diff options
Diffstat (limited to 'vendor/github.com/golang/protobuf/proto/extensions.go')
| -rw-r--r-- | vendor/github.com/golang/protobuf/proto/extensions.go | 224 |
1 files changed, 204 insertions, 20 deletions
diff --git a/vendor/github.com/golang/protobuf/proto/extensions.go b/vendor/github.com/golang/protobuf/proto/extensions.go index 054f4f1..482f3e9 100644 --- a/vendor/github.com/golang/protobuf/proto/extensions.go +++ b/vendor/github.com/golang/protobuf/proto/extensions.go @@ -52,14 +52,99 @@ type ExtensionRange struct { Start, End int32 // both inclusive } -// extendableProto is an interface implemented by any protocol buffer that may be extended. +// extendableProto is an interface implemented by any protocol buffer generated by the current +// proto compiler that may be extended. type extendableProto interface { Message ExtensionRangeArray() []ExtensionRange + extensionsWrite() map[int32]Extension + extensionsRead() (map[int32]Extension, sync.Locker) +} + +// extendableProtoV1 is an interface implemented by a protocol buffer generated by the previous +// version of the proto compiler that may be extended. +type extendableProtoV1 interface { + Message + ExtensionRangeArray() []ExtensionRange ExtensionMap() map[int32]Extension } +// extensionAdapter is a wrapper around extendableProtoV1 that implements extendableProto. +type extensionAdapter struct { + extendableProtoV1 +} + +func (e extensionAdapter) extensionsWrite() map[int32]Extension { + return e.ExtensionMap() +} + +func (e extensionAdapter) extensionsRead() (map[int32]Extension, sync.Locker) { + return e.ExtensionMap(), notLocker{} +} + +// notLocker is a sync.Locker whose Lock and Unlock methods are nops. +type notLocker struct{} + +func (n notLocker) Lock() {} +func (n notLocker) Unlock() {} + +// extendable returns the extendableProto interface for the given generated proto message. +// If the proto message has the old extension format, it returns a wrapper that implements +// the extendableProto interface. +func extendable(p interface{}) (extendableProto, bool) { + if ep, ok := p.(extendableProto); ok { + return ep, ok + } + if ep, ok := p.(extendableProtoV1); ok { + return extensionAdapter{ep}, ok + } + return nil, false +} + +// XXX_InternalExtensions is an internal representation of proto extensions. +// +// Each generated message struct type embeds an anonymous XXX_InternalExtensions field, +// thus gaining the unexported 'extensions' method, which can be called only from the proto package. +// +// The methods of XXX_InternalExtensions are not concurrency safe in general, +// but calls to logically read-only methods such as has and get may be executed concurrently. +type XXX_InternalExtensions struct { + // The struct must be indirect so that if a user inadvertently copies a + // generated message and its embedded XXX_InternalExtensions, they + // avoid the mayhem of a copied mutex. + // + // The mutex serializes all logically read-only operations to p.extensionMap. + // It is up to the client to ensure that write operations to p.extensionMap are + // mutually exclusive with other accesses. + p *struct { + mu sync.Mutex + extensionMap map[int32]Extension + } +} + +// extensionsWrite returns the extension map, creating it on first use. +func (e *XXX_InternalExtensions) extensionsWrite() map[int32]Extension { + if e.p == nil { + e.p = new(struct { + mu sync.Mutex + extensionMap map[int32]Extension + }) + e.p.extensionMap = make(map[int32]Extension) + } + return e.p.extensionMap +} + +// extensionsRead returns the extensions map for read-only use. It may be nil. +// The caller must hold the returned mutex's lock when accessing Elements within the map. +func (e *XXX_InternalExtensions) extensionsRead() (map[int32]Extension, sync.Locker) { + if e.p == nil { + return nil, nil + } + return e.p.extensionMap, &e.p.mu +} + var extendableProtoType = reflect.TypeOf((*extendableProto)(nil)).Elem() +var extendableProtoV1Type = reflect.TypeOf((*extendableProtoV1)(nil)).Elem() // ExtensionDesc represents an extension specification. // Used in generated code from the protocol compiler. @@ -92,8 +177,13 @@ type Extension struct { } // SetRawExtension is for testing only. -func SetRawExtension(base extendableProto, id int32, b []byte) { - base.ExtensionMap()[id] = Extension{enc: b} +func SetRawExtension(base Message, id int32, b []byte) { + epb, ok := extendable(base) + if !ok { + return + } + extmap := epb.extensionsWrite() + extmap[id] = Extension{enc: b} } // isExtensionField returns true iff the given field number is in an extension range. @@ -108,8 +198,12 @@ func isExtensionField(pb extendableProto, field int32) bool { // checkExtensionTypes checks that the given extension is valid for pb. func checkExtensionTypes(pb extendableProto, extension *ExtensionDesc) error { + var pbi interface{} = pb // Check the extended type. - if a, b := reflect.TypeOf(pb), reflect.TypeOf(extension.ExtendedType); a != b { + if ea, ok := pbi.(extensionAdapter); ok { + pbi = ea.extendableProtoV1 + } + if a, b := reflect.TypeOf(pbi), reflect.TypeOf(extension.ExtendedType); a != b { return errors.New("proto: bad extended type; " + b.String() + " does not extend " + a.String()) } // Check the range. @@ -155,8 +249,19 @@ func extensionProperties(ed *ExtensionDesc) *Properties { return prop } -// encodeExtensionMap encodes any unmarshaled (unencoded) extensions in m. -func encodeExtensionMap(m map[int32]Extension) error { +// encode encodes any unmarshaled (unencoded) extensions in e. +func encodeExtensions(e *XXX_InternalExtensions) error { + m, mu := e.extensionsRead() + if m == nil { + return nil // fast path + } + mu.Lock() + defer mu.Unlock() + return encodeExtensionsMap(m) +} + +// encode encodes any unmarshaled (unencoded) extensions in e. +func encodeExtensionsMap(m map[int32]Extension) error { for k, e := range m { if e.value == nil || e.desc == nil { // Extension is only in its encoded form. @@ -184,7 +289,17 @@ func encodeExtensionMap(m map[int32]Extension) error { return nil } -func sizeExtensionMap(m map[int32]Extension) (n int) { +func extensionsSize(e *XXX_InternalExtensions) (n int) { + m, mu := e.extensionsRead() + if m == nil { + return 0 + } + mu.Lock() + defer mu.Unlock() + return extensionsMapSize(m) +} + +func extensionsMapSize(m map[int32]Extension) (n int) { for _, e := range m { if e.value == nil || e.desc == nil { // Extension is only in its encoded form. @@ -209,26 +324,51 @@ func sizeExtensionMap(m map[int32]Extension) (n int) { } // HasExtension returns whether the given extension is present in pb. -func HasExtension(pb extendableProto, extension *ExtensionDesc) bool { +func HasExtension(pb Message, extension *ExtensionDesc) bool { // TODO: Check types, field numbers, etc.? - _, ok := pb.ExtensionMap()[extension.Field] + epb, ok := extendable(pb) + if !ok { + return false + } + extmap, mu := epb.extensionsRead() + if extmap == nil { + return false + } + mu.Lock() + _, ok = extmap[extension.Field] + mu.Unlock() return ok } // ClearExtension removes the given extension from pb. -func ClearExtension(pb extendableProto, extension *ExtensionDesc) { +func ClearExtension(pb Message, extension *ExtensionDesc) { + epb, ok := extendable(pb) + if !ok { + return + } // TODO: Check types, field numbers, etc.? - delete(pb.ExtensionMap(), extension.Field) + extmap := epb.extensionsWrite() + delete(extmap, extension.Field) } // GetExtension parses and returns the given extension of pb. // If the extension is not present and has no default value it returns ErrMissingExtension. -func GetExtension(pb extendableProto, extension *ExtensionDesc) (interface{}, error) { - if err := checkExtensionTypes(pb, extension); err != nil { +func GetExtension(pb Message, extension *ExtensionDesc) (interface{}, error) { + epb, ok := extendable(pb) + if !ok { + return nil, errors.New("proto: not an extendable proto") + } + + if err := checkExtensionTypes(epb, extension); err != nil { return nil, err } - emap := pb.ExtensionMap() + emap, mu := epb.extensionsRead() + if emap == nil { + return defaultExtensionValue(extension) + } + mu.Lock() + defer mu.Unlock() e, ok := emap[extension.Field] if !ok { // defaultExtensionValue returns the default value or @@ -332,10 +472,9 @@ func decodeExtension(b []byte, extension *ExtensionDesc) (interface{}, error) { // GetExtensions returns a slice of the extensions present in pb that are also listed in es. // The returned slice has the same length as es; missing extensions will appear as nil elements. func GetExtensions(pb Message, es []*ExtensionDesc) (extensions []interface{}, err error) { - epb, ok := pb.(extendableProto) + epb, ok := extendable(pb) if !ok { - err = errors.New("proto: not an extendable proto") - return + return nil, errors.New("proto: not an extendable proto") } extensions = make([]interface{}, len(es)) for i, e := range es { @@ -350,9 +489,41 @@ func GetExtensions(pb Message, es []*ExtensionDesc) (extensions []interface{}, e return } +// ExtensionDescs returns a new slice containing pb's extension descriptors, in undefined order. +// For non-registered extensions, ExtensionDescs returns an incomplete descriptor containing +// just the Field field, which defines the extension's field number. +func ExtensionDescs(pb Message) ([]*ExtensionDesc, error) { + epb, ok := extendable(pb) + if !ok { + return nil, fmt.Errorf("proto: %T is not an extendable proto.Message", pb) + } + registeredExtensions := RegisteredExtensions(pb) + + emap, mu := epb.extensionsRead() + mu.Lock() + defer mu.Unlock() + extensions := make([]*ExtensionDesc, 0, len(emap)) + for extid, e := range emap { + desc := e.desc + if desc == nil { + desc = registeredExtensions[extid] + if desc == nil { + desc = &ExtensionDesc{Field: extid} + } + } + + extensions = append(extensions, desc) + } + return extensions, nil +} + // SetExtension sets the specified extension of pb to the specified value. -func SetExtension(pb extendableProto, extension *ExtensionDesc, value interface{}) error { - if err := checkExtensionTypes(pb, extension); err != nil { +func SetExtension(pb Message, extension *ExtensionDesc, value interface{}) error { + epb, ok := extendable(pb) + if !ok { + return errors.New("proto: not an extendable proto") + } + if err := checkExtensionTypes(epb, extension); err != nil { return err } typ := reflect.TypeOf(extension.ExtensionType) @@ -368,10 +539,23 @@ func SetExtension(pb extendableProto, extension *ExtensionDesc, value interface{ return fmt.Errorf("proto: SetExtension called with nil value of type %T", value) } - pb.ExtensionMap()[extension.Field] = Extension{desc: extension, value: value} + extmap := epb.extensionsWrite() + extmap[extension.Field] = Extension{desc: extension, value: value} return nil } +// ClearAllExtensions clears all extensions from pb. +func ClearAllExtensions(pb Message) { + epb, ok := extendable(pb) + if !ok { + return + } + m := epb.extensionsWrite() + for k := range m { + delete(m, k) + } +} + // A global registry of extensions. // The generated code will register the generated descriptors by calling RegisterExtension. |