525e9dcba0 Add submitSolution to BlockTemplate interface (Sjors Provoost)
47b4875ef0 Add getCoinbaseMerklePath() to Mining interface (Sjors Provoost)
63d6ad7c89 Move BlockMerkleBranch back to merkle.{h,cpp} (Sjors Provoost)
Pull request description:
The new `BlockTemplate` interface introduced in #30440 allows for a more efficient way for a miner to submit the block solution. Instead of having the send the full block, it only needs to provide the nonce, timestamp, version fields and coinbase transaction.
This PR introduces `submitSolution()` for that. It's currently unused.
#29432 and https://github.com/Sjors/bitcoin/pull/48 use it to process the Stratum v2 message [SubmitSolution](https://github.com/stratum-mining/sv2-spec/blob/main/07-Template-Distribution-Protocol.md#77-submitsolution-client---server). The method should be sufficiently generic to work with alternative mining protocols (none exist that I'm aware off).
This PR also introduces `getCoinbaseMerklePath()`, which is needed in Stratum v2 to construct the `merkle_path` field of the `NewTemplate` message (see [spec](https://github.com/stratum-mining/sv2-spec/blob/main/07-Template-Distribution-Protocol.md#72-newtemplate-server---client)). The coinbase merkle path is also used in Stratum "v1", see e.g. https://bitcoin.stackexchange.com/questions/109820/questions-on-merkle-root-hashing-for-stratum-pools
This last function uses `BlockMerkleBranch` which was moved to the test code in #13191. The reason back then for moving it was that it was no longer used. This PR moves it back.
This PR does not change behaviour since both methods are unused.
ACKs for top commit:
achow101:
ACK 525e9dcba0
itornaza:
Code review ACK 525e9dcba0
tdb3:
Code review and light test ACK 525e9dcba0
ryanofsky:
Code review ACK 525e9dcba0. Left minor suggestions but none are important, and looks like this could be merged as-is
Tree-SHA512: 2a6a8f5d409ff4926643193cb67702240c7c687615414371e53383d2c13c485807f65e21e8ed98515b5456eca3d9fca13cec04675814a4081467d88b849c5653
It should be obvious that a wait is not needed if the tip does not
match.
Also, remove a comment that the blockTip notification was only meant for
the "UI". (It is used by other stuff for a long time)
An external program that uses the Mining interface may need quick access to some information in the block template, while it can wait a bit longer for the full raw transaction data.
This would be the case for a Stratum v2 Template Provider which needs to send a NewTemplate message (which doesn't include transactions) as quickly as possible.
Rather than pass options individually to createNewBlock and then
combining them into BlockAssembler::Options, this commit introduces
BlockCreateOptions and passes that instead.
Currently there's only one option (use_mempool) but the next
commit adds more.
Co-authored-by: Ryan Ofsky <ryan@ofsky.org>
The goal of interfaces is to eventually run in their own process,
so we can't use EXCLUSIVE_LOCKS_REQUIRED in their declaration.
However TestBlockValidaty will crash (in its call to ConnectBlock)
if the tip changes from under the proposed block.
Have the testBlockValidity implementation hold the lock instead,
and non-fatally check for this condition.
Set tip at the start of the function and only update it for a long poll.
Additionally have getTipHash return an optional, so the
caller can explicitly check that a tip exists.
