The `PopulateAndValidateSnapshot` function introduced in
f6e2da5fb7 from #19806 has been setting fake
`nTx` and `nChainTx` values that can show up in RPC results (see #29328) and
make `CBlockIndex` state hard to reason about, because it is difficult to know
whether the values are real or fake.
Revert to previous behavior of setting `nTx` and `nChainTx` to 0 when the
values are unknown, instead of faking them.
This commit fixes at least two assert failures in the (pindex->nChainTx ==
pindex->nTx + prev_chain_tx) check that would happen previously. Tests for
these failures are added separately in the next two commits.
Compatibility note: This change could result in -checkblockindex failures if a
snapshot was loaded by a previous version of Bitcoin Core and not fully
validated, because fake nTx values will have been saved to the block index. It
would be pretty easy to avoid these failures by adding some compatibility code
to `LoadBlockIndex` and changing `nTx` values from 1 to 0 when they are fake
(when `(pindex->nStatus & BLOCK_VALID_MASK) < BLOCK_VALID_TRANSACTIONS`), but a
little simpler not to worry about being compatible in this case.
This is done in preparation for the next two commits, where the
CMainSignals are de-globalized.
This avoids adding new constructor arguments to the ChainstateManager
and CTxMemPool classes over the next two commits.
This could also allow future tests that are only interested in the
internal behaviour of the classes to forgo instantiating the signals.
Use SignalInterrupt object instead. There is a slight change in behavior here
because the previous StartShutdown code used to abort on failure and the
new code logs errors instead.
Add NodeContext::shutdown variable and start using it to replace the
kernel::Context::interrupt variable. The latter can't easily be removed right
away but will be removed later in this PR.
Moving the interrupt object from the kernel context to the node context
increases flexibility of the kernel API so it is possible to use multiple
interrupt objects, or avoid creating one if one is not needed. It will also
allow getting rid of the kernel::g_context global later in this PR, replacing
it with a private SignalInterrupt instance in init.cpp
There is no change in behavior in this commit outside of unit tests. In unit
tests there should be no visible change either, but internally now each test
has its own interrupt variable so the variable will be automatically reset
between tests.
In future commits, loading the block index while making use of a
snapshot is contingent on the snapshot being recognized by chainparams.
Ensure all existing unittests that use snapshots use a recognized
snapshot (at height 110).
Co-authored-by: Ryan Ofsky <ryan@ofsky.org>
This allows us to reference assumeutxo configuration by blockhash as
well as height; this is helpful in future changes when we want to
reference assumeutxo configurations before the block index is loaded.
This change makes IsInitialBlockDownload and NotifyHeaderTip functions no
longer tied to individual Chainstate objects. It makes them work with the
ChainstateManager object instead so code is simpler and it is no longer
possible to call them incorrectly with an inactive Chainstate.
This change also makes m_cached_finished_ibd caching easier to reason about,
because now there is only one cached value instead of two (for background and
snapshot chainstates) so the cached IBD state now no longer gets reset when a
snapshot is loaded.
There should be no change in behavior because these functions were always
called on the active ChainState objects.
These changes were discussed previously
https://github.com/bitcoin/bitcoin/pull/27746#discussion_r1246868905 and
https://github.com/bitcoin/bitcoin/pull/27746#discussion_r1237552792 as
possible followups for that PR.
When using assumeutxo and multiple chainstates are active, the background
chainstate should consider all HAVE_DATA blocks that are ancestors of the
snapshotted block and that have more work than the tip as potential candidates.
When using assumeutxo, we only need the background chainstate to consider
blocks that are on the chain leading to the snapshotted block.
Note that this introduces the new invariant that we can only have an assumeutxo
snapshot where the snapshotted blockhash is in our block index. Unknown block
hashes that are somehow passed in will cause assertion failures when processing
new blocks.
Includes test fixes and improvements by Andrew Chow and Fabian Jahr.
Block arrival information (and the preciousblock RPC, a related concept) are
both chainstate-agnostic, so these are moved to ChainstateManager. This should
just be a refactor, without any observable behavior changes.
