mirror of
https://github.com/protocolbuffers/protobuf-go.git
synced 2025-04-18 05:42:53 +00:00
e815d6a43b
Change-Id: I1344d6afca9d3348db849c2b5f387ac18b80d2ba Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/189021 Reviewed-by: Damien Neil <dneil@google.com>
517 lines
14 KiB
Go
517 lines
14 KiB
Go
// Copyright 2018 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 impl
|
|
|
|
import (
|
|
"fmt"
|
|
"math"
|
|
"reflect"
|
|
"sync"
|
|
|
|
"google.golang.org/protobuf/internal/flags"
|
|
pref "google.golang.org/protobuf/reflect/protoreflect"
|
|
preg "google.golang.org/protobuf/reflect/protoregistry"
|
|
piface "google.golang.org/protobuf/runtime/protoiface"
|
|
)
|
|
|
|
type fieldInfo struct {
|
|
fieldDesc pref.FieldDescriptor
|
|
|
|
// These fields are used for protobuf reflection support.
|
|
has func(pointer) bool
|
|
clear func(pointer)
|
|
get func(pointer) pref.Value
|
|
set func(pointer, pref.Value)
|
|
mutable func(pointer) pref.Value
|
|
newMessage func() pref.Message
|
|
}
|
|
|
|
func fieldInfoForOneof(fd pref.FieldDescriptor, fs reflect.StructField, x exporter, ot reflect.Type) fieldInfo {
|
|
ft := fs.Type
|
|
if ft.Kind() != reflect.Interface {
|
|
panic(fmt.Sprintf("invalid type: got %v, want interface kind", ft))
|
|
}
|
|
if ot.Kind() != reflect.Struct {
|
|
panic(fmt.Sprintf("invalid type: got %v, want struct kind", ot))
|
|
}
|
|
if !reflect.PtrTo(ot).Implements(ft) {
|
|
panic(fmt.Sprintf("invalid type: %v does not implement %v", ot, ft))
|
|
}
|
|
conv := NewConverter(ot.Field(0).Type, fd)
|
|
isMessage := fd.Message() != nil
|
|
var frozenEmpty pref.Value
|
|
if isMessage {
|
|
frozenEmpty = pref.ValueOf(frozenMessage{conv.New().Message()})
|
|
}
|
|
|
|
// TODO: Implement unsafe fast path?
|
|
fieldOffset := offsetOf(fs, x)
|
|
return fieldInfo{
|
|
// NOTE: The logic below intentionally assumes that oneof fields are
|
|
// well-formatted. That is, the oneof interface never contains a
|
|
// typed nil pointer to one of the wrapper structs.
|
|
|
|
fieldDesc: fd,
|
|
has: func(p pointer) bool {
|
|
if p.IsNil() {
|
|
return false
|
|
}
|
|
rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
|
|
if rv.IsNil() || rv.Elem().Type().Elem() != ot {
|
|
return false
|
|
}
|
|
return true
|
|
},
|
|
clear: func(p pointer) {
|
|
rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
|
|
if rv.IsNil() || rv.Elem().Type().Elem() != ot {
|
|
return
|
|
}
|
|
rv.Set(reflect.Zero(rv.Type()))
|
|
},
|
|
get: func(p pointer) pref.Value {
|
|
if p.IsNil() {
|
|
if frozenEmpty.IsValid() {
|
|
return frozenEmpty
|
|
}
|
|
return defaultValueOf(fd)
|
|
}
|
|
rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
|
|
if rv.IsNil() || rv.Elem().Type().Elem() != ot {
|
|
if frozenEmpty.IsValid() {
|
|
return frozenEmpty
|
|
}
|
|
return defaultValueOf(fd)
|
|
}
|
|
rv = rv.Elem().Elem().Field(0)
|
|
return conv.PBValueOf(rv)
|
|
},
|
|
set: func(p pointer, v pref.Value) {
|
|
rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
|
|
if rv.IsNil() || rv.Elem().Type().Elem() != ot {
|
|
rv.Set(reflect.New(ot))
|
|
}
|
|
rv = rv.Elem().Elem().Field(0)
|
|
rv.Set(conv.GoValueOf(v))
|
|
},
|
|
mutable: func(p pointer) pref.Value {
|
|
if !isMessage {
|
|
panic("invalid Mutable on field with non-composite type")
|
|
}
|
|
rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
|
|
if rv.IsNil() || rv.Elem().Type().Elem() != ot {
|
|
rv.Set(reflect.New(ot))
|
|
}
|
|
rv = rv.Elem().Elem().Field(0)
|
|
if rv.IsNil() {
|
|
rv.Set(conv.GoValueOf(pref.ValueOf(conv.New().Message())))
|
|
}
|
|
return conv.PBValueOf(rv)
|
|
},
|
|
newMessage: func() pref.Message {
|
|
return conv.New().Message()
|
|
},
|
|
}
|
|
}
|
|
|
|
func fieldInfoForMap(fd pref.FieldDescriptor, fs reflect.StructField, x exporter) fieldInfo {
|
|
ft := fs.Type
|
|
if ft.Kind() != reflect.Map {
|
|
panic(fmt.Sprintf("invalid type: got %v, want map kind", ft))
|
|
}
|
|
conv := NewConverter(ft, fd)
|
|
frozenEmpty := pref.ValueOf(frozenMap{conv.New().Map()})
|
|
|
|
// TODO: Implement unsafe fast path?
|
|
fieldOffset := offsetOf(fs, x)
|
|
return fieldInfo{
|
|
fieldDesc: fd,
|
|
has: func(p pointer) bool {
|
|
if p.IsNil() {
|
|
return false
|
|
}
|
|
rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
|
|
return rv.Len() > 0
|
|
},
|
|
clear: func(p pointer) {
|
|
rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
|
|
rv.Set(reflect.Zero(rv.Type()))
|
|
},
|
|
get: func(p pointer) pref.Value {
|
|
if p.IsNil() {
|
|
return frozenEmpty
|
|
}
|
|
rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
|
|
if rv.Len() == 0 {
|
|
return frozenEmpty
|
|
}
|
|
return conv.PBValueOf(rv)
|
|
},
|
|
set: func(p pointer, v pref.Value) {
|
|
rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
|
|
rv.Set(conv.GoValueOf(v))
|
|
},
|
|
mutable: func(p pointer) pref.Value {
|
|
v := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
|
|
if v.IsNil() {
|
|
v.Set(reflect.MakeMap(fs.Type))
|
|
}
|
|
return conv.PBValueOf(v)
|
|
},
|
|
}
|
|
}
|
|
|
|
func fieldInfoForList(fd pref.FieldDescriptor, fs reflect.StructField, x exporter) fieldInfo {
|
|
ft := fs.Type
|
|
if ft.Kind() != reflect.Slice {
|
|
panic(fmt.Sprintf("invalid type: got %v, want slice kind", ft))
|
|
}
|
|
conv := NewConverter(reflect.PtrTo(ft), fd)
|
|
frozenEmpty := pref.ValueOf(frozenList{conv.New().List()})
|
|
|
|
// TODO: Implement unsafe fast path?
|
|
fieldOffset := offsetOf(fs, x)
|
|
return fieldInfo{
|
|
fieldDesc: fd,
|
|
has: func(p pointer) bool {
|
|
if p.IsNil() {
|
|
return false
|
|
}
|
|
rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
|
|
return rv.Len() > 0
|
|
},
|
|
clear: func(p pointer) {
|
|
rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
|
|
rv.Set(reflect.Zero(rv.Type()))
|
|
},
|
|
get: func(p pointer) pref.Value {
|
|
if p.IsNil() {
|
|
return frozenEmpty
|
|
}
|
|
rv := p.Apply(fieldOffset).AsValueOf(fs.Type)
|
|
if rv.Elem().Len() == 0 {
|
|
return frozenEmpty
|
|
}
|
|
return conv.PBValueOf(rv)
|
|
},
|
|
set: func(p pointer, v pref.Value) {
|
|
rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
|
|
rv.Set(reflect.ValueOf(v.List().(Unwrapper).ProtoUnwrap()).Elem())
|
|
},
|
|
mutable: func(p pointer) pref.Value {
|
|
v := p.Apply(fieldOffset).AsValueOf(fs.Type)
|
|
return conv.PBValueOf(v)
|
|
},
|
|
}
|
|
}
|
|
|
|
var (
|
|
nilBytes = reflect.ValueOf([]byte(nil))
|
|
emptyBytes = reflect.ValueOf([]byte{})
|
|
)
|
|
|
|
func fieldInfoForScalar(fd pref.FieldDescriptor, fs reflect.StructField, x exporter) fieldInfo {
|
|
ft := fs.Type
|
|
nullable := fd.Syntax() == pref.Proto2
|
|
isBytes := ft.Kind() == reflect.Slice && ft.Elem().Kind() == reflect.Uint8
|
|
if nullable {
|
|
if ft.Kind() != reflect.Ptr && ft.Kind() != reflect.Slice {
|
|
panic(fmt.Sprintf("invalid type: got %v, want pointer", ft))
|
|
}
|
|
if ft.Kind() == reflect.Ptr {
|
|
ft = ft.Elem()
|
|
}
|
|
}
|
|
conv := NewConverter(ft, fd)
|
|
|
|
// TODO: Implement unsafe fast path?
|
|
fieldOffset := offsetOf(fs, x)
|
|
return fieldInfo{
|
|
fieldDesc: fd,
|
|
has: func(p pointer) bool {
|
|
if p.IsNil() {
|
|
return false
|
|
}
|
|
rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
|
|
if nullable {
|
|
return !rv.IsNil()
|
|
}
|
|
switch rv.Kind() {
|
|
case reflect.Bool:
|
|
return rv.Bool()
|
|
case reflect.Int32, reflect.Int64:
|
|
return rv.Int() != 0
|
|
case reflect.Uint32, reflect.Uint64:
|
|
return rv.Uint() != 0
|
|
case reflect.Float32, reflect.Float64:
|
|
return rv.Float() != 0 || math.Signbit(rv.Float())
|
|
case reflect.String, reflect.Slice:
|
|
return rv.Len() > 0
|
|
default:
|
|
panic(fmt.Sprintf("invalid type: %v", rv.Type())) // should never happen
|
|
}
|
|
},
|
|
clear: func(p pointer) {
|
|
rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
|
|
rv.Set(reflect.Zero(rv.Type()))
|
|
},
|
|
get: func(p pointer) pref.Value {
|
|
if p.IsNil() {
|
|
return defaultValueOf(fd)
|
|
}
|
|
rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
|
|
if nullable {
|
|
if rv.IsNil() {
|
|
return defaultValueOf(fd)
|
|
}
|
|
if rv.Kind() == reflect.Ptr {
|
|
rv = rv.Elem()
|
|
}
|
|
}
|
|
return conv.PBValueOf(rv)
|
|
},
|
|
set: func(p pointer, v pref.Value) {
|
|
rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
|
|
if nullable && rv.Kind() == reflect.Ptr {
|
|
if rv.IsNil() {
|
|
rv.Set(reflect.New(ft))
|
|
}
|
|
rv = rv.Elem()
|
|
}
|
|
rv.Set(conv.GoValueOf(v))
|
|
if isBytes && rv.Len() == 0 {
|
|
if nullable {
|
|
rv.Set(emptyBytes) // preserve presence in proto2
|
|
} else {
|
|
rv.Set(nilBytes) // do not preserve presence in proto3
|
|
}
|
|
}
|
|
},
|
|
}
|
|
}
|
|
|
|
func fieldInfoForWeakMessage(fd pref.FieldDescriptor, weakOffset offset) fieldInfo {
|
|
if !flags.Proto1Legacy {
|
|
panic("no support for proto1 weak fields")
|
|
}
|
|
|
|
var once sync.Once
|
|
var messageType pref.MessageType
|
|
var frozenEmpty pref.Value
|
|
lazyInit := func() {
|
|
once.Do(func() {
|
|
messageName := fd.Message().FullName()
|
|
messageType, _ = preg.GlobalTypes.FindMessageByName(messageName)
|
|
if messageType == nil {
|
|
panic(fmt.Sprintf("weak message %v is not linked in", messageName))
|
|
}
|
|
frozenEmpty = pref.ValueOf(frozenMessage{messageType.New()})
|
|
})
|
|
}
|
|
|
|
num := int32(fd.Number())
|
|
return fieldInfo{
|
|
fieldDesc: fd,
|
|
has: func(p pointer) bool {
|
|
if p.IsNil() {
|
|
return false
|
|
}
|
|
fs := p.Apply(weakOffset).WeakFields()
|
|
_, ok := (*fs)[num]
|
|
return ok
|
|
},
|
|
clear: func(p pointer) {
|
|
fs := p.Apply(weakOffset).WeakFields()
|
|
delete(*fs, num)
|
|
},
|
|
get: func(p pointer) pref.Value {
|
|
lazyInit()
|
|
if p.IsNil() {
|
|
return frozenEmpty
|
|
}
|
|
fs := p.Apply(weakOffset).WeakFields()
|
|
m, ok := (*fs)[num]
|
|
if !ok {
|
|
return frozenEmpty
|
|
}
|
|
return pref.ValueOf(m.(pref.ProtoMessage).ProtoReflect())
|
|
},
|
|
set: func(p pointer, v pref.Value) {
|
|
lazyInit()
|
|
m := v.Message()
|
|
if m.Descriptor() != messageType.Descriptor() {
|
|
panic("mismatching message descriptor")
|
|
}
|
|
fs := p.Apply(weakOffset).WeakFields()
|
|
if *fs == nil {
|
|
*fs = make(WeakFields)
|
|
}
|
|
(*fs)[num] = m.Interface().(piface.MessageV1)
|
|
},
|
|
mutable: func(p pointer) pref.Value {
|
|
lazyInit()
|
|
fs := p.Apply(weakOffset).WeakFields()
|
|
if *fs == nil {
|
|
*fs = make(WeakFields)
|
|
}
|
|
m, ok := (*fs)[num]
|
|
if !ok {
|
|
m = messageType.New().Interface().(piface.MessageV1)
|
|
(*fs)[num] = m
|
|
}
|
|
return pref.ValueOf(m.(pref.ProtoMessage).ProtoReflect())
|
|
},
|
|
newMessage: func() pref.Message {
|
|
lazyInit()
|
|
return messageType.New()
|
|
},
|
|
}
|
|
}
|
|
|
|
func fieldInfoForMessage(fd pref.FieldDescriptor, fs reflect.StructField, x exporter) fieldInfo {
|
|
ft := fs.Type
|
|
conv := NewConverter(ft, fd)
|
|
frozenEmpty := pref.ValueOf(frozenMessage{conv.New().Message()})
|
|
|
|
// TODO: Implement unsafe fast path?
|
|
fieldOffset := offsetOf(fs, x)
|
|
return fieldInfo{
|
|
fieldDesc: fd,
|
|
has: func(p pointer) bool {
|
|
if p.IsNil() {
|
|
return false
|
|
}
|
|
rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
|
|
return !rv.IsNil()
|
|
},
|
|
clear: func(p pointer) {
|
|
rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
|
|
rv.Set(reflect.Zero(rv.Type()))
|
|
},
|
|
get: func(p pointer) pref.Value {
|
|
if p.IsNil() {
|
|
return frozenEmpty
|
|
}
|
|
rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
|
|
if rv.IsNil() {
|
|
return frozenEmpty
|
|
}
|
|
return conv.PBValueOf(rv)
|
|
},
|
|
set: func(p pointer, v pref.Value) {
|
|
rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
|
|
rv.Set(conv.GoValueOf(v))
|
|
if rv.IsNil() {
|
|
panic("invalid nil pointer")
|
|
}
|
|
},
|
|
mutable: func(p pointer) pref.Value {
|
|
rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
|
|
if rv.IsNil() {
|
|
rv.Set(conv.GoValueOf(conv.New()))
|
|
}
|
|
return conv.PBValueOf(rv)
|
|
},
|
|
newMessage: func() pref.Message {
|
|
return conv.New().Message()
|
|
},
|
|
}
|
|
}
|
|
|
|
type oneofInfo struct {
|
|
oneofDesc pref.OneofDescriptor
|
|
which func(pointer) pref.FieldNumber
|
|
}
|
|
|
|
func makeOneofInfo(od pref.OneofDescriptor, fs reflect.StructField, x exporter, wrappersByType map[reflect.Type]pref.FieldNumber) *oneofInfo {
|
|
fieldOffset := offsetOf(fs, x)
|
|
return &oneofInfo{
|
|
oneofDesc: od,
|
|
which: func(p pointer) pref.FieldNumber {
|
|
if p.IsNil() {
|
|
return 0
|
|
}
|
|
rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
|
|
if rv.IsNil() {
|
|
return 0
|
|
}
|
|
return wrappersByType[rv.Elem().Type().Elem()]
|
|
},
|
|
}
|
|
}
|
|
|
|
// defaultValueOf returns the default value for the field.
|
|
func defaultValueOf(fd pref.FieldDescriptor) pref.Value {
|
|
if fd == nil {
|
|
return pref.Value{}
|
|
}
|
|
pv := fd.Default() // invalid Value for messages and repeated fields
|
|
if fd.Kind() == pref.BytesKind && pv.IsValid() && len(pv.Bytes()) > 0 {
|
|
return pref.ValueOf(append([]byte(nil), pv.Bytes()...)) // copy default bytes for safety
|
|
}
|
|
return pv
|
|
}
|
|
|
|
// frozenValueOf returns a frozen version of any composite value.
|
|
func frozenValueOf(v pref.Value) pref.Value {
|
|
switch v := v.Interface().(type) {
|
|
case pref.Message:
|
|
if _, ok := v.(frozenMessage); !ok {
|
|
return pref.ValueOf(frozenMessage{v})
|
|
}
|
|
case pref.List:
|
|
if _, ok := v.(frozenList); !ok {
|
|
return pref.ValueOf(frozenList{v})
|
|
}
|
|
case pref.Map:
|
|
if _, ok := v.(frozenMap); !ok {
|
|
return pref.ValueOf(frozenMap{v})
|
|
}
|
|
}
|
|
return v
|
|
}
|
|
|
|
type frozenMessage struct{ pref.Message }
|
|
|
|
func (m frozenMessage) ProtoReflect() pref.Message { return m }
|
|
func (m frozenMessage) Interface() pref.ProtoMessage { return m }
|
|
func (m frozenMessage) Range(f func(pref.FieldDescriptor, pref.Value) bool) {
|
|
m.Message.Range(func(fd pref.FieldDescriptor, v pref.Value) bool {
|
|
return f(fd, frozenValueOf(v))
|
|
})
|
|
}
|
|
func (m frozenMessage) Get(fd pref.FieldDescriptor) pref.Value {
|
|
v := m.Message.Get(fd)
|
|
return frozenValueOf(v)
|
|
}
|
|
func (frozenMessage) Clear(pref.FieldDescriptor) { panic("invalid on read-only Message") }
|
|
func (frozenMessage) Set(pref.FieldDescriptor, pref.Value) { panic("invalid on read-only Message") }
|
|
func (frozenMessage) Mutable(pref.FieldDescriptor) pref.Value { panic("invalid on read-only Message") }
|
|
func (frozenMessage) SetUnknown(pref.RawFields) { panic("invalid on read-only Message") }
|
|
|
|
type frozenList struct{ pref.List }
|
|
|
|
func (ls frozenList) Get(i int) pref.Value {
|
|
v := ls.List.Get(i)
|
|
return frozenValueOf(v)
|
|
}
|
|
func (frozenList) Set(i int, v pref.Value) { panic("invalid on read-only List") }
|
|
func (frozenList) Append(v pref.Value) { panic("invalid on read-only List") }
|
|
func (frozenList) Truncate(i int) { panic("invalid on read-only List") }
|
|
|
|
type frozenMap struct{ pref.Map }
|
|
|
|
func (ms frozenMap) Get(k pref.MapKey) pref.Value {
|
|
v := ms.Map.Get(k)
|
|
return frozenValueOf(v)
|
|
}
|
|
func (ms frozenMap) Range(f func(pref.MapKey, pref.Value) bool) {
|
|
ms.Map.Range(func(k pref.MapKey, v pref.Value) bool {
|
|
return f(k, frozenValueOf(v))
|
|
})
|
|
}
|
|
func (frozenMap) Set(k pref.MapKey, v pref.Value) { panic("invalid n read-only Map") }
|
|
func (frozenMap) Clear(k pref.MapKey) { panic("invalid on read-only Map") }
|