Implement the bucketing by source group and group using essentially the
same algorithm as the address maanger in bitcoind.
Fix up the saving of peer.json to do so in a json format that keeps bucket
metadata.
If we fail to load the some of the data we asssume that we have
incomplete information, so we nuke the existing file and reinitialise so
we have a clean slate.
- Remove leftover debug log prints
- Increment waitgroup outside of goroutine
- Various comment and log message consistency
- Combine peer setup and newPeer -> newInboundPeer
- Save and load peers.json to/from cfg.DataDir
- Only claim addrmgr needs more addresses when it has less than 1000
- Add warning if unkown peer on orphan block.
Use it to add multiple peer support. We try and keep 8 outbound peers
active at all times.
This address manager is not as complete as the one in bitcoind yet, but
additional functionality is being worked on.
We currently handle (in a similar manner to bitcoind):
- biasing between new and already tried addresses based on number of connected
peers.
- rejection of non-default ports until desparate
- address selection probabilities based on last successful connection and number
of failures.
- routability checks based on known unroutable subnets.
- only connecting to each network `group' once at any one time.
We currently lack support for:
- tor ``addresses'' (an .onion address encoded in 64 bytes of ip address)
- full state save and restore (we just save a json with the list of known
addresses in it)
- multiple buckets for new and tried addresses selected by a hash of address and
source. The current algorithm functions the same as bitcoind would with only
one bucket for new and tried (making the address cache rather smaller than it
otherwise would be).
This commit changes the code so that all calls to .Add on waitgroups
happen before the associated goroutines are launched. Doing this after
the goroutine could technically cause a race where the goroutine started
and finished before the main goroutine has a chance to increment the
counter. In our particular case none of the goroutines exit quickly
enough for this to be an issue, but nevertheless the correct way should be
used.
