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authorLibravatar dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>2025-01-14 13:10:39 +0000
committerLibravatar GitHub <noreply@github.com>2025-01-14 13:10:39 +0000
commit4d423102c14de9e9328f1852db539d9561a3cad9 (patch)
tree6df5905f53ad7eadbfa9840939989253bfb4b199 /vendor/google.golang.org/protobuf/internal/impl/message_opaque.go
parent[bugfix] migration to cleanup dropped status edits (#3637) (diff)
downloadgotosocial-4d423102c14de9e9328f1852db539d9561a3cad9.tar.xz
[chore]: Bump github.com/gin-contrib/gzip from 1.0.1 to 1.1.0 (#3639)
Bumps [github.com/gin-contrib/gzip](https://github.com/gin-contrib/gzip) from 1.0.1 to 1.1.0. - [Release notes](https://github.com/gin-contrib/gzip/releases) - [Changelog](https://github.com/gin-contrib/gzip/blob/master/.goreleaser.yaml) - [Commits](https://github.com/gin-contrib/gzip/compare/v1.0.1...v1.1.0) --- updated-dependencies: - dependency-name: github.com/gin-contrib/gzip dependency-type: direct:production update-type: version-update:semver-minor ... Signed-off-by: dependabot[bot] <support@github.com> Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Diffstat (limited to 'vendor/google.golang.org/protobuf/internal/impl/message_opaque.go')
-rw-r--r--vendor/google.golang.org/protobuf/internal/impl/message_opaque.go614
1 files changed, 614 insertions, 0 deletions
diff --git a/vendor/google.golang.org/protobuf/internal/impl/message_opaque.go b/vendor/google.golang.org/protobuf/internal/impl/message_opaque.go
new file mode 100644
index 000000000..d407dd791
--- /dev/null
+++ b/vendor/google.golang.org/protobuf/internal/impl/message_opaque.go
@@ -0,0 +1,614 @@
+// Copyright 2024 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"
+ "strings"
+ "sync/atomic"
+
+ "google.golang.org/protobuf/reflect/protoreflect"
+)
+
+type opaqueStructInfo struct {
+ structInfo
+}
+
+// isOpaque determines whether a protobuf message type is on the Opaque API. It
+// checks whether the type is a Go struct that protoc-gen-go would generate.
+//
+// This function only detects newly generated messages from the v2
+// implementation of protoc-gen-go. It is unable to classify generated messages
+// that are too old or those that are generated by a different generator
+// such as protoc-gen-gogo.
+func isOpaque(t reflect.Type) bool {
+ // The current detection mechanism is to simply check the first field
+ // for a struct tag with the "protogen" key.
+ if t.Kind() == reflect.Struct && t.NumField() > 0 {
+ pgt := t.Field(0).Tag.Get("protogen")
+ return strings.HasPrefix(pgt, "opaque.")
+ }
+ return false
+}
+
+func opaqueInitHook(mi *MessageInfo) bool {
+ mt := mi.GoReflectType.Elem()
+ si := opaqueStructInfo{
+ structInfo: mi.makeStructInfo(mt),
+ }
+
+ if !isOpaque(mt) {
+ return false
+ }
+
+ defer atomic.StoreUint32(&mi.initDone, 1)
+
+ mi.fields = map[protoreflect.FieldNumber]*fieldInfo{}
+ fds := mi.Desc.Fields()
+ for i := 0; i < fds.Len(); i++ {
+ fd := fds.Get(i)
+ fs := si.fieldsByNumber[fd.Number()]
+ var fi fieldInfo
+ usePresence, _ := usePresenceForField(si, fd)
+
+ switch {
+ case fd.IsWeak():
+ // Weak fields are no different for opaque.
+ fi = fieldInfoForWeakMessage(fd, si.weakOffset)
+ case fd.ContainingOneof() != nil && !fd.ContainingOneof().IsSynthetic():
+ // Oneofs are no different for opaque.
+ fi = fieldInfoForOneof(fd, si.oneofsByName[fd.ContainingOneof().Name()], mi.Exporter, si.oneofWrappersByNumber[fd.Number()])
+ case fd.IsMap():
+ fi = mi.fieldInfoForMapOpaque(si, fd, fs)
+ case fd.IsList() && fd.Message() == nil && usePresence:
+ fi = mi.fieldInfoForScalarListOpaque(si, fd, fs)
+ case fd.IsList() && fd.Message() == nil:
+ // Proto3 lists without presence can use same access methods as open
+ fi = fieldInfoForList(fd, fs, mi.Exporter)
+ case fd.IsList() && usePresence:
+ fi = mi.fieldInfoForMessageListOpaque(si, fd, fs)
+ case fd.IsList():
+ // Proto3 opaque messages that does not need presence bitmap.
+ // Different representation than open struct, but same logic
+ fi = mi.fieldInfoForMessageListOpaqueNoPresence(si, fd, fs)
+ case fd.Message() != nil && usePresence:
+ fi = mi.fieldInfoForMessageOpaque(si, fd, fs)
+ case fd.Message() != nil:
+ // Proto3 messages without presence can use same access methods as open
+ fi = fieldInfoForMessage(fd, fs, mi.Exporter)
+ default:
+ fi = mi.fieldInfoForScalarOpaque(si, fd, fs)
+ }
+ mi.fields[fd.Number()] = &fi
+ }
+ mi.oneofs = map[protoreflect.Name]*oneofInfo{}
+ for i := 0; i < mi.Desc.Oneofs().Len(); i++ {
+ od := mi.Desc.Oneofs().Get(i)
+ if !od.IsSynthetic() {
+ mi.oneofs[od.Name()] = makeOneofInfo(od, si.structInfo, mi.Exporter)
+ }
+ }
+
+ mi.denseFields = make([]*fieldInfo, fds.Len()*2)
+ for i := 0; i < fds.Len(); i++ {
+ if fd := fds.Get(i); int(fd.Number()) < len(mi.denseFields) {
+ mi.denseFields[fd.Number()] = mi.fields[fd.Number()]
+ }
+ }
+
+ for i := 0; i < fds.Len(); {
+ fd := fds.Get(i)
+ if od := fd.ContainingOneof(); od != nil && !fd.ContainingOneof().IsSynthetic() {
+ mi.rangeInfos = append(mi.rangeInfos, mi.oneofs[od.Name()])
+ i += od.Fields().Len()
+ } else {
+ mi.rangeInfos = append(mi.rangeInfos, mi.fields[fd.Number()])
+ i++
+ }
+ }
+
+ mi.makeExtensionFieldsFunc(mt, si.structInfo)
+ mi.makeUnknownFieldsFunc(mt, si.structInfo)
+ mi.makeOpaqueCoderMethods(mt, si)
+ mi.makeFieldTypes(si.structInfo)
+
+ return true
+}
+
+func (mi *MessageInfo) fieldInfoForMapOpaque(si opaqueStructInfo, fd protoreflect.FieldDescriptor, fs reflect.StructField) fieldInfo {
+ ft := fs.Type
+ if ft.Kind() != reflect.Map {
+ panic(fmt.Sprintf("invalid type: got %v, want map kind", ft))
+ }
+ fieldOffset := offsetOf(fs, mi.Exporter)
+ conv := NewConverter(ft, fd)
+ return fieldInfo{
+ fieldDesc: fd,
+ has: func(p pointer) bool {
+ if p.IsNil() {
+ return false
+ }
+ // Don't bother checking presence bits, since we need to
+ // look at the map length even if the presence bit is set.
+ 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) protoreflect.Value {
+ if p.IsNil() {
+ return conv.Zero()
+ }
+ rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
+ if rv.Len() == 0 {
+ return conv.Zero()
+ }
+ return conv.PBValueOf(rv)
+ },
+ set: func(p pointer, v protoreflect.Value) {
+ pv := conv.GoValueOf(v)
+ if pv.IsNil() {
+ panic(fmt.Sprintf("invalid value: setting map field to read-only value"))
+ }
+ rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
+ rv.Set(pv)
+ },
+ mutable: func(p pointer) protoreflect.Value {
+ v := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
+ if v.IsNil() {
+ v.Set(reflect.MakeMap(fs.Type))
+ }
+ return conv.PBValueOf(v)
+ },
+ newField: func() protoreflect.Value {
+ return conv.New()
+ },
+ }
+}
+
+func (mi *MessageInfo) fieldInfoForScalarListOpaque(si opaqueStructInfo, fd protoreflect.FieldDescriptor, fs reflect.StructField) 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)
+ fieldOffset := offsetOf(fs, mi.Exporter)
+ index, _ := presenceIndex(mi.Desc, fd)
+ 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) protoreflect.Value {
+ if p.IsNil() {
+ return conv.Zero()
+ }
+ rv := p.Apply(fieldOffset).AsValueOf(fs.Type)
+ if rv.Elem().Len() == 0 {
+ return conv.Zero()
+ }
+ return conv.PBValueOf(rv)
+ },
+ set: func(p pointer, v protoreflect.Value) {
+ pv := conv.GoValueOf(v)
+ if pv.IsNil() {
+ panic(fmt.Sprintf("invalid value: setting repeated field to read-only value"))
+ }
+ mi.setPresent(p, index)
+ rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
+ rv.Set(pv.Elem())
+ },
+ mutable: func(p pointer) protoreflect.Value {
+ mi.setPresent(p, index)
+ return conv.PBValueOf(p.Apply(fieldOffset).AsValueOf(fs.Type))
+ },
+ newField: func() protoreflect.Value {
+ return conv.New()
+ },
+ }
+}
+
+func (mi *MessageInfo) fieldInfoForMessageListOpaque(si opaqueStructInfo, fd protoreflect.FieldDescriptor, fs reflect.StructField) fieldInfo {
+ ft := fs.Type
+ if ft.Kind() != reflect.Ptr || ft.Elem().Kind() != reflect.Slice {
+ panic(fmt.Sprintf("invalid type: got %v, want slice kind", ft))
+ }
+ conv := NewConverter(ft, fd)
+ fieldOffset := offsetOf(fs, mi.Exporter)
+ index, _ := presenceIndex(mi.Desc, fd)
+ fieldNumber := fd.Number()
+ return fieldInfo{
+ fieldDesc: fd,
+ has: func(p pointer) bool {
+ if p.IsNil() {
+ return false
+ }
+ if !mi.present(p, index) {
+ return false
+ }
+ sp := p.Apply(fieldOffset).AtomicGetPointer()
+ if sp.IsNil() {
+ // Lazily unmarshal this field.
+ mi.lazyUnmarshal(p, fieldNumber)
+ sp = p.Apply(fieldOffset).AtomicGetPointer()
+ }
+ rv := sp.AsValueOf(fs.Type.Elem())
+ return rv.Elem().Len() > 0
+ },
+ clear: func(p pointer) {
+ fp := p.Apply(fieldOffset)
+ sp := fp.AtomicGetPointer()
+ if sp.IsNil() {
+ sp = fp.AtomicSetPointerIfNil(pointerOfValue(reflect.New(fs.Type.Elem())))
+ mi.setPresent(p, index)
+ }
+ rv := sp.AsValueOf(fs.Type.Elem())
+ rv.Elem().Set(reflect.Zero(rv.Type().Elem()))
+ },
+ get: func(p pointer) protoreflect.Value {
+ if p.IsNil() {
+ return conv.Zero()
+ }
+ if !mi.present(p, index) {
+ return conv.Zero()
+ }
+ sp := p.Apply(fieldOffset).AtomicGetPointer()
+ if sp.IsNil() {
+ // Lazily unmarshal this field.
+ mi.lazyUnmarshal(p, fieldNumber)
+ sp = p.Apply(fieldOffset).AtomicGetPointer()
+ }
+ rv := sp.AsValueOf(fs.Type.Elem())
+ if rv.Elem().Len() == 0 {
+ return conv.Zero()
+ }
+ return conv.PBValueOf(rv)
+ },
+ set: func(p pointer, v protoreflect.Value) {
+ fp := p.Apply(fieldOffset)
+ sp := fp.AtomicGetPointer()
+ if sp.IsNil() {
+ sp = fp.AtomicSetPointerIfNil(pointerOfValue(reflect.New(fs.Type.Elem())))
+ mi.setPresent(p, index)
+ }
+ rv := sp.AsValueOf(fs.Type.Elem())
+ val := conv.GoValueOf(v)
+ if val.IsNil() {
+ panic(fmt.Sprintf("invalid value: setting repeated field to read-only value"))
+ } else {
+ rv.Elem().Set(val.Elem())
+ }
+ },
+ mutable: func(p pointer) protoreflect.Value {
+ fp := p.Apply(fieldOffset)
+ sp := fp.AtomicGetPointer()
+ if sp.IsNil() {
+ if mi.present(p, index) {
+ // Lazily unmarshal this field.
+ mi.lazyUnmarshal(p, fieldNumber)
+ sp = p.Apply(fieldOffset).AtomicGetPointer()
+ } else {
+ sp = fp.AtomicSetPointerIfNil(pointerOfValue(reflect.New(fs.Type.Elem())))
+ mi.setPresent(p, index)
+ }
+ }
+ rv := sp.AsValueOf(fs.Type.Elem())
+ return conv.PBValueOf(rv)
+ },
+ newField: func() protoreflect.Value {
+ return conv.New()
+ },
+ }
+}
+
+func (mi *MessageInfo) fieldInfoForMessageListOpaqueNoPresence(si opaqueStructInfo, fd protoreflect.FieldDescriptor, fs reflect.StructField) fieldInfo {
+ ft := fs.Type
+ if ft.Kind() != reflect.Ptr || ft.Elem().Kind() != reflect.Slice {
+ panic(fmt.Sprintf("invalid type: got %v, want slice kind", ft))
+ }
+ conv := NewConverter(ft, fd)
+ fieldOffset := offsetOf(fs, mi.Exporter)
+ return fieldInfo{
+ fieldDesc: fd,
+ has: func(p pointer) bool {
+ if p.IsNil() {
+ return false
+ }
+ sp := p.Apply(fieldOffset).AtomicGetPointer()
+ if sp.IsNil() {
+ return false
+ }
+ rv := sp.AsValueOf(fs.Type.Elem())
+ return rv.Elem().Len() > 0
+ },
+ clear: func(p pointer) {
+ sp := p.Apply(fieldOffset).AtomicGetPointer()
+ if !sp.IsNil() {
+ rv := sp.AsValueOf(fs.Type.Elem())
+ rv.Elem().Set(reflect.Zero(rv.Type().Elem()))
+ }
+ },
+ get: func(p pointer) protoreflect.Value {
+ if p.IsNil() {
+ return conv.Zero()
+ }
+ sp := p.Apply(fieldOffset).AtomicGetPointer()
+ if sp.IsNil() {
+ return conv.Zero()
+ }
+ rv := sp.AsValueOf(fs.Type.Elem())
+ if rv.Elem().Len() == 0 {
+ return conv.Zero()
+ }
+ return conv.PBValueOf(rv)
+ },
+ set: func(p pointer, v protoreflect.Value) {
+ rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
+ if rv.IsNil() {
+ rv.Set(reflect.New(fs.Type.Elem()))
+ }
+ val := conv.GoValueOf(v)
+ if val.IsNil() {
+ panic(fmt.Sprintf("invalid value: setting repeated field to read-only value"))
+ } else {
+ rv.Elem().Set(val.Elem())
+ }
+ },
+ mutable: func(p pointer) protoreflect.Value {
+ rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
+ if rv.IsNil() {
+ rv.Set(reflect.New(fs.Type.Elem()))
+ }
+ return conv.PBValueOf(rv)
+ },
+ newField: func() protoreflect.Value {
+ return conv.New()
+ },
+ }
+}
+
+func (mi *MessageInfo) fieldInfoForScalarOpaque(si opaqueStructInfo, fd protoreflect.FieldDescriptor, fs reflect.StructField) fieldInfo {
+ ft := fs.Type
+ nullable := fd.HasPresence()
+ if oneof := fd.ContainingOneof(); oneof != nil && oneof.IsSynthetic() {
+ nullable = true
+ }
+ deref := false
+ if nullable && ft.Kind() == reflect.Ptr {
+ ft = ft.Elem()
+ deref = true
+ }
+ conv := NewConverter(ft, fd)
+ fieldOffset := offsetOf(fs, mi.Exporter)
+ index, _ := presenceIndex(mi.Desc, fd)
+ var getter func(p pointer) protoreflect.Value
+ if !nullable {
+ getter = getterForDirectScalar(fd, fs, conv, fieldOffset)
+ } else {
+ getter = getterForOpaqueNullableScalar(mi, index, fd, fs, conv, fieldOffset)
+ }
+ return fieldInfo{
+ fieldDesc: fd,
+ has: func(p pointer) bool {
+ if p.IsNil() {
+ return false
+ }
+ if nullable {
+ return mi.present(p, index)
+ }
+ rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
+ 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) {
+ if nullable {
+ mi.clearPresent(p, index)
+ }
+ // This is only valuable for bytes and strings, but we do it unconditionally.
+ rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
+ rv.Set(reflect.Zero(rv.Type()))
+ },
+ get: getter,
+ // TODO: Implement unsafe fast path for set?
+ set: func(p pointer, v protoreflect.Value) {
+ rv := p.Apply(fieldOffset).AsValueOf(fs.Type).Elem()
+ if deref {
+ if rv.IsNil() {
+ rv.Set(reflect.New(ft))
+ }
+ rv = rv.Elem()
+ }
+
+ rv.Set(conv.GoValueOf(v))
+ if nullable && rv.Kind() == reflect.Slice && rv.IsNil() {
+ rv.Set(emptyBytes)
+ }
+ if nullable {
+ mi.setPresent(p, index)
+ }
+ },
+ newField: func() protoreflect.Value {
+ return conv.New()
+ },
+ }
+}
+
+func (mi *MessageInfo) fieldInfoForMessageOpaque(si opaqueStructInfo, fd protoreflect.FieldDescriptor, fs reflect.StructField) fieldInfo {
+ ft := fs.Type
+ conv := NewConverter(ft, fd)
+ fieldOffset := offsetOf(fs, mi.Exporter)
+ index, _ := presenceIndex(mi.Desc, fd)
+ fieldNumber := fd.Number()
+ elemType := fs.Type.Elem()
+ return fieldInfo{
+ fieldDesc: fd,
+ has: func(p pointer) bool {
+ if p.IsNil() {
+ return false
+ }
+ return mi.present(p, index)
+ },
+ clear: func(p pointer) {
+ mi.clearPresent(p, index)
+ p.Apply(fieldOffset).AtomicSetNilPointer()
+ },
+ get: func(p pointer) protoreflect.Value {
+ if p.IsNil() || !mi.present(p, index) {
+ return conv.Zero()
+ }
+ fp := p.Apply(fieldOffset)
+ mp := fp.AtomicGetPointer()
+ if mp.IsNil() {
+ // Lazily unmarshal this field.
+ mi.lazyUnmarshal(p, fieldNumber)
+ mp = fp.AtomicGetPointer()
+ }
+ rv := mp.AsValueOf(elemType)
+ return conv.PBValueOf(rv)
+ },
+ set: func(p pointer, v protoreflect.Value) {
+ val := pointerOfValue(conv.GoValueOf(v))
+ if val.IsNil() {
+ panic("invalid nil pointer")
+ }
+ p.Apply(fieldOffset).AtomicSetPointer(val)
+ mi.setPresent(p, index)
+ },
+ mutable: func(p pointer) protoreflect.Value {
+ fp := p.Apply(fieldOffset)
+ mp := fp.AtomicGetPointer()
+ if mp.IsNil() {
+ if mi.present(p, index) {
+ // Lazily unmarshal this field.
+ mi.lazyUnmarshal(p, fieldNumber)
+ mp = fp.AtomicGetPointer()
+ } else {
+ mp = pointerOfValue(conv.GoValueOf(conv.New()))
+ fp.AtomicSetPointer(mp)
+ mi.setPresent(p, index)
+ }
+ }
+ return conv.PBValueOf(mp.AsValueOf(fs.Type.Elem()))
+ },
+ newMessage: func() protoreflect.Message {
+ return conv.New().Message()
+ },
+ newField: func() protoreflect.Value {
+ return conv.New()
+ },
+ }
+}
+
+// A presenceList wraps a List, updating presence bits as necessary when the
+// list contents change.
+type presenceList struct {
+ pvalueList
+ setPresence func(bool)
+}
+type pvalueList interface {
+ protoreflect.List
+ //Unwrapper
+}
+
+func (list presenceList) Append(v protoreflect.Value) {
+ list.pvalueList.Append(v)
+ list.setPresence(true)
+}
+func (list presenceList) Truncate(i int) {
+ list.pvalueList.Truncate(i)
+ list.setPresence(i > 0)
+}
+
+// presenceIndex returns the index to pass to presence functions.
+//
+// TODO: field.Desc.Index() would be simpler, and would give space to record the presence of oneof fields.
+func presenceIndex(md protoreflect.MessageDescriptor, fd protoreflect.FieldDescriptor) (uint32, presenceSize) {
+ found := false
+ var index, numIndices uint32
+ for i := 0; i < md.Fields().Len(); i++ {
+ f := md.Fields().Get(i)
+ if f == fd {
+ found = true
+ index = numIndices
+ }
+ if f.ContainingOneof() == nil || isLastOneofField(f) {
+ numIndices++
+ }
+ }
+ if !found {
+ panic(fmt.Sprintf("BUG: %v not in %v", fd.Name(), md.FullName()))
+ }
+ return index, presenceSize(numIndices)
+}
+
+func isLastOneofField(fd protoreflect.FieldDescriptor) bool {
+ fields := fd.ContainingOneof().Fields()
+ return fields.Get(fields.Len()-1) == fd
+}
+
+func (mi *MessageInfo) setPresent(p pointer, index uint32) {
+ p.Apply(mi.presenceOffset).PresenceInfo().SetPresent(index, mi.presenceSize)
+}
+
+func (mi *MessageInfo) clearPresent(p pointer, index uint32) {
+ p.Apply(mi.presenceOffset).PresenceInfo().ClearPresent(index)
+}
+
+func (mi *MessageInfo) present(p pointer, index uint32) bool {
+ return p.Apply(mi.presenceOffset).PresenceInfo().Present(index)
+}
+
+// usePresenceForField implements the somewhat intricate logic of when
+// the presence bitmap is used for a field. The main logic is that a
+// field that is optional or that can be lazy will use the presence
+// bit, but for proto2, also maps have a presence bit. It also records
+// if the field can ever be lazy, which is true if we have a
+// lazyOffset and the field is a message or a slice of messages. A
+// field that is lazy will always need a presence bit. Oneofs are not
+// lazy and do not use presence, unless they are a synthetic oneof,
+// which is a proto3 optional field. For proto3 optionals, we use the
+// presence and they can also be lazy when applicable (a message).
+func usePresenceForField(si opaqueStructInfo, fd protoreflect.FieldDescriptor) (usePresence, canBeLazy bool) {
+ hasLazyField := fd.(interface{ IsLazy() bool }).IsLazy()
+
+ // Non-oneof scalar fields with explicit field presence use the presence array.
+ usesPresenceArray := fd.HasPresence() && fd.Message() == nil && (fd.ContainingOneof() == nil || fd.ContainingOneof().IsSynthetic())
+ switch {
+ case fd.ContainingOneof() != nil && !fd.ContainingOneof().IsSynthetic():
+ return false, false
+ case fd.IsWeak():
+ return false, false
+ case fd.IsMap():
+ return false, false
+ case fd.Kind() == protoreflect.MessageKind || fd.Kind() == protoreflect.GroupKind:
+ return hasLazyField, hasLazyField
+ default:
+ return usesPresenceArray || (hasLazyField && fd.HasPresence()), false
+ }
+}