add mutex to protect the hyperdrive shards

hyperdrive.go

@@ -2,6 +2,7 @@ package hyperdrive
 
 import (
 	"crypto/ecdsa"
+	"sync"
 
 	"github.com/renproject/hyperdrive/block"
 	"github.com/renproject/hyperdrive/process"
@@ -63,6 +64,7 @@ type Hyperdrive interface {
 }
 
 type hyperdrive struct {
+	mu *sync.Mutex
 	replicas map[Shard]Replica
 }
 
@@ -73,13 +75,17 @@ func New(options Options, pStorage ProcessStorage, blockStorage BlockStorage, bl
 		replicas[shard] = replica.New(options, pStorage, blockStorage, blockIterator, validator, observer, broadcaster, shard, privKey)
 	}
 	return &hyperdrive{
+		mu:       new(sync.Mutex),
 		replicas: replicas,
 	}
 }
 
 func (hyper *hyperdrive) Start() {
 	phi.ParForAll(hyper.replicas, func(shard Shard) {
+		hyper.mu.Lock()
 		replica := hyper.replicas[shard]
+		hyper.mu.Unlock()
+
 		replica.Start()
 	})
 }
@@ -92,6 +98,9 @@ func (hyper *hyperdrive) Rebase(sigs Signatories) {
 }
 
 func (hyper *hyperdrive) HandleMessage(message Message) {
+	hyper.mu.Lock()
+	defer hyper.mu.Unlock()
+
 	replica, ok := hyper.replicas[message.Shard]
 	if !ok {
 		return

process/process.go

@@ -304,7 +304,7 @@ func (p *Process) handlePrevote(prevote *Prevote) {
 	if !prevote.blockHash.Equal(block.InvalidHash) {
 		prevoteDebugStr = prevote.blockHash.String()
 	}
-	p.logger.Debugf("received prevote=%v at height=%v and round=%v", prevoteDebugStr, prevote.height, prevote.round)
+	p.logger.Debugf("received prevote= %v at height=%v and round=%v", prevoteDebugStr, prevote.height, prevote.round)
 	n, _, _, firstTimeExceeding2F, firstTimeExceeding2FOnBlockHash := p.state.Prevotes.Insert(prevote)
 	if firstTimeExceeding2F && prevote.Height() == p.state.CurrentHeight && prevote.Round() == p.state.CurrentRound && p.state.CurrentStep == StepPrevote {
 		// upon 2f+1 Prevote{currentHeight, currentRound, *} while step = StepPrevote for the first time