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[bytom/vapor.git] / vendor / github.com / gogo / protobuf / proto / table_unmarshal.go
diff --git a/vendor/github.com/gogo/protobuf/proto/table_unmarshal.go b/vendor/github.com/gogo/protobuf/proto/table_unmarshal.go
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+// 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
+}