From 6851107b3a52ec869e5e3a2cb4eb02d6c743b8e5 Mon Sep 17 00:00:00 2001 From: Pieter Wuille Date: Mon, 15 Feb 2016 05:13:27 +0100 Subject: BIP9 Implementation Inspired by former implementations by Eric Lombrozo and Rusty Russell, and based on code by Jorge Timon. --- src/versionbits.cpp | 133 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 133 insertions(+) create mode 100644 src/versionbits.cpp (limited to 'src/versionbits.cpp') diff --git a/src/versionbits.cpp b/src/versionbits.cpp new file mode 100644 index 000000000..fbb60c0fc --- /dev/null +++ b/src/versionbits.cpp @@ -0,0 +1,133 @@ +// 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. + +#include "versionbits.h" + +ThresholdState AbstractThresholdConditionChecker::GetStateFor(const CBlockIndex* pindexPrev, const Consensus::Params& params, ThresholdConditionCache& cache) const +{ + int nPeriod = Period(params); + int nThreshold = Threshold(params); + int64_t nTimeStart = BeginTime(params); + int64_t nTimeTimeout = EndTime(params); + + // 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 != NULL) { + pindexPrev = pindexPrev->GetAncestor(pindexPrev->nHeight - ((pindexPrev->nHeight + 1) % nPeriod)); + } + + // Walk backwards in steps of nPeriod to find a pindexPrev whose information is known + std::vector vToCompute; + while (cache.count(pindexPrev) == 0) { + if (pindexPrev == NULL) { + // The genesis block is by definition defined. + cache[pindexPrev] = THRESHOLD_DEFINED; + break; + } + if (pindexPrev->GetMedianTimePast() < nTimeStart) { + // Optimizaton: don't recompute down further, as we know every earlier block will be before the start time + cache[pindexPrev] = THRESHOLD_DEFINED; + break; + } + vToCompute.push_back(pindexPrev); + pindexPrev = pindexPrev->GetAncestor(pindexPrev->nHeight - nPeriod); + } + + // At this point, cache[pindexPrev] is known + assert(cache.count(pindexPrev)); + ThresholdState state = cache[pindexPrev]; + + // Now walk forward and compute the state of descendants of pindexPrev + while (!vToCompute.empty()) { + ThresholdState stateNext = state; + pindexPrev = vToCompute.back(); + vToCompute.pop_back(); + + switch (state) { + case THRESHOLD_DEFINED: { + if (pindexPrev->GetMedianTimePast() >= nTimeTimeout) { + stateNext = THRESHOLD_FAILED; + } else if (pindexPrev->GetMedianTimePast() >= nTimeStart) { + stateNext = THRESHOLD_STARTED; + } + break; + } + case THRESHOLD_STARTED: { + if (pindexPrev->GetMedianTimePast() >= nTimeTimeout) { + stateNext = THRESHOLD_FAILED; + break; + } + // We need to count + const CBlockIndex* pindexCount = pindexPrev; + int count = 0; + for (int i = 0; i < nPeriod; i++) { + if (Condition(pindexCount, params)) { + count++; + } + pindexCount = pindexCount->pprev; + } + if (count >= nThreshold) { + stateNext = THRESHOLD_LOCKED_IN; + } + break; + } + case THRESHOLD_LOCKED_IN: { + // Always progresses into ACTIVE. + stateNext = THRESHOLD_ACTIVE; + break; + } + case THRESHOLD_FAILED: + case THRESHOLD_ACTIVE: { + // Nothing happens, these are terminal states. + break; + } + } + cache[pindexPrev] = state = stateNext; + } + + return state; +} + +namespace +{ +/** + * Class to implement versionbits logic. + */ +class VersionBitsConditionChecker : public AbstractThresholdConditionChecker { +private: + const Consensus::DeploymentPos id; + +protected: + int64_t BeginTime(const Consensus::Params& params) const { return params.vDeployments[id].nStartTime; } + int64_t EndTime(const Consensus::Params& params) const { return params.vDeployments[id].nTimeout; } + int Period(const Consensus::Params& params) const { return params.nMinerConfirmationWindow; } + int Threshold(const Consensus::Params& params) const { return params.nRuleChangeActivationThreshold; } + + bool Condition(const CBlockIndex* pindex, const Consensus::Params& params) const + { + return (((pindex->nVersion & VERSIONBITS_TOP_MASK) == VERSIONBITS_TOP_BITS) && (pindex->nVersion & Mask(params)) != 0); + } + +public: + VersionBitsConditionChecker(Consensus::DeploymentPos id_) : id(id_) {} + uint32_t Mask(const Consensus::Params& params) const { return ((uint32_t)1) << params.vDeployments[id].bit; } +}; + +} + +ThresholdState VersionBitsState(const CBlockIndex* pindexPrev, const Consensus::Params& params, Consensus::DeploymentPos pos, VersionBitsCache& cache) +{ + return VersionBitsConditionChecker(pos).GetStateFor(pindexPrev, params, cache.caches[pos]); +} + +uint32_t VersionBitsMask(const Consensus::Params& params, Consensus::DeploymentPos pos) +{ + return VersionBitsConditionChecker(pos).Mask(params); +} + +void VersionBitsCache::Clear() +{ + for (unsigned int d = 0; d < Consensus::MAX_VERSION_BITS_DEPLOYMENTS; d++) { + caches[d].clear(); + } +} -- cgit v1.2.3 From a22bde94497a634bf750d0bdd4fd3227ba169d21 Mon Sep 17 00:00:00 2001 From: paveljanik Date: Fri, 1 Apr 2016 21:31:48 +0200 Subject: Fix typo: Optimizaton -> Optimization --- src/versionbits.cpp | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'src/versionbits.cpp') diff --git a/src/versionbits.cpp b/src/versionbits.cpp index fbb60c0fc..78feb8ab0 100644 --- a/src/versionbits.cpp +++ b/src/versionbits.cpp @@ -25,7 +25,7 @@ ThresholdState AbstractThresholdConditionChecker::GetStateFor(const CBlockIndex* break; } if (pindexPrev->GetMedianTimePast() < nTimeStart) { - // Optimizaton: don't recompute down further, as we know every earlier block will be before the start time + // Optimization: don't recompute down further, as we know every earlier block will be before the start time cache[pindexPrev] = THRESHOLD_DEFINED; break; } -- cgit v1.2.3 From d3df40e51a29bd98830043dd19829126390d1bc4 Mon Sep 17 00:00:00 2001 From: Luke Dashjr Date: Sat, 23 Apr 2016 23:30:20 +0000 Subject: Implement BIP 9 GBT changes - BIP9DeploymentInfo struct for static deployment info - VersionBitsDeploymentInfo: Avoid C++11ism by commenting parameter names - getblocktemplate: Make sure to set deployments in the version if it is LOCKED_IN - In this commit, all rules are considered required for clients to support --- src/versionbits.cpp | 11 +++++++++++ 1 file changed, 11 insertions(+) (limited to 'src/versionbits.cpp') diff --git a/src/versionbits.cpp b/src/versionbits.cpp index fbb60c0fc..041ca2adb 100644 --- a/src/versionbits.cpp +++ b/src/versionbits.cpp @@ -4,6 +4,17 @@ #include "versionbits.h" +#include "consensus/params.h" + +const struct BIP9DeploymentInfo VersionBitsDeploymentInfo[Consensus::MAX_VERSION_BITS_DEPLOYMENTS] = { + { + /*.name =*/ "testdummy", + }, + { + /*.name =*/ "csv", + } +}; + ThresholdState AbstractThresholdConditionChecker::GetStateFor(const CBlockIndex* pindexPrev, const Consensus::Params& params, ThresholdConditionCache& cache) const { int nPeriod = Period(params); -- cgit v1.2.3 From 98790608a43e60b8025346034d28ff1f58cebab0 Mon Sep 17 00:00:00 2001 From: Luke Dashjr Date: Wed, 1 Jun 2016 16:47:36 +0000 Subject: getblocktemplate: Explicitly handle the distinction between GBT-affecting softforks vs not --- src/versionbits.cpp | 2 ++ 1 file changed, 2 insertions(+) (limited to 'src/versionbits.cpp') diff --git a/src/versionbits.cpp b/src/versionbits.cpp index 041ca2adb..c06c9907b 100644 --- a/src/versionbits.cpp +++ b/src/versionbits.cpp @@ -9,9 +9,11 @@ const struct BIP9DeploymentInfo VersionBitsDeploymentInfo[Consensus::MAX_VERSION_BITS_DEPLOYMENTS] = { { /*.name =*/ "testdummy", + /*.gbt_force =*/ true, }, { /*.name =*/ "csv", + /*.gbt_force =*/ true, } }; -- cgit v1.2.3 From 8b49040854be2e26b66366aeae1cba4716f93d93 Mon Sep 17 00:00:00 2001 From: Pieter Wuille Date: Fri, 6 Nov 2015 01:42:38 +0100 Subject: BIP141: Commitment structure and deployment Includes a fix by Suhas Daftuar and LongShao007 --- src/versionbits.cpp | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'src/versionbits.cpp') diff --git a/src/versionbits.cpp b/src/versionbits.cpp index 043819c65..bf32ae662 100644 --- a/src/versionbits.cpp +++ b/src/versionbits.cpp @@ -14,6 +14,10 @@ const struct BIP9DeploymentInfo VersionBitsDeploymentInfo[Consensus::MAX_VERSION { /*.name =*/ "csv", /*.gbt_force =*/ true, + }, + { + /*.name =*/ "segwit", + /*.gbt_force =*/ false, } }; -- cgit v1.2.3 From fc146095d20452686efe1944b143452bec394343 Mon Sep 17 00:00:00 2001 From: mruddy Date: Fri, 6 May 2016 22:08:39 +0000 Subject: RPC: augment getblockchaininfo bip9_softforks data --- src/versionbits.cpp | 35 +++++++++++++++++++++++++++++++++++ 1 file changed, 35 insertions(+) (limited to 'src/versionbits.cpp') diff --git a/src/versionbits.cpp b/src/versionbits.cpp index bf32ae662..d73f34051 100644 --- a/src/versionbits.cpp +++ b/src/versionbits.cpp @@ -105,6 +105,36 @@ ThresholdState AbstractThresholdConditionChecker::GetStateFor(const CBlockIndex* return state; } +int AbstractThresholdConditionChecker::GetStateSinceHeightFor(const CBlockIndex* pindexPrev, const Consensus::Params& params, ThresholdConditionCache& cache) const +{ + const ThresholdState initialState = GetStateFor(pindexPrev, params, cache); + + // BIP 9 about state DEFINED: "The genesis block is by definition in this state for each deployment." + if (initialState == THRESHOLD_DEFINED) { + return 0; + } + + const int nPeriod = Period(params); + + // 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. + // To ease understanding of the following height calculation, it helps to remember that + // right now pindexPrev points to the block prior to the block that we are computing for, thus: + // if we are computing for the last block of a period, then pindexPrev points to the second to last block of the period, and + // if we are computing for the first block of a period, then pindexPrev points to the last block of the previous period. + // The parent of the genesis block is represented by NULL. + pindexPrev = pindexPrev->GetAncestor(pindexPrev->nHeight - ((pindexPrev->nHeight + 1) % nPeriod)); + + const CBlockIndex* previousPeriodParent = pindexPrev->GetAncestor(pindexPrev->nHeight - nPeriod); + + while (previousPeriodParent != NULL && GetStateFor(previousPeriodParent, params, cache) == initialState) { + pindexPrev = previousPeriodParent; + previousPeriodParent = pindexPrev->GetAncestor(pindexPrev->nHeight - nPeriod); + } + + // Adjust the result because right now we point to the parent block. + return pindexPrev->nHeight + 1; +} + namespace { /** @@ -137,6 +167,11 @@ ThresholdState VersionBitsState(const CBlockIndex* pindexPrev, const Consensus:: return VersionBitsConditionChecker(pos).GetStateFor(pindexPrev, params, cache.caches[pos]); } +int VersionBitsStateSinceHeight(const CBlockIndex* pindexPrev, const Consensus::Params& params, Consensus::DeploymentPos pos, VersionBitsCache& cache) +{ + return VersionBitsConditionChecker(pos).GetStateSinceHeightFor(pindexPrev, params, cache.caches[pos]); +} + uint32_t VersionBitsMask(const Consensus::Params& params, Consensus::DeploymentPos pos) { return VersionBitsConditionChecker(pos).Mask(params); -- cgit v1.2.3 From 569596cc5148ef868350a9720013d38faf3e34ce Mon Sep 17 00:00:00 2001 From: Suhas Daftuar Date: Wed, 8 Mar 2017 15:56:59 -0500 Subject: Don't require segwit in getblocktemplate for segwit signalling or mining Segwit's version bit will be signalled for all invocations of CreateNewBlock, and not specifying segwit only will cause CreateNewBlock to skip transactions with witness from being selected. Github-Pull: #9955 Rebased-From: abe7b3d3abe10e3554b770f40824174b3b217490 --- src/versionbits.cpp | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'src/versionbits.cpp') diff --git a/src/versionbits.cpp b/src/versionbits.cpp index d73f34051..8a7cce748 100644 --- a/src/versionbits.cpp +++ b/src/versionbits.cpp @@ -17,7 +17,7 @@ const struct BIP9DeploymentInfo VersionBitsDeploymentInfo[Consensus::MAX_VERSION }, { /*.name =*/ "segwit", - /*.gbt_force =*/ false, + /*.gbt_force =*/ true, } }; -- cgit v1.2.3