From 248fdaa5ccca535ddce93173f2f0f3bc60b9381d Mon Sep 17 00:00:00 2001 From: Wei-Ning Huang Date: Fri, 2 Nov 2018 12:04:20 +0800 Subject: Rename import due to dexon-consensus rename --- .../dexon-consensus/core/negative-ack.go | 211 +++++++++++++++++++++ 1 file changed, 211 insertions(+) create mode 100644 vendor/github.com/dexon-foundation/dexon-consensus/core/negative-ack.go (limited to 'vendor/github.com/dexon-foundation/dexon-consensus/core/negative-ack.go') diff --git a/vendor/github.com/dexon-foundation/dexon-consensus/core/negative-ack.go b/vendor/github.com/dexon-foundation/dexon-consensus/core/negative-ack.go new file mode 100644 index 000000000..417862912 --- /dev/null +++ b/vendor/github.com/dexon-foundation/dexon-consensus/core/negative-ack.go @@ -0,0 +1,211 @@ +// 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 +// . + +package core + +import ( + "time" + + "github.com/dexon-foundation/dexon-consensus/core/types" +) + +type negativeAck struct { + // owner is the ID of proposer itself, this is used when deciding + // a node to be restricted or not. + owner types.NodeID + + numOfNodes int + + // timeDelay and timeExpire are for nack timeout. + timeDelay time.Duration + timeExpire time.Duration + + // restricteds stores nodes which has been restricted and the time it's + // restricted. + restricteds map[types.NodeID]time.Time + + // lastVotes and lockedVotes store the votes for nack. lastVotes[nid1][nid2] + // and lockedVotes[nid1][nid2] both mean that nid2 votes nid1. The difference + // is lockedVotes works only when nid1 is restricted, so that the votes are + // needed to be locked. + lastVotes map[types.NodeID]map[types.NodeID]struct{} + lockedVotes map[types.NodeID]map[types.NodeID]struct{} + + // timeDiffs is the cache for last time stamps. timeDiffs[nid1][nid2] means + // the last updated timestamps nid1 sees nid2. + timeDiffs map[types.NodeID]map[types.NodeID]map[types.NodeID]time.Time +} + +// newNegativeAck creates a new negaticeAck instance. +func newNegativeAck(nid types.NodeID) *negativeAck { + n := &negativeAck{ + owner: nid, + numOfNodes: 0, + restricteds: make(map[types.NodeID]time.Time), + lastVotes: make(map[types.NodeID]map[types.NodeID]struct{}), + lockedVotes: make(map[types.NodeID]map[types.NodeID]struct{}), + timeDiffs: make(map[types.NodeID]map[types.NodeID]map[types.NodeID]time.Time), + } + n.addNode(nid) + return n +} + +// processNewVote is called when a new "vote" occurs, that is, a node +// sees that other 2f + 1 nodes think a node is slow. "nid" is the +// node which propesed the block which the timestamps votes and "h" is +// the node been voted to be nacked. +func (n *negativeAck) processNewVote( + nid types.NodeID, + h types.NodeID, +) []types.NodeID { + + nackeds := []types.NodeID{} + if _, exist := n.restricteds[h]; exist { + n.lockedVotes[h][nid] = struct{}{} + if len(n.lockedVotes[h]) > 2*(n.numOfNodes-1)/3 { + nackeds = append(nackeds, h) + delete(n.restricteds, h) + } + } else { + if n.owner == nid { + n.restrict(h) + } else { + n.lastVotes[h][nid] = struct{}{} + if len(n.lastVotes[h]) > (n.numOfNodes-1)/3 { + n.restrict(h) + } + } + } + return nackeds +} + +// processTimestamps process new timestamps of a block which is proposed by +// node nid, and returns the nodes being nacked. +func (n *negativeAck) processTimestamps( + nid types.NodeID, + ts map[types.NodeID]time.Time, +) []types.NodeID { + + n.checkRestrictExpire() + + nackeds := []types.NodeID{} + for h := range n.timeDiffs { + if n.timeDiffs[nid][h][h].Equal(ts[h]) { + votes := 0 + for hh := range n.timeDiffs { + if ts[hh].Sub(n.timeDiffs[nid][h][hh]) >= n.timeDelay { + votes++ + } + } + if votes > 2*((n.numOfNodes-1)/3) { + n.lastVotes[h][nid] = struct{}{} + nack := n.processNewVote(nid, h) + for _, i := range nack { + nackeds = append(nackeds, i) + } + } else { + delete(n.lastVotes[h], nid) + } + } else { + for hh := range n.timeDiffs { + n.timeDiffs[nid][h][hh] = ts[hh] + } + delete(n.lastVotes[h], nid) + } + } + return nackeds +} + +func (n *negativeAck) checkRestrictExpire() { + expired := []types.NodeID{} + now := time.Now() + for h, t := range n.restricteds { + if now.Sub(t) >= n.timeExpire { + expired = append(expired, h) + } + } + for _, h := range expired { + delete(n.restricteds, h) + } +} + +func (n *negativeAck) restrict(nid types.NodeID) { + if _, exist := n.restricteds[nid]; !exist { + n.restricteds[nid] = time.Now().UTC() + n.lockedVotes[nid] = map[types.NodeID]struct{}{} + for h := range n.lastVotes[nid] { + n.lockedVotes[nid][h] = struct{}{} + } + } +} + +func (n *negativeAck) getRestrictedNodes() map[types.NodeID]struct{} { + n.checkRestrictExpire() + ret := map[types.NodeID]struct{}{} + for h := range n.restricteds { + ret[h] = struct{}{} + } + return ret +} + +func (n *negativeAck) setTimeDelay(t time.Duration) { + n.timeDelay = t +} + +func (n *negativeAck) setTimeExpire(t time.Duration) { + n.timeExpire = t +} + +func (n *negativeAck) addNode(nid types.NodeID) { + n.numOfNodes++ + n.lastVotes[nid] = make(map[types.NodeID]struct{}) + n.lockedVotes[nid] = make(map[types.NodeID]struct{}) + + newTimeDiff := make(map[types.NodeID]map[types.NodeID]time.Time) + for h := range n.timeDiffs { + newTimeDiff2 := make(map[types.NodeID]time.Time) + for hh := range n.timeDiffs { + newTimeDiff2[hh] = time.Time{} + } + newTimeDiff[h] = newTimeDiff2 + } + n.timeDiffs[nid] = newTimeDiff + for h := range n.timeDiffs { + n.timeDiffs[h][nid] = make(map[types.NodeID]time.Time) + } +} + +func (n *negativeAck) deleteNode(nid types.NodeID) { + n.numOfNodes-- + + delete(n.timeDiffs, nid) + + for h := range n.lastVotes { + delete(n.lastVotes[h], nid) + } + delete(n.lastVotes, nid) + delete(n.lockedVotes, nid) + + for h := range n.timeDiffs { + delete(n.timeDiffs[h], nid) + for hh := range n.timeDiffs[h] { + delete(n.timeDiffs[h][hh], nid) + } + } + + delete(n.restricteds, nid) +} -- cgit