Tuesdays idea of adding some code into the SyncSPVAction didn't feel
right.
A second look made clear that bloom filter updates make much more sense
to go hand in hand with sending a mempool message. Especially since they
depend on each other on the server side.
To-rehash:
the wallet may decide at any time that a new bloom filter is needed. It
then uses the superclass (code in p2plib) PrivacySegment, to build that
filter. As part of that we get a lock object which, when going out of
scope, makes the peers that are subscribed to the privacySegment send
out the filter.
This separation of concerns means that the subclass wallet in the app
doens't know about peers or messages, only its superclass PrivacySegment
does.
What we did in this change is make the PrivacySegment class decide to
combine a bloom update with a mempool call. Typicall only once per
connection.
This means I can remove hacks in the SyncSPVAction which forced the
sending of the mempool message separately.
We connect to the "first" priority stated segments first, in order to
allow the UX to be made much better since it may take a bit of time to
find peers.
The uint256 and CKeyID classes are the same baseclass with template
differences only, which makes them fragile to use for overloading.
As such rename the convenience overload slightly.
this adds a listener interface and a way to emit the callbacks on
changing of the filter.
This also adds a mutex since we expect the Peer to use the filter which
will likely live in its own thread.
This makes the class thread safe and re-entrant.
Notice that we use a recursive mutex to allow various usecase on
altering the bloom filter.
The most involved one is a complete replacement which calls clear and
then various calls to add() style methods.
Second is a single 'add' which can be done without the clear first.
The second needs an explicit lock in the add() methods, which would
deadlock in the first usecase if I didn't pick the recursive mutex.
Instead of forwarding one transaction at a time as the peer sends them
to us, bundle them in a group of transactions known to be merkle-checked
and all belonging together in one block.
Since the peer has no obligation (and with CTOR even less) to send the
transactions in natural order, we should get them per block so we know
all transactions forwarded have parents.
We reuse the NetworkManager lower level code in order to connect
to the Bitcoin P2P network.
This implements the basics for anyone wanting to be a player on
this network.
tomFlowee
TomZ