Commit 8f1dd0c9 authored by Artur Grunau's avatar Artur Grunau
Browse files

Make Lua connections work with copyable signals

Until now, Lua connections had only stub implementations of several
sigslot's API methods, including clone() and getdest(). This led to
crashes when signals that contained Lua connections were copied.

Provide proper (if somewhat forced) implementations of clone() and
getdest() for Lua connections. This makes Lua connections work with
signals that may be copied.

References #1
parent 2e595fd0
......@@ -37,19 +37,33 @@ namespace sigslot {
class _lua_connection1 : public _connection_base1<arg1_type, mt_policy>
_lua_connection1() : _slot_fn() {}
_lua_connection1(SWIGLUA_REF slot_fn) : _slot_fn(slot_fn) {}
_lua_connection1() : _slot_fn(), _dummy_dest(nullptr) {}
_lua_connection1(SWIGLUA_REF slot_fn) : _slot_fn(slot_fn), _dummy_dest(nullptr) {}
virtual ~_lua_connection1() {
if (_dummy_dest != nullptr)
delete _dummy_dest;
virtual _connection_base1<arg1_type, mt_policy>* clone() {
return nullptr;
SWIGLUA_REF slot_fn;
swiglua_ref_set(&slot_fn, _slot_fn.L, -1);
lua_pop(_slot_fn.L, 1);
return new _lua_connection1(slot_fn);
virtual _connection_base1<arg1_type, mt_policy>* duplicate(sigslot::has_slots<mt_policy>* pnewdest) {
return clone();
* Because Lua connections do not have any external destination objects that could be
* copied (which in turn would require duplicating the connections for the copy), this
* method should never be invoked.
return nullptr;
virtual void emitSignal(arg1_type a1) {
......@@ -78,11 +92,19 @@ namespace sigslot {
virtual has_slots<mt_policy>* getdest() const {
return nullptr;
* Because Lua connections do not have any destination objects, a dummy one has to be
* created here and returned to comply with sigslot's API.
if (_dummy_dest == nullptr)
_dummy_dest = new has_slots<mt_policy>();
return _dummy_dest;
SWIGLUA_REF _slot_fn;
SWIGLUA_REF _slot_fn; ///< Reference to a Lua function acting as a slot
mutable has_slots<mt_policy>* _dummy_dest; ///< Dummy destination object needed to support getdest()
Supports Markdown
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment