Switch to github.com/golang/dep for vendoring

Signed-off-by: Mrunal Patel <mrunalp@gmail.com>

vendor/github.com/gogo/protobuf/proto/extensions.go

@@ -52,23 +52,112 @@ 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)
 }
 
-type extensionsMap interface {
-	extendableProto
+// 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
 }
 
 type extensionsBytes interface {
-	extendableProto
+	Message
+	ExtensionRangeArray() []ExtensionRange
 	GetExtensions() *[]byte
 }
 
+// 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
+}
+
+type extensionRange interface {
+	Message
+	ExtensionRangeArray() []ExtensionRange
+}
+
 var extendableProtoType = reflect.TypeOf((*extendableProto)(nil)).Elem()
+var extendableProtoV1Type = reflect.TypeOf((*extendableProtoV1)(nil)).Elem()
+var extendableBytesType = reflect.TypeOf((*extensionsBytes)(nil)).Elem()
+var extensionRangeType = reflect.TypeOf((*extensionRange)(nil)).Elem()
 
 // ExtensionDesc represents an extension specification.
 // Used in generated code from the protocol compiler.
@@ -101,20 +190,23 @@ type Extension struct {
 }
 
 // SetRawExtension is for testing only.
-func SetRawExtension(base extendableProto, id int32, b []byte) {
-	if ebase, ok := base.(extensionsMap); ok {
-		ebase.ExtensionMap()[id] = Extension{enc: b}
-	} else if ebase, ok := base.(extensionsBytes); ok {
+func SetRawExtension(base Message, id int32, b []byte) {
+	if ebase, ok := base.(extensionsBytes); ok {
 		clearExtension(base, id)
 		ext := ebase.GetExtensions()
 		*ext = append(*ext, b...)
-	} else {
-		panic("unreachable")
+		return
 	}
+	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.
-func isExtensionField(pb extendableProto, field int32) bool {
+func isExtensionField(pb extensionRange, field int32) bool {
 	for _, er := range pb.ExtensionRangeArray() {
 		if er.Start <= field && field <= er.End {
 			return true
@@ -125,8 +217,12 @@ 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.
@@ -172,43 +268,57 @@ 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 {
-		err := encodeExtension(&e)
-		if err != nil {
+		if e.value == nil || e.desc == nil {
+			// Extension is only in its encoded form.
+			continue
+		}
+
+		// We don't skip extensions that have an encoded form set,
+		// because the extension value may have been mutated after
+		// the last time this function was called.
+
+		et := reflect.TypeOf(e.desc.ExtensionType)
+		props := extensionProperties(e.desc)
+
+		p := NewBuffer(nil)
+		// If e.value has type T, the encoder expects a *struct{ X T }.
+		// Pass a *T with a zero field and hope it all works out.
+		x := reflect.New(et)
+		x.Elem().Set(reflect.ValueOf(e.value))
+		if err := props.enc(p, props, toStructPointer(x)); err != nil {
 			return err
 		}
+		e.enc = p.buf
 		m[k] = e
 	}
 	return nil
 }
 
-func encodeExtension(e *Extension) error {
-	if e.value == nil || e.desc == nil {
-		// Extension is only in its encoded form.
-		return nil
+func extensionsSize(e *XXX_InternalExtensions) (n int) {
+	m, mu := e.extensionsRead()
+	if m == nil {
+		return 0
 	}
-	// We don't skip extensions that have an encoded form set,
-	// because the extension value may have been mutated after
-	// the last time this function was called.
-
-	et := reflect.TypeOf(e.desc.ExtensionType)
-	props := extensionProperties(e.desc)
-
-	p := NewBuffer(nil)
-	// If e.value has type T, the encoder expects a *struct{ X T }.
-	// Pass a *T with a zero field and hope it all works out.
-	x := reflect.New(et)
-	x.Elem().Set(reflect.ValueOf(e.value))
-	if err := props.enc(p, props, toStructPointer(x)); err != nil {
-		return err
-	}
-	e.enc = p.buf
-	return nil
+	mu.Lock()
+	defer mu.Unlock()
+	return extensionsMapSize(m)
 }
 
-func sizeExtensionMap(m map[int32]Extension) (n int) {
+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.
@@ -233,12 +343,8 @@ 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 {
-	// TODO: Check types, field numbers, etc.?
-	if epb, doki := pb.(extensionsMap); doki {
-		_, ok := epb.ExtensionMap()[extension.Field]
-		return ok
-	} else if epb, doki := pb.(extensionsBytes); doki {
+func HasExtension(pb Message, extension *ExtensionDesc) bool {
+	if epb, doki := pb.(extensionsBytes); doki {
 		ext := epb.GetExtensions()
 		buf := *ext
 		o := 0
@@ -258,7 +364,19 @@ func HasExtension(pb extendableProto, extension *ExtensionDesc) bool {
 		}
 		return false
 	}
-	panic("unreachable")
+	// TODO: Check types, field numbers, etc.?
+	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
 }
 
 func deleteExtension(pb extensionsBytes, theFieldNum int32, offset int) int {
@@ -281,64 +399,32 @@ func deleteExtension(pb extensionsBytes, theFieldNum int32, offset int) int {
 	return -1
 }
 
-func clearExtension(pb extendableProto, fieldNum int32) {
-	if epb, doki := pb.(extensionsMap); doki {
-		delete(epb.ExtensionMap(), fieldNum)
-	} else if epb, doki := pb.(extensionsBytes); doki {
+// ClearExtension removes the given extension from pb.
+func ClearExtension(pb Message, extension *ExtensionDesc) {
+	clearExtension(pb, extension.Field)
+}
+
+func clearExtension(pb Message, fieldNum int32) {
+	if epb, doki := pb.(extensionsBytes); doki {
 		offset := 0
 		for offset != -1 {
 			offset = deleteExtension(epb, fieldNum, offset)
 		}
-	} else {
-		panic("unreachable")
+		return
+	}
+	epb, ok := extendable(pb)
+	if !ok {
+		return
 	}
-}
-
-// ClearExtension removes the given extension from pb.
-func ClearExtension(pb extendableProto, extension *ExtensionDesc) {
 	// TODO: Check types, field numbers, etc.?
-	clearExtension(pb, extension.Field)
+	extmap := epb.extensionsWrite()
+	delete(extmap, fieldNum)
 }
 
 // GetExtension parses and returns the given extension of pb.
-// If the extension is not present it returns ErrMissingExtension.
-func GetExtension(pb extendableProto, extension *ExtensionDesc) (interface{}, error) {
-	if err := checkExtensionTypes(pb, extension); err != nil {
-		return nil, err
-	}
-
-	if epb, doki := pb.(extensionsMap); doki {
-		emap := epb.ExtensionMap()
-		e, ok := emap[extension.Field]
-		if !ok {
-			// defaultExtensionValue returns the default value or
-			// ErrMissingExtension if there is no default.
-			return defaultExtensionValue(extension)
-		}
-		if e.value != nil {
-			// Already decoded. Check the descriptor, though.
-			if e.desc != extension {
-				// This shouldn't happen. If it does, it means that
-				// GetExtension was called twice with two different
-				// descriptors with the same field number.
-				return nil, errors.New("proto: descriptor conflict")
-			}
-			return e.value, nil
-		}
-
-		v, err := decodeExtension(e.enc, extension)
-		if err != nil {
-			return nil, err
-		}
-
-		// Remember the decoded version and drop the encoded version.
-		// That way it is safe to mutate what we return.
-		e.value = v
-		e.desc = extension
-		e.enc = nil
-		emap[extension.Field] = e
-		return e.value, nil
-	} else if epb, doki := pb.(extensionsBytes); doki {
+// If the extension is not present and has no default value it returns ErrMissingExtension.
+func GetExtension(pb Message, extension *ExtensionDesc) (interface{}, error) {
+	if epb, doki := pb.(extensionsBytes); doki {
 		ext := epb.GetExtensions()
 		o := 0
 		for o < len(*ext) {
@@ -360,7 +446,50 @@ func GetExtension(pb extendableProto, extension *ExtensionDesc) (interface{}, er
 		}
 		return defaultExtensionValue(extension)
 	}
-	panic("unreachable")
+	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, 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
+		// ErrMissingExtension if there is no default.
+		return defaultExtensionValue(extension)
+	}
+
+	if e.value != nil {
+		// Already decoded. Check the descriptor, though.
+		if e.desc != extension {
+			// This shouldn't happen. If it does, it means that
+			// GetExtension was called twice with two different
+			// descriptors with the same field number.
+			return nil, errors.New("proto: descriptor conflict")
+		}
+		return e.value, nil
+	}
+
+	v, err := decodeExtension(e.enc, extension)
+	if err != nil {
+		return nil, err
+	}
+
+	// Remember the decoded version and drop the encoded version.
+	// That way it is safe to mutate what we return.
+	e.value = v
+	e.desc = extension
+	e.enc = nil
+	emap[extension.Field] = e
+	return e.value, nil
 }
 
 // defaultExtensionValue returns the default value for extension.
@@ -434,14 +563,9 @@ 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)
-	if !ok {
-		err = errors.New("proto: not an extendable proto")
-		return
-	}
 	extensions = make([]interface{}, len(es))
 	for i, e := range es {
-		extensions[i], err = GetExtension(epb, e)
+		extensions[i], err = GetExtension(pb, e)
 		if err == ErrMissingExtension {
 			err = nil
 		}
@@ -452,9 +576,55 @@ 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 {
+	if epb, doki := pb.(extensionsBytes); doki {
+		ClearExtension(pb, extension)
+		ext := epb.GetExtensions()
+		et := reflect.TypeOf(extension.ExtensionType)
+		props := extensionProperties(extension)
+		p := NewBuffer(nil)
+		x := reflect.New(et)
+		x.Elem().Set(reflect.ValueOf(value))
+		if err := props.enc(p, props, toStructPointer(x)); err != nil {
+			return err
+		}
+		*ext = append(*ext, p.buf...)
+		return nil
+	}
+	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)
@@ -469,26 +639,27 @@ func SetExtension(pb extendableProto, extension *ExtensionDesc, value interface{
 	if reflect.ValueOf(value).IsNil() {
 		return fmt.Errorf("proto: SetExtension called with nil value of type %T", value)
 	}
-	return setExtension(pb, extension, value)
+
+	extmap := epb.extensionsWrite()
+	extmap[extension.Field] = Extension{desc: extension, value: value}
+	return nil
 }
 
-func setExtension(pb extendableProto, extension *ExtensionDesc, value interface{}) error {
-	if epb, doki := pb.(extensionsMap); doki {
-		epb.ExtensionMap()[extension.Field] = Extension{desc: extension, value: value}
-	} else if epb, doki := pb.(extensionsBytes); doki {
-		ClearExtension(pb, extension)
+// ClearAllExtensions clears all extensions from pb.
+func ClearAllExtensions(pb Message) {
+	if epb, doki := pb.(extensionsBytes); doki {
 		ext := epb.GetExtensions()
-		et := reflect.TypeOf(extension.ExtensionType)
-		props := extensionProperties(extension)
-		p := NewBuffer(nil)
-		x := reflect.New(et)
-		x.Elem().Set(reflect.ValueOf(value))
-		if err := props.enc(p, props, toStructPointer(x)); err != nil {
-			return err
-		}
-		*ext = append(*ext, p.buf...)
+		*ext = []byte{}
+		return
+	}
+	epb, ok := extendable(pb)
+	if !ok {
+		return
+	}
+	m := epb.extensionsWrite()
+	for k := range m {
+		delete(m, k)
 	}
-	return nil
 }
 
 // A global registry of extensions.