Always-active versionbits support

This commit is contained in:
Pieter Wuille 2017-10-11 20:25:05 -07:00
parent 18e071841e
commit d07ee77ab9
2 changed files with 16 additions and 0 deletions

View file

@ -35,6 +35,12 @@ struct BIP9Deployment {
/** Constant for nTimeout very far in the future. */
static constexpr int64_t NO_TIMEOUT = std::numeric_limits<int64_t>::max();
/** Special value for nStartTime indicating that the deployment is always active.
* This is useful for testing, as it means tests don't need to deal with the activation
* process (which takes at least 3 BIP9 intervals). Only tests that specifically test the
* behaviour during activation cannot use this. */
static constexpr int64_t ALWAYS_ACTIVE = -1;
};
/**

View file

@ -27,6 +27,11 @@ ThresholdState AbstractThresholdConditionChecker::GetStateFor(const CBlockIndex*
int64_t nTimeStart = BeginTime(params);
int64_t nTimeTimeout = EndTime(params);
// Check if this deployment is always active.
if (nTimeStart == Consensus::BIP9Deployment::ALWAYS_ACTIVE) {
return THRESHOLD_ACTIVE;
}
// A block's state is always the same as that of the first of its period, so it is computed based on a pindexPrev whose height equals a multiple of nPeriod - 1.
if (pindexPrev != nullptr) {
pindexPrev = pindexPrev->GetAncestor(pindexPrev->nHeight - ((pindexPrev->nHeight + 1) % nPeriod));
@ -136,6 +141,11 @@ BIP9Stats AbstractThresholdConditionChecker::GetStateStatisticsFor(const CBlockI
int AbstractThresholdConditionChecker::GetStateSinceHeightFor(const CBlockIndex* pindexPrev, const Consensus::Params& params, ThresholdConditionCache& cache) const
{
int64_t start_time = BeginTime(params);
if (start_time == Consensus::BIP9Deployment::ALWAYS_ACTIVE) {
return 0;
}
const ThresholdState initialState = GetStateFor(pindexPrev, params, cache);
// BIP 9 about state DEFINED: "The genesis block is by definition in this state for each deployment."