Bitcoin Core  24.99.0
P2P Digital Currency
Classes | Public Member Functions | Protected Member Functions | Protected Attributes | Private Member Functions | Private Attributes | List of all members
BaseIndex Class Referenceabstract

Base class for indices of blockchain data. More...

#include <base.h>

Inheritance diagram for BaseIndex:
[legend]
Collaboration diagram for BaseIndex:
[legend]

Classes

class  DB
 The database stores a block locator of the chain the database is synced to so that the index can efficiently determine the point it last stopped at. More...
 

Public Member Functions

 BaseIndex (std::unique_ptr< interfaces::Chain > chain, std::string name)
 
virtual ~BaseIndex ()
 Destructor interrupts sync thread if running and blocks until it exits. More...
 
bool Start ()
 Start initializes the sync state and registers the instance as a ValidationInterface so that it stays in sync with blockchain updates. More...
 
void Stop ()
 Stops the instance from staying in sync with blockchain updates. More...
 
IndexSummary GetSummary () const
 Get a summary of the index and its state. More...
 

Protected Member Functions

void BlockConnected (const std::shared_ptr< const CBlock > &block, const CBlockIndex *pindex) override
 Notifies listeners of a block being connected. More...
 
void ChainStateFlushed (const CBlockLocator &locator) override
 Notifies listeners of the new active block chain on-disk. More...
 
virtual bool CustomInit (const std::optional< interfaces::BlockKey > &block)
 Initialize internal state from the database and block index. More...
 
virtual bool CustomAppend (const interfaces::BlockInfo &block)
 Write update index entries for a newly connected block. More...
 
virtual bool CustomCommit (CDBBatch &batch)
 Virtual method called internally by Commit that can be overridden to atomically commit more index state. More...
 
virtual bool CustomRewind (const interfaces::BlockKey &current_tip, const interfaces::BlockKey &new_tip)
 Rewind index to an earlier chain tip during a chain reorg. More...
 
virtual DBGetDB () const =0
 
const std::string & GetName () const LIFETIMEBOUND
 Get the name of the index for display in logs. More...
 
void SetBestBlockIndex (const CBlockIndex *block)
 Update the internal best block index as well as the prune lock. More...
 
- Protected Member Functions inherited from CValidationInterface
 ~CValidationInterface ()=default
 Protected destructor so that instances can only be deleted by derived classes. More...
 
virtual void UpdatedBlockTip (const CBlockIndex *pindexNew, const CBlockIndex *pindexFork, bool fInitialDownload)
 Notifies listeners when the block chain tip advances. More...
 
virtual void TransactionAddedToMempool (const CTransactionRef &tx, uint64_t mempool_sequence)
 Notifies listeners of a transaction having been added to mempool. More...
 
virtual void TransactionRemovedFromMempool (const CTransactionRef &tx, MemPoolRemovalReason reason, uint64_t mempool_sequence)
 Notifies listeners of a transaction leaving mempool. More...
 
virtual void BlockDisconnected (const std::shared_ptr< const CBlock > &block, const CBlockIndex *pindex)
 Notifies listeners of a block being disconnected. More...
 
virtual void BlockChecked (const CBlock &, const BlockValidationState &)
 Notifies listeners of a block validation result. More...
 
virtual void NewPoWValidBlock (const CBlockIndex *pindex, const std::shared_ptr< const CBlock > &block)
 Notifies listeners that a block which builds directly on our current tip has been received and connected to the headers tree, though not validated yet. More...
 

Protected Attributes

std::unique_ptr< interfaces::Chainm_chain
 
Chainstatem_chainstate {nullptr}
 
const std::string m_name
 

Private Member Functions

bool Init ()
 Read best block locator and check that data needed to sync has not been pruned. More...
 
void ThreadSync ()
 Sync the index with the block index starting from the current best block. More...
 
bool Commit ()
 Write the current index state (eg. More...
 
bool Rewind (const CBlockIndex *current_tip, const CBlockIndex *new_tip)
 Loop over disconnected blocks and call CustomRewind. More...
 
virtual bool AllowPrune () const =0
 

Private Attributes

std::atomic< bool > m_synced {false}
 Whether the index is in sync with the main chain. More...
 
std::atomic< const CBlockIndex * > m_best_block_index {nullptr}
 The last block in the chain that the index is in sync with. More...
 
std::thread m_thread_sync
 
CThreadInterrupt m_interrupt
 

Detailed Description

Base class for indices of blockchain data.

This implements CValidationInterface and ensures blocks are indexed sequentially according to their position in the active chain.

Definition at line 33 of file base.h.

Constructor & Destructor Documentation

◆ BaseIndex()

BaseIndex::BaseIndex ( std::unique_ptr< interfaces::Chain chain,
std::string  name 
)

Definition at line 68 of file base.cpp.

◆ ~BaseIndex()

BaseIndex::~BaseIndex ( )
virtual

Destructor interrupts sync thread if running and blocks until it exits.

Definition at line 71 of file base.cpp.

Here is the call graph for this function:

Member Function Documentation

◆ AllowPrune()

virtual bool BaseIndex::AllowPrune ( ) const
privatepure virtual

Implemented in TxIndex, CoinStatsIndex, and BlockFilterIndex.

Here is the caller graph for this function:

◆ BlockConnected()

void BaseIndex::BlockConnected ( const std::shared_ptr< const CBlock > &  block,
const CBlockIndex pindex 
)
overrideprotectedvirtual

Notifies listeners of a block being connected.

Provides a vector of transactions evicted from the mempool as a result.

Called on a background thread.

Reimplemented from CValidationInterface.

Definition at line 267 of file base.cpp.

Here is the call graph for this function:

◆ ChainStateFlushed()

void BaseIndex::ChainStateFlushed ( const CBlockLocator locator)
overrideprotectedvirtual

Notifies listeners of the new active block chain on-disk.

Prior to this callback, any updates are not guaranteed to persist on disk (ie clients need to handle shutdown/restart safety by being able to understand when some updates were lost due to unclean shutdown).

When this callback is invoked, the validation changes done by any prior callback are guaranteed to exist on disk and survive a restart, including an unclean shutdown.

Provides a locator describing the best chain, which is likely useful for storing current state on disk in client DBs.

Called on a background thread.

Reimplemented from CValidationInterface.

Definition at line 313 of file base.cpp.

Here is the call graph for this function:

◆ Commit()

bool BaseIndex::Commit ( )
private

Write the current index state (eg.

chain block locator and subclass-specific items) to disk.

Recommendations for error handling: If called on a successor of the previous committed best block in the index, the index can continue processing without risk of corruption, though the index state will need to catch up from further behind on reboot. If the new state is not a successor of the previous state (due to a chain reorganization), the index must halt until Commit succeeds or else it could end up getting corrupted.

Definition at line 224 of file base.cpp.

Here is the call graph for this function:
Here is the caller graph for this function:

◆ CustomAppend()

virtual bool BaseIndex::CustomAppend ( const interfaces::BlockInfo block)
inlineprotectedvirtual

Write update index entries for a newly connected block.

Reimplemented in TxIndex, CoinStatsIndex, and BlockFilterIndex.

Definition at line 110 of file base.h.

Here is the caller graph for this function:

◆ CustomCommit()

virtual bool BaseIndex::CustomCommit ( CDBBatch batch)
inlineprotectedvirtual

Virtual method called internally by Commit that can be overridden to atomically commit more index state.

Reimplemented in CoinStatsIndex, and BlockFilterIndex.

Definition at line 114 of file base.h.

Here is the caller graph for this function:

◆ CustomInit()

virtual bool BaseIndex::CustomInit ( const std::optional< interfaces::BlockKey > &  block)
inlineprotectedvirtual

Initialize internal state from the database and block index.

Reimplemented in CoinStatsIndex, and BlockFilterIndex.

Definition at line 107 of file base.h.

Here is the caller graph for this function:

◆ CustomRewind()

virtual bool BaseIndex::CustomRewind ( const interfaces::BlockKey current_tip,
const interfaces::BlockKey new_tip 
)
inlineprotectedvirtual

Rewind index to an earlier chain tip during a chain reorg.

The tip must be an ancestor of the current best block.

Reimplemented in CoinStatsIndex, and BlockFilterIndex.

Definition at line 118 of file base.h.

Here is the caller graph for this function:

◆ GetDB()

virtual DB& BaseIndex::GetDB ( ) const
protectedpure virtual

Implemented in TxIndex, CoinStatsIndex, and BlockFilterIndex.

Here is the caller graph for this function:

◆ GetName()

const std::string& BaseIndex::GetName ( ) const
inlineprotected

Get the name of the index for display in logs.

Definition at line 123 of file base.h.

Here is the caller graph for this function:

◆ GetSummary()

IndexSummary BaseIndex::GetSummary ( ) const

Get a summary of the index and its state.

Definition at line 409 of file base.cpp.

Here is the call graph for this function:
Here is the caller graph for this function:

◆ Init()

bool BaseIndex::Init ( )
private

Read best block locator and check that data needed to sync has not been pruned.

Definition at line 77 of file base.cpp.

Here is the call graph for this function:
Here is the caller graph for this function:

◆ Rewind()

bool BaseIndex::Rewind ( const CBlockIndex current_tip,
const CBlockIndex new_tip 
)
private

Loop over disconnected blocks and call CustomRewind.

Definition at line 243 of file base.cpp.

Here is the call graph for this function:
Here is the caller graph for this function:

◆ SetBestBlockIndex()

void BaseIndex::SetBestBlockIndex ( const CBlockIndex block)
protected

Update the internal best block index as well as the prune lock.

Definition at line 418 of file base.cpp.

Here is the call graph for this function:
Here is the caller graph for this function:

◆ Start()

bool BaseIndex::Start ( )

Start initializes the sync state and registers the instance as a ValidationInterface so that it stays in sync with blockchain updates.

Definition at line 381 of file base.cpp.

Here is the call graph for this function:
Here is the caller graph for this function:

◆ Stop()

void BaseIndex::Stop ( )

Stops the instance from staying in sync with blockchain updates.

Definition at line 400 of file base.cpp.

Here is the call graph for this function:
Here is the caller graph for this function:

◆ ThreadSync()

void BaseIndex::ThreadSync ( )
private

Sync the index with the block index starting from the current best block.

Intended to be run in its own thread, m_thread_sync, and can be interrupted with m_interrupt. Once the index gets in sync, the m_synced flag is set and the BlockConnected ValidationInterface callback takes over and the sync thread exits.

Definition at line 149 of file base.cpp.

Here is the call graph for this function:
Here is the caller graph for this function:

Member Data Documentation

◆ m_best_block_index

std::atomic<const CBlockIndex*> BaseIndex::m_best_block_index {nullptr}
private

The last block in the chain that the index is in sync with.

Definition at line 67 of file base.h.

◆ m_chain

std::unique_ptr<interfaces::Chain> BaseIndex::m_chain
protected

Definition at line 98 of file base.h.

◆ m_chainstate

Chainstate* BaseIndex::m_chainstate {nullptr}
protected

Definition at line 99 of file base.h.

◆ m_interrupt

CThreadInterrupt BaseIndex::m_interrupt
private

Definition at line 70 of file base.h.

◆ m_name

const std::string BaseIndex::m_name
protected

Definition at line 100 of file base.h.

◆ m_synced

std::atomic<bool> BaseIndex::m_synced {false}
private

Whether the index is in sync with the main chain.

The flag is flipped from false to true once, after which point this starts processing ValidationInterface notifications to stay in sync.

Note that this will latch to true immediately upon startup if m_chainstate->m_chain is empty, which will be the case upon startup with an empty datadir if, e.g., -txindex=1 is specified.

Definition at line 64 of file base.h.

◆ m_thread_sync

std::thread BaseIndex::m_thread_sync
private

Definition at line 69 of file base.h.


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