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Diffstat (limited to 'vendor/google.golang.org/protobuf/proto/decode.go')
-rw-r--r-- | vendor/google.golang.org/protobuf/proto/decode.go | 270 |
1 files changed, 270 insertions, 0 deletions
diff --git a/vendor/google.golang.org/protobuf/proto/decode.go b/vendor/google.golang.org/protobuf/proto/decode.go new file mode 100644 index 000000000..128214760 --- /dev/null +++ b/vendor/google.golang.org/protobuf/proto/decode.go @@ -0,0 +1,270 @@ +// 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 proto + +import ( + "google.golang.org/protobuf/encoding/protowire" + "google.golang.org/protobuf/internal/encoding/messageset" + "google.golang.org/protobuf/internal/errors" + "google.golang.org/protobuf/internal/flags" + "google.golang.org/protobuf/internal/pragma" + "google.golang.org/protobuf/reflect/protoreflect" + "google.golang.org/protobuf/reflect/protoregistry" + "google.golang.org/protobuf/runtime/protoiface" +) + +// UnmarshalOptions configures the unmarshaler. +// +// Example usage: +// err := UnmarshalOptions{DiscardUnknown: true}.Unmarshal(b, m) +type UnmarshalOptions struct { + pragma.NoUnkeyedLiterals + + // Merge merges the input into the destination message. + // The default behavior is to always reset the message before unmarshaling, + // unless Merge is specified. + Merge bool + + // AllowPartial accepts input for messages that will result in missing + // required fields. If AllowPartial is false (the default), Unmarshal will + // return an error if there are any missing required fields. + AllowPartial bool + + // If DiscardUnknown is set, unknown fields are ignored. + DiscardUnknown bool + + // Resolver is used for looking up types when unmarshaling extension fields. + // If nil, this defaults to using protoregistry.GlobalTypes. + Resolver interface { + FindExtensionByName(field protoreflect.FullName) (protoreflect.ExtensionType, error) + FindExtensionByNumber(message protoreflect.FullName, field protoreflect.FieldNumber) (protoreflect.ExtensionType, error) + } +} + +// Unmarshal parses the wire-format message in b and places the result in m. +func Unmarshal(b []byte, m Message) error { + _, err := UnmarshalOptions{}.unmarshal(b, m.ProtoReflect()) + return err +} + +// Unmarshal parses the wire-format message in b and places the result in m. +func (o UnmarshalOptions) Unmarshal(b []byte, m Message) error { + _, err := o.unmarshal(b, m.ProtoReflect()) + return err +} + +// UnmarshalState parses a wire-format message and places the result in m. +// +// This method permits fine-grained control over the unmarshaler. +// Most users should use Unmarshal instead. +func (o UnmarshalOptions) UnmarshalState(in protoiface.UnmarshalInput) (protoiface.UnmarshalOutput, error) { + return o.unmarshal(in.Buf, in.Message) +} + +func (o UnmarshalOptions) unmarshal(b []byte, m protoreflect.Message) (out protoiface.UnmarshalOutput, err error) { + if o.Resolver == nil { + o.Resolver = protoregistry.GlobalTypes + } + if !o.Merge { + Reset(m.Interface()) // TODO + } + allowPartial := o.AllowPartial + o.Merge = true + o.AllowPartial = true + methods := protoMethods(m) + if methods != nil && methods.Unmarshal != nil && + !(o.DiscardUnknown && methods.Flags&protoiface.SupportUnmarshalDiscardUnknown == 0) { + in := protoiface.UnmarshalInput{ + Message: m, + Buf: b, + Resolver: o.Resolver, + } + if o.DiscardUnknown { + in.Flags |= protoiface.UnmarshalDiscardUnknown + } + out, err = methods.Unmarshal(in) + } else { + err = o.unmarshalMessageSlow(b, m) + } + if err != nil { + return out, err + } + if allowPartial || (out.Flags&protoiface.UnmarshalInitialized != 0) { + return out, nil + } + return out, checkInitialized(m) +} + +func (o UnmarshalOptions) unmarshalMessage(b []byte, m protoreflect.Message) error { + _, err := o.unmarshal(b, m) + return err +} + +func (o UnmarshalOptions) unmarshalMessageSlow(b []byte, m protoreflect.Message) error { + md := m.Descriptor() + if messageset.IsMessageSet(md) { + return unmarshalMessageSet(b, m, o) + } + fields := md.Fields() + for len(b) > 0 { + // Parse the tag (field number and wire type). + num, wtyp, tagLen := protowire.ConsumeTag(b) + if tagLen < 0 { + return protowire.ParseError(tagLen) + } + if num > protowire.MaxValidNumber { + return errors.New("invalid field number") + } + + // Find the field descriptor for this field number. + fd := fields.ByNumber(num) + if fd == nil && md.ExtensionRanges().Has(num) { + extType, err := o.Resolver.FindExtensionByNumber(md.FullName(), num) + if err != nil && err != protoregistry.NotFound { + return errors.New("%v: unable to resolve extension %v: %v", md.FullName(), num, err) + } + if extType != nil { + fd = extType.TypeDescriptor() + } + } + var err error + if fd == nil { + err = errUnknown + } else if flags.ProtoLegacy { + if fd.IsWeak() && fd.Message().IsPlaceholder() { + err = errUnknown // weak referent is not linked in + } + } + + // Parse the field value. + var valLen int + switch { + case err != nil: + case fd.IsList(): + valLen, err = o.unmarshalList(b[tagLen:], wtyp, m.Mutable(fd).List(), fd) + case fd.IsMap(): + valLen, err = o.unmarshalMap(b[tagLen:], wtyp, m.Mutable(fd).Map(), fd) + default: + valLen, err = o.unmarshalSingular(b[tagLen:], wtyp, m, fd) + } + if err != nil { + if err != errUnknown { + return err + } + valLen = protowire.ConsumeFieldValue(num, wtyp, b[tagLen:]) + if valLen < 0 { + return protowire.ParseError(valLen) + } + if !o.DiscardUnknown { + m.SetUnknown(append(m.GetUnknown(), b[:tagLen+valLen]...)) + } + } + b = b[tagLen+valLen:] + } + return nil +} + +func (o UnmarshalOptions) unmarshalSingular(b []byte, wtyp protowire.Type, m protoreflect.Message, fd protoreflect.FieldDescriptor) (n int, err error) { + v, n, err := o.unmarshalScalar(b, wtyp, fd) + if err != nil { + return 0, err + } + switch fd.Kind() { + case protoreflect.GroupKind, protoreflect.MessageKind: + m2 := m.Mutable(fd).Message() + if err := o.unmarshalMessage(v.Bytes(), m2); err != nil { + return n, err + } + default: + // Non-message scalars replace the previous value. + m.Set(fd, v) + } + return n, nil +} + +func (o UnmarshalOptions) unmarshalMap(b []byte, wtyp protowire.Type, mapv protoreflect.Map, fd protoreflect.FieldDescriptor) (n int, err error) { + if wtyp != protowire.BytesType { + return 0, errUnknown + } + b, n = protowire.ConsumeBytes(b) + if n < 0 { + return 0, protowire.ParseError(n) + } + var ( + keyField = fd.MapKey() + valField = fd.MapValue() + key protoreflect.Value + val protoreflect.Value + haveKey bool + haveVal bool + ) + switch valField.Kind() { + case protoreflect.GroupKind, protoreflect.MessageKind: + val = mapv.NewValue() + } + // Map entries are represented as a two-element message with fields + // containing the key and value. + for len(b) > 0 { + num, wtyp, n := protowire.ConsumeTag(b) + if n < 0 { + return 0, protowire.ParseError(n) + } + if num > protowire.MaxValidNumber { + return 0, errors.New("invalid field number") + } + b = b[n:] + err = errUnknown + switch num { + case 1: + key, n, err = o.unmarshalScalar(b, wtyp, keyField) + if err != nil { + break + } + haveKey = true + case 2: + var v protoreflect.Value + v, n, err = o.unmarshalScalar(b, wtyp, valField) + if err != nil { + break + } + switch valField.Kind() { + case protoreflect.GroupKind, protoreflect.MessageKind: + if err := o.unmarshalMessage(v.Bytes(), val.Message()); err != nil { + return 0, err + } + default: + val = v + } + haveVal = true + } + if err == errUnknown { + n = protowire.ConsumeFieldValue(num, wtyp, b) + if n < 0 { + return 0, protowire.ParseError(n) + } + } else if err != nil { + return 0, err + } + b = b[n:] + } + // Every map entry should have entries for key and value, but this is not strictly required. + if !haveKey { + key = keyField.Default() + } + if !haveVal { + switch valField.Kind() { + case protoreflect.GroupKind, protoreflect.MessageKind: + default: + val = valField.Default() + } + } + mapv.Set(key.MapKey(), val) + return n, nil +} + +// errUnknown is used internally to indicate fields which should be added +// to the unknown field set of a message. It is never returned from an exported +// function. +var errUnknown = errors.New("BUG: internal error (unknown)") |