[VOL-1349] EPON OLT adapter (package B)

Change-Id: I634ef62c53813dcf4456f54948f13e06358e263c
diff --git a/vendor/go.etcd.io/etcd/clientv3/logger.go b/vendor/go.etcd.io/etcd/clientv3/logger.go
new file mode 100644
index 0000000..f5ae010
--- /dev/null
+++ b/vendor/go.etcd.io/etcd/clientv3/logger.go
@@ -0,0 +1,101 @@
+// Copyright 2016 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 clientv3
+
+import (
+	"io/ioutil"
+	"sync"
+
+	"go.etcd.io/etcd/pkg/logutil"
+
+	"google.golang.org/grpc/grpclog"
+)
+
+var (
+	lgMu sync.RWMutex
+	lg   logutil.Logger
+)
+
+type settableLogger struct {
+	l  grpclog.LoggerV2
+	mu sync.RWMutex
+}
+
+func init() {
+	// disable client side logs by default
+	lg = &settableLogger{}
+	SetLogger(grpclog.NewLoggerV2(ioutil.Discard, ioutil.Discard, ioutil.Discard))
+}
+
+// SetLogger sets client-side Logger.
+func SetLogger(l grpclog.LoggerV2) {
+	lgMu.Lock()
+	lg = logutil.NewLogger(l)
+	// override grpclog so that any changes happen with locking
+	grpclog.SetLoggerV2(lg)
+	lgMu.Unlock()
+}
+
+// GetLogger returns the current logutil.Logger.
+func GetLogger() logutil.Logger {
+	lgMu.RLock()
+	l := lg
+	lgMu.RUnlock()
+	return l
+}
+
+// NewLogger returns a new Logger with logutil.Logger.
+func NewLogger(gl grpclog.LoggerV2) logutil.Logger {
+	return &settableLogger{l: gl}
+}
+
+func (s *settableLogger) get() grpclog.LoggerV2 {
+	s.mu.RLock()
+	l := s.l
+	s.mu.RUnlock()
+	return l
+}
+
+// implement the grpclog.LoggerV2 interface
+
+func (s *settableLogger) Info(args ...interface{})                 { s.get().Info(args...) }
+func (s *settableLogger) Infof(format string, args ...interface{}) { s.get().Infof(format, args...) }
+func (s *settableLogger) Infoln(args ...interface{})               { s.get().Infoln(args...) }
+func (s *settableLogger) Warning(args ...interface{})              { s.get().Warning(args...) }
+func (s *settableLogger) Warningf(format string, args ...interface{}) {
+	s.get().Warningf(format, args...)
+}
+func (s *settableLogger) Warningln(args ...interface{}) { s.get().Warningln(args...) }
+func (s *settableLogger) Error(args ...interface{})     { s.get().Error(args...) }
+func (s *settableLogger) Errorf(format string, args ...interface{}) {
+	s.get().Errorf(format, args...)
+}
+func (s *settableLogger) Errorln(args ...interface{})               { s.get().Errorln(args...) }
+func (s *settableLogger) Fatal(args ...interface{})                 { s.get().Fatal(args...) }
+func (s *settableLogger) Fatalf(format string, args ...interface{}) { s.get().Fatalf(format, args...) }
+func (s *settableLogger) Fatalln(args ...interface{})               { s.get().Fatalln(args...) }
+func (s *settableLogger) Print(args ...interface{})                 { s.get().Info(args...) }
+func (s *settableLogger) Printf(format string, args ...interface{}) { s.get().Infof(format, args...) }
+func (s *settableLogger) Println(args ...interface{})               { s.get().Infoln(args...) }
+func (s *settableLogger) V(l int) bool                              { return s.get().V(l) }
+func (s *settableLogger) Lvl(lvl int) grpclog.LoggerV2 {
+	s.mu.RLock()
+	l := s.l
+	s.mu.RUnlock()
+	if l.V(lvl) {
+		return s
+	}
+	return logutil.NewDiscardLogger()
+}