and mark the inherited CBlockIndex#GetBlockHash public interface member
as deleted, to disallow calling it in the derived CDiskBlockIndex class.
Here is a failing test on master demonstrating the inconsistent behavior of the
current design: calling the same inherited public interface functions on the
same CDiskBlockIndex object should yield identical behavior.
```diff
diff --git a/src/test/validation_chainstatemanager_tests.cpp b/src/test/validation_chainstatemanager_tests.cpp
index 6dc522b421..dac3840f32 100644
--- a/src/test/validation_chainstatemanager_tests.cpp
+++ b/src/test/validation_chainstatemanager_tests.cpp
@@ -240,6 +240,15 @@ BOOST_FIXTURE_TEST_CASE(chainstatemanager_activate_snapshot, TestChain100Setup)
const CBlockIndex* tip = chainman.ActiveTip();
BOOST_CHECK_EQUAL(tip->nChainTx, au_data.nChainTx);
+ // CDiskBlockIndex "is a" CBlockIndex, as it publicly inherits from it.
+ // Test that calling the same inherited interface functions on the same
+ // object yields identical behavior.
+ CDiskBlockIndex index{tip};
+ CBlockIndex *pB = &index;
+ CDiskBlockIndex *pD = &index;
+ BOOST_CHECK_EQUAL(pB->GetBlockHash(), pD->GetBlockHash());
+ BOOST_CHECK_EQUAL(pB->ToString(), pD->ToString());
+
```
The GetBlockHash() test assertion only passes on master because the different
methods invoked by the current design happen to return the same result. If one
of the two is changed, it fails like the ToString() assertion does.
Redefining inherited non-virtual functions is well-documented as incorrect
design to avoid inconsistent behavior (see Scott Meyers, "Effective C++", Item
36). Class usage is confusing when the behavior depends on the pointer
definition instead of the object definition (static binding happening where
dynamic binding was expected). This can lead to unsuspected or hard-to-track
bugs.
Outside of critical hot spots, correctness usually comes before optimisation,
but the current design dates back to main.cpp and it may possibly have been
chosen to avoid the overhead of dynamic dispatch. This solution does the same:
the class sizes are unchanged and no vptr or vtbl is added.
There are better designs for doing this that use composition instead of
inheritance or that separate the public interface from the private
implementations. One example of the latter would be a non-virtual public
interface that calls private virtual implementation methods, i.e. the Template
pattern via the Non-Virtual Interface (NVI) idiom.
These methods haven't been used since the chainstate db cache has been
switched from per-tx to per-txout model years ago (PR #10195, commit
d342424301).
fa9112aac0 Remove utxo db upgrade code (MarcoFalke)
Pull request description:
It is not possible to upgrade Bitcoin Core pre-segwit (pre-0.13.1) to a recent version without a full IBD from scratch after commit 19a56d1519 (released in version 22.0).
Any Bitcoin Core version with the new database format after commit 1088b02f0c (released in version 0.15), can upgrade to any version that is supported as of today.
This leaves the versions 0.13.1-0.14.x. Even though those versions are unsupported, some users with an existing datadir may want to upgrade to a recent version. However, it seems reasonable to simply ask them to `-reindex` to run a full IBD from scratch. This allows us to remove the utxo db upgrade code.
ACKs for top commit:
Sjors:
re-ACK fa9112aac0
laanwj:
Code review ACK fa9112aac0
Tree-SHA512: 4243bb35df9ac4892f9fad30fe486d338745952bcff4160bcb0937c772d57b13b800647da14695e21e3655e85ee0d95fa3dc7789ee309d59ad84f422297fecb8
Improve readability of code, simplify future scripted diff cleanup PRs, and be
more consistent with naming for GetBoolArg.
This will also be useful for replacing runtime settings type checking
with compile time checking.
-BEGIN VERIFY SCRIPT-
git grep -l GetArg | xargs sed -i 's/GetArg(\([^)]*\( [0-9]\+\|-1\|port\|BaseParams().RPCPort()\|Params().GetDefaultPort()\|_TIMEOUT\|Height\|_WORKQUEUE\|_THREADS\|_CONNECTIONS\|LIMIT\|SigOp\|Bytes\|_VERSION\|_AGE\|_CHECKS\|Checks() ? 1 : 0\|_BANTIME\|Cache\|BLOCKS\|LEVEL\|Weight\|Version\|BUFFER\|TARGET\|WEIGHT\|TXN\|TRANSACTIONS\|ADJUSTMENT\|i64\|Size\|nDefault\|_EXPIRY\|HEIGHT\|SIZE\|SNDHWM\|_TIME_MS\)\))/GetIntArg(\1)/g'
-END VERIFY SCRIPT-
Co-authored-by: Hennadii Stepanov <32963518+hebasto@users.noreply.github.com>
- Finish removing all references to 'recheckpeginblockinterval', including
documentation and tests.
- Remove periodic calls to MainchainRPCCheck; use it only at startup (and
refactor accordingly to simplify logic.)
- Move MainchainRPCCheck from validation.h/cpp (public) to an internal
helper function of init.cpp.
- Comment out definition of 'revalidation queue' type in txdb, to suppress
"unused variable" warning. (Leave it visible to avoid future reuse.)
Currently, if -validatepegin is given, and block validation can't proceed
because the parent chain is not synced, we mark the block invalid and put
it in a queue to be "revalidated" later. Unfortunately, marking a block
invalid has downstream consequences, in particular causing descendant blocks
to be marked invalid, which are not currently fixed by the queue.
Instead, we'll use a different strategy: if the mainchain daemon isn't
sufficiently synced to validate a block, we will "stall" connecting that
block to the chain, and have ActivateBestChain simply keep the tip at the
previous block until we're ready.
We can still download and validate (partly) blocks past this point while
we're waiting. They will be connected once the parent chain daemon catches
up.
Looks like James hardcoded a couple hashes in hard-to-find places, which
caused a unit test to fail. I just changed the hash (which covers UTXO
data which naturally will be different for us on account of our differently
formatted CTxOuts).
TODO: determine how Assumeutxo interacts with the fact that we don't save
out nonces in our normal UTXO serialization. Probably we will need to remove
the nonce from the CCoinStats serialization to avoid having inconsistent
hashes across nodes, since these hashes are now checked in assumeutxo?
We can't support a reset of the dbwrapper object when in-memory configuration is used
because it results in the permanent loss of coins. This only affects unittest
configurations (since that's the only place we use in-memory CCoinsViewDB instances).
FIXME: we disable standardness checks for the non-PAK node in the PAK tests.
This is because of a bug in Elements which causes non-PAK nodes to reject
pegouts for standardness reasons. Need to fix it after the rebase.
f19fdd47a6 test: add test for CChainState::ResizeCoinsCaches() (James O'Beirne)
8ac3ef4699 add ChainstateManager::MaybeRebalanceCaches() (James O'Beirne)
f36aaa6392 Add CChainState::ResizeCoinsCaches (James O'Beirne)
b223111da2 txdb: add CCoinsViewDB::ChangeCacheSize (James O'Beirne)
Pull request description:
This is part of the [assumeutxo project](https://github.com/bitcoin/bitcoin/projects/11):
Parent PR: #15606
Issue: #15605
Specification: https://github.com/jamesob/assumeutxo-docs/tree/master/proposal
---
In the assumeutxo implementation draft (#15056), once a UTXO snapshot is loaded, a new chainstate object is created after initialization. This means that we have to reclaim some of the cache that we've allocated to the original chainstate (per `dbcache=`) to repurpose for the snapshot chainstate.
Furthermore, it makes sense to have different cache allocations depending on which chainstate is more active. While the snapshot chainstate is working to get to the network tip (and the background validation chainstate is idle), it makes sense that the snapshot chainstate should have the majority of cache allocation. And contrariwise once the snapshot has reached network tip, most of the cache should be given to the background validation chainstate.
This set of changes (detailed in the commit messages) allows us to dynamically resize the various coins caches. None of the functionality introduced here is used at the moment, but will be in the next AU PR (which introduces `ActivateSnapshot`).
`ChainstateManager::MaybeRebalanceCaches()` defines the (somewhat normative) cache allocations between the snapshot and background validation chainstates. I'd be interested in feedback if anyone has thoughts on the proportions I've set there.
ACKs for top commit:
ajtowns:
weak utACK f19fdd47a6 -- didn't find any major problems, but not super confident that I didn't miss anything
fjahr:
Code review ACK f19fdd4
ryanofsky:
Code review ACK f19fdd47a6. Only change since last review is constructor cleanup (no change in behavior). I think the suggestions here from ajtowns and others are good, but shouldn't delay merging the PR (and hold up assumeutxo)
Tree-SHA512: fffb7847fb6993dd4a1a41cf11179b211b0b20b7eb5f7cf6266442136bfe9d43b830bbefcafd475bfd4af273f5573500594aa41fff03e0ed5c2a1e8562ff9269
We'll need this to dynamically update the cache size of the existing
CCoinsViewDB instance when we create a new one during snapshot activation.
This requires us to keep the CDBWrapper instance as a pointer instead of
a reference so that we're able to destruct it and create a new instance
when the cache size changes.
Also renames `db` to `m_db` since we're already modifying each usage.
Includes feedback from Russ Yanofsky.
f9ee0f37c2 Add comments to CustomUintFormatter (Pieter Wuille)
4eb5643e35 Convert everything except wallet/qt to new serialization (Pieter Wuille)
2b1f85e8c5 Convert blockencodings_tests to new serialization (Pieter Wuille)
73747afbbe Convert merkleblock to new serialization (Pieter Wuille)
d06fedd1bc Add SER_READ and SER_WRITE for read/write-dependent statements (Russell Yanofsky)
6f9a1e5ad0 Extend CustomUintFormatter to support enums (Russell Yanofsky)
769ee5fa00 Merge BigEndian functionality into CustomUintFormatter (Pieter Wuille)
Pull request description:
The next step of changes from #10785.
This:
* Adds support for enum serialization to `CustomUintFormatter`, used in `CAddress` for service flags.
* Merges `BigEndian` into `CustomUintFormatter`, used in `CNetAddr` for port numbers.
* Converts everything (except wallet and gui) to use the new serialization framework.
ACKs for top commit:
MarcoFalke:
re-ACK f9ee0f37c2, only change is new documentation commit for CustomUintFormatter 📂
ryanofsky:
Code review ACK f9ee0f37c2. Just new commit adding comment since last review
jonatack:
Code review re-ACK f9ee0f37c2 only change since last review is an additional commit adding Doxygen documentation for `CustomUintFormatter`.
Tree-SHA512: e7a0a36afae592d5a4ff8c81ae04d858ac409388e361f2bc197d9a78abca45134218497ab2dfd6d031e0cce0ca586cf857077b7c6ce17fccf67e2d367c1b6cd4
