6082c84713
Make Chainstate objects aware of what block they are targeting. This makes Chainstate objects more self contained, so it's possible for validation code to look at one Chainstate object and know what blocks to connect to it without needing to consider global validation state or look at other Chainstate objects. The motivation for this change is to make validation and networking code more readable, so understanding it just requires knowing about chains and blocks, not reasoning about assumeutxo download states. This change also enables simplifications to the ChainstateManager interface in subsequent commits, and could make it easier to implement new features like creating new Chainstate objects to generate UTXO snapshots or index UTXO data. Note that behavior of the MaybeCompleteSnapshotValidation function is not changing here but some checks that were previously impossible to trigger like the BASE_BLOCKHASH_MISMATCH case have been turned into asserts.
src/node/
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.