[VOL-4291] Rw-core updates for gRPC migration

Change-Id: I8d5a554409115b29318089671ca4e1ab3fa98810
diff --git a/vendor/github.com/coreos/etcd/etcdserver/corrupt.go b/vendor/github.com/coreos/etcd/etcdserver/corrupt.go
new file mode 100644
index 0000000..d998ec5
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/etcdserver/corrupt.go
@@ -0,0 +1,262 @@
+// 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 (
+	"context"
+	"fmt"
+	"time"
+
+	"github.com/coreos/etcd/clientv3"
+	"github.com/coreos/etcd/etcdserver/api/v3rpc/rpctypes"
+	pb "github.com/coreos/etcd/etcdserver/etcdserverpb"
+	"github.com/coreos/etcd/mvcc"
+	"github.com/coreos/etcd/pkg/types"
+)
+
+// CheckInitialHashKV compares initial hash values with its peers
+// before serving any peer/client traffic. Only mismatch when hashes
+// are different at requested revision, with same compact revision.
+func (s *EtcdServer) CheckInitialHashKV() error {
+	if !s.Cfg.InitialCorruptCheck {
+		return nil
+	}
+
+	plog.Infof("%s starting initial corruption check with timeout %v...", s.ID(), s.Cfg.ReqTimeout())
+	h, rev, crev, err := s.kv.HashByRev(0)
+	if err != nil {
+		return fmt.Errorf("%s failed to fetch hash (%v)", s.ID(), err)
+	}
+	peers := s.getPeerHashKVs(rev)
+	mismatch := 0
+	for _, p := range peers {
+		if p.resp != nil {
+			peerID := types.ID(p.resp.Header.MemberId)
+			if h != p.resp.Hash {
+				if crev == p.resp.CompactRevision {
+					plog.Errorf("%s's hash %d != %s's hash %d (revision %d, peer revision %d, compact revision %d)", s.ID(), h, peerID, p.resp.Hash, rev, p.resp.Header.Revision, crev)
+					mismatch++
+				} else {
+					plog.Warningf("%s cannot check hash of peer(%s): peer has a different compact revision %d (revision:%d)", s.ID(), peerID, p.resp.CompactRevision, rev)
+				}
+			}
+			continue
+		}
+		if p.err != nil {
+			switch p.err {
+			case rpctypes.ErrFutureRev:
+				plog.Warningf("%s cannot check the hash of peer(%q) at revision %d: peer is lagging behind(%q)", s.ID(), p.eps, rev, p.err.Error())
+			case rpctypes.ErrCompacted:
+				plog.Warningf("%s cannot check the hash of peer(%q) at revision %d: local node is lagging behind(%q)", s.ID(), p.eps, rev, p.err.Error())
+			}
+		}
+	}
+	if mismatch > 0 {
+		return fmt.Errorf("%s found data inconsistency with peers", s.ID())
+	}
+
+	plog.Infof("%s succeeded on initial corruption checking: no corruption", s.ID())
+	return nil
+}
+
+func (s *EtcdServer) monitorKVHash() {
+	t := s.Cfg.CorruptCheckTime
+	if t == 0 {
+		return
+	}
+	plog.Infof("enabled corruption checking with %s interval", t)
+	for {
+		select {
+		case <-s.stopping:
+			return
+		case <-time.After(t):
+		}
+		if !s.isLeader() {
+			continue
+		}
+		if err := s.checkHashKV(); err != nil {
+			plog.Debugf("check hash kv failed %v", err)
+		}
+	}
+}
+
+func (s *EtcdServer) checkHashKV() error {
+	h, rev, crev, err := s.kv.HashByRev(0)
+	if err != nil {
+		plog.Fatalf("failed to hash kv store (%v)", err)
+	}
+	peers := s.getPeerHashKVs(rev)
+
+	ctx, cancel := context.WithTimeout(context.Background(), s.Cfg.ReqTimeout())
+	err = s.linearizableReadNotify(ctx)
+	cancel()
+	if err != nil {
+		return err
+	}
+
+	h2, rev2, crev2, err := s.kv.HashByRev(0)
+	if err != nil {
+		plog.Warningf("failed to hash kv store (%v)", err)
+		return err
+	}
+
+	alarmed := false
+	mismatch := func(id uint64) {
+		if alarmed {
+			return
+		}
+		alarmed = true
+		a := &pb.AlarmRequest{
+			MemberID: uint64(id),
+			Action:   pb.AlarmRequest_ACTIVATE,
+			Alarm:    pb.AlarmType_CORRUPT,
+		}
+		s.goAttach(func() {
+			s.raftRequest(s.ctx, pb.InternalRaftRequest{Alarm: a})
+		})
+	}
+
+	if h2 != h && rev2 == rev && crev == crev2 {
+		plog.Warningf("mismatched hashes %d and %d for revision %d", h, h2, rev)
+		mismatch(uint64(s.ID()))
+	}
+
+	for _, p := range peers {
+		if p.resp == nil {
+			continue
+		}
+		id := p.resp.Header.MemberId
+
+		// leader expects follower's latest revision less than or equal to leader's
+		if p.resp.Header.Revision > rev2 {
+			plog.Warningf(
+				"revision %d from member %v, expected at most %d",
+				p.resp.Header.Revision,
+				types.ID(id),
+				rev2)
+			mismatch(id)
+		}
+
+		// leader expects follower's latest compact revision less than or equal to leader's
+		if p.resp.CompactRevision > crev2 {
+			plog.Warningf(
+				"compact revision %d from member %v, expected at most %d",
+				p.resp.CompactRevision,
+				types.ID(id),
+				crev2,
+			)
+			mismatch(id)
+		}
+
+		// follower's compact revision is leader's old one, then hashes must match
+		if p.resp.CompactRevision == crev && p.resp.Hash != h {
+			plog.Warningf(
+				"hash %d at revision %d from member %v, expected hash %d",
+				p.resp.Hash,
+				rev,
+				types.ID(id),
+				h,
+			)
+			mismatch(id)
+		}
+	}
+	return nil
+}
+
+type peerHashKVResp struct {
+	resp *clientv3.HashKVResponse
+	err  error
+	eps  []string
+}
+
+func (s *EtcdServer) getPeerHashKVs(rev int64) (resps []*peerHashKVResp) {
+	// TODO: handle the case when "s.cluster.Members" have not
+	// been populated (e.g. no snapshot to load from disk)
+	mbs := s.cluster.Members()
+	pURLs := make([][]string, len(mbs))
+	for _, m := range mbs {
+		if m.ID == s.ID() {
+			continue
+		}
+		pURLs = append(pURLs, m.PeerURLs)
+	}
+
+	for _, purls := range pURLs {
+		if len(purls) == 0 {
+			continue
+		}
+		cli, cerr := clientv3.New(clientv3.Config{
+			DialTimeout: s.Cfg.ReqTimeout(),
+			Endpoints:   purls,
+		})
+		if cerr != nil {
+			plog.Warningf("%s failed to create client to peer %q for hash checking (%q)", s.ID(), purls, cerr.Error())
+			continue
+		}
+
+		respsLen := len(resps)
+		for _, c := range cli.Endpoints() {
+			ctx, cancel := context.WithTimeout(context.Background(), s.Cfg.ReqTimeout())
+			var resp *clientv3.HashKVResponse
+			resp, cerr = cli.HashKV(ctx, c, rev)
+			cancel()
+			if cerr == nil {
+				resps = append(resps, &peerHashKVResp{resp: resp})
+				break
+			}
+			plog.Warningf("%s hash-kv error %q on peer %q with revision %d", s.ID(), cerr.Error(), c, rev)
+		}
+		cli.Close()
+
+		if respsLen == len(resps) {
+			resps = append(resps, &peerHashKVResp{err: cerr, eps: purls})
+		}
+	}
+	return resps
+}
+
+type applierV3Corrupt struct {
+	applierV3
+}
+
+func newApplierV3Corrupt(a applierV3) *applierV3Corrupt { return &applierV3Corrupt{a} }
+
+func (a *applierV3Corrupt) Put(txn mvcc.TxnWrite, p *pb.PutRequest) (*pb.PutResponse, error) {
+	return nil, ErrCorrupt
+}
+
+func (a *applierV3Corrupt) Range(txn mvcc.TxnRead, p *pb.RangeRequest) (*pb.RangeResponse, error) {
+	return nil, ErrCorrupt
+}
+
+func (a *applierV3Corrupt) DeleteRange(txn mvcc.TxnWrite, p *pb.DeleteRangeRequest) (*pb.DeleteRangeResponse, error) {
+	return nil, ErrCorrupt
+}
+
+func (a *applierV3Corrupt) Txn(rt *pb.TxnRequest) (*pb.TxnResponse, error) {
+	return nil, ErrCorrupt
+}
+
+func (a *applierV3Corrupt) Compaction(compaction *pb.CompactionRequest) (*pb.CompactionResponse, <-chan struct{}, error) {
+	return nil, nil, ErrCorrupt
+}
+
+func (a *applierV3Corrupt) LeaseGrant(lc *pb.LeaseGrantRequest) (*pb.LeaseGrantResponse, error) {
+	return nil, ErrCorrupt
+}
+
+func (a *applierV3Corrupt) LeaseRevoke(lc *pb.LeaseRevokeRequest) (*pb.LeaseRevokeResponse, error) {
+	return nil, ErrCorrupt
+}