source: code/trunk/vendor/google.golang.org/protobuf/proto/messageset.go@ 822

// Copyright 2019 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

package proto

import (
        "google.golang.org/protobuf/encoding/protowire"
        "google.golang.org/protobuf/internal/encoding/messageset"
        "google.golang.org/protobuf/internal/errors"
        "google.golang.org/protobuf/internal/flags"
        "google.golang.org/protobuf/internal/order"
        "google.golang.org/protobuf/reflect/protoreflect"
        "google.golang.org/protobuf/reflect/protoregistry"
)

func (o MarshalOptions) sizeMessageSet(m protoreflect.Message) (size int) {
        m.Range(func(fd protoreflect.FieldDescriptor, v protoreflect.Value) bool {
                size += messageset.SizeField(fd.Number())
                size += protowire.SizeTag(messageset.FieldMessage)
                size += protowire.SizeBytes(o.size(v.Message()))
                return true
        })
        size += messageset.SizeUnknown(m.GetUnknown())
        return size
}

func (o MarshalOptions) marshalMessageSet(b []byte, m protoreflect.Message) ([]byte, error) {
        if !flags.ProtoLegacy {
                return b, errors.New("no support for message_set_wire_format")
        }
        fieldOrder := order.AnyFieldOrder
        if o.Deterministic {
                fieldOrder = order.NumberFieldOrder
        }
        var err error
        order.RangeFields(m, fieldOrder, func(fd protoreflect.FieldDescriptor, v protoreflect.Value) bool {
                b, err = o.marshalMessageSetField(b, fd, v)
                return err == nil
        })
        if err != nil {
                return b, err
        }
        return messageset.AppendUnknown(b, m.GetUnknown())
}

func (o MarshalOptions) marshalMessageSetField(b []byte, fd protoreflect.FieldDescriptor, value protoreflect.Value) ([]byte, error) {
        b = messageset.AppendFieldStart(b, fd.Number())
        b = protowire.AppendTag(b, messageset.FieldMessage, protowire.BytesType)
        b = protowire.AppendVarint(b, uint64(o.Size(value.Message().Interface())))
        b, err := o.marshalMessage(b, value.Message())
        if err != nil {
                return b, err
        }
        b = messageset.AppendFieldEnd(b)
        return b, nil
}

func (o UnmarshalOptions) unmarshalMessageSet(b []byte, m protoreflect.Message) error {
        if !flags.ProtoLegacy {
                return errors.New("no support for message_set_wire_format")
        }
        return messageset.Unmarshal(b, false, func(num protowire.Number, v []byte) error {
                err := o.unmarshalMessageSetField(m, num, v)
                if err == errUnknown {
                        unknown := m.GetUnknown()
                        unknown = protowire.AppendTag(unknown, num, protowire.BytesType)
                        unknown = protowire.AppendBytes(unknown, v)
                        m.SetUnknown(unknown)
                        return nil
                }
                return err
        })
}

func (o UnmarshalOptions) unmarshalMessageSetField(m protoreflect.Message, num protowire.Number, v []byte) error {
        md := m.Descriptor()
        if !md.ExtensionRanges().Has(num) {
                return errUnknown
        }
        xt, err := o.Resolver.FindExtensionByNumber(md.FullName(), num)
        if err == protoregistry.NotFound {
                return errUnknown
        }
        if err != nil {
                return errors.New("%v: unable to resolve extension %v: %v", md.FullName(), num, err)
        }
        xd := xt.TypeDescriptor()
        if err := o.unmarshalMessage(v, m.Mutable(xd).Message()); err != nil {
                return err
        }
        return nil
}