[VOL-4291] Rw-core updates for gRPC migration
Change-Id: I8d5a554409115b29318089671ca4e1ab3fa98810
diff --git a/vendor/github.com/coreos/etcd/etcdserver/backend.go b/vendor/github.com/coreos/etcd/etcdserver/backend.go
new file mode 100644
index 0000000..fe2f865
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/etcdserver/backend.go
@@ -0,0 +1,81 @@
+// Copyright 2017 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package etcdserver
+
+import (
+ "fmt"
+ "os"
+ "time"
+
+ "github.com/coreos/etcd/lease"
+ "github.com/coreos/etcd/mvcc"
+ "github.com/coreos/etcd/mvcc/backend"
+ "github.com/coreos/etcd/raft/raftpb"
+ "github.com/coreos/etcd/snap"
+)
+
+func newBackend(cfg ServerConfig) backend.Backend {
+ bcfg := backend.DefaultBackendConfig()
+ bcfg.Path = cfg.backendPath()
+ if cfg.QuotaBackendBytes > 0 && cfg.QuotaBackendBytes != DefaultQuotaBytes {
+ // permit 10% excess over quota for disarm
+ bcfg.MmapSize = uint64(cfg.QuotaBackendBytes + cfg.QuotaBackendBytes/10)
+ }
+ return backend.New(bcfg)
+}
+
+// openSnapshotBackend renames a snapshot db to the current etcd db and opens it.
+func openSnapshotBackend(cfg ServerConfig, ss *snap.Snapshotter, snapshot raftpb.Snapshot) (backend.Backend, error) {
+ snapPath, err := ss.DBFilePath(snapshot.Metadata.Index)
+ if err != nil {
+ return nil, fmt.Errorf("database snapshot file path error: %v", err)
+ }
+ if err := os.Rename(snapPath, cfg.backendPath()); err != nil {
+ return nil, fmt.Errorf("rename snapshot file error: %v", err)
+ }
+ return openBackend(cfg), nil
+}
+
+// openBackend returns a backend using the current etcd db.
+func openBackend(cfg ServerConfig) backend.Backend {
+ fn := cfg.backendPath()
+ beOpened := make(chan backend.Backend)
+ go func() {
+ beOpened <- newBackend(cfg)
+ }()
+ select {
+ case be := <-beOpened:
+ return be
+ case <-time.After(10 * time.Second):
+ plog.Warningf("another etcd process is using %q and holds the file lock, or loading backend file is taking >10 seconds", fn)
+ plog.Warningf("waiting for it to exit before starting...")
+ }
+ return <-beOpened
+}
+
+// recoverBackendSnapshot recovers the DB from a snapshot in case etcd crashes
+// before updating the backend db after persisting raft snapshot to disk,
+// violating the invariant snapshot.Metadata.Index < db.consistentIndex. In this
+// case, replace the db with the snapshot db sent by the leader.
+func recoverSnapshotBackend(cfg ServerConfig, oldbe backend.Backend, snapshot raftpb.Snapshot) (backend.Backend, error) {
+ var cIndex consistentIndex
+ kv := mvcc.New(oldbe, &lease.FakeLessor{}, nil, &cIndex)
+ defer kv.Close()
+ if snapshot.Metadata.Index <= kv.ConsistentIndex() {
+ return oldbe, nil
+ }
+ oldbe.Close()
+ return openSnapshotBackend(cfg, snap.New(cfg.SnapDir()), snapshot)
+}