1 files changed, 36 insertions, 23 deletions
diff --git a/weed/storage/erasure_coding/ec_volume_info.go b/weed/storage/erasure_coding/ec_volume_info.go
index cefc95173..c26269158 100644
--- a/weed/storage/erasure_coding/ec_volume_info.go
+++ b/weed/storage/erasure_coding/ec_volume_info.go
@@ -1,8 +1,6 @@
 package erasure_coding
 
 import (
-	"fmt"
-
 	"github.com/chrislusf/seaweedfs/weed/pb/master_pb"
 	"github.com/chrislusf/seaweedfs/weed/storage/needle"
 )
@@ -11,59 +9,74 @@ import (
 type EcVolumeInfo struct {
 	VolumeId   needle.VolumeId
 	Collection string
-	shardIds   uint16 // use bits to indicate the shard id
+	ShardBits  ShardBits
 }
 
-func NewEcVolumeInfo(collection string, vid needle.VolumeId) *EcVolumeInfo {
+func NewEcVolumeInfo(collection string, vid needle.VolumeId, shardBits ShardBits) *EcVolumeInfo {
 	return &EcVolumeInfo{
 		Collection: collection,
 		VolumeId:   vid,
+		ShardBits:  shardBits,
 	}
 }
 
 func (ecInfo *EcVolumeInfo) AddShardId(id ShardId) {
-	ecInfo.shardIds |= (1 << id)
+	ecInfo.ShardBits = ecInfo.ShardBits.AddShardId(id)
 }
 
 func (ecInfo *EcVolumeInfo) RemoveShardId(id ShardId) {
-	ecInfo.shardIds &^= (1 << id)
+	ecInfo.ShardBits = ecInfo.ShardBits.RemoveShardId(id)
 }
 
 func (ecInfo *EcVolumeInfo) HasShardId(id ShardId) bool {
-	return ecInfo.shardIds&(1<<id) > 0
+	return ecInfo.ShardBits.HasShardId(id)
 }
 
 func (ecInfo *EcVolumeInfo) ShardIds() (ret []ShardId) {
-	for i := ShardId(0); i < DataShardsCount+ParityShardsCount; i++ {
-		if ecInfo.HasShardId(i) {
-			ret = append(ret, i)
-		}
-	}
-	return
+	return ecInfo.ShardBits.ShardIds()
 }
 
 func (ecInfo *EcVolumeInfo) Minus(other *EcVolumeInfo) (*EcVolumeInfo) {
 	ret := &EcVolumeInfo{
 		VolumeId:   ecInfo.VolumeId,
 		Collection: ecInfo.Collection,
-		shardIds:   ecInfo.shardIds &^ other.shardIds,
+		ShardBits:  ecInfo.ShardBits.Minus(other.ShardBits),
 	}
 
 	return ret
 }
 
-func (ecInfo *EcVolumeInfo) ToVolumeEcShardInformationMessage() (ret []*master_pb.VolumeEcShardInformationMessage) {
-	for _, shard := range ecInfo.ShardIds() {
-		ret = append(ret, &master_pb.VolumeEcShardInformationMessage{
-			Id:         uint32(ecInfo.VolumeId),
-			EcIndex:    uint32(shard),
-			Collection: ecInfo.Collection,
-		})
+func (ecInfo *EcVolumeInfo) ToVolumeEcShardInformationMessage() (ret *master_pb.VolumeEcShardInformationMessage) {
+	return &master_pb.VolumeEcShardInformationMessage{
+		Id:          uint32(ecInfo.VolumeId),
+		EcIndexBits: uint32(ecInfo.ShardBits),
+		Collection:  ecInfo.Collection,
+	}
+}
+
+type ShardBits uint32 // use bits to indicate the shard id, use 32 bits just for possible future extension
 
+func (b ShardBits) AddShardId(id ShardId) ShardBits {
+	return b | (1 << id)
+}
+
+func (b ShardBits) RemoveShardId(id ShardId) ShardBits {
+	return b &^ (1 << id)
+}
+
+func (b ShardBits) HasShardId(id ShardId) bool {
+	return b&(1<<id) > 0
+}
+
+func (b ShardBits) ShardIds() (ret []ShardId) {
+	for i := ShardId(0); i < DataShardsCount+ParityShardsCount; i++ {
+		if b.HasShardId(i) {
+			ret = append(ret, i)
+		}
 	}
 	return
 }
 
-func (ecInfo *EcVolumeInfo) String() string {
-	return fmt.Sprintf("id:%d shard:%v collection:%v", ecInfo.VolumeId, ecInfo.ShardIds(), ecInfo.Collection)
+func (b ShardBits) Minus(other ShardBits) (ShardBits) {
+	return b &^ other
 }