mirror/protobuf-go
1
0
Fork 0
mirror of https://github.com/protocolbuffers/protobuf-go.git synced 2025-01-04 02:38:50 +00:00
Code Issues Packages Projects Releases Wiki Activity

internal/filedesc: avoid deep-copying the options

Browse Source 
The protoreflect.Descriptor.Options method is currently documented as
returning a reference to the options, where the user must not mutate
the returned message. This changes internal/filedesc to avoid returning
a copy of the options by caching the first unmarshal.

See golang/protobuf#877

Change-Id: I15701d33fbda7535b21b2add72628b02992c373f
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/185197
Reviewed-by: Benny Siegert <bsiegert@gmail.com>
This commit is contained in:
Joe Tsai 2019-07-06 18:08:55 -07:00
parent 93fd968b71
commit 8a4c3d18b1
2 changed files with 13 additions and 10 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

21
internal/filedesc/desc_lazy.go
View File

@ -6,6 +6,7 @@ package filedesc
import ( import (
"reflect" "reflect"
"sync"
"google.golang.org/protobuf/internal/descopts" "google.golang.org/protobuf/internal/descopts"
"google.golang.org/protobuf/internal/encoding/wire" "google.golang.org/protobuf/internal/encoding/wire"
@ -675,14 +676,18 @@ func (db *DescBuilder) optionsUnmarshaler(p pref.ProtoMessage, b []byte) func()
if b == nil { if b == nil {
return nil return nil
} }
var opts pref.ProtoMessage
var once sync.Once
return func() pref.ProtoMessage { return func() pref.ProtoMessage {
p := reflect.New(reflect.TypeOf(p).Elem()).Interface().(pref.ProtoMessage) once.Do(func() {
if err := (proto.UnmarshalOptions{ opts = reflect.New(reflect.TypeOf(p).Elem()).Interface().(pref.ProtoMessage)
AllowPartial: true, if err := (proto.UnmarshalOptions{
Resolver: db.TypeResolver, AllowPartial: true,
}).Unmarshal(b, p); err != nil { Resolver: db.TypeResolver,
panic(err) }).Unmarshal(b, opts); err != nil {
} panic(err)
return p }
})
return opts
} }
} }

2
reflect/protoreflect/type.go
View File

@ -85,8 +85,6 @@ type Descriptor interface {
// For FileDescriptor, the Path and Package are also valid. // For FileDescriptor, the Path and Package are also valid.
IsPlaceholder() bool IsPlaceholder() bool
// TODO: Decide memory ownership of Options.
// Options returns the descriptor options. The caller must not modify // Options returns the descriptor options. The caller must not modify
// the returned value. // the returned value.
// //