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-rw-r--r--vendor/github.com/dexon-foundation/dexon-consensus/core/consensus-timestamp.go162
1 files changed, 0 insertions, 162 deletions
diff --git a/vendor/github.com/dexon-foundation/dexon-consensus/core/consensus-timestamp.go b/vendor/github.com/dexon-foundation/dexon-consensus/core/consensus-timestamp.go
deleted file mode 100644
index d7ce8e23e..000000000
--- a/vendor/github.com/dexon-foundation/dexon-consensus/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
-}