// Enter: +2/3 precomits for block or nil.
// Enter: `timeoutPrevote` after any +2/3 prevotes.
// Enter: any +2/3 precommits for next round.
// Lock & precommit the ProposalBlock if we have enough prevotes for it (a POL in this round)
// else, unlock an existing lock and precommit nil if +2/3 of prevotes were nil,
// else, precommit nil otherwise.
func (cs *ConsensusState) EnterPrecommit(height int, round int, timedOut bool) {
cs.mtx.Lock()
defer cs.mtx.Unlock()
if cs.Height != height || round < cs.Round || (cs.Round == round && RoundStepPrecommit <= cs.Step) {
log.Debug(Fmt("EnterPrecommit(%v/%v): Invalid args. Current step: %v/%v/%v", height, round, cs.Height, cs.Round, cs.Step))
return
}
if timedOut {
cs.evsw.FireEvent(types.EventStringTimeoutWait(), cs.RoundStateEvent())
}
log.Info(Fmt("EnterPrecommit(%v/%v). Current: %v/%v/%v", height, round, cs.Height, cs.Round, cs.Step))
defer func() {
// Done EnterPrecommit:
cs.Round = round
cs.Step = RoundStepPrecommit
cs.newStepCh <- cs.getRoundState()
}()
hash, partsHeader, ok := cs.Votes.Prevotes(round).TwoThirdsMajority()
// If we don't have a polka, we must precommit nil
if !ok {
if cs.LockedBlock != nil {
log.Info("EnterPrecommit: No +2/3 prevotes during EnterPrecommit while we're locked. Precommitting nil")
} else {
log.Info("EnterPrecommit: No +2/3 prevotes during EnterPrecommit. Precommitting nil.")
}
cs.signAddVote(types.VoteTypePrecommit, nil, types.PartSetHeader{})
return
}
// At this point +2/3 prevoted for a particular block or nil
cs.evsw.FireEvent(types.EventStringPolka(), cs.RoundStateEvent())
// the latest POLRound should be this round
if cs.Votes.POLRound() < round {
PanicSanity(Fmt("This POLRound should be %v but got %", round, cs.Votes.POLRound()))
}
// +2/3 prevoted nil. Unlock and precommit nil.
if len(hash) == 0 {
if cs.LockedBlock == nil {
log.Info("EnterPrecommit: +2/3 prevoted for nil.")
} else {
log.Info("EnterPrecommit: +2/3 prevoted for nil. Unlocking")
cs.LockedRound = 0
cs.LockedBlock = nil
cs.LockedBlockParts = nil
cs.evsw.FireEvent(types.EventStringUnlock(), cs.RoundStateEvent())
}
cs.signAddVote(types.VoteTypePrecommit, nil, types.PartSetHeader{})
return
}
// At this point, +2/3 prevoted for a particular block.
// If we're already locked on that block, precommit it, and update the LockedRound
if cs.LockedBlock.HashesTo(hash) {
log.Info("EnterPrecommit: +2/3 prevoted locked block. Relocking")
cs.LockedRound = round
cs.evsw.FireEvent(types.EventStringRelock(), cs.RoundStateEvent())
cs.signAddVote(types.VoteTypePrecommit, hash, partsHeader)
return
}
// If +2/3 prevoted for proposal block, stage and precommit it
if cs.ProposalBlock.HashesTo(hash) {
log.Info("EnterPrecommit: +2/3 prevoted proposal block. Locking", "hash", hash)
// Validate the block.
if err := cs.stageBlock(cs.ProposalBlock, cs.ProposalBlockParts); err != nil {
PanicConsensus(Fmt("EnterPrecommit: +2/3 prevoted for an invalid block: %v", err))
}
cs.LockedRound = round
cs.LockedBlock = cs.ProposalBlock
cs.LockedBlockParts = cs.ProposalBlockParts
cs.evsw.FireEvent(types.EventStringLock(), cs.RoundStateEvent())
cs.signAddVote(types.VoteTypePrecommit, hash, partsHeader)
return
}
// There was a polka in this round for a block we don't have.
// Fetch that block, unlock, and precommit nil.
// The +2/3 prevotes for this round is the POL for our unlock.
// TODO: In the future save the POL prevotes for justification.
cs.LockedRound = 0
cs.LockedBlock = nil
cs.LockedBlockParts = nil
if !cs.ProposalBlockParts.HasHeader(partsHeader) {
cs.ProposalBlock = nil
cs.ProposalBlockParts = types.NewPartSetFromHeader(partsHeader)
}
cs.evsw.FireEvent(types.EventStringUnlock(), cs.RoundStateEvent())
cs.signAddVote(types.VoteTypePrecommit, nil, types.PartSetHeader{})
return
}
func (cs *ConsensusState) addVote(valIndex int, vote *types.Vote, peerKey string) (added bool, address []byte, err error) {
log.Debug("addVote", "voteHeight", vote.Height, "voteType", vote.Type, "csHeight", cs.Height)
defer func() {
if added {
cs.evsw.FireEvent(types.EventStringVote(), &types.EventDataVote{valIndex, address, vote})
}
}()
// A precommit for the previous height?
if vote.Height+1 == cs.Height {
if !(cs.Step == RoundStepNewHeight && vote.Type == types.VoteTypePrecommit) {
// TODO: give the reason ..
// fmt.Errorf("TryAddVote: Wrong height, not a LastCommit straggler commit.")
return added, nil, ErrVoteHeightMismatch
}
added, address, err = cs.LastCommit.AddByIndex(valIndex, vote)
if added {
log.Info(Fmt("Added to lastPrecommits: %v", cs.LastCommit.StringShort()))
}
return
}
// A prevote/precommit for this height?
if vote.Height == cs.Height {
height := cs.Height
added, address, err = cs.Votes.AddByIndex(valIndex, vote, peerKey)
if added {
switch vote.Type {
case types.VoteTypePrevote:
prevotes := cs.Votes.Prevotes(vote.Round)
log.Info(Fmt("Added to prevotes: %v", prevotes.StringShort()))
// First, unlock if prevotes is a valid POL.
// >> lockRound < POLRound <= unlockOrChangeLockRound (see spec)
// NOTE: If (lockRound < POLRound) but !(POLRound <= unlockOrChangeLockRound),
// we'll still EnterNewRound(H,vote.R) and EnterPrecommit(H,vote.R) to process it
// there.
if (cs.LockedBlock != nil) && (cs.LockedRound < vote.Round) && (vote.Round <= cs.Round) {
hash, _, ok := prevotes.TwoThirdsMajority()
if ok && !cs.LockedBlock.HashesTo(hash) {
log.Notice("Unlocking because of POL.", "lockedRound", cs.LockedRound, "POLRound", vote.Round)
cs.LockedRound = 0
cs.LockedBlock = nil
cs.LockedBlockParts = nil
cs.evsw.FireEvent(types.EventStringUnlock(), cs.RoundStateEvent())
}
}
if cs.Round <= vote.Round && prevotes.HasTwoThirdsAny() {
// Round-skip over to PrevoteWait or goto Precommit.
go func() {
cs.EnterNewRound(height, vote.Round, false)
if prevotes.HasTwoThirdsMajority() {
cs.EnterPrecommit(height, vote.Round, false)
} else {
cs.EnterPrevote(height, vote.Round, false)
cs.EnterPrevoteWait(height, vote.Round)
}
}()
} else if cs.Proposal != nil && 0 <= cs.Proposal.POLRound && cs.Proposal.POLRound == vote.Round {
// If the proposal is now complete, enter prevote of cs.Round.
if cs.isProposalComplete() {
go cs.EnterPrevote(height, cs.Round, false)
}
}
case types.VoteTypePrecommit:
precommits := cs.Votes.Precommits(vote.Round)
log.Info(Fmt("Added to precommit: %v", precommits.StringShort()))
hash, _, ok := precommits.TwoThirdsMajority()
if ok {
go func() {
if len(hash) == 0 {
cs.EnterNewRound(height, vote.Round+1, false)
} else {
cs.EnterNewRound(height, vote.Round, false)
cs.EnterPrecommit(height, vote.Round, false)
cs.EnterCommit(height, vote.Round)
}
}()
} else if cs.Round <= vote.Round && precommits.HasTwoThirdsAny() {
go func() {
cs.EnterNewRound(height, vote.Round, false)
cs.EnterPrecommit(height, vote.Round, false)
cs.EnterPrecommitWait(height, vote.Round)
}()
}
default:
PanicSanity(Fmt("Unexpected vote type %X", vote.Type)) // Should not happen.
}
}
// Either duplicate, or error upon cs.Votes.AddByIndex()
return
} else {
err = ErrVoteHeightMismatch
}
// Height mismatch, bad peer?
log.Info("Vote ignored and not added", "voteHeight", vote.Height, "csHeight", cs.Height)
return
}