VOL-1868 move simulated onu from voltha-go to voltha-simonu-adapter

Sourced from voltha-go commit 251a11c0ffe60512318a644cd6ce0dc4e12f4018

Change-Id: Iab179bc2f3dd772ed7f488d1c03d1a84ba75e874
diff --git a/vendor/github.com/gogo/protobuf/proto/table_unmarshal.go b/vendor/github.com/gogo/protobuf/proto/table_unmarshal.go
new file mode 100644
index 0000000..bb2622f
--- /dev/null
+++ b/vendor/github.com/gogo/protobuf/proto/table_unmarshal.go
@@ -0,0 +1,2245 @@
+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2016 The Go Authors.  All rights reserved.
+// https://github.com/golang/protobuf
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package proto
+
+import (
+	"errors"
+	"fmt"
+	"io"
+	"math"
+	"reflect"
+	"strconv"
+	"strings"
+	"sync"
+	"sync/atomic"
+	"unicode/utf8"
+)
+
+// Unmarshal is the entry point from the generated .pb.go files.
+// This function is not intended to be used by non-generated code.
+// This function is not subject to any compatibility guarantee.
+// msg contains a pointer to a protocol buffer struct.
+// b is the data to be unmarshaled into the protocol buffer.
+// a is a pointer to a place to store cached unmarshal information.
+func (a *InternalMessageInfo) Unmarshal(msg Message, b []byte) error {
+	// Load the unmarshal information for this message type.
+	// The atomic load ensures memory consistency.
+	u := atomicLoadUnmarshalInfo(&a.unmarshal)
+	if u == nil {
+		// Slow path: find unmarshal info for msg, update a with it.
+		u = getUnmarshalInfo(reflect.TypeOf(msg).Elem())
+		atomicStoreUnmarshalInfo(&a.unmarshal, u)
+	}
+	// Then do the unmarshaling.
+	err := u.unmarshal(toPointer(&msg), b)
+	return err
+}
+
+type unmarshalInfo struct {
+	typ reflect.Type // type of the protobuf struct
+
+	// 0 = only typ field is initialized
+	// 1 = completely initialized
+	initialized     int32
+	lock            sync.Mutex                    // prevents double initialization
+	dense           []unmarshalFieldInfo          // fields indexed by tag #
+	sparse          map[uint64]unmarshalFieldInfo // fields indexed by tag #
+	reqFields       []string                      // names of required fields
+	reqMask         uint64                        // 1<<len(reqFields)-1
+	unrecognized    field                         // offset of []byte to put unrecognized data (or invalidField if we should throw it away)
+	extensions      field                         // offset of extensions field (of type proto.XXX_InternalExtensions), or invalidField if it does not exist
+	oldExtensions   field                         // offset of old-form extensions field (of type map[int]Extension)
+	extensionRanges []ExtensionRange              // if non-nil, implies extensions field is valid
+	isMessageSet    bool                          // if true, implies extensions field is valid
+
+	bytesExtensions field // offset of XXX_extensions with type []byte
+}
+
+// An unmarshaler takes a stream of bytes and a pointer to a field of a message.
+// It decodes the field, stores it at f, and returns the unused bytes.
+// w is the wire encoding.
+// b is the data after the tag and wire encoding have been read.
+type unmarshaler func(b []byte, f pointer, w int) ([]byte, error)
+
+type unmarshalFieldInfo struct {
+	// location of the field in the proto message structure.
+	field field
+
+	// function to unmarshal the data for the field.
+	unmarshal unmarshaler
+
+	// if a required field, contains a single set bit at this field's index in the required field list.
+	reqMask uint64
+
+	name string // name of the field, for error reporting
+}
+
+var (
+	unmarshalInfoMap  = map[reflect.Type]*unmarshalInfo{}
+	unmarshalInfoLock sync.Mutex
+)
+
+// getUnmarshalInfo returns the data structure which can be
+// subsequently used to unmarshal a message of the given type.
+// t is the type of the message (note: not pointer to message).
+func getUnmarshalInfo(t reflect.Type) *unmarshalInfo {
+	// It would be correct to return a new unmarshalInfo
+	// unconditionally. We would end up allocating one
+	// per occurrence of that type as a message or submessage.
+	// We use a cache here just to reduce memory usage.
+	unmarshalInfoLock.Lock()
+	defer unmarshalInfoLock.Unlock()
+	u := unmarshalInfoMap[t]
+	if u == nil {
+		u = &unmarshalInfo{typ: t}
+		// Note: we just set the type here. The rest of the fields
+		// will be initialized on first use.
+		unmarshalInfoMap[t] = u
+	}
+	return u
+}
+
+// unmarshal does the main work of unmarshaling a message.
+// u provides type information used to unmarshal the message.
+// m is a pointer to a protocol buffer message.
+// b is a byte stream to unmarshal into m.
+// This is top routine used when recursively unmarshaling submessages.
+func (u *unmarshalInfo) unmarshal(m pointer, b []byte) error {
+	if atomic.LoadInt32(&u.initialized) == 0 {
+		u.computeUnmarshalInfo()
+	}
+	if u.isMessageSet {
+		return unmarshalMessageSet(b, m.offset(u.extensions).toExtensions())
+	}
+	var reqMask uint64 // bitmask of required fields we've seen.
+	var errLater error
+	for len(b) > 0 {
+		// Read tag and wire type.
+		// Special case 1 and 2 byte varints.
+		var x uint64
+		if b[0] < 128 {
+			x = uint64(b[0])
+			b = b[1:]
+		} else if len(b) >= 2 && b[1] < 128 {
+			x = uint64(b[0]&0x7f) + uint64(b[1])<<7
+			b = b[2:]
+		} else {
+			var n int
+			x, n = decodeVarint(b)
+			if n == 0 {
+				return io.ErrUnexpectedEOF
+			}
+			b = b[n:]
+		}
+		tag := x >> 3
+		wire := int(x) & 7
+
+		// Dispatch on the tag to one of the unmarshal* functions below.
+		var f unmarshalFieldInfo
+		if tag < uint64(len(u.dense)) {
+			f = u.dense[tag]
+		} else {
+			f = u.sparse[tag]
+		}
+		if fn := f.unmarshal; fn != nil {
+			var err error
+			b, err = fn(b, m.offset(f.field), wire)
+			if err == nil {
+				reqMask |= f.reqMask
+				continue
+			}
+			if r, ok := err.(*RequiredNotSetError); ok {
+				// Remember this error, but keep parsing. We need to produce
+				// a full parse even if a required field is missing.
+				if errLater == nil {
+					errLater = r
+				}
+				reqMask |= f.reqMask
+				continue
+			}
+			if err != errInternalBadWireType {
+				if err == errInvalidUTF8 {
+					if errLater == nil {
+						fullName := revProtoTypes[reflect.PtrTo(u.typ)] + "." + f.name
+						errLater = &invalidUTF8Error{fullName}
+					}
+					continue
+				}
+				return err
+			}
+			// Fragments with bad wire type are treated as unknown fields.
+		}
+
+		// Unknown tag.
+		if !u.unrecognized.IsValid() {
+			// Don't keep unrecognized data; just skip it.
+			var err error
+			b, err = skipField(b, wire)
+			if err != nil {
+				return err
+			}
+			continue
+		}
+		// Keep unrecognized data around.
+		// maybe in extensions, maybe in the unrecognized field.
+		z := m.offset(u.unrecognized).toBytes()
+		var emap map[int32]Extension
+		var e Extension
+		for _, r := range u.extensionRanges {
+			if uint64(r.Start) <= tag && tag <= uint64(r.End) {
+				if u.extensions.IsValid() {
+					mp := m.offset(u.extensions).toExtensions()
+					emap = mp.extensionsWrite()
+					e = emap[int32(tag)]
+					z = &e.enc
+					break
+				}
+				if u.oldExtensions.IsValid() {
+					p := m.offset(u.oldExtensions).toOldExtensions()
+					emap = *p
+					if emap == nil {
+						emap = map[int32]Extension{}
+						*p = emap
+					}
+					e = emap[int32(tag)]
+					z = &e.enc
+					break
+				}
+				if u.bytesExtensions.IsValid() {
+					z = m.offset(u.bytesExtensions).toBytes()
+					break
+				}
+				panic("no extensions field available")
+			}
+		}
+		// Use wire type to skip data.
+		var err error
+		b0 := b
+		b, err = skipField(b, wire)
+		if err != nil {
+			return err
+		}
+		*z = encodeVarint(*z, tag<<3|uint64(wire))
+		*z = append(*z, b0[:len(b0)-len(b)]...)
+
+		if emap != nil {
+			emap[int32(tag)] = e
+		}
+	}
+	if reqMask != u.reqMask && errLater == nil {
+		// A required field of this message is missing.
+		for _, n := range u.reqFields {
+			if reqMask&1 == 0 {
+				errLater = &RequiredNotSetError{n}
+			}
+			reqMask >>= 1
+		}
+	}
+	return errLater
+}
+
+// computeUnmarshalInfo fills in u with information for use
+// in unmarshaling protocol buffers of type u.typ.
+func (u *unmarshalInfo) computeUnmarshalInfo() {
+	u.lock.Lock()
+	defer u.lock.Unlock()
+	if u.initialized != 0 {
+		return
+	}
+	t := u.typ
+	n := t.NumField()
+
+	// Set up the "not found" value for the unrecognized byte buffer.
+	// This is the default for proto3.
+	u.unrecognized = invalidField
+	u.extensions = invalidField
+	u.oldExtensions = invalidField
+	u.bytesExtensions = invalidField
+
+	// List of the generated type and offset for each oneof field.
+	type oneofField struct {
+		ityp  reflect.Type // interface type of oneof field
+		field field        // offset in containing message
+	}
+	var oneofFields []oneofField
+
+	for i := 0; i < n; i++ {
+		f := t.Field(i)
+		if f.Name == "XXX_unrecognized" {
+			// The byte slice used to hold unrecognized input is special.
+			if f.Type != reflect.TypeOf(([]byte)(nil)) {
+				panic("bad type for XXX_unrecognized field: " + f.Type.Name())
+			}
+			u.unrecognized = toField(&f)
+			continue
+		}
+		if f.Name == "XXX_InternalExtensions" {
+			// Ditto here.
+			if f.Type != reflect.TypeOf(XXX_InternalExtensions{}) {
+				panic("bad type for XXX_InternalExtensions field: " + f.Type.Name())
+			}
+			u.extensions = toField(&f)
+			if f.Tag.Get("protobuf_messageset") == "1" {
+				u.isMessageSet = true
+			}
+			continue
+		}
+		if f.Name == "XXX_extensions" {
+			// An older form of the extensions field.
+			if f.Type == reflect.TypeOf((map[int32]Extension)(nil)) {
+				u.oldExtensions = toField(&f)
+				continue
+			} else if f.Type == reflect.TypeOf(([]byte)(nil)) {
+				u.bytesExtensions = toField(&f)
+				continue
+			}
+			panic("bad type for XXX_extensions field: " + f.Type.Name())
+		}
+		if f.Name == "XXX_NoUnkeyedLiteral" || f.Name == "XXX_sizecache" {
+			continue
+		}
+
+		oneof := f.Tag.Get("protobuf_oneof")
+		if oneof != "" {
+			oneofFields = append(oneofFields, oneofField{f.Type, toField(&f)})
+			// The rest of oneof processing happens below.
+			continue
+		}
+
+		tags := f.Tag.Get("protobuf")
+		tagArray := strings.Split(tags, ",")
+		if len(tagArray) < 2 {
+			panic("protobuf tag not enough fields in " + t.Name() + "." + f.Name + ": " + tags)
+		}
+		tag, err := strconv.Atoi(tagArray[1])
+		if err != nil {
+			panic("protobuf tag field not an integer: " + tagArray[1])
+		}
+
+		name := ""
+		for _, tag := range tagArray[3:] {
+			if strings.HasPrefix(tag, "name=") {
+				name = tag[5:]
+			}
+		}
+
+		// Extract unmarshaling function from the field (its type and tags).
+		unmarshal := fieldUnmarshaler(&f)
+
+		// Required field?
+		var reqMask uint64
+		if tagArray[2] == "req" {
+			bit := len(u.reqFields)
+			u.reqFields = append(u.reqFields, name)
+			reqMask = uint64(1) << uint(bit)
+			// TODO: if we have more than 64 required fields, we end up
+			// not verifying that all required fields are present.
+			// Fix this, perhaps using a count of required fields?
+		}
+
+		// Store the info in the correct slot in the message.
+		u.setTag(tag, toField(&f), unmarshal, reqMask, name)
+	}
+
+	// Find any types associated with oneof fields.
+	// TODO: XXX_OneofFuncs returns more info than we need.  Get rid of some of it?
+	fn := reflect.Zero(reflect.PtrTo(t)).MethodByName("XXX_OneofFuncs")
+	// gogo: len(oneofFields) > 0 is needed for embedded oneof messages, without a marshaler and unmarshaler
+	if fn.IsValid() && len(oneofFields) > 0 {
+		res := fn.Call(nil)[3] // last return value from XXX_OneofFuncs: []interface{}
+		for i := res.Len() - 1; i >= 0; i-- {
+			v := res.Index(i)                             // interface{}
+			tptr := reflect.ValueOf(v.Interface()).Type() // *Msg_X
+			typ := tptr.Elem()                            // Msg_X
+
+			f := typ.Field(0) // oneof implementers have one field
+			baseUnmarshal := fieldUnmarshaler(&f)
+			tags := strings.Split(f.Tag.Get("protobuf"), ",")
+			fieldNum, err := strconv.Atoi(tags[1])
+			if err != nil {
+				panic("protobuf tag field not an integer: " + tags[1])
+			}
+			var name string
+			for _, tag := range tags {
+				if strings.HasPrefix(tag, "name=") {
+					name = strings.TrimPrefix(tag, "name=")
+					break
+				}
+			}
+
+			// Find the oneof field that this struct implements.
+			// Might take O(n^2) to process all of the oneofs, but who cares.
+			for _, of := range oneofFields {
+				if tptr.Implements(of.ityp) {
+					// We have found the corresponding interface for this struct.
+					// That lets us know where this struct should be stored
+					// when we encounter it during unmarshaling.
+					unmarshal := makeUnmarshalOneof(typ, of.ityp, baseUnmarshal)
+					u.setTag(fieldNum, of.field, unmarshal, 0, name)
+				}
+			}
+		}
+	}
+
+	// Get extension ranges, if any.
+	fn = reflect.Zero(reflect.PtrTo(t)).MethodByName("ExtensionRangeArray")
+	if fn.IsValid() {
+		if !u.extensions.IsValid() && !u.oldExtensions.IsValid() && !u.bytesExtensions.IsValid() {
+			panic("a message with extensions, but no extensions field in " + t.Name())
+		}
+		u.extensionRanges = fn.Call(nil)[0].Interface().([]ExtensionRange)
+	}
+
+	// Explicitly disallow tag 0. This will ensure we flag an error
+	// when decoding a buffer of all zeros. Without this code, we
+	// would decode and skip an all-zero buffer of even length.
+	// [0 0] is [tag=0/wiretype=varint varint-encoded-0].
+	u.setTag(0, zeroField, func(b []byte, f pointer, w int) ([]byte, error) {
+		return nil, fmt.Errorf("proto: %s: illegal tag 0 (wire type %d)", t, w)
+	}, 0, "")
+
+	// Set mask for required field check.
+	u.reqMask = uint64(1)<<uint(len(u.reqFields)) - 1
+
+	atomic.StoreInt32(&u.initialized, 1)
+}
+
+// setTag stores the unmarshal information for the given tag.
+// tag = tag # for field
+// field/unmarshal = unmarshal info for that field.
+// reqMask = if required, bitmask for field position in required field list. 0 otherwise.
+// name = short name of the field.
+func (u *unmarshalInfo) setTag(tag int, field field, unmarshal unmarshaler, reqMask uint64, name string) {
+	i := unmarshalFieldInfo{field: field, unmarshal: unmarshal, reqMask: reqMask, name: name}
+	n := u.typ.NumField()
+	if tag >= 0 && (tag < 16 || tag < 2*n) { // TODO: what are the right numbers here?
+		for len(u.dense) <= tag {
+			u.dense = append(u.dense, unmarshalFieldInfo{})
+		}
+		u.dense[tag] = i
+		return
+	}
+	if u.sparse == nil {
+		u.sparse = map[uint64]unmarshalFieldInfo{}
+	}
+	u.sparse[uint64(tag)] = i
+}
+
+// fieldUnmarshaler returns an unmarshaler for the given field.
+func fieldUnmarshaler(f *reflect.StructField) unmarshaler {
+	if f.Type.Kind() == reflect.Map {
+		return makeUnmarshalMap(f)
+	}
+	return typeUnmarshaler(f.Type, f.Tag.Get("protobuf"))
+}
+
+// typeUnmarshaler returns an unmarshaler for the given field type / field tag pair.
+func typeUnmarshaler(t reflect.Type, tags string) unmarshaler {
+	tagArray := strings.Split(tags, ",")
+	encoding := tagArray[0]
+	name := "unknown"
+	ctype := false
+	isTime := false
+	isDuration := false
+	isWktPointer := false
+	proto3 := false
+	validateUTF8 := true
+	for _, tag := range tagArray[3:] {
+		if strings.HasPrefix(tag, "name=") {
+			name = tag[5:]
+		}
+		if tag == "proto3" {
+			proto3 = true
+		}
+		if strings.HasPrefix(tag, "customtype=") {
+			ctype = true
+		}
+		if tag == "stdtime" {
+			isTime = true
+		}
+		if tag == "stdduration" {
+			isDuration = true
+		}
+		if tag == "wktptr" {
+			isWktPointer = true
+		}
+	}
+	validateUTF8 = validateUTF8 && proto3
+
+	// Figure out packaging (pointer, slice, or both)
+	slice := false
+	pointer := false
+	if t.Kind() == reflect.Slice && t.Elem().Kind() != reflect.Uint8 {
+		slice = true
+		t = t.Elem()
+	}
+	if t.Kind() == reflect.Ptr {
+		pointer = true
+		t = t.Elem()
+	}
+
+	if ctype {
+		if reflect.PtrTo(t).Implements(customType) {
+			if slice {
+				return makeUnmarshalCustomSlice(getUnmarshalInfo(t), name)
+			}
+			if pointer {
+				return makeUnmarshalCustomPtr(getUnmarshalInfo(t), name)
+			}
+			return makeUnmarshalCustom(getUnmarshalInfo(t), name)
+		} else {
+			panic(fmt.Sprintf("custom type: type: %v, does not implement the proto.custom interface", t))
+		}
+	}
+
+	if isTime {
+		if pointer {
+			if slice {
+				return makeUnmarshalTimePtrSlice(getUnmarshalInfo(t), name)
+			}
+			return makeUnmarshalTimePtr(getUnmarshalInfo(t), name)
+		}
+		if slice {
+			return makeUnmarshalTimeSlice(getUnmarshalInfo(t), name)
+		}
+		return makeUnmarshalTime(getUnmarshalInfo(t), name)
+	}
+
+	if isDuration {
+		if pointer {
+			if slice {
+				return makeUnmarshalDurationPtrSlice(getUnmarshalInfo(t), name)
+			}
+			return makeUnmarshalDurationPtr(getUnmarshalInfo(t), name)
+		}
+		if slice {
+			return makeUnmarshalDurationSlice(getUnmarshalInfo(t), name)
+		}
+		return makeUnmarshalDuration(getUnmarshalInfo(t), name)
+	}
+
+	if isWktPointer {
+		switch t.Kind() {
+		case reflect.Float64:
+			if pointer {
+				if slice {
+					return makeStdDoubleValuePtrSliceUnmarshaler(getUnmarshalInfo(t), name)
+				}
+				return makeStdDoubleValuePtrUnmarshaler(getUnmarshalInfo(t), name)
+			}
+			if slice {
+				return makeStdDoubleValueSliceUnmarshaler(getUnmarshalInfo(t), name)
+			}
+			return makeStdDoubleValueUnmarshaler(getUnmarshalInfo(t), name)
+		case reflect.Float32:
+			if pointer {
+				if slice {
+					return makeStdFloatValuePtrSliceUnmarshaler(getUnmarshalInfo(t), name)
+				}
+				return makeStdFloatValuePtrUnmarshaler(getUnmarshalInfo(t), name)
+			}
+			if slice {
+				return makeStdFloatValueSliceUnmarshaler(getUnmarshalInfo(t), name)
+			}
+			return makeStdFloatValueUnmarshaler(getUnmarshalInfo(t), name)
+		case reflect.Int64:
+			if pointer {
+				if slice {
+					return makeStdInt64ValuePtrSliceUnmarshaler(getUnmarshalInfo(t), name)
+				}
+				return makeStdInt64ValuePtrUnmarshaler(getUnmarshalInfo(t), name)
+			}
+			if slice {
+				return makeStdInt64ValueSliceUnmarshaler(getUnmarshalInfo(t), name)
+			}
+			return makeStdInt64ValueUnmarshaler(getUnmarshalInfo(t), name)
+		case reflect.Uint64:
+			if pointer {
+				if slice {
+					return makeStdUInt64ValuePtrSliceUnmarshaler(getUnmarshalInfo(t), name)
+				}
+				return makeStdUInt64ValuePtrUnmarshaler(getUnmarshalInfo(t), name)
+			}
+			if slice {
+				return makeStdUInt64ValueSliceUnmarshaler(getUnmarshalInfo(t), name)
+			}
+			return makeStdUInt64ValueUnmarshaler(getUnmarshalInfo(t), name)
+		case reflect.Int32:
+			if pointer {
+				if slice {
+					return makeStdInt32ValuePtrSliceUnmarshaler(getUnmarshalInfo(t), name)
+				}
+				return makeStdInt32ValuePtrUnmarshaler(getUnmarshalInfo(t), name)
+			}
+			if slice {
+				return makeStdInt32ValueSliceUnmarshaler(getUnmarshalInfo(t), name)
+			}
+			return makeStdInt32ValueUnmarshaler(getUnmarshalInfo(t), name)
+		case reflect.Uint32:
+			if pointer {
+				if slice {
+					return makeStdUInt32ValuePtrSliceUnmarshaler(getUnmarshalInfo(t), name)
+				}
+				return makeStdUInt32ValuePtrUnmarshaler(getUnmarshalInfo(t), name)
+			}
+			if slice {
+				return makeStdUInt32ValueSliceUnmarshaler(getUnmarshalInfo(t), name)
+			}
+			return makeStdUInt32ValueUnmarshaler(getUnmarshalInfo(t), name)
+		case reflect.Bool:
+			if pointer {
+				if slice {
+					return makeStdBoolValuePtrSliceUnmarshaler(getUnmarshalInfo(t), name)
+				}
+				return makeStdBoolValuePtrUnmarshaler(getUnmarshalInfo(t), name)
+			}
+			if slice {
+				return makeStdBoolValueSliceUnmarshaler(getUnmarshalInfo(t), name)
+			}
+			return makeStdBoolValueUnmarshaler(getUnmarshalInfo(t), name)
+		case reflect.String:
+			if pointer {
+				if slice {
+					return makeStdStringValuePtrSliceUnmarshaler(getUnmarshalInfo(t), name)
+				}
+				return makeStdStringValuePtrUnmarshaler(getUnmarshalInfo(t), name)
+			}
+			if slice {
+				return makeStdStringValueSliceUnmarshaler(getUnmarshalInfo(t), name)
+			}
+			return makeStdStringValueUnmarshaler(getUnmarshalInfo(t), name)
+		case uint8SliceType:
+			if pointer {
+				if slice {
+					return makeStdBytesValuePtrSliceUnmarshaler(getUnmarshalInfo(t), name)
+				}
+				return makeStdBytesValuePtrUnmarshaler(getUnmarshalInfo(t), name)
+			}
+			if slice {
+				return makeStdBytesValueSliceUnmarshaler(getUnmarshalInfo(t), name)
+			}
+			return makeStdBytesValueUnmarshaler(getUnmarshalInfo(t), name)
+		default:
+			panic(fmt.Sprintf("unknown wktpointer type %#v", t))
+		}
+	}
+
+	// We'll never have both pointer and slice for basic types.
+	if pointer && slice && t.Kind() != reflect.Struct {
+		panic("both pointer and slice for basic type in " + t.Name())
+	}
+
+	switch t.Kind() {
+	case reflect.Bool:
+		if pointer {
+			return unmarshalBoolPtr
+		}
+		if slice {
+			return unmarshalBoolSlice
+		}
+		return unmarshalBoolValue
+	case reflect.Int32:
+		switch encoding {
+		case "fixed32":
+			if pointer {
+				return unmarshalFixedS32Ptr
+			}
+			if slice {
+				return unmarshalFixedS32Slice
+			}
+			return unmarshalFixedS32Value
+		case "varint":
+			// this could be int32 or enum
+			if pointer {
+				return unmarshalInt32Ptr
+			}
+			if slice {
+				return unmarshalInt32Slice
+			}
+			return unmarshalInt32Value
+		case "zigzag32":
+			if pointer {
+				return unmarshalSint32Ptr
+			}
+			if slice {
+				return unmarshalSint32Slice
+			}
+			return unmarshalSint32Value
+		}
+	case reflect.Int64:
+		switch encoding {
+		case "fixed64":
+			if pointer {
+				return unmarshalFixedS64Ptr
+			}
+			if slice {
+				return unmarshalFixedS64Slice
+			}
+			return unmarshalFixedS64Value
+		case "varint":
+			if pointer {
+				return unmarshalInt64Ptr
+			}
+			if slice {
+				return unmarshalInt64Slice
+			}
+			return unmarshalInt64Value
+		case "zigzag64":
+			if pointer {
+				return unmarshalSint64Ptr
+			}
+			if slice {
+				return unmarshalSint64Slice
+			}
+			return unmarshalSint64Value
+		}
+	case reflect.Uint32:
+		switch encoding {
+		case "fixed32":
+			if pointer {
+				return unmarshalFixed32Ptr
+			}
+			if slice {
+				return unmarshalFixed32Slice
+			}
+			return unmarshalFixed32Value
+		case "varint":
+			if pointer {
+				return unmarshalUint32Ptr
+			}
+			if slice {
+				return unmarshalUint32Slice
+			}
+			return unmarshalUint32Value
+		}
+	case reflect.Uint64:
+		switch encoding {
+		case "fixed64":
+			if pointer {
+				return unmarshalFixed64Ptr
+			}
+			if slice {
+				return unmarshalFixed64Slice
+			}
+			return unmarshalFixed64Value
+		case "varint":
+			if pointer {
+				return unmarshalUint64Ptr
+			}
+			if slice {
+				return unmarshalUint64Slice
+			}
+			return unmarshalUint64Value
+		}
+	case reflect.Float32:
+		if pointer {
+			return unmarshalFloat32Ptr
+		}
+		if slice {
+			return unmarshalFloat32Slice
+		}
+		return unmarshalFloat32Value
+	case reflect.Float64:
+		if pointer {
+			return unmarshalFloat64Ptr
+		}
+		if slice {
+			return unmarshalFloat64Slice
+		}
+		return unmarshalFloat64Value
+	case reflect.Map:
+		panic("map type in typeUnmarshaler in " + t.Name())
+	case reflect.Slice:
+		if pointer {
+			panic("bad pointer in slice case in " + t.Name())
+		}
+		if slice {
+			return unmarshalBytesSlice
+		}
+		return unmarshalBytesValue
+	case reflect.String:
+		if validateUTF8 {
+			if pointer {
+				return unmarshalUTF8StringPtr
+			}
+			if slice {
+				return unmarshalUTF8StringSlice
+			}
+			return unmarshalUTF8StringValue
+		}
+		if pointer {
+			return unmarshalStringPtr
+		}
+		if slice {
+			return unmarshalStringSlice
+		}
+		return unmarshalStringValue
+	case reflect.Struct:
+		// message or group field
+		if !pointer {
+			switch encoding {
+			case "bytes":
+				if slice {
+					return makeUnmarshalMessageSlice(getUnmarshalInfo(t), name)
+				}
+				return makeUnmarshalMessage(getUnmarshalInfo(t), name)
+			}
+		}
+		switch encoding {
+		case "bytes":
+			if slice {
+				return makeUnmarshalMessageSlicePtr(getUnmarshalInfo(t), name)
+			}
+			return makeUnmarshalMessagePtr(getUnmarshalInfo(t), name)
+		case "group":
+			if slice {
+				return makeUnmarshalGroupSlicePtr(getUnmarshalInfo(t), name)
+			}
+			return makeUnmarshalGroupPtr(getUnmarshalInfo(t), name)
+		}
+	}
+	panic(fmt.Sprintf("unmarshaler not found type:%s encoding:%s", t, encoding))
+}
+
+// Below are all the unmarshalers for individual fields of various types.
+
+func unmarshalInt64Value(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireVarint {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	b = b[n:]
+	v := int64(x)
+	*f.toInt64() = v
+	return b, nil
+}
+
+func unmarshalInt64Ptr(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireVarint {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	b = b[n:]
+	v := int64(x)
+	*f.toInt64Ptr() = &v
+	return b, nil
+}
+
+func unmarshalInt64Slice(b []byte, f pointer, w int) ([]byte, error) {
+	if w == WireBytes { // packed
+		x, n := decodeVarint(b)
+		if n == 0 {
+			return nil, io.ErrUnexpectedEOF
+		}
+		b = b[n:]
+		if x > uint64(len(b)) {
+			return nil, io.ErrUnexpectedEOF
+		}
+		res := b[x:]
+		b = b[:x]
+		for len(b) > 0 {
+			x, n = decodeVarint(b)
+			if n == 0 {
+				return nil, io.ErrUnexpectedEOF
+			}
+			b = b[n:]
+			v := int64(x)
+			s := f.toInt64Slice()
+			*s = append(*s, v)
+		}
+		return res, nil
+	}
+	if w != WireVarint {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	b = b[n:]
+	v := int64(x)
+	s := f.toInt64Slice()
+	*s = append(*s, v)
+	return b, nil
+}
+
+func unmarshalSint64Value(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireVarint {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	b = b[n:]
+	v := int64(x>>1) ^ int64(x)<<63>>63
+	*f.toInt64() = v
+	return b, nil
+}
+
+func unmarshalSint64Ptr(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireVarint {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	b = b[n:]
+	v := int64(x>>1) ^ int64(x)<<63>>63
+	*f.toInt64Ptr() = &v
+	return b, nil
+}
+
+func unmarshalSint64Slice(b []byte, f pointer, w int) ([]byte, error) {
+	if w == WireBytes { // packed
+		x, n := decodeVarint(b)
+		if n == 0 {
+			return nil, io.ErrUnexpectedEOF
+		}
+		b = b[n:]
+		if x > uint64(len(b)) {
+			return nil, io.ErrUnexpectedEOF
+		}
+		res := b[x:]
+		b = b[:x]
+		for len(b) > 0 {
+			x, n = decodeVarint(b)
+			if n == 0 {
+				return nil, io.ErrUnexpectedEOF
+			}
+			b = b[n:]
+			v := int64(x>>1) ^ int64(x)<<63>>63
+			s := f.toInt64Slice()
+			*s = append(*s, v)
+		}
+		return res, nil
+	}
+	if w != WireVarint {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	b = b[n:]
+	v := int64(x>>1) ^ int64(x)<<63>>63
+	s := f.toInt64Slice()
+	*s = append(*s, v)
+	return b, nil
+}
+
+func unmarshalUint64Value(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireVarint {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	b = b[n:]
+	v := uint64(x)
+	*f.toUint64() = v
+	return b, nil
+}
+
+func unmarshalUint64Ptr(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireVarint {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	b = b[n:]
+	v := uint64(x)
+	*f.toUint64Ptr() = &v
+	return b, nil
+}
+
+func unmarshalUint64Slice(b []byte, f pointer, w int) ([]byte, error) {
+	if w == WireBytes { // packed
+		x, n := decodeVarint(b)
+		if n == 0 {
+			return nil, io.ErrUnexpectedEOF
+		}
+		b = b[n:]
+		if x > uint64(len(b)) {
+			return nil, io.ErrUnexpectedEOF
+		}
+		res := b[x:]
+		b = b[:x]
+		for len(b) > 0 {
+			x, n = decodeVarint(b)
+			if n == 0 {
+				return nil, io.ErrUnexpectedEOF
+			}
+			b = b[n:]
+			v := uint64(x)
+			s := f.toUint64Slice()
+			*s = append(*s, v)
+		}
+		return res, nil
+	}
+	if w != WireVarint {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	b = b[n:]
+	v := uint64(x)
+	s := f.toUint64Slice()
+	*s = append(*s, v)
+	return b, nil
+}
+
+func unmarshalInt32Value(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireVarint {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	b = b[n:]
+	v := int32(x)
+	*f.toInt32() = v
+	return b, nil
+}
+
+func unmarshalInt32Ptr(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireVarint {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	b = b[n:]
+	v := int32(x)
+	f.setInt32Ptr(v)
+	return b, nil
+}
+
+func unmarshalInt32Slice(b []byte, f pointer, w int) ([]byte, error) {
+	if w == WireBytes { // packed
+		x, n := decodeVarint(b)
+		if n == 0 {
+			return nil, io.ErrUnexpectedEOF
+		}
+		b = b[n:]
+		if x > uint64(len(b)) {
+			return nil, io.ErrUnexpectedEOF
+		}
+		res := b[x:]
+		b = b[:x]
+		for len(b) > 0 {
+			x, n = decodeVarint(b)
+			if n == 0 {
+				return nil, io.ErrUnexpectedEOF
+			}
+			b = b[n:]
+			v := int32(x)
+			f.appendInt32Slice(v)
+		}
+		return res, nil
+	}
+	if w != WireVarint {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	b = b[n:]
+	v := int32(x)
+	f.appendInt32Slice(v)
+	return b, nil
+}
+
+func unmarshalSint32Value(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireVarint {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	b = b[n:]
+	v := int32(x>>1) ^ int32(x)<<31>>31
+	*f.toInt32() = v
+	return b, nil
+}
+
+func unmarshalSint32Ptr(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireVarint {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	b = b[n:]
+	v := int32(x>>1) ^ int32(x)<<31>>31
+	f.setInt32Ptr(v)
+	return b, nil
+}
+
+func unmarshalSint32Slice(b []byte, f pointer, w int) ([]byte, error) {
+	if w == WireBytes { // packed
+		x, n := decodeVarint(b)
+		if n == 0 {
+			return nil, io.ErrUnexpectedEOF
+		}
+		b = b[n:]
+		if x > uint64(len(b)) {
+			return nil, io.ErrUnexpectedEOF
+		}
+		res := b[x:]
+		b = b[:x]
+		for len(b) > 0 {
+			x, n = decodeVarint(b)
+			if n == 0 {
+				return nil, io.ErrUnexpectedEOF
+			}
+			b = b[n:]
+			v := int32(x>>1) ^ int32(x)<<31>>31
+			f.appendInt32Slice(v)
+		}
+		return res, nil
+	}
+	if w != WireVarint {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	b = b[n:]
+	v := int32(x>>1) ^ int32(x)<<31>>31
+	f.appendInt32Slice(v)
+	return b, nil
+}
+
+func unmarshalUint32Value(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireVarint {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	b = b[n:]
+	v := uint32(x)
+	*f.toUint32() = v
+	return b, nil
+}
+
+func unmarshalUint32Ptr(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireVarint {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	b = b[n:]
+	v := uint32(x)
+	*f.toUint32Ptr() = &v
+	return b, nil
+}
+
+func unmarshalUint32Slice(b []byte, f pointer, w int) ([]byte, error) {
+	if w == WireBytes { // packed
+		x, n := decodeVarint(b)
+		if n == 0 {
+			return nil, io.ErrUnexpectedEOF
+		}
+		b = b[n:]
+		if x > uint64(len(b)) {
+			return nil, io.ErrUnexpectedEOF
+		}
+		res := b[x:]
+		b = b[:x]
+		for len(b) > 0 {
+			x, n = decodeVarint(b)
+			if n == 0 {
+				return nil, io.ErrUnexpectedEOF
+			}
+			b = b[n:]
+			v := uint32(x)
+			s := f.toUint32Slice()
+			*s = append(*s, v)
+		}
+		return res, nil
+	}
+	if w != WireVarint {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	b = b[n:]
+	v := uint32(x)
+	s := f.toUint32Slice()
+	*s = append(*s, v)
+	return b, nil
+}
+
+func unmarshalFixed64Value(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireFixed64 {
+		return b, errInternalBadWireType
+	}
+	if len(b) < 8 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := uint64(b[0]) | uint64(b[1])<<8 | uint64(b[2])<<16 | uint64(b[3])<<24 | uint64(b[4])<<32 | uint64(b[5])<<40 | uint64(b[6])<<48 | uint64(b[7])<<56
+	*f.toUint64() = v
+	return b[8:], nil
+}
+
+func unmarshalFixed64Ptr(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireFixed64 {
+		return b, errInternalBadWireType
+	}
+	if len(b) < 8 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := uint64(b[0]) | uint64(b[1])<<8 | uint64(b[2])<<16 | uint64(b[3])<<24 | uint64(b[4])<<32 | uint64(b[5])<<40 | uint64(b[6])<<48 | uint64(b[7])<<56
+	*f.toUint64Ptr() = &v
+	return b[8:], nil
+}
+
+func unmarshalFixed64Slice(b []byte, f pointer, w int) ([]byte, error) {
+	if w == WireBytes { // packed
+		x, n := decodeVarint(b)
+		if n == 0 {
+			return nil, io.ErrUnexpectedEOF
+		}
+		b = b[n:]
+		if x > uint64(len(b)) {
+			return nil, io.ErrUnexpectedEOF
+		}
+		res := b[x:]
+		b = b[:x]
+		for len(b) > 0 {
+			if len(b) < 8 {
+				return nil, io.ErrUnexpectedEOF
+			}
+			v := uint64(b[0]) | uint64(b[1])<<8 | uint64(b[2])<<16 | uint64(b[3])<<24 | uint64(b[4])<<32 | uint64(b[5])<<40 | uint64(b[6])<<48 | uint64(b[7])<<56
+			s := f.toUint64Slice()
+			*s = append(*s, v)
+			b = b[8:]
+		}
+		return res, nil
+	}
+	if w != WireFixed64 {
+		return b, errInternalBadWireType
+	}
+	if len(b) < 8 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := uint64(b[0]) | uint64(b[1])<<8 | uint64(b[2])<<16 | uint64(b[3])<<24 | uint64(b[4])<<32 | uint64(b[5])<<40 | uint64(b[6])<<48 | uint64(b[7])<<56
+	s := f.toUint64Slice()
+	*s = append(*s, v)
+	return b[8:], nil
+}
+
+func unmarshalFixedS64Value(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireFixed64 {
+		return b, errInternalBadWireType
+	}
+	if len(b) < 8 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := int64(b[0]) | int64(b[1])<<8 | int64(b[2])<<16 | int64(b[3])<<24 | int64(b[4])<<32 | int64(b[5])<<40 | int64(b[6])<<48 | int64(b[7])<<56
+	*f.toInt64() = v
+	return b[8:], nil
+}
+
+func unmarshalFixedS64Ptr(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireFixed64 {
+		return b, errInternalBadWireType
+	}
+	if len(b) < 8 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := int64(b[0]) | int64(b[1])<<8 | int64(b[2])<<16 | int64(b[3])<<24 | int64(b[4])<<32 | int64(b[5])<<40 | int64(b[6])<<48 | int64(b[7])<<56
+	*f.toInt64Ptr() = &v
+	return b[8:], nil
+}
+
+func unmarshalFixedS64Slice(b []byte, f pointer, w int) ([]byte, error) {
+	if w == WireBytes { // packed
+		x, n := decodeVarint(b)
+		if n == 0 {
+			return nil, io.ErrUnexpectedEOF
+		}
+		b = b[n:]
+		if x > uint64(len(b)) {
+			return nil, io.ErrUnexpectedEOF
+		}
+		res := b[x:]
+		b = b[:x]
+		for len(b) > 0 {
+			if len(b) < 8 {
+				return nil, io.ErrUnexpectedEOF
+			}
+			v := int64(b[0]) | int64(b[1])<<8 | int64(b[2])<<16 | int64(b[3])<<24 | int64(b[4])<<32 | int64(b[5])<<40 | int64(b[6])<<48 | int64(b[7])<<56
+			s := f.toInt64Slice()
+			*s = append(*s, v)
+			b = b[8:]
+		}
+		return res, nil
+	}
+	if w != WireFixed64 {
+		return b, errInternalBadWireType
+	}
+	if len(b) < 8 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := int64(b[0]) | int64(b[1])<<8 | int64(b[2])<<16 | int64(b[3])<<24 | int64(b[4])<<32 | int64(b[5])<<40 | int64(b[6])<<48 | int64(b[7])<<56
+	s := f.toInt64Slice()
+	*s = append(*s, v)
+	return b[8:], nil
+}
+
+func unmarshalFixed32Value(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireFixed32 {
+		return b, errInternalBadWireType
+	}
+	if len(b) < 4 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := uint32(b[0]) | uint32(b[1])<<8 | uint32(b[2])<<16 | uint32(b[3])<<24
+	*f.toUint32() = v
+	return b[4:], nil
+}
+
+func unmarshalFixed32Ptr(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireFixed32 {
+		return b, errInternalBadWireType
+	}
+	if len(b) < 4 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := uint32(b[0]) | uint32(b[1])<<8 | uint32(b[2])<<16 | uint32(b[3])<<24
+	*f.toUint32Ptr() = &v
+	return b[4:], nil
+}
+
+func unmarshalFixed32Slice(b []byte, f pointer, w int) ([]byte, error) {
+	if w == WireBytes { // packed
+		x, n := decodeVarint(b)
+		if n == 0 {
+			return nil, io.ErrUnexpectedEOF
+		}
+		b = b[n:]
+		if x > uint64(len(b)) {
+			return nil, io.ErrUnexpectedEOF
+		}
+		res := b[x:]
+		b = b[:x]
+		for len(b) > 0 {
+			if len(b) < 4 {
+				return nil, io.ErrUnexpectedEOF
+			}
+			v := uint32(b[0]) | uint32(b[1])<<8 | uint32(b[2])<<16 | uint32(b[3])<<24
+			s := f.toUint32Slice()
+			*s = append(*s, v)
+			b = b[4:]
+		}
+		return res, nil
+	}
+	if w != WireFixed32 {
+		return b, errInternalBadWireType
+	}
+	if len(b) < 4 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := uint32(b[0]) | uint32(b[1])<<8 | uint32(b[2])<<16 | uint32(b[3])<<24
+	s := f.toUint32Slice()
+	*s = append(*s, v)
+	return b[4:], nil
+}
+
+func unmarshalFixedS32Value(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireFixed32 {
+		return b, errInternalBadWireType
+	}
+	if len(b) < 4 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := int32(b[0]) | int32(b[1])<<8 | int32(b[2])<<16 | int32(b[3])<<24
+	*f.toInt32() = v
+	return b[4:], nil
+}
+
+func unmarshalFixedS32Ptr(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireFixed32 {
+		return b, errInternalBadWireType
+	}
+	if len(b) < 4 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := int32(b[0]) | int32(b[1])<<8 | int32(b[2])<<16 | int32(b[3])<<24
+	f.setInt32Ptr(v)
+	return b[4:], nil
+}
+
+func unmarshalFixedS32Slice(b []byte, f pointer, w int) ([]byte, error) {
+	if w == WireBytes { // packed
+		x, n := decodeVarint(b)
+		if n == 0 {
+			return nil, io.ErrUnexpectedEOF
+		}
+		b = b[n:]
+		if x > uint64(len(b)) {
+			return nil, io.ErrUnexpectedEOF
+		}
+		res := b[x:]
+		b = b[:x]
+		for len(b) > 0 {
+			if len(b) < 4 {
+				return nil, io.ErrUnexpectedEOF
+			}
+			v := int32(b[0]) | int32(b[1])<<8 | int32(b[2])<<16 | int32(b[3])<<24
+			f.appendInt32Slice(v)
+			b = b[4:]
+		}
+		return res, nil
+	}
+	if w != WireFixed32 {
+		return b, errInternalBadWireType
+	}
+	if len(b) < 4 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := int32(b[0]) | int32(b[1])<<8 | int32(b[2])<<16 | int32(b[3])<<24
+	f.appendInt32Slice(v)
+	return b[4:], nil
+}
+
+func unmarshalBoolValue(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireVarint {
+		return b, errInternalBadWireType
+	}
+	// Note: any length varint is allowed, even though any sane
+	// encoder will use one byte.
+	// See https://github.com/golang/protobuf/issues/76
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	// TODO: check if x>1? Tests seem to indicate no.
+	v := x != 0
+	*f.toBool() = v
+	return b[n:], nil
+}
+
+func unmarshalBoolPtr(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireVarint {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := x != 0
+	*f.toBoolPtr() = &v
+	return b[n:], nil
+}
+
+func unmarshalBoolSlice(b []byte, f pointer, w int) ([]byte, error) {
+	if w == WireBytes { // packed
+		x, n := decodeVarint(b)
+		if n == 0 {
+			return nil, io.ErrUnexpectedEOF
+		}
+		b = b[n:]
+		if x > uint64(len(b)) {
+			return nil, io.ErrUnexpectedEOF
+		}
+		res := b[x:]
+		b = b[:x]
+		for len(b) > 0 {
+			x, n = decodeVarint(b)
+			if n == 0 {
+				return nil, io.ErrUnexpectedEOF
+			}
+			v := x != 0
+			s := f.toBoolSlice()
+			*s = append(*s, v)
+			b = b[n:]
+		}
+		return res, nil
+	}
+	if w != WireVarint {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := x != 0
+	s := f.toBoolSlice()
+	*s = append(*s, v)
+	return b[n:], nil
+}
+
+func unmarshalFloat64Value(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireFixed64 {
+		return b, errInternalBadWireType
+	}
+	if len(b) < 8 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := math.Float64frombits(uint64(b[0]) | uint64(b[1])<<8 | uint64(b[2])<<16 | uint64(b[3])<<24 | uint64(b[4])<<32 | uint64(b[5])<<40 | uint64(b[6])<<48 | uint64(b[7])<<56)
+	*f.toFloat64() = v
+	return b[8:], nil
+}
+
+func unmarshalFloat64Ptr(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireFixed64 {
+		return b, errInternalBadWireType
+	}
+	if len(b) < 8 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := math.Float64frombits(uint64(b[0]) | uint64(b[1])<<8 | uint64(b[2])<<16 | uint64(b[3])<<24 | uint64(b[4])<<32 | uint64(b[5])<<40 | uint64(b[6])<<48 | uint64(b[7])<<56)
+	*f.toFloat64Ptr() = &v
+	return b[8:], nil
+}
+
+func unmarshalFloat64Slice(b []byte, f pointer, w int) ([]byte, error) {
+	if w == WireBytes { // packed
+		x, n := decodeVarint(b)
+		if n == 0 {
+			return nil, io.ErrUnexpectedEOF
+		}
+		b = b[n:]
+		if x > uint64(len(b)) {
+			return nil, io.ErrUnexpectedEOF
+		}
+		res := b[x:]
+		b = b[:x]
+		for len(b) > 0 {
+			if len(b) < 8 {
+				return nil, io.ErrUnexpectedEOF
+			}
+			v := math.Float64frombits(uint64(b[0]) | uint64(b[1])<<8 | uint64(b[2])<<16 | uint64(b[3])<<24 | uint64(b[4])<<32 | uint64(b[5])<<40 | uint64(b[6])<<48 | uint64(b[7])<<56)
+			s := f.toFloat64Slice()
+			*s = append(*s, v)
+			b = b[8:]
+		}
+		return res, nil
+	}
+	if w != WireFixed64 {
+		return b, errInternalBadWireType
+	}
+	if len(b) < 8 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := math.Float64frombits(uint64(b[0]) | uint64(b[1])<<8 | uint64(b[2])<<16 | uint64(b[3])<<24 | uint64(b[4])<<32 | uint64(b[5])<<40 | uint64(b[6])<<48 | uint64(b[7])<<56)
+	s := f.toFloat64Slice()
+	*s = append(*s, v)
+	return b[8:], nil
+}
+
+func unmarshalFloat32Value(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireFixed32 {
+		return b, errInternalBadWireType
+	}
+	if len(b) < 4 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := math.Float32frombits(uint32(b[0]) | uint32(b[1])<<8 | uint32(b[2])<<16 | uint32(b[3])<<24)
+	*f.toFloat32() = v
+	return b[4:], nil
+}
+
+func unmarshalFloat32Ptr(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireFixed32 {
+		return b, errInternalBadWireType
+	}
+	if len(b) < 4 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := math.Float32frombits(uint32(b[0]) | uint32(b[1])<<8 | uint32(b[2])<<16 | uint32(b[3])<<24)
+	*f.toFloat32Ptr() = &v
+	return b[4:], nil
+}
+
+func unmarshalFloat32Slice(b []byte, f pointer, w int) ([]byte, error) {
+	if w == WireBytes { // packed
+		x, n := decodeVarint(b)
+		if n == 0 {
+			return nil, io.ErrUnexpectedEOF
+		}
+		b = b[n:]
+		if x > uint64(len(b)) {
+			return nil, io.ErrUnexpectedEOF
+		}
+		res := b[x:]
+		b = b[:x]
+		for len(b) > 0 {
+			if len(b) < 4 {
+				return nil, io.ErrUnexpectedEOF
+			}
+			v := math.Float32frombits(uint32(b[0]) | uint32(b[1])<<8 | uint32(b[2])<<16 | uint32(b[3])<<24)
+			s := f.toFloat32Slice()
+			*s = append(*s, v)
+			b = b[4:]
+		}
+		return res, nil
+	}
+	if w != WireFixed32 {
+		return b, errInternalBadWireType
+	}
+	if len(b) < 4 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := math.Float32frombits(uint32(b[0]) | uint32(b[1])<<8 | uint32(b[2])<<16 | uint32(b[3])<<24)
+	s := f.toFloat32Slice()
+	*s = append(*s, v)
+	return b[4:], nil
+}
+
+func unmarshalStringValue(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireBytes {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	b = b[n:]
+	if x > uint64(len(b)) {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := string(b[:x])
+	*f.toString() = v
+	return b[x:], nil
+}
+
+func unmarshalStringPtr(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireBytes {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	b = b[n:]
+	if x > uint64(len(b)) {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := string(b[:x])
+	*f.toStringPtr() = &v
+	return b[x:], nil
+}
+
+func unmarshalStringSlice(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireBytes {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	b = b[n:]
+	if x > uint64(len(b)) {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := string(b[:x])
+	s := f.toStringSlice()
+	*s = append(*s, v)
+	return b[x:], nil
+}
+
+func unmarshalUTF8StringValue(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireBytes {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	b = b[n:]
+	if x > uint64(len(b)) {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := string(b[:x])
+	*f.toString() = v
+	if !utf8.ValidString(v) {
+		return b[x:], errInvalidUTF8
+	}
+	return b[x:], nil
+}
+
+func unmarshalUTF8StringPtr(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireBytes {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	b = b[n:]
+	if x > uint64(len(b)) {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := string(b[:x])
+	*f.toStringPtr() = &v
+	if !utf8.ValidString(v) {
+		return b[x:], errInvalidUTF8
+	}
+	return b[x:], nil
+}
+
+func unmarshalUTF8StringSlice(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireBytes {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	b = b[n:]
+	if x > uint64(len(b)) {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := string(b[:x])
+	s := f.toStringSlice()
+	*s = append(*s, v)
+	if !utf8.ValidString(v) {
+		return b[x:], errInvalidUTF8
+	}
+	return b[x:], nil
+}
+
+var emptyBuf [0]byte
+
+func unmarshalBytesValue(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireBytes {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	b = b[n:]
+	if x > uint64(len(b)) {
+		return nil, io.ErrUnexpectedEOF
+	}
+	// The use of append here is a trick which avoids the zeroing
+	// that would be required if we used a make/copy pair.
+	// We append to emptyBuf instead of nil because we want
+	// a non-nil result even when the length is 0.
+	v := append(emptyBuf[:], b[:x]...)
+	*f.toBytes() = v
+	return b[x:], nil
+}
+
+func unmarshalBytesSlice(b []byte, f pointer, w int) ([]byte, error) {
+	if w != WireBytes {
+		return b, errInternalBadWireType
+	}
+	x, n := decodeVarint(b)
+	if n == 0 {
+		return nil, io.ErrUnexpectedEOF
+	}
+	b = b[n:]
+	if x > uint64(len(b)) {
+		return nil, io.ErrUnexpectedEOF
+	}
+	v := append(emptyBuf[:], b[:x]...)
+	s := f.toBytesSlice()
+	*s = append(*s, v)
+	return b[x:], nil
+}
+
+func makeUnmarshalMessagePtr(sub *unmarshalInfo, name string) unmarshaler {
+	return func(b []byte, f pointer, w int) ([]byte, error) {
+		if w != WireBytes {
+			return b, errInternalBadWireType
+		}
+		x, n := decodeVarint(b)
+		if n == 0 {
+			return nil, io.ErrUnexpectedEOF
+		}
+		b = b[n:]
+		if x > uint64(len(b)) {
+			return nil, io.ErrUnexpectedEOF
+		}
+		// First read the message field to see if something is there.
+		// The semantics of multiple submessages are weird.  Instead of
+		// the last one winning (as it is for all other fields), multiple
+		// submessages are merged.
+		v := f.getPointer()
+		if v.isNil() {
+			v = valToPointer(reflect.New(sub.typ))
+			f.setPointer(v)
+		}
+		err := sub.unmarshal(v, b[:x])
+		if err != nil {
+			if r, ok := err.(*RequiredNotSetError); ok {
+				r.field = name + "." + r.field
+			} else {
+				return nil, err
+			}
+		}
+		return b[x:], err
+	}
+}
+
+func makeUnmarshalMessageSlicePtr(sub *unmarshalInfo, name string) unmarshaler {
+	return func(b []byte, f pointer, w int) ([]byte, error) {
+		if w != WireBytes {
+			return b, errInternalBadWireType
+		}
+		x, n := decodeVarint(b)
+		if n == 0 {
+			return nil, io.ErrUnexpectedEOF
+		}
+		b = b[n:]
+		if x > uint64(len(b)) {
+			return nil, io.ErrUnexpectedEOF
+		}
+		v := valToPointer(reflect.New(sub.typ))
+		err := sub.unmarshal(v, b[:x])
+		if err != nil {
+			if r, ok := err.(*RequiredNotSetError); ok {
+				r.field = name + "." + r.field
+			} else {
+				return nil, err
+			}
+		}
+		f.appendPointer(v)
+		return b[x:], err
+	}
+}
+
+func makeUnmarshalGroupPtr(sub *unmarshalInfo, name string) unmarshaler {
+	return func(b []byte, f pointer, w int) ([]byte, error) {
+		if w != WireStartGroup {
+			return b, errInternalBadWireType
+		}
+		x, y := findEndGroup(b)
+		if x < 0 {
+			return nil, io.ErrUnexpectedEOF
+		}
+		v := f.getPointer()
+		if v.isNil() {
+			v = valToPointer(reflect.New(sub.typ))
+			f.setPointer(v)
+		}
+		err := sub.unmarshal(v, b[:x])
+		if err != nil {
+			if r, ok := err.(*RequiredNotSetError); ok {
+				r.field = name + "." + r.field
+			} else {
+				return nil, err
+			}
+		}
+		return b[y:], err
+	}
+}
+
+func makeUnmarshalGroupSlicePtr(sub *unmarshalInfo, name string) unmarshaler {
+	return func(b []byte, f pointer, w int) ([]byte, error) {
+		if w != WireStartGroup {
+			return b, errInternalBadWireType
+		}
+		x, y := findEndGroup(b)
+		if x < 0 {
+			return nil, io.ErrUnexpectedEOF
+		}
+		v := valToPointer(reflect.New(sub.typ))
+		err := sub.unmarshal(v, b[:x])
+		if err != nil {
+			if r, ok := err.(*RequiredNotSetError); ok {
+				r.field = name + "." + r.field
+			} else {
+				return nil, err
+			}
+		}
+		f.appendPointer(v)
+		return b[y:], err
+	}
+}
+
+func makeUnmarshalMap(f *reflect.StructField) unmarshaler {
+	t := f.Type
+	kt := t.Key()
+	vt := t.Elem()
+	tagArray := strings.Split(f.Tag.Get("protobuf"), ",")
+	valTags := strings.Split(f.Tag.Get("protobuf_val"), ",")
+	for _, t := range tagArray {
+		if strings.HasPrefix(t, "customtype=") {
+			valTags = append(valTags, t)
+		}
+		if t == "stdtime" {
+			valTags = append(valTags, t)
+		}
+		if t == "stdduration" {
+			valTags = append(valTags, t)
+		}
+		if t == "wktptr" {
+			valTags = append(valTags, t)
+		}
+	}
+	unmarshalKey := typeUnmarshaler(kt, f.Tag.Get("protobuf_key"))
+	unmarshalVal := typeUnmarshaler(vt, strings.Join(valTags, ","))
+	return func(b []byte, f pointer, w int) ([]byte, error) {
+		// The map entry is a submessage. Figure out how big it is.
+		if w != WireBytes {
+			return nil, fmt.Errorf("proto: bad wiretype for map field: got %d want %d", w, WireBytes)
+		}
+		x, n := decodeVarint(b)
+		if n == 0 {
+			return nil, io.ErrUnexpectedEOF
+		}
+		b = b[n:]
+		if x > uint64(len(b)) {
+			return nil, io.ErrUnexpectedEOF
+		}
+		r := b[x:] // unused data to return
+		b = b[:x]  // data for map entry
+
+		// Note: we could use #keys * #values ~= 200 functions
+		// to do map decoding without reflection. Probably not worth it.
+		// Maps will be somewhat slow. Oh well.
+
+		// Read key and value from data.
+		var nerr nonFatal
+		k := reflect.New(kt)
+		v := reflect.New(vt)
+		for len(b) > 0 {
+			x, n := decodeVarint(b)
+			if n == 0 {
+				return nil, io.ErrUnexpectedEOF
+			}
+			wire := int(x) & 7
+			b = b[n:]
+
+			var err error
+			switch x >> 3 {
+			case 1:
+				b, err = unmarshalKey(b, valToPointer(k), wire)
+			case 2:
+				b, err = unmarshalVal(b, valToPointer(v), wire)
+			default:
+				err = errInternalBadWireType // skip unknown tag
+			}
+
+			if nerr.Merge(err) {
+				continue
+			}
+			if err != errInternalBadWireType {
+				return nil, err
+			}
+
+			// Skip past unknown fields.
+			b, err = skipField(b, wire)
+			if err != nil {
+				return nil, err
+			}
+		}
+
+		// Get map, allocate if needed.
+		m := f.asPointerTo(t).Elem() // an addressable map[K]T
+		if m.IsNil() {
+			m.Set(reflect.MakeMap(t))
+		}
+
+		// Insert into map.
+		m.SetMapIndex(k.Elem(), v.Elem())
+
+		return r, nerr.E
+	}
+}
+
+// makeUnmarshalOneof makes an unmarshaler for oneof fields.
+// for:
+// message Msg {
+//   oneof F {
+//     int64 X = 1;
+//     float64 Y = 2;
+//   }
+// }
+// typ is the type of the concrete entry for a oneof case (e.g. Msg_X).
+// ityp is the interface type of the oneof field (e.g. isMsg_F).
+// unmarshal is the unmarshaler for the base type of the oneof case (e.g. int64).
+// Note that this function will be called once for each case in the oneof.
+func makeUnmarshalOneof(typ, ityp reflect.Type, unmarshal unmarshaler) unmarshaler {
+	sf := typ.Field(0)
+	field0 := toField(&sf)
+	return func(b []byte, f pointer, w int) ([]byte, error) {
+		// Allocate holder for value.
+		v := reflect.New(typ)
+
+		// Unmarshal data into holder.
+		// We unmarshal into the first field of the holder object.
+		var err error
+		var nerr nonFatal
+		b, err = unmarshal(b, valToPointer(v).offset(field0), w)
+		if !nerr.Merge(err) {
+			return nil, err
+		}
+
+		// Write pointer to holder into target field.
+		f.asPointerTo(ityp).Elem().Set(v)
+
+		return b, nerr.E
+	}
+}
+
+// Error used by decode internally.
+var errInternalBadWireType = errors.New("proto: internal error: bad wiretype")
+
+// skipField skips past a field of type wire and returns the remaining bytes.
+func skipField(b []byte, wire int) ([]byte, error) {
+	switch wire {
+	case WireVarint:
+		_, k := decodeVarint(b)
+		if k == 0 {
+			return b, io.ErrUnexpectedEOF
+		}
+		b = b[k:]
+	case WireFixed32:
+		if len(b) < 4 {
+			return b, io.ErrUnexpectedEOF
+		}
+		b = b[4:]
+	case WireFixed64:
+		if len(b) < 8 {
+			return b, io.ErrUnexpectedEOF
+		}
+		b = b[8:]
+	case WireBytes:
+		m, k := decodeVarint(b)
+		if k == 0 || uint64(len(b)-k) < m {
+			return b, io.ErrUnexpectedEOF
+		}
+		b = b[uint64(k)+m:]
+	case WireStartGroup:
+		_, i := findEndGroup(b)
+		if i == -1 {
+			return b, io.ErrUnexpectedEOF
+		}
+		b = b[i:]
+	default:
+		return b, fmt.Errorf("proto: can't skip unknown wire type %d", wire)
+	}
+	return b, nil
+}
+
+// findEndGroup finds the index of the next EndGroup tag.
+// Groups may be nested, so the "next" EndGroup tag is the first
+// unpaired EndGroup.
+// findEndGroup returns the indexes of the start and end of the EndGroup tag.
+// Returns (-1,-1) if it can't find one.
+func findEndGroup(b []byte) (int, int) {
+	depth := 1
+	i := 0
+	for {
+		x, n := decodeVarint(b[i:])
+		if n == 0 {
+			return -1, -1
+		}
+		j := i
+		i += n
+		switch x & 7 {
+		case WireVarint:
+			_, k := decodeVarint(b[i:])
+			if k == 0 {
+				return -1, -1
+			}
+			i += k
+		case WireFixed32:
+			if len(b)-4 < i {
+				return -1, -1
+			}
+			i += 4
+		case WireFixed64:
+			if len(b)-8 < i {
+				return -1, -1
+			}
+			i += 8
+		case WireBytes:
+			m, k := decodeVarint(b[i:])
+			if k == 0 {
+				return -1, -1
+			}
+			i += k
+			if uint64(len(b)-i) < m {
+				return -1, -1
+			}
+			i += int(m)
+		case WireStartGroup:
+			depth++
+		case WireEndGroup:
+			depth--
+			if depth == 0 {
+				return j, i
+			}
+		default:
+			return -1, -1
+		}
+	}
+}
+
+// encodeVarint appends a varint-encoded integer to b and returns the result.
+func encodeVarint(b []byte, x uint64) []byte {
+	for x >= 1<<7 {
+		b = append(b, byte(x&0x7f|0x80))
+		x >>= 7
+	}
+	return append(b, byte(x))
+}
+
+// decodeVarint reads a varint-encoded integer from b.
+// Returns the decoded integer and the number of bytes read.
+// If there is an error, it returns 0,0.
+func decodeVarint(b []byte) (uint64, int) {
+	var x, y uint64
+	if len(b) == 0 {
+		goto bad
+	}
+	x = uint64(b[0])
+	if x < 0x80 {
+		return x, 1
+	}
+	x -= 0x80
+
+	if len(b) <= 1 {
+		goto bad
+	}
+	y = uint64(b[1])
+	x += y << 7
+	if y < 0x80 {
+		return x, 2
+	}
+	x -= 0x80 << 7
+
+	if len(b) <= 2 {
+		goto bad
+	}
+	y = uint64(b[2])
+	x += y << 14
+	if y < 0x80 {
+		return x, 3
+	}
+	x -= 0x80 << 14
+
+	if len(b) <= 3 {
+		goto bad
+	}
+	y = uint64(b[3])
+	x += y << 21
+	if y < 0x80 {
+		return x, 4
+	}
+	x -= 0x80 << 21
+
+	if len(b) <= 4 {
+		goto bad
+	}
+	y = uint64(b[4])
+	x += y << 28
+	if y < 0x80 {
+		return x, 5
+	}
+	x -= 0x80 << 28
+
+	if len(b) <= 5 {
+		goto bad
+	}
+	y = uint64(b[5])
+	x += y << 35
+	if y < 0x80 {
+		return x, 6
+	}
+	x -= 0x80 << 35
+
+	if len(b) <= 6 {
+		goto bad
+	}
+	y = uint64(b[6])
+	x += y << 42
+	if y < 0x80 {
+		return x, 7
+	}
+	x -= 0x80 << 42
+
+	if len(b) <= 7 {
+		goto bad
+	}
+	y = uint64(b[7])
+	x += y << 49
+	if y < 0x80 {
+		return x, 8
+	}
+	x -= 0x80 << 49
+
+	if len(b) <= 8 {
+		goto bad
+	}
+	y = uint64(b[8])
+	x += y << 56
+	if y < 0x80 {
+		return x, 9
+	}
+	x -= 0x80 << 56
+
+	if len(b) <= 9 {
+		goto bad
+	}
+	y = uint64(b[9])
+	x += y << 63
+	if y < 2 {
+		return x, 10
+	}
+
+bad:
+	return 0, 0
+}