Bitcoin ABC  0.24.7
P2P Digital Currency
versionbits.h
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1 // Copyright (c) 2016-2018 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_VERSIONBITS_H
6 #define BITCOIN_VERSIONBITS_H
7 
8 #include <chain.h>
9 #include <map>
10 
12 static const int32_t VERSIONBITS_LAST_OLD_BLOCK_VERSION = 4;
14 static const int32_t VERSIONBITS_TOP_BITS = 0x20000000UL;
16 static const int32_t VERSIONBITS_TOP_MASK = 0xE0000000UL;
18 static const int32_t VERSIONBITS_NUM_BITS = 29;
19 
26 enum class ThresholdState {
27  DEFINED, // First state that each softfork starts out as. The genesis block
28  // is by definition in this state for each deployment.
29  STARTED, // For blocks past the starttime.
30  LOCKED_IN, // For one retarget period after the first retarget period with
31  // STARTED blocks of which at least threshold have the associated
32  // bit set in nVersion.
33  ACTIVE, // For all blocks after the LOCKED_IN retarget period (final state)
34  FAILED, // For all blocks once the first retarget period after the timeout
35  // time is hit, if LOCKED_IN wasn't already reached (final state)
36 };
37 
38 // A map that gives the state for blocks whose height is a multiple of Period().
39 // The map is indexed by the block's parent, however, so all keys in the map
40 // will either be nullptr or a block with (height + 1) % Period() == 0.
41 typedef std::map<const CBlockIndex *, ThresholdState> ThresholdConditionCache;
42 
44 struct BIP9Stats {
46  int period;
51  int threshold;
55  int elapsed;
60  int count;
65  bool possible;
66 };
67 
73 protected:
74  virtual bool Condition(const CBlockIndex *pindex,
75  const Consensus::Params &params) const = 0;
76  virtual int64_t BeginTime(const Consensus::Params &params) const = 0;
77  virtual int64_t EndTime(const Consensus::Params &params) const = 0;
78  virtual int Period(const Consensus::Params &params) const = 0;
79  virtual int Threshold(const Consensus::Params &params) const = 0;
80 
81 public:
87  const Consensus::Params &params) const;
93  ThresholdState GetStateFor(const CBlockIndex *pindexPrev,
94  const Consensus::Params &params,
95  ThresholdConditionCache &cache) const;
100  int GetStateSinceHeightFor(const CBlockIndex *pindexPrev,
101  const Consensus::Params &params,
102  ThresholdConditionCache &cache) const;
103 };
104 
112 
113  void Clear();
114 };
115 
117  const Consensus::Params &params,
119  VersionBitsCache &cache);
121  const Consensus::Params &params,
123 int VersionBitsStateSinceHeight(const CBlockIndex *pindexPrev,
124  const Consensus::Params &params,
126  VersionBitsCache &cache);
127 uint32_t VersionBitsMask(const Consensus::Params &params,
129 
130 #endif // BITCOIN_VERSIONBITS_H
ThresholdState::STARTED
@ STARTED
VERSIONBITS_TOP_MASK
static const int32_t VERSIONBITS_TOP_MASK
What bitmask determines whether versionbits is in use.
Definition: versionbits.h:16
ThresholdState::ACTIVE
@ ACTIVE
Consensus::DeploymentPos
DeploymentPos
Definition: params.h:16
AbstractThresholdConditionChecker::Threshold
virtual int Threshold(const Consensus::Params &params) const =0
AbstractThresholdConditionChecker::EndTime
virtual int64_t EndTime(const Consensus::Params &params) const =0
VersionBitsCache::Clear
void Clear()
Definition: versionbits.cpp:247
Consensus::MAX_VERSION_BITS_DEPLOYMENTS
@ MAX_VERSION_BITS_DEPLOYMENTS
Definition: params.h:20
AbstractThresholdConditionChecker::GetStateFor
ThresholdState GetStateFor(const CBlockIndex *pindexPrev, const Consensus::Params &params, ThresholdConditionCache &cache) const
Returns the state for pindex A based on parent pindexPrev B.
Definition: versionbits.cpp:8
VERSIONBITS_TOP_BITS
static const int32_t VERSIONBITS_TOP_BITS
What bits to set in version for versionbits blocks.
Definition: versionbits.h:14
VersionBitsCache
BIP 9 allows multiple softforks to be deployed in parallel.
Definition: versionbits.h:110
DisconnectResult::FAILED
@ FAILED
VersionBitsMask
uint32_t VersionBitsMask(const Consensus::Params &params, Consensus::DeploymentPos pos)
Definition: versionbits.cpp:242
AbstractThresholdConditionChecker::Period
virtual int Period(const Consensus::Params &params) const =0
Consensus::Params
Parameters that influence chain consensus.
Definition: params.h:59
VersionBitsStateSinceHeight
int VersionBitsStateSinceHeight(const CBlockIndex *pindexPrev, const Consensus::Params &params, Consensus::DeploymentPos pos, VersionBitsCache &cache)
Definition: versionbits.cpp:234
VersionBitsStatistics
BIP9Stats VersionBitsStatistics(const CBlockIndex *pindexPrev, const Consensus::Params &params, Consensus::DeploymentPos pos)
Definition: versionbits.cpp:227
AbstractThresholdConditionChecker::GetStateSinceHeightFor
int GetStateSinceHeightFor(const CBlockIndex *pindexPrev, const Consensus::Params &params, ThresholdConditionCache &cache) const
Returns the height since when the ThresholdState has started for pindex.
Definition: versionbits.cpp:136
AbstractThresholdConditionChecker::BeginTime
virtual int64_t BeginTime(const Consensus::Params &params) const =0
ThresholdState::DEFINED
@ DEFINED
BIP9Stats::count
int count
Number of blocks with the version bit set since the beginning of the current period.
Definition: versionbits.h:60
BIP9Stats::threshold
int threshold
Number of blocks with the version bit set required to activate the softfork.
Definition: versionbits.h:51
AbstractThresholdConditionChecker
Abstract class that implements BIP9-style threshold logic, and caches results.
Definition: versionbits.h:72
chain.h
AbstractThresholdConditionChecker::GetStateStatisticsFor
BIP9Stats GetStateStatisticsFor(const CBlockIndex *pindex, const Consensus::Params &params) const
Returns the numerical statistics of an in-progress BIP9 softfork in the current period.
Definition: versionbits.cpp:103
BIP9Stats
Display status of an in-progress BIP9 softfork.
Definition: versionbits.h:44
AbstractThresholdConditionChecker::Condition
virtual bool Condition(const CBlockIndex *pindex, const Consensus::Params &params) const =0
VERSIONBITS_NUM_BITS
static const int32_t VERSIONBITS_NUM_BITS
Total bits available for versionbits.
Definition: versionbits.h:18
BIP9Stats::elapsed
int elapsed
Number of blocks elapsed since the beginning of the current period.
Definition: versionbits.h:55
ThresholdState::LOCKED_IN
@ LOCKED_IN
BIP9Stats::possible
bool possible
False if there are not enough blocks left in this period to pass activation threshold.
Definition: versionbits.h:65
VersionBitsState
ThresholdState VersionBitsState(const CBlockIndex *pindexPrev, const Consensus::Params &params, Consensus::DeploymentPos pos, VersionBitsCache &cache)
Definition: versionbits.cpp:219
VERSIONBITS_LAST_OLD_BLOCK_VERSION
static const int32_t VERSIONBITS_LAST_OLD_BLOCK_VERSION
What block version to use for new blocks (pre versionbits)
Definition: versionbits.h:12
ThresholdConditionCache
std::map< const CBlockIndex *, ThresholdState > ThresholdConditionCache
Definition: versionbits.h:41
BIP9Stats::period
int period
Length of blocks of the BIP9 signalling period.
Definition: versionbits.h:46
ThresholdState
ThresholdState
BIP 9 defines a finite-state-machine to deploy a softfork in multiple stages.
Definition: versionbits.h:26
CBlockIndex
The block chain is a tree shaped structure starting with the genesis block at the root,...
Definition: blockindex.h:23
VersionBitsCache::caches
ThresholdConditionCache caches[Consensus::MAX_VERSION_BITS_DEPLOYMENTS]
Definition: versionbits.h:111