Bitcoin Core  0.20.99
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Public Member Functions | Public Attributes | Private Member Functions | Private Attributes | List of all members
CChainState Class Reference

CChainState stores and provides an API to update our local knowledge of the current best chain. More...

#include <validation.h>

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Public Member Functions

 CChainState (CTxMemPool &mempool, BlockManager &blockman, uint256 from_snapshot_blockhash=uint256())
 
void InitCoinsDB (size_t cache_size_bytes, bool in_memory, bool should_wipe, std::string leveldb_name="chainstate")
 Initialize the CoinsViews UTXO set database management data structures. More...
 
CCoinsViewCacheCoinsTip () EXCLUSIVE_LOCKS_REQUIRED(cs_main)
 
CCoinsViewDBCoinsDB () EXCLUSIVE_LOCKS_REQUIRED(cs_main)
 
CCoinsViewErrorCatcherCoinsErrorCatcher () EXCLUSIVE_LOCKS_REQUIRED(cs_main)
 
void ResetCoinsViews ()
 Destructs all objects related to accessing the UTXO set. More...
 
void ForceFlushStateToDisk ()
 Unconditionally flush all changes to disk. More...
 
void PruneAndFlush ()
 Prune blockfiles from the disk if necessary and then flush chainstate changes if we pruned. More...
 
bool ActivateBestChain (BlockValidationState &state, const CChainParams &chainparams, std::shared_ptr< const CBlock > pblock) LOCKS_EXCLUDED(cs_main)
 Make the best chain active, in multiple steps. More...
 
bool AcceptBlock (const std::shared_ptr< const CBlock > &pblock, BlockValidationState &state, const CChainParams &chainparams, CBlockIndex **ppindex, bool fRequested, const FlatFilePos *dbp, bool *fNewBlock) EXCLUSIVE_LOCKS_REQUIRED(cs_main)
 Store block on disk. More...
 
DisconnectResult DisconnectBlock (const CBlock &block, const CBlockIndex *pindex, CCoinsViewCache &view)
 Undo the effects of this block (with given index) on the UTXO set represented by coins. More...
 
bool ConnectBlock (const CBlock &block, BlockValidationState &state, CBlockIndex *pindex, CCoinsViewCache &view, const CChainParams &chainparams, bool fJustCheck=false) EXCLUSIVE_LOCKS_REQUIRED(cs_main)
 Apply the effects of this block (with given index) on the UTXO set represented by coins. More...
 
bool DisconnectTip (BlockValidationState &state, const CChainParams &chainparams, DisconnectedBlockTransactions *disconnectpool) EXCLUSIVE_LOCKS_REQUIRED(cs_main
 Disconnect m_chain's tip. More...
 
bool PreciousBlock (BlockValidationState &state, const CChainParams &params, CBlockIndex *pindex) LOCKS_EXCLUDED(cs_main)
 
bool InvalidateBlock (BlockValidationState &state, const CChainParams &chainparams, CBlockIndex *pindex) LOCKS_EXCLUDED(cs_main)
 
void ResetBlockFailureFlags (CBlockIndex *pindex) EXCLUSIVE_LOCKS_REQUIRED(cs_main)
 
bool ReplayBlocks (const CChainParams &params)
 Replay blocks that aren't fully applied to the database. More...
 
bool RewindBlockIndex (const CChainParams &params) LOCKS_EXCLUDED(cs_main)
 
bool LoadGenesisBlock (const CChainParams &chainparams)
 
void PruneBlockIndexCandidates ()
 Delete all entries in setBlockIndexCandidates that are worse than the current tip. More...
 
void UnloadBlockIndex ()
 
bool IsInitialBlockDownload () const
 Check whether we are doing an initial block download (synchronizing from disk or network) More...
 
void CheckBlockIndex (const Consensus::Params &consensusParams)
 Make various assertions about the state of the block index. More...
 
void LoadMempool (const ArgsManager &args)
 Load the persisted mempool from disk. More...
 
bool LoadChainTip (const CChainParams &chainparams) EXCLUSIVE_LOCKS_REQUIRED(cs_main)
 Update the chain tip based on database information, i.e. More...
 

Public Attributes

CChain m_chain
 The current chain of blockheaders we consult and build on. More...
 
const uint256 m_from_snapshot_blockhash {}
 The blockhash which is the base of the snapshot this chainstate was created from. More...
 
std::set< CBlockIndex *, CBlockIndexWorkComparatorsetBlockIndexCandidates
 The set of all CBlockIndex entries with BLOCK_VALID_TRANSACTIONS (for itself and all ancestors) and as good as our current tip or better. More...
 
size_t m_coinsdb_cache_size_bytes {0}
 The cache size of the on-disk coins view. More...
 
size_t m_coinstip_cache_size_bytes {0}
 The cache size of the in-memory coins view. More...
 
bool m_mempool cs
 

Private Member Functions

bool ActivateBestChainStep (BlockValidationState &state, const CChainParams &chainparams, CBlockIndex *pindexMostWork, const std::shared_ptr< const CBlock > &pblock, bool &fInvalidFound, ConnectTrace &connectTrace) EXCLUSIVE_LOCKS_REQUIRED(cs_main
 Dictates whether we need to flush the cache to disk or not. More...
 
bool ConnectTip (BlockValidationState &state, const CChainParams &chainparams, CBlockIndex *pindexNew, const std::shared_ptr< const CBlock > &pblock, ConnectTrace &connectTrace, DisconnectedBlockTransactions &disconnectpool) EXCLUSIVE_LOCKS_REQUIRED(cs_main
 Connect a new block to m_chain. More...
 
void InvalidBlockFound (CBlockIndex *pindex, const BlockValidationState &state) EXCLUSIVE_LOCKS_REQUIRED(cs_main)
 
CBlockIndexFindMostWorkChain () EXCLUSIVE_LOCKS_REQUIRED(cs_main)
 Return the tip of the chain with the most work in it, that isn't known to be invalid (it's however far from certain to be valid). More...
 
void ReceivedBlockTransactions (const CBlock &block, CBlockIndex *pindexNew, const FlatFilePos &pos, const Consensus::Params &consensusParams) EXCLUSIVE_LOCKS_REQUIRED(cs_main)
 Mark a block as having its data received and checked (up to BLOCK_VALID_TRANSACTIONS). More...
 
bool RollforwardBlock (const CBlockIndex *pindex, CCoinsViewCache &inputs, const CChainParams &params) EXCLUSIVE_LOCKS_REQUIRED(cs_main)
 Apply the effects of a block on the utxo cache, ignoring that it may already have been applied. More...
 
void EraseBlockData (CBlockIndex *index) EXCLUSIVE_LOCKS_REQUIRED(cs_main)
 Mark a block as not having block data. More...
 

Private Attributes

RecursiveMutex cs_nBlockSequenceId
 Every received block is assigned a unique and increasing identifier, so we know which one to give priority in case of a fork. More...
 
int32_t nBlockSequenceId = 1
 Blocks loaded from disk are assigned id 0, so start the counter at 1. More...
 
int32_t nBlockReverseSequenceId = -1
 Decreasing counter (used by subsequent preciousblock calls). More...
 
arith_uint256 nLastPreciousChainwork = 0
 chainwork for the last block that preciousblock has been applied to. More...
 
RecursiveMutex m_cs_chainstate
 the ChainState CriticalSection A lock that must be held when modifying this ChainState - held in ActivateBestChain() More...
 
std::atomic< bool > m_cached_finished_ibd {false}
 Whether this chainstate is undergoing initial block download. More...
 
BlockManagerm_blockman
 Reference to a BlockManager instance which itself is shared across all CChainState instances. More...
 
CTxMemPoolm_mempool
 mempool that is kept in sync with the chain More...
 
std::unique_ptr< CoinsViewsm_coins_views
 Manages the UTXO set, which is a reflection of the contents of m_chain. More...
 
friend ChainstateManager
 

Detailed Description

CChainState stores and provides an API to update our local knowledge of the current best chain.

Eventually, the API here is targeted at being exposed externally as a consumable libconsensus library, so any functions added must only call other class member functions, pure functions in other parts of the consensus library, callbacks via the validation interface, or read/write-to-disk functions (eventually this will also be via callbacks).

Anything that is contingent on the current tip of the chain is stored here, whereas block information and metadata independent of the current tip is kept in BlockMetadataManager.

Definition at line 506 of file validation.h.

Constructor & Destructor Documentation

◆ CChainState()

CChainState::CChainState ( CTxMemPool mempool,
BlockManager blockman,
uint256  from_snapshot_blockhash = uint256() 
)
explicit

Definition at line 1266 of file validation.cpp.

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Member Function Documentation

◆ AcceptBlock()

bool CChainState::AcceptBlock ( const std::shared_ptr< const CBlock > &  pblock,
BlockValidationState state,
const CChainParams chainparams,
CBlockIndex **  ppindex,
bool  fRequested,
const FlatFilePos dbp,
bool *  fNewBlock 
)

Store block on disk.

If dbp is non-nullptr, the file is known to already reside on disk

Definition at line 3751 of file validation.cpp.

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◆ ActivateBestChain()

bool CChainState::ActivateBestChain ( BlockValidationState state,
const CChainParams chainparams,
std::shared_ptr< const CBlock pblock 
)

Make the best chain active, in multiple steps.

The result is either failure or an activated best chain. pblock is either nullptr or a pointer to a block that is already loaded (to avoid loading it again from disk).

ActivateBestChain is split into steps (see ActivateBestChainStep) so that we avoid holding cs_main for an extended period of time; the length of this call may be quite long during reindexing or a substantial reorg.

May not be called with cs_main held. May not be called in a validationinterface callback.

Returns
true unless a system error occurred

Definition at line 2860 of file validation.cpp.

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◆ ActivateBestChainStep()

bool CChainState::ActivateBestChainStep ( BlockValidationState state,
const CChainParams chainparams,
CBlockIndex pindexMostWork,
const std::shared_ptr< const CBlock > &  pblock,
bool &  fInvalidFound,
ConnectTrace connectTrace 
)
private

Dictates whether we need to flush the cache to disk or not.

Try to make some progress towards making pindexMostWork the active block.

Returns
the state of the size of the coins cache.

pblock is either nullptr or a pointer to a CBlock corresponding to pindexMostWork.

Returns
true unless a system error occurred

Definition at line 2734 of file validation.cpp.

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◆ CheckBlockIndex()

void CChainState::CheckBlockIndex ( const Consensus::Params consensusParams)

Make various assertions about the state of the block index.

By default this only executes fully when using the Regtest chain; see: fCheckBlockIndex.

Definition at line 4781 of file validation.cpp.

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◆ CoinsDB()

CCoinsViewDB& CChainState::CoinsDB ( )
inline
Returns
A reference to the on-disk UTXO set database.

Definition at line 597 of file validation.h.

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◆ CoinsErrorCatcher()

CCoinsViewErrorCatcher& CChainState::CoinsErrorCatcher ( )
inline
Returns
A reference to a wrapped view of the in-memory UTXO set that handles disk read errors gracefully.

Definition at line 604 of file validation.h.

◆ CoinsTip()

CCoinsViewCache& CChainState::CoinsTip ( )
inline
Returns
A reference to the in-memory cache of the UTXO set.

Definition at line 590 of file validation.h.

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◆ ConnectBlock()

bool CChainState::ConnectBlock ( const CBlock block,
BlockValidationState state,
CBlockIndex pindex,
CCoinsViewCache view,
const CChainParams chainparams,
bool  fJustCheck = false 
)

Apply the effects of this block (with given index) on the UTXO set represented by coins.

Validity checks that depend on the UTXO set are also done; ConnectBlock() can fail if those validity checks fail (among other reasons).

Definition at line 1938 of file validation.cpp.

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◆ ConnectTip()

bool CChainState::ConnectTip ( BlockValidationState state,
const CChainParams chainparams,
CBlockIndex pindexNew,
const std::shared_ptr< const CBlock > &  pblock,
ConnectTrace connectTrace,
DisconnectedBlockTransactions disconnectpool 
)
private

Connect a new block to m_chain.

pblock is either nullptr or a pointer to a CBlock corresponding to pindexNew, to bypass loading it again from disk.

The block is added to connectTrace if connection succeeds.

Definition at line 2598 of file validation.cpp.

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◆ DisconnectBlock()

DisconnectResult CChainState::DisconnectBlock ( const CBlock block,
const CBlockIndex pindex,
CCoinsViewCache view 
)

Undo the effects of this block (with given index) on the UTXO set represented by coins.

When FAILED is returned, view is left in an indeterminate state.

Definition at line 1712 of file validation.cpp.

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◆ DisconnectTip()

bool CChainState::DisconnectTip ( BlockValidationState state,
const CChainParams chainparams,
DisconnectedBlockTransactions disconnectpool 
)

Disconnect m_chain's tip.

After calling, the mempool will be in an inconsistent state, with transactions from disconnected blocks being added to disconnectpool. You should make the mempool consistent again by calling UpdateMempoolForReorg. with cs_main held.

If disconnectpool is nullptr, then no disconnected transactions are added to disconnectpool (note that the caller is responsible for mempool consistency in any case).

Definition at line 2497 of file validation.cpp.

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◆ EraseBlockData()

void CChainState::EraseBlockData ( CBlockIndex index)
private

Mark a block as not having block data.

Helper for CChainState::RewindBlockIndex.

Definition at line 4445 of file validation.cpp.

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◆ FindMostWorkChain()

CBlockIndex * CChainState::FindMostWorkChain ( )
private

Return the tip of the chain with the most work in it, that isn't known to be invalid (it's however far from certain to be valid).

Definition at line 2661 of file validation.cpp.

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◆ ForceFlushStateToDisk()

void CChainState::ForceFlushStateToDisk ( )

Unconditionally flush all changes to disk.

Definition at line 2403 of file validation.cpp.

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◆ InitCoinsDB()

void CChainState::InitCoinsDB ( size_t  cache_size_bytes,
bool  in_memory,
bool  should_wipe,
std::string  leveldb_name = "chainstate" 
)

Initialize the CoinsViews UTXO set database management data structures.

The in-memory cache is initialized separately.

All parameters forwarded to CoinsViews.

Definition at line 1271 of file validation.cpp.

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◆ InvalidateBlock()

bool CChainState::InvalidateBlock ( BlockValidationState state,
const CChainParams chainparams,
CBlockIndex pindex 
)

Definition at line 2994 of file validation.cpp.

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◆ InvalidBlockFound()

void CChainState::InvalidBlockFound ( CBlockIndex pindex,
const BlockValidationState state 
)
private

Definition at line 1437 of file validation.cpp.

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◆ IsInitialBlockDownload()

bool CChainState::IsInitialBlockDownload ( ) const

Check whether we are doing an initial block download (synchronizing from disk or network)

Definition at line 1297 of file validation.cpp.

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◆ LoadChainTip()

bool CChainState::LoadChainTip ( const CChainParams chainparams)

Update the chain tip based on database information, i.e.

CoinsTip()'s best block.

Definition at line 4220 of file validation.cpp.

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◆ LoadGenesisBlock()

bool CChainState::LoadGenesisBlock ( const CChainParams chainparams)

Definition at line 4632 of file validation.cpp.

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◆ LoadMempool()

void CChainState::LoadMempool ( const ArgsManager args)

Load the persisted mempool from disk.

Definition at line 4212 of file validation.cpp.

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◆ PreciousBlock()

bool CChainState::PreciousBlock ( BlockValidationState state,
const CChainParams params,
CBlockIndex pindex 
)

Definition at line 2962 of file validation.cpp.

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◆ PruneAndFlush()

void CChainState::PruneAndFlush ( )

Prune blockfiles from the disk if necessary and then flush chainstate changes if we pruned.

Definition at line 2411 of file validation.cpp.

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◆ PruneBlockIndexCandidates()

void CChainState::PruneBlockIndexCandidates ( )

Delete all entries in setBlockIndexCandidates that are worse than the current tip.

Definition at line 2717 of file validation.cpp.

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◆ ReceivedBlockTransactions()

void CChainState::ReceivedBlockTransactions ( const CBlock block,
CBlockIndex pindexNew,
const FlatFilePos pos,
const Consensus::Params consensusParams 
)
private

Mark a block as having its data received and checked (up to BLOCK_VALID_TRANSACTIONS).

Definition at line 3209 of file validation.cpp.

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◆ ReplayBlocks()

bool CChainState::ReplayBlocks ( const CChainParams params)

Replay blocks that aren't fully applied to the database.

Definition at line 4377 of file validation.cpp.

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◆ ResetBlockFailureFlags()

void CChainState::ResetBlockFailureFlags ( CBlockIndex pindex)

Definition at line 3134 of file validation.cpp.

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◆ ResetCoinsViews()

void CChainState::ResetCoinsViews ( )
inline

Destructs all objects related to accessing the UTXO set.

Definition at line 610 of file validation.h.

◆ RewindBlockIndex()

bool CChainState::RewindBlockIndex ( const CChainParams params)

Definition at line 4480 of file validation.cpp.

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◆ RollforwardBlock()

bool CChainState::RollforwardBlock ( const CBlockIndex pindex,
CCoinsViewCache inputs,
const CChainParams params 
)
private

Apply the effects of a block on the utxo cache, ignoring that it may already have been applied.

Definition at line 4357 of file validation.cpp.

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◆ UnloadBlockIndex()

void CChainState::UnloadBlockIndex ( )

Definition at line 4583 of file validation.cpp.

Member Data Documentation

◆ ChainstateManager

friend CChainState::ChainstateManager
private

Definition at line 732 of file validation.h.

◆ cs

bool m_mempool CChainState::cs

Definition at line 674 of file validation.h.

◆ cs_nBlockSequenceId

RecursiveMutex CChainState::cs_nBlockSequenceId
private

Every received block is assigned a unique and increasing identifier, so we know which one to give priority in case of a fork.

Definition at line 513 of file validation.h.

◆ m_blockman

BlockManager& CChainState::m_blockman
private

Reference to a BlockManager instance which itself is shared across all CChainState instances.

Keeping a local reference allows us to test more easily as opposed to referencing a global.

Definition at line 538 of file validation.h.

◆ m_cached_finished_ibd

std::atomic<bool> CChainState::m_cached_finished_ibd {false}
mutableprivate

Whether this chainstate is undergoing initial block download.

Mutable because we need to be able to mark IsInitialBlockDownload() const, which latches this for caching purposes.

Definition at line 533 of file validation.h.

◆ m_chain

CChain CChainState::m_chain

The current chain of blockheaders we consult and build on.

See also
CChain, CBlockIndex.

Definition at line 573 of file validation.h.

◆ m_coins_views

std::unique_ptr<CoinsViews> CChainState::m_coins_views
private

Manages the UTXO set, which is a reflection of the contents of m_chain.

Definition at line 544 of file validation.h.

◆ m_coinsdb_cache_size_bytes

size_t CChainState::m_coinsdb_cache_size_bytes {0}

The cache size of the on-disk coins view.

Definition at line 613 of file validation.h.

◆ m_coinstip_cache_size_bytes

size_t CChainState::m_coinstip_cache_size_bytes {0}

The cache size of the in-memory coins view.

Definition at line 616 of file validation.h.

◆ m_cs_chainstate

RecursiveMutex CChainState::m_cs_chainstate
private

the ChainState CriticalSection A lock that must be held when modifying this ChainState - held in ActivateBestChain()

Definition at line 525 of file validation.h.

◆ m_from_snapshot_blockhash

const uint256 CChainState::m_from_snapshot_blockhash {}

The blockhash which is the base of the snapshot this chainstate was created from.

IsNull() if this chainstate was not created from a snapshot.

Definition at line 580 of file validation.h.

◆ m_mempool

CTxMemPool& CChainState::m_mempool
private

mempool that is kept in sync with the chain

Definition at line 541 of file validation.h.

◆ nBlockReverseSequenceId

int32_t CChainState::nBlockReverseSequenceId = -1
private

Decreasing counter (used by subsequent preciousblock calls).

Definition at line 517 of file validation.h.

◆ nBlockSequenceId

int32_t CChainState::nBlockSequenceId = 1
private

Blocks loaded from disk are assigned id 0, so start the counter at 1.

Definition at line 515 of file validation.h.

◆ nLastPreciousChainwork

arith_uint256 CChainState::nLastPreciousChainwork = 0
private

chainwork for the last block that preciousblock has been applied to.

Definition at line 519 of file validation.h.

◆ setBlockIndexCandidates

std::set<CBlockIndex*, CBlockIndexWorkComparator> CChainState::setBlockIndexCandidates

The set of all CBlockIndex entries with BLOCK_VALID_TRANSACTIONS (for itself and all ancestors) and as good as our current tip or better.

Entries may be failed, though, and pruning nodes may be missing the data for the block.

Definition at line 587 of file validation.h.


The documentation for this class was generated from the following files: