Merge branch 'go-hello-world' into 'master'

Add hello-world Go executable and gitaly-proto 0.5.0

Closes gitaly#186

See merge request !127

.gitignore

@@ -11,3 +11,5 @@ tags
 .bundle/
 custom_hooks
 hooks/*.d
+/go_build
+/bin/hello-world

.gitlab-ci.yml

 image: "ruby:2.3"
 before_script:
-  - export PATH=~/bin:/usr/local/bin:/usr/bin:/bin:/usr/sbin:/sbin
+  - export PATH=~/bin:/usr/local/bin:/usr/bin:/bin:/usr/sbin:/sbin:/usr/local/go/bin
   - apt update
   - apt install rsync -y
   - gem install --bindir /usr/local/bin bundler
@@ -43,3 +43,12 @@ rspec:ruby2.1:
     - ruby
   except:
     - tags
+
+compile:
+  # Image taken from gitlab-ce@59f81b4ff8
+  image: "dev.gitlab.org:5005/gitlab/gitlab-build-images:ruby-2.3.3-golang-1.8-git-2.7-phantomjs-2.1-node-7.1"
+  script:
+    - go version
+    - which go
+    - bin/compile
+

README.md

@@ -66,9 +66,12 @@ make
 sudo make install
 ```
+To install gitlab-shell you also need a Go compiler version 1.5 or newer. https://golang.org/dl/
+
 ## Setup
     ./bin/install
+    ./bin/compile
 ## Check

bin/compile

+#!/usr/bin/env ruby
+
+require 'fileutils'
+
+# This will set the ROOT_PATH variable
+require_relative '../lib/gitlab_init'
+
+GO_DIR = 'go'
+BUILD_DIR = File.join(ROOT_PATH, 'go_build')
+GO_PACKAGE = File.join('gitlab.com/gitlab-org/gitlab-shell', GO_DIR)
+
+def main
+  FileUtils.rm_rf(BUILD_DIR)
+  build_source_dir = File.join(BUILD_DIR, 'src', GO_PACKAGE)
+  FileUtils.mkdir_p(build_source_dir)
+  FileUtils.cp_r(File.join(ROOT_PATH, GO_DIR, '.'), build_source_dir)
+  env = {
+    'GOPATH' => BUILD_DIR,
+    'GO15VENDOREXPERIMENT' => '1',
+  }
+  run!(env, %W[go install #{GO_PACKAGE}/cmd/...])
+  executables = Dir[File.join(BUILD_DIR, 'bin', '*')]
+  FileUtils.chmod(0755, executables)
+  FileUtils.cp(executables, File.join(ROOT_PATH, 'bin'))
+end
+
+def run!(env, cmd)
+  raise "env must be a hash" unless env.is_a?(Hash)
+  raise "cmd must be an array" unless cmd.is_a?(Array)
+
+  if !system(env, *cmd)
+    abort "command failed: #{env.inspect} #{cmd.join(' ')}"
+  end
+end
+
+main

go/README.md

+# Go executables for gitlab-shell
+
+This directory contains Go executables for use in gitlab-shell. To add
+a new command `foobar` create a subdirectory `cmd/foobar` and put your
+code in `package main` under `cmd/foobar`. This will automatically get
+compiled into `bin/foobar` by `../bin/compile`.

go/cmd/hello-world/main.go

+package main
+
+import (
+	"fmt"
+
+	// Example import, just to see if govendor is working for us
+	_ "gitlab.com/gitlab-org/gitaly-proto/go"
+)
+
+func main() {
+	fmt.Println("Hello, world!")
+}

go/vendor/github.com/golang/protobuf/LICENSE

+Go support for Protocol Buffers - Google's data interchange format
+
+Copyright 2010 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.
+

go/vendor/github.com/golang/protobuf/proto/Makefile

+# Go support for Protocol Buffers - Google's data interchange format
+#
+# Copyright 2010 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.
+
+install:
+	go install
+
+test: install generate-test-pbs
+	go test
+
+
+generate-test-pbs:
+	make install
+	make -C testdata
+	protoc --go_out=Mtestdata/test.proto=github.com/golang/protobuf/proto/testdata,Mgoogle/protobuf/any.proto=github.com/golang/protobuf/ptypes/any:. proto3_proto/proto3.proto
+	make

go/vendor/github.com/golang/protobuf/proto/clone.go

+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2011 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.
+
+// Protocol buffer deep copy and merge.
+// TODO: RawMessage.
+
+package proto
+
+import (
+	"log"
+	"reflect"
+	"strings"
+)
+
+// Clone returns a deep copy of a protocol buffer.
+func Clone(pb Message) Message {
+	in := reflect.ValueOf(pb)
+	if in.IsNil() {
+		return pb
+	}
+
+	out := reflect.New(in.Type().Elem())
+	// out is empty so a merge is a deep copy.
+	mergeStruct(out.Elem(), in.Elem())
+	return out.Interface().(Message)
+}
+
+// Merge merges src into dst.
+// Required and optional fields that are set in src will be set to that value in dst.
+// Elements of repeated fields will be appended.
+// Merge panics if src and dst are not the same type, or if dst is nil.
+func Merge(dst, src Message) {
+	in := reflect.ValueOf(src)
+	out := reflect.ValueOf(dst)
+	if out.IsNil() {
+		panic("proto: nil destination")
+	}
+	if in.Type() != out.Type() {
+		// Explicit test prior to mergeStruct so that mistyped nils will fail
+		panic("proto: type mismatch")
+	}
+	if in.IsNil() {
+		// Merging nil into non-nil is a quiet no-op
+		return
+	}
+	mergeStruct(out.Elem(), in.Elem())
+}
+
+func mergeStruct(out, in reflect.Value) {
+	sprop := GetProperties(in.Type())
+	for i := 0; i < in.NumField(); i++ {
+		f := in.Type().Field(i)
+		if strings.HasPrefix(f.Name, "XXX_") {
+			continue
+		}
+		mergeAny(out.Field(i), in.Field(i), false, sprop.Prop[i])
+	}
+
+	if emIn, ok := extendable(in.Addr().Interface()); ok {
+		emOut, _ := extendable(out.Addr().Interface())
+		mIn, muIn := emIn.extensionsRead()
+		if mIn != nil {
+			mOut := emOut.extensionsWrite()
+			muIn.Lock()
+			mergeExtension(mOut, mIn)
+			muIn.Unlock()
+		}
+	}
+
+	uf := in.FieldByName("XXX_unrecognized")
+	if !uf.IsValid() {
+		return
+	}
+	uin := uf.Bytes()
+	if len(uin) > 0 {
+		out.FieldByName("XXX_unrecognized").SetBytes(append([]byte(nil), uin...))
+	}
+}
+
+// mergeAny performs a merge between two values of the same type.
+// viaPtr indicates whether the values were indirected through a pointer (implying proto2).
+// prop is set if this is a struct field (it may be nil).
+func mergeAny(out, in reflect.Value, viaPtr bool, prop *Properties) {
+	if in.Type() == protoMessageType {
+		if !in.IsNil() {
+			if out.IsNil() {
+				out.Set(reflect.ValueOf(Clone(in.Interface().(Message))))
+			} else {
+				Merge(out.Interface().(Message), in.Interface().(Message))
+			}
+		}
+		return
+	}
+	switch in.Kind() {
+	case reflect.Bool, reflect.Float32, reflect.Float64, reflect.Int32, reflect.Int64,
+		reflect.String, reflect.Uint32, reflect.Uint64:
+		if !viaPtr && isProto3Zero(in) {
+			return
+		}
+		out.Set(in)
+	case reflect.Interface:
+		// Probably a oneof field; copy non-nil values.
+		if in.IsNil() {
+			return
+		}
+		// Allocate destination if it is not set, or set to a different type.
+		// Otherwise we will merge as normal.
+		if out.IsNil() || out.Elem().Type() != in.Elem().Type() {
+			out.Set(reflect.New(in.Elem().Elem().Type())) // interface -> *T -> T -> new(T)
+		}
+		mergeAny(out.Elem(), in.Elem(), false, nil)
+	case reflect.Map:
+		if in.Len() == 0 {
+			return
+		}
+		if out.IsNil() {
+			out.Set(reflect.MakeMap(in.Type()))
+		}
+		// For maps with value types of *T or []byte we need to deep copy each value.
+		elemKind := in.Type().Elem().Kind()
+		for _, key := range in.MapKeys() {
+			var val reflect.Value
+			switch elemKind {
+			case reflect.Ptr:
+				val = reflect.New(in.Type().Elem().Elem())
+				mergeAny(val, in.MapIndex(key), false, nil)
+			case reflect.Slice:
+				val = in.MapIndex(key)
+				val = reflect.ValueOf(append([]byte{}, val.Bytes()...))
+			default:
+				val = in.MapIndex(key)
+			}
+			out.SetMapIndex(key, val)
+		}
+	case reflect.Ptr:
+		if in.IsNil() {
+			return
+		}
+		if out.IsNil() {
+			out.Set(reflect.New(in.Elem().Type()))
+		}
+		mergeAny(out.Elem(), in.Elem(), true, nil)
+	case reflect.Slice:
+		if in.IsNil() {
+			return
+		}
+		if in.Type().Elem().Kind() == reflect.Uint8 {
+			// []byte is a scalar bytes field, not a repeated field.
+
+			// Edge case: if this is in a proto3 message, a zero length
+			// bytes field is considered the zero value, and should not
+			// be merged.
+			if prop != nil && prop.proto3 && in.Len() == 0 {
+				return
+			}
+
+			// Make a deep copy.
+			// Append to []byte{} instead of []byte(nil) so that we never end up
+			// with a nil result.
+			out.SetBytes(append([]byte{}, in.Bytes()...))
+			return
+		}
+		n := in.Len()
+		if out.IsNil() {
+			out.Set(reflect.MakeSlice(in.Type(), 0, n))
+		}
+		switch in.Type().Elem().Kind() {
+		case reflect.Bool, reflect.Float32, reflect.Float64, reflect.Int32, reflect.Int64,
+			reflect.String, reflect.Uint32, reflect.Uint64:
+			out.Set(reflect.AppendSlice(out, in))
+		default:
+			for i := 0; i < n; i++ {
+				x := reflect.Indirect(reflect.New(in.Type().Elem()))
+				mergeAny(x, in.Index(i), false, nil)
+				out.Set(reflect.Append(out, x))
+			}
+		}
+	case reflect.Struct:
+		mergeStruct(out, in)
+	default:
+		// unknown type, so not a protocol buffer
+		log.Printf("proto: don't know how to copy %v", in)
+	}
+}
+
+func mergeExtension(out, in map[int32]Extension) {
+	for extNum, eIn := range in {
+		eOut := Extension{desc: eIn.desc}
+		if eIn.value != nil {
+			v := reflect.New(reflect.TypeOf(eIn.value)).Elem()
+			mergeAny(v, reflect.ValueOf(eIn.value), false, nil)
+			eOut.value = v.Interface()
+		}
+		if eIn.enc != nil {
+			eOut.enc = make([]byte, len(eIn.enc))
+			copy(eOut.enc, eIn.enc)
+		}
+
+		out[extNum] = eOut
+	}
+}

go/vendor/github.com/golang/protobuf/proto/decode.go

+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2010 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
+
+/*
+ * Routines for decoding protocol buffer data to construct in-memory representations.
+ */
+
+import (
+	"errors"
+	"fmt"
+	"io"
+	"os"
+	"reflect"
+)
+
+// errOverflow is returned when an integer is too large to be represented.
+var errOverflow = errors.New("proto: integer overflow")
+
+// ErrInternalBadWireType is returned by generated code when an incorrect
+// wire type is encountered. It does not get returned to user code.
+var ErrInternalBadWireType = errors.New("proto: internal error: bad wiretype for oneof")
+
+// The fundamental decoders that interpret bytes on the wire.
+// Those that take integer types all return uint64 and are
+// therefore of type valueDecoder.
+
+// DecodeVarint reads a varint-encoded integer from the slice.
+// It returns the integer and the number of bytes consumed, or
+// zero if there is not enough.
+// This is the format for the
+// int32, int64, uint32, uint64, bool, and enum
+// protocol buffer types.
+func DecodeVarint(buf []byte) (x uint64, n int) {
+	for shift := uint(0); shift < 64; shift += 7 {
+		if n >= len(buf) {
+			return 0, 0
+		}
+		b := uint64(buf[n])
+		n++
+		x |= (b & 0x7F) << shift
+		if (b & 0x80) == 0 {
+			return x, n
+		}
+	}
+
+	// The number is too large to represent in a 64-bit value.
+	return 0, 0
+}
+
+func (p *Buffer) decodeVarintSlow() (x uint64, err error) {
+	i := p.index
+	l := len(p.buf)
+
+	for shift := uint(0); shift < 64; shift += 7 {
+		if i >= l {
+			err = io.ErrUnexpectedEOF
+			return
+		}
+		b := p.buf[i]
+		i++
+		x |= (uint64(b) & 0x7F) << shift
+		if b < 0x80 {
+			p.index = i
+			return
+		}
+	}
+
+	// The number is too large to represent in a 64-bit value.
+	err = errOverflow
+	return
+}
+
+// DecodeVarint reads a varint-encoded integer from the Buffer.
+// This is the format for the
+// int32, int64, uint32, uint64, bool, and enum
+// protocol buffer types.
+func (p *Buffer) DecodeVarint() (x uint64, err error) {
+	i := p.index
+	buf := p.buf
+
+	if i >= len(buf) {
+		return 0, io.ErrUnexpectedEOF
+	} else if buf[i] < 0x80 {
+		p.index++
+		return uint64(buf[i]), nil
+	} else if len(buf)-i < 10 {
+		return p.decodeVarintSlow()
+	}
+
+	var b uint64
+	// we already checked the first byte
+	x = uint64(buf[i]) - 0x80
+	i++
+
+	b = uint64(buf[i])
+	i++
+	x += b << 7
+	if b&0x80 == 0 {
+		goto done
+	}
+	x -= 0x80 << 7
+
+	b = uint64(buf[i])
+	i++
+	x += b << 14
+	if b&0x80 == 0 {
+		goto done
+	}
+	x -= 0x80 << 14
+
+	b = uint64(buf[i])
+	i++
+	x += b << 21
+	if b&0x80 == 0 {
+		goto done
+	}
+	x -= 0x80 << 21
+
+	b = uint64(buf[i])
+	i++
+	x += b << 28
+	if b&0x80 == 0 {
+		goto done
+	}
+	x -= 0x80 << 28
+
+	b = uint64(buf[i])
+	i++
+	x += b << 35
+	if b&0x80 == 0 {
+		goto done
+	}
+	x -= 0x80 << 35
+
+	b = uint64(buf[i])
+	i++
+	x += b << 42
+	if b&0x80 == 0 {
+		goto done
+	}
+	x -= 0x80 << 42
+
+	b = uint64(buf[i])
+	i++
+	x += b << 49
+	if b&0x80 == 0 {
+		goto done
+	}
+	x -= 0x80 << 49
+
+	b = uint64(buf[i])
+	i++
+	x += b << 56
+	if b&0x80 == 0 {
+		goto done
+	}
+	x -= 0x80 << 56
+
+	b = uint64(buf[i])
+	i++
+	x += b << 63
+	if b&0x80 == 0 {
+		goto done
+	}
+	// x -= 0x80 << 63 // Always zero.
+
+	return 0, errOverflow
+
+done:
+	p.index = i
+	return x, nil
+}
+
+// DecodeFixed64 reads a 64-bit integer from the Buffer.
+// This is the format for the
+// fixed64, sfixed64, and double protocol buffer types.
+func (p *Buffer) DecodeFixed64() (x uint64, err error) {
+	// x, err already 0
+	i := p.index + 8
+	if i < 0 || i > len(p.buf) {
+		err = io.ErrUnexpectedEOF
+		return
+	}
+	p.index = i
+
+	x = uint64(p.buf[i-8])
+	x |= uint64(p.buf[i-7]) << 8
+	x |= uint64(p.buf[i-6]) << 16
+	x |= uint64(p.buf[i-5]) << 24
+	x |= uint64(p.buf[i-4]) << 32
+	x |= uint64(p.buf[i-3]) << 40
+	x |= uint64(p.buf[i-2]) << 48
+	x |= uint64(p.buf[i-1]) << 56
+	return
+}
+
+// DecodeFixed32 reads a 32-bit integer from the Buffer.
+// This is the format for the
+// fixed32, sfixed32, and float protocol buffer types.
+func (p *Buffer) DecodeFixed32() (x uint64, err error) {
+	// x, err already 0
+	i := p.index + 4
+	if i < 0 || i > len(p.buf) {
+		err = io.ErrUnexpectedEOF
+		return
+	}
+	p.index = i
+
+	x = uint64(p.buf[i-4])
+	x |= uint64(p.buf[i-3]) << 8
+	x |= uint64(p.buf[i-2]) << 16
+	x |= uint64(p.buf[i-1]) << 24
+	return
+}
+
+// DecodeZigzag64 reads a zigzag-encoded 64-bit integer
+// from the Buffer.
+// This is the format used for the sint64 protocol buffer type.
+func (p *Buffer) DecodeZigzag64() (x uint64, err error) {
+	x, err = p.DecodeVarint()
+	if err != nil {
+		return
+	}
+	x = (x >> 1) ^ uint64((int64(x&1)<<63)>>63)
+	return
+}
+
+// DecodeZigzag32 reads a zigzag-encoded 32-bit integer
+// from  the Buffer.
+// This is the format used for the sint32 protocol buffer type.
+func (p *Buffer) DecodeZigzag32() (x uint64, err error) {
+	x, err = p.DecodeVarint()
+	if err != nil {
+		return
+	}
+	x = uint64((uint32(x) >> 1) ^ uint32((int32(x&1)<<31)>>31))
+	return
+}
+
+// These are not ValueDecoders: they produce an array of bytes or a string.
+// bytes, embedded messages
+
+// DecodeRawBytes reads a count-delimited byte buffer from the Buffer.
+// This is the format used for the bytes protocol buffer
+// type and for embedded messages.
+func (p *Buffer) DecodeRawBytes(alloc bool) (buf []byte, err error) {
+	n, err := p.DecodeVarint()
+	if err != nil {
+		return nil, err
+	}
+
+	nb := int(n)
+	if nb < 0 {
+		return nil, fmt.Errorf("proto: bad byte length %d", nb)
+	}
+	end := p.index + nb
+	if end < p.index || end > len(p.buf) {
+		return nil, io.ErrUnexpectedEOF
+	}
+
+	if !alloc {
+		// todo: check if can get more uses of alloc=false
+		buf = p.buf[p.index:end]
+		p.index += nb
+		return
+	}
+
+	buf = make([]byte, nb)
+	copy(buf, p.buf[p.index:])
+	p.index += nb
+	return
+}
+
+// DecodeStringBytes reads an encoded string from the Buffer.
+// This is the format used for the proto2 string type.
+func (p *Buffer) DecodeStringBytes() (s string, err error) {
+	buf, err := p.DecodeRawBytes(false)
+	if err != nil {
+		return
+	}
+	return string(buf), nil
+}
+
+// Skip the next item in the buffer. Its wire type is decoded and presented as an argument.
+// If the protocol buffer has extensions, and the field matches, add it as an extension.
+// Otherwise, if the XXX_unrecognized field exists, append the skipped data there.
+func (o *Buffer) skipAndSave(t reflect.Type, tag, wire int, base structPointer, unrecField field) error {
+	oi := o.index
+
+	err := o.skip(t, tag, wire)
+	if err != nil {
+		return err
+	}
+
+	if !unrecField.IsValid() {
+		return nil
+	}
+
+	ptr := structPointer_Bytes(base, unrecField)
+
+	// Add the skipped field to struct field
+	obuf := o.buf
+
+	o.buf = *ptr
+	o.EncodeVarint(uint64(tag<<3 | wire))
+	*ptr = append(o.buf, obuf[oi:o.index]...)
+
+	o.buf = obuf
+
+	return nil
+}
+
+// Skip the next item in the buffer. Its wire type is decoded and presented as an argument.
+func (o *Buffer) skip(t reflect.Type, tag, wire int) error {
+
+	var u uint64
+	var err error
+
+	switch wire {
+	case WireVarint:
+		_, err = o.DecodeVarint()
+	case WireFixed64:
+		_, err = o.DecodeFixed64()
+	case WireBytes:
+		_, err = o.DecodeRawBytes(false)
+	case WireFixed32:
+		_, err = o.DecodeFixed32()
+	case WireStartGroup:
+		for {
+			u, err = o.DecodeVarint()
+			if err != nil {
+				break
+			}
+			fwire := int(u & 0x7)
+			if fwire == WireEndGroup {
+				break
+			}
+			ftag := int(u >> 3)
+			err = o.skip(t, ftag, fwire)
+			if err != nil {
+				break
+			}
+		}
+	default:
+		err = fmt.Errorf("proto: can't skip unknown wire type %d for %s", wire, t)
+	}
+	return err
+}
+
+// Unmarshaler is the interface representing objects that can
+// unmarshal themselves.  The method should reset the receiver before
+// decoding starts.  The argument points to data that may be
+// overwritten, so implementations should not keep references to the
+// buffer.
+type Unmarshaler interface {
+	Unmarshal([]byte) error
+}
+
+// Unmarshal parses the protocol buffer representation in buf and places the
+// decoded result in pb.  If the struct underlying pb does not match
+// the data in buf, the results can be unpredictable.
+//
+// Unmarshal resets pb before starting to unmarshal, so any
+// existing data in pb is always removed. Use UnmarshalMerge
+// to preserve and append to existing data.
+func Unmarshal(buf []byte, pb Message) error {
+	pb.Reset()
+	return UnmarshalMerge(buf, pb)
+}
+
+// UnmarshalMerge parses the protocol buffer representation in buf and
+// writes the decoded result to pb.  If the struct underlying pb does not match
+// the data in buf, the results can be unpredictable.
+//
+// UnmarshalMerge merges into existing data in pb.
+// Most code should use Unmarshal instead.
+func UnmarshalMerge(buf []byte, pb Message) error {
+	// If the object can unmarshal itself, let it.
+	if u, ok := pb.(Unmarshaler); ok {
+		return u.Unmarshal(buf)
+	}
+	return NewBuffer(buf).Unmarshal(pb)
+}
+
+// DecodeMessage reads a count-delimited message from the Buffer.
+func (p *Buffer) DecodeMessage(pb Message) error {
+	enc, err := p.DecodeRawBytes(false)
+	if err != nil {
+		return err
+	}
+	return NewBuffer(enc).Unmarshal(pb)
+}
+
+// DecodeGroup reads a tag-delimited group from the Buffer.
+func (p *Buffer) DecodeGroup(pb Message) error {
+	typ, base, err := getbase(pb)
+	if err != nil {
+		return err
+	}
+	return p.unmarshalType(typ.Elem(), GetProperties(typ.Elem()), true, base)
+}
+
+// Unmarshal parses the protocol buffer representation in the
+// Buffer and places the decoded result in pb.  If the struct
+// underlying pb does not match the data in the buffer, the results can be
+// unpredictable.
+//
+// Unlike proto.Unmarshal, this does not reset pb before starting to unmarshal.
+func (p *Buffer) Unmarshal(pb Message) error {
+	// If the object can unmarshal itself, let it.
+	if u, ok := pb.(Unmarshaler); ok {
+		err := u.Unmarshal(p.buf[p.index:])
+		p.index = len(p.buf)
+		return err
+	}
+
+	typ, base, err := getbase(pb)
+	if err != nil {
+		return err
+	}
+
+	err = p.unmarshalType(typ.Elem(), GetProperties(typ.Elem()), false, base)
+
+	if collectStats {
+		stats.Decode++
+	}
+
+	return err
+}
+
+// unmarshalType does the work of unmarshaling a structure.
+func (o *Buffer) unmarshalType(st reflect.Type, prop *StructProperties, is_group bool, base structPointer) error {
+	var state errorState
+	required, reqFields := prop.reqCount, uint64(0)
+
+	var err error
+	for err == nil && o.index < len(o.buf) {
+		oi := o.index
+		var u uint64
+		u, err = o.DecodeVarint()
+		if err != nil {
+			break
+		}
+		wire := int(u & 0x7)
+		if wire == WireEndGroup {
+			if is_group {
+				if required > 0 {
+					// Not enough information to determine the exact field.
+					// (See below.)
+					return &RequiredNotSetError{"{Unknown}"}
+				}
+				return nil // input is satisfied
+			}
+			return fmt.Errorf("proto: %s: wiretype end group for non-group", st)
+		}
+		tag := int(u >> 3)
+		if tag <= 0 {
+			return fmt.Errorf("proto: %s: illegal tag %d (wire type %d)", st, tag, wire)
+		}
+		fieldnum, ok := prop.decoderTags.get(tag)
+		if !ok {
+			// Maybe it's an extension?
+			if prop.extendable {
+				if e, _ := extendable(structPointer_Interface(base, st)); isExtensionField(e, int32(tag)) {
+					if err = o.skip(st, tag, wire); err == nil {
+						extmap := e.extensionsWrite()
+						ext := extmap[int32(tag)] // may be missing
+						ext.enc = append(ext.enc, o.buf[oi:o.index]...)
+						extmap[int32(tag)] = ext
+					}
+					continue
+				}
+			}
+			// Maybe it's a oneof?
+			if prop.oneofUnmarshaler != nil {
+				m := structPointer_Interface(base, st).(Message)
+				// First return value indicates whether tag is a oneof field.
+				ok, err = prop.oneofUnmarshaler(m, tag, wire, o)
+				if err == ErrInternalBadWireType {
+					// Map the error to something more descriptive.
+					// Do the formatting here to save generated code space.
+					err = fmt.Errorf("bad wiretype for oneof field in %T", m)
+				}
+				if ok {
+					continue
+				}
+			}
+			err = o.skipAndSave(st, tag, wire, base, prop.unrecField)
+			continue
+		}
+		p := prop.Prop[fieldnum]
+
+		if p.dec == nil {
+			fmt.Fprintf(os.Stderr, "proto: no protobuf decoder for %s.%s\n", st, st.Field(fieldnum).Name)
+			continue
+		}
+		dec := p.dec
+		if wire != WireStartGroup && wire != p.WireType {
+			if wire == WireBytes && p.packedDec != nil {
+				// a packable field
+				dec = p.packedDec
+			} else {
+				err = fmt.Errorf("proto: bad wiretype for field %s.%s: got wiretype %d, want %d", st, st.Field(fieldnum).Name, wire, p.WireType)
+				continue
+			}
+		}
+		decErr := dec(o, p, base)
+		if decErr != nil && !state.shouldContinue(decErr, p) {
+			err = decErr
+		}
+		if err == nil && p.Required {
+			// Successfully decoded a required field.
+			if tag <= 64 {
+				// use bitmap for fields 1-64 to catch field reuse.
+				var mask uint64 = 1 << uint64(tag-1)
+				if reqFields&mask == 0 {
+					// new required field
+					reqFields |= mask
+					required--
+				}
+			} else {
+				// This is imprecise. It can be fooled by a required field
+				// with a tag > 64 that is encoded twice; that's very rare.
+				// A fully correct implementation would require allocating
+				// a data structure, which we would like to avoid.
+				required--
+			}
+		}
+	}
+	if err == nil {
+		if is_group {
+			return io.ErrUnexpectedEOF
+		}
+		if state.err != nil {
+			return state.err
+		}
+		if required > 0 {
+			// Not enough information to determine the exact field. If we use extra
+			// CPU, we could determine the field only if the missing required field
+			// has a tag <= 64 and we check reqFields.
+			return &RequiredNotSetError{"{Unknown}"}
+		}
+	}
+	return err
+}
+
+// Individual type decoders
+// For each,
+//	u is the decoded value,
+//	v is a pointer to the field (pointer) in the struct
+
+// Sizes of the pools to allocate inside the Buffer.
+// The goal is modest amortization and allocation
+// on at least 16-byte boundaries.
+const (
+	boolPoolSize   = 16
+	uint32PoolSize = 8
+	uint64PoolSize = 4
+)
+
+// Decode a bool.
+func (o *Buffer) dec_bool(p *Properties, base structPointer) error {
+	u, err := p.valDec(o)
+	if err != nil {
+		return err
+	}
+	if len(o.bools) == 0 {
+		o.bools = make([]bool, boolPoolSize)
+	}
+	o.bools[0] = u != 0
+	*structPointer_Bool(base, p.field) = &o.bools[0]
+	o.bools = o.bools[1:]
+	return nil
+}
+
+func (o *Buffer) dec_proto3_bool(p *Properties, base structPointer) error {
+	u, err := p.valDec(o)
+	if err != nil {
+		return err
+	}
+	*structPointer_BoolVal(base, p.field) = u != 0
+	return nil
+}
+
+// Decode an int32.
+func (o *Buffer) dec_int32(p *Properties, base structPointer) error {
+	u, err := p.valDec(o)
+	if err != nil {
+		return err
+	}
+	word32_Set(structPointer_Word32(base, p.field), o, uint32(u))
+	return nil
+}
+
+func (o *Buffer) dec_proto3_int32(p *Properties, base structPointer) error {
+	u, err := p.valDec(o)
+	if err != nil {
+		return err
+	}
+	word32Val_Set(structPointer_Word32Val(base, p.field), uint32(u))
+	return nil
+}
+
+// Decode an int64.
+func (o *Buffer) dec_int64(p *Properties, base structPointer) error {
+	u, err := p.valDec(o)
+	if err != nil {
+		return err
+	}
+	word64_Set(structPointer_Word64(base, p.field), o, u)
+	return nil
+}
+
+func (o *Buffer) dec_proto3_int64(p *Properties, base structPointer) error {
+	u, err := p.valDec(o)
+	if err != nil {
+		return err
+	}
+	word64Val_Set(structPointer_Word64Val(base, p.field), o, u)
+	return nil
+}
+
+// Decode a string.
+func (o *Buffer) dec_string(p *Properties, base structPointer) error {
+	s, err := o.DecodeStringBytes()
+	if err != nil {
+		return err
+	}
+	*structPointer_String(base, p.field) = &s
+	return nil
+}
+
+func (o *Buffer) dec_proto3_string(p *Properties, base structPointer) error {
+	s, err := o.DecodeStringBytes()
+	if err != nil {
+		return err
+	}
+	*structPointer_StringVal(base, p.field) = s
+	return nil
+}
+
+// Decode a slice of bytes ([]byte).
+func (o *Buffer) dec_slice_byte(p *Properties, base structPointer) error {
+	b, err := o.DecodeRawBytes(true)
+	if err != nil {
+		return err
+	}
+	*structPointer_Bytes(base, p.field) = b
+	return nil
+}
+
+// Decode a slice of bools ([]bool).
+func (o *Buffer) dec_slice_bool(p *Properties, base structPointer) error {
+	u, err := p.valDec(o)
+	if err != nil {
+		return err
+	}
+	v := structPointer_BoolSlice(base, p.field)
+	*v = append(*v, u != 0)
+	return nil
+}
+
+// Decode a slice of bools ([]bool) in packed format.
+func (o *Buffer) dec_slice_packed_bool(p *Properties, base structPointer) error {
+	v := structPointer_BoolSlice(base, p.field)
+
+	nn, err := o.DecodeVarint()
+	if err != nil {
+		return err
+	}
+	nb := int(nn) // number of bytes of encoded bools
+	fin := o.index + nb
+	if fin < o.index {
+		return errOverflow
+	}
+
+	y := *v
+	for o.index < fin {
+		u, err := p.valDec(o)
+		if err != nil {
+			return err
+		}
+		y = append(y, u != 0)
+	}
+
+	*v = y
+	return nil
+}
+
+// Decode a slice of int32s ([]int32).
+func (o *Buffer) dec_slice_int32(p *Properties, base structPointer) error {
+	u, err := p.valDec(o)
+	if err != nil {
+		return err
+	}
+	structPointer_Word32Slice(base, p.field).Append(uint32(u))
+	return nil
+}
+
+// Decode a slice of int32s ([]int32) in packed format.
+func (o *Buffer) dec_slice_packed_int32(p *Properties, base structPointer) error {
+	v := structPointer_Word32Slice(base, p.field)
+
+	nn, err := o.DecodeVarint()
+	if err != nil {
+		return err
+	}
+	nb := int(nn) // number of bytes of encoded int32s
+
+	fin := o.index + nb
+	if fin < o.index {
+		return errOverflow
+	}
+	for o.index < fin {
+		u, err := p.valDec(o)
+		if err != nil {
+			return err
+		}
+		v.Append(uint32(u))
+	}
+	return nil
+}
+
+// Decode a slice of int64s ([]int64).
+func (o *Buffer) dec_slice_int64(p *Properties, base structPointer) error {
+	u, err := p.valDec(o)
+	if err != nil {
+		return err
+	}
+
+	structPointer_Word64Slice(base, p.field).Append(u)
+	return nil
+}
+
+// Decode a slice of int64s ([]int64) in packed format.
+func (o *Buffer) dec_slice_packed_int64(p *Properties, base structPointer) error {
+	v := structPointer_Word64Slice(base, p.field)
+
+	nn, err := o.DecodeVarint()
+	if err != nil {
+		return err
+	}
+	nb := int(nn) // number of bytes of encoded int64s
+
+	fin := o.index + nb
+	if fin < o.index {
+		return errOverflow
+	}
+	for o.index < fin {
+		u, err := p.valDec(o)
+		if err != nil {
+			return err
+		}
+		v.Append(u)
+	}
+	return nil
+}
+
+// Decode a slice of strings ([]string).
+func (o *Buffer) dec_slice_string(p *Properties, base structPointer) error {
+	s, err := o.DecodeStringBytes()
+	if err != nil {
+		return err
+	}
+	v := structPointer_StringSlice(base, p.field)
+	*v = append(*v, s)
+	return nil
+}
+
+// Decode a slice of slice of bytes ([][]byte).
+func (o *Buffer) dec_slice_slice_byte(p *Properties, base structPointer) error {
+	b, err := o.DecodeRawBytes(true)
+	if err != nil {
+		return err
+	}
+	v := structPointer_BytesSlice(base, p.field)
+	*v = append(*v, b)
+	return nil
+}
+
+// Decode a map field.
+func (o *Buffer) dec_new_map(p *Properties, base structPointer) error {
+	raw, err := o.DecodeRawBytes(false)
+	if err != nil {
+		return err
+	}
+	oi := o.index       // index at the end of this map entry
+	o.index -= len(raw) // move buffer back to start of map entry
+
+	mptr := structPointer_NewAt(base, p.field, p.mtype) // *map[K]V
+	if mptr.Elem().IsNil() {
+		mptr.Elem().Set(reflect.MakeMap(mptr.Type().Elem()))
+	}
+	v := mptr.Elem() // map[K]V
+
+	// Prepare addressable doubly-indirect placeholders for the key and value types.
+	// See enc_new_map for why.
+	keyptr := reflect.New(reflect.PtrTo(p.mtype.Key())).Elem() // addressable *K
+	keybase := toStructPointer(keyptr.Addr())                  // **K
+
+	var valbase structPointer
+	var valptr reflect.Value
+	switch p.mtype.Elem().Kind() {
+	case reflect.Slice:
+		// []byte
+		var dummy []byte
+		valptr = reflect.ValueOf(&dummy)  // *[]byte
+		valbase = toStructPointer(valptr) // *[]byte
+	case reflect.Ptr:
+		// message; valptr is **Msg; need to allocate the intermediate pointer
+		valptr = reflect.New(reflect.PtrTo(p.mtype.Elem())).Elem() // addressable *V
+		valptr.Set(reflect.New(valptr.Type().Elem()))
+		valbase = toStructPointer(valptr)
+	default:
+		// everything else
+		valptr = reflect.New(reflect.PtrTo(p.mtype.Elem())).Elem() // addressable *V
+		valbase = toStructPointer(valptr.Addr())                   // **V
+	}
+
+	// Decode.
+	// This parses a restricted wire format, namely the encoding of a message
+	// with two fields. See enc_new_map for the format.
+	for o.index < oi {
+		// tagcode for key and value properties are always a single byte
+		// because they have tags 1 and 2.
+		tagcode := o.buf[o.index]
+		o.index++
+		switch tagcode {
+		case p.mkeyprop.tagcode[0]:
+			if err := p.mkeyprop.dec(o, p.mkeyprop, keybase); err != nil {
+				return err
+			}
+		case p.mvalprop.tagcode[0]:
+			if err := p.mvalprop.dec(o, p.mvalprop, valbase); err != nil {
+				return err
+			}
+		default:
+			// TODO: Should we silently skip this instead?
+			return fmt.Errorf("proto: bad map data tag %d", raw[0])
+		}
+	}
+	keyelem, valelem := keyptr.Elem(), valptr.Elem()
+	if !keyelem.IsValid() {
+		keyelem = reflect.Zero(p.mtype.Key())
+	}
+	if !valelem.IsValid() {
+		valelem = reflect.Zero(p.mtype.Elem())
+	}
+
+	v.SetMapIndex(keyelem, valelem)
+	return nil
+}
+
+// Decode a group.
+func (o *Buffer) dec_struct_group(p *Properties, base structPointer) error {
+	bas := structPointer_GetStructPointer(base, p.field)
+	if structPointer_IsNil(bas) {
+		// allocate new nested message
+		bas = toStructPointer(reflect.New(p.stype))
+		structPointer_SetStructPointer(base, p.field, bas)
+	}
+	return o.unmarshalType(p.stype, p.sprop, true, bas)
+}
+
+// Decode an embedded message.
+func (o *Buffer) dec_struct_message(p *Properties, base structPointer) (err error) {
+	raw, e := o.DecodeRawBytes(false)
+	if e != nil {
+		return e
+	}
+
+	bas := structPointer_GetStructPointer(base, p.field)
+	if structPointer_IsNil(bas) {
+		// allocate new nested message
+		bas = toStructPointer(reflect.New(p.stype))
+		structPointer_SetStructPointer(base, p.field, bas)
+	}
+
+	// If the object can unmarshal itself, let it.
+	if p.isUnmarshaler {
+		iv := structPointer_Interface(bas, p.stype)
+		return iv.(Unmarshaler).Unmarshal(raw)
+	}
+
+	obuf := o.buf
+	oi := o.index
+	o.buf = raw
+	o.index = 0
+
+	err = o.unmarshalType(p.stype, p.sprop, false, bas)
+	o.buf = obuf
+	o.index = oi
+
+	return err
+}
+
+// Decode a slice of embedded messages.
+func (o *Buffer) dec_slice_struct_message(p *Properties, base structPointer) error {
+	return o.dec_slice_struct(p, false, base)
+}
+
+// Decode a slice of embedded groups.
+func (o *Buffer) dec_slice_struct_group(p *Properties, base structPointer) error {
+	return o.dec_slice_struct(p, true, base)
+}
+
+// Decode a slice of structs ([]*struct).
+func (o *Buffer) dec_slice_struct(p *Properties, is_group bool, base structPointer) error {
+	v := reflect.New(p.stype)
+	bas := toStructPointer(v)
+	structPointer_StructPointerSlice(base, p.field).Append(bas)
+
+	if is_group {
+		err := o.unmarshalType(p.stype, p.sprop, is_group, bas)
+		return err
+	}
+
+	raw, err := o.DecodeRawBytes(false)
+	if err != nil {
+		return err
+	}
+
+	// If the object can unmarshal itself, let it.
+	if p.isUnmarshaler {
+		iv := v.Interface()
+		return iv.(Unmarshaler).Unmarshal(raw)
+	}
+
+	obuf := o.buf
+	oi := o.index
+	o.buf = raw
+	o.index = 0
+
+	err = o.unmarshalType(p.stype, p.sprop, is_group, bas)
+
+	o.buf = obuf
+	o.index = oi
+
+	return err
+}

go/vendor/github.com/golang/protobuf/proto/encode.go

+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2010 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
+
+/*
+ * Routines for encoding data into the wire format for protocol buffers.
+ */
+
+import (
+	"errors"
+	"fmt"
+	"reflect"
+	"sort"
+)
+
+// RequiredNotSetError is the error returned if Marshal is called with
+// a protocol buffer struct whose required fields have not
+// all been initialized. It is also the error returned if Unmarshal is
+// called with an encoded protocol buffer that does not include all the
+// required fields.
+//
+// When printed, RequiredNotSetError reports the first unset required field in a
+// message. If the field cannot be precisely determined, it is reported as
+// "{Unknown}".
+type RequiredNotSetError struct {
+	field string
+}
+
+func (e *RequiredNotSetError) Error() string {
+	return fmt.Sprintf("proto: required field %q not set", e.field)
+}
+
+var (
+	// errRepeatedHasNil is the error returned if Marshal is called with
+	// a struct with a repeated field containing a nil element.
+	errRepeatedHasNil = errors.New("proto: repeated field has nil element")
+
+	// errOneofHasNil is the error returned if Marshal is called with
+	// a struct with a oneof field containing a nil element.
+	errOneofHasNil = errors.New("proto: oneof field has nil value")
+
+	// ErrNil is the error returned if Marshal is called with nil.
+	ErrNil = errors.New("proto: Marshal called with nil")
+
+	// ErrTooLarge is the error returned if Marshal is called with a
+	// message that encodes to >2GB.
+	ErrTooLarge = errors.New("proto: message encodes to over 2 GB")
+)
+
+// The fundamental encoders that put bytes on the wire.
+// Those that take integer types all accept uint64 and are
+// therefore of type valueEncoder.
+
+const maxVarintBytes = 10 // maximum length of a varint
+
+// maxMarshalSize is the largest allowed size of an encoded protobuf,
+// since C++ and Java use signed int32s for the size.
+const maxMarshalSize = 1<<31 - 1
+
+// EncodeVarint returns the varint encoding of x.
+// This is the format for the
+// int32, int64, uint32, uint64, bool, and enum
+// protocol buffer types.
+// Not used by the package itself, but helpful to clients
+// wishing to use the same encoding.
+func EncodeVarint(x uint64) []byte {
+	var buf [maxVarintBytes]byte
+	var n int
+	for n = 0; x > 127; n++ {
+		buf[n] = 0x80 | uint8(x&0x7F)
+		x >>= 7
+	}
+	buf[n] = uint8(x)
+	n++
+	return buf[0:n]
+}
+
+// EncodeVarint writes a varint-encoded integer to the Buffer.
+// This is the format for the
+// int32, int64, uint32, uint64, bool, and enum
+// protocol buffer types.
+func (p *Buffer) EncodeVarint(x uint64) error {
+	for x >= 1<<7 {
+		p.buf = append(p.buf, uint8(x&0x7f|0x80))
+		x >>= 7
+	}
+	p.buf = append(p.buf, uint8(x))
+	return nil
+}
+
+// SizeVarint returns the varint encoding size of an integer.
+func SizeVarint(x uint64) int {
+	return sizeVarint(x)
+}
+
+func sizeVarint(x uint64) (n int) {
+	for {
+		n++
+		x >>= 7
+		if x == 0 {
+			break
+		}
+	}
+	return n
+}
+
+// EncodeFixed64 writes a 64-bit integer to the Buffer.
+// This is the format for the
+// fixed64, sfixed64, and double protocol buffer types.
+func (p *Buffer) EncodeFixed64(x uint64) error {
+	p.buf = append(p.buf,
+		uint8(x),
+		uint8(x>>8),
+		uint8(x>>16),
+		uint8(x>>24),
+		uint8(x>>32),
+		uint8(x>>40),
+		uint8(x>>48),
+		uint8(x>>56))
+	return nil
+}
+
+func sizeFixed64(x uint64) int {
+	return 8
+}
+
+// EncodeFixed32 writes a 32-bit integer to the Buffer.
+// This is the format for the
+// fixed32, sfixed32, and float protocol buffer types.
+func (p *Buffer) EncodeFixed32(x uint64) error {
+	p.buf = append(p.buf,
+		uint8(x),
+		uint8(x>>8),
+		uint8(x>>16),
+		uint8(x>>24))
+	return nil
+}
+
+func sizeFixed32(x uint64) int {
+	return 4
+}
+
+// EncodeZigzag64 writes a zigzag-encoded 64-bit integer
+// to the Buffer.
+// This is the format used for the sint64 protocol buffer type.
+func (p *Buffer) EncodeZigzag64(x uint64) error {
+	// use signed number to get arithmetic right shift.
+	return p.EncodeVarint(uint64((x << 1) ^ uint64((int64(x) >> 63))))
+}
+
+func sizeZigzag64(x uint64) int {
+	return sizeVarint(uint64((x << 1) ^ uint64((int64(x) >> 63))))
+}
+
+// EncodeZigzag32 writes a zigzag-encoded 32-bit integer
+// to the Buffer.
+// This is the format used for the sint32 protocol buffer type.
+func (p *Buffer) EncodeZigzag32(x uint64) error {
+	// use signed number to get arithmetic right shift.
+	return p.EncodeVarint(uint64((uint32(x) << 1) ^ uint32((int32(x) >> 31))))
+}
+
+func sizeZigzag32(x uint64) int {
+	return sizeVarint(uint64((uint32(x) << 1) ^ uint32((int32(x) >> 31))))
+}
+
+// EncodeRawBytes writes a count-delimited byte buffer to the Buffer.
+// This is the format used for the bytes protocol buffer
+// type and for embedded messages.
+func (p *Buffer) EncodeRawBytes(b []byte) error {
+	p.EncodeVarint(uint64(len(b)))
+	p.buf = append(p.buf, b...)
+	return nil
+}
+
+func sizeRawBytes(b []byte) int {
+	return sizeVarint(uint64(len(b))) +
+		len(b)
+}
+
+// EncodeStringBytes writes an encoded string to the Buffer.
+// This is the format used for the proto2 string type.
+func (p *Buffer) EncodeStringBytes(s string) error {
+	p.EncodeVarint(uint64(len(s)))
+	p.buf = append(p.buf, s...)
+	return nil
+}
+
+func sizeStringBytes(s string) int {
+	return sizeVarint(uint64(len(s))) +
+		len(s)
+}
+
+// Marshaler is the interface representing objects that can marshal themselves.
+type Marshaler interface {
+	Marshal() ([]byte, error)
+}
+
+// Marshal takes the protocol buffer
+// and encodes it into the wire format, returning the data.
+func Marshal(pb Message) ([]byte, error) {
+	// Can the object marshal itself?
+	if m, ok := pb.(Marshaler); ok {
+		return m.Marshal()
+	}
+	p := NewBuffer(nil)
+	err := p.Marshal(pb)
+	if p.buf == nil && err == nil {
+		// Return a non-nil slice on success.
+		return []byte{}, nil
+	}
+	return p.buf, err
+}
+
+// EncodeMessage writes the protocol buffer to the Buffer,
+// prefixed by a varint-encoded length.
+func (p *Buffer) EncodeMessage(pb Message) error {
+	t, base, err := getbase(pb)
+	if structPointer_IsNil(base) {
+		return ErrNil
+	}
+	if err == nil {
+		var state errorState
+		err = p.enc_len_struct(GetProperties(t.Elem()), base, &state)
+	}
+	return err
+}
+
+// Marshal takes the protocol buffer
+// and encodes it into the wire format, writing the result to the
+// Buffer.
+func (p *Buffer) Marshal(pb Message) error {
+	// Can the object marshal itself?
+	if m, ok := pb.(Marshaler); ok {
+		data, err := m.Marshal()
+		p.buf = append(p.buf, data...)
+		return err
+	}
+
+	t, base, err := getbase(pb)
+	if structPointer_IsNil(base) {
+		return ErrNil
+	}
+	if err == nil {
+		err = p.enc_struct(GetProperties(t.Elem()), base)
+	}
+
+	if collectStats {
+		(stats).Encode++ // Parens are to work around a goimports bug.
+	}
+
+	if len(p.buf) > maxMarshalSize {
+		return ErrTooLarge
+	}
+	return err
+}
+
+// Size returns the encoded size of a protocol buffer.
+func Size(pb Message) (n int) {
+	// Can the object marshal itself?  If so, Size is slow.
+	// TODO: add Size to Marshaler, or add a Sizer interface.
+	if m, ok := pb.(Marshaler); ok {
+		b, _ := m.Marshal()
+		return len(b)
+	}
+
+	t, base, err := getbase(pb)
+	if structPointer_IsNil(base) {
+		return 0
+	}
+	if err == nil {
+		n = size_struct(GetProperties(t.Elem()), base)
+	}
+
+	if collectStats {
+		(stats).Size++ // Parens are to work around a goimports bug.
+	}
+
+	return
+}
+
+// Individual type encoders.
+
+// Encode a bool.
+func (o *Buffer) enc_bool(p *Properties, base structPointer) error {
+	v := *structPointer_Bool(base, p.field)
+	if v == nil {
+		return ErrNil
+	}
+	x := 0
+	if *v {
+		x = 1
+	}
+	o.buf = append(o.buf, p.tagcode...)
+	p.valEnc(o, uint64(x))
+	return nil
+}
+
+func (o *Buffer) enc_proto3_bool(p *Properties, base structPointer) error {
+	v := *structPointer_BoolVal(base, p.field)
+	if !v {
+		return ErrNil
+	}
+	o.buf = append(o.buf, p.tagcode...)
+	p.valEnc(o, 1)
+	return nil
+}
+
+func size_bool(p *Properties, base structPointer) int {
+	v := *structPointer_Bool(base, p.field)
+	if v == nil {
+		return 0
+	}
+	return len(p.tagcode) + 1 // each bool takes exactly one byte
+}
+
+func size_proto3_bool(p *Properties, base structPointer) int {
+	v := *structPointer_BoolVal(base, p.field)
+	if !v && !p.oneof {
+		return 0
+	}
+	return len(p.tagcode) + 1 // each bool takes exactly one byte
+}
+
+// Encode an int32.
+func (o *Buffer) enc_int32(p *Properties, base structPointer) error {
+	v := structPointer_Word32(base, p.field)
+	if word32_IsNil(v) {
+		return ErrNil
+	}
+	x := int32(word32_Get(v)) // permit sign extension to use full 64-bit range
+	o.buf = append(o.buf, p.tagcode...)
+	p.valEnc(o, uint64(x))
+	return nil
+}
+
+func (o *Buffer) enc_proto3_int32(p *Properties, base structPointer) error {
+	v := structPointer_Word32Val(base, p.field)
+	x := int32(word32Val_Get(v)) // permit sign extension to use full 64-bit range
+	if x == 0 {
+		return ErrNil
+	}
+	o.buf = append(o.buf, p.tagcode...)
+	p.valEnc(o, uint64(x))
+	return nil
+}
+
+func size_int32(p *Properties, base structPointer) (n int) {
+	v := structPointer_Word32(base, p.field)
+	if word32_IsNil(v) {
+		return 0
+	}
+	x := int32(word32_Get(v)) // permit sign extension to use full 64-bit range
+	n += len(p.tagcode)
+	n += p.valSize(uint64(x))
+	return
+}
+
+func size_proto3_int32(p *Properties, base structPointer) (n int) {
+	v := structPointer_Word32Val(base, p.field)
+	x := int32(word32Val_Get(v)) // permit sign extension to use full 64-bit range
+	if x == 0 && !p.oneof {
+		return 0
+	}
+	n += len(p.tagcode)
+	n += p.valSize(uint64(x))
+	return
+}
+
+// Encode a uint32.
+// Exactly the same as int32, except for no sign extension.
+func (o *Buffer) enc_uint32(p *Properties, base structPointer) error {
+	v := structPointer_Word32(base, p.field)
+	if word32_IsNil(v) {
+		return ErrNil
+	}
+	x := word32_Get(v)
+	o.buf = append(o.buf, p.tagcode...)
+	p.valEnc(o, uint64(x))
+	return nil
+}
+
+func (o *Buffer) enc_proto3_uint32(p *Properties, base structPointer) error {
+	v := structPointer_Word32Val(base, p.field)
+	x := word32Val_Get(v)
+	if x == 0 {
+		return ErrNil
+	}
+	o.buf = append(o.buf, p.tagcode...)
+	p.valEnc(o, uint64(x))
+	return nil
+}
+
+func size_uint32(p *Properties, base structPointer) (n int) {
+	v := structPointer_Word32(base, p.field)
+	if word32_IsNil(v) {
+		return 0
+	}
+	x := word32_Get(v)
+	n += len(p.tagcode)
+	n += p.valSize(uint64(x))
+	return
+}
+
+func size_proto3_uint32(p *Properties, base structPointer) (n int) {
+	v := structPointer_Word32Val(base, p.field)
+	x := word32Val_Get(v)
+	if x == 0 && !p.oneof {
+		return 0
+	}
+	n += len(p.tagcode)
+	n += p.valSize(uint64(x))
+	return
+}
+
+// Encode an int64.
+func (o *Buffer) enc_int64(p *Properties, base structPointer) error {
+	v := structPointer_Word64(base, p.field)
+	if word64_IsNil(v) {
+		return ErrNil
+	}
+	x := word64_Get(v)
+	o.buf = append(o.buf, p.tagcode...)
+	p.valEnc(o, x)
+	return nil
+}
+
+func (o *Buffer) enc_proto3_int64(p *Properties, base structPointer) error {
+	v := structPointer_Word64Val(base, p.field)
+	x := word64Val_Get(v)
+	if x == 0 {
+		return ErrNil
+	}
+	o.buf = append(o.buf, p.tagcode...)
+	p.valEnc(o, x)
+	return nil
+}
+
+func size_int64(p *Properties, base structPointer) (n int) {
+	v := structPointer_Word64(base, p.field)
+	if word64_IsNil(v) {
+		return 0
+	}
+	x := word64_Get(v)
+	n += len(p.tagcode)
+	n += p.valSize(x)
+	return
+}
+
+func size_proto3_int64(p *Properties, base structPointer) (n int) {
+	v := structPointer_Word64Val(base, p.field)
+	x := word64Val_Get(v)
+	if x == 0 && !p.oneof {
+		return 0
+	}
+	n += len(p.tagcode)
+	n += p.valSize(x)
+	return
+}
+
+// Encode a string.
+func (o *Buffer) enc_string(p *Properties, base structPointer) error {
+	v := *structPointer_String(base, p.field)
+	if v == nil {
+		return ErrNil
+	}
+	x := *v
+	o.buf = append(o.buf, p.tagcode...)
+	o.EncodeStringBytes(x)
+	return nil
+}
+
+func (o *Buffer) enc_proto3_string(p *Properties, base structPointer) error {
+	v := *structPointer_StringVal(base, p.field)
+	if v == "" {
+		return ErrNil
+	}
+	o.buf = append(o.buf, p.tagcode...)
+	o.EncodeStringBytes(v)
+	return nil
+}
+
+func size_string(p *Properties, base structPointer) (n int) {
+	v := *structPointer_String(base, p.field)
+	if v == nil {
+		return 0
+	}
+	x := *v
+	n += len(p.tagcode)
+	n += sizeStringBytes(x)
+	return
+}
+
+func size_proto3_string(p *Properties, base structPointer) (n int) {
+	v := *structPointer_StringVal(base, p.field)
+	if v == "" && !p.oneof {
+		return 0
+	}
+	n += len(p.tagcode)
+	n += sizeStringBytes(v)
+	return
+}
+
+// All protocol buffer fields are nillable, but be careful.
+func isNil(v reflect.Value) bool {
+	switch v.Kind() {
+	case reflect.Interface, reflect.Map, reflect.Ptr, reflect.Slice:
+		return v.IsNil()
+	}
+	return false
+}
+
+// Encode a message struct.
+func (o *Buffer) enc_struct_message(p *Properties, base structPointer) error {
+	var state errorState
+	structp := structPointer_GetStructPointer(base, p.field)
+	if structPointer_IsNil(structp) {
+		return ErrNil
+	}
+
+	// Can the object marshal itself?
+	if p.isMarshaler {
+		m := structPointer_Interface(structp, p.stype).(Marshaler)
+		data, err := m.Marshal()
+		if err != nil && !state.shouldContinue(err, nil) {
+			return err
+		}
+		o.buf = append(o.buf, p.tagcode...)
+		o.EncodeRawBytes(data)
+		return state.err
+	}
+
+	o.buf = append(o.buf, p.tagcode...)
+	return o.enc_len_struct(p.sprop, structp, &state)
+}
+
+func size_struct_message(p *Properties, base structPointer) int {
+	structp := structPointer_GetStructPointer(base, p.field)
+	if structPointer_IsNil(structp) {
+		return 0
+	}
+
+	// Can the object marshal itself?
+	if p.isMarshaler {
+		m := structPointer_Interface(structp, p.stype).(Marshaler)
+		data, _ := m.Marshal()
+		n0 := len(p.tagcode)
+		n1 := sizeRawBytes(data)
+		return n0 + n1
+	}
+
+	n0 := len(p.tagcode)
+	n1 := size_struct(p.sprop, structp)
+	n2 := sizeVarint(uint64(n1)) // size of encoded length
+	return n0 + n1 + n2
+}
+
+// Encode a group struct.
+func (o *Buffer) enc_struct_group(p *Properties, base structPointer) error {
+	var state errorState
+	b := structPointer_GetStructPointer(base, p.field)
+	if structPointer_IsNil(b) {
+		return ErrNil
+	}
+
+	o.EncodeVarint(uint64((p.Tag << 3) | WireStartGroup))
+	err := o.enc_struct(p.sprop, b)
+	if err != nil && !state.shouldContinue(err, nil) {
+		return err
+	}
+	o.EncodeVarint(uint64((p.Tag << 3) | WireEndGroup))
+	return state.err
+}
+
+func size_struct_group(p *Properties, base structPointer) (n int) {
+	b := structPointer_GetStructPointer(base, p.field)
+	if structPointer_IsNil(b) {
+		return 0
+	}
+
+	n += sizeVarint(uint64((p.Tag << 3) | WireStartGroup))
+	n += size_struct(p.sprop, b)
+	n += sizeVarint(uint64((p.Tag << 3) | WireEndGroup))
+	return
+}
+
+// Encode a slice of bools ([]bool).
+func (o *Buffer) enc_slice_bool(p *Properties, base structPointer) error {
+	s := *structPointer_BoolSlice(base, p.field)
+	l := len(s)
+	if l == 0 {
+		return ErrNil
+	}
+	for _, x := range s {
+		o.buf = append(o.buf, p.tagcode...)
+		v := uint64(0)
+		if x {
+			v = 1
+		}
+		p.valEnc(o, v)
+	}
+	return nil
+}
+
+func size_slice_bool(p *Properties, base structPointer) int {
+	s := *structPointer_BoolSlice(base, p.field)
+	l := len(s)
+	if l == 0 {
+		return 0
+	}
+	return l * (len(p.tagcode) + 1) // each bool takes exactly one byte
+}
+
+// Encode a slice of bools ([]bool) in packed format.
+func (o *Buffer) enc_slice_packed_bool(p *Properties, base structPointer) error {
+	s := *structPointer_BoolSlice(base, p.field)
+	l := len(s)
+	if l == 0 {
+		return ErrNil
+	}
+	o.buf = append(o.buf, p.tagcode...)
+	o.EncodeVarint(uint64(l)) // each bool takes exactly one byte
+	for _, x := range s {
+		v := uint64(0)
+		if x {
+			v = 1
+		}
+		p.valEnc(o, v)
+	}
+	return nil
+}
+
+func size_slice_packed_bool(p *Properties, base structPointer) (n int) {
+	s := *structPointer_BoolSlice(base, p.field)
+	l := len(s)
+	if l == 0 {
+		return 0
+	}
+	n += len(p.tagcode)
+	n += sizeVarint(uint64(l))
+	n += l // each bool takes exactly one byte
+	return
+}
+
+// Encode a slice of bytes ([]byte).
+func (o *Buffer) enc_slice_byte(p *Properties, base structPointer) error {
+	s := *structPointer_Bytes(base, p.field)
+	if s == nil {
+		return ErrNil
+	}
+	o.buf = append(o.buf, p.tagcode...)
+	o.EncodeRawBytes(s)
+	return nil
+}
+
+func (o *Buffer) enc_proto3_slice_byte(p *Properties, base structPointer) error {
+	s := *structPointer_Bytes(base, p.field)
+	if len(s) == 0 {
+		return ErrNil
+	}
+	o.buf = append(o.buf, p.tagcode...)
+	o.EncodeRawBytes(s)
+	return nil
+}
+
+func size_slice_byte(p *Properties, base structPointer) (n int) {
+	s := *structPointer_Bytes(base, p.field)
+	if s == nil && !p.oneof {
+		return 0
+	}
+	n += len(p.tagcode)
+	n += sizeRawBytes(s)
+	return
+}
+
+func size_proto3_slice_byte(p *Properties, base structPointer) (n int) {
+	s := *structPointer_Bytes(base, p.field)
+	if len(s) == 0 && !p.oneof {
+		return 0
+	}
+	n += len(p.tagcode)
+	n += sizeRawBytes(s)
+	return
+}
+
+// Encode a slice of int32s ([]int32).
+func (o *Buffer) enc_slice_int32(p *Properties, base structPointer) error {
+	s := structPointer_Word32Slice(base, p.field)
+	l := s.Len()
+	if l == 0 {
+		return ErrNil
+	}
+	for i := 0; i < l; i++ {
+		o.buf = append(o.buf, p.tagcode...)
+		x := int32(s.Index(i)) // permit sign extension to use full 64-bit range
+		p.valEnc(o, uint64(x))
+	}
+	return nil
+}
+
+func size_slice_int32(p *Properties, base structPointer) (n int) {
+	s := structPointer_Word32Slice(base, p.field)
+	l := s.Len()
+	if l == 0 {
+		return 0
+	}
+	for i := 0; i < l; i++ {
+		n += len(p.tagcode)
+		x := int32(s.Index(i)) // permit sign extension to use full 64-bit range
+		n += p.valSize(uint64(x))
+	}
+	return
+}
+
+// Encode a slice of int32s ([]int32) in packed format.
+func (o *Buffer) enc_slice_packed_int32(p *Properties, base structPointer) error {
+	s := structPointer_Word32Slice(base, p.field)
+	l := s.Len()
+	if l == 0 {
+		return ErrNil
+	}
+	// TODO: Reuse a Buffer.
+	buf := NewBuffer(nil)
+	for i := 0; i < l; i++ {
+		x := int32(s.Index(i)) // permit sign extension to use full 64-bit range
+		p.valEnc(buf, uint64(x))
+	}
+
+	o.buf = append(o.buf, p.tagcode...)
+	o.EncodeVarint(uint64(len(buf.buf)))
+	o.buf = append(o.buf, buf.buf...)
+	return nil
+}
+
+func size_slice_packed_int32(p *Properties, base structPointer) (n int) {
+	s := structPointer_Word32Slice(base, p.field)
+	l := s.Len()
+	if l == 0 {
+		return 0
+	}
+	var bufSize int
+	for i := 0; i < l; i++ {
+		x := int32(s.Index(i)) // permit sign extension to use full 64-bit range
+		bufSize += p.valSize(uint64(x))
+	}
+
+	n += len(p.tagcode)
+	n += sizeVarint(uint64(bufSize))
+	n += bufSize
+	return
+}
+
+// Encode a slice of uint32s ([]uint32).
+// Exactly the same as int32, except for no sign extension.
+func (o *Buffer) enc_slice_uint32(p *Properties, base structPointer) error {
+	s := structPointer_Word32Slice(base, p.field)
+	l := s.Len()
+	if l == 0 {
+		return ErrNil
+	}
+	for i := 0; i < l; i++ {
+		o.buf = append(o.buf, p.tagcode...)
+		x := s.Index(i)
+		p.valEnc(o, uint64(x))
+	}
+	return nil
+}
+
+func size_slice_uint32(p *Properties, base structPointer) (n int) {
+	s := structPointer_Word32Slice(base, p.field)
+	l := s.Len()
+	if l == 0 {
+		return 0
+	}
+	for i := 0; i < l; i++ {
+		n += len(p.tagcode)
+		x := s.Index(i)
+		n += p.valSize(uint64(x))
+	}
+	return
+}
+
+// Encode a slice of uint32s ([]uint32) in packed format.
+// Exactly the same as int32, except for no sign extension.
+func (o *Buffer) enc_slice_packed_uint32(p *Properties, base structPointer) error {
+	s := structPointer_Word32Slice(base, p.field)
+	l := s.Len()
+	if l == 0 {
+		return ErrNil
+	}
+	// TODO: Reuse a Buffer.
+	buf := NewBuffer(nil)
+	for i := 0; i < l; i++ {
+		p.valEnc(buf, uint64(s.Index(i)))
+	}
+
+	o.buf = append(o.buf, p.tagcode...)
+	o.EncodeVarint(uint64(len(buf.buf)))
+	o.buf = append(o.buf, buf.buf...)
+	return nil
+}
+
+func size_slice_packed_uint32(p *Properties, base structPointer) (n int) {
+	s := structPointer_Word32Slice(base, p.field)
+	l := s.Len()
+	if l == 0 {
+		return 0
+	}
+	var bufSize int
+	for i := 0; i < l; i++ {
+		bufSize += p.valSize(uint64(s.Index(i)))
+	}
+
+	n += len(p.tagcode)
+	n += sizeVarint(uint64(bufSize))
+	n += bufSize
+	return
+}
+
+// Encode a slice of int64s ([]int64).
+func (o *Buffer) enc_slice_int64(p *Properties, base structPointer) error {
+	s := structPointer_Word64Slice(base, p.field)
+	l := s.Len()
+	if l == 0 {
+		return ErrNil
+	}
+	for i := 0; i < l; i++ {
+		o.buf = append(o.buf, p.tagcode...)
+		p.valEnc(o, s.Index(i))
+	}
+	return nil
+}
+
+func size_slice_int64(p *Properties, base structPointer) (n int) {
+	s := structPointer_Word64Slice(base, p.field)
+	l := s.Len()
+	if l == 0 {
+		return 0
+	}
+	for i := 0; i < l; i++ {
+		n += len(p.tagcode)
+		n += p.valSize(s.Index(i))
+	}
+	return
+}
+
+// Encode a slice of int64s ([]int64) in packed format.
+func (o *Buffer) enc_slice_packed_int64(p *Properties, base structPointer) error {
+	s := structPointer_Word64Slice(base, p.field)
+	l := s.Len()
+	if l == 0 {
+		return ErrNil
+	}
+	// TODO: Reuse a Buffer.
+	buf := NewBuffer(nil)
+	for i := 0; i < l; i++ {
+		p.valEnc(buf, s.Index(i))
+	}
+
+	o.buf = append(o.buf, p.tagcode...)
+	o.EncodeVarint(uint64(len(buf.buf)))
+	o.buf = append(o.buf, buf.buf...)
+	return nil
+}
+
+func size_slice_packed_int64(p *Properties, base structPointer) (n int) {
+	s := structPointer_Word64Slice(base, p.field)
+	l := s.Len()
+	if l == 0 {
+		return 0
+	}
+	var bufSize int
+	for i := 0; i < l; i++ {
+		bufSize += p.valSize(s.Index(i))
+	}
+
+	n += len(p.tagcode)
+	n += sizeVarint(uint64(bufSize))
+	n += bufSize
+	return
+}
+
+// Encode a slice of slice of bytes ([][]byte).
+func (o *Buffer) enc_slice_slice_byte(p *Properties, base structPointer) error {
+	ss := *structPointer_BytesSlice(base, p.field)
+	l := len(ss)
+	if l == 0 {
+		return ErrNil
+	}
+	for i := 0; i < l; i++ {
+		o.buf = append(o.buf, p.tagcode...)
+		o.EncodeRawBytes(ss[i])
+	}
+	return nil
+}
+
+func size_slice_slice_byte(p *Properties, base structPointer) (n int) {
+	ss := *structPointer_BytesSlice(base, p.field)
+	l := len(ss)
+	if l == 0 {
+		return 0
+	}
+	n += l * len(p.tagcode)
+	for i := 0; i < l; i++ {
+		n += sizeRawBytes(ss[i])
+	}
+	return
+}
+
+// Encode a slice of strings ([]string).
+func (o *Buffer) enc_slice_string(p *Properties, base structPointer) error {
+	ss := *structPointer_StringSlice(base, p.field)
+	l := len(ss)
+	for i := 0; i < l; i++ {
+		o.buf = append(o.buf, p.tagcode...)
+		o.EncodeStringBytes(ss[i])
+	}
+	return nil
+}
+
+func size_slice_string(p *Properties, base structPointer) (n int) {
+	ss := *structPointer_StringSlice(base, p.field)
+	l := len(ss)
+	n += l * len(p.tagcode)
+	for i := 0; i < l; i++ {
+		n += sizeStringBytes(ss[i])
+	}
+	return
+}
+
+// Encode a slice of message structs ([]*struct).
+func (o *Buffer) enc_slice_struct_message(p *Properties, base structPointer) error {
+	var state errorState
+	s := structPointer_StructPointerSlice(base, p.field)
+	l := s.Len()
+
+	for i := 0; i < l; i++ {
+		structp := s.Index(i)
+		if structPointer_IsNil(structp) {
+			return errRepeatedHasNil
+		}
+
+		// Can the object marshal itself?
+		if p.isMarshaler {
+			m := structPointer_Interface(structp, p.stype).(Marshaler)
+			data, err := m.Marshal()
+			if err != nil && !state.shouldContinue(err, nil) {
+				return err
+			}
+			o.buf = append(o.buf, p.tagcode...)
+			o.EncodeRawBytes(data)
+			continue
+		}
+
+		o.buf = append(o.buf, p.tagcode...)
+		err := o.enc_len_struct(p.sprop, structp, &state)
+		if err != nil && !state.shouldContinue(err, nil) {
+			if err == ErrNil {
+				return errRepeatedHasNil
+			}
+			return err
+		}
+	}
+	return state.err
+}
+
+func size_slice_struct_message(p *Properties, base structPointer) (n int) {
+	s := structPointer_StructPointerSlice(base, p.field)
+	l := s.Len()
+	n += l * len(p.tagcode)
+	for i := 0; i < l; i++ {
+		structp := s.Index(i)
+		if structPointer_IsNil(structp) {
+			return // return the size up to this point
+		}
+
+		// Can the object marshal itself?
+		if p.isMarshaler {
+			m := structPointer_Interface(structp, p.stype).(Marshaler)
+			data, _ := m.Marshal()
+			n += sizeRawBytes(data)
+			continue
+		}
+
+		n0 := size_struct(p.sprop, structp)
+		n1 := sizeVarint(uint64(n0)) // size of encoded length
+		n += n0 + n1
+	}
+	return
+}
+
+// Encode a slice of group structs ([]*struct).
+func (o *Buffer) enc_slice_struct_group(p *Properties, base structPointer) error {
+	var state errorState
+	s := structPointer_StructPointerSlice(base, p.field)
+	l := s.Len()
+
+	for i := 0; i < l; i++ {
+		b := s.Index(i)
+		if structPointer_IsNil(b) {
+			return errRepeatedHasNil
+		}
+
+		o.EncodeVarint(uint64((p.Tag << 3) | WireStartGroup))
+
+		err := o.enc_struct(p.sprop, b)
+
+		if err != nil && !state.shouldContinue(err, nil) {
+			if err == ErrNil {
+				return errRepeatedHasNil
+			}
+			return err
+		}
+
+		o.EncodeVarint(uint64((p.Tag << 3) | WireEndGroup))
+	}
+	return state.err
+}
+
+func size_slice_struct_group(p *Properties, base structPointer) (n int) {
+	s := structPointer_StructPointerSlice(base, p.field)
+	l := s.Len()
+
+	n += l * sizeVarint(uint64((p.Tag<<3)|WireStartGroup))
+	n += l * sizeVarint(uint64((p.Tag<<3)|WireEndGroup))
+	for i := 0; i < l; i++ {
+		b := s.Index(i)
+		if structPointer_IsNil(b) {
+			return // return size up to this point
+		}
+
+		n += size_struct(p.sprop, b)
+	}
+	return
+}
+
+// Encode an extension map.
+func (o *Buffer) enc_map(p *Properties, base structPointer) error {
+	exts := structPointer_ExtMap(base, p.field)
+	if err := encodeExtensionsMap(*exts); err != nil {
+		return err
+	}
+
+	return o.enc_map_body(*exts)
+}
+
+func (o *Buffer) enc_exts(p *Properties, base structPointer) error {
+	exts := structPointer_Extensions(base, p.field)
+
+	v, mu := exts.extensionsRead()
+	if v == nil {
+		return nil
+	}
+
+	mu.Lock()
+	defer mu.Unlock()
+	if err := encodeExtensionsMap(v); err != nil {
+		return err
+	}
+
+	return o.enc_map_body(v)
+}
+
+func (o *Buffer) enc_map_body(v map[int32]Extension) error {
+	// Fast-path for common cases: zero or one extensions.
+	if len(v) <= 1 {
+		for _, e := range v {
+			o.buf = append(o.buf, e.enc...)
+		}
+		return nil
+	}
+
+	// Sort keys to provide a deterministic encoding.
+	keys := make([]int, 0, len(v))
+	for k := range v {
+		keys = append(keys, int(k))
+	}
+	sort.Ints(keys)
+
+	for _, k := range keys {
+		o.buf = append(o.buf, v[int32(k)].enc...)
+	}
+	return nil
+}
+
+func size_map(p *Properties, base structPointer) int {
+	v := structPointer_ExtMap(base, p.field)
+	return extensionsMapSize(*v)
+}
+
+func size_exts(p *Properties, base structPointer) int {
+	v := structPointer_Extensions(base, p.field)
+	return extensionsSize(v)
+}
+
+// Encode a map field.
+func (o *Buffer) enc_new_map(p *Properties, base structPointer) error {
+	var state errorState // XXX: or do we need to plumb this through?
+
+	/*
+		A map defined as
+			map<key_type, value_type> map_field = N;
+		is encoded in the same way as
+			message MapFieldEntry {
+				key_type key = 1;
+				value_type value = 2;
+			}
+			repeated MapFieldEntry map_field = N;
+	*/
+
+	v := structPointer_NewAt(base, p.field, p.mtype).Elem() // map[K]V
+	if v.Len() == 0 {
+		return nil
+	}
+
+	keycopy, valcopy, keybase, valbase := mapEncodeScratch(p.mtype)
+
+	enc := func() error {
+		if err := p.mkeyprop.enc(o, p.mkeyprop, keybase); err != nil {
+			return err
+		}
+		if err := p.mvalprop.enc(o, p.mvalprop, valbase); err != nil && err != ErrNil {
+			return err
+		}
+		return nil
+	}
+
+	// Don't sort map keys. It is not required by the spec, and C++ doesn't do it.
+	for _, key := range v.MapKeys() {
+		val := v.MapIndex(key)
+
+		keycopy.Set(key)
+		valcopy.Set(val)
+
+		o.buf = append(o.buf, p.tagcode...)
+		if err := o.enc_len_thing(enc, &state); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func size_new_map(p *Properties, base structPointer) int {
+	v := structPointer_NewAt(base, p.field, p.mtype).Elem() // map[K]V
+
+	keycopy, valcopy, keybase, valbase := mapEncodeScratch(p.mtype)
+
+	n := 0
+	for _, key := range v.MapKeys() {
+		val := v.MapIndex(key)
+		keycopy.Set(key)
+		valcopy.Set(val)
+
+		// Tag codes for key and val are the responsibility of the sub-sizer.
+		keysize := p.mkeyprop.size(p.mkeyprop, keybase)
+		valsize := p.mvalprop.size(p.mvalprop, valbase)
+		entry := keysize + valsize
+		// Add on tag code and length of map entry itself.
+		n += len(p.tagcode) + sizeVarint(uint64(entry)) + entry
+	}
+	return n
+}
+
+// mapEncodeScratch returns a new reflect.Value matching the map's value type,
+// and a structPointer suitable for passing to an encoder or sizer.
+func mapEncodeScratch(mapType reflect.Type) (keycopy, valcopy reflect.Value, keybase, valbase structPointer) {
+	// Prepare addressable doubly-indirect placeholders for the key and value types.
+	// This is needed because the element-type encoders expect **T, but the map iteration produces T.
+
+	keycopy = reflect.New(mapType.Key()).Elem()                 // addressable K
+	keyptr := reflect.New(reflect.PtrTo(keycopy.Type())).Elem() // addressable *K
+	keyptr.Set(keycopy.Addr())                                  //
+	keybase = toStructPointer(keyptr.Addr())                    // **K
+
+	// Value types are more varied and require special handling.
+	switch mapType.Elem().Kind() {
+	case reflect.Slice:
+		// []byte
+		var dummy []byte
+		valcopy = reflect.ValueOf(&dummy).Elem() // addressable []byte
+		valbase = toStructPointer(valcopy.Addr())
+	case reflect.Ptr:
+		// message; the generated field type is map[K]*Msg (so V is *Msg),
+		// so we only need one level of indirection.
+		valcopy = reflect.New(mapType.Elem()).Elem() // addressable V
+		valbase = toStructPointer(valcopy.Addr())
+	default:
+		// everything else
+		valcopy = reflect.New(mapType.Elem()).Elem()                // addressable V
+		valptr := reflect.New(reflect.PtrTo(valcopy.Type())).Elem() // addressable *V
+		valptr.Set(valcopy.Addr())                                  //
+		valbase = toStructPointer(valptr.Addr())                    // **V
+	}
+	return
+}
+
+// Encode a struct.
+func (o *Buffer) enc_struct(prop *StructProperties, base structPointer) error {
+	var state errorState
+	// Encode fields in tag order so that decoders may use optimizations
+	// that depend on the ordering.
+	// https://developers.google.com/protocol-buffers/docs/encoding#order
+	for _, i := range prop.order {
+		p := prop.Prop[i]
+		if p.enc != nil {
+			err := p.enc(o, p, base)
+			if err != nil {
+				if err == ErrNil {
+					if p.Required && state.err == nil {
+						state.err = &RequiredNotSetError{p.Name}
+					}
+				} else if err == errRepeatedHasNil {
+					// Give more context to nil values in repeated fields.
+					return errors.New("repeated field " + p.OrigName + " has nil element")
+				} else if !state.shouldContinue(err, p) {
+					return err
+				}
+			}
+			if len(o.buf) > maxMarshalSize {
+				return ErrTooLarge
+			}
+		}
+	}
+
+	// Do oneof fields.
+	if prop.oneofMarshaler != nil {
+		m := structPointer_Interface(base, prop.stype).(Message)
+		if err := prop.oneofMarshaler(m, o); err == ErrNil {
+			return errOneofHasNil
+		} else if err != nil {
+			return err
+		}
+	}
+
+	// Add unrecognized fields at the end.
+	if prop.unrecField.IsValid() {
+		v := *structPointer_Bytes(base, prop.unrecField)
+		if len(o.buf)+len(v) > maxMarshalSize {
+			return ErrTooLarge
+		}
+		if len(v) > 0 {
+			o.buf = append(o.buf, v...)
+		}
+	}
+
+	return state.err
+}
+
+func size_struct(prop *StructProperties, base structPointer) (n int) {
+	for _, i := range prop.order {
+		p := prop.Prop[i]
+		if p.size != nil {
+			n += p.size(p, base)
+		}
+	}
+
+	// Add unrecognized fields at the end.
+	if prop.unrecField.IsValid() {
+		v := *structPointer_Bytes(base, prop.unrecField)
+		n += len(v)
+	}
+
+	// Factor in any oneof fields.
+	if prop.oneofSizer != nil {
+		m := structPointer_Interface(base, prop.stype).(Message)
+		n += prop.oneofSizer(m)
+	}
+
+	return
+}
+
+var zeroes [20]byte // longer than any conceivable sizeVarint
+
+// Encode a struct, preceded by its encoded length (as a varint).
+func (o *Buffer) enc_len_struct(prop *StructProperties, base structPointer, state *errorState) error {
+	return o.enc_len_thing(func() error { return o.enc_struct(prop, base) }, state)
+}
+
+// Encode something, preceded by its encoded length (as a varint).
+func (o *Buffer) enc_len_thing(enc func() error, state *errorState) error {
+	iLen := len(o.buf)
+	o.buf = append(o.buf, 0, 0, 0, 0) // reserve four bytes for length
+	iMsg := len(o.buf)
+	err := enc()
+	if err != nil && !state.shouldContinue(err, nil) {
+		return err
+	}
+	lMsg := len(o.buf) - iMsg
+	lLen := sizeVarint(uint64(lMsg))
+	switch x := lLen - (iMsg - iLen); {
+	case x > 0: // actual length is x bytes larger than the space we reserved
+		// Move msg x bytes right.
+		o.buf = append(o.buf, zeroes[:x]...)
+		copy(o.buf[iMsg+x:], o.buf[iMsg:iMsg+lMsg])
+	case x < 0: // actual length is x bytes smaller than the space we reserved
+		// Move msg x bytes left.
+		copy(o.buf[iMsg+x:], o.buf[iMsg:iMsg+lMsg])
+		o.buf = o.buf[:len(o.buf)+x] // x is negative
+	}
+	// Encode the length in the reserved space.
+	o.buf = o.buf[:iLen]
+	o.EncodeVarint(uint64(lMsg))
+	o.buf = o.buf[:len(o.buf)+lMsg]
+	return state.err
+}
+
+// errorState maintains the first error that occurs and updates that error
+// with additional context.
+type errorState struct {
+	err error
+}
+
+// shouldContinue reports whether encoding should continue upon encountering the
+// given error. If the error is RequiredNotSetError, shouldContinue returns true
+// and, if this is the first appearance of that error, remembers it for future
+// reporting.
+//
+// If prop is not nil, it may update any error with additional context about the
+// field with the error.
+func (s *errorState) shouldContinue(err error, prop *Properties) bool {
+	// Ignore unset required fields.
+	reqNotSet, ok := err.(*RequiredNotSetError)
+	if !ok {
+		return false
+	}
+	if s.err == nil {
+		if prop != nil {
+			err = &RequiredNotSetError{prop.Name + "." + reqNotSet.field}
+		}
+		s.err = err
+	}
+	return true
+}

go/vendor/github.com/golang/protobuf/proto/equal.go

+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2011 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.
+
+// Protocol buffer comparison.
+
+package proto
+
+import (
+	"bytes"
+	"log"
+	"reflect"
+	"strings"
+)
+
+/*
+Equal returns true iff protocol buffers a and b are equal.
+The arguments must both be pointers to protocol buffer structs.
+
+Equality is defined in this way:
+  - Two messages are equal iff they are the same type,
+    corresponding fields are equal, unknown field sets
+    are equal, and extensions sets are equal.
+  - Two set scalar fields are equal iff their values are equal.
+    If the fields are of a floating-point type, remember that
+    NaN != x for all x, including NaN. If the message is defined
+    in a proto3 .proto file, fields are not "set"; specifically,
+    zero length proto3 "bytes" fields are equal (nil == {}).
+  - Two repeated fields are equal iff their lengths are the same,
+    and their corresponding elements are equal. Note a "bytes" field,
+    although represented by []byte, is not a repeated field and the
+    rule for the scalar fields described above applies.
+  - Two unset fields are equal.
+  - Two unknown field sets are equal if their current
+    encoded state is equal.
+  - Two extension sets are equal iff they have corresponding
+    elements that are pairwise equal.
+  - Two map fields are equal iff their lengths are the same,
+    and they contain the same set of elements. Zero-length map
+    fields are equal.
+  - Every other combination of things are not equal.
+
+The return value is undefined if a and b are not protocol buffers.
+*/
+func Equal(a, b Message) bool {
+	if a == nil || b == nil {
+		return a == b
+	}
+	v1, v2 := reflect.ValueOf(a), reflect.ValueOf(b)
+	if v1.Type() != v2.Type() {
+		return false
+	}
+	if v1.Kind() == reflect.Ptr {
+		if v1.IsNil() {
+			return v2.IsNil()
+		}
+		if v2.IsNil() {
+			return false
+		}
+		v1, v2 = v1.Elem(), v2.Elem()
+	}
+	if v1.Kind() != reflect.Struct {
+		return false
+	}
+	return equalStruct(v1, v2)
+}
+
+// v1 and v2 are known to have the same type.
+func equalStruct(v1, v2 reflect.Value) bool {
+	sprop := GetProperties(v1.Type())
+	for i := 0; i < v1.NumField(); i++ {
+		f := v1.Type().Field(i)
+		if strings.HasPrefix(f.Name, "XXX_") {
+			continue
+		}
+		f1, f2 := v1.Field(i), v2.Field(i)
+		if f.Type.Kind() == reflect.Ptr {
+			if n1, n2 := f1.IsNil(), f2.IsNil(); n1 && n2 {
+				// both unset
+				continue
+			} else if n1 != n2 {
+				// set/unset mismatch
+				return false
+			}
+			b1, ok := f1.Interface().(raw)
+			if ok {
+				b2 := f2.Interface().(raw)
+				// RawMessage
+				if !bytes.Equal(b1.Bytes(), b2.Bytes()) {
+					return false
+				}
+				continue
+			}
+			f1, f2 = f1.Elem(), f2.Elem()
+		}
+		if !equalAny(f1, f2, sprop.Prop[i]) {
+			return false
+		}
+	}
+
+	if em1 := v1.FieldByName("XXX_InternalExtensions"); em1.IsValid() {
+		em2 := v2.FieldByName("XXX_InternalExtensions")
+		if !equalExtensions(v1.Type(), em1.Interface().(XXX_InternalExtensions), em2.Interface().(XXX_InternalExtensions)) {
+			return false
+		}
+	}
+
+	if em1 := v1.FieldByName("XXX_extensions"); em1.IsValid() {
+		em2 := v2.FieldByName("XXX_extensions")
+		if !equalExtMap(v1.Type(), em1.Interface().(map[int32]Extension), em2.Interface().(map[int32]Extension)) {
+			return false
+		}
+	}
+
+	uf := v1.FieldByName("XXX_unrecognized")
+	if !uf.IsValid() {
+		return true
+	}
+
+	u1 := uf.Bytes()
+	u2 := v2.FieldByName("XXX_unrecognized").Bytes()
+	if !bytes.Equal(u1, u2) {
+		return false
+	}
+
+	return true
+}
+
+// v1 and v2 are known to have the same type.
+// prop may be nil.
+func equalAny(v1, v2 reflect.Value, prop *Properties) bool {
+	if v1.Type() == protoMessageType {
+		m1, _ := v1.Interface().(Message)
+		m2, _ := v2.Interface().(Message)
+		return Equal(m1, m2)
+	}
+	switch v1.Kind() {
+	case reflect.Bool:
+		return v1.Bool() == v2.Bool()
+	case reflect.Float32, reflect.Float64:
+		return v1.Float() == v2.Float()
+	case reflect.Int32, reflect.Int64:
+		return v1.Int() == v2.Int()
+	case reflect.Interface:
+		// Probably a oneof field; compare the inner values.
+		n1, n2 := v1.IsNil(), v2.IsNil()
+		if n1 || n2 {
+			return n1 == n2
+		}
+		e1, e2 := v1.Elem(), v2.Elem()
+		if e1.Type() != e2.Type() {
+			return false
+		}
+		return equalAny(e1, e2, nil)
+	case reflect.Map:
+		if v1.Len() != v2.Len() {
+			return false
+		}
+		for _, key := range v1.MapKeys() {
+			val2 := v2.MapIndex(key)
+			if !val2.IsValid() {
+				// This key was not found in the second map.
+				return false
+			}
+			if !equalAny(v1.MapIndex(key), val2, nil) {
+				return false
+			}
+		}
+		return true
+	case reflect.Ptr:
+		// Maps may have nil values in them, so check for nil.
+		if v1.IsNil() && v2.IsNil() {
+			return true
+		}
+		if v1.IsNil() != v2.IsNil() {
+			return false
+		}
+		return equalAny(v1.Elem(), v2.Elem(), prop)
+	case reflect.Slice:
+		if v1.Type().Elem().Kind() == reflect.Uint8 {
+			// short circuit: []byte
+
+			// Edge case: if this is in a proto3 message, a zero length
+			// bytes field is considered the zero value.
+			if prop != nil && prop.proto3 && v1.Len() == 0 && v2.Len() == 0 {
+				return true
+			}
+			if v1.IsNil() != v2.IsNil() {
+				return false
+			}
+			return bytes.Equal(v1.Interface().([]byte), v2.Interface().([]byte))
+		}
+
+		if v1.Len() != v2.Len() {
+			return false
+		}
+		for i := 0; i < v1.Len(); i++ {
+			if !equalAny(v1.Index(i), v2.Index(i), prop) {
+				return false
+			}
+		}
+		return true
+	case reflect.String:
+		return v1.Interface().(string) == v2.Interface().(string)
+	case reflect.Struct:
+		return equalStruct(v1, v2)
+	case reflect.Uint32, reflect.Uint64:
+		return v1.Uint() == v2.Uint()
+	}
+
+	// unknown type, so not a protocol buffer
+	log.Printf("proto: don't know how to compare %v", v1)
+	return false
+}
+
+// base is the struct type that the extensions are based on.
+// x1 and x2 are InternalExtensions.
+func equalExtensions(base reflect.Type, x1, x2 XXX_InternalExtensions) bool {
+	em1, _ := x1.extensionsRead()
+	em2, _ := x2.extensionsRead()
+	return equalExtMap(base, em1, em2)
+}
+
+func equalExtMap(base reflect.Type, em1, em2 map[int32]Extension) bool {
+	if len(em1) != len(em2) {
+		return false
+	}
+
+	for extNum, e1 := range em1 {
+		e2, ok := em2[extNum]
+		if !ok {
+			return false
+		}
+
+		m1, m2 := e1.value, e2.value
+
+		if m1 != nil && m2 != nil {
+			// Both are unencoded.
+			if !equalAny(reflect.ValueOf(m1), reflect.ValueOf(m2), nil) {
+				return false
+			}
+			continue
+		}
+
+		// At least one is encoded. To do a semantically correct comparison
+		// we need to unmarshal them first.
+		var desc *ExtensionDesc
+		if m := extensionMaps[base]; m != nil {
+			desc = m[extNum]
+		}
+		if desc == nil {
+			log.Printf("proto: don't know how to compare extension %d of %v", extNum, base)
+			continue
+		}
+		var err error
+		if m1 == nil {
+			m1, err = decodeExtension(e1.enc, desc)
+		}
+		if m2 == nil && err == nil {
+			m2, err = decodeExtension(e2.enc, desc)
+		}
+		if err != nil {
+			// The encoded form is invalid.
+			log.Printf("proto: badly encoded extension %d of %v: %v", extNum, base, err)
+			return false
+		}
+		if !equalAny(reflect.ValueOf(m1), reflect.ValueOf(m2), nil) {
+			return false
+		}
+	}
+
+	return true
+}

go/vendor/github.com/golang/protobuf/proto/extensions.go

+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2010 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
+
+/*
+ * Types and routines for supporting protocol buffer extensions.
+ */
+
+import (
+	"errors"
+	"fmt"
+	"reflect"
+	"strconv"
+	"sync"
+)
+
+// ErrMissingExtension is the error returned by GetExtension if the named extension is not in the message.
+var ErrMissingExtension = errors.New("proto: missing extension")
+
+// ExtensionRange represents a range of message extensions for a protocol buffer.
+// Used in code generated by the protocol compiler.
+type ExtensionRange struct {
+	Start, End int32 // both inclusive
+}
+
+// extendableProto is an interface implemented by any protocol buffer generated by the current
+// proto compiler that may be extended.
+type extendableProto interface {
+	Message
+	ExtensionRangeArray() []ExtensionRange
+	extensionsWrite() map[int32]Extension
+	extensionsRead() (map[int32]Extension, sync.Locker)
+}
+
+// extendableProtoV1 is an interface implemented by a protocol buffer generated by the previous
+// version of the proto compiler that may be extended.
+type extendableProtoV1 interface {
+	Message
+	ExtensionRangeArray() []ExtensionRange
+	ExtensionMap() map[int32]Extension
+}
+
+// extensionAdapter is a wrapper around extendableProtoV1 that implements extendableProto.
+type extensionAdapter struct {
+	extendableProtoV1
+}
+
+func (e extensionAdapter) extensionsWrite() map[int32]Extension {
+	return e.ExtensionMap()
+}
+
+func (e extensionAdapter) extensionsRead() (map[int32]Extension, sync.Locker) {
+	return e.ExtensionMap(), notLocker{}
+}
+
+// notLocker is a sync.Locker whose Lock and Unlock methods are nops.
+type notLocker struct{}
+
+func (n notLocker) Lock()   {}
+func (n notLocker) Unlock() {}
+
+// extendable returns the extendableProto interface for the given generated proto message.
+// If the proto message has the old extension format, it returns a wrapper that implements
+// the extendableProto interface.
+func extendable(p interface{}) (extendableProto, bool) {
+	if ep, ok := p.(extendableProto); ok {
+		return ep, ok
+	}
+	if ep, ok := p.(extendableProtoV1); ok {
+		return extensionAdapter{ep}, ok
+	}
+	return nil, false
+}
+
+// XXX_InternalExtensions is an internal representation of proto extensions.
+//
+// Each generated message struct type embeds an anonymous XXX_InternalExtensions field,
+// thus gaining the unexported 'extensions' method, which can be called only from the proto package.
+//
+// The methods of XXX_InternalExtensions are not concurrency safe in general,
+// but calls to logically read-only methods such as has and get may be executed concurrently.
+type XXX_InternalExtensions struct {
+	// The struct must be indirect so that if a user inadvertently copies a
+	// generated message and its embedded XXX_InternalExtensions, they
+	// avoid the mayhem of a copied mutex.
+	//
+	// The mutex serializes all logically read-only operations to p.extensionMap.
+	// It is up to the client to ensure that write operations to p.extensionMap are
+	// mutually exclusive with other accesses.
+	p *struct {
+		mu           sync.Mutex
+		extensionMap map[int32]Extension
+	}
+}
+
+// extensionsWrite returns the extension map, creating it on first use.
+func (e *XXX_InternalExtensions) extensionsWrite() map[int32]Extension {
+	if e.p == nil {
+		e.p = new(struct {
+			mu           sync.Mutex
+			extensionMap map[int32]Extension
+		})
+		e.p.extensionMap = make(map[int32]Extension)
+	}
+	return e.p.extensionMap
+}
+
+// extensionsRead returns the extensions map for read-only use.  It may be nil.
+// The caller must hold the returned mutex's lock when accessing Elements within the map.
+func (e *XXX_InternalExtensions) extensionsRead() (map[int32]Extension, sync.Locker) {
+	if e.p == nil {
+		return nil, nil
+	}
+	return e.p.extensionMap, &e.p.mu
+}
+
+var extendableProtoType = reflect.TypeOf((*extendableProto)(nil)).Elem()
+var extendableProtoV1Type = reflect.TypeOf((*extendableProtoV1)(nil)).Elem()
+
+// ExtensionDesc represents an extension specification.
+// Used in generated code from the protocol compiler.
+type ExtensionDesc struct {
+	ExtendedType  Message     // nil pointer to the type that is being extended
+	ExtensionType interface{} // nil pointer to the extension type
+	Field         int32       // field number
+	Name          string      // fully-qualified name of extension, for text formatting
+	Tag           string      // protobuf tag style
+	Filename      string      // name of the file in which the extension is defined
+}
+
+func (ed *ExtensionDesc) repeated() bool {
+	t := reflect.TypeOf(ed.ExtensionType)
+	return t.Kind() == reflect.Slice && t.Elem().Kind() != reflect.Uint8
+}
+
+// Extension represents an extension in a message.
+type Extension struct {
+	// When an extension is stored in a message using SetExtension
+	// only desc and value are set. When the message is marshaled
+	// enc will be set to the encoded form of the message.
+	//
+	// When a message is unmarshaled and contains extensions, each
+	// extension will have only enc set. When such an extension is
+	// accessed using GetExtension (or GetExtensions) desc and value
+	// will be set.
+	desc  *ExtensionDesc
+	value interface{}
+	enc   []byte
+}
+
+// SetRawExtension is for testing only.
+func SetRawExtension(base Message, id int32, b []byte) {
+	epb, ok := extendable(base)
+	if !ok {
+		return
+	}
+	extmap := epb.extensionsWrite()
+	extmap[id] = Extension{enc: b}
+}
+
+// isExtensionField returns true iff the given field number is in an extension range.
+func isExtensionField(pb extendableProto, field int32) bool {
+	for _, er := range pb.ExtensionRangeArray() {
+		if er.Start <= field && field <= er.End {
+			return true
+		}
+	}
+	return false
+}
+
+// checkExtensionTypes checks that the given extension is valid for pb.
+func checkExtensionTypes(pb extendableProto, extension *ExtensionDesc) error {
+	var pbi interface{} = pb
+	// Check the extended type.
+	if ea, ok := pbi.(extensionAdapter); ok {
+		pbi = ea.extendableProtoV1
+	}
+	if a, b := reflect.TypeOf(pbi), reflect.TypeOf(extension.ExtendedType); a != b {
+		return errors.New("proto: bad extended type; " + b.String() + " does not extend " + a.String())
+	}
+	// Check the range.
+	if !isExtensionField(pb, extension.Field) {
+		return errors.New("proto: bad extension number; not in declared ranges")
+	}
+	return nil
+}
+
+// extPropKey is sufficient to uniquely identify an extension.
+type extPropKey struct {
+	base  reflect.Type
+	field int32
+}
+
+var extProp = struct {
+	sync.RWMutex
+	m map[extPropKey]*Properties
+}{
+	m: make(map[extPropKey]*Properties),
+}
+
+func extensionProperties(ed *ExtensionDesc) *Properties {
+	key := extPropKey{base: reflect.TypeOf(ed.ExtendedType), field: ed.Field}
+
+	extProp.RLock()
+	if prop, ok := extProp.m[key]; ok {
+		extProp.RUnlock()
+		return prop
+	}
+	extProp.RUnlock()
+
+	extProp.Lock()
+	defer extProp.Unlock()
+	// Check again.
+	if prop, ok := extProp.m[key]; ok {
+		return prop
+	}
+
+	prop := new(Properties)
+	prop.Init(reflect.TypeOf(ed.ExtensionType), "unknown_name", ed.Tag, nil)
+	extProp.m[key] = prop
+	return prop
+}
+
+// encode encodes any unmarshaled (unencoded) extensions in e.
+func encodeExtensions(e *XXX_InternalExtensions) error {
+	m, mu := e.extensionsRead()
+	if m == nil {
+		return nil // fast path
+	}
+	mu.Lock()
+	defer mu.Unlock()
+	return encodeExtensionsMap(m)
+}
+
+// encode encodes any unmarshaled (unencoded) extensions in e.
+func encodeExtensionsMap(m map[int32]Extension) error {
+	for k, e := range m {
+		if e.value == nil || e.desc == nil {
+			// Extension is only in its encoded form.
+			continue
+		}
+
+		// We don't skip extensions that have an encoded form set,
+		// because the extension value may have been mutated after
+		// the last time this function was called.
+
+		et := reflect.TypeOf(e.desc.ExtensionType)
+		props := extensionProperties(e.desc)
+
+		p := NewBuffer(nil)
+		// If e.value has type T, the encoder expects a *struct{ X T }.
+		// Pass a *T with a zero field and hope it all works out.
+		x := reflect.New(et)
+		x.Elem().Set(reflect.ValueOf(e.value))
+		if err := props.enc(p, props, toStructPointer(x)); err != nil {
+			return err
+		}
+		e.enc = p.buf
+		m[k] = e
+	}
+	return nil
+}
+
+func extensionsSize(e *XXX_InternalExtensions) (n int) {
+	m, mu := e.extensionsRead()
+	if m == nil {
+		return 0
+	}
+	mu.Lock()
+	defer mu.Unlock()
+	return extensionsMapSize(m)
+}
+
+func extensionsMapSize(m map[int32]Extension) (n int) {
+	for _, e := range m {
+		if e.value == nil || e.desc == nil {
+			// Extension is only in its encoded form.
+			n += len(e.enc)
+			continue
+		}
+
+		// We don't skip extensions that have an encoded form set,
+		// because the extension value may have been mutated after
+		// the last time this function was called.
+
+		et := reflect.TypeOf(e.desc.ExtensionType)
+		props := extensionProperties(e.desc)
+
+		// If e.value has type T, the encoder expects a *struct{ X T }.
+		// Pass a *T with a zero field and hope it all works out.
+		x := reflect.New(et)
+		x.Elem().Set(reflect.ValueOf(e.value))
+		n += props.size(props, toStructPointer(x))
+	}
+	return
+}
+
+// HasExtension returns whether the given extension is present in pb.
+func HasExtension(pb Message, extension *ExtensionDesc) bool {
+	// TODO: Check types, field numbers, etc.?
+	epb, ok := extendable(pb)
+	if !ok {
+		return false
+	}
+	extmap, mu := epb.extensionsRead()
+	if extmap == nil {
+		return false
+	}
+	mu.Lock()
+	_, ok = extmap[extension.Field]
+	mu.Unlock()
+	return ok
+}
+
+// ClearExtension removes the given extension from pb.
+func ClearExtension(pb Message, extension *ExtensionDesc) {
+	epb, ok := extendable(pb)
+	if !ok {
+		return
+	}
+	// TODO: Check types, field numbers, etc.?
+	extmap := epb.extensionsWrite()
+	delete(extmap, extension.Field)
+}
+
+// GetExtension parses and returns the given extension of pb.
+// If the extension is not present and has no default value it returns ErrMissingExtension.
+func GetExtension(pb Message, extension *ExtensionDesc) (interface{}, error) {
+	epb, ok := extendable(pb)
+	if !ok {
+		return nil, errors.New("proto: not an extendable proto")
+	}
+
+	if err := checkExtensionTypes(epb, extension); err != nil {
+		return nil, err
+	}
+
+	emap, mu := epb.extensionsRead()
+	if emap == nil {
+		return defaultExtensionValue(extension)
+	}
+	mu.Lock()
+	defer mu.Unlock()
+	e, ok := emap[extension.Field]
+	if !ok {
+		// defaultExtensionValue returns the default value or
+		// ErrMissingExtension if there is no default.
+		return defaultExtensionValue(extension)
+	}
+
+	if e.value != nil {
+		// Already decoded. Check the descriptor, though.
+		if e.desc != extension {
+			// This shouldn't happen. If it does, it means that
+			// GetExtension was called twice with two different
+			// descriptors with the same field number.
+			return nil, errors.New("proto: descriptor conflict")
+		}
+		return e.value, nil
+	}
+
+	v, err := decodeExtension(e.enc, extension)
+	if err != nil {
+		return nil, err
+	}
+
+	// Remember the decoded version and drop the encoded version.
+	// That way it is safe to mutate what we return.
+	e.value = v
+	e.desc = extension
+	e.enc = nil
+	emap[extension.Field] = e
+	return e.value, nil
+}
+
+// defaultExtensionValue returns the default value for extension.
+// If no default for an extension is defined ErrMissingExtension is returned.
+func defaultExtensionValue(extension *ExtensionDesc) (interface{}, error) {
+	t := reflect.TypeOf(extension.ExtensionType)
+	props := extensionProperties(extension)
+
+	sf, _, err := fieldDefault(t, props)
+	if err != nil {
+		return nil, err
+	}
+
+	if sf == nil || sf.value == nil {
+		// There is no default value.
+		return nil, ErrMissingExtension
+	}
+
+	if t.Kind() != reflect.Ptr {
+		// We do not need to return a Ptr, we can directly return sf.value.
+		return sf.value, nil
+	}
+
+	// We need to return an interface{} that is a pointer to sf.value.
+	value := reflect.New(t).Elem()
+	value.Set(reflect.New(value.Type().Elem()))
+	if sf.kind == reflect.Int32 {
+		// We may have an int32 or an enum, but the underlying data is int32.
+		// Since we can't set an int32 into a non int32 reflect.value directly
+		// set it as a int32.
+		value.Elem().SetInt(int64(sf.value.(int32)))
+	} else {
+		value.Elem().Set(reflect.ValueOf(sf.value))
+	}
+	return value.Interface(), nil
+}
+
+// decodeExtension decodes an extension encoded in b.
+func decodeExtension(b []byte, extension *ExtensionDesc) (interface{}, error) {
+	o := NewBuffer(b)
+
+	t := reflect.TypeOf(extension.ExtensionType)
+
+	props := extensionProperties(extension)
+
+	// t is a pointer to a struct, pointer to basic type or a slice.
+	// Allocate a "field" to store the pointer/slice itself; the
+	// pointer/slice will be stored here. We pass
+	// the address of this field to props.dec.
+	// This passes a zero field and a *t and lets props.dec
+	// interpret it as a *struct{ x t }.
+	value := reflect.New(t).Elem()
+
+	for {
+		// Discard wire type and field number varint. It isn't needed.
+		if _, err := o.DecodeVarint(); err != nil {
+			return nil, err
+		}
+
+		if err := props.dec(o, props, toStructPointer(value.Addr())); err != nil {
+			return nil, err
+		}
+
+		if o.index >= len(o.buf) {
+			break
+		}
+	}
+	return value.Interface(), nil
+}
+
+// GetExtensions returns a slice of the extensions present in pb that are also listed in es.
+// The returned slice has the same length as es; missing extensions will appear as nil elements.
+func GetExtensions(pb Message, es []*ExtensionDesc) (extensions []interface{}, err error) {
+	epb, ok := extendable(pb)
+	if !ok {
+		return nil, errors.New("proto: not an extendable proto")
+	}
+	extensions = make([]interface{}, len(es))
+	for i, e := range es {
+		extensions[i], err = GetExtension(epb, e)
+		if err == ErrMissingExtension {
+			err = nil
+		}
+		if err != nil {
+			return
+		}
+	}
+	return
+}
+
+// ExtensionDescs returns a new slice containing pb's extension descriptors, in undefined order.
+// For non-registered extensions, ExtensionDescs returns an incomplete descriptor containing
+// just the Field field, which defines the extension's field number.
+func ExtensionDescs(pb Message) ([]*ExtensionDesc, error) {
+	epb, ok := extendable(pb)
+	if !ok {
+		return nil, fmt.Errorf("proto: %T is not an extendable proto.Message", pb)
+	}
+	registeredExtensions := RegisteredExtensions(pb)
+
+	emap, mu := epb.extensionsRead()
+	if emap == nil {
+		return nil, nil
+	}
+	mu.Lock()
+	defer mu.Unlock()
+	extensions := make([]*ExtensionDesc, 0, len(emap))
+	for extid, e := range emap {
+		desc := e.desc
+		if desc == nil {
+			desc = registeredExtensions[extid]
+			if desc == nil {
+				desc = &ExtensionDesc{Field: extid}
+			}
+		}
+
+		extensions = append(extensions, desc)
+	}
+	return extensions, nil
+}
+
+// SetExtension sets the specified extension of pb to the specified value.
+func SetExtension(pb Message, extension *ExtensionDesc, value interface{}) error {
+	epb, ok := extendable(pb)
+	if !ok {
+		return errors.New("proto: not an extendable proto")
+	}
+	if err := checkExtensionTypes(epb, extension); err != nil {
+		return err
+	}
+	typ := reflect.TypeOf(extension.ExtensionType)
+	if typ != reflect.TypeOf(value) {
+		return errors.New("proto: bad extension value type")
+	}
+	// nil extension values need to be caught early, because the
+	// encoder can't distinguish an ErrNil due to a nil extension
+	// from an ErrNil due to a missing field. Extensions are
+	// always optional, so the encoder would just swallow the error
+	// and drop all the extensions from the encoded message.
+	if reflect.ValueOf(value).IsNil() {
+		return fmt.Errorf("proto: SetExtension called with nil value of type %T", value)
+	}
+
+	extmap := epb.extensionsWrite()
+	extmap[extension.Field] = Extension{desc: extension, value: value}
+	return nil
+}
+
+// ClearAllExtensions clears all extensions from pb.
+func ClearAllExtensions(pb Message) {
+	epb, ok := extendable(pb)
+	if !ok {
+		return
+	}
+	m := epb.extensionsWrite()
+	for k := range m {
+		delete(m, k)
+	}
+}
+
+// A global registry of extensions.
+// The generated code will register the generated descriptors by calling RegisterExtension.
+
+var extensionMaps = make(map[reflect.Type]map[int32]*ExtensionDesc)
+
+// RegisterExtension is called from the generated code.
+func RegisterExtension(desc *ExtensionDesc) {
+	st := reflect.TypeOf(desc.ExtendedType).Elem()
+	m := extensionMaps[st]
+	if m == nil {
+		m = make(map[int32]*ExtensionDesc)
+		extensionMaps[st] = m
+	}
+	if _, ok := m[desc.Field]; ok {
+		panic("proto: duplicate extension registered: " + st.String() + " " + strconv.Itoa(int(desc.Field)))
+	}
+	m[desc.Field] = desc
+}
+
+// RegisteredExtensions returns a map of the registered extensions of a
+// protocol buffer struct, indexed by the extension number.
+// The argument pb should be a nil pointer to the struct type.
+func RegisteredExtensions(pb Message) map[int32]*ExtensionDesc {
+	return extensionMaps[reflect.TypeOf(pb).Elem()]
+}

go/vendor/github.com/golang/protobuf/proto/lib.go

+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2010 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 converts data structures to and from the wire format of
+protocol buffers.  It works in concert with the Go source code generated
+for .proto files by the protocol compiler.
+
+A summary of the properties of the protocol buffer interface
+for a protocol buffer variable v:
+
+  - Names are turned from camel_case to CamelCase for export.
+  - There are no methods on v to set fields; just treat
+	them as structure fields.
+  - There are getters that return a field's value if set,
+	and return the field's default value if unset.
+	The getters work even if the receiver is a nil message.
+  - The zero value for a struct is its correct initialization state.
+	All desired fields must be set before marshaling.
+  - A Reset() method will restore a protobuf struct to its zero state.
+  - Non-repeated fields are pointers to the values; nil means unset.
+	That is, optional or required field int32 f becomes F *int32.
+  - Repeated fields are slices.
+  - Helper functions are available to aid the setting of fields.
+	msg.Foo = proto.String("hello") // set field
+  - Constants are defined to hold the default values of all fields that
+	have them.  They have the form Default_StructName_FieldName.
+	Because the getter methods handle defaulted values,
+	direct use of these constants should be rare.
+  - Enums are given type names and maps from names to values.
+	Enum values are prefixed by the enclosing message's name, or by the
+	enum's type name if it is a top-level enum. Enum types have a String
+	method, and a Enum method to assist in message construction.
+  - Nested messages, groups and enums have type names prefixed with the name of
+	the surrounding message type.
+  - Extensions are given descriptor names that start with E_,
+	followed by an underscore-delimited list of the nested messages
+	that contain it (if any) followed by the CamelCased name of the
+	extension field itself.  HasExtension, ClearExtension, GetExtension
+	and SetExtension are functions for manipulating extensions.
+  - Oneof field sets are given a single field in their message,
+	with distinguished wrapper types for each possible field value.
+  - Marshal and Unmarshal are functions to encode and decode the wire format.
+
+When the .proto file specifies `syntax="proto3"`, there are some differences:
+
+  - Non-repeated fields of non-message type are values instead of pointers.
+  - Getters are only generated for message and oneof fields.
+  - Enum types do not get an Enum method.
+
+The simplest way to describe this is to see an example.
+Given file test.proto, containing
+
+	package example;
+
+	enum FOO { X = 17; }
+
+	message Test {
+	  required string label = 1;
+	  optional int32 type = 2 [default=77];
+	  repeated int64 reps = 3;
+	  optional group OptionalGroup = 4 {
+	    required string RequiredField = 5;
+	  }
+	  oneof union {
+	    int32 number = 6;
+	    string name = 7;
+	  }
+	}
+
+The resulting file, test.pb.go, is:
+
+	package example
+
+	import proto "github.com/golang/protobuf/proto"
+	import math "math"
+
+	type FOO int32
+	const (
+		FOO_X FOO = 17
+	)
+	var FOO_name = map[int32]string{
+		17: "X",
+	}
+	var FOO_value = map[string]int32{
+		"X": 17,
+	}
+
+	func (x FOO) Enum() *FOO {
+		p := new(FOO)
+		*p = x
+		return p
+	}
+	func (x FOO) String() string {
+		return proto.EnumName(FOO_name, int32(x))
+	}
+	func (x *FOO) UnmarshalJSON(data []byte) error {
+		value, err := proto.UnmarshalJSONEnum(FOO_value, data)
+		if err != nil {
+			return err
+		}
+		*x = FOO(value)
+		return nil
+	}
+
+	type Test struct {
+		Label         *string             `protobuf:"bytes,1,req,name=label" json:"label,omitempty"`
+		Type          *int32              `protobuf:"varint,2,opt,name=type,def=77" json:"type,omitempty"`
+		Reps          []int64             `protobuf:"varint,3,rep,name=reps" json:"reps,omitempty"`
+		Optionalgroup *Test_OptionalGroup `protobuf:"group,4,opt,name=OptionalGroup" json:"optionalgroup,omitempty"`
+		// Types that are valid to be assigned to Union:
+		//	*Test_Number
+		//	*Test_Name
+		Union            isTest_Union `protobuf_oneof:"union"`
+		XXX_unrecognized []byte       `json:"-"`
+	}
+	func (m *Test) Reset()         { *m = Test{} }
+	func (m *Test) String() string { return proto.CompactTextString(m) }
+	func (*Test) ProtoMessage() {}
+
+	type isTest_Union interface {
+		isTest_Union()
+	}
+
+	type Test_Number struct {
+		Number int32 `protobuf:"varint,6,opt,name=number"`
+	}
+	type Test_Name struct {
+		Name string `protobuf:"bytes,7,opt,name=name"`
+	}
+
+	func (*Test_Number) isTest_Union() {}
+	func (*Test_Name) isTest_Union()   {}
+
+	func (m *Test) GetUnion() isTest_Union {
+		if m != nil {
+			return m.Union
+		}
+		return nil
+	}
+	const Default_Test_Type int32 = 77
+
+	func (m *Test) GetLabel() string {
+		if m != nil && m.Label != nil {
+			return *m.Label
+		}
+		return ""
+	}
+
+	func (m *Test) GetType() int32 {
+		if m != nil && m.Type != nil {
+			return *m.Type
+		}
+		return Default_Test_Type
+	}
+
+	func (m *Test) GetOptionalgroup() *Test_OptionalGroup {
+		if m != nil {
+			return m.Optionalgroup
+		}
+		return nil
+	}
+
+	type Test_OptionalGroup struct {
+		RequiredField *string `protobuf:"bytes,5,req" json:"RequiredField,omitempty"`
+	}
+	func (m *Test_OptionalGroup) Reset()         { *m = Test_OptionalGroup{} }
+	func (m *Test_OptionalGroup) String() string { return proto.CompactTextString(m) }
+
+	func (m *Test_OptionalGroup) GetRequiredField() string {
+		if m != nil && m.RequiredField != nil {
+			return *m.RequiredField
+		}
+		return ""
+	}
+
+	func (m *Test) GetNumber() int32 {
+		if x, ok := m.GetUnion().(*Test_Number); ok {
+			return x.Number
+		}
+		return 0
+	}
+
+	func (m *Test) GetName() string {
+		if x, ok := m.GetUnion().(*Test_Name); ok {
+			return x.Name
+		}
+		return ""
+	}
+
+	func init() {
+		proto.RegisterEnum("example.FOO", FOO_name, FOO_value)
+	}
+
+To create and play with a Test object:
+
+	package main
+
+	import (
+		"log"
+
+		"github.com/golang/protobuf/proto"
+		pb "./example.pb"
+	)
+
+	func main() {
+		test := &pb.Test{
+			Label: proto.String("hello"),
+			Type:  proto.Int32(17),
+			Reps:  []int64{1, 2, 3},
+			Optionalgroup: &pb.Test_OptionalGroup{
+				RequiredField: proto.String("good bye"),
+			},
+			Union: &pb.Test_Name{"fred"},
+		}
+		data, err := proto.Marshal(test)
+		if err != nil {
+			log.Fatal("marshaling error: ", err)
+		}
+		newTest := &pb.Test{}
+		err = proto.Unmarshal(data, newTest)
+		if err != nil {
+			log.Fatal("unmarshaling error: ", err)
+		}
+		// Now test and newTest contain the same data.
+		if test.GetLabel() != newTest.GetLabel() {
+			log.Fatalf("data mismatch %q != %q", test.GetLabel(), newTest.GetLabel())
+		}
+		// Use a type switch to determine which oneof was set.
+		switch u := test.Union.(type) {
+		case *pb.Test_Number: // u.Number contains the number.
+		case *pb.Test_Name: // u.Name contains the string.
+		}
+		// etc.
+	}
+*/
+package proto
+
+import (
+	"encoding/json"
+	"fmt"
+	"log"
+	"reflect"
+	"sort"
+	"strconv"
+	"sync"
+)
+
+// Message is implemented by generated protocol buffer messages.
+type Message interface {
+	Reset()
+	String() string
+	ProtoMessage()
+}
+
+// Stats records allocation details about the protocol buffer encoders
+// and decoders.  Useful for tuning the library itself.
+type Stats struct {
+	Emalloc uint64 // mallocs in encode
+	Dmalloc uint64 // mallocs in decode
+	Encode  uint64 // number of encodes
+	Decode  uint64 // number of decodes
+	Chit    uint64 // number of cache hits
+	Cmiss   uint64 // number of cache misses
+	Size    uint64 // number of sizes
+}
+
+// Set to true to enable stats collection.
+const collectStats = false
+
+var stats Stats
+
+// GetStats returns a copy of the global Stats structure.
+func GetStats() Stats { return stats }
+
+// A Buffer is a buffer manager for marshaling and unmarshaling
+// protocol buffers.  It may be reused between invocations to
+// reduce memory usage.  It is not necessary to use a Buffer;
+// the global functions Marshal and Unmarshal create a
+// temporary Buffer and are fine for most applications.
+type Buffer struct {
+	buf   []byte // encode/decode byte stream
+	index int    // read point
+
+	// pools of basic types to amortize allocation.
+	bools   []bool
+	uint32s []uint32
+	uint64s []uint64
+
+	// extra pools, only used with pointer_reflect.go
+	int32s   []int32
+	int64s   []int64
+	float32s []float32
+	float64s []float64
+}
+
+// NewBuffer allocates a new Buffer and initializes its internal data to
+// the contents of the argument slice.
+func NewBuffer(e []byte) *Buffer {
+	return &Buffer{buf: e}
+}
+
+// Reset resets the Buffer, ready for marshaling a new protocol buffer.
+func (p *Buffer) Reset() {
+	p.buf = p.buf[0:0] // for reading/writing
+	p.index = 0        // for reading
+}
+
+// SetBuf replaces the internal buffer with the slice,
+// ready for unmarshaling the contents of the slice.
+func (p *Buffer) SetBuf(s []byte) {
+	p.buf = s
+	p.index = 0
+}
+
+// Bytes returns the contents of the Buffer.
+func (p *Buffer) Bytes() []byte { return p.buf }
+
+/*
+ * Helper routines for simplifying the creation of optional fields of basic type.
+ */
+
+// Bool is a helper routine that allocates a new bool value
+// to store v and returns a pointer to it.
+func Bool(v bool) *bool {
+	return &v
+}
+
+// Int32 is a helper routine that allocates a new int32 value
+// to store v and returns a pointer to it.
+func Int32(v int32) *int32 {
+	return &v
+}
+
+// Int is a helper routine that allocates a new int32 value
+// to store v and returns a pointer to it, but unlike Int32
+// its argument value is an int.
+func Int(v int) *int32 {
+	p := new(int32)
+	*p = int32(v)
+	return p
+}
+
+// Int64 is a helper routine that allocates a new int64 value
+// to store v and returns a pointer to it.
+func Int64(v int64) *int64 {
+	return &v
+}
+
+// Float32 is a helper routine that allocates a new float32 value
+// to store v and returns a pointer to it.
+func Float32(v float32) *float32 {
+	return &v
+}
+
+// Float64 is a helper routine that allocates a new float64 value
+// to store v and returns a pointer to it.
+func Float64(v float64) *float64 {
+	return &v
+}
+
+// Uint32 is a helper routine that allocates a new uint32 value
+// to store v and returns a pointer to it.
+func Uint32(v uint32) *uint32 {
+	return &v
+}
+
+// Uint64 is a helper routine that allocates a new uint64 value
+// to store v and returns a pointer to it.
+func Uint64(v uint64) *uint64 {
+	return &v
+}
+
+// String is a helper routine that allocates a new string value
+// to store v and returns a pointer to it.
+func String(v string) *string {
+	return &v
+}
+
+// EnumName is a helper function to simplify printing protocol buffer enums
+// by name.  Given an enum map and a value, it returns a useful string.
+func EnumName(m map[int32]string, v int32) string {
+	s, ok := m[v]
+	if ok {
+		return s
+	}
+	return strconv.Itoa(int(v))
+}
+
+// UnmarshalJSONEnum is a helper function to simplify recovering enum int values
+// from their JSON-encoded representation. Given a map from the enum's symbolic
+// names to its int values, and a byte buffer containing the JSON-encoded
+// value, it returns an int32 that can be cast to the enum type by the caller.
+//
+// The function can deal with both JSON representations, numeric and symbolic.
+func UnmarshalJSONEnum(m map[string]int32, data []byte, enumName string) (int32, error) {
+	if data[0] == '"' {
+		// New style: enums are strings.
+		var repr string
+		if err := json.Unmarshal(data, &repr); err != nil {
+			return -1, err
+		}
+		val, ok := m[repr]
+		if !ok {
+			return 0, fmt.Errorf("unrecognized enum %s value %q", enumName, repr)
+		}
+		return val, nil
+	}
+	// Old style: enums are ints.
+	var val int32
+	if err := json.Unmarshal(data, &val); err != nil {
+		return 0, fmt.Errorf("cannot unmarshal %#q into enum %s", data, enumName)
+	}
+	return val, nil
+}
+
+// DebugPrint dumps the encoded data in b in a debugging format with a header
+// including the string s. Used in testing but made available for general debugging.
+func (p *Buffer) DebugPrint(s string, b []byte) {
+	var u uint64
+
+	obuf := p.buf
+	index := p.index
+	p.buf = b
+	p.index = 0
+	depth := 0
+
+	fmt.Printf("\n--- %s ---\n", s)
+
+out:
+	for {
+		for i := 0; i < depth; i++ {
+			fmt.Print("  ")
+		}
+
+		index := p.index
+		if index == len(p.buf) {
+			break
+		}
+
+		op, err := p.DecodeVarint()
+		if err != nil {
+			fmt.Printf("%3d: fetching op err %v\n", index, err)
+			break out
+		}
+		tag := op >> 3
+		wire := op & 7
+
+		switch wire {
+		default:
+			fmt.Printf("%3d: t=%3d unknown wire=%d\n",
+				index, tag, wire)
+			break out
+
+		case WireBytes:
+			var r []byte
+
+			r, err = p.DecodeRawBytes(false)
+			if err != nil {
+				break out
+			}
+			fmt.Printf("%3d: t=%3d bytes [%d]", index, tag, len(r))
+			if len(r) <= 6 {
+				for i := 0; i < len(r); i++ {
+					fmt.Printf(" %.2x", r[i])
+				}
+			} else {
+				for i := 0; i < 3; i++ {
+					fmt.Printf(" %.2x", r[i])
+				}
+				fmt.Printf(" ..")
+				for i := len(r) - 3; i < len(r); i++ {
+					fmt.Printf(" %.2x", r[i])
+				}
+			}
+			fmt.Printf("\n")
+
+		case WireFixed32:
+			u, err = p.DecodeFixed32()
+			if err != nil {
+				fmt.Printf("%3d: t=%3d fix32 err %v\n", index, tag, err)
+				break out
+			}
+			fmt.Printf("%3d: t=%3d fix32 %d\n", index, tag, u)
+
+		case WireFixed64:
+			u, err = p.DecodeFixed64()
+			if err != nil {
+				fmt.Printf("%3d: t=%3d fix64 err %v\n", index, tag, err)
+				break out
+			}
+			fmt.Printf("%3d: t=%3d fix64 %d\n", index, tag, u)
+
+		case WireVarint:
+			u, err = p.DecodeVarint()
+			if err != nil {
+				fmt.Printf("%3d: t=%3d varint err %v\n", index, tag, err)
+				break out
+			}
+			fmt.Printf("%3d: t=%3d varint %d\n", index, tag, u)
+
+		case WireStartGroup:
+			fmt.Printf("%3d: t=%3d start\n", index, tag)
+			depth++
+
+		case WireEndGroup:
+			depth--
+			fmt.Printf("%3d: t=%3d end\n", index, tag)
+		}
+	}
+
+	if depth != 0 {
+		fmt.Printf("%3d: start-end not balanced %d\n", p.index, depth)
+	}
+	fmt.Printf("\n")
+
+	p.buf = obuf
+	p.index = index
+}
+
+// SetDefaults sets unset protocol buffer fields to their default values.
+// It only modifies fields that are both unset and have defined defaults.
+// It recursively sets default values in any non-nil sub-messages.
+func SetDefaults(pb Message) {
+	setDefaults(reflect.ValueOf(pb), true, false)
+}
+
+// v is a pointer to a struct.
+func setDefaults(v reflect.Value, recur, zeros bool) {
+	v = v.Elem()
+
+	defaultMu.RLock()
+	dm, ok := defaults[v.Type()]
+	defaultMu.RUnlock()
+	if !ok {
+		dm = buildDefaultMessage(v.Type())
+		defaultMu.Lock()
+		defaults[v.Type()] = dm
+		defaultMu.Unlock()
+	}
+
+	for _, sf := range dm.scalars {
+		f := v.Field(sf.index)
+		if !f.IsNil() {
+			// field already set
+			continue
+		}
+		dv := sf.value
+		if dv == nil && !zeros {
+			// no explicit default, and don't want to set zeros
+			continue
+		}
+		fptr := f.Addr().Interface() // **T
+		// TODO: Consider batching the allocations we do here.
+		switch sf.kind {
+		case reflect.Bool:
+			b := new(bool)
+			if dv != nil {
+				*b = dv.(bool)
+			}
+			*(fptr.(**bool)) = b
+		case reflect.Float32:
+			f := new(float32)
+			if dv != nil {
+				*f = dv.(float32)
+			}
+			*(fptr.(**float32)) = f
+		case reflect.Float64:
+			f := new(float64)
+			if dv != nil {
+				*f = dv.(float64)
+			}
+			*(fptr.(**float64)) = f
+		case reflect.Int32:
+			// might be an enum
+			if ft := f.Type(); ft != int32PtrType {
+				// enum
+				f.Set(reflect.New(ft.Elem()))
+				if dv != nil {
+					f.Elem().SetInt(int64(dv.(int32)))
+				}
+			} else {
+				// int32 field
+				i := new(int32)
+				if dv != nil {
+					*i = dv.(int32)
+				}
+				*(fptr.(**int32)) = i
+			}
+		case reflect.Int64:
+			i := new(int64)
+			if dv != nil {
+				*i = dv.(int64)
+			}
+			*(fptr.(**int64)) = i
+		case reflect.String:
+			s := new(string)
+			if dv != nil {
+				*s = dv.(string)
+			}
+			*(fptr.(**string)) = s
+		case reflect.Uint8:
+			// exceptional case: []byte
+			var b []byte
+			if dv != nil {
+				db := dv.([]byte)
+				b = make([]byte, len(db))
+				copy(b, db)
+			} else {
+				b = []byte{}
+			}
+			*(fptr.(*[]byte)) = b
+		case reflect.Uint32:
+			u := new(uint32)
+			if dv != nil {
+				*u = dv.(uint32)
+			}
+			*(fptr.(**uint32)) = u
+		case reflect.Uint64:
+			u := new(uint64)
+			if dv != nil {
+				*u = dv.(uint64)
+			}
+			*(fptr.(**uint64)) = u
+		default:
+			log.Printf("proto: can't set default for field %v (sf.kind=%v)", f, sf.kind)
+		}
+	}
+
+	for _, ni := range dm.nested {
+		f := v.Field(ni)
+		// f is *T or []*T or map[T]*T
+		switch f.Kind() {
+		case reflect.Ptr:
+			if f.IsNil() {
+				continue
+			}
+			setDefaults(f, recur, zeros)
+
+		case reflect.Slice:
+			for i := 0; i < f.Len(); i++ {
+				e := f.Index(i)
+				if e.IsNil() {
+					continue
+				}
+				setDefaults(e, recur, zeros)
+			}
+
+		case reflect.Map:
+			for _, k := range f.MapKeys() {
+				e := f.MapIndex(k)
+				if e.IsNil() {
+					continue
+				}
+				setDefaults(e, recur, zeros)
+			}
+		}
+	}
+}
+
+var (
+	// defaults maps a protocol buffer struct type to a slice of the fields,
+	// with its scalar fields set to their proto-declared non-zero default values.
+	defaultMu sync.RWMutex
+	defaults  = make(map[reflect.Type]defaultMessage)
+
+	int32PtrType = reflect.TypeOf((*int32)(nil))
+)
+
+// defaultMessage represents information about the default values of a message.
+type defaultMessage struct {
+	scalars []scalarField
+	nested  []int // struct field index of nested messages
+}
+
+type scalarField struct {
+	index int          // struct field index
+	kind  reflect.Kind // element type (the T in *T or []T)
+	value interface{}  // the proto-declared default value, or nil
+}
+
+// t is a struct type.
+func buildDefaultMessage(t reflect.Type) (dm defaultMessage) {
+	sprop := GetProperties(t)
+	for _, prop := range sprop.Prop {
+		fi, ok := sprop.decoderTags.get(prop.Tag)
+		if !ok {
+			// XXX_unrecognized
+			continue
+		}
+		ft := t.Field(fi).Type
+
+		sf, nested, err := fieldDefault(ft, prop)
+		switch {
+		case err != nil:
+			log.Print(err)
+		case nested:
+			dm.nested = append(dm.nested, fi)
+		case sf != nil:
+			sf.index = fi
+			dm.scalars = append(dm.scalars, *sf)
+		}
+	}
+
+	return dm
+}
+
+// fieldDefault returns the scalarField for field type ft.
+// sf will be nil if the field can not have a default.
+// nestedMessage will be true if this is a nested message.
+// Note that sf.index is not set on return.
+func fieldDefault(ft reflect.Type, prop *Properties) (sf *scalarField, nestedMessage bool, err error) {
+	var canHaveDefault bool
+	switch ft.Kind() {
+	case reflect.Ptr:
+		if ft.Elem().Kind() == reflect.Struct {
+			nestedMessage = true
+		} else {
+			canHaveDefault = true // proto2 scalar field
+		}
+
+	case reflect.Slice:
+		switch ft.Elem().Kind() {
+		case reflect.Ptr:
+			nestedMessage = true // repeated message
+		case reflect.Uint8:
+			canHaveDefault = true // bytes field
+		}
+
+	case reflect.Map:
+		if ft.Elem().Kind() == reflect.Ptr {
+			nestedMessage = true // map with message values
+		}
+	}
+
+	if !canHaveDefault {
+		if nestedMessage {
+			return nil, true, nil
+		}
+		return nil, false, nil
+	}
+
+	// We now know that ft is a pointer or slice.
+	sf = &scalarField{kind: ft.Elem().Kind()}
+
+	// scalar fields without defaults
+	if !prop.HasDefault {
+		return sf, false, nil
+	}
+
+	// a scalar field: either *T or []byte
+	switch ft.Elem().Kind() {
+	case reflect.Bool:
+		x, err := strconv.ParseBool(prop.Default)
+		if err != nil {
+			return nil, false, fmt.Errorf("proto: bad default bool %q: %v", prop.Default, err)
+		}
+		sf.value = x
+	case reflect.Float32:
+		x, err := strconv.ParseFloat(prop.Default, 32)
+		if err != nil {
+			return nil, false, fmt.Errorf("proto: bad default float32 %q: %v", prop.Default, err)
+		}
+		sf.value = float32(x)
+	case reflect.Float64:
+		x, err := strconv.ParseFloat(prop.Default, 64)
+		if err != nil {
+			return nil, false, fmt.Errorf("proto: bad default float64 %q: %v", prop.Default, err)
+		}
+		sf.value = x
+	case reflect.Int32:
+		x, err := strconv.ParseInt(prop.Default, 10, 32)
+		if err != nil {
+			return nil, false, fmt.Errorf("proto: bad default int32 %q: %v", prop.Default, err)
+		}
+		sf.value = int32(x)
+	case reflect.Int64:
+		x, err := strconv.ParseInt(prop.Default, 10, 64)
+		if err != nil {
+			return nil, false, fmt.Errorf("proto: bad default int64 %q: %v", prop.Default, err)
+		}
+		sf.value = x
+	case reflect.String:
+		sf.value = prop.Default
+	case reflect.Uint8:
+		// []byte (not *uint8)
+		sf.value = []byte(prop.Default)
+	case reflect.Uint32:
+		x, err := strconv.ParseUint(prop.Default, 10, 32)
+		if err != nil {
+			return nil, false, fmt.Errorf("proto: bad default uint32 %q: %v", prop.Default, err)
+		}
+		sf.value = uint32(x)
+	case reflect.Uint64:
+		x, err := strconv.ParseUint(prop.Default, 10, 64)
+		if err != nil {
+			return nil, false, fmt.Errorf("proto: bad default uint64 %q: %v", prop.Default, err)
+		}
+		sf.value = x
+	default:
+		return nil, false, fmt.Errorf("proto: unhandled def kind %v", ft.Elem().Kind())
+	}
+
+	return sf, false, nil
+}
+
+// Map fields may have key types of non-float scalars, strings and enums.
+// The easiest way to sort them in some deterministic order is to use fmt.
+// If this turns out to be inefficient we can always consider other options,
+// such as doing a Schwartzian transform.
+
+func mapKeys(vs []reflect.Value) sort.Interface {
+	s := mapKeySorter{
+		vs: vs,
+		// default Less function: textual comparison
+		less: func(a, b reflect.Value) bool {
+			return fmt.Sprint(a.Interface()) < fmt.Sprint(b.Interface())
+		},
+	}
+
+	// Type specialization per https://developers.google.com/protocol-buffers/docs/proto#maps;
+	// numeric keys are sorted numerically.
+	if len(vs) == 0 {
+		return s
+	}
+	switch vs[0].Kind() {
+	case reflect.Int32, reflect.Int64:
+		s.less = func(a, b reflect.Value) bool { return a.Int() < b.Int() }
+	case reflect.Uint32, reflect.Uint64:
+		s.less = func(a, b reflect.Value) bool { return a.Uint() < b.Uint() }
+	}
+
+	return s
+}
+
+type mapKeySorter struct {
+	vs   []reflect.Value
+	less func(a, b reflect.Value) bool
+}
+
+func (s mapKeySorter) Len() int      { return len(s.vs) }
+func (s mapKeySorter) Swap(i, j int) { s.vs[i], s.vs[j] = s.vs[j], s.vs[i] }
+func (s mapKeySorter) Less(i, j int) bool {
+	return s.less(s.vs[i], s.vs[j])
+}
+
+// isProto3Zero reports whether v is a zero proto3 value.
+func isProto3Zero(v reflect.Value) bool {
+	switch v.Kind() {
+	case reflect.Bool:
+		return !v.Bool()
+	case reflect.Int32, reflect.Int64:
+		return v.Int() == 0
+	case reflect.Uint32, reflect.Uint64:
+		return v.Uint() == 0
+	case reflect.Float32, reflect.Float64:
+		return v.Float() == 0
+	case reflect.String:
+		return v.String() == ""
+	}
+	return false
+}
+
+// ProtoPackageIsVersion2 is referenced from generated protocol buffer files
+// to assert that that code is compatible with this version of the proto package.
+const ProtoPackageIsVersion2 = true
+
+// ProtoPackageIsVersion1 is referenced from generated protocol buffer files
+// to assert that that code is compatible with this version of the proto package.
+const ProtoPackageIsVersion1 = true

go/vendor/github.com/golang/protobuf/proto/message_set.go

+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2010 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
+
+/*
+ * Support for message sets.
+ */
+
+import (
+	"bytes"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"reflect"
+	"sort"
+)
+
+// errNoMessageTypeID occurs when a protocol buffer does not have a message type ID.
+// A message type ID is required for storing a protocol buffer in a message set.
+var errNoMessageTypeID = errors.New("proto does not have a message type ID")
+
+// The first two types (_MessageSet_Item and messageSet)
+// model what the protocol compiler produces for the following protocol message:
+//   message MessageSet {
+//     repeated group Item = 1 {
+//       required int32 type_id = 2;
+//       required string message = 3;
+//     };
+//   }
+// That is the MessageSet wire format. We can't use a proto to generate these
+// because that would introduce a circular dependency between it and this package.
+
+type _MessageSet_Item struct {
+	TypeId  *int32 `protobuf:"varint,2,req,name=type_id"`
+	Message []byte `protobuf:"bytes,3,req,name=message"`
+}
+
+type messageSet struct {
+	Item             []*_MessageSet_Item `protobuf:"group,1,rep"`
+	XXX_unrecognized []byte
+	// TODO: caching?
+}
+
+// Make sure messageSet is a Message.
+var _ Message = (*messageSet)(nil)
+
+// messageTypeIder is an interface satisfied by a protocol buffer type
+// that may be stored in a MessageSet.
+type messageTypeIder interface {
+	MessageTypeId() int32
+}
+
+func (ms *messageSet) find(pb Message) *_MessageSet_Item {
+	mti, ok := pb.(messageTypeIder)
+	if !ok {
+		return nil
+	}
+	id := mti.MessageTypeId()
+	for _, item := range ms.Item {
+		if *item.TypeId == id {
+			return item
+		}
+	}
+	return nil
+}
+
+func (ms *messageSet) Has(pb Message) bool {
+	if ms.find(pb) != nil {
+		return true
+	}
+	return false
+}
+
+func (ms *messageSet) Unmarshal(pb Message) error {
+	if item := ms.find(pb); item != nil {
+		return Unmarshal(item.Message, pb)
+	}
+	if _, ok := pb.(messageTypeIder); !ok {
+		return errNoMessageTypeID
+	}
+	return nil // TODO: return error instead?
+}
+
+func (ms *messageSet) Marshal(pb Message) error {
+	msg, err := Marshal(pb)
+	if err != nil {
+		return err
+	}
+	if item := ms.find(pb); item != nil {
+		// reuse existing item
+		item.Message = msg
+		return nil
+	}
+
+	mti, ok := pb.(messageTypeIder)
+	if !ok {
+		return errNoMessageTypeID
+	}
+
+	mtid := mti.MessageTypeId()
+	ms.Item = append(ms.Item, &_MessageSet_Item{
+		TypeId:  &mtid,
+		Message: msg,
+	})
+	return nil
+}
+
+func (ms *messageSet) Reset()         { *ms = messageSet{} }
+func (ms *messageSet) String() string { return CompactTextString(ms) }
+func (*messageSet) ProtoMessage()     {}
+
+// Support for the message_set_wire_format message option.
+
+func skipVarint(buf []byte) []byte {
+	i := 0
+	for ; buf[i]&0x80 != 0; i++ {
+	}
+	return buf[i+1:]
+}
+
+// MarshalMessageSet encodes the extension map represented by m in the message set wire format.
+// It is called by generated Marshal methods on protocol buffer messages with the message_set_wire_format option.
+func MarshalMessageSet(exts interface{}) ([]byte, error) {
+	var m map[int32]Extension
+	switch exts := exts.(type) {
+	case *XXX_InternalExtensions:
+		if err := encodeExtensions(exts); err != nil {
+			return nil, err
+		}
+		m, _ = exts.extensionsRead()
+	case map[int32]Extension:
+		if err := encodeExtensionsMap(exts); err != nil {
+			return nil, err
+		}
+		m = exts
+	default:
+		return nil, errors.New("proto: not an extension map")
+	}
+
+	// Sort extension IDs to provide a deterministic encoding.
+	// See also enc_map in encode.go.
+	ids := make([]int, 0, len(m))
+	for id := range m {
+		ids = append(ids, int(id))
+	}
+	sort.Ints(ids)
+
+	ms := &messageSet{Item: make([]*_MessageSet_Item, 0, len(m))}
+	for _, id := range ids {
+		e := m[int32(id)]
+		// Remove the wire type and field number varint, as well as the length varint.
+		msg := skipVarint(skipVarint(e.enc))
+
+		ms.Item = append(ms.Item, &_MessageSet_Item{
+			TypeId:  Int32(int32(id)),
+			Message: msg,
+		})
+	}
+	return Marshal(ms)
+}
+
+// UnmarshalMessageSet decodes the extension map encoded in buf in the message set wire format.
+// It is called by generated Unmarshal methods on protocol buffer messages with the message_set_wire_format option.
+func UnmarshalMessageSet(buf []byte, exts interface{}) error {
+	var m map[int32]Extension
+	switch exts := exts.(type) {
+	case *XXX_InternalExtensions:
+		m = exts.extensionsWrite()
+	case map[int32]Extension:
+		m = exts
+	default:
+		return errors.New("proto: not an extension map")
+	}
+
+	ms := new(messageSet)
+	if err := Unmarshal(buf, ms); err != nil {
+		return err
+	}
+	for _, item := range ms.Item {
+		id := *item.TypeId
+		msg := item.Message
+
+		// Restore wire type and field number varint, plus length varint.
+		// Be careful to preserve duplicate items.
+		b := EncodeVarint(uint64(id)<<3 | WireBytes)
+		if ext, ok := m[id]; ok {
+			// Existing data; rip off the tag and length varint
+			// so we join the new data correctly.
+			// We can assume that ext.enc is set because we are unmarshaling.
+			o := ext.enc[len(b):]   // skip wire type and field number
+			_, n := DecodeVarint(o) // calculate length of length varint
+			o = o[n:]               // skip length varint
+			msg = append(o, msg...) // join old data and new data
+		}
+		b = append(b, EncodeVarint(uint64(len(msg)))...)
+		b = append(b, msg...)
+
+		m[id] = Extension{enc: b}
+	}
+	return nil
+}
+
+// MarshalMessageSetJSON encodes the extension map represented by m in JSON format.
+// It is called by generated MarshalJSON methods on protocol buffer messages with the message_set_wire_format option.
+func MarshalMessageSetJSON(exts interface{}) ([]byte, error) {
+	var m map[int32]Extension
+	switch exts := exts.(type) {
+	case *XXX_InternalExtensions:
+		m, _ = exts.extensionsRead()
+	case map[int32]Extension:
+		m = exts
+	default:
+		return nil, errors.New("proto: not an extension map")
+	}
+	var b bytes.Buffer
+	b.WriteByte('{')
+
+	// Process the map in key order for deterministic output.
+	ids := make([]int32, 0, len(m))
+	for id := range m {
+		ids = append(ids, id)
+	}
+	sort.Sort(int32Slice(ids)) // int32Slice defined in text.go
+
+	for i, id := range ids {
+		ext := m[id]
+		if i > 0 {
+			b.WriteByte(',')
+		}
+
+		msd, ok := messageSetMap[id]
+		if !ok {
+			// Unknown type; we can't render it, so skip it.
+			continue
+		}
+		fmt.Fprintf(&b, `"[%s]":`, msd.name)
+
+		x := ext.value
+		if x == nil {
+			x = reflect.New(msd.t.Elem()).Interface()
+			if err := Unmarshal(ext.enc, x.(Message)); err != nil {
+				return nil, err
+			}
+		}
+		d, err := json.Marshal(x)
+		if err != nil {
+			return nil, err
+		}
+		b.Write(d)
+	}
+	b.WriteByte('}')
+	return b.Bytes(), nil
+}
+
+// UnmarshalMessageSetJSON decodes the extension map encoded in buf in JSON format.
+// It is called by generated UnmarshalJSON methods on protocol buffer messages with the message_set_wire_format option.
+func UnmarshalMessageSetJSON(buf []byte, exts interface{}) error {
+	// Common-case fast path.
+	if len(buf) == 0 || bytes.Equal(buf, []byte("{}")) {
+		return nil
+	}
+
+	// This is fairly tricky, and it's not clear that it is needed.
+	return errors.New("TODO: UnmarshalMessageSetJSON not yet implemented")
+}
+
+// A global registry of types that can be used in a MessageSet.
+
+var messageSetMap = make(map[int32]messageSetDesc)
+
+type messageSetDesc struct {
+	t    reflect.Type // pointer to struct
+	name string
+}
+
+// RegisterMessageSetType is called from the generated code.
+func RegisterMessageSetType(m Message, fieldNum int32, name string) {
+	messageSetMap[fieldNum] = messageSetDesc{
+		t:    reflect.TypeOf(m),
+		name: name,
+	}
+}

go/vendor/github.com/golang/protobuf/proto/pointer_reflect.go

+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2012 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.
+
+// +build appengine js
+
+// This file contains an implementation of proto field accesses using package reflect.
+// It is slower than the code in pointer_unsafe.go but it avoids package unsafe and can
+// be used on App Engine.
+
+package proto
+
+import (
+	"math"
+	"reflect"
+)
+
+// A structPointer is a pointer to a struct.
+type structPointer struct {
+	v reflect.Value
+}
+
+// toStructPointer returns a structPointer equivalent to the given reflect value.
+// The reflect value must itself be a pointer to a struct.
+func toStructPointer(v reflect.Value) structPointer {
+	return structPointer{v}
+}
+
+// IsNil reports whether p is nil.
+func structPointer_IsNil(p structPointer) bool {
+	return p.v.IsNil()
+}
+
+// Interface returns the struct pointer as an interface value.
+func structPointer_Interface(p structPointer, _ reflect.Type) interface{} {
+	return p.v.Interface()
+}
+
+// A field identifies a field in a struct, accessible from a structPointer.
+// In this implementation, a field is identified by the sequence of field indices
+// passed to reflect's FieldByIndex.
+type field []int
+
+// toField returns a field equivalent to the given reflect field.
+func toField(f *reflect.StructField) field {
+	return f.Index
+}
+
+// invalidField is an invalid field identifier.
+var invalidField = field(nil)
+
+// IsValid reports whether the field identifier is valid.
+func (f field) IsValid() bool { return f != nil }
+
+// field returns the given field in the struct as a reflect value.
+func structPointer_field(p structPointer, f field) reflect.Value {
+	// Special case: an extension map entry with a value of type T
+	// passes a *T to the struct-handling code with a zero field,
+	// expecting that it will be treated as equivalent to *struct{ X T },
+	// which has the same memory layout. We have to handle that case
+	// specially, because reflect will panic if we call FieldByIndex on a
+	// non-struct.
+	if f == nil {
+		return p.v.Elem()
+	}
+
+	return p.v.Elem().FieldByIndex(f)
+}
+
+// ifield returns the given field in the struct as an interface value.
+func structPointer_ifield(p structPointer, f field) interface{} {
+	return structPointer_field(p, f).Addr().Interface()
+}
+
+// Bytes returns the address of a []byte field in the struct.
+func structPointer_Bytes(p structPointer, f field) *[]byte {
+	return structPointer_ifield(p, f).(*[]byte)
+}
+
+// BytesSlice returns the address of a [][]byte field in the struct.
+func structPointer_BytesSlice(p structPointer, f field) *[][]byte {
+	return structPointer_ifield(p, f).(*[][]byte)
+}
+
+// Bool returns the address of a *bool field in the struct.
+func structPointer_Bool(p structPointer, f field) **bool {
+	return structPointer_ifield(p, f).(**bool)
+}
+
+// BoolVal returns the address of a bool field in the struct.
+func structPointer_BoolVal(p structPointer, f field) *bool {
+	return structPointer_ifield(p, f).(*bool)
+}
+
+// BoolSlice returns the address of a []bool field in the struct.
+func structPointer_BoolSlice(p structPointer, f field) *[]bool {
+	return structPointer_ifield(p, f).(*[]bool)
+}
+
+// String returns the address of a *string field in the struct.
+func structPointer_String(p structPointer, f field) **string {
+	return structPointer_ifield(p, f).(**string)
+}
+
+// StringVal returns the address of a string field in the struct.
+func structPointer_StringVal(p structPointer, f field) *string {
+	return structPointer_ifield(p, f).(*string)
+}
+
+// StringSlice returns the address of a []string field in the struct.
+func structPointer_StringSlice(p structPointer, f field) *[]string {
+	return structPointer_ifield(p, f).(*[]string)
+}
+
+// Extensions returns the address of an extension map field in the struct.
+func structPointer_Extensions(p structPointer, f field) *XXX_InternalExtensions {
+	return structPointer_ifield(p, f).(*XXX_InternalExtensions)
+}
+
+// ExtMap returns the address of an extension map field in the struct.
+func structPointer_ExtMap(p structPointer, f field) *map[int32]Extension {
+	return structPointer_ifield(p, f).(*map[int32]Extension)
+}
+
+// NewAt returns the reflect.Value for a pointer to a field in the struct.
+func structPointer_NewAt(p structPointer, f field, typ reflect.Type) reflect.Value {
+	return structPointer_field(p, f).Addr()
+}
+
+// SetStructPointer writes a *struct field in the struct.
+func structPointer_SetStructPointer(p structPointer, f field, q structPointer) {
+	structPointer_field(p, f).Set(q.v)
+}
+
+// GetStructPointer reads a *struct field in the struct.
+func structPointer_GetStructPointer(p structPointer, f field) structPointer {
+	return structPointer{structPointer_field(p, f)}
+}
+
+// StructPointerSlice the address of a []*struct field in the struct.
+func structPointer_StructPointerSlice(p structPointer, f field) structPointerSlice {
+	return structPointerSlice{structPointer_field(p, f)}
+}
+
+// A structPointerSlice represents the address of a slice of pointers to structs
+// (themselves messages or groups). That is, v.Type() is *[]*struct{...}.
+type structPointerSlice struct {
+	v reflect.Value
+}
+
+func (p structPointerSlice) Len() int                  { return p.v.Len() }
+func (p structPointerSlice) Index(i int) structPointer { return structPointer{p.v.Index(i)} }
+func (p structPointerSlice) Append(q structPointer) {
+	p.v.Set(reflect.Append(p.v, q.v))
+}
+
+var (
+	int32Type   = reflect.TypeOf(int32(0))
+	uint32Type  = reflect.TypeOf(uint32(0))
+	float32Type = reflect.TypeOf(float32(0))
+	int64Type   = reflect.TypeOf(int64(0))
+	uint64Type  = reflect.TypeOf(uint64(0))
+	float64Type = reflect.TypeOf(float64(0))
+)
+
+// A word32 represents a field of type *int32, *uint32, *float32, or *enum.
+// That is, v.Type() is *int32, *uint32, *float32, or *enum and v is assignable.
+type word32 struct {
+	v reflect.Value
+}
+
+// IsNil reports whether p is nil.
+func word32_IsNil(p word32) bool {
+	return p.v.IsNil()
+}
+
+// Set sets p to point at a newly allocated word with bits set to x.
+func word32_Set(p word32, o *Buffer, x uint32) {
+	t := p.v.Type().Elem()
+	switch t {
+	case int32Type:
+		if len(o.int32s) == 0 {
+			o.int32s = make([]int32, uint32PoolSize)
+		}
+		o.int32s[0] = int32(x)
+		p.v.Set(reflect.ValueOf(&o.int32s[0]))
+		o.int32s = o.int32s[1:]
+		return
+	case uint32Type:
+		if len(o.uint32s) == 0 {
+			o.uint32s = make([]uint32, uint32PoolSize)
+		}
+		o.uint32s[0] = x
+		p.v.Set(reflect.ValueOf(&o.uint32s[0]))
+		o.uint32s = o.uint32s[1:]
+		return
+	case float32Type:
+		if len(o.float32s) == 0 {
+			o.float32s = make([]float32, uint32PoolSize)
+		}
+		o.float32s[0] = math.Float32frombits(x)
+		p.v.Set(reflect.ValueOf(&o.float32s[0]))
+		o.float32s = o.float32s[1:]
+		return
+	}
+
+	// must be enum
+	p.v.Set(reflect.New(t))
+	p.v.Elem().SetInt(int64(int32(x)))
+}
+
+// Get gets the bits pointed at by p, as a uint32.
+func word32_Get(p word32) uint32 {
+	elem := p.v.Elem()
+	switch elem.Kind() {
+	case reflect.Int32:
+		return uint32(elem.Int())
+	case reflect.Uint32:
+		return uint32(elem.Uint())
+	case reflect.Float32:
+		return math.Float32bits(float32(elem.Float()))
+	}
+	panic("unreachable")
+}
+
+// Word32 returns a reference to a *int32, *uint32, *float32, or *enum field in the struct.
+func structPointer_Word32(p structPointer, f field) word32 {
+	return word32{structPointer_field(p, f)}
+}
+
+// A word32Val represents a field of type int32, uint32, float32, or enum.
+// That is, v.Type() is int32, uint32, float32, or enum and v is assignable.
+type word32Val struct {
+	v reflect.Value
+}
+
+// Set sets *p to x.
+func word32Val_Set(p word32Val, x uint32) {
+	switch p.v.Type() {
+	case int32Type:
+		p.v.SetInt(int64(x))
+		return
+	case uint32Type:
+		p.v.SetUint(uint64(x))
+		return
+	case float32Type:
+		p.v.SetFloat(float64(math.Float32frombits(x)))
+		return
+	}
+
+	// must be enum
+	p.v.SetInt(int64(int32(x)))
+}
+
+// Get gets the bits pointed at by p, as a uint32.
+func word32Val_Get(p word32Val) uint32 {
+	elem := p.v
+	switch elem.Kind() {
+	case reflect.Int32:
+		return uint32(elem.Int())
+	case reflect.Uint32:
+		return uint32(elem.Uint())
+	case reflect.Float32:
+		return math.Float32bits(float32(elem.Float()))
+	}
+	panic("unreachable")
+}
+
+// Word32Val returns a reference to a int32, uint32, float32, or enum field in the struct.
+func structPointer_Word32Val(p structPointer, f field) word32Val {
+	return word32Val{structPointer_field(p, f)}
+}
+
+// A word32Slice is a slice of 32-bit values.
+// That is, v.Type() is []int32, []uint32, []float32, or []enum.
+type word32Slice struct {
+	v reflect.Value
+}
+
+func (p word32Slice) Append(x uint32) {
+	n, m := p.v.Len(), p.v.Cap()
+	if n < m {
+		p.v.SetLen(n + 1)
+	} else {
+		t := p.v.Type().Elem()
+		p.v.Set(reflect.Append(p.v, reflect.Zero(t)))
+	}
+	elem := p.v.Index(n)
+	switch elem.Kind() {
+	case reflect.Int32:
+		elem.SetInt(int64(int32(x)))
+	case reflect.Uint32:
+		elem.SetUint(uint64(x))
+	case reflect.Float32:
+		elem.SetFloat(float64(math.Float32frombits(x)))
+	}
+}
+
+func (p word32Slice) Len() int {
+	return p.v.Len()
+}
+
+func (p word32Slice) Index(i int) uint32 {
+	elem := p.v.Index(i)
+	switch elem.Kind() {
+	case reflect.Int32:
+		return uint32(elem.Int())
+	case reflect.Uint32:
+		return uint32(elem.Uint())
+	case reflect.Float32:
+		return math.Float32bits(float32(elem.Float()))
+	}
+	panic("unreachable")
+}
+
+// Word32Slice returns a reference to a []int32, []uint32, []float32, or []enum field in the struct.
+func structPointer_Word32Slice(p structPointer, f field) word32Slice {
+	return word32Slice{structPointer_field(p, f)}
+}
+
+// word64 is like word32 but for 64-bit values.
+type word64 struct {
+	v reflect.Value
+}
+
+func word64_Set(p word64, o *Buffer, x uint64) {
+	t := p.v.Type().Elem()
+	switch t {
+	case int64Type:
+		if len(o.int64s) == 0 {
+			o.int64s = make([]int64, uint64PoolSize)
+		}
+		o.int64s[0] = int64(x)
+		p.v.Set(reflect.ValueOf(&o.int64s[0]))
+		o.int64s = o.int64s[1:]
+		return
+	case uint64Type:
+		if len(o.uint64s) == 0 {
+			o.uint64s = make([]uint64, uint64PoolSize)
+		}
+		o.uint64s[0] = x
+		p.v.Set(reflect.ValueOf(&o.uint64s[0]))
+		o.uint64s = o.uint64s[1:]
+		return
+	case float64Type:
+		if len(o.float64s) == 0 {
+			o.float64s = make([]float64, uint64PoolSize)
+		}
+		o.float64s[0] = math.Float64frombits(x)
+		p.v.Set(reflect.ValueOf(&o.float64s[0]))
+		o.float64s = o.float64s[1:]
+		return
+	}
+	panic("unreachable")
+}
+
+func word64_IsNil(p word64) bool {
+	return p.v.IsNil()
+}
+
+func word64_Get(p word64) uint64 {
+	elem := p.v.Elem()
+	switch elem.Kind() {
+	case reflect.Int64:
+		return uint64(elem.Int())
+	case reflect.Uint64:
+		return elem.Uint()
+	case reflect.Float64:
+		return math.Float64bits(elem.Float())
+	}
+	panic("unreachable")
+}
+
+func structPointer_Word64(p structPointer, f field) word64 {
+	return word64{structPointer_field(p, f)}
+}
+
+// word64Val is like word32Val but for 64-bit values.
+type word64Val struct {
+	v reflect.Value
+}
+
+func word64Val_Set(p word64Val, o *Buffer, x uint64) {
+	switch p.v.Type() {
+	case int64Type:
+		p.v.SetInt(int64(x))
+		return
+	case uint64Type:
+		p.v.SetUint(x)
+		return
+	case float64Type:
+		p.v.SetFloat(math.Float64frombits(x))
+		return
+	}
+	panic("unreachable")
+}
+
+func word64Val_Get(p word64Val) uint64 {
+	elem := p.v
+	switch elem.Kind() {
+	case reflect.Int64:
+		return uint64(elem.Int())
+	case reflect.Uint64:
+		return elem.Uint()
+	case reflect.Float64:
+		return math.Float64bits(elem.Float())
+	}
+	panic("unreachable")
+}
+
+func structPointer_Word64Val(p structPointer, f field) word64Val {
+	return word64Val{structPointer_field(p, f)}
+}
+
+type word64Slice struct {
+	v reflect.Value
+}
+
+func (p word64Slice) Append(x uint64) {
+	n, m := p.v.Len(), p.v.Cap()
+	if n < m {
+		p.v.SetLen(n + 1)
+	} else {
+		t := p.v.Type().Elem()
+		p.v.Set(reflect.Append(p.v, reflect.Zero(t)))
+	}
+	elem := p.v.Index(n)
+	switch elem.Kind() {
+	case reflect.Int64:
+		elem.SetInt(int64(int64(x)))
+	case reflect.Uint64:
+		elem.SetUint(uint64(x))
+	case reflect.Float64:
+		elem.SetFloat(float64(math.Float64frombits(x)))
+	}
+}
+
+func (p word64Slice) Len() int {
+	return p.v.Len()
+}
+
+func (p word64Slice) Index(i int) uint64 {
+	elem := p.v.Index(i)
+	switch elem.Kind() {
+	case reflect.Int64:
+		return uint64(elem.Int())
+	case reflect.Uint64:
+		return uint64(elem.Uint())
+	case reflect.Float64:
+		return math.Float64bits(float64(elem.Float()))
+	}
+	panic("unreachable")
+}
+
+func structPointer_Word64Slice(p structPointer, f field) word64Slice {
+	return word64Slice{structPointer_field(p, f)}
+}

go/vendor/github.com/golang/protobuf/proto/pointer_unsafe.go

+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2012 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.
+
+// +build !appengine,!js
+
+// This file contains the implementation of the proto field accesses using package unsafe.
+
+package proto
+
+import (
+	"reflect"
+	"unsafe"
+)
+
+// NOTE: These type_Foo functions would more idiomatically be methods,
+// but Go does not allow methods on pointer types, and we must preserve
+// some pointer type for the garbage collector. We use these
+// funcs with clunky names as our poor approximation to methods.
+//
+// An alternative would be
+//	type structPointer struct { p unsafe.Pointer }
+// but that does not registerize as well.
+
+// A structPointer is a pointer to a struct.
+type structPointer unsafe.Pointer
+
+// toStructPointer returns a structPointer equivalent to the given reflect value.
+func toStructPointer(v reflect.Value) structPointer {
+	return structPointer(unsafe.Pointer(v.Pointer()))
+}
+
+// IsNil reports whether p is nil.
+func structPointer_IsNil(p structPointer) bool {
+	return p == nil
+}
+
+// Interface returns the struct pointer, assumed to have element type t,
+// as an interface value.
+func structPointer_Interface(p structPointer, t reflect.Type) interface{} {
+	return reflect.NewAt(t, unsafe.Pointer(p)).Interface()
+}
+
+// A field identifies a field in a struct, accessible from a structPointer.
+// In this implementation, a field is identified by its byte offset from the start of the struct.
+type field uintptr
+
+// toField returns a field equivalent to the given reflect field.
+func toField(f *reflect.StructField) field {
+	return field(f.Offset)
+}
+
+// invalidField is an invalid field identifier.
+const invalidField = ^field(0)
+
+// IsValid reports whether the field identifier is valid.
+func (f field) IsValid() bool {
+	return f != ^field(0)
+}
+
+// Bytes returns the address of a []byte field in the struct.
+func structPointer_Bytes(p structPointer, f field) *[]byte {
+	return (*[]byte)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+}
+
+// BytesSlice returns the address of a [][]byte field in the struct.
+func structPointer_BytesSlice(p structPointer, f field) *[][]byte {
+	return (*[][]byte)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+}
+
+// Bool returns the address of a *bool field in the struct.
+func structPointer_Bool(p structPointer, f field) **bool {
+	return (**bool)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+}
+
+// BoolVal returns the address of a bool field in the struct.
+func structPointer_BoolVal(p structPointer, f field) *bool {
+	return (*bool)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+}
+
+// BoolSlice returns the address of a []bool field in the struct.
+func structPointer_BoolSlice(p structPointer, f field) *[]bool {
+	return (*[]bool)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+}
+
+// String returns the address of a *string field in the struct.
+func structPointer_String(p structPointer, f field) **string {
+	return (**string)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+}
+
+// StringVal returns the address of a string field in the struct.
+func structPointer_StringVal(p structPointer, f field) *string {
+	return (*string)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+}
+
+// StringSlice returns the address of a []string field in the struct.
+func structPointer_StringSlice(p structPointer, f field) *[]string {
+	return (*[]string)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+}
+
+// ExtMap returns the address of an extension map field in the struct.
+func structPointer_Extensions(p structPointer, f field) *XXX_InternalExtensions {
+	return (*XXX_InternalExtensions)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+}
+
+func structPointer_ExtMap(p structPointer, f field) *map[int32]Extension {
+	return (*map[int32]Extension)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+}
+
+// NewAt returns the reflect.Value for a pointer to a field in the struct.
+func structPointer_NewAt(p structPointer, f field, typ reflect.Type) reflect.Value {
+	return reflect.NewAt(typ, unsafe.Pointer(uintptr(p)+uintptr(f)))
+}
+
+// SetStructPointer writes a *struct field in the struct.
+func structPointer_SetStructPointer(p structPointer, f field, q structPointer) {
+	*(*structPointer)(unsafe.Pointer(uintptr(p) + uintptr(f))) = q
+}
+
+// GetStructPointer reads a *struct field in the struct.
+func structPointer_GetStructPointer(p structPointer, f field) structPointer {
+	return *(*structPointer)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+}
+
+// StructPointerSlice the address of a []*struct field in the struct.
+func structPointer_StructPointerSlice(p structPointer, f field) *structPointerSlice {
+	return (*structPointerSlice)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+}
+
+// A structPointerSlice represents a slice of pointers to structs (themselves submessages or groups).
+type structPointerSlice []structPointer
+
+func (v *structPointerSlice) Len() int                  { return len(*v) }
+func (v *structPointerSlice) Index(i int) structPointer { return (*v)[i] }
+func (v *structPointerSlice) Append(p structPointer)    { *v = append(*v, p) }
+
+// A word32 is the address of a "pointer to 32-bit value" field.
+type word32 **uint32
+
+// IsNil reports whether *v is nil.
+func word32_IsNil(p word32) bool {
+	return *p == nil
+}
+
+// Set sets *v to point at a newly allocated word set to x.
+func word32_Set(p word32, o *Buffer, x uint32) {
+	if len(o.uint32s) == 0 {
+		o.uint32s = make([]uint32, uint32PoolSize)
+	}
+	o.uint32s[0] = x
+	*p = &o.uint32s[0]
+	o.uint32s = o.uint32s[1:]
+}
+
+// Get gets the value pointed at by *v.
+func word32_Get(p word32) uint32 {
+	return **p
+}
+
+// Word32 returns the address of a *int32, *uint32, *float32, or *enum field in the struct.
+func structPointer_Word32(p structPointer, f field) word32 {
+	return word32((**uint32)(unsafe.Pointer(uintptr(p) + uintptr(f))))
+}
+
+// A word32Val is the address of a 32-bit value field.
+type word32Val *uint32
+
+// Set sets *p to x.
+func word32Val_Set(p word32Val, x uint32) {
+	*p = x
+}
+
+// Get gets the value pointed at by p.
+func word32Val_Get(p word32Val) uint32 {
+	return *p
+}
+
+// Word32Val returns the address of a *int32, *uint32, *float32, or *enum field in the struct.
+func structPointer_Word32Val(p structPointer, f field) word32Val {
+	return word32Val((*uint32)(unsafe.Pointer(uintptr(p) + uintptr(f))))
+}
+
+// A word32Slice is a slice of 32-bit values.
+type word32Slice []uint32
+
+func (v *word32Slice) Append(x uint32)    { *v = append(*v, x) }
+func (v *word32Slice) Len() int           { return len(*v) }
+func (v *word32Slice) Index(i int) uint32 { return (*v)[i] }
+
+// Word32Slice returns the address of a []int32, []uint32, []float32, or []enum field in the struct.
+func structPointer_Word32Slice(p structPointer, f field) *word32Slice {
+	return (*word32Slice)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+}
+
+// word64 is like word32 but for 64-bit values.
+type word64 **uint64
+
+func word64_Set(p word64, o *Buffer, x uint64) {
+	if len(o.uint64s) == 0 {
+		o.uint64s = make([]uint64, uint64PoolSize)
+	}
+	o.uint64s[0] = x
+	*p = &o.uint64s[0]
+	o.uint64s = o.uint64s[1:]
+}
+
+func word64_IsNil(p word64) bool {
+	return *p == nil
+}
+
+func word64_Get(p word64) uint64 {
+	return **p
+}
+
+func structPointer_Word64(p structPointer, f field) word64 {
+	return word64((**uint64)(unsafe.Pointer(uintptr(p) + uintptr(f))))
+}
+
+// word64Val is like word32Val but for 64-bit values.
+type word64Val *uint64
+
+func word64Val_Set(p word64Val, o *Buffer, x uint64) {
+	*p = x
+}
+
+func word64Val_Get(p word64Val) uint64 {
+	return *p
+}
+
+func structPointer_Word64Val(p structPointer, f field) word64Val {
+	return word64Val((*uint64)(unsafe.Pointer(uintptr(p) + uintptr(f))))
+}
+
+// word64Slice is like word32Slice but for 64-bit values.
+type word64Slice []uint64
+
+func (v *word64Slice) Append(x uint64)    { *v = append(*v, x) }
+func (v *word64Slice) Len() int           { return len(*v) }
+func (v *word64Slice) Index(i int) uint64 { return (*v)[i] }
+
+func structPointer_Word64Slice(p structPointer, f field) *word64Slice {
+	return (*word64Slice)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+}

go/vendor/github.com/golang/protobuf/proto/properties.go

+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2010 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
+
+/*
+ * Routines for encoding data into the wire format for protocol buffers.
+ */
+
+import (
+	"fmt"
+	"log"
+	"os"
+	"reflect"
+	"sort"
+	"strconv"
+	"strings"
+	"sync"
+)
+
+const debug bool = false
+
+// Constants that identify the encoding of a value on the wire.
+const (
+	WireVarint     = 0
+	WireFixed64    = 1
+	WireBytes      = 2
+	WireStartGroup = 3
+	WireEndGroup   = 4
+	WireFixed32    = 5
+)
+
+const startSize = 10 // initial slice/string sizes
+
+// Encoders are defined in encode.go
+// An encoder outputs the full representation of a field, including its
+// tag and encoder type.
+type encoder func(p *Buffer, prop *Properties, base structPointer) error
+
+// A valueEncoder encodes a single integer in a particular encoding.
+type valueEncoder func(o *Buffer, x uint64) error
+
+// Sizers are defined in encode.go
+// A sizer returns the encoded size of a field, including its tag and encoder
+// type.
+type sizer func(prop *Properties, base structPointer) int
+
+// A valueSizer returns the encoded size of a single integer in a particular
+// encoding.
+type valueSizer func(x uint64) int
+
+// Decoders are defined in decode.go
+// A decoder creates a value from its wire representation.
+// Unrecognized subelements are saved in unrec.
+type decoder func(p *Buffer, prop *Properties, base structPointer) error
+
+// A valueDecoder decodes a single integer in a particular encoding.
+type valueDecoder func(o *Buffer) (x uint64, err error)
+
+// A oneofMarshaler does the marshaling for all oneof fields in a message.
+type oneofMarshaler func(Message, *Buffer) error
+
+// A oneofUnmarshaler does the unmarshaling for a oneof field in a message.
+type oneofUnmarshaler func(Message, int, int, *Buffer) (bool, error)
+
+// A oneofSizer does the sizing for all oneof fields in a message.
+type oneofSizer func(Message) int
+
+// tagMap is an optimization over map[int]int for typical protocol buffer
+// use-cases. Encoded protocol buffers are often in tag order with small tag
+// numbers.
+type tagMap struct {
+	fastTags []int
+	slowTags map[int]int
+}
+
+// tagMapFastLimit is the upper bound on the tag number that will be stored in
+// the tagMap slice rather than its map.
+const tagMapFastLimit = 1024
+
+func (p *tagMap) get(t int) (int, bool) {
+	if t > 0 && t < tagMapFastLimit {
+		if t >= len(p.fastTags) {
+			return 0, false
+		}
+		fi := p.fastTags[t]
+		return fi, fi >= 0
+	}
+	fi, ok := p.slowTags[t]
+	return fi, ok
+}
+
+func (p *tagMap) put(t int, fi int) {
+	if t > 0 && t < tagMapFastLimit {
+		for len(p.fastTags) < t+1 {
+			p.fastTags = append(p.fastTags, -1)
+		}
+		p.fastTags[t] = fi
+		return
+	}
+	if p.slowTags == nil {
+		p.slowTags = make(map[int]int)
+	}
+	p.slowTags[t] = fi
+}
+
+// StructProperties represents properties for all the fields of a struct.
+// decoderTags and decoderOrigNames should only be used by the decoder.
+type StructProperties struct {
+	Prop             []*Properties  // properties for each field
+	reqCount         int            // required count
+	decoderTags      tagMap         // map from proto tag to struct field number
+	decoderOrigNames map[string]int // map from original name to struct field number
+	order            []int          // list of struct field numbers in tag order
+	unrecField       field          // field id of the XXX_unrecognized []byte field
+	extendable       bool           // is this an extendable proto
+
+	oneofMarshaler   oneofMarshaler
+	oneofUnmarshaler oneofUnmarshaler
+	oneofSizer       oneofSizer
+	stype            reflect.Type
+
+	// OneofTypes contains information about the oneof fields in this message.
+	// It is keyed by the original name of a field.
+	OneofTypes map[string]*OneofProperties
+}
+
+// OneofProperties represents information about a specific field in a oneof.
+type OneofProperties struct {
+	Type  reflect.Type // pointer to generated struct type for this oneof field
+	Field int          // struct field number of the containing oneof in the message
+	Prop  *Properties
+}
+
+// Implement the sorting interface so we can sort the fields in tag order, as recommended by the spec.
+// See encode.go, (*Buffer).enc_struct.
+
+func (sp *StructProperties) Len() int { return len(sp.order) }
+func (sp *StructProperties) Less(i, j int) bool {
+	return sp.Prop[sp.order[i]].Tag < sp.Prop[sp.order[j]].Tag
+}
+func (sp *StructProperties) Swap(i, j int) { sp.order[i], sp.order[j] = sp.order[j], sp.order[i] }
+
+// Properties represents the protocol-specific behavior of a single struct field.
+type Properties struct {
+	Name     string // name of the field, for error messages
+	OrigName string // original name before protocol compiler (always set)
+	JSONName string // name to use for JSON; determined by protoc
+	Wire     string
+	WireType int
+	Tag      int
+	Required bool
+	Optional bool
+	Repeated bool
+	Packed   bool   // relevant for repeated primitives only
+	Enum     string // set for enum types only
+	proto3   bool   // whether this is known to be a proto3 field; set for []byte only
+	oneof    bool   // whether this is a oneof field
+
+	Default    string // default value
+	HasDefault bool   // whether an explicit default was provided
+	def_uint64 uint64
+
+	enc           encoder
+	valEnc        valueEncoder // set for bool and numeric types only
+	field         field
+	tagcode       []byte // encoding of EncodeVarint((Tag<<3)|WireType)
+	tagbuf        [8]byte
+	stype         reflect.Type      // set for struct types only
+	sprop         *StructProperties // set for struct types only
+	isMarshaler   bool
+	isUnmarshaler bool
+
+	mtype    reflect.Type // set for map types only
+	mkeyprop *Properties  // set for map types only
+	mvalprop *Properties  // set for map types only
+
+	size    sizer
+	valSize valueSizer // set for bool and numeric types only
+
+	dec    decoder
+	valDec valueDecoder // set for bool and numeric types only
+
+	// If this is a packable field, this will be the decoder for the packed version of the field.
+	packedDec decoder
+}
+
+// String formats the properties in the protobuf struct field tag style.
+func (p *Properties) String() string {
+	s := p.Wire
+	s = ","
+	s += strconv.Itoa(p.Tag)
+	if p.Required {
+		s += ",req"
+	}
+	if p.Optional {
+		s += ",opt"
+	}
+	if p.Repeated {
+		s += ",rep"
+	}
+	if p.Packed {
+		s += ",packed"
+	}
+	s += ",name=" + p.OrigName
+	if p.JSONName != p.OrigName {
+		s += ",json=" + p.JSONName
+	}
+	if p.proto3 {
+		s += ",proto3"
+	}
+	if p.oneof {
+		s += ",oneof"
+	}
+	if len(p.Enum) > 0 {
+		s += ",enum=" + p.Enum
+	}
+	if p.HasDefault {
+		s += ",def=" + p.Default
+	}
+	return s
+}
+
+// Parse populates p by parsing a string in the protobuf struct field tag style.
+func (p *Properties) Parse(s string) {
+	// "bytes,49,opt,name=foo,def=hello!"
+	fields := strings.Split(s, ",") // breaks def=, but handled below.
+	if len(fields) < 2 {
+		fmt.Fprintf(os.Stderr, "proto: tag has too few fields: %q\n", s)
+		return
+	}
+
+	p.Wire = fields[0]
+	switch p.Wire {
+	case "varint":
+		p.WireType = WireVarint
+		p.valEnc = (*Buffer).EncodeVarint
+		p.valDec = (*Buffer).DecodeVarint
+		p.valSize = sizeVarint
+	case "fixed32":
+		p.WireType = WireFixed32
+		p.valEnc = (*Buffer).EncodeFixed32
+		p.valDec = (*Buffer).DecodeFixed32
+		p.valSize = sizeFixed32
+	case "fixed64":
+		p.WireType = WireFixed64
+		p.valEnc = (*Buffer).EncodeFixed64
+		p.valDec = (*Buffer).DecodeFixed64
+		p.valSize = sizeFixed64
+	case "zigzag32":
+		p.WireType = WireVarint
+		p.valEnc = (*Buffer).EncodeZigzag32
+		p.valDec = (*Buffer).DecodeZigzag32
+		p.valSize = sizeZigzag32
+	case "zigzag64":
+		p.WireType = WireVarint
+		p.valEnc = (*Buffer).EncodeZigzag64
+		p.valDec = (*Buffer).DecodeZigzag64
+		p.valSize = sizeZigzag64
+	case "bytes", "group":
+		p.WireType = WireBytes
+		// no numeric converter for non-numeric types
+	default:
+		fmt.Fprintf(os.Stderr, "proto: tag has unknown wire type: %q\n", s)
+		return
+	}
+
+	var err error
+	p.Tag, err = strconv.Atoi(fields[1])
+	if err != nil {
+		return
+	}
+
+	for i := 2; i < len(fields); i++ {
+		f := fields[i]
+		switch {
+		case f == "req":
+			p.Required = true
+		case f == "opt":
+			p.Optional = true
+		case f == "rep":
+			p.Repeated = true
+		case f == "packed":
+			p.Packed = true
+		case strings.HasPrefix(f, "name="):
+			p.OrigName = f[5:]
+		case strings.HasPrefix(f, "json="):
+			p.JSONName = f[5:]
+		case strings.HasPrefix(f, "enum="):
+			p.Enum = f[5:]
+		case f == "proto3":
+			p.proto3 = true
+		case f == "oneof":
+			p.oneof = true
+		case strings.HasPrefix(f, "def="):
+			p.HasDefault = true
+			p.Default = f[4:] // rest of string
+			if i+1 < len(fields) {
+				// Commas aren't escaped, and def is always last.
+				p.Default += "," + strings.Join(fields[i+1:], ",")
+				break
+			}
+		}
+	}
+}
+
+func logNoSliceEnc(t1, t2 reflect.Type) {
+	fmt.Fprintf(os.Stderr, "proto: no slice oenc for %T = []%T\n", t1, t2)
+}
+
+var protoMessageType = reflect.TypeOf((*Message)(nil)).Elem()
+
+// Initialize the fields for encoding and decoding.
+func (p *Properties) setEncAndDec(typ reflect.Type, f *reflect.StructField, lockGetProp bool) {
+	p.enc = nil
+	p.dec = nil
+	p.size = nil
+
+	switch t1 := typ; t1.Kind() {
+	default:
+		fmt.Fprintf(os.Stderr, "proto: no coders for %v\n", t1)
+
+	// proto3 scalar types
+
+	case reflect.Bool:
+		p.enc = (*Buffer).enc_proto3_bool
+		p.dec = (*Buffer).dec_proto3_bool
+		p.size = size_proto3_bool
+	case reflect.Int32:
+		p.enc = (*Buffer).enc_proto3_int32
+		p.dec = (*Buffer).dec_proto3_int32
+		p.size = size_proto3_int32
+	case reflect.Uint32:
+		p.enc = (*Buffer).enc_proto3_uint32
+		p.dec = (*Buffer).dec_proto3_int32 // can reuse
+		p.size = size_proto3_uint32
+	case reflect.Int64, reflect.Uint64:
+		p.enc = (*Buffer).enc_proto3_int64
+		p.dec = (*Buffer).dec_proto3_int64
+		p.size = size_proto3_int64
+	case reflect.Float32:
+		p.enc = (*Buffer).enc_proto3_uint32 // can just treat them as bits
+		p.dec = (*Buffer).dec_proto3_int32
+		p.size = size_proto3_uint32
+	case reflect.Float64:
+		p.enc = (*Buffer).enc_proto3_int64 // can just treat them as bits
+		p.dec = (*Buffer).dec_proto3_int64
+		p.size = size_proto3_int64
+	case reflect.String:
+		p.enc = (*Buffer).enc_proto3_string
+		p.dec = (*Buffer).dec_proto3_string
+		p.size = size_proto3_string
+
+	case reflect.Ptr:
+		switch t2 := t1.Elem(); t2.Kind() {
+		default:
+			fmt.Fprintf(os.Stderr, "proto: no encoder function for %v -> %v\n", t1, t2)
+			break
+		case reflect.Bool:
+			p.enc = (*Buffer).enc_bool
+			p.dec = (*Buffer).dec_bool
+			p.size = size_bool
+		case reflect.Int32:
+			p.enc = (*Buffer).enc_int32
+			p.dec = (*Buffer).dec_int32
+			p.size = size_int32
+		case reflect.Uint32:
+			p.enc = (*Buffer).enc_uint32
+			p.dec = (*Buffer).dec_int32 // can reuse
+			p.size = size_uint32
+		case reflect.Int64, reflect.Uint64:
+			p.enc = (*Buffer).enc_int64
+			p.dec = (*Buffer).dec_int64
+			p.size = size_int64
+		case reflect.Float32:
+			p.enc = (*Buffer).enc_uint32 // can just treat them as bits
+			p.dec = (*Buffer).dec_int32
+			p.size = size_uint32
+		case reflect.Float64:
+			p.enc = (*Buffer).enc_int64 // can just treat them as bits
+			p.dec = (*Buffer).dec_int64
+			p.size = size_int64
+		case reflect.String:
+			p.enc = (*Buffer).enc_string
+			p.dec = (*Buffer).dec_string
+			p.size = size_string
+		case reflect.Struct:
+			p.stype = t1.Elem()
+			p.isMarshaler = isMarshaler(t1)
+			p.isUnmarshaler = isUnmarshaler(t1)
+			if p.Wire == "bytes" {
+				p.enc = (*Buffer).enc_struct_message
+				p.dec = (*Buffer).dec_struct_message
+				p.size = size_struct_message
+			} else {
+				p.enc = (*Buffer).enc_struct_group
+				p.dec = (*Buffer).dec_struct_group
+				p.size = size_struct_group
+			}
+		}
+
+	case reflect.Slice:
+		switch t2 := t1.Elem(); t2.Kind() {
+		default:
+			logNoSliceEnc(t1, t2)
+			break
+		case reflect.Bool:
+			if p.Packed {
+				p.enc = (*Buffer).enc_slice_packed_bool
+				p.size = size_slice_packed_bool
+			} else {
+				p.enc = (*Buffer).enc_slice_bool
+				p.size = size_slice_bool
+			}
+			p.dec = (*Buffer).dec_slice_bool
+			p.packedDec = (*Buffer).dec_slice_packed_bool
+		case reflect.Int32:
+			if p.Packed {
+				p.enc = (*Buffer).enc_slice_packed_int32
+				p.size = size_slice_packed_int32
+			} else {
+				p.enc = (*Buffer).enc_slice_int32
+				p.size = size_slice_int32
+			}
+			p.dec = (*Buffer).dec_slice_int32
+			p.packedDec = (*Buffer).dec_slice_packed_int32
+		case reflect.Uint32:
+			if p.Packed {
+				p.enc = (*Buffer).enc_slice_packed_uint32
+				p.size = size_slice_packed_uint32
+			} else {
+				p.enc = (*Buffer).enc_slice_uint32
+				p.size = size_slice_uint32
+			}
+			p.dec = (*Buffer).dec_slice_int32
+			p.packedDec = (*Buffer).dec_slice_packed_int32
+		case reflect.Int64, reflect.Uint64:
+			if p.Packed {
+				p.enc = (*Buffer).enc_slice_packed_int64
+				p.size = size_slice_packed_int64
+			} else {
+				p.enc = (*Buffer).enc_slice_int64
+				p.size = size_slice_int64
+			}
+			p.dec = (*Buffer).dec_slice_int64
+			p.packedDec = (*Buffer).dec_slice_packed_int64
+		case reflect.Uint8:
+			p.dec = (*Buffer).dec_slice_byte
+			if p.proto3 {
+				p.enc = (*Buffer).enc_proto3_slice_byte
+				p.size = size_proto3_slice_byte
+			} else {
+				p.enc = (*Buffer).enc_slice_byte
+				p.size = size_slice_byte
+			}
+		case reflect.Float32, reflect.Float64:
+			switch t2.Bits() {
+			case 32:
+				// can just treat them as bits
+				if p.Packed {
+					p.enc = (*Buffer).enc_slice_packed_uint32
+					p.size = size_slice_packed_uint32
+				} else {
+					p.enc = (*Buffer).enc_slice_uint32
+					p.size = size_slice_uint32
+				}
+				p.dec = (*Buffer).dec_slice_int32
+				p.packedDec = (*Buffer).dec_slice_packed_int32
+			case 64:
+				// can just treat them as bits
+				if p.Packed {
+					p.enc = (*Buffer).enc_slice_packed_int64
+					p.size = size_slice_packed_int64
+				} else {
+					p.enc = (*Buffer).enc_slice_int64
+					p.size = size_slice_int64
+				}
+				p.dec = (*Buffer).dec_slice_int64
+				p.packedDec = (*Buffer).dec_slice_packed_int64
+			default:
+				logNoSliceEnc(t1, t2)
+				break
+			}
+		case reflect.String:
+			p.enc = (*Buffer).enc_slice_string
+			p.dec = (*Buffer).dec_slice_string
+			p.size = size_slice_string
+		case reflect.Ptr:
+			switch t3 := t2.Elem(); t3.Kind() {
+			default:
+				fmt.Fprintf(os.Stderr, "proto: no ptr oenc for %T -> %T -> %T\n", t1, t2, t3)
+				break
+			case reflect.Struct:
+				p.stype = t2.Elem()
+				p.isMarshaler = isMarshaler(t2)
+				p.isUnmarshaler = isUnmarshaler(t2)
+				if p.Wire == "bytes" {
+					p.enc = (*Buffer).enc_slice_struct_message
+					p.dec = (*Buffer).dec_slice_struct_message
+					p.size = size_slice_struct_message
+				} else {
+					p.enc = (*Buffer).enc_slice_struct_group
+					p.dec = (*Buffer).dec_slice_struct_group
+					p.size = size_slice_struct_group
+				}
+			}
+		case reflect.Slice:
+			switch t2.Elem().Kind() {
+			default:
+				fmt.Fprintf(os.Stderr, "proto: no slice elem oenc for %T -> %T -> %T\n", t1, t2, t2.Elem())
+				break
+			case reflect.Uint8:
+				p.enc = (*Buffer).enc_slice_slice_byte
+				p.dec = (*Buffer).dec_slice_slice_byte
+				p.size = size_slice_slice_byte
+			}
+		}
+
+	case reflect.Map:
+		p.enc = (*Buffer).enc_new_map
+		p.dec = (*Buffer).dec_new_map
+		p.size = size_new_map
+
+		p.mtype = t1
+		p.mkeyprop = &Properties{}
+		p.mkeyprop.init(reflect.PtrTo(p.mtype.Key()), "Key", f.Tag.Get("protobuf_key"), nil, lockGetProp)
+		p.mvalprop = &Properties{}
+		vtype := p.mtype.Elem()
+		if vtype.Kind() != reflect.Ptr && vtype.Kind() != reflect.Slice {
+			// The value type is not a message (*T) or bytes ([]byte),
+			// so we need encoders for the pointer to this type.
+			vtype = reflect.PtrTo(vtype)
+		}
+		p.mvalprop.init(vtype, "Value", f.Tag.Get("protobuf_val"), nil, lockGetProp)
+	}
+
+	// precalculate tag code
+	wire := p.WireType
+	if p.Packed {
+		wire = WireBytes
+	}
+	x := uint32(p.Tag)<<3 | uint32(wire)
+	i := 0
+	for i = 0; x > 127; i++ {
+		p.tagbuf[i] = 0x80 | uint8(x&0x7F)
+		x >>= 7
+	}
+	p.tagbuf[i] = uint8(x)
+	p.tagcode = p.tagbuf[0 : i+1]
+
+	if p.stype != nil {
+		if lockGetProp {
+			p.sprop = GetProperties(p.stype)
+		} else {
+			p.sprop = getPropertiesLocked(p.stype)
+		}
+	}
+}
+
+var (
+	marshalerType   = reflect.TypeOf((*Marshaler)(nil)).Elem()
+	unmarshalerType = reflect.TypeOf((*Unmarshaler)(nil)).Elem()
+)
+
+// isMarshaler reports whether type t implements Marshaler.
+func isMarshaler(t reflect.Type) bool {
+	// We're checking for (likely) pointer-receiver methods
+	// so if t is not a pointer, something is very wrong.
+	// The calls above only invoke isMarshaler on pointer types.
+	if t.Kind() != reflect.Ptr {
+		panic("proto: misuse of isMarshaler")
+	}
+	return t.Implements(marshalerType)
+}
+
+// isUnmarshaler reports whether type t implements Unmarshaler.
+func isUnmarshaler(t reflect.Type) bool {
+	// We're checking for (likely) pointer-receiver methods
+	// so if t is not a pointer, something is very wrong.
+	// The calls above only invoke isUnmarshaler on pointer types.
+	if t.Kind() != reflect.Ptr {
+		panic("proto: misuse of isUnmarshaler")
+	}
+	return t.Implements(unmarshalerType)
+}
+
+// Init populates the properties from a protocol buffer struct tag.
+func (p *Properties) Init(typ reflect.Type, name, tag string, f *reflect.StructField) {
+	p.init(typ, name, tag, f, true)
+}
+
+func (p *Properties) init(typ reflect.Type, name, tag string, f *reflect.StructField, lockGetProp bool) {
+	// "bytes,49,opt,def=hello!"
+	p.Name = name
+	p.OrigName = name
+	if f != nil {
+		p.field = toField(f)
+	}
+	if tag == "" {
+		return
+	}
+	p.Parse(tag)
+	p.setEncAndDec(typ, f, lockGetProp)
+}
+
+var (
+	propertiesMu  sync.RWMutex
+	propertiesMap = make(map[reflect.Type]*StructProperties)
+)
+
+// GetProperties returns the list of properties for the type represented by t.
+// t must represent a generated struct type of a protocol message.
+func GetProperties(t reflect.Type) *StructProperties {
+	if t.Kind() != reflect.Struct {
+		panic("proto: type must have kind struct")
+	}
+
+	// Most calls to GetProperties in a long-running program will be
+	// retrieving details for types we have seen before.
+	propertiesMu.RLock()
+	sprop, ok := propertiesMap[t]
+	propertiesMu.RUnlock()
+	if ok {
+		if collectStats {
+			stats.Chit++
+		}
+		return sprop
+	}
+
+	propertiesMu.Lock()
+	sprop = getPropertiesLocked(t)
+	propertiesMu.Unlock()
+	return sprop
+}
+
+// getPropertiesLocked requires that propertiesMu is held.
+func getPropertiesLocked(t reflect.Type) *StructProperties {
+	if prop, ok := propertiesMap[t]; ok {
+		if collectStats {
+			stats.Chit++
+		}
+		return prop
+	}
+	if collectStats {
+		stats.Cmiss++
+	}
+
+	prop := new(StructProperties)
+	// in case of recursive protos, fill this in now.
+	propertiesMap[t] = prop
+
+	// build properties
+	prop.extendable = reflect.PtrTo(t).Implements(extendableProtoType) ||
+		reflect.PtrTo(t).Implements(extendableProtoV1Type)
+	prop.unrecField = invalidField
+	prop.Prop = make([]*Properties, t.NumField())
+	prop.order = make([]int, t.NumField())
+
+	for i := 0; i < t.NumField(); i++ {
+		f := t.Field(i)
+		p := new(Properties)
+		name := f.Name
+		p.init(f.Type, name, f.Tag.Get("protobuf"), &f, false)
+
+		if f.Name == "XXX_InternalExtensions" { // special case
+			p.enc = (*Buffer).enc_exts
+			p.dec = nil // not needed
+			p.size = size_exts
+		} else if f.Name == "XXX_extensions" { // special case
+			p.enc = (*Buffer).enc_map
+			p.dec = nil // not needed
+			p.size = size_map
+		} else if f.Name == "XXX_unrecognized" { // special case
+			prop.unrecField = toField(&f)
+		}
+		oneof := f.Tag.Get("protobuf_oneof") // special case
+		if oneof != "" {
+			// Oneof fields don't use the traditional protobuf tag.
+			p.OrigName = oneof
+		}
+		prop.Prop[i] = p
+		prop.order[i] = i
+		if debug {
+			print(i, " ", f.Name, " ", t.String(), " ")
+			if p.Tag > 0 {
+				print(p.String())
+			}
+			print("\n")
+		}
+		if p.enc == nil && !strings.HasPrefix(f.Name, "XXX_") && oneof == "" {
+			fmt.Fprintln(os.Stderr, "proto: no encoder for", f.Name, f.Type.String(), "[GetProperties]")
+		}
+	}
+
+	// Re-order prop.order.
+	sort.Sort(prop)
+
+	type oneofMessage interface {
+		XXX_OneofFuncs() (func(Message, *Buffer) error, func(Message, int, int, *Buffer) (bool, error), func(Message) int, []interface{})
+	}
+	if om, ok := reflect.Zero(reflect.PtrTo(t)).Interface().(oneofMessage); ok {
+		var oots []interface{}
+		prop.oneofMarshaler, prop.oneofUnmarshaler, prop.oneofSizer, oots = om.XXX_OneofFuncs()
+		prop.stype = t
+
+		// Interpret oneof metadata.
+		prop.OneofTypes = make(map[string]*OneofProperties)
+		for _, oot := range oots {
+			oop := &OneofProperties{
+				Type: reflect.ValueOf(oot).Type(), // *T
+				Prop: new(Properties),
+			}
+			sft := oop.Type.Elem().Field(0)
+			oop.Prop.Name = sft.Name
+			oop.Prop.Parse(sft.Tag.Get("protobuf"))
+			// There will be exactly one interface field that
+			// this new value is assignable to.
+			for i := 0; i < t.NumField(); i++ {
+				f := t.Field(i)
+				if f.Type.Kind() != reflect.Interface {
+					continue
+				}
+				if !oop.Type.AssignableTo(f.Type) {
+					continue
+				}
+				oop.Field = i
+				break
+			}
+			prop.OneofTypes[oop.Prop.OrigName] = oop
+		}
+	}
+
+	// build required counts
+	// build tags
+	reqCount := 0
+	prop.decoderOrigNames = make(map[string]int)
+	for i, p := range prop.Prop {
+		if strings.HasPrefix(p.Name, "XXX_") {
+			// Internal fields should not appear in tags/origNames maps.
+			// They are handled specially when encoding and decoding.
+			continue
+		}
+		if p.Required {
+			reqCount++
+		}
+		prop.decoderTags.put(p.Tag, i)
+		prop.decoderOrigNames[p.OrigName] = i
+	}
+	prop.reqCount = reqCount
+
+	return prop
+}
+
+// Return the Properties object for the x[0]'th field of the structure.
+func propByIndex(t reflect.Type, x []int) *Properties {
+	if len(x) != 1 {
+		fmt.Fprintf(os.Stderr, "proto: field index dimension %d (not 1) for type %s\n", len(x), t)
+		return nil
+	}
+	prop := GetProperties(t)
+	return prop.Prop[x[0]]
+}
+
+// Get the address and type of a pointer to a struct from an interface.
+func getbase(pb Message) (t reflect.Type, b structPointer, err error) {
+	if pb == nil {
+		err = ErrNil
+		return
+	}
+	// get the reflect type of the pointer to the struct.
+	t = reflect.TypeOf(pb)
+	// get the address of the struct.
+	value := reflect.ValueOf(pb)
+	b = toStructPointer(value)
+	return
+}
+
+// A global registry of enum types.
+// The generated code will register the generated maps by calling RegisterEnum.
+
+var enumValueMaps = make(map[string]map[string]int32)
+
+// RegisterEnum is called from the generated code to install the enum descriptor
+// maps into the global table to aid parsing text format protocol buffers.
+func RegisterEnum(typeName string, unusedNameMap map[int32]string, valueMap map[string]int32) {
+	if _, ok := enumValueMaps[typeName]; ok {
+		panic("proto: duplicate enum registered: " + typeName)
+	}
+	enumValueMaps[typeName] = valueMap
+}
+
+// EnumValueMap returns the mapping from names to integers of the
+// enum type enumType, or a nil if not found.
+func EnumValueMap(enumType string) map[string]int32 {
+	return enumValueMaps[enumType]
+}
+
+// A registry of all linked message types.
+// The string is a fully-qualified proto name ("pkg.Message").
+var (
+	protoTypes    = make(map[string]reflect.Type)
+	revProtoTypes = make(map[reflect.Type]string)
+)
+
+// RegisterType is called from generated code and maps from the fully qualified
+// proto name to the type (pointer to struct) of the protocol buffer.
+func RegisterType(x Message, name string) {
+	if _, ok := protoTypes[name]; ok {
+		// TODO: Some day, make this a panic.
+		log.Printf("proto: duplicate proto type registered: %s", name)
+		return
+	}
+	t := reflect.TypeOf(x)
+	protoTypes[name] = t
+	revProtoTypes[t] = name
+}
+
+// MessageName returns the fully-qualified proto name for the given message type.
+func MessageName(x Message) string {
+	type xname interface {
+		XXX_MessageName() string
+	}
+	if m, ok := x.(xname); ok {
+		return m.XXX_MessageName()
+	}
+	return revProtoTypes[reflect.TypeOf(x)]
+}
+
+// MessageType returns the message type (pointer to struct) for a named message.
+func MessageType(name string) reflect.Type { return protoTypes[name] }
+
+// A registry of all linked proto files.
+var (
+	protoFiles = make(map[string][]byte) // file name => fileDescriptor
+)
+
+// RegisterFile is called from generated code and maps from the
+// full file name of a .proto file to its compressed FileDescriptorProto.
+func RegisterFile(filename string, fileDescriptor []byte) {
+	protoFiles[filename] = fileDescriptor
+}
+
+// FileDescriptor returns the compressed FileDescriptorProto for a .proto file.
+func FileDescriptor(filename string) []byte { return protoFiles[filename] }

go/vendor/github.com/golang/protobuf/proto/text.go

+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2010 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
+
+// Functions for writing the text protocol buffer format.
+
+import (
+	"bufio"
+	"bytes"
+	"encoding"
+	"errors"
+	"fmt"
+	"io"
+	"log"
+	"math"
+	"reflect"
+	"sort"
+	"strings"
+)
+
+var (
+	newline         = []byte("\n")
+	spaces          = []byte("                                        ")
+	gtNewline       = []byte(">\n")
+	endBraceNewline = []byte("}\n")
+	backslashN      = []byte{'\\', 'n'}
+	backslashR      = []byte{'\\', 'r'}
+	backslashT      = []byte{'\\', 't'}
+	backslashDQ     = []byte{'\\', '"'}
+	backslashBS     = []byte{'\\', '\\'}
+	posInf          = []byte("inf")
+	negInf          = []byte("-inf")
+	nan             = []byte("nan")
+)
+
+type writer interface {
+	io.Writer
+	WriteByte(byte) error
+}
+
+// textWriter is an io.Writer that tracks its indentation level.
+type textWriter struct {
+	ind      int
+	complete bool // if the current position is a complete line
+	compact  bool // whether to write out as a one-liner
+	w        writer
+}
+
+func (w *textWriter) WriteString(s string) (n int, err error) {
+	if !strings.Contains(s, "\n") {
+		if !w.compact && w.complete {
+			w.writeIndent()
+		}
+		w.complete = false
+		return io.WriteString(w.w, s)
+	}
+	// WriteString is typically called without newlines, so this
+	// codepath and its copy are rare.  We copy to avoid
+	// duplicating all of Write's logic here.
+	return w.Write([]byte(s))
+}
+
+func (w *textWriter) Write(p []byte) (n int, err error) {
+	newlines := bytes.Count(p, newline)
+	if newlines == 0 {
+		if !w.compact && w.complete {
+			w.writeIndent()
+		}
+		n, err = w.w.Write(p)
+		w.complete = false
+		return n, err
+	}
+
+	frags := bytes.SplitN(p, newline, newlines+1)
+	if w.compact {
+		for i, frag := range frags {
+			if i > 0 {
+				if err := w.w.WriteByte(' '); err != nil {
+					return n, err
+				}
+				n++
+			}
+			nn, err := w.w.Write(frag)
+			n += nn
+			if err != nil {
+				return n, err
+			}
+		}
+		return n, nil
+	}
+
+	for i, frag := range frags {
+		if w.complete {
+			w.writeIndent()
+		}
+		nn, err := w.w.Write(frag)
+		n += nn
+		if err != nil {
+			return n, err
+		}
+		if i+1 < len(frags) {
+			if err := w.w.WriteByte('\n'); err != nil {
+				return n, err
+			}
+			n++
+		}
+	}
+	w.complete = len(frags[len(frags)-1]) == 0
+	return n, nil
+}
+
+func (w *textWriter) WriteByte(c byte) error {
+	if w.compact && c == '\n' {
+		c = ' '
+	}
+	if !w.compact && w.complete {
+		w.writeIndent()
+	}
+	err := w.w.WriteByte(c)
+	w.complete = c == '\n'
+	return err
+}
+
+func (w *textWriter) indent() { w.ind++ }
+
+func (w *textWriter) unindent() {
+	if w.ind == 0 {
+		log.Print("proto: textWriter unindented too far")
+		return
+	}
+	w.ind--
+}
+
+func writeName(w *textWriter, props *Properties) error {
+	if _, err := w.WriteString(props.OrigName); err != nil {
+		return err
+	}
+	if props.Wire != "group" {
+		return w.WriteByte(':')
+	}
+	return nil
+}
+
+// raw is the interface satisfied by RawMessage.
+type raw interface {
+	Bytes() []byte
+}
+
+func requiresQuotes(u string) bool {
+	// When type URL contains any characters except [0-9A-Za-z./\-]*, it must be quoted.
+	for _, ch := range u {
+		switch {
+		case ch == '.' || ch == '/' || ch == '_':
+			continue
+		case '0' <= ch && ch <= '9':
+			continue
+		case 'A' <= ch && ch <= 'Z':
+			continue
+		case 'a' <= ch && ch <= 'z':
+			continue
+		default:
+			return true
+		}
+	}
+	return false
+}
+
+// isAny reports whether sv is a google.protobuf.Any message
+func isAny(sv reflect.Value) bool {
+	type wkt interface {
+		XXX_WellKnownType() string
+	}
+	t, ok := sv.Addr().Interface().(wkt)
+	return ok && t.XXX_WellKnownType() == "Any"
+}
+
+// writeProto3Any writes an expanded google.protobuf.Any message.
+//
+// It returns (false, nil) if sv value can't be unmarshaled (e.g. because
+// required messages are not linked in).
+//
+// It returns (true, error) when sv was written in expanded format or an error
+// was encountered.
+func (tm *TextMarshaler) writeProto3Any(w *textWriter, sv reflect.Value) (bool, error) {
+	turl := sv.FieldByName("TypeUrl")
+	val := sv.FieldByName("Value")
+	if !turl.IsValid() || !val.IsValid() {
+		return true, errors.New("proto: invalid google.protobuf.Any message")
+	}
+
+	b, ok := val.Interface().([]byte)
+	if !ok {
+		return true, errors.New("proto: invalid google.protobuf.Any message")
+	}
+
+	parts := strings.Split(turl.String(), "/")
+	mt := MessageType(parts[len(parts)-1])
+	if mt == nil {
+		return false, nil
+	}
+	m := reflect.New(mt.Elem())
+	if err := Unmarshal(b, m.Interface().(Message)); err != nil {
+		return false, nil
+	}
+	w.Write([]byte("["))
+	u := turl.String()
+	if requiresQuotes(u) {
+		writeString(w, u)
+	} else {
+		w.Write([]byte(u))
+	}
+	if w.compact {
+		w.Write([]byte("]:<"))
+	} else {
+		w.Write([]byte("]: <\n"))
+		w.ind++
+	}
+	if err := tm.writeStruct(w, m.Elem()); err != nil {
+		return true, err
+	}
+	if w.compact {
+		w.Write([]byte("> "))
+	} else {
+		w.ind--
+		w.Write([]byte(">\n"))
+	}
+	return true, nil
+}
+
+func (tm *TextMarshaler) writeStruct(w *textWriter, sv reflect.Value) error {
+	if tm.ExpandAny && isAny(sv) {
+		if canExpand, err := tm.writeProto3Any(w, sv); canExpand {
+			return err
+		}
+	}
+	st := sv.Type()
+	sprops := GetProperties(st)
+	for i := 0; i < sv.NumField(); i++ {
+		fv := sv.Field(i)
+		props := sprops.Prop[i]
+		name := st.Field(i).Name
+
+		if strings.HasPrefix(name, "XXX_") {
+			// There are two XXX_ fields:
+			//   XXX_unrecognized []byte
+			//   XXX_extensions   map[int32]proto.Extension
+			// The first is handled here;
+			// the second is handled at the bottom of this function.
+			if name == "XXX_unrecognized" && !fv.IsNil() {
+				if err := writeUnknownStruct(w, fv.Interface().([]byte)); err != nil {
+					return err
+				}
+			}
+			continue
+		}
+		if fv.Kind() == reflect.Ptr && fv.IsNil() {
+			// Field not filled in. This could be an optional field or
+			// a required field that wasn't filled in. Either way, there
+			// isn't anything we can show for it.
+			continue
+		}
+		if fv.Kind() == reflect.Slice && fv.IsNil() {
+			// Repeated field that is empty, or a bytes field that is unused.
+			continue
+		}
+
+		if props.Repeated && fv.Kind() == reflect.Slice {
+			// Repeated field.
+			for j := 0; j < fv.Len(); j++ {
+				if err := writeName(w, props); err != nil {
+					return err
+				}
+				if !w.compact {
+					if err := w.WriteByte(' '); err != nil {
+						return err
+					}
+				}
+				v := fv.Index(j)
+				if v.Kind() == reflect.Ptr && v.IsNil() {
+					// A nil message in a repeated field is not valid,
+					// but we can handle that more gracefully than panicking.
+					if _, err := w.Write([]byte("<nil>\n")); err != nil {
+						return err
+					}
+					continue
+				}
+				if err := tm.writeAny(w, v, props); err != nil {
+					return err
+				}
+				if err := w.WriteByte('\n'); err != nil {
+					return err
+				}
+			}
+			continue
+		}
+		if fv.Kind() == reflect.Map {
+			// Map fields are rendered as a repeated struct with key/value fields.
+			keys := fv.MapKeys()
+			sort.Sort(mapKeys(keys))
+			for _, key := range keys {
+				val := fv.MapIndex(key)
+				if err := writeName(w, props); err != nil {
+					return err
+				}
+				if !w.compact {
+					if err := w.WriteByte(' '); err != nil {
+						return err
+					}
+				}
+				// open struct
+				if err := w.WriteByte('<'); err != nil {
+					return err
+				}
+				if !w.compact {
+					if err := w.WriteByte('\n'); err != nil {
+						return err
+					}
+				}
+				w.indent()
+				// key
+				if _, err := w.WriteString("key:"); err != nil {
+					return err
+				}
+				if !w.compact {
+					if err := w.WriteByte(' '); err != nil {
+						return err
+					}
+				}
+				if err := tm.writeAny(w, key, props.mkeyprop); err != nil {
+					return err
+				}
+				if err := w.WriteByte('\n'); err != nil {
+					return err
+				}
+				// nil values aren't legal, but we can avoid panicking because of them.
+				if val.Kind() != reflect.Ptr || !val.IsNil() {
+					// value
+					if _, err := w.WriteString("value:"); err != nil {
+						return err
+					}
+					if !w.compact {
+						if err := w.WriteByte(' '); err != nil {
+							return err
+						}
+					}
+					if err := tm.writeAny(w, val, props.mvalprop); err != nil {
+						return err
+					}
+					if err := w.WriteByte('\n'); err != nil {
+						return err
+					}
+				}
+				// close struct
+				w.unindent()
+				if err := w.WriteByte('>'); err != nil {
+					return err
+				}
+				if err := w.WriteByte('\n'); err != nil {
+					return err
+				}
+			}
+			continue
+		}
+		if props.proto3 && fv.Kind() == reflect.Slice && fv.Len() == 0 {
+			// empty bytes field
+			continue
+		}
+		if fv.Kind() != reflect.Ptr && fv.Kind() != reflect.Slice {
+			// proto3 non-repeated scalar field; skip if zero value
+			if isProto3Zero(fv) {
+				continue
+			}
+		}
+
+		if fv.Kind() == reflect.Interface {
+			// Check if it is a oneof.
+			if st.Field(i).Tag.Get("protobuf_oneof") != "" {
+				// fv is nil, or holds a pointer to generated struct.
+				// That generated struct has exactly one field,
+				// which has a protobuf struct tag.
+				if fv.IsNil() {
+					continue
+				}
+				inner := fv.Elem().Elem() // interface -> *T -> T
+				tag := inner.Type().Field(0).Tag.Get("protobuf")
+				props = new(Properties) // Overwrite the outer props var, but not its pointee.
+				props.Parse(tag)
+				// Write the value in the oneof, not the oneof itself.
+				fv = inner.Field(0)
+
+				// Special case to cope with malformed messages gracefully:
+				// If the value in the oneof is a nil pointer, don't panic
+				// in writeAny.
+				if fv.Kind() == reflect.Ptr && fv.IsNil() {
+					// Use errors.New so writeAny won't render quotes.
+					msg := errors.New("/* nil */")
+					fv = reflect.ValueOf(&msg).Elem()
+				}
+			}
+		}
+
+		if err := writeName(w, props); err != nil {
+			return err
+		}
+		if !w.compact {
+			if err := w.WriteByte(' '); err != nil {
+				return err
+			}
+		}
+		if b, ok := fv.Interface().(raw); ok {
+			if err := writeRaw(w, b.Bytes()); err != nil {
+				return err
+			}
+			continue
+		}
+
+		// Enums have a String method, so writeAny will work fine.
+		if err := tm.writeAny(w, fv, props); err != nil {
+			return err
+		}
+
+		if err := w.WriteByte('\n'); err != nil {
+			return err
+		}
+	}
+
+	// Extensions (the XXX_extensions field).
+	pv := sv.Addr()
+	if _, ok := extendable(pv.Interface()); ok {
+		if err := tm.writeExtensions(w, pv); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+// writeRaw writes an uninterpreted raw message.
+func writeRaw(w *textWriter, b []byte) error {
+	if err := w.WriteByte('<'); err != nil {
+		return err
+	}
+	if !w.compact {
+		if err := w.WriteByte('\n'); err != nil {
+			return err
+		}
+	}
+	w.indent()
+	if err := writeUnknownStruct(w, b); err != nil {
+		return err
+	}
+	w.unindent()
+	if err := w.WriteByte('>'); err != nil {
+		return err
+	}
+	return nil
+}
+
+// writeAny writes an arbitrary field.
+func (tm *TextMarshaler) writeAny(w *textWriter, v reflect.Value, props *Properties) error {
+	v = reflect.Indirect(v)
+
+	// Floats have special cases.
+	if v.Kind() == reflect.Float32 || v.Kind() == reflect.Float64 {
+		x := v.Float()
+		var b []byte
+		switch {
+		case math.IsInf(x, 1):
+			b = posInf
+		case math.IsInf(x, -1):
+			b = negInf
+		case math.IsNaN(x):
+			b = nan
+		}
+		if b != nil {
+			_, err := w.Write(b)
+			return err
+		}
+		// Other values are handled below.
+	}
+
+	// We don't attempt to serialise every possible value type; only those
+	// that can occur in protocol buffers.
+	switch v.Kind() {
+	case reflect.Slice:
+		// Should only be a []byte; repeated fields are handled in writeStruct.
+		if err := writeString(w, string(v.Bytes())); err != nil {
+			return err
+		}
+	case reflect.String:
+		if err := writeString(w, v.String()); err != nil {
+			return err
+		}
+	case reflect.Struct:
+		// Required/optional group/message.
+		var bra, ket byte = '<', '>'
+		if props != nil && props.Wire == "group" {
+			bra, ket = '{', '}'
+		}
+		if err := w.WriteByte(bra); err != nil {
+			return err
+		}
+		if !w.compact {
+			if err := w.WriteByte('\n'); err != nil {
+				return err
+			}
+		}
+		w.indent()
+		if etm, ok := v.Interface().(encoding.TextMarshaler); ok {
+			text, err := etm.MarshalText()
+			if err != nil {
+				return err
+			}
+			if _, err = w.Write(text); err != nil {
+				return err
+			}
+		} else if err := tm.writeStruct(w, v); err != nil {
+			return err
+		}
+		w.unindent()
+		if err := w.WriteByte(ket); err != nil {
+			return err
+		}
+	default:
+		_, err := fmt.Fprint(w, v.Interface())
+		return err
+	}
+	return nil
+}
+
+// equivalent to C's isprint.
+func isprint(c byte) bool {
+	return c >= 0x20 && c < 0x7f
+}
+
+// writeString writes a string in the protocol buffer text format.
+// It is similar to strconv.Quote except we don't use Go escape sequences,
+// we treat the string as a byte sequence, and we use octal escapes.
+// These differences are to maintain interoperability with the other
+// languages' implementations of the text format.
+func writeString(w *textWriter, s string) error {
+	// use WriteByte here to get any needed indent
+	if err := w.WriteByte('"'); err != nil {
+		return err
+	}
+	// Loop over the bytes, not the runes.
+	for i := 0; i < len(s); i++ {
+		var err error
+		// Divergence from C++: we don't escape apostrophes.
+		// There's no need to escape them, and the C++ parser
+		// copes with a naked apostrophe.
+		switch c := s[i]; c {
+		case '\n':
+			_, err = w.w.Write(backslashN)
+		case '\r':
+			_, err = w.w.Write(backslashR)
+		case '\t':
+			_, err = w.w.Write(backslashT)
+		case '"':
+			_, err = w.w.Write(backslashDQ)
+		case '\\':
+			_, err = w.w.Write(backslashBS)
+		default:
+			if isprint(c) {
+				err = w.w.WriteByte(c)
+			} else {
+				_, err = fmt.Fprintf(w.w, "\\%03o", c)
+			}
+		}
+		if err != nil {
+			return err
+		}
+	}
+	return w.WriteByte('"')
+}
+
+func writeUnknownStruct(w *textWriter, data []byte) (err error) {
+	if !w.compact {
+		if _, err := fmt.Fprintf(w, "/* %d unknown bytes */\n", len(data)); err != nil {
+			return err
+		}
+	}
+	b := NewBuffer(data)
+	for b.index < len(b.buf) {
+		x, err := b.DecodeVarint()
+		if err != nil {
+			_, err := fmt.Fprintf(w, "/* %v */\n", err)
+			return err
+		}
+		wire, tag := x&7, x>>3
+		if wire == WireEndGroup {
+			w.unindent()
+			if _, err := w.Write(endBraceNewline); err != nil {
+				return err
+			}
+			continue
+		}
+		if _, err := fmt.Fprint(w, tag); err != nil {
+			return err
+		}
+		if wire != WireStartGroup {
+			if err := w.WriteByte(':'); err != nil {
+				return err
+			}
+		}
+		if !w.compact || wire == WireStartGroup {
+			if err := w.WriteByte(' '); err != nil {
+				return err
+			}
+		}
+		switch wire {
+		case WireBytes:
+			buf, e := b.DecodeRawBytes(false)
+			if e == nil {
+				_, err = fmt.Fprintf(w, "%q", buf)
+			} else {
+				_, err = fmt.Fprintf(w, "/* %v */", e)
+			}
+		case WireFixed32:
+			x, err = b.DecodeFixed32()
+			err = writeUnknownInt(w, x, err)
+		case WireFixed64:
+			x, err = b.DecodeFixed64()
+			err = writeUnknownInt(w, x, err)
+		case WireStartGroup:
+			err = w.WriteByte('{')
+			w.indent()
+		case WireVarint:
+			x, err = b.DecodeVarint()
+			err = writeUnknownInt(w, x, err)
+		default:
+			_, err = fmt.Fprintf(w, "/* unknown wire type %d */", wire)
+		}
+		if err != nil {
+			return err
+		}
+		if err = w.WriteByte('\n'); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func writeUnknownInt(w *textWriter, x uint64, err error) error {
+	if err == nil {
+		_, err = fmt.Fprint(w, x)
+	} else {
+		_, err = fmt.Fprintf(w, "/* %v */", err)
+	}
+	return err
+}
+
+type int32Slice []int32
+
+func (s int32Slice) Len() int           { return len(s) }
+func (s int32Slice) Less(i, j int) bool { return s[i] < s[j] }
+func (s int32Slice) Swap(i, j int)      { s[i], s[j] = s[j], s[i] }
+
+// writeExtensions writes all the extensions in pv.
+// pv is assumed to be a pointer to a protocol message struct that is extendable.
+func (tm *TextMarshaler) writeExtensions(w *textWriter, pv reflect.Value) error {
+	emap := extensionMaps[pv.Type().Elem()]
+	ep, _ := extendable(pv.Interface())
+
+	// Order the extensions by ID.
+	// This isn't strictly necessary, but it will give us
+	// canonical output, which will also make testing easier.
+	m, mu := ep.extensionsRead()
+	if m == nil {
+		return nil
+	}
+	mu.Lock()
+	ids := make([]int32, 0, len(m))
+	for id := range m {
+		ids = append(ids, id)
+	}
+	sort.Sort(int32Slice(ids))
+	mu.Unlock()
+
+	for _, extNum := range ids {
+		ext := m[extNum]
+		var desc *ExtensionDesc
+		if emap != nil {
+			desc = emap[extNum]
+		}
+		if desc == nil {
+			// Unknown extension.
+			if err := writeUnknownStruct(w, ext.enc); err != nil {
+				return err
+			}
+			continue
+		}
+
+		pb, err := GetExtension(ep, desc)
+		if err != nil {
+			return fmt.Errorf("failed getting extension: %v", err)
+		}
+
+		// Repeated extensions will appear as a slice.
+		if !desc.repeated() {
+			if err := tm.writeExtension(w, desc.Name, pb); err != nil {
+				return err
+			}
+		} else {
+			v := reflect.ValueOf(pb)
+			for i := 0; i < v.Len(); i++ {
+				if err := tm.writeExtension(w, desc.Name, v.Index(i).Interface()); err != nil {
+					return err
+				}
+			}
+		}
+	}
+	return nil
+}
+
+func (tm *TextMarshaler) writeExtension(w *textWriter, name string, pb interface{}) error {
+	if _, err := fmt.Fprintf(w, "[%s]:", name); err != nil {
+		return err
+	}
+	if !w.compact {
+		if err := w.WriteByte(' '); err != nil {
+			return err
+		}
+	}
+	if err := tm.writeAny(w, reflect.ValueOf(pb), nil); err != nil {
+		return err
+	}
+	if err := w.WriteByte('\n'); err != nil {
+		return err
+	}
+	return nil
+}
+
+func (w *textWriter) writeIndent() {
+	if !w.complete {
+		return
+	}
+	remain := w.ind * 2
+	for remain > 0 {
+		n := remain
+		if n > len(spaces) {
+			n = len(spaces)
+		}
+		w.w.Write(spaces[:n])
+		remain -= n
+	}
+	w.complete = false
+}
+
+// TextMarshaler is a configurable text format marshaler.
+type TextMarshaler struct {
+	Compact   bool // use compact text format (one line).
+	ExpandAny bool // expand google.protobuf.Any messages of known types
+}
+
+// Marshal writes a given protocol buffer in text format.
+// The only errors returned are from w.
+func (tm *TextMarshaler) Marshal(w io.Writer, pb Message) error {
+	val := reflect.ValueOf(pb)
+	if pb == nil || val.IsNil() {
+		w.Write([]byte("<nil>"))
+		return nil
+	}
+	var bw *bufio.Writer
+	ww, ok := w.(writer)
+	if !ok {
+		bw = bufio.NewWriter(w)
+		ww = bw
+	}
+	aw := &textWriter{
+		w:        ww,
+		complete: true,
+		compact:  tm.Compact,
+	}
+
+	if etm, ok := pb.(encoding.TextMarshaler); ok {
+		text, err := etm.MarshalText()
+		if err != nil {
+			return err
+		}
+		if _, err = aw.Write(text); err != nil {
+			return err
+		}
+		if bw != nil {
+			return bw.Flush()
+		}
+		return nil
+	}
+	// Dereference the received pointer so we don't have outer < and >.
+	v := reflect.Indirect(val)
+	if err := tm.writeStruct(aw, v); err != nil {
+		return err
+	}
+	if bw != nil {
+		return bw.Flush()
+	}
+	return nil
+}
+
+// Text is the same as Marshal, but returns the string directly.
+func (tm *TextMarshaler) Text(pb Message) string {
+	var buf bytes.Buffer
+	tm.Marshal(&buf, pb)
+	return buf.String()
+}
+
+var (
+	defaultTextMarshaler = TextMarshaler{}
+	compactTextMarshaler = TextMarshaler{Compact: true}
+)
+
+// TODO: consider removing some of the Marshal functions below.
+
+// MarshalText writes a given protocol buffer in text format.
+// The only errors returned are from w.
+func MarshalText(w io.Writer, pb Message) error { return defaultTextMarshaler.Marshal(w, pb) }
+
+// MarshalTextString is the same as MarshalText, but returns the string directly.
+func MarshalTextString(pb Message) string { return defaultTextMarshaler.Text(pb) }
+
+// CompactText writes a given protocol buffer in compact text format (one line).
+func CompactText(w io.Writer, pb Message) error { return compactTextMarshaler.Marshal(w, pb) }
+
+// CompactTextString is the same as CompactText, but returns the string directly.
+func CompactTextString(pb Message) string { return compactTextMarshaler.Text(pb) }

go/vendor/github.com/golang/protobuf/proto/text_parser.go

+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2010 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
+
+// Functions for parsing the Text protocol buffer format.
+// TODO: message sets.
+
+import (
+	"encoding"
+	"errors"
+	"fmt"
+	"reflect"
+	"strconv"
+	"strings"
+	"unicode/utf8"
+)
+
+// Error string emitted when deserializing Any and fields are already set
+const anyRepeatedlyUnpacked = "Any message unpacked multiple times, or %q already set"
+
+type ParseError struct {
+	Message string
+	Line    int // 1-based line number
+	Offset  int // 0-based byte offset from start of input
+}
+
+func (p *ParseError) Error() string {
+	if p.Line == 1 {
+		// show offset only for first line
+		return fmt.Sprintf("line 1.%d: %v", p.Offset, p.Message)
+	}
+	return fmt.Sprintf("line %d: %v", p.Line, p.Message)
+}
+
+type token struct {
+	value    string
+	err      *ParseError
+	line     int    // line number
+	offset   int    // byte number from start of input, not start of line
+	unquoted string // the unquoted version of value, if it was a quoted string
+}
+
+func (t *token) String() string {
+	if t.err == nil {
+		return fmt.Sprintf("%q (line=%d, offset=%d)", t.value, t.line, t.offset)
+	}
+	return fmt.Sprintf("parse error: %v", t.err)
+}
+
+type textParser struct {
+	s            string // remaining input
+	done         bool   // whether the parsing is finished (success or error)
+	backed       bool   // whether back() was called
+	offset, line int
+	cur          token
+}
+
+func newTextParser(s string) *textParser {
+	p := new(textParser)
+	p.s = s
+	p.line = 1
+	p.cur.line = 1
+	return p
+}
+
+func (p *textParser) errorf(format string, a ...interface{}) *ParseError {
+	pe := &ParseError{fmt.Sprintf(format, a...), p.cur.line, p.cur.offset}
+	p.cur.err = pe
+	p.done = true
+	return pe
+}
+
+// Numbers and identifiers are matched by [-+._A-Za-z0-9]
+func isIdentOrNumberChar(c byte) bool {
+	switch {
+	case 'A' <= c && c <= 'Z', 'a' <= c && c <= 'z':
+		return true
+	case '0' <= c && c <= '9':
+		return true
+	}
+	switch c {
+	case '-', '+', '.', '_':
+		return true
+	}
+	return false
+}
+
+func isWhitespace(c byte) bool {
+	switch c {
+	case ' ', '\t', '\n', '\r':
+		return true
+	}
+	return false
+}
+
+func isQuote(c byte) bool {
+	switch c {
+	case '"', '\'':
+		return true
+	}
+	return false
+}
+
+func (p *textParser) skipWhitespace() {
+	i := 0
+	for i < len(p.s) && (isWhitespace(p.s[i]) || p.s[i] == '#') {
+		if p.s[i] == '#' {
+			// comment; skip to end of line or input
+			for i < len(p.s) && p.s[i] != '\n' {
+				i++
+			}
+			if i == len(p.s) {
+				break
+			}
+		}
+		if p.s[i] == '\n' {
+			p.line++
+		}
+		i++
+	}
+	p.offset += i
+	p.s = p.s[i:len(p.s)]
+	if len(p.s) == 0 {
+		p.done = true
+	}
+}
+
+func (p *textParser) advance() {
+	// Skip whitespace
+	p.skipWhitespace()
+	if p.done {
+		return
+	}
+
+	// Start of non-whitespace
+	p.cur.err = nil
+	p.cur.offset, p.cur.line = p.offset, p.line
+	p.cur.unquoted = ""
+	switch p.s[0] {
+	case '<', '>', '{', '}', ':', '[', ']', ';', ',', '/':
+		// Single symbol
+		p.cur.value, p.s = p.s[0:1], p.s[1:len(p.s)]
+	case '"', '\'':
+		// Quoted string
+		i := 1
+		for i < len(p.s) && p.s[i] != p.s[0] && p.s[i] != '\n' {
+			if p.s[i] == '\\' && i+1 < len(p.s) {
+				// skip escaped char
+				i++
+			}
+			i++
+		}
+		if i >= len(p.s) || p.s[i] != p.s[0] {
+			p.errorf("unmatched quote")
+			return
+		}
+		unq, err := unquoteC(p.s[1:i], rune(p.s[0]))
+		if err != nil {
+			p.errorf("invalid quoted string %s: %v", p.s[0:i+1], err)
+			return
+		}
+		p.cur.value, p.s = p.s[0:i+1], p.s[i+1:len(p.s)]
+		p.cur.unquoted = unq
+	default:
+		i := 0
+		for i < len(p.s) && isIdentOrNumberChar(p.s[i]) {
+			i++
+		}
+		if i == 0 {
+			p.errorf("unexpected byte %#x", p.s[0])
+			return
+		}
+		p.cur.value, p.s = p.s[0:i], p.s[i:len(p.s)]
+	}
+	p.offset += len(p.cur.value)
+}
+
+var (
+	errBadUTF8 = errors.New("proto: bad UTF-8")
+	errBadHex  = errors.New("proto: bad hexadecimal")
+)
+
+func unquoteC(s string, quote rune) (string, error) {
+	// This is based on C++'s tokenizer.cc.
+	// Despite its name, this is *not* parsing C syntax.
+	// For instance, "\0" is an invalid quoted string.
+
+	// Avoid allocation in trivial cases.
+	simple := true
+	for _, r := range s {
+		if r == '\\' || r == quote {
+			simple = false
+			break
+		}
+	}
+	if simple {
+		return s, nil
+	}
+
+	buf := make([]byte, 0, 3*len(s)/2)
+	for len(s) > 0 {
+		r, n := utf8.DecodeRuneInString(s)
+		if r == utf8.RuneError && n == 1 {
+			return "", errBadUTF8
+		}
+		s = s[n:]
+		if r != '\\' {
+			if r < utf8.RuneSelf {
+				buf = append(buf, byte(r))
+			} else {
+				buf = append(buf, string(r)...)
+			}
+			continue
+		}
+
+		ch, tail, err := unescape(s)
+		if err != nil {
+			return "", err
+		}
+		buf = append(buf, ch...)
+		s = tail
+	}
+	return string(buf), nil
+}
+
+func unescape(s string) (ch string, tail string, err error) {
+	r, n := utf8.DecodeRuneInString(s)
+	if r == utf8.RuneError && n == 1 {
+		return "", "", errBadUTF8
+	}
+	s = s[n:]
+	switch r {
+	case 'a':
+		return "\a", s, nil
+	case 'b':
+		return "\b", s, nil
+	case 'f':
+		return "\f", s, nil
+	case 'n':
+		return "\n", s, nil
+	case 'r':
+		return "\r", s, nil
+	case 't':
+		return "\t", s, nil
+	case 'v':
+		return "\v", s, nil
+	case '?':
+		return "?", s, nil // trigraph workaround
+	case '\'', '"', '\\':
+		return string(r), s, nil
+	case '0', '1', '2', '3', '4', '5', '6', '7', 'x', 'X':
+		if len(s) < 2 {
+			return "", "", fmt.Errorf(`\%c requires 2 following digits`, r)
+		}
+		base := 8
+		ss := s[:2]
+		s = s[2:]
+		if r == 'x' || r == 'X' {
+			base = 16
+		} else {
+			ss = string(r) + ss
+		}
+		i, err := strconv.ParseUint(ss, base, 8)
+		if err != nil {
+			return "", "", err
+		}
+		return string([]byte{byte(i)}), s, nil
+	case 'u', 'U':
+		n := 4
+		if r == 'U' {
+			n = 8
+		}
+		if len(s) < n {
+			return "", "", fmt.Errorf(`\%c requires %d digits`, r, n)
+		}
+
+		bs := make([]byte, n/2)
+		for i := 0; i < n; i += 2 {
+			a, ok1 := unhex(s[i])
+			b, ok2 := unhex(s[i+1])
+			if !ok1 || !ok2 {
+				return "", "", errBadHex
+			}
+			bs[i/2] = a<<4 | b
+		}
+		s = s[n:]
+		return string(bs), s, nil
+	}
+	return "", "", fmt.Errorf(`unknown escape \%c`, r)
+}
+
+// Adapted from src/pkg/strconv/quote.go.
+func unhex(b byte) (v byte, ok bool) {
+	switch {
+	case '0' <= b && b <= '9':
+		return b - '0', true
+	case 'a' <= b && b <= 'f':
+		return b - 'a' + 10, true
+	case 'A' <= b && b <= 'F':
+		return b - 'A' + 10, true
+	}
+	return 0, false
+}
+
+// Back off the parser by one token. Can only be done between calls to next().
+// It makes the next advance() a no-op.
+func (p *textParser) back() { p.backed = true }
+
+// Advances the parser and returns the new current token.
+func (p *textParser) next() *token {
+	if p.backed || p.done {
+		p.backed = false
+		return &p.cur
+	}
+	p.advance()
+	if p.done {
+		p.cur.value = ""
+	} else if len(p.cur.value) > 0 && isQuote(p.cur.value[0]) {
+		// Look for multiple quoted strings separated by whitespace,
+		// and concatenate them.
+		cat := p.cur
+		for {
+			p.skipWhitespace()
+			if p.done || !isQuote(p.s[0]) {
+				break
+			}
+			p.advance()
+			if p.cur.err != nil {
+				return &p.cur
+			}
+			cat.value += " " + p.cur.value
+			cat.unquoted += p.cur.unquoted
+		}
+		p.done = false // parser may have seen EOF, but we want to return cat
+		p.cur = cat
+	}
+	return &p.cur
+}
+
+func (p *textParser) consumeToken(s string) error {
+	tok := p.next()
+	if tok.err != nil {
+		return tok.err
+	}
+	if tok.value != s {
+		p.back()
+		return p.errorf("expected %q, found %q", s, tok.value)
+	}
+	return nil
+}
+
+// Return a RequiredNotSetError indicating which required field was not set.
+func (p *textParser) missingRequiredFieldError(sv reflect.Value) *RequiredNotSetError {
+	st := sv.Type()
+	sprops := GetProperties(st)
+	for i := 0; i < st.NumField(); i++ {
+		if !isNil(sv.Field(i)) {
+			continue
+		}
+
+		props := sprops.Prop[i]
+		if props.Required {
+			return &RequiredNotSetError{fmt.Sprintf("%v.%v", st, props.OrigName)}
+		}
+	}
+	return &RequiredNotSetError{fmt.Sprintf("%v.<unknown field name>", st)} // should not happen
+}
+
+// Returns the index in the struct for the named field, as well as the parsed tag properties.
+func structFieldByName(sprops *StructProperties, name string) (int, *Properties, bool) {
+	i, ok := sprops.decoderOrigNames[name]
+	if ok {
+		return i, sprops.Prop[i], true
+	}
+	return -1, nil, false
+}
+
+// Consume a ':' from the input stream (if the next token is a colon),
+// returning an error if a colon is needed but not present.
+func (p *textParser) checkForColon(props *Properties, typ reflect.Type) *ParseError {
+	tok := p.next()
+	if tok.err != nil {
+		return tok.err
+	}
+	if tok.value != ":" {
+		// Colon is optional when the field is a group or message.
+		needColon := true
+		switch props.Wire {
+		case "group":
+			needColon = false
+		case "bytes":
+			// A "bytes" field is either a message, a string, or a repeated field;
+			// those three become *T, *string and []T respectively, so we can check for
+			// this field being a pointer to a non-string.
+			if typ.Kind() == reflect.Ptr {
+				// *T or *string
+				if typ.Elem().Kind() == reflect.String {
+					break
+				}
+			} else if typ.Kind() == reflect.Slice {
+				// []T or []*T
+				if typ.Elem().Kind() != reflect.Ptr {
+					break
+				}
+			} else if typ.Kind() == reflect.String {
+				// The proto3 exception is for a string field,
+				// which requires a colon.
+				break
+			}
+			needColon = false
+		}
+		if needColon {
+			return p.errorf("expected ':', found %q", tok.value)
+		}
+		p.back()
+	}
+	return nil
+}
+
+func (p *textParser) readStruct(sv reflect.Value, terminator string) error {
+	st := sv.Type()
+	sprops := GetProperties(st)
+	reqCount := sprops.reqCount
+	var reqFieldErr error
+	fieldSet := make(map[string]bool)
+	// A struct is a sequence of "name: value", terminated by one of
+	// '>' or '}', or the end of the input.  A name may also be
+	// "[extension]" or "[type/url]".
+	//
+	// The whole struct can also be an expanded Any message, like:
+	// [type/url] < ... struct contents ... >
+	for {
+		tok := p.next()
+		if tok.err != nil {
+			return tok.err
+		}
+		if tok.value == terminator {
+			break
+		}
+		if tok.value == "[" {
+			// Looks like an extension or an Any.
+			//
+			// TODO: Check whether we need to handle
+			// namespace rooted names (e.g. ".something.Foo").
+			extName, err := p.consumeExtName()
+			if err != nil {
+				return err
+			}
+
+			if s := strings.LastIndex(extName, "/"); s >= 0 {
+				// If it contains a slash, it's an Any type URL.
+				messageName := extName[s+1:]
+				mt := MessageType(messageName)
+				if mt == nil {
+					return p.errorf("unrecognized message %q in google.protobuf.Any", messageName)
+				}
+				tok = p.next()
+				if tok.err != nil {
+					return tok.err
+				}
+				// consume an optional colon
+				if tok.value == ":" {
+					tok = p.next()
+					if tok.err != nil {
+						return tok.err
+					}
+				}
+				var terminator string
+				switch tok.value {
+				case "<":
+					terminator = ">"
+				case "{":
+					terminator = "}"
+				default:
+					return p.errorf("expected '{' or '<', found %q", tok.value)
+				}
+				v := reflect.New(mt.Elem())
+				if pe := p.readStruct(v.Elem(), terminator); pe != nil {
+					return pe
+				}
+				b, err := Marshal(v.Interface().(Message))
+				if err != nil {
+					return p.errorf("failed to marshal message of type %q: %v", messageName, err)
+				}
+				if fieldSet["type_url"] {
+					return p.errorf(anyRepeatedlyUnpacked, "type_url")
+				}
+				if fieldSet["value"] {
+					return p.errorf(anyRepeatedlyUnpacked, "value")
+				}
+				sv.FieldByName("TypeUrl").SetString(extName)
+				sv.FieldByName("Value").SetBytes(b)
+				fieldSet["type_url"] = true
+				fieldSet["value"] = true
+				continue
+			}
+
+			var desc *ExtensionDesc
+			// This could be faster, but it's functional.
+			// TODO: Do something smarter than a linear scan.
+			for _, d := range RegisteredExtensions(reflect.New(st).Interface().(Message)) {
+				if d.Name == extName {
+					desc = d
+					break
+				}
+			}
+			if desc == nil {
+				return p.errorf("unrecognized extension %q", extName)
+			}
+
+			props := &Properties{}
+			props.Parse(desc.Tag)
+
+			typ := reflect.TypeOf(desc.ExtensionType)
+			if err := p.checkForColon(props, typ); err != nil {
+				return err
+			}
+
+			rep := desc.repeated()
+
+			// Read the extension structure, and set it in
+			// the value we're constructing.
+			var ext reflect.Value
+			if !rep {
+				ext = reflect.New(typ).Elem()
+			} else {
+				ext = reflect.New(typ.Elem()).Elem()
+			}
+			if err := p.readAny(ext, props); err != nil {
+				if _, ok := err.(*RequiredNotSetError); !ok {
+					return err
+				}
+				reqFieldErr = err
+			}
+			ep := sv.Addr().Interface().(Message)
+			if !rep {
+				SetExtension(ep, desc, ext.Interface())
+			} else {
+				old, err := GetExtension(ep, desc)
+				var sl reflect.Value
+				if err == nil {
+					sl = reflect.ValueOf(old) // existing slice
+				} else {
+					sl = reflect.MakeSlice(typ, 0, 1)
+				}
+				sl = reflect.Append(sl, ext)
+				SetExtension(ep, desc, sl.Interface())
+			}
+			if err := p.consumeOptionalSeparator(); err != nil {
+				return err
+			}
+			continue
+		}
+
+		// This is a normal, non-extension field.
+		name := tok.value
+		var dst reflect.Value
+		fi, props, ok := structFieldByName(sprops, name)
+		if ok {
+			dst = sv.Field(fi)
+		} else if oop, ok := sprops.OneofTypes[name]; ok {
+			// It is a oneof.
+			props = oop.Prop
+			nv := reflect.New(oop.Type.Elem())
+			dst = nv.Elem().Field(0)
+			field := sv.Field(oop.Field)
+			if !field.IsNil() {
+				return p.errorf("field '%s' would overwrite already parsed oneof '%s'", name, sv.Type().Field(oop.Field).Name)
+			}
+			field.Set(nv)
+		}
+		if !dst.IsValid() {
+			return p.errorf("unknown field name %q in %v", name, st)
+		}
+
+		if dst.Kind() == reflect.Map {
+			// Consume any colon.
+			if err := p.checkForColon(props, dst.Type()); err != nil {
+				return err
+			}
+
+			// Construct the map if it doesn't already exist.
+			if dst.IsNil() {
+				dst.Set(reflect.MakeMap(dst.Type()))
+			}
+			key := reflect.New(dst.Type().Key()).Elem()
+			val := reflect.New(dst.Type().Elem()).Elem()
+
+			// The map entry should be this sequence of tokens:
+			//	< key : KEY value : VALUE >
+			// However, implementations may omit key or value, and technically
+			// we should support them in any order.  See b/28924776 for a time
+			// this went wrong.
+
+			tok := p.next()
+			var terminator string
+			switch tok.value {
+			case "<":
+				terminator = ">"
+			case "{":
+				terminator = "}"
+			default:
+				return p.errorf("expected '{' or '<', found %q", tok.value)
+			}
+			for {
+				tok := p.next()
+				if tok.err != nil {
+					return tok.err
+				}
+				if tok.value == terminator {
+					break
+				}
+				switch tok.value {
+				case "key":
+					if err := p.consumeToken(":"); err != nil {
+						return err
+					}
+					if err := p.readAny(key, props.mkeyprop); err != nil {
+						return err
+					}
+					if err := p.consumeOptionalSeparator(); err != nil {
+						return err
+					}
+				case "value":
+					if err := p.checkForColon(props.mvalprop, dst.Type().Elem()); err != nil {
+						return err
+					}
+					if err := p.readAny(val, props.mvalprop); err != nil {
+						return err
+					}
+					if err := p.consumeOptionalSeparator(); err != nil {
+						return err
+					}
+				default:
+					p.back()
+					return p.errorf(`expected "key", "value", or %q, found %q`, terminator, tok.value)
+				}
+			}
+
+			dst.SetMapIndex(key, val)
+			continue
+		}
+
+		// Check that it's not already set if it's not a repeated field.
+		if !props.Repeated && fieldSet[name] {
+			return p.errorf("non-repeated field %q was repeated", name)
+		}
+
+		if err := p.checkForColon(props, dst.Type()); err != nil {
+			return err
+		}
+
+		// Parse into the field.
+		fieldSet[name] = true
+		if err := p.readAny(dst, props); err != nil {
+			if _, ok := err.(*RequiredNotSetError); !ok {
+				return err
+			}
+			reqFieldErr = err
+		}
+		if props.Required {
+			reqCount--
+		}
+
+		if err := p.consumeOptionalSeparator(); err != nil {
+			return err
+		}
+
+	}
+
+	if reqCount > 0 {
+		return p.missingRequiredFieldError(sv)
+	}
+	return reqFieldErr
+}
+
+// consumeExtName consumes extension name or expanded Any type URL and the
+// following ']'. It returns the name or URL consumed.
+func (p *textParser) consumeExtName() (string, error) {
+	tok := p.next()
+	if tok.err != nil {
+		return "", tok.err
+	}
+
+	// If extension name or type url is quoted, it's a single token.
+	if len(tok.value) > 2 && isQuote(tok.value[0]) && tok.value[len(tok.value)-1] == tok.value[0] {
+		name, err := unquoteC(tok.value[1:len(tok.value)-1], rune(tok.value[0]))
+		if err != nil {
+			return "", err
+		}
+		return name, p.consumeToken("]")
+	}
+
+	// Consume everything up to "]"
+	var parts []string
+	for tok.value != "]" {
+		parts = append(parts, tok.value)
+		tok = p.next()
+		if tok.err != nil {
+			return "", p.errorf("unrecognized type_url or extension name: %s", tok.err)
+		}
+	}
+	return strings.Join(parts, ""), nil
+}
+
+// consumeOptionalSeparator consumes an optional semicolon or comma.
+// It is used in readStruct to provide backward compatibility.
+func (p *textParser) consumeOptionalSeparator() error {
+	tok := p.next()
+	if tok.err != nil {
+		return tok.err
+	}
+	if tok.value != ";" && tok.value != "," {
+		p.back()
+	}
+	return nil
+}
+
+func (p *textParser) readAny(v reflect.Value, props *Properties) error {
+	tok := p.next()
+	if tok.err != nil {
+		return tok.err
+	}
+	if tok.value == "" {
+		return p.errorf("unexpected EOF")
+	}
+
+	switch fv := v; fv.Kind() {
+	case reflect.Slice:
+		at := v.Type()
+		if at.Elem().Kind() == reflect.Uint8 {
+			// Special case for []byte
+			if tok.value[0] != '"' && tok.value[0] != '\'' {
+				// Deliberately written out here, as the error after
+				// this switch statement would write "invalid []byte: ...",
+				// which is not as user-friendly.
+				return p.errorf("invalid string: %v", tok.value)
+			}
+			bytes := []byte(tok.unquoted)
+			fv.Set(reflect.ValueOf(bytes))
+			return nil
+		}
+		// Repeated field.
+		if tok.value == "[" {
+			// Repeated field with list notation, like [1,2,3].
+			for {
+				fv.Set(reflect.Append(fv, reflect.New(at.Elem()).Elem()))
+				err := p.readAny(fv.Index(fv.Len()-1), props)
+				if err != nil {
+					return err
+				}
+				tok := p.next()
+				if tok.err != nil {
+					return tok.err
+				}
+				if tok.value == "]" {
+					break
+				}
+				if tok.value != "," {
+					return p.errorf("Expected ']' or ',' found %q", tok.value)
+				}
+			}
+			return nil
+		}
+		// One value of the repeated field.
+		p.back()
+		fv.Set(reflect.Append(fv, reflect.New(at.Elem()).Elem()))
+		return p.readAny(fv.Index(fv.Len()-1), props)
+	case reflect.Bool:
+		// true/1/t/True or false/f/0/False.
+		switch tok.value {
+		case "true", "1", "t", "True":
+			fv.SetBool(true)
+			return nil
+		case "false", "0", "f", "False":
+			fv.SetBool(false)
+			return nil
+		}
+	case reflect.Float32, reflect.Float64:
+		v := tok.value
+		// Ignore 'f' for compatibility with output generated by C++, but don't
+		// remove 'f' when the value is "-inf" or "inf".
+		if strings.HasSuffix(v, "f") && tok.value != "-inf" && tok.value != "inf" {
+			v = v[:len(v)-1]
+		}
+		if f, err := strconv.ParseFloat(v, fv.Type().Bits()); err == nil {
+			fv.SetFloat(f)
+			return nil
+		}
+	case reflect.Int32:
+		if x, err := strconv.ParseInt(tok.value, 0, 32); err == nil {
+			fv.SetInt(x)
+			return nil
+		}
+
+		if len(props.Enum) == 0 {
+			break
+		}
+		m, ok := enumValueMaps[props.Enum]
+		if !ok {
+			break
+		}
+		x, ok := m[tok.value]
+		if !ok {
+			break
+		}
+		fv.SetInt(int64(x))
+		return nil
+	case reflect.Int64:
+		if x, err := strconv.ParseInt(tok.value, 0, 64); err == nil {
+			fv.SetInt(x)
+			return nil
+		}
+
+	case reflect.Ptr:
+		// A basic field (indirected through pointer), or a repeated message/group
+		p.back()
+		fv.Set(reflect.New(fv.Type().Elem()))
+		return p.readAny(fv.Elem(), props)
+	case reflect.String:
+		if tok.value[0] == '"' || tok.value[0] == '\'' {
+			fv.SetString(tok.unquoted)
+			return nil
+		}
+	case reflect.Struct:
+		var terminator string
+		switch tok.value {
+		case "{":
+			terminator = "}"
+		case "<":
+			terminator = ">"
+		default:
+			return p.errorf("expected '{' or '<', found %q", tok.value)
+		}
+		// TODO: Handle nested messages which implement encoding.TextUnmarshaler.
+		return p.readStruct(fv, terminator)
+	case reflect.Uint32:
+		if x, err := strconv.ParseUint(tok.value, 0, 32); err == nil {
+			fv.SetUint(uint64(x))
+			return nil
+		}
+	case reflect.Uint64:
+		if x, err := strconv.ParseUint(tok.value, 0, 64); err == nil {
+			fv.SetUint(x)
+			return nil
+		}
+	}
+	return p.errorf("invalid %v: %v", v.Type(), tok.value)
+}
+
+// UnmarshalText reads a protocol buffer in Text format. UnmarshalText resets pb
+// before starting to unmarshal, so any existing data in pb is always removed.
+// If a required field is not set and no other error occurs,
+// UnmarshalText returns *RequiredNotSetError.
+func UnmarshalText(s string, pb Message) error {
+	if um, ok := pb.(encoding.TextUnmarshaler); ok {
+		err := um.UnmarshalText([]byte(s))
+		return err
+	}
+	pb.Reset()
+	v := reflect.ValueOf(pb)
+	if pe := newTextParser(s).readStruct(v.Elem(), ""); pe != nil {
+		return pe
+	}
+	return nil
+}