diff options
Diffstat (limited to 'vendor/github.com/golang/protobuf/proto/extensions.go')
-rw-r--r-- | vendor/github.com/golang/protobuf/proto/extensions.go | 356 |
1 files changed, 356 insertions, 0 deletions
diff --git a/vendor/github.com/golang/protobuf/proto/extensions.go b/vendor/github.com/golang/protobuf/proto/extensions.go new file mode 100644 index 0000000000..42fc120c97 --- /dev/null +++ b/vendor/github.com/golang/protobuf/proto/extensions.go @@ -0,0 +1,356 @@ +// Copyright 2010 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 ( + "errors" + "fmt" + "reflect" + + "google.golang.org/protobuf/encoding/protowire" + "google.golang.org/protobuf/proto" + "google.golang.org/protobuf/reflect/protoreflect" + "google.golang.org/protobuf/reflect/protoregistry" + "google.golang.org/protobuf/runtime/protoiface" + "google.golang.org/protobuf/runtime/protoimpl" +) + +type ( + // ExtensionDesc represents an extension descriptor and + // is used to interact with an extension field in a message. + // + // Variables of this type are generated in code by protoc-gen-go. + ExtensionDesc = protoimpl.ExtensionInfo + + // ExtensionRange represents a range of message extensions. + // Used in code generated by protoc-gen-go. + ExtensionRange = protoiface.ExtensionRangeV1 + + // Deprecated: Do not use; this is an internal type. + Extension = protoimpl.ExtensionFieldV1 + + // Deprecated: Do not use; this is an internal type. + XXX_InternalExtensions = protoimpl.ExtensionFields +) + +// ErrMissingExtension reports whether the extension was not present. +var ErrMissingExtension = errors.New("proto: missing extension") + +var errNotExtendable = errors.New("proto: not an extendable proto.Message") + +// HasExtension reports whether the extension field is present in m +// either as an explicitly populated field or as an unknown field. +func HasExtension(m Message, xt *ExtensionDesc) (has bool) { + mr := MessageReflect(m) + if mr == nil || !mr.IsValid() { + return false + } + + // Check whether any populated known field matches the field number. + xtd := xt.TypeDescriptor() + if isValidExtension(mr.Descriptor(), xtd) { + has = mr.Has(xtd) + } else { + mr.Range(func(fd protoreflect.FieldDescriptor, _ protoreflect.Value) bool { + has = int32(fd.Number()) == xt.Field + return !has + }) + } + + // Check whether any unknown field matches the field number. + for b := mr.GetUnknown(); !has && len(b) > 0; { + num, _, n := protowire.ConsumeField(b) + has = int32(num) == xt.Field + b = b[n:] + } + return has +} + +// ClearExtension removes the extension field from m +// either as an explicitly populated field or as an unknown field. +func ClearExtension(m Message, xt *ExtensionDesc) { + mr := MessageReflect(m) + if mr == nil || !mr.IsValid() { + return + } + + xtd := xt.TypeDescriptor() + if isValidExtension(mr.Descriptor(), xtd) { + mr.Clear(xtd) + } else { + mr.Range(func(fd protoreflect.FieldDescriptor, _ protoreflect.Value) bool { + if int32(fd.Number()) == xt.Field { + mr.Clear(fd) + return false + } + return true + }) + } + clearUnknown(mr, fieldNum(xt.Field)) +} + +// ClearAllExtensions clears all extensions from m. +// This includes populated fields and unknown fields in the extension range. +func ClearAllExtensions(m Message) { + mr := MessageReflect(m) + if mr == nil || !mr.IsValid() { + return + } + + mr.Range(func(fd protoreflect.FieldDescriptor, _ protoreflect.Value) bool { + if fd.IsExtension() { + mr.Clear(fd) + } + return true + }) + clearUnknown(mr, mr.Descriptor().ExtensionRanges()) +} + +// GetExtension retrieves a proto2 extended field from m. +// +// If the descriptor is type complete (i.e., ExtensionDesc.ExtensionType is non-nil), +// then GetExtension parses the encoded field and returns a Go value of the specified type. +// If the field is not present, then the default value is returned (if one is specified), +// otherwise ErrMissingExtension is reported. +// +// If the descriptor is type incomplete (i.e., ExtensionDesc.ExtensionType is nil), +// then GetExtension returns the raw encoded bytes for the extension field. +func GetExtension(m Message, xt *ExtensionDesc) (interface{}, error) { + mr := MessageReflect(m) + if mr == nil || !mr.IsValid() || mr.Descriptor().ExtensionRanges().Len() == 0 { + return nil, errNotExtendable + } + + // Retrieve the unknown fields for this extension field. + var bo protoreflect.RawFields + for bi := mr.GetUnknown(); len(bi) > 0; { + num, _, n := protowire.ConsumeField(bi) + if int32(num) == xt.Field { + bo = append(bo, bi[:n]...) + } + bi = bi[n:] + } + + // For type incomplete descriptors, only retrieve the unknown fields. + if xt.ExtensionType == nil { + return []byte(bo), nil + } + + // If the extension field only exists as unknown fields, unmarshal it. + // This is rarely done since proto.Unmarshal eagerly unmarshals extensions. + xtd := xt.TypeDescriptor() + if !isValidExtension(mr.Descriptor(), xtd) { + return nil, fmt.Errorf("proto: bad extended type; %T does not extend %T", xt.ExtendedType, m) + } + if !mr.Has(xtd) && len(bo) > 0 { + m2 := mr.New() + if err := (proto.UnmarshalOptions{ + Resolver: extensionResolver{xt}, + }.Unmarshal(bo, m2.Interface())); err != nil { + return nil, err + } + if m2.Has(xtd) { + mr.Set(xtd, m2.Get(xtd)) + clearUnknown(mr, fieldNum(xt.Field)) + } + } + + // Check whether the message has the extension field set or a default. + var pv protoreflect.Value + switch { + case mr.Has(xtd): + pv = mr.Get(xtd) + case xtd.HasDefault(): + pv = xtd.Default() + default: + return nil, ErrMissingExtension + } + + v := xt.InterfaceOf(pv) + rv := reflect.ValueOf(v) + if isScalarKind(rv.Kind()) { + rv2 := reflect.New(rv.Type()) + rv2.Elem().Set(rv) + v = rv2.Interface() + } + return v, nil +} + +// extensionResolver is a custom extension resolver that stores a single +// extension type that takes precedence over the global registry. +type extensionResolver struct{ xt protoreflect.ExtensionType } + +func (r extensionResolver) FindExtensionByName(field protoreflect.FullName) (protoreflect.ExtensionType, error) { + if xtd := r.xt.TypeDescriptor(); xtd.FullName() == field { + return r.xt, nil + } + return protoregistry.GlobalTypes.FindExtensionByName(field) +} + +func (r extensionResolver) FindExtensionByNumber(message protoreflect.FullName, field protoreflect.FieldNumber) (protoreflect.ExtensionType, error) { + if xtd := r.xt.TypeDescriptor(); xtd.ContainingMessage().FullName() == message && xtd.Number() == field { + return r.xt, nil + } + return protoregistry.GlobalTypes.FindExtensionByNumber(message, field) +} + +// GetExtensions returns a list of the extensions values present in m, +// corresponding with the provided list of extension descriptors, xts. +// If an extension is missing in m, the corresponding value is nil. +func GetExtensions(m Message, xts []*ExtensionDesc) ([]interface{}, error) { + mr := MessageReflect(m) + if mr == nil || !mr.IsValid() { + return nil, errNotExtendable + } + + vs := make([]interface{}, len(xts)) + for i, xt := range xts { + v, err := GetExtension(m, xt) + if err != nil { + if err == ErrMissingExtension { + continue + } + return vs, err + } + vs[i] = v + } + return vs, nil +} + +// SetExtension sets an extension field in m to the provided value. +func SetExtension(m Message, xt *ExtensionDesc, v interface{}) error { + mr := MessageReflect(m) + if mr == nil || !mr.IsValid() || mr.Descriptor().ExtensionRanges().Len() == 0 { + return errNotExtendable + } + + rv := reflect.ValueOf(v) + if reflect.TypeOf(v) != reflect.TypeOf(xt.ExtensionType) { + return fmt.Errorf("proto: bad extension value type. got: %T, want: %T", v, xt.ExtensionType) + } + if rv.Kind() == reflect.Ptr { + if rv.IsNil() { + return fmt.Errorf("proto: SetExtension called with nil value of type %T", v) + } + if isScalarKind(rv.Elem().Kind()) { + v = rv.Elem().Interface() + } + } + + xtd := xt.TypeDescriptor() + if !isValidExtension(mr.Descriptor(), xtd) { + return fmt.Errorf("proto: bad extended type; %T does not extend %T", xt.ExtendedType, m) + } + mr.Set(xtd, xt.ValueOf(v)) + clearUnknown(mr, fieldNum(xt.Field)) + return nil +} + +// SetRawExtension inserts b into the unknown fields of m. +// +// Deprecated: Use Message.ProtoReflect.SetUnknown instead. +func SetRawExtension(m Message, fnum int32, b []byte) { + mr := MessageReflect(m) + if mr == nil || !mr.IsValid() { + return + } + + // Verify that the raw field is valid. + for b0 := b; len(b0) > 0; { + num, _, n := protowire.ConsumeField(b0) + if int32(num) != fnum { + panic(fmt.Sprintf("mismatching field number: got %d, want %d", num, fnum)) + } + b0 = b0[n:] + } + + ClearExtension(m, &ExtensionDesc{Field: fnum}) + mr.SetUnknown(append(mr.GetUnknown(), b...)) +} + +// ExtensionDescs returns a list of extension descriptors found in m, +// containing descriptors for both populated extension fields in m and +// also unknown fields of m that are in the extension range. +// For the later case, an type incomplete descriptor is provided where only +// the ExtensionDesc.Field field is populated. +// The order of the extension descriptors is undefined. +func ExtensionDescs(m Message) ([]*ExtensionDesc, error) { + mr := MessageReflect(m) + if mr == nil || !mr.IsValid() || mr.Descriptor().ExtensionRanges().Len() == 0 { + return nil, errNotExtendable + } + + // Collect a set of known extension descriptors. + extDescs := make(map[protoreflect.FieldNumber]*ExtensionDesc) + mr.Range(func(fd protoreflect.FieldDescriptor, v protoreflect.Value) bool { + if fd.IsExtension() { + xt := fd.(protoreflect.ExtensionTypeDescriptor) + if xd, ok := xt.Type().(*ExtensionDesc); ok { + extDescs[fd.Number()] = xd + } + } + return true + }) + + // Collect a set of unknown extension descriptors. + extRanges := mr.Descriptor().ExtensionRanges() + for b := mr.GetUnknown(); len(b) > 0; { + num, _, n := protowire.ConsumeField(b) + if extRanges.Has(num) && extDescs[num] == nil { + extDescs[num] = nil + } + b = b[n:] + } + + // Transpose the set of descriptors into a list. + var xts []*ExtensionDesc + for num, xt := range extDescs { + if xt == nil { + xt = &ExtensionDesc{Field: int32(num)} + } + xts = append(xts, xt) + } + return xts, nil +} + +// isValidExtension reports whether xtd is a valid extension descriptor for md. +func isValidExtension(md protoreflect.MessageDescriptor, xtd protoreflect.ExtensionTypeDescriptor) bool { + return xtd.ContainingMessage() == md && md.ExtensionRanges().Has(xtd.Number()) +} + +// isScalarKind reports whether k is a protobuf scalar kind (except bytes). +// This function exists for historical reasons since the representation of +// scalars differs between v1 and v2, where v1 uses *T and v2 uses T. +func isScalarKind(k reflect.Kind) bool { + switch k { + case reflect.Bool, reflect.Int32, reflect.Int64, reflect.Uint32, reflect.Uint64, reflect.Float32, reflect.Float64, reflect.String: + return true + default: + return false + } +} + +// clearUnknown removes unknown fields from m where remover.Has reports true. +func clearUnknown(m protoreflect.Message, remover interface { + Has(protoreflect.FieldNumber) bool +}) { + var bo protoreflect.RawFields + for bi := m.GetUnknown(); len(bi) > 0; { + num, _, n := protowire.ConsumeField(bi) + if !remover.Has(num) { + bo = append(bo, bi[:n]...) + } + bi = bi[n:] + } + if bi := m.GetUnknown(); len(bi) != len(bo) { + m.SetUnknown(bo) + } +} + +type fieldNum protoreflect.FieldNumber + +func (n1 fieldNum) Has(n2 protoreflect.FieldNumber) bool { + return protoreflect.FieldNumber(n1) == n2 +} |