diff options
Diffstat (limited to 'indra')
| -rw-r--r-- | indra/llcommon/lua_function.cpp | 67 |
1 files changed, 30 insertions, 37 deletions
diff --git a/indra/llcommon/lua_function.cpp b/indra/llcommon/lua_function.cpp index 3e3934c9c1..7894c7b96a 100644 --- a/indra/llcommon/lua_function.cpp +++ b/indra/llcommon/lua_function.cpp @@ -496,17 +496,24 @@ LuaState::~LuaState() // implicitly garbage-collect everything, so (for instance) any lingering // objects with __gc metadata methods aren't cleaned up. This is why we // provide atexit(). - luaL_checkstack(mState, 3, nullptr); - // look up Registry["atexit"] + luaL_checkstack(mState, 2, nullptr); + // look up Registry.atexit lua_getfield(mState, LUA_REGISTRYINDEX, "atexit"); - // stack contains Registry["atexit"] + // stack contains Registry.atexit if (lua_istable(mState, -1)) { - lua_pushnil(mState); // first key - while (lua_next(mState, -2)) + // We happen to know that Registry.atexit is built by appending array + // entries using table.insert(). That's important because it means + // there are no holes, and therefore lua_objlen() should be correct. + // That's important because we walk the atexit table backwards, to + // destroy last the things we created (passed to LL.atexit()) first. + for (int i(lua_objlen(mState, -1)); i >= 1; --i) { - // stack contains Registry["atexit"], key, value - // Call value(), no args, no return values. + lua_pushinteger(mState, i); + // stack contains Registry.atexit, i + lua_gettable(mState, -2); + // stack contains Registry.atexit, atexit[i] + // Call atexit[i](), no args, no return values. // Use lua_pcall() because errors in any one atexit() function // shouldn't cancel the rest of them. if (lua_pcall(mState, 0, 0, 0) != LUA_OK) @@ -516,11 +523,10 @@ LuaState::~LuaState() // pop error message lua_pop(mState, 1); } - // Normally we would pop value, keeping the key for the next - // iteration. But lua_pcall() has already popped the value. + // lua_pcall() has already popped atexit[i]: stack contains atexit } } - // pop Registry["atexit"] (either table or nil) + // pop Registry.atexit (either table or nil) lua_pop(mState, 1); lua_close(mState); @@ -710,37 +716,24 @@ lua_function(atexit, "register a Lua function to be called at script termination luaL_checkstack(L, 4, nullptr); // look up the global name "table" lua_getglobal(L, "table"); - // stack contains function, "table" + // stack contains function, table // look up table.insert lua_getfield(L, -1, "insert"); - // stack contains function, "table", "insert" - // look up the "atexit" table in the Registry - lua_getfield(L, LUA_REGISTRYINDEX, "atexit"); - // stack contains function, "table", "insert", Registry["atexit"] - if (! lua_istable(L, -1)) - { - llassert(lua_isnil(L, -1)); - // stack contains function, "table", "insert", nil - lua_pop(L, 1); - // make a new, empty table - lua_newtable(L); - // stack contains function, "table", "insert", {} - // duplicate the table reference on the stack - lua_pushvalue(L, -1); - // stack contains function, "table", "insert", {}, {} - // store the new empty "atexit" table to the Registry, leaving a - // reference on the stack - lua_setfield(L, LUA_REGISTRYINDEX, "atexit"); - } - // stack contains function, "table", "insert", Registry["atexit"] - // we were called with a Lua function to append to that Registry["atexit"] - // table -- push that function - lua_pushvalue(L, 1); // or -4 - // stack contains function, "table", "insert", Registry["atexit"], function - // call table.insert(atexit, function) + // stack contains function, table, table.insert + // ditch table + lua_replace(L, -2); + // stack contains function, table.insert + // find or create the "atexit" table in the Registry + luaL_newmetatable(L, "atexit"); + // stack contains function, table.insert, Registry.atexit + // we were called with a Lua function to append to that Registry.atexit + // table -- push function + lua_pushvalue(L, 1); // or -3 + // stack contains function, table.insert, Registry.atexit, function + // call table.insert(Registry.atexit, function) // don't use pcall(): if there's an error, let it propagate lua_call(L, 2, 0); - // stack contains function, "table" -- pop everything + // stack contains function -- pop everything lua_settop(L, 0); return 0; } |