Draft of consensus/reactor refactor.

binary/int.go

@@ -158,8 +158,7 @@ func ReadUint64(r io.Reader, n *int64, err *error) uint64 {
 
 // Varint
 
-func uvarintSize(i_ uint) int {
-	i := uint64(i_)
+func uvarintSize(i uint64) int {
 	if i == 0 {
 		return 0
 	}
@@ -193,7 +192,7 @@ func WriteVarint(i int, w io.Writer, n *int64, err *error) {
 		negate = true
 		i = -i
 	}
-	var size = uvarintSize(uint(i))
+	var size = uvarintSize(uint64(i))
 	if negate {
 		// e.g. 0xF1 for a single negative byte
 		WriteUint8(uint8(size+0xF0), w, n, err)
@@ -236,7 +235,7 @@ func ReadVarint(r io.Reader, n *int64, err *error) int {
 // Uvarint
 
 func WriteUvarint(i uint, w io.Writer, n *int64, err *error) {
-	var size = uvarintSize(i)
+	var size = uvarintSize(uint64(i))
 	WriteUint8(uint8(size), w, n, err)
 	if size > 0 {
 		buf := make([]byte, 8)

blockchain/store.go

@@ -101,9 +101,8 @@ func (bs *BlockStore) LoadBlockMeta(height uint) *types.BlockMeta {
 	return meta
 }
 
-// NOTE: the Precommit-vote heights are for the block at `height-1`
-// Since these are included in the subsequent block, the height
-// is off by 1.
+// The +2/3 and other Precommit-votes for block at `height`.
+// This Validation comes from block.LastValidation for `height+1`.
 func (bs *BlockStore) LoadBlockValidation(height uint) *types.Validation {
 	var n int64
 	var err error
@@ -158,8 +157,8 @@ func (bs *BlockStore) SaveBlock(block *types.Block, blockParts *types.PartSet, s
 	}
 
 	// Save block validation (duplicate and separate from the Block)
-	blockValidationBytes := binary.BinaryBytes(block.Validation)
-	bs.db.Set(calcBlockValidationKey(height), blockValidationBytes)
+	blockValidationBytes := binary.BinaryBytes(block.LastValidation)
+	bs.db.Set(calcBlockValidationKey(height-1), blockValidationBytes)
 
 	// Save seen validation (seen +2/3 precommits for block)
 	seenValidationBytes := binary.BinaryBytes(seenValidation)

consensus/reactor.go

@@ -49,8 +49,8 @@ type ConsensusReactor struct {
 
 func NewConsensusReactor(consensusState *ConsensusState, blockStore *bc.BlockStore, sync bool) *ConsensusReactor {
 	conR := &ConsensusReactor{
-		blockStore: blockStore,
 		quit:       make(chan struct{}),
+		blockStore: blockStore,
 		conS:       consensusState,
 		sync:       sync,
 	}
@@ -119,7 +119,7 @@ func (conR *ConsensusReactor) AddPeer(peer *p2p.Peer) {
 	go conR.gossipVotesRoutine(peer, peerState)
 
 	// Send our state to peer.
-	conR.sendNewRoundStep(peer)
+	conR.sendNewRoundStepMessage(peer)
 }
 
 // Implements Reactor
@@ -164,18 +164,13 @@ func (conR *ConsensusReactor) Receive(chId byte, peer *p2p.Peer, msgBytes []byte
 		case *ProposalMessage:
 			ps.SetHasProposal(msg.Proposal)
 			err = conR.conS.SetProposal(msg.Proposal)
-
 		case *PartMessage:
 			if msg.Type == partTypeProposalBlock {
 				ps.SetHasProposalBlockPart(msg.Height, msg.Round, msg.Part.Proof.Index)
 				_, err = conR.conS.AddProposalBlockPart(msg.Height, msg.Round, msg.Part)
-			} else if msg.Type == partTypeProposalPOL {
-				ps.SetHasProposalPOLPart(msg.Height, msg.Round, msg.Part.Proof.Index)
-				_, err = conR.conS.AddProposalPOLPart(msg.Height, msg.Round, msg.Part)
 			} else {
 				log.Warn(Fmt("Unknown part type %v", msg.Type))
 			}
-
 		default:
 			log.Warn(Fmt("Unknown message type %v", reflect.TypeOf(msg)))
 		}
@@ -186,15 +181,14 @@ func (conR *ConsensusReactor) Receive(chId byte, peer *p2p.Peer, msgBytes []byte
 			vote := msg.Vote
 			if rs.Height != vote.Height {
 				if rs.Height == vote.Height+1 {
-					if rs.Step == RoundStepNewHeight && vote.Type == types.VoteTypeCommit {
+					if rs.Step == RoundStepNewHeight && vote.Type == types.VoteTypePrecommit {
 						goto VOTE_PASS // *ducks*
 					}
 				}
 				return // Wrong height. Not necessarily a bad peer.
 			}
 		VOTE_PASS:
-			validatorIndex := msg.ValidatorIndex
-			address, _ := rs.Validators.GetByIndex(validatorIndex)
+			address, _ := rs.Validators.GetByIndex(msg.ValidatorIndex)
 			added, index, err := conR.conS.AddVote(address, vote)
 			if err != nil {
 				// If conflicting sig, broadcast evidence tx for slashing. Else punish peer.
@@ -213,8 +207,8 @@ func (conR *ConsensusReactor) Receive(chId byte, peer *p2p.Peer, msgBytes []byte
 					// TODO: punish peer
 				}
 			}
-			// Initialize Prevotes/Precommits/Commits if needed
-			ps.EnsureVoteBitArrays(rs.Height, rs.Validators.Size())
+			// Initialize Prevotes/Precommits if needed
+			ps.EnsureVoteBitArrays(rs.Height, rs.Validators.Size(), _)
 			ps.SetHasVote(vote, index)
 			if added {
 				msg := &HasVoteMessage{
@@ -247,7 +241,6 @@ func (conR *ConsensusReactor) SetPrivValidator(priv *sm.PrivValidator) {
 // reset the state, turn off fast sync, start the consensus-state-machine
 func (conR *ConsensusReactor) SwitchToConsensus(state *sm.State) {
 	conR.conS.updateToState(state, false)
-	conR.conS.newStepCh <- conR.conS.getRoundState()
 	conR.sync = false
 	conR.conS.Start()
 }
@@ -270,6 +263,7 @@ func makeRoundStepMessages(rs *RoundState) (nrsMsg *NewRoundStepMessage, csMsg *
 		Round:  rs.Round,
 		Step:   rs.Step,
 		SecondsSinceStartTime: uint(timeElapsed.Seconds()),
+		LastCommitRound:       rs.LastCommit.Round(),
 	}
 
 	// If the step is commit, then also broadcast a CommitStepMessage.
@@ -306,7 +300,7 @@ func (conR *ConsensusReactor) broadcastNewRoundStepRoutine() {
 	}
 }
 
-func (conR *ConsensusReactor) sendNewRoundStep(peer *p2p.Peer) {
+func (conR *ConsensusReactor) sendNewRoundStepMessage(peer *p2p.Peer) {
 	rs := conR.conS.GetRoundState()
 	nrsMsg, csMsg := makeRoundStepMessages(rs)
 	if nrsMsg != nil {
@@ -330,8 +324,6 @@ OUTER_LOOP:
 		prs := ps.GetRoundState()
 
 		// Send proposal Block parts?
-		// NOTE: if we or peer is at RoundStepCommit*, the round
-		// won't necessarily match, but that's OK.
 		if rs.ProposalBlockParts.HasHeader(prs.ProposalBlockParts) {
 			//log.Debug("ProposalBlockParts matched", "blockParts", prs.ProposalBlockParts)
 			if index, ok := rs.ProposalBlockParts.BitArray().Sub(prs.ProposalBlockBitArray.Copy()).PickRandom(); ok {
@@ -400,21 +392,6 @@ OUTER_LOOP:
 			continue OUTER_LOOP
 		}
 
-		// Send proposal POL parts?
-		if rs.ProposalPOLParts.HasHeader(prs.ProposalPOLParts) {
-			if index, ok := rs.ProposalPOLParts.BitArray().Sub(prs.ProposalPOLBitArray.Copy()).PickRandom(); ok {
-				msg := &PartMessage{
-					Height: rs.Height,
-					Round:  rs.Round,
-					Type:   partTypeProposalPOL,
-					Part:   rs.ProposalPOLParts.GetPart(index),
-				}
-				peer.Send(DataChannel, msg)
-				ps.SetHasProposalPOLPart(rs.Height, rs.Round, index)
-				continue OUTER_LOOP
-			}
-		}
-
 		// Nothing to do. Sleep.
 		time.Sleep(peerGossipSleepDuration)
 		continue OUTER_LOOP
@@ -443,18 +420,23 @@ OUTER_LOOP:
 			sleeping = 0
 		}
 
+		// prsVoteSet: a pointer to a VoteSet field of prs.
 		// Returns true when useful work was done.
-		trySendVote := func(height uint, voteSet *VoteSet, peerVoteSet *BitArray) (sent bool) {
+		trySendVote := func(voteSet *VoteSet, prsVoteSet **BitArray) (sent bool) {
 			if voteSet == nil {
 				return false
-			} else if peerVoteSet == nil {
-				ps.EnsureVoteBitArrays(height, voteSet.Size())
-				return true
+			}
+			if *prsVoteSet == nil {
+				ps.EnsureVoteBitArrays(voteSet.Height(), voteSet.Size(), prs)
+				// We could return true here (useful work was done)
+				// or, we can continue since prsVoteSet is no longer nil.
+				if *prsVoteSet == nil {
+					panic("prsVoteSet should not be nil after ps.EnsureVoteBitArrays")
+				}
 			}
 			// TODO: give priority to our vote.
-			if index, ok := voteSet.BitArray().Sub(peerVoteSet.Copy()).PickRandom(); ok {
+			if index, ok := voteSet.BitArray().Sub((*prsVoteSet).Copy()).PickRandom(); ok {
 				vote := voteSet.GetByIndex(index)
-				// NOTE: vote may be a commit.
 				msg := &VoteMessage{index, vote}
 				peer.Send(VoteChannel, msg)
 				ps.SetHasVote(vote, index)
@@ -463,103 +445,95 @@ OUTER_LOOP:
 			return false
 		}
 
+		// prsVoteSet: a pointer to a VoteSet field of prs.
 		// Returns true when useful work was done.
-		trySendCommitFromValidation := func(blockMeta *types.BlockMeta, validation *types.Validation, peerVoteSet *BitArray) (sent bool) {
+		trySendPrecommitFromValidation := func(validation *types.Validation, prsVoteSet **BitArray) (sent bool) {
 			if validation == nil {
 				return false
-			} else if peerVoteSet == nil {
-				ps.EnsureVoteBitArrays(blockMeta.Header.Height, uint(len(validation.Commits)))
-				return true
-			}
-			if index, ok := validation.BitArray().Sub(prs.Commits.Copy()).PickRandom(); ok {
-				commit := validation.Commits[index]
-				log.Debug("Picked commit to send", "index", index, "commit", commit)
-				// Reconstruct vote.
-				vote := &types.Vote{
-					Height:     prs.Height,
-					Round:      commit.Round,
-					Type:       types.VoteTypeCommit,
-					BlockHash:  blockMeta.Hash,
-					BlockParts: blockMeta.Parts,
-					Signature:  commit.Signature,
+			} else if *prsVoteSet == nil {
+				ps.EnsureVoteBitArrays(validation.Height(), uint(len(validation.Precommits)), prs)
+				// We could return true here (useful work was done)
+				// or, we can continue since prsVoteSet is no longer nil.
+				if *prsVoteSet == nil {
+					panic("prsVoteSet should not be nil after ps.EnsureVoteBitArrays")
 				}
-				msg := &VoteMessage{index, vote}
+			}
+			if index, ok := validation.BitArray().Sub((*prsVoteSet).Copy()).PickRandom(); ok {
+				precommit := validation.Precommits[index]
+				log.Debug("Picked precommit to send", "index", index, "precommit", precommit)
+				msg := &VoteMessage{index, precommit}
 				peer.Send(VoteChannel, msg)
-				ps.SetHasVote(vote, index)
+				ps.SetHasVote(precommit, index)
 				return true
 			}
 			return false
 		}
 
-		// If height matches, then send LastCommits, Prevotes, Precommits, or Commits.
+		// If height matches, then send LastCommit, Prevotes, Precommits.
 		if rs.Height == prs.Height {
-
-			// If there are lastcommits to send...
-			if prs.Round == 0 && prs.Step == RoundStepNewHeight {
-				if trySendVote(rs.Height-1, rs.LastCommits, prs.LastCommits) {
+			// If there are lastCommits to send...
+			if prs.Step == RoundStepNewHeight {
+				if trySendVote(rs.LastCommit, prs.LastCommit) {
 					continue OUTER_LOOP
 				}
 			}
-
 			// If there are prevotes to send...
 			if rs.Round == prs.Round && prs.Step <= RoundStepPrevote {
-				if trySendVote(rs.Height, rs.Prevotes, prs.Prevotes) {
+				if trySendVote(rs.Prevotes, prs.Prevotes) {
 					continue OUTER_LOOP
 				}
 			}
-
 			// If there are precommits to send...
 			if rs.Round == prs.Round && prs.Step <= RoundStepPrecommit {
-				if trySendVote(rs.Height, rs.Precommits, prs.Precommits) {
+				if trySendVote(rs.Precommits, prs.Precommits) {
 					continue OUTER_LOOP
 				}
 			}
-
-			// If there are any commits to send...
-			if trySendVote(rs.Height, rs.Commits, prs.Commits) {
-				continue OUTER_LOOP
-			}
 		}
 
-		// Catchup logic
-		if prs.Height != 0 && !prs.HasAllCatchupCommits {
-
-			// If peer is lagging by height 1
-			if rs.Height == prs.Height+1 {
-				if rs.LastCommits.Size() > 0 {
-					// Sync peer to rs.LastCommits
-					if trySendVote(prs.Height, rs.LastCommits, prs.Commits) {
-						continue OUTER_LOOP
-					} else {
-						ps.SetHasAllCatchupCommits(prs.Height)
-					}
+		// Special catchup logic.
+		// If peer is lagging by height 1, send LastCommit.
+		if prs.Height != 0 && prs.Height == rs.Height-1 {
+			if prs.Round == rs.LastCommit.Round() {
+				if trySendVote(rs.LastCommit, prs.Precommits) {
+					continue OUTER_LOOP
+					// XXX CONTONUE
 				}
-			}
-
-			// If peer is lagging by more than 1, send Validation.
-			if rs.Height >= prs.Height+2 {
-				// Load the blockMeta for block at prs.Height
-				blockMeta := conR.blockStore.LoadBlockMeta(prs.Height)
-				// Load the block validation for prs.Height+1,
-				// which contains commit signatures for prs.Height.
-				validation := conR.blockStore.LoadBlockValidation(prs.Height + 1)
-				log.Debug("Loaded BlockValidation for catch-up", "height", prs.Height+1, "blockMeta", blockMeta, "validation", validation)
-
-				if trySendCommitFromValidation(blockMeta, validation, prs.Commits) {
+			} else {
+				ps.SetCatchupCommitRound(prs.Height, rs.LastCommit.Round())
+				ps.EnsureVoteBitArrays(prs.Height, rs.LastCommit.Size(), prs)
+				if trySendVote(rs.LastCommit, prs.CatchupCommit) {
 					continue OUTER_LOOP
-				} else {
-					ps.SetHasAllCatchupCommits(prs.Height)
 				}
 			}
 		}
 
+		// Catchup logic
+		// If peer is lagging by more than 1, send Validation.
+		if prs.Height != 0 && prs.Height <= rs.Height-2 {
+			// Load the block validation for prs.Height,
+			// which contains precommit signatures for prs.Height.
+			validation := conR.blockStore.LoadBlockValidation(prs.Height)
+			log.Debug("Loaded BlockValidation for catch-up", "height", prs.Height, "validation", validation)
+			// Peer's CommitRound should be -1 or equal to the validation's precommit rounds.
+			// If not, warn.
+			if prs.CommitRound == -1 {
+				ps.SetCommitRound(prs.Height, validation.Round())
+				continue OUTER_LOOP // Get prs := ps.GetRoundState() again.
+			} else if prs.CommitRound != validation.Round() {
+				log.Warn("Peer's CommitRound during catchup not equal to commit round",
+					"height", prs.Height, "validation", validation, "prs.CommitRound", prs.CommitRound)
+			} else if trySendPrecommitFromValidation(validation, prs.Commit) {
+				continue OUTER_LOOP
+			}
+		}
+
 		if sleeping == 0 {
 			// We sent nothing. Sleep...
 			sleeping = 1
 			log.Debug("No votes to send, sleeping", "peer", peer,
 				"localPV", rs.Prevotes.BitArray(), "peerPV", prs.Prevotes,
-				"localPC", rs.Precommits.BitArray(), "peerPC", prs.Precommits,
-				"localCM", rs.Commits.BitArray(), "peerCM", prs.Commits)
+				"localPC", rs.Precommits.BitArray(), "peerPC", prs.Precommits)
 		} else if sleeping == 2 {
 			// Continued sleep...
 			sleeping = 1
@@ -585,9 +559,13 @@ type PeerRoundState struct {
 	ProposalPOLBitArray   *BitArray           // True bit -> has part
 	Prevotes              *BitArray           // All votes peer has for this round
 	Precommits            *BitArray           // All precommits peer has for this round
-	Commits               *BitArray           // All commits peer has for this height
-	LastCommits           *BitArray           // All commits peer has for last height
-	HasAllCatchupCommits  bool                // Used for catch-up
+	LastCommitRound       uint                // Round of commit for last height.
+	LastCommit            *BitArray           // All commit precommits of commit for last height.
+
+	// If peer is leading in height, the round that peer believes commit round is.
+	// If peer is lagging in height, the round that we believe commit round is.
+	CatchupCommitRound int
+	CatchupCommit      *BitArray // All commit precommits peer has for this height
 }
 
 //-----------------------------------------------------------------------------
@@ -658,7 +636,8 @@ func (ps *PeerState) SetHasProposalPOLPart(height uint, round uint, index uint)
 	ps.ProposalPOLBitArray.SetIndex(uint(index), true)
 }
 
-func (ps *PeerState) EnsureVoteBitArrays(height uint, numValidators uint) {
+// prs: If given, will also update this PeerRoundState copy.
+func (ps *PeerState) EnsureVoteBitArrays(height uint, numValidators uint, prs *PeerRoundState) {
 	ps.mtx.Lock()
 	defer ps.mtx.Unlock()
 
@@ -669,14 +648,22 @@ func (ps *PeerState) EnsureVoteBitArrays(height uint, numValidators uint) {
 		if ps.Precommits == nil {
 			ps.Precommits = NewBitArray(numValidators)
 		}
-		if ps.Commits == nil {
-			ps.Commits = NewBitArray(numValidators)
+		if ps.CatchupCommit == nil {
+			ps.CatchupCommit = NewBitArray(numValidators)
 		}
 	} else if ps.Height == height+1 {
-		if ps.LastCommits == nil {
-			ps.LastCommits = NewBitArray(numValidators)
+		if ps.LastCommit == nil {
+			ps.LastCommit = NewBitArray(numValidators)
 		}
 	}
+
+	// Also, update prs if given.
+	if prs != nil {
+		prs.Prevotes = ps.Prevotes
+		prs.Precommits = ps.Precommits
+		prs.LastCommit = ps.LastCommit
+		prs.CatchupCommit = ps.CatchupCommit
+	}
 }
 
 func (ps *PeerState) SetHasVote(vote *types.Vote, index uint) {
@@ -687,10 +674,10 @@ func (ps *PeerState) SetHasVote(vote *types.Vote, index uint) {
 }
 
 func (ps *PeerState) setHasVote(height uint, round uint, type_ byte, index uint) {
-	if ps.Height == height+1 && type_ == types.VoteTypeCommit {
-		// Special case for LastCommits.
-		ps.LastCommits.SetIndex(index, true)
-		log.Debug("SetHasVote", "lastCommits", ps.LastCommits, "index", index)
+	if ps.Height == height+1 && ps.LastCommitRound == round && type_ == types.VoteTypePrecommit {
+		// Special case for LastCommit.
+		ps.LastCommit.SetIndex(index, true)
+		log.Debug("setHasVote", "LastCommit", ps.LastCommit, "index", index)
 		return
 	} else if ps.Height != height {
 		// Does not apply.
@@ -702,29 +689,33 @@ func (ps *PeerState) setHasVote(height uint, round uint, type_ byte, index uint)
 		ps.Prevotes.SetIndex(index, true)
 		log.Debug("SetHasVote", "peer", ps.Key, "prevotes", ps.Prevotes, "index", index)
 	case types.VoteTypePrecommit:
+		if ps.CommitRound == round {
+			ps.Commit.SetIndex(index, true)
+		}
 		ps.Precommits.SetIndex(index, true)
 		log.Debug("SetHasVote", "peer", ps.Key, "precommits", ps.Precommits, "index", index)
-	case types.VoteTypeCommit:
-		if round < ps.Round {
-			ps.Prevotes.SetIndex(index, true)
-			ps.Precommits.SetIndex(index, true)
-		}
-		ps.Commits.SetIndex(index, true)
-		log.Debug("SetHasVote", "peer", ps.Key, "commits", ps.Commits, "index", index)
 	default:
 		panic("Invalid vote type")
 	}
 }
 
-// When catching up, this helps keep track of whether
-// we should send more commit votes from the block (validation) store
-func (ps *PeerState) SetHasAllCatchupCommits(height uint) {
+func (ps *PeerState) SetCatchupCommitRound(height, round uint) {
 	ps.mtx.Lock()
 	defer ps.mtx.Unlock()
 
-	if ps.Height == height {
-		ps.HasAllCatchupCommits = true
+	if ps.Height != height {
+		return
+	}
+	if ps.CatchupCommitRound != -1 && ps.CatchupCommitRound != round {
+		log.Warn("Conflicting CatchupCommitRound",
+			"height", height,
+			"orig", ps.CatchupCommitRound,
+			"new", round,
+		)
+		// TODO think harder
 	}
+	ps.CatchupCommitRound = round
+	ps.CatchupCommit = nil
 }
 
 func (ps *PeerState) ApplyNewRoundStepMessage(msg *NewRoundStepMessage, rs *RoundState) {
@@ -735,6 +726,8 @@ func (ps *PeerState) ApplyNewRoundStepMessage(msg *NewRoundStepMessage, rs *Roun
 	psHeight := ps.Height
 	psRound := ps.Round
 	//psStep := ps.Step
+	psCatchupCommitRound := ps.CatchupCommitRound
+	psCatchupCommit := ps.CatchupCommitRound
 
 	startTime := time.Now().Add(-1 * time.Duration(msg.SecondsSinceStartTime) * time.Second)
 	ps.Height = msg.Height
@@ -751,16 +744,22 @@ func (ps *PeerState) ApplyNewRoundStepMessage(msg *NewRoundStepMessage, rs *Roun
 		ps.Prevotes = nil
 		ps.Precommits = nil
 	}
+	if psHeight == msg.Height && psRound != msg.Round && msg.Round == psCatchupCommitRound {
+		// Peer caught up to CatchupCommitRound.
+		ps.Precommits = psCatchupCommit
+	}
 	if psHeight != msg.Height {
-		// Shift Commits to LastCommits
-		if psHeight+1 == msg.Height {
-			ps.LastCommits = ps.Commits
+		// Shift Precommits to LastCommit.
+		if psHeight+1 == msg.Height && psRound == msg.LastCommitRound {
+			ps.LastCommitRound = msg.LastCommitRound
+			ps.LastCommit = ps.Precommits
 		} else {
-			ps.LastCommits = nil
+			ps.LastCommitRound = msg.LastCommitRound
+			ps.LastCommit = nil
 		}
 		// We'll update the BitArray capacity later.
-		ps.Commits = nil
-		ps.HasAllCatchupCommits = false
+		ps.CatchupCommitRound = -1
+		ps.CatchupCommit = nil
 	}
 }
 
@@ -780,11 +779,7 @@ func (ps *PeerState) ApplyHasVoteMessage(msg *HasVoteMessage) {
 	ps.mtx.Lock()
 	defer ps.mtx.Unlock()
 
-	// Special case for LastCommits
-	if ps.Height == msg.Height+1 && msg.Type == types.VoteTypeCommit {
-		ps.LastCommits.SetIndex(msg.Index, true)
-		return
-	} else if ps.Height != msg.Height {
+	if ps.Height != msg.Height {
 		return
 	}
 
@@ -826,15 +821,18 @@ func DecodeMessage(bz []byte) (msgType byte, msg ConsensusMessage, err error) {
 
 //-------------------------------------
 
+// For every height/round/step transition
 type NewRoundStepMessage struct {
 	Height                uint
 	Round                 uint
 	Step                  RoundStepType
 	SecondsSinceStartTime uint
+	LastCommitRound       uint
 }
 
 func (m *NewRoundStepMessage) String() string {
-	return fmt.Sprintf("[NewRoundStep H:%v R:%v S:%v]", m.Height, m.Round, m.Step)
+	return fmt.Sprintf("[NewRoundStep H:%v R:%v S:%v LCR:%v]",
+		m.Height, m.Round, m.Step, m.LastCommitRound)
 }
 
 //-------------------------------------

consensus/state.go

@@ -56,7 +56,7 @@ Consensus State Machine Overview:
 
 * NewHeight:
   * Upon entering NewHeight,
-    * Move Precommits to LastPrecommits and increment height.
+    * Move Precommits to LastCommit and increment height.
     * Wait until `CommitTime+timeoutCommit` to receive straggler commits. --> Then, goto NewRound round 0
 
 * Proof of Safety:
@@ -184,7 +184,7 @@ type RoundState struct {
 	LockedBlock        *types.Block
 	LockedBlockParts   *types.PartSet
 	Votes              *HeightVoteSet
-	LastPrecommits     *VoteSet // Last precommits for Height-1
+	LastCommit         *VoteSet // Last precommits for Height-1
 }
 
 func (rs *RoundState) String() string {
@@ -201,7 +201,7 @@ func (rs *RoundState) StringIndented(indent string) string {
 %s  ProposalBlock: %v %v
 %s  LockedBlock:   %v %v
 %s  Votes:         %v
-%s  LastPrecommits: %v
+%s  LastCommit: %v
 %s}`,
 		indent, rs.Height, rs.Round, rs.Step,
 		indent, rs.StartTime,
@@ -211,7 +211,7 @@ func (rs *RoundState) StringIndented(indent string) string {
 		indent, rs.ProposalBlockParts.StringShort(), rs.ProposalBlock.StringShort(),
 		indent, rs.LockedBlockParts.StringShort(), rs.LockedBlock.StringShort(),
 		indent, rs.Votes.StringIndented(indent+"    "),
-		indent, rs.LastPrecommits.StringShort(),
+		indent, rs.LastCommit.StringShort(),
 		indent)
 }
 
@@ -252,13 +252,13 @@ func NewConsensusState(state *sm.State, blockStore *bc.BlockStore, mempoolReacto
 	}
 	cs.updateToState(state, true)
 	cs.maybeRebond()
-	cs.reconstructLastPrecommits(state)
+	cs.reconstructLastCommit(state)
 	return cs
 }
 
-// Reconstruct LastPrecommits from SeenValidation, which we saved along with the block,
+// Reconstruct LastCommit from SeenValidation, which we saved along with the block,
 // (which happens even before saving the state)
-func (cs *ConsensusState) reconstructLastPrecommits(state *sm.State) {
+func (cs *ConsensusState) reconstructLastCommit(state *sm.State) {
 	if state.LastBlockHeight == 0 {
 		return
 	}
@@ -275,13 +275,13 @@ func (cs *ConsensusState) reconstructLastPrecommits(state *sm.State) {
 		}
 		added, _, err := lastPrecommits.AddByIndex(uint(idx), precommitVote)
 		if !added || err != nil {
-			panic(Fmt("Failed to reconstruct LastPrecommits: %v", err))
+			panic(Fmt("Failed to reconstruct LastCommit: %v", err))
 		}
 	}
 	if !lastPrecommits.HasTwoThirdsMajority() {
-		panic("Failed to reconstruct LastPrecommits: Does not have +2/3 maj")
+		panic("Failed to reconstruct LastCommit: Does not have +2/3 maj")
 	}
-	cs.LastPrecommits = lastPrecommits
+	cs.LastCommit = lastPrecommits
 }
 
 func (cs *ConsensusState) GetState() *sm.State {
@@ -373,11 +373,14 @@ func (cs *ConsensusState) updateToState(state *sm.State, contiguous bool) {
 	cs.LockedBlock = nil
 	cs.LockedBlockParts = nil
 	cs.Votes = NewHeightVoteSet(height, validators)
-	cs.LastPrecommits = lastPrecommits
+	cs.LastCommit = lastPrecommits
 
 	cs.state = state
 	cs.stagedBlock = nil
 	cs.stagedState = nil
+
+	// Finally, broadcast RoundState
+	cs.newStepCh <- cs.getRoundState()
 }
 
 // If we're unbonded, broadcast RebondTx.
@@ -528,11 +531,11 @@ func (cs *ConsensusState) createProposalBlock() (*types.Block, *types.PartSet) {
 	var validation *types.Validation
 	if cs.Height == 1 {
 		// We're creating a proposal for the first block.
-		// The validation is empty.
+		// The validation is empty, but not nil.
 		validation = &types.Validation{}
-	} else if cs.LastPrecommits.HasTwoThirdsMajority() {
-		// Make the validation from LastPrecommits
-		validation = cs.LastPrecommits.MakeValidation()
+	} else if cs.LastCommit.HasTwoThirdsMajority() {
+		// Make the validation from LastCommit
+		validation = cs.LastCommit.MakeValidation()
 	} else {
 		// This shouldn't happen.
 		log.Error("EnterPropose: Cannot propose anything: No validation for the previous block.")
@@ -871,7 +874,6 @@ func (cs *ConsensusState) FinalizeCommit(height uint) {
 	// * cs.Height has been increment to height+1
 	// * cs.Step is now RoundStepNewHeight
 	// * cs.StartTime is set to when we should start round0.
-	cs.newStepCh <- cs.getRoundState()
 	// Start round 0 when cs.StartTime.
 	go cs.scheduleRound0(height)
 	return
@@ -954,9 +956,9 @@ func (cs *ConsensusState) AddVote(address []byte, vote *types.Vote) (added bool,
 func (cs *ConsensusState) addVote(address []byte, vote *types.Vote) (added bool, index uint, err error) {
 	// A precommit for the previous height?
 	if vote.Height+1 == cs.Height && vote.Type == types.VoteTypePrecommit {
-		added, index, err = cs.LastPrecommits.AddByAddress(address, vote)
+		added, index, err = cs.LastCommit.AddByAddress(address, vote)
 		if added {
-			log.Debug(Fmt("Added to lastPrecommits: %v", cs.LastPrecommits.StringShort()))
+			log.Debug(Fmt("Added to lastPrecommits: %v", cs.LastCommit.StringShort()))
 		}
 		return
 	}

consensus/vote_set.go

@@ -59,6 +59,14 @@ func (voteSet *VoteSet) Height() uint {
 	}
 }
 
+func (voteSet *VoteSet) Round() uint {
+	if voteSet == nil {
+		return 0
+	} else {
+		return voteSet.round
+	}
+}
+
 func (voteSet *VoteSet) Size() uint {
 	if voteSet == nil {
 		return 0
@@ -206,36 +214,6 @@ func (voteSet *VoteSet) TwoThirdsMajority() (hash []byte, parts types.PartSetHea
 	}
 }
 
-func (voteSet *VoteSet) MakeValidation() *types.Validation {
-	if voteSet.type_ != types.VoteTypePrecommit {
-		panic("Cannot MakeValidation() unless VoteSet.Type is types.VoteTypePrecommit")
-	}
-	voteSet.mtx.Lock()
-	defer voteSet.mtx.Unlock()
-	if len(voteSet.maj23Hash) == 0 {
-		panic("Cannot MakeValidation() unless a blockhash has +2/3")
-	}
-	precommits := make([]types.Precommit, voteSet.valSet.Size())
-	voteSet.valSet.Iterate(func(valIndex uint, val *sm.Validator) bool {
-		vote := voteSet.votes[valIndex]
-		if vote == nil {
-			return false
-		}
-		if !bytes.Equal(vote.BlockHash, voteSet.maj23Hash) {
-			return false
-		}
-		if !vote.BlockParts.Equals(voteSet.maj23Parts) {
-			return false
-		}
-		precommits[valIndex] = types.Precommit{val.Address, vote.Signature}
-		return false
-	})
-	return &types.Validation{
-		Round:      voteSet.round,
-		Precommits: precommits,
-	}
-}
-
 func (voteSet *VoteSet) String() string {
 	return voteSet.StringIndented("")
 }
@@ -269,3 +247,56 @@ func (voteSet *VoteSet) StringShort() string {
 	return fmt.Sprintf(`VoteSet{H:%v R:%v T:%v +2/3:%v %v}`,
 		voteSet.height, voteSet.round, voteSet.type_, voteSet.maj23Exists, voteSet.votesBitArray)
 }
+
+//--------------------------------------------------------------------------------
+// Validation
+
+func (voteSet *VoteSet) MakeValidation() *types.Validation {
+	if voteSet.type_ != types.VoteTypePrecommit {
+		panic("Cannot MakeValidation() unless VoteSet.Type is types.VoteTypePrecommit")
+	}
+	voteSet.mtx.Lock()
+	defer voteSet.mtx.Unlock()
+	if len(voteSet.maj23Hash) == 0 {
+		panic("Cannot MakeValidation() unless a blockhash has +2/3")
+	}
+	precommits := make([]types.Precommit, voteSet.valSet.Size())
+	voteSet.valSet.Iterate(func(valIndex uint, val *sm.Validator) bool {
+		vote := voteSet.votes[valIndex]
+		if vote == nil {
+			return false
+		}
+		if !bytes.Equal(vote.BlockHash, voteSet.maj23Hash) {
+			return false
+		}
+		if !vote.BlockParts.Equals(voteSet.maj23Parts) {
+			return false
+		}
+		precommits[valIndex] = types.Precommit{val.Address, vote.Signature}
+		return false
+	})
+	return &types.Validation{
+		Round:      voteSet.round,
+		Precommits: precommits,
+	}
+}
+
+// XXX
+func VoteSetFromValidation(validation *types.Validation) *VoteSet {
+	lastPrecommits := NewVoteSet(state.LastBlockHeight, 0, types.VoteTypePrecommit, state.LastBondedValidators)
+	seenValidation := cs.blockStore.LoadSeenValidation(state.LastBlockHeight)
+	for idx, precommit := range seenValidation.Precommits {
+		precommitVote := &types.Vote{
+			Height:     state.LastBlockHeight,
+			Round:      seenValidation.Round,
+			Type:       types.VoteTypePrecommit,
+			BlockHash:  state.LastBlockHash,
+			BlockParts: state.LastBlockParts,
+			Signature:  precommit.Signature,
+		}
+		added, _, err := lastPrecommits.AddByIndex(uint(idx), precommitVote)
+		if !added || err != nil {
+			panic(Fmt("Failed to reconstruct LastPrecommits: %v", err))
+		}
+	}
+}

types/block.go

@@ -15,9 +15,9 @@ import (
 )
 
 type Block struct {
-	*Header     `json:"header"`
-	*Validation `json:"validation"`
-	*Data       `json:"data"`
+	*Header        `json:"header"`
+	*Data          `json:"data"`
+	LastValidation *Validation `json:"last_validation"`
 }
 
 // Basic validation that doesn't involve state data.
@@ -46,7 +46,7 @@ func (b *Block) ValidateBasic(chainID string, lastBlockHeight uint, lastBlockHas
 		}
 	*/
 	if b.Header.Height != 1 {
-		if err := b.Validation.ValidateBasic(); err != nil {
+		if err := b.LastValidation.ValidateBasic(); err != nil {
 			return err
 		}
 	}
@@ -58,12 +58,12 @@ func (b *Block) ValidateBasic(chainID string, lastBlockHeight uint, lastBlockHas
 // If the block is incomplete (e.g. missing Header.StateHash)
 // then the hash is nil, to prevent the usage of that hash.
 func (b *Block) Hash() []byte {
-	if b.Header == nil || b.Validation == nil || b.Data == nil {
+	if b.Header == nil || b.Data == nil || b.LastValidation == nil {
 		return nil
 	}
 	hashHeader := b.Header.Hash()
-	hashValidation := b.Validation.Hash()
 	hashData := b.Data.Hash()
+	hashLastValidation := b.LastValidation.Hash()
 
 	// If hashHeader is nil, required fields are missing.
 	if len(hashHeader) == 0 {
@@ -71,7 +71,7 @@ func (b *Block) Hash() []byte {
 	}
 
 	// Merkle hash from subhashes.
-	hashes := [][]byte{hashHeader, hashValidation, hashData}
+	hashes := [][]byte{hashHeader, hashData, hashLastValidation}
 	return merkle.SimpleHashFromHashes(hashes)
 }
 
@@ -106,8 +106,8 @@ func (b *Block) StringIndented(indent string) string {
 %s  %v
 %s}#%X`,
 		indent, b.Header.StringIndented(indent+"  "),
-		indent, b.Validation.StringIndented(indent+"  "),
 		indent, b.Data.StringIndented(indent+"  "),
+		indent, b.LastValidation.StringIndented(indent+"  "),
 		indent, b.Hash())
 }
 
@@ -174,56 +174,39 @@ func (h *Header) StringIndented(indent string) string {
 		indent, h.Hash())
 }
 
-//-----------------------------------------------------------------------------
-
-type Precommit struct {
-	Address   []byte                   `json:"address"`
-	Signature account.SignatureEd25519 `json:"signature"`
-}
-
-func (pc Precommit) IsZero() bool {
-	return pc.Signature.IsZero()
-}
-
-func (pc Precommit) String() string {
-	return fmt.Sprintf("Precommit{A:%X %X}", pc.Address, Fingerprint(pc.Signature))
-}
-
 //-------------------------------------
 
-// NOTE: The Precommits are in order of address to preserve the bonded ValidatorSet order.
-// Any peer with a block can gossip precommits by index with a peer without recalculating the
-// active ValidatorSet.
+// NOTE: Validation is empty for height 1, but never nil.
 type Validation struct {
-	Round      uint        `json:"round"`      // Round for all precommits
-	Precommits []Precommit `json:"precommits"` // Precommits (or nil) of all active validators in address order.
+	// NOTE: The Precommits are in order of address to preserve the bonded ValidatorSet order.
+	// Any peer with a block can gossip precommits by index with a peer without recalculating the
+	// active ValidatorSet.
+	Precommits []*Vote `json:"precommits"`
 
 	// Volatile
 	hash     []byte
 	bitArray *BitArray
 }
 
+func (v *Validation) Height() uint {
+	if len(v.Precommits) == 0 {
+		return 0
+	}
+	return v.Precommits[0].Height
+}
+
+func (v *Validation) Round() uint {
+	if len(v.Precommits) == 0 {
+		return 0
+	}
+	return v.Precommits[0].Round
+}
+
 func (v *Validation) ValidateBasic() error {
 	if len(v.Precommits) == 0 {
 		return errors.New("No precommits in validation")
 	}
-	lastAddress := []byte{}
-	for i := 0; i < len(v.Precommits); i++ {
-		precommit := v.Precommits[i]
-		if precommit.IsZero() {
-			if len(precommit.Address) > 0 {
-				return errors.New("Zero precommits should not have an address")
-			}
-		} else {
-			if len(precommit.Address) == 0 {
-				return errors.New("Nonzero precommits should have an address")
-			}
-			if len(lastAddress) > 0 && bytes.Compare(lastAddress, precommit.Address) != -1 {
-				return errors.New("Invalid precommit order")
-			}
-			lastAddress = precommit.Address
-		}
-	}
+	// TODO Additional validation?
 	return nil
 }
 
@@ -248,10 +231,8 @@ func (v *Validation) StringIndented(indent string) string {
 		precommitStrings[i] = precommit.String()
 	}
 	return fmt.Sprintf(`Validation{
-%s  Round:      %v
 %s  Precommits: %v
 %s}#%X`,
-		indent, v.Round,
 		indent, strings.Join(precommitStrings, "\n"+indent+"  "),
 		indent, v.hash)
 }