05117e6e17 rpc: clarify longpoll behavior (Sjors Provoost)
5315278e7c Have createNewBlock() wait for a tip (Sjors Provoost)
64a2795fd4 rpc: handle shutdown during long poll and wait methods (Sjors Provoost)
a3bf43343f rpc: drop unneeded IsRPCRunning() guards (Sjors Provoost)
f9cf8bd0ab Handle negative timeout for waitTipChanged() (Sjors Provoost)
Pull request description:
This PR prevents Mining interface methods from sometimes crashing when called during startup before a tip is connected. It also makes other improvements like making more RPC methods usable from the GUI. Specifically this PR:
- Adds an `Assume` check to disallow passing negative timeout values to `Mining::waitTipChanged`
- Makes `waitfornewblock`, `waitforblock` and `waitforblockheight` RPC methods usable from the GUI when `-server=1` is not set.
- Changes `Mining::waitTipChanged` to return `optional<BlockRef>` instead of `BlockRef` and return `nullopt` instead of crashing if there is a timeout or if the node is shut down before a tip is connected.
- Changes `Mining::waitTipChanged` to not time out before a tip is connected, so it is convenient and safe to call during startup, and only returns `nullopt` on early shutdowns.
- Changes `Mining::createNewBlock` to block and wait for a tip to be connected if it is called on startup instead of crashing. Also documents that it will return null on early shutdowns.
This allows `waitNext()` (added in https://github.com/bitcoin/bitcoin/pull/31283) to safely assume `TipBlock()` isn't `null`, not even during a scenario of early shutdown.
Finally this PR clarifies long poll behaviour, mostly by adding code comments, but also through an early `break`.
ACKs for top commit:
achow101:
ACK 05117e6e17
ryanofsky:
Code review ACK 05117e6e17, just updated a commit message since last review
TheCharlatan:
ACK 05117e6e17
vasild:
ACK 05117e6e17
Tree-SHA512: 277c285a6e73dfff88fd379298190b264254996f98b93c91c062986ab35c2aa5e1fbfec4cd71d7b29dc2d68e33f252b5cfc501345f54939d6bd78599b71fec04
The src/node/ directory contains code that needs to access node state
(state in CChain, CBlockIndex, CCoinsView, CTxMemPool, and similar
classes).
Code in src/node/ is meant to be segregated from code in
src/wallet/ and src/qt/, to ensure wallet and GUI
code changes don't interfere with node operation, to allow wallet and GUI code
to run in separate processes, and to perhaps eventually allow wallet and GUI
code to be maintained in separate source repositories.
As a rule of thumb, code in one of the src/node/,
src/wallet/, or src/qt/ directories should avoid
calling code in the other directories directly, and only invoke it indirectly
through the more limited src/interfaces/ classes.
This directory is at the moment
sparsely populated. Eventually more substantial files like
src/validation.cpp and
src/txmempool.cpp might be moved there.
99a4ddf5ab