Bitcoin ABC  0.28.12
P2P Digital Currency
base.h
Go to the documentation of this file.
1 // Copyright (c) 2017-2018 The Bitcoin Core developers
2 // Distributed under the MIT software license, see the accompanying
3 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
4 
5 #ifndef BITCOIN_INDEX_BASE_H
6 #define BITCOIN_INDEX_BASE_H
7 
8 #include <dbwrapper.h>
9 #include <threadinterrupt.h>
10 #include <validationinterface.h>
11 
12 class CBlock;
13 class CBlockIndex;
14 class Chainstate;
15 
16 struct IndexSummary {
17  std::string name;
18  bool synced{false};
20 };
21 
28 protected:
36  class DB : public CDBWrapper {
37  public:
38  DB(const fs::path &path, size_t n_cache_size, bool f_memory = false,
39  bool f_wipe = false, bool f_obfuscate = false);
40 
42  bool ReadBestBlock(CBlockLocator &locator) const;
43 
45  void WriteBestBlock(CDBBatch &batch, const CBlockLocator &locator);
46  };
47 
48 private:
52  std::atomic<bool> m_synced{false};
53 
55  std::atomic<const CBlockIndex *> m_best_block_index{nullptr};
56 
57  std::thread m_thread_sync;
59 
65  void ThreadSync();
66 
77  bool Commit();
78 
79 protected:
81 
82  void BlockConnected(const std::shared_ptr<const CBlock> &block,
83  const CBlockIndex *pindex) override;
84 
85  void ChainStateFlushed(const CBlockLocator &locator) override;
86 
87  const CBlockIndex *CurrentIndex() { return m_best_block_index.load(); };
88 
90  [[nodiscard]] virtual bool Init();
91 
93  virtual bool WriteBlock(const CBlock &block, const CBlockIndex *pindex) {
94  return true;
95  }
96 
99  virtual bool CommitInternal(CDBBatch &batch);
100 
103  virtual bool Rewind(const CBlockIndex *current_tip,
104  const CBlockIndex *new_tip);
105 
106  virtual DB &GetDB() const = 0;
107 
109  virtual const char *GetName() const = 0;
110 
111 public:
113  virtual ~BaseIndex();
114 
120  bool BlockUntilSyncedToCurrentChain() const LOCKS_EXCLUDED(::cs_main);
121 
122  void Interrupt();
123 
126  [[nodiscard]] bool Start(Chainstate &active_chainstate);
127 
129  void Stop();
130 
132  IndexSummary GetSummary() const;
133 };
134 
135 #endif // BITCOIN_INDEX_BASE_H
The database stores a block locator of the chain the database is synced to so that the TxIndex can ef...
Definition: base.h:36
void WriteBestBlock(CDBBatch &batch, const CBlockLocator &locator)
Write block locator of the chain that the index is in sync with.
Definition: base.cpp:48
DB(const fs::path &path, size_t n_cache_size, bool f_memory=false, bool f_wipe=false, bool f_obfuscate=false)
Definition: base.cpp:36
bool ReadBestBlock(CBlockLocator &locator) const
Read block locator of the chain that the index is in sync with.
Definition: base.cpp:40
Base class for indices of blockchain data.
Definition: base.h:27
void Stop()
Stops the instance from staying in sync with blockchain updates.
Definition: base.cpp:379
virtual bool Init()
Initialize internal state from the database and block index.
Definition: base.cpp:58
void BlockConnected(const std::shared_ptr< const CBlock > &block, const CBlockIndex *pindex) override
Notifies listeners of a block being connected.
Definition: base.cpp:248
bool Start(Chainstate &active_chainstate)
Start initializes the sync state and registers the instance as a ValidationInterface so that it stays...
Definition: base.cpp:365
virtual ~BaseIndex()
Destructor interrupts sync thread if running and blocks until it exits.
Definition: base.cpp:53
std::atomic< const CBlockIndex * > m_best_block_index
The last block in the chain that the index is in sync with.
Definition: base.h:55
virtual bool CommitInternal(CDBBatch &batch)
Virtual method called internally by Commit that can be overridden to atomically commit more index sta...
Definition: base.cpp:217
std::atomic< bool > m_synced
Whether the index is in sync with the main chain.
Definition: base.h:52
CThreadInterrupt m_interrupt
Definition: base.h:58
IndexSummary GetSummary() const
Get a summary of the index and its state.
Definition: base.cpp:387
const CBlockIndex * CurrentIndex()
Definition: base.h:87
void ChainStateFlushed(const CBlockLocator &locator) override
Notifies listeners of the new active block chain on-disk.
Definition: base.cpp:295
std::thread m_thread_sync
Definition: base.h:57
bool Commit()
Write the current index state (eg.
Definition: base.cpp:208
virtual bool WriteBlock(const CBlock &block, const CBlockIndex *pindex)
Write update index entries for a newly connected block.
Definition: base.h:93
void ThreadSync()
Sync the index with the block index starting from the current best block.
Definition: base.cpp:133
virtual DB & GetDB() const =0
Chainstate * m_chainstate
Definition: base.h:80
virtual bool Rewind(const CBlockIndex *current_tip, const CBlockIndex *new_tip)
Rewind index to an earlier chain tip during a chain reorg.
Definition: base.cpp:228
virtual const char * GetName() const =0
Get the name of the index for display in logs.
Definition: block.h:60
The block chain is a tree shaped structure starting with the genesis block at the root,...
Definition: blockindex.h:26
Batch of changes queued to be written to a CDBWrapper.
Definition: dbwrapper.h:54
A helper class for interruptible sleeps.
Implement this to subscribe to events generated in validation.
Chainstate stores and provides an API to update our local knowledge of the current best chain.
Definition: validation.h:648
Path class wrapper to block calls to the fs::path(std::string) implicit constructor and the fs::path:...
Definition: fs.h:30
RecursiveMutex cs_main
Mutex to guard access to validation specific variables, such as reading or changing the chainstate.
Definition: cs_main.cpp:7
void Interrupt(NodeContext &node)
Interrupt threads.
Definition: init.cpp:192
Describes a place in the block chain to another node such that if the other node doesn't have the sam...
Definition: block.h:105
std::string name
Definition: base.h:17
bool synced
Definition: base.h:18
int best_block_height
Definition: base.h:19
#define LOCKS_EXCLUDED(...)
Definition: threadsafety.h:55