It's possible coins with the same hash exist when you create a duplicate coinbase, so previously we were reading from the database to make sure we had the old coins cached so if we were to spend the new ones, the old ones would also be spent. This pull instead just marks the new coins as not fresh if they are from a coinbase, so if they are spent they will be written all the way down to the database anyway overwriting any duplicates.
Previously it would break if you flushed a parent cache while there was a child cache referring to it. This change will allow the flushing of parent caches.
1cf3dd8 Add unit test for UpdateCoins (Alex Morcos)
03c8282 Make CCoinsViewTest behave like CCoinsViewDB (Alex Morcos)
14470f9 ModifyNewCoins saves database lookups (Alex Morcos)
bbf49da Fix comment for blocksonly parameter interactions (Patick Strateman)
6a4982f Fix fRelayTxs comment (Patick Strateman)
59441a0 Display DEFAULT_WHITELISTALWAYSRELAY in help text (Patick Strateman)
71a2683 Use DEFAULT_BLOCKSONLY and DEFAULT_WHITELISTALWAYSRELAY constants (Patick Strateman)
762b13b Add help text for blocksonly and whitelistalwaysrelay (Patick Strateman)
3a96497 Add whitelistalwaysrelay option (Patick Strateman)
420fa81 Do not process tx inv's in blocksonly mode (Patick Strateman)
4044f07 Add blocksonly mode (Patick Strateman)
10953a7 Better error message for fundrawtransaction w/ empty vout (Peter Todd)
61e1eb2 Actually use includeWatching value in fundrawtransaction (Peter Todd)
This continues/fixes #6719.
`event_base_loopbreak` was not doing what I expected it to, at least in
libevent 2.0.21.
What I expected was that it sets a timeout, given that no other pending
events it would exit in N seconds. However, what it does was delay the
event loop exit with 10 seconds, even if nothing is pending.
Solve it in a different way: give the event loop thread time to exit
out of itself, and if it doesn't, send loopbreak.
This speeds up the RPC tests a lot, each exit incurred a 10 second
overhead, with this change there should be no shutdown overhead in the
common case and up to two seconds if the event loop is blocking.
As a bonus this breaks dependency on boost::thread_group, as the HTTP
server minds its own offspring.
Alex Morcos