messageset.go raw

   1  // Copyright 2019 The Go Authors. All rights reserved.
   2  // Use of this source code is governed by a BSD-style
   3  // license that can be found in the LICENSE file.
   4  
   5  package proto
   6  
   7  import (
   8  	"google.golang.org/protobuf/encoding/protowire"
   9  	"google.golang.org/protobuf/internal/encoding/messageset"
  10  	"google.golang.org/protobuf/internal/errors"
  11  	"google.golang.org/protobuf/internal/flags"
  12  	"google.golang.org/protobuf/internal/order"
  13  	"google.golang.org/protobuf/reflect/protoreflect"
  14  	"google.golang.org/protobuf/reflect/protoregistry"
  15  )
  16  
  17  func (o MarshalOptions) sizeMessageSet(m protoreflect.Message) (size int) {
  18  	m.Range(func(fd protoreflect.FieldDescriptor, v protoreflect.Value) bool {
  19  		size += messageset.SizeField(fd.Number())
  20  		size += protowire.SizeTag(messageset.FieldMessage)
  21  		size += protowire.SizeBytes(o.size(v.Message()))
  22  		return true
  23  	})
  24  	size += messageset.SizeUnknown(m.GetUnknown())
  25  	return size
  26  }
  27  
  28  func (o MarshalOptions) marshalMessageSet(b []byte, m protoreflect.Message) ([]byte, error) {
  29  	if !flags.ProtoLegacy {
  30  		return b, errors.New("no support for message_set_wire_format")
  31  	}
  32  	fieldOrder := order.AnyFieldOrder
  33  	if o.Deterministic {
  34  		fieldOrder = order.NumberFieldOrder
  35  	}
  36  	var err error
  37  	order.RangeFields(m, fieldOrder, func(fd protoreflect.FieldDescriptor, v protoreflect.Value) bool {
  38  		b, err = o.marshalMessageSetField(b, fd, v)
  39  		return err == nil
  40  	})
  41  	if err != nil {
  42  		return b, err
  43  	}
  44  	return messageset.AppendUnknown(b, m.GetUnknown())
  45  }
  46  
  47  func (o MarshalOptions) marshalMessageSetField(b []byte, fd protoreflect.FieldDescriptor, value protoreflect.Value) ([]byte, error) {
  48  	b = messageset.AppendFieldStart(b, fd.Number())
  49  	b = protowire.AppendTag(b, messageset.FieldMessage, protowire.BytesType)
  50  	calculatedSize := o.Size(value.Message().Interface())
  51  	b = protowire.AppendVarint(b, uint64(calculatedSize))
  52  	before := len(b)
  53  	b, err := o.marshalMessage(b, value.Message())
  54  	if err != nil {
  55  		return b, err
  56  	}
  57  	if measuredSize := len(b) - before; calculatedSize != measuredSize {
  58  		return nil, errors.MismatchedSizeCalculation(calculatedSize, measuredSize)
  59  	}
  60  	b = messageset.AppendFieldEnd(b)
  61  	return b, nil
  62  }
  63  
  64  func (o UnmarshalOptions) unmarshalMessageSet(b []byte, m protoreflect.Message) error {
  65  	if !flags.ProtoLegacy {
  66  		return errors.New("no support for message_set_wire_format")
  67  	}
  68  	return messageset.Unmarshal(b, false, func(num protowire.Number, v []byte) error {
  69  		err := o.unmarshalMessageSetField(m, num, v)
  70  		if err == errUnknown {
  71  			unknown := m.GetUnknown()
  72  			unknown = protowire.AppendTag(unknown, num, protowire.BytesType)
  73  			unknown = protowire.AppendBytes(unknown, v)
  74  			m.SetUnknown(unknown)
  75  			return nil
  76  		}
  77  		return err
  78  	})
  79  }
  80  
  81  func (o UnmarshalOptions) unmarshalMessageSetField(m protoreflect.Message, num protowire.Number, v []byte) error {
  82  	md := m.Descriptor()
  83  	if !md.ExtensionRanges().Has(num) {
  84  		return errUnknown
  85  	}
  86  	xt, err := o.Resolver.FindExtensionByNumber(md.FullName(), num)
  87  	if err == protoregistry.NotFound {
  88  		return errUnknown
  89  	}
  90  	if err != nil {
  91  		return errors.New("%v: unable to resolve extension %v: %v", md.FullName(), num, err)
  92  	}
  93  	xd := xt.TypeDescriptor()
  94  	if err := o.unmarshalMessage(v, m.Mutable(xd).Message()); err != nil {
  95  		return err
  96  	}
  97  	return nil
  98  }
  99