big-bang: single chain (#446)

1 files changed, 0 insertions, 162 deletions

diff --git a/core/consensus-timestamp.go b/core/consensus-timestamp.go
deleted file mode 100644
index d7ce8e2..0000000
--- a/core/consensus-timestamp.go
+++ /dev/null
@@ -1,162 +0,0 @@
-// Copyright 2018 The dexon-consensus Authors
-// This file is part of the dexon-consensus library.
-//
-// The dexon-consensus library is free software: you can redistribute it
-// and/or modify it under the terms of the GNU Lesser General Public License as
-// published by the Free Software Foundation, either version 3 of the License,
-// or (at your option) any later version.
-//
-// The dexon-consensus library is distributed in the hope that it will be
-// useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser
-// General Public License for more details.
-//
-// You should have received a copy of the GNU Lesser General Public License
-// along with the dexon-consensus library. If not, see
-// <http://www.gnu.org/licenses/>.
-
-package core
-
-import (
-	"errors"
-	"time"
-
-	"github.com/dexon-foundation/dexon-consensus/core/types"
-)
-
-// consensusTimestamp calculates a block's finalization timestamp. Notice that
-// the Finalization timestamps are increasing (but not strictly increasing).
-// Instance functions:
-// - processBlocks(blocks []*types.Block) error
-//   called with blocks output from total ordering
-// - appendConfig(round uint64, config *types.Config) error
-//   called when a new config is known
-// - synced() bool
-//   called in sync mode
-type consensusTimestamp struct {
-	timestampsOfChains []time.Time
-
-	// Stores number of chains for rounds.
-	numChainsOfRounds []uint32
-	numChainsBase     uint64
-
-	// dMoment represents the genesis time.
-	dMoment time.Time
-
-	// lastTimestamp is the previous assigned consensus timestamp.
-	lastTimestamp time.Time
-}
-
-var (
-	// ErrTimestampNotIncrease for timestamp is not strictly increasing on one
-	// chain.
-	ErrTimestampNotIncrease = errors.New("timestamp is not increasing")
-	// ErrNoRoundConfig for no round config found.
-	ErrNoRoundConfig = errors.New("no round config found")
-	// ErrConsensusTimestampRewind for rewinding timestamp.
-	ErrConsensusTimestampRewind = errors.New("consensus timestamp rewind")
-)
-
-// newConsensusTimestamp creates consensus timestamp instance.
-func newConsensusTimestamp(
-	dMoment time.Time, round uint64, numChains uint32) *consensusTimestamp {
-
-	ts := make([]time.Time, numChains)
-	for i := range ts {
-		ts[i] = dMoment
-	}
-	return &consensusTimestamp{
-		numChainsOfRounds:  []uint32{numChains},
-		numChainsBase:      round,
-		dMoment:            dMoment,
-		timestampsOfChains: ts,
-	}
-}
-
-// appendConfig appends a configuration for upcoming round. When you append
-// a config for round R, next time you can only append the config for round R+1.
-func (ct *consensusTimestamp) appendConfig(
-	round uint64, config *types.Config) error {
-	if round != uint64(len(ct.numChainsOfRounds))+ct.numChainsBase {
-		return ErrRoundNotIncreasing
-	}
-	// This segment is to handle the corner case for config checking logic in
-	// processBlock method.
-	if len(ct.numChainsOfRounds) == 1 {
-		if ct.numChainsOfRounds[0] > config.NumChains {
-			ct.resizeTimetamps(ct.numChainsOfRounds[0])
-		} else {
-			ct.resizeTimetamps(config.NumChains)
-		}
-	}
-	ct.numChainsOfRounds = append(ct.numChainsOfRounds, config.NumChains)
-	return nil
-}
-
-func (ct *consensusTimestamp) resizeTimetamps(numChain uint32) {
-	l := uint32(len(ct.timestampsOfChains))
-	if numChain > l {
-		for i := l; i < numChain; i++ {
-			ct.timestampsOfChains = append(ct.timestampsOfChains, ct.dMoment)
-		}
-	} else if numChain < l {
-		ct.timestampsOfChains = ct.timestampsOfChains[:numChain]
-	}
-}
-
-// ProcessBlocks is the entry function.
-func (ct *consensusTimestamp) processBlocks(blocks []*types.Block) (err error) {
-	for _, block := range blocks {
-		// Rounds might interleave within rounds if no configuration change
-		// occurs. And it is limited to one round, that is, round r can only
-		// interleave with r-1 and r+1.
-		round := block.Position.Round
-		if ct.numChainsBase == round || ct.numChainsBase+1 == round {
-			// Normal case, no need to modify timestampsOfChains.
-		} else if ct.numChainsBase+2 == round {
-			// Resize timestampsOfChains if block from r+2 comes, because the interleave
-			// of rounds must be less than 1. Resize the size to
-			// max(numChainsOfRounds[r+1], numChainsOfRounds[r+2]).
-			if len(ct.numChainsOfRounds) < 2 {
-				return ErrNoRoundConfig
-			}
-			ct.numChainsBase++
-			ct.numChainsOfRounds = ct.numChainsOfRounds[1:]
-			if ct.numChainsOfRounds[0] > ct.numChainsOfRounds[1] {
-				ct.resizeTimetamps(ct.numChainsOfRounds[0])
-			} else {
-				ct.resizeTimetamps(ct.numChainsOfRounds[1])
-			}
-		} else {
-			// Error if round < base or round > base + 2.
-			return ErrInvalidRoundID
-		}
-		ts := ct.timestampsOfChains[:ct.numChainsOfRounds[round-ct.numChainsBase]]
-		if block.Finalization.Timestamp, err = getMedianTime(ts); err != nil {
-			return
-		}
-		if block.Timestamp.Before(ct.timestampsOfChains[block.Position.ChainID]) {
-			return ErrTimestampNotIncrease
-		}
-		ct.timestampsOfChains[block.Position.ChainID] = block.Timestamp
-		// If the finalization timestamp is before the last timestamp, set it to
-		// the last one. Notice that the finalization timestamps are increasing but
-		// not strictly increasing.
-		if block.Finalization.Timestamp.Before(ct.lastTimestamp) {
-			block.Finalization.Timestamp = ct.lastTimestamp
-		} else {
-			ct.lastTimestamp = block.Finalization.Timestamp
-		}
-	}
-	return
-}
-
-func (ct *consensusTimestamp) isSynced() bool {
-	numChain := ct.numChainsOfRounds[0]
-	for i := uint32(0); i < numChain; i++ {
-		if ct.timestampsOfChains[i].Equal(ct.dMoment) {
-			return false
-		}
-	}
-	return true
-}