githaven-fork/vendor/google.golang.org/protobuf/internal/impl/encode.go

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// 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 impl
import (
"math"
"sort"
"sync/atomic"
"google.golang.org/protobuf/internal/flags"
proto "google.golang.org/protobuf/proto"
piface "google.golang.org/protobuf/runtime/protoiface"
)
type marshalOptions struct {
flags piface.MarshalInputFlags
}
func (o marshalOptions) Options() proto.MarshalOptions {
return proto.MarshalOptions{
AllowPartial: true,
Deterministic: o.Deterministic(),
UseCachedSize: o.UseCachedSize(),
}
}
func (o marshalOptions) Deterministic() bool { return o.flags&piface.MarshalDeterministic != 0 }
func (o marshalOptions) UseCachedSize() bool { return o.flags&piface.MarshalUseCachedSize != 0 }
// size is protoreflect.Methods.Size.
func (mi *MessageInfo) size(in piface.SizeInput) piface.SizeOutput {
var p pointer
if ms, ok := in.Message.(*messageState); ok {
p = ms.pointer()
} else {
p = in.Message.(*messageReflectWrapper).pointer()
}
size := mi.sizePointer(p, marshalOptions{
flags: in.Flags,
})
return piface.SizeOutput{Size: size}
}
func (mi *MessageInfo) sizePointer(p pointer, opts marshalOptions) (size int) {
mi.init()
if p.IsNil() {
return 0
}
if opts.UseCachedSize() && mi.sizecacheOffset.IsValid() {
if size := atomic.LoadInt32(p.Apply(mi.sizecacheOffset).Int32()); size >= 0 {
return int(size)
}
}
return mi.sizePointerSlow(p, opts)
}
func (mi *MessageInfo) sizePointerSlow(p pointer, opts marshalOptions) (size int) {
if flags.ProtoLegacy && mi.isMessageSet {
size = sizeMessageSet(mi, p, opts)
if mi.sizecacheOffset.IsValid() {
atomic.StoreInt32(p.Apply(mi.sizecacheOffset).Int32(), int32(size))
}
return size
}
if mi.extensionOffset.IsValid() {
e := p.Apply(mi.extensionOffset).Extensions()
size += mi.sizeExtensions(e, opts)
}
for _, f := range mi.orderedCoderFields {
if f.funcs.size == nil {
continue
}
fptr := p.Apply(f.offset)
if f.isPointer && fptr.Elem().IsNil() {
continue
}
size += f.funcs.size(fptr, f, opts)
}
if mi.unknownOffset.IsValid() {
u := *p.Apply(mi.unknownOffset).Bytes()
size += len(u)
}
if mi.sizecacheOffset.IsValid() {
if size > math.MaxInt32 {
// The size is too large for the int32 sizecache field.
// We will need to recompute the size when encoding;
// unfortunately expensive, but better than invalid output.
atomic.StoreInt32(p.Apply(mi.sizecacheOffset).Int32(), -1)
} else {
atomic.StoreInt32(p.Apply(mi.sizecacheOffset).Int32(), int32(size))
}
}
return size
}
// marshal is protoreflect.Methods.Marshal.
func (mi *MessageInfo) marshal(in piface.MarshalInput) (out piface.MarshalOutput, err error) {
var p pointer
if ms, ok := in.Message.(*messageState); ok {
p = ms.pointer()
} else {
p = in.Message.(*messageReflectWrapper).pointer()
}
b, err := mi.marshalAppendPointer(in.Buf, p, marshalOptions{
flags: in.Flags,
})
return piface.MarshalOutput{Buf: b}, err
}
func (mi *MessageInfo) marshalAppendPointer(b []byte, p pointer, opts marshalOptions) ([]byte, error) {
mi.init()
if p.IsNil() {
return b, nil
}
if flags.ProtoLegacy && mi.isMessageSet {
return marshalMessageSet(mi, b, p, opts)
}
var err error
// The old marshaler encodes extensions at beginning.
if mi.extensionOffset.IsValid() {
e := p.Apply(mi.extensionOffset).Extensions()
// TODO: Special handling for MessageSet?
b, err = mi.appendExtensions(b, e, opts)
if err != nil {
return b, err
}
}
for _, f := range mi.orderedCoderFields {
if f.funcs.marshal == nil {
continue
}
fptr := p.Apply(f.offset)
if f.isPointer && fptr.Elem().IsNil() {
continue
}
b, err = f.funcs.marshal(b, fptr, f, opts)
if err != nil {
return b, err
}
}
if mi.unknownOffset.IsValid() && !mi.isMessageSet {
u := *p.Apply(mi.unknownOffset).Bytes()
b = append(b, u...)
}
return b, nil
}
func (mi *MessageInfo) sizeExtensions(ext *map[int32]ExtensionField, opts marshalOptions) (n int) {
if ext == nil {
return 0
}
for _, x := range *ext {
xi := getExtensionFieldInfo(x.Type())
if xi.funcs.size == nil {
continue
}
n += xi.funcs.size(x.Value(), xi.tagsize, opts)
}
return n
}
func (mi *MessageInfo) appendExtensions(b []byte, ext *map[int32]ExtensionField, opts marshalOptions) ([]byte, error) {
if ext == nil {
return b, nil
}
switch len(*ext) {
case 0:
return b, nil
case 1:
// Fast-path for one extension: Don't bother sorting the keys.
var err error
for _, x := range *ext {
xi := getExtensionFieldInfo(x.Type())
b, err = xi.funcs.marshal(b, x.Value(), xi.wiretag, opts)
}
return b, err
default:
// Sort the keys to provide a deterministic encoding.
// Not sure this is required, but the old code does it.
keys := make([]int, 0, len(*ext))
for k := range *ext {
keys = append(keys, int(k))
}
sort.Ints(keys)
var err error
for _, k := range keys {
x := (*ext)[int32(k)]
xi := getExtensionFieldInfo(x.Type())
b, err = xi.funcs.marshal(b, x.Value(), xi.wiretag, opts)
if err != nil {
return b, err
}
}
return b, nil
}
}