protobuf-go/proto/size.go
Damien Neil 302cb325fb proto: support message_set_wire_format
MessageSets are a deprecated proto1 feature, long since superseded by
extensions. Add disabled-by-default support behind flags.Proto1Legacy.

Change-Id: I7d3ace07f3b0efd59673034f3dc633b908345a88
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/185538
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
2019-07-15 19:32:30 +00:00

78 lines
2.2 KiB
Go

// 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/internal/encoding/messageset"
"google.golang.org/protobuf/internal/encoding/wire"
"google.golang.org/protobuf/reflect/protoreflect"
"google.golang.org/protobuf/runtime/protoiface"
)
// Size returns the size in bytes of the wire-format encoding of m.
func Size(m Message) int {
return MarshalOptions{}.Size(m)
}
// Size returns the size in bytes of the wire-format encoding of m.
func (o MarshalOptions) Size(m Message) int {
return sizeMessage(m.ProtoReflect())
}
func sizeMessage(m protoreflect.Message) (size int) {
if methods := protoMethods(m); methods != nil && methods.Size != nil {
return methods.Size(m, protoiface.MarshalOptions{})
}
return sizeMessageSlow(m)
}
func sizeMessageSlow(m protoreflect.Message) (size int) {
if messageset.IsMessageSet(m.Descriptor()) {
return sizeMessageSet(m)
}
m.Range(func(fd protoreflect.FieldDescriptor, v protoreflect.Value) bool {
size += sizeField(fd, v)
return true
})
size += len(m.GetUnknown())
return size
}
func sizeField(fd protoreflect.FieldDescriptor, value protoreflect.Value) (size int) {
num := fd.Number()
switch {
case fd.IsList():
return sizeList(num, fd, value.List())
case fd.IsMap():
return sizeMap(num, fd, value.Map())
default:
return wire.SizeTag(num) + sizeSingular(num, fd.Kind(), value)
}
}
func sizeList(num wire.Number, fd protoreflect.FieldDescriptor, list protoreflect.List) (size int) {
if fd.IsPacked() && list.Len() > 0 {
content := 0
for i, llen := 0, list.Len(); i < llen; i++ {
content += sizeSingular(num, fd.Kind(), list.Get(i))
}
return wire.SizeTag(num) + wire.SizeBytes(content)
}
for i, llen := 0, list.Len(); i < llen; i++ {
size += wire.SizeTag(num) + sizeSingular(num, fd.Kind(), list.Get(i))
}
return size
}
func sizeMap(num wire.Number, fd protoreflect.FieldDescriptor, mapv protoreflect.Map) (size int) {
mapv.Range(func(key protoreflect.MapKey, value protoreflect.Value) bool {
size += wire.SizeTag(num)
size += wire.SizeBytes(sizeField(fd.MapKey(), key.Value()) + sizeField(fd.MapValue(), value))
return true
})
return size
}