[VOL-4290] Voltha go library updates for gRPC migration

Change-Id: I1aa2774beb6b7ed7419bc45aeb53fcae8a8ecda0
diff --git a/vendor/google.golang.org/protobuf/encoding/prototext/encode.go b/vendor/google.golang.org/protobuf/encoding/prototext/encode.go
new file mode 100644
index 0000000..8d5304d
--- /dev/null
+++ b/vendor/google.golang.org/protobuf/encoding/prototext/encode.go
@@ -0,0 +1,371 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package prototext
+
+import (
+	"fmt"
+	"strconv"
+	"unicode/utf8"
+
+	"google.golang.org/protobuf/encoding/protowire"
+	"google.golang.org/protobuf/internal/encoding/messageset"
+	"google.golang.org/protobuf/internal/encoding/text"
+	"google.golang.org/protobuf/internal/errors"
+	"google.golang.org/protobuf/internal/flags"
+	"google.golang.org/protobuf/internal/genid"
+	"google.golang.org/protobuf/internal/order"
+	"google.golang.org/protobuf/internal/pragma"
+	"google.golang.org/protobuf/internal/strs"
+	"google.golang.org/protobuf/proto"
+	"google.golang.org/protobuf/reflect/protoreflect"
+	pref "google.golang.org/protobuf/reflect/protoreflect"
+	"google.golang.org/protobuf/reflect/protoregistry"
+)
+
+const defaultIndent = "  "
+
+// Format formats the message as a multiline string.
+// This function is only intended for human consumption and ignores errors.
+// Do not depend on the output being stable. It may change over time across
+// different versions of the program.
+func Format(m proto.Message) string {
+	return MarshalOptions{Multiline: true}.Format(m)
+}
+
+// Marshal writes the given proto.Message in textproto format using default
+// options. Do not depend on the output being stable. It may change over time
+// across different versions of the program.
+func Marshal(m proto.Message) ([]byte, error) {
+	return MarshalOptions{}.Marshal(m)
+}
+
+// MarshalOptions is a configurable text format marshaler.
+type MarshalOptions struct {
+	pragma.NoUnkeyedLiterals
+
+	// Multiline specifies whether the marshaler should format the output in
+	// indented-form with every textual element on a new line.
+	// If Indent is an empty string, then an arbitrary indent is chosen.
+	Multiline bool
+
+	// Indent specifies the set of indentation characters to use in a multiline
+	// formatted output such that every entry is preceded by Indent and
+	// terminated by a newline. If non-empty, then Multiline is treated as true.
+	// Indent can only be composed of space or tab characters.
+	Indent string
+
+	// EmitASCII specifies whether to format strings and bytes as ASCII only
+	// as opposed to using UTF-8 encoding when possible.
+	EmitASCII bool
+
+	// allowInvalidUTF8 specifies whether to permit the encoding of strings
+	// with invalid UTF-8. This is unexported as it is intended to only
+	// be specified by the Format method.
+	allowInvalidUTF8 bool
+
+	// AllowPartial allows messages that have missing required fields to marshal
+	// without returning an error. If AllowPartial is false (the default),
+	// Marshal will return error if there are any missing required fields.
+	AllowPartial bool
+
+	// EmitUnknown specifies whether to emit unknown fields in the output.
+	// If specified, the unmarshaler may be unable to parse the output.
+	// The default is to exclude unknown fields.
+	EmitUnknown bool
+
+	// Resolver is used for looking up types when expanding google.protobuf.Any
+	// messages. If nil, this defaults to using protoregistry.GlobalTypes.
+	Resolver interface {
+		protoregistry.ExtensionTypeResolver
+		protoregistry.MessageTypeResolver
+	}
+}
+
+// Format formats the message as a string.
+// This method is only intended for human consumption and ignores errors.
+// Do not depend on the output being stable. It may change over time across
+// different versions of the program.
+func (o MarshalOptions) Format(m proto.Message) string {
+	if m == nil || !m.ProtoReflect().IsValid() {
+		return "<nil>" // invalid syntax, but okay since this is for debugging
+	}
+	o.allowInvalidUTF8 = true
+	o.AllowPartial = true
+	o.EmitUnknown = true
+	b, _ := o.Marshal(m)
+	return string(b)
+}
+
+// Marshal writes the given proto.Message in textproto format using options in
+// MarshalOptions object. Do not depend on the output being stable. It may
+// change over time across different versions of the program.
+func (o MarshalOptions) Marshal(m proto.Message) ([]byte, error) {
+	return o.marshal(m)
+}
+
+// marshal is a centralized function that all marshal operations go through.
+// For profiling purposes, avoid changing the name of this function or
+// introducing other code paths for marshal that do not go through this.
+func (o MarshalOptions) marshal(m proto.Message) ([]byte, error) {
+	var delims = [2]byte{'{', '}'}
+
+	if o.Multiline && o.Indent == "" {
+		o.Indent = defaultIndent
+	}
+	if o.Resolver == nil {
+		o.Resolver = protoregistry.GlobalTypes
+	}
+
+	internalEnc, err := text.NewEncoder(o.Indent, delims, o.EmitASCII)
+	if err != nil {
+		return nil, err
+	}
+
+	// Treat nil message interface as an empty message,
+	// in which case there is nothing to output.
+	if m == nil {
+		return []byte{}, nil
+	}
+
+	enc := encoder{internalEnc, o}
+	err = enc.marshalMessage(m.ProtoReflect(), false)
+	if err != nil {
+		return nil, err
+	}
+	out := enc.Bytes()
+	if len(o.Indent) > 0 && len(out) > 0 {
+		out = append(out, '\n')
+	}
+	if o.AllowPartial {
+		return out, nil
+	}
+	return out, proto.CheckInitialized(m)
+}
+
+type encoder struct {
+	*text.Encoder
+	opts MarshalOptions
+}
+
+// marshalMessage marshals the given protoreflect.Message.
+func (e encoder) marshalMessage(m pref.Message, inclDelims bool) error {
+	messageDesc := m.Descriptor()
+	if !flags.ProtoLegacy && messageset.IsMessageSet(messageDesc) {
+		return errors.New("no support for proto1 MessageSets")
+	}
+
+	if inclDelims {
+		e.StartMessage()
+		defer e.EndMessage()
+	}
+
+	// Handle Any expansion.
+	if messageDesc.FullName() == genid.Any_message_fullname {
+		if e.marshalAny(m) {
+			return nil
+		}
+		// If unable to expand, continue on to marshal Any as a regular message.
+	}
+
+	// Marshal fields.
+	var err error
+	order.RangeFields(m, order.IndexNameFieldOrder, func(fd protoreflect.FieldDescriptor, v protoreflect.Value) bool {
+		if err = e.marshalField(fd.TextName(), v, fd); err != nil {
+			return false
+		}
+		return true
+	})
+	if err != nil {
+		return err
+	}
+
+	// Marshal unknown fields.
+	if e.opts.EmitUnknown {
+		e.marshalUnknown(m.GetUnknown())
+	}
+
+	return nil
+}
+
+// marshalField marshals the given field with protoreflect.Value.
+func (e encoder) marshalField(name string, val pref.Value, fd pref.FieldDescriptor) error {
+	switch {
+	case fd.IsList():
+		return e.marshalList(name, val.List(), fd)
+	case fd.IsMap():
+		return e.marshalMap(name, val.Map(), fd)
+	default:
+		e.WriteName(name)
+		return e.marshalSingular(val, fd)
+	}
+}
+
+// marshalSingular marshals the given non-repeated field value. This includes
+// all scalar types, enums, messages, and groups.
+func (e encoder) marshalSingular(val pref.Value, fd pref.FieldDescriptor) error {
+	kind := fd.Kind()
+	switch kind {
+	case pref.BoolKind:
+		e.WriteBool(val.Bool())
+
+	case pref.StringKind:
+		s := val.String()
+		if !e.opts.allowInvalidUTF8 && strs.EnforceUTF8(fd) && !utf8.ValidString(s) {
+			return errors.InvalidUTF8(string(fd.FullName()))
+		}
+		e.WriteString(s)
+
+	case pref.Int32Kind, pref.Int64Kind,
+		pref.Sint32Kind, pref.Sint64Kind,
+		pref.Sfixed32Kind, pref.Sfixed64Kind:
+		e.WriteInt(val.Int())
+
+	case pref.Uint32Kind, pref.Uint64Kind,
+		pref.Fixed32Kind, pref.Fixed64Kind:
+		e.WriteUint(val.Uint())
+
+	case pref.FloatKind:
+		// Encoder.WriteFloat handles the special numbers NaN and infinites.
+		e.WriteFloat(val.Float(), 32)
+
+	case pref.DoubleKind:
+		// Encoder.WriteFloat handles the special numbers NaN and infinites.
+		e.WriteFloat(val.Float(), 64)
+
+	case pref.BytesKind:
+		e.WriteString(string(val.Bytes()))
+
+	case pref.EnumKind:
+		num := val.Enum()
+		if desc := fd.Enum().Values().ByNumber(num); desc != nil {
+			e.WriteLiteral(string(desc.Name()))
+		} else {
+			// Use numeric value if there is no enum description.
+			e.WriteInt(int64(num))
+		}
+
+	case pref.MessageKind, pref.GroupKind:
+		return e.marshalMessage(val.Message(), true)
+
+	default:
+		panic(fmt.Sprintf("%v has unknown kind: %v", fd.FullName(), kind))
+	}
+	return nil
+}
+
+// marshalList marshals the given protoreflect.List as multiple name-value fields.
+func (e encoder) marshalList(name string, list pref.List, fd pref.FieldDescriptor) error {
+	size := list.Len()
+	for i := 0; i < size; i++ {
+		e.WriteName(name)
+		if err := e.marshalSingular(list.Get(i), fd); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+// marshalMap marshals the given protoreflect.Map as multiple name-value fields.
+func (e encoder) marshalMap(name string, mmap pref.Map, fd pref.FieldDescriptor) error {
+	var err error
+	order.RangeEntries(mmap, order.GenericKeyOrder, func(key pref.MapKey, val pref.Value) bool {
+		e.WriteName(name)
+		e.StartMessage()
+		defer e.EndMessage()
+
+		e.WriteName(string(genid.MapEntry_Key_field_name))
+		err = e.marshalSingular(key.Value(), fd.MapKey())
+		if err != nil {
+			return false
+		}
+
+		e.WriteName(string(genid.MapEntry_Value_field_name))
+		err = e.marshalSingular(val, fd.MapValue())
+		if err != nil {
+			return false
+		}
+		return true
+	})
+	return err
+}
+
+// marshalUnknown parses the given []byte and marshals fields out.
+// This function assumes proper encoding in the given []byte.
+func (e encoder) marshalUnknown(b []byte) {
+	const dec = 10
+	const hex = 16
+	for len(b) > 0 {
+		num, wtype, n := protowire.ConsumeTag(b)
+		b = b[n:]
+		e.WriteName(strconv.FormatInt(int64(num), dec))
+
+		switch wtype {
+		case protowire.VarintType:
+			var v uint64
+			v, n = protowire.ConsumeVarint(b)
+			e.WriteUint(v)
+		case protowire.Fixed32Type:
+			var v uint32
+			v, n = protowire.ConsumeFixed32(b)
+			e.WriteLiteral("0x" + strconv.FormatUint(uint64(v), hex))
+		case protowire.Fixed64Type:
+			var v uint64
+			v, n = protowire.ConsumeFixed64(b)
+			e.WriteLiteral("0x" + strconv.FormatUint(v, hex))
+		case protowire.BytesType:
+			var v []byte
+			v, n = protowire.ConsumeBytes(b)
+			e.WriteString(string(v))
+		case protowire.StartGroupType:
+			e.StartMessage()
+			var v []byte
+			v, n = protowire.ConsumeGroup(num, b)
+			e.marshalUnknown(v)
+			e.EndMessage()
+		default:
+			panic(fmt.Sprintf("prototext: error parsing unknown field wire type: %v", wtype))
+		}
+
+		b = b[n:]
+	}
+}
+
+// marshalAny marshals the given google.protobuf.Any message in expanded form.
+// It returns true if it was able to marshal, else false.
+func (e encoder) marshalAny(any pref.Message) bool {
+	// Construct the embedded message.
+	fds := any.Descriptor().Fields()
+	fdType := fds.ByNumber(genid.Any_TypeUrl_field_number)
+	typeURL := any.Get(fdType).String()
+	mt, err := e.opts.Resolver.FindMessageByURL(typeURL)
+	if err != nil {
+		return false
+	}
+	m := mt.New().Interface()
+
+	// Unmarshal bytes into embedded message.
+	fdValue := fds.ByNumber(genid.Any_Value_field_number)
+	value := any.Get(fdValue)
+	err = proto.UnmarshalOptions{
+		AllowPartial: true,
+		Resolver:     e.opts.Resolver,
+	}.Unmarshal(value.Bytes(), m)
+	if err != nil {
+		return false
+	}
+
+	// Get current encoder position. If marshaling fails, reset encoder output
+	// back to this position.
+	pos := e.Snapshot()
+
+	// Field name is the proto field name enclosed in [].
+	e.WriteName("[" + typeURL + "]")
+	err = e.marshalMessage(m.ProtoReflect(), true)
+	if err != nil {
+		e.Reset(pos)
+		return false
+	}
+	return true
+}