dash/src/versionbits.h
UdjinM6 ab8347e06b
Implement dynamic activation thresholds (#3692)
* Implement dynamic activation thresholds

* fix

* Revert unrelated changes

* Clarify switching to/staying in LOCKED_IN state

* Fix signal function to work correctly with num_blocks=0

* Add simplified threshold calculation and use it in tests

* Check that thresholds are decreasing, reach the min level and stay there

* Drop `;`
2020-09-12 17:33:12 +03:00

83 lines
3.3 KiB
C++

// Copyright (c) 2016 The Bitcoin Core developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
#ifndef BITCOIN_VERSIONBITS_H
#define BITCOIN_VERSIONBITS_H
#include <chain.h>
#include <map>
/** What block version to use for new blocks (pre versionbits) */
static const int32_t VERSIONBITS_LAST_OLD_BLOCK_VERSION = 4;
/** What bits to set in version for versionbits blocks */
static const int32_t VERSIONBITS_TOP_BITS = 0x20000000UL;
/** What bitmask determines whether versionbits is in use */
static const int32_t VERSIONBITS_TOP_MASK = 0xE0000000UL;
/** Total bits available for versionbits */
static const int32_t VERSIONBITS_NUM_BITS = 29;
enum class ThresholdState {
DEFINED,
STARTED,
LOCKED_IN,
ACTIVE,
FAILED,
};
// A map that gives the state for blocks whose height is a multiple of Period().
// The map is indexed by the block's parent, however, so all keys in the map
// will either be nullptr or a block with (height + 1) % Period() == 0.
typedef std::map<const CBlockIndex*, ThresholdState> ThresholdConditionCache;
struct VBDeploymentInfo {
/** Deployment name */
const char *name;
/** Whether GBT clients can safely ignore this rule in simplified usage */
bool gbt_force;
/** Whether to check current MN protocol or not */
bool check_mn_protocol;
};
struct BIP9Stats {
int period;
int threshold;
int elapsed;
int count;
bool possible;
};
extern const struct VBDeploymentInfo VersionBitsDeploymentInfo[];
/**
* Abstract class that implements BIP9-style threshold logic, and caches results.
*/
class AbstractThresholdConditionChecker {
protected:
virtual bool Condition(const CBlockIndex* pindex, const Consensus::Params& params) const =0;
virtual int64_t BeginTime(const Consensus::Params& params) const =0;
virtual int64_t EndTime(const Consensus::Params& params) const =0;
virtual int Period(const Consensus::Params& params) const =0;
virtual int Threshold(const Consensus::Params& params, int nAttempt) const =0;
public:
BIP9Stats GetStateStatisticsFor(const CBlockIndex* pindex, const Consensus::Params& params, ThresholdConditionCache& cache) const;
// Note that the functions below take a pindexPrev as input: they compute information for block B based on its parent.
ThresholdState GetStateFor(const CBlockIndex* pindexPrev, const Consensus::Params& params, ThresholdConditionCache& cache) const;
int GetStateSinceHeightFor(const CBlockIndex* pindexPrev, const Consensus::Params& params, ThresholdConditionCache& cache) const;
};
struct VersionBitsCache
{
ThresholdConditionCache caches[Consensus::MAX_VERSION_BITS_DEPLOYMENTS];
void Clear();
};
ThresholdState VersionBitsState(const CBlockIndex* pindexPrev, const Consensus::Params& params, Consensus::DeploymentPos pos, VersionBitsCache& cache);
BIP9Stats VersionBitsStatistics(const CBlockIndex* pindexPrev, const Consensus::Params& params, Consensus::DeploymentPos pos, VersionBitsCache& cache);
int VersionBitsStateSinceHeight(const CBlockIndex* pindexPrev, const Consensus::Params& params, Consensus::DeploymentPos pos, VersionBitsCache& cache);
uint32_t VersionBitsMask(const Consensus::Params& params, Consensus::DeploymentPos pos);
#endif // BITCOIN_VERSIONBITS_H