/* ---------------------------------------------------------------------------------------- */
protected void ListAdd(SignalConnectionBase conn, bool prioritize)
{
if (prioritize)
{
// Prepend it to the beginning of the list
conn._next = _head;
_head = conn;
}
else
{
// Append it to the end of the list
SignalConnectionBase tail = null, p = _head;
while (p != null)
{
tail = p;
p = p._next;
}
if (tail != null)
{
tail._next = conn;
}
else
{
_head = conn;
}
}
}
/* ---------------------------------------------------------------------------------------- */
protected void DidEmit(SignalConnectionBase head)
{
_head = head;
Task snapshot = _deferredTasks;
_deferredTasks = null;
while (snapshot != null)
{
snapshot.fn();
snapshot = snapshot.next;
}
}
/* ---------------------------------------------------------------------------------------- */
protected SignalConnectionBase WillEmit()
{
// Should never happen, since the public emit methods will defer, but just in case...
if (Dispatching())
{
throw new Exception();
}
SignalConnectionBase snapshot = _head;
_head = DISPATCHING_SENTINEL;
return(snapshot);
}
/* ---------------------------------------------------------------------------------------- */
public void Disconnect(SignalConnectionBase conn)
{
if (Dispatching())
{
Defer(delegate() {
ListRemove(conn);
});
}
else
{
ListRemove(conn);
}
}
/* ---------------------------------------------------------------------------------------- */
protected SignalConnection ConnectImpl(Action listener, bool prioritize)
{
SignalConnectionBase conn = new SignalConnectionBase(this, listener);
if (Dispatching())
{
Defer(delegate() {
ListAdd(conn, prioritize);
});
}
else
{
ListAdd(conn, prioritize);
}
return(conn);
}
/* ---------------------------------------------------------------------------------------- */
private void EmitImpl()
{
SignalConnectionBase head = WillEmit();
SignalConnectionBase p = head;
while (p != null)
{
p._listener();
if (!p.stayInList)
{
p.Dispose();
}
p = p._next;
}
DidEmit(head);
}
/* ---------------------------------------------------------------------------------------- */
protected void ListRemove(SignalConnectionBase conn)
{
SignalConnectionBase prev = null, p = _head;
while (p != null)
{
if (p == conn)
{
// Splice out p
var next = p._next;
if (prev == null)
{
_head = next;
}
else
{
prev._next = next;
}
return;
}
prev = p;
p = p._next;
}
}
/* ---------------------------------------------------------------------------------------- */
public Signal(Action listener = null)
{
_head = (listener != null) ? new SignalConnectionBase(this, listener) : null;
_deferredTasks = null;
}
