[VOL-4291] Rw-core updates for gRPC migration
Change-Id: I8d5a554409115b29318089671ca4e1ab3fa98810
diff --git a/vendor/github.com/coreos/etcd/wal/util.go b/vendor/github.com/coreos/etcd/wal/util.go
new file mode 100644
index 0000000..5c56e22
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/wal/util.go
@@ -0,0 +1,107 @@
+// Copyright 2015 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 wal
+
+import (
+ "errors"
+ "fmt"
+ "strings"
+
+ "github.com/coreos/etcd/pkg/fileutil"
+)
+
+var (
+ badWalName = errors.New("bad wal name")
+)
+
+func Exist(dirpath string) bool {
+ names, err := fileutil.ReadDir(dirpath)
+ if err != nil {
+ return false
+ }
+ return len(names) != 0
+}
+
+// searchIndex returns the last array index of names whose raft index section is
+// equal to or smaller than the given index.
+// The given names MUST be sorted.
+func searchIndex(names []string, index uint64) (int, bool) {
+ for i := len(names) - 1; i >= 0; i-- {
+ name := names[i]
+ _, curIndex, err := parseWalName(name)
+ if err != nil {
+ plog.Panicf("parse correct name should never fail: %v", err)
+ }
+ if index >= curIndex {
+ return i, true
+ }
+ }
+ return -1, false
+}
+
+// names should have been sorted based on sequence number.
+// isValidSeq checks whether seq increases continuously.
+func isValidSeq(names []string) bool {
+ var lastSeq uint64
+ for _, name := range names {
+ curSeq, _, err := parseWalName(name)
+ if err != nil {
+ plog.Panicf("parse correct name should never fail: %v", err)
+ }
+ if lastSeq != 0 && lastSeq != curSeq-1 {
+ return false
+ }
+ lastSeq = curSeq
+ }
+ return true
+}
+func readWalNames(dirpath string) ([]string, error) {
+ names, err := fileutil.ReadDir(dirpath)
+ if err != nil {
+ return nil, err
+ }
+ wnames := checkWalNames(names)
+ if len(wnames) == 0 {
+ return nil, ErrFileNotFound
+ }
+ return wnames, nil
+}
+
+func checkWalNames(names []string) []string {
+ wnames := make([]string, 0)
+ for _, name := range names {
+ if _, _, err := parseWalName(name); err != nil {
+ // don't complain about left over tmp files
+ if !strings.HasSuffix(name, ".tmp") {
+ plog.Warningf("ignored file %v in wal", name)
+ }
+ continue
+ }
+ wnames = append(wnames, name)
+ }
+ return wnames
+}
+
+func parseWalName(str string) (seq, index uint64, err error) {
+ if !strings.HasSuffix(str, ".wal") {
+ return 0, 0, badWalName
+ }
+ _, err = fmt.Sscanf(str, "%016x-%016x.wal", &seq, &index)
+ return seq, index, err
+}
+
+func walName(seq, index uint64) string {
+ return fmt.Sprintf("%016x-%016x.wal", seq, index)
+}