original function, captured as our upvalue. + lua_pushvalue(L, lua_upvalueindex(1)); + // Shift the stack so the original function is first. + lua_insert(L, 1); + // Call the original function with all original args, no error checking. + // Don't truncate however many values that function returns. + lua_call(L, args, LUA_MULTRET); + // Return as many values as the original function returned. + return lua_gettop(L); +} + // When Lua destroys a setdtor_refs userdata object, either from garbage // collection or from LL.atexit(lua_destroybounduserdata), it's time to keep // its promise to call the specified Lua destructor function with the |