tlv: DecodingBuffer.IterElements

ndn/data.go

@@ -231,7 +231,7 @@ func (data Data) Field() tlv.Field {
 func (data *Data) UnmarshalBinary(value []byte) (e error) {
 	*data = Data{}
 	d := tlv.DecodingBuffer(value)
-	for _, de := range d.Elements() {
+	for de := range d.IterElements() {
 		switch de.Type {
 		case an.TtName:
 			if e = de.UnmarshalValue(&data.Name); e != nil {
@@ -263,7 +263,7 @@ func (data *Data) UnmarshalBinary(value []byte) (e error) {
 
 func (data *Data) decodeMetaInfo(value []byte) (e error) {
 	d := tlv.DecodingBuffer(value)
-	for _, de := range d.Elements() {
+	for de := range d.IterElements() {
 		switch de.Type {
 		case an.TtContentType:
 			if data.ContentType = ContentType(de.UnmarshalNNI(math.MaxUint64, &e, tlv.ErrRange)); e != nil {

ndn/interest.go

@@ -217,7 +217,7 @@ func (interest *Interest) UnmarshalBinary(wire []byte) (e error) {
 	*interest = Interest{}
 	d := tlv.DecodingBuffer(wire)
 	var paramsPortion []byte
-	for _, de := range d.Elements() {
+	for de := range d.IterElements() {
 		switch de.Type {
 		case an.TtName:
 			if e = de.UnmarshalValue(&interest.Name); e != nil {
@@ -332,7 +332,7 @@ func (fh ForwardingHint) Field() tlv.Field {
 // UnmarshalBinary decodes from TLV-VALUE.
 func (fh *ForwardingHint) UnmarshalBinary(wire []byte) error {
 	d := tlv.DecodingBuffer(wire)
-	for _, de := range d.Elements() {
+	for de := range d.IterElements() {
 		switch de.Type {
 		case an.TtName:
 			var del Name

ndn/keychain/cert.go

@@ -202,7 +202,7 @@ func (vp ValidityPeriod) Field() tlv.Field {
 func (vp *ValidityPeriod) UnmarshalBinary(wire []byte) (e error) {
 	*vp = ValidityPeriod{}
 	d := tlv.DecodingBuffer(wire)
-	for _, de := range d.Elements() {
+	for de := range d.IterElements() {
 		switch de.Type {
 		case an.TtNotBefore:
 			vp.NotBefore = parseValidityPeriodTime(de.Value)

ndn/keychain/safebag.go

@@ -41,7 +41,7 @@ func ImportSafeBag(wire, passphrase []byte) (pvt PrivateKey, cert *Certificate,
 
 	var pvtKey any
 	d := tlv.DecodingBuffer(safeBagTLV.Value)
-	for _, de := range d.Elements() {
+	for de := range d.IterElements() {
 		switch de.Type {
 		case an.TtData:
 			var data ndn.Data

ndn/packet.go

@@ -129,7 +129,7 @@ func (pkt *Packet) UnmarshalTLV(typ uint32, value []byte) (e error) {
 func (pkt *Packet) decodeValue(value []byte) (e error) {
 	fragment := LpFragment{FragCount: 1}
 	d := tlv.DecodingBuffer(value)
-	for _, de := range d.Elements() {
+	for de := range d.IterElements() {
 		switch de.Type {
 		case an.TtLpSeqNum:
 			if de.Length() != 8 {

ndn/rdr/rdr.go

@@ -81,7 +81,7 @@ func (m *Metadata) Decode(value []byte, extensions MetadataDecoderMap) error {
 	*m = Metadata{}
 	d := tlv.DecodingBuffer(value)
 	hasName := false
-	for _, de := range d.Elements() {
+	for de := range d.IterElements() {
 		var f MetadataFieldDecoder
 		if de.Type == an.TtName && !hasName {
 			f = m.decodeName

ndn/sig-info.go

@@ -42,7 +42,7 @@ func (kl KeyLocator) Field() tlv.Field {
 func (kl *KeyLocator) UnmarshalBinary(wire []byte) error {
 	*kl = KeyLocator{}
 	d := tlv.DecodingBuffer(wire)
-	for _, de := range d.Elements() {
+	for de := range d.IterElements() {
 		switch de.Type {
 		case an.TtName:
 			if e := de.UnmarshalValue(&kl.Name); e != nil {
@@ -102,7 +102,7 @@ func (si *SigInfo) FindExtension(typ uint32) *tlv.Element {
 func (si *SigInfo) UnmarshalBinary(wire []byte) (e error) {
 	*si = SigInfo{}
 	d := tlv.DecodingBuffer(wire)
-	for _, de := range d.Elements() {
+	for de := range d.IterElements() {
 		switch de.Type {
 		case an.TtSigType:
 			if si.Type = uint32(de.UnmarshalNNI(math.MaxUint32, &e, ErrSigType)); e != nil {

ndn/tlv/decode.go

@@ -2,6 +2,8 @@ package tlv
 
 import (
 	"encoding"
+	"iter"
+	"slices"
 )
 
 // Unmarshaler is the interface implemented by an object that can decode an TLV element representation of itself.
@@ -58,17 +60,26 @@ func (d *DecodingBuffer) Element() (de DecodingElement, e error) {
 	return de, nil
 }
 
-// Elements recognizes TLV elements from the buffer.
-// Bytes that cannot be recognized as TLV elements are left in the decoder.
-func (d *DecodingBuffer) Elements() (list []DecodingElement) {
-	for {
-		de, e := d.Element()
-		if e != nil {
-			break
+// IterElements returns an iterator that recognizes TLV elements from the buffer.
+//
+// Iteration stops when no more TLV elements can be recognized.
+// Remaining bytes are left in the decoder.
+func (d *DecodingBuffer) IterElements() iter.Seq[DecodingElement] {
+	return func(yield func(DecodingElement) bool) {
+		for {
+			de, e := d.Element()
+			if e != nil || !yield(de) {
+				return
+			}
 		}
-		list = append(list, de)
 	}
-	return list
+}
+
+// Elements recognizes TLV elements from the buffer.
+//
+// Remaining bytes that cannot be recognized as TLV elements are left in the decoder.
+func (d *DecodingBuffer) Elements() []DecodingElement {
+	return slices.Collect(d.IterElements())
 }
 
 // DecodingElement represents an TLV element during decoding.

ndni/datagen.go

@@ -59,7 +59,7 @@ func (gen *DataGen) Init(m *pktmbuf.Packet, args ...any) {
 	}
 
 	d := tlv.DecodingBuffer(wire)
-	for _, de := range d.Elements() {
+	for de := range d.IterElements() {
 		switch de.Type {
 		case an.TtName:
 			gen.suffix = C.LName{

ndni/interest-template.go

@@ -43,7 +43,7 @@ func (tpl *InterestTemplate) Init(args ...any) {
 	*tpl = InterestTemplate{}
 
 	d := tlv.DecodingBuffer(wire)
-	for _, de := range d.Elements() {
+	for de := range d.IterElements() {
 		switch de.Type {
 		case an.TtName:
 			tpl.prefixL = C.uint16_t(copy(cptr.AsByteSlice(tpl.prefixV[:]), de.Value))