go/neo/proto: RequestIdentification += DevPath

This corresponds to NEO/py commit 97af23cc (Maximize resiliency by
taking into account the topology of storage nodes).

go/neo/neo.go

-// Copyright (C) 2016-2018  Nexedi SA and Contributors.
+// Copyright (C) 2016-2020  Nexedi SA and Contributors.
 //                          Kirill Smelkov <kirr@nexedi.com>
 //
 // This program is free software: you can Use, Study, Modify and Redistribute
@@ -113,6 +113,7 @@ func (app *NodeApp) Dial(ctx context.Context, peerType proto.NodeType, addr stri
 		UUID:		app.MyInfo.UUID,
 		Address:	app.MyInfo.Addr,
 		ClusterName:	app.ClusterName,
+		DevPath:        nil,                    // XXX stub
 		IdTime:		app.MyInfo.IdTime,	// XXX ok?
 	}
 	accept := &proto.AcceptIdentification{}

go/neo/neo_test.go

@@ -107,6 +107,7 @@ func TestMasterStorage(t0 *testing.T) {
 		UUID:		0,
 		Address:	xnaddr("s:1"),
 		ClusterName:	"abc1",
+		DevPath:        nil,
 		IdTime:		proto.IdTimeNone,
 	}))
 
@@ -208,6 +209,7 @@ func TestMasterStorage(t0 *testing.T) {
 		UUID:		0,
 		Address:	xnaddr(""),
 		ClusterName:	"abc1",
+		DevPath:        nil,
 		IdTime:		proto.IdTimeNone,
 	}))
 
@@ -293,6 +295,7 @@ func TestMasterStorage(t0 *testing.T) {
 		UUID:		proto.UUID(proto.CLIENT, 1),
 		Address:	xnaddr(""),
 		ClusterName:	"abc1",
+		DevPath:        nil,
 		IdTime:		0.02,
 	}))
 

go/neo/proto/proto.go

@@ -372,6 +372,7 @@ type RequestIdentification struct {
 	UUID        NodeUUID
 	Address     Address // where requesting node is also accepting connections
 	ClusterName string
+	DevPath     []string // [] of devid
 	IdTime      IdTime
 }
 

go/neo/proto/proto_test.go

@@ -250,11 +250,12 @@ func TestMsgMarshal(t *testing.T) {
 		},
 
 		// uint32, Address, string, IdTime
-		{&RequestIdentification{CLIENT, 17, Address{"localhost", 7777}, "myname", 0.12345678},
+		{&RequestIdentification{CLIENT, 17, Address{"localhost", 7777}, "myname", []string{"room1", "rack234"}, 0.12345678},
 
 			u8(2) + u32(17) + u32(9) +
 			"localhost" + u16(7777) +
 			u32(6) + "myname" +
+			u32(2) + u32(5)+"room1" + u32(7)+"rack234" +
 			hex("3fbf9add1091c895"),
 		},
 

go/neo/proto/zproto-marshal.go

@@ -65,7 +65,12 @@ func (*RequestIdentification) NEOMsgCode() uint16 {
 }
 
 func (p *RequestIdentification) NEOMsgEncodedLen() int {
-	return 9 + p.Address.neoEncodedLen() + len(p.ClusterName) + p.IdTime.neoEncodedLen()
+	var size int
+	for i := 0; i < len(p.DevPath); i++ {
+		a := &p.DevPath[i]
+		size += len((*a))
+	}
+	return 13 + p.Address.neoEncodedLen() + len(p.ClusterName) + len(p.DevPath)*4 + p.IdTime.neoEncodedLen() + size
 }
 
 func (p *RequestIdentification) NEOMsgEncode(data []byte) {
@@ -82,6 +87,22 @@ func (p *RequestIdentification) NEOMsgEncode(data []byte) {
 		copy(data, p.ClusterName)
 		data = data[l:]
 	}
+	{
+		l := uint32(len(p.DevPath))
+		binary.BigEndian.PutUint32(data[0:], l)
+		data = data[4:]
+		for i := 0; uint32(i) < l; i++ {
+			a := &p.DevPath[i]
+			{
+				l := uint32(len((*a)))
+				binary.BigEndian.PutUint32(data[0:], l)
+				data = data[4:]
+				copy(data, (*a))
+				data = data[l:]
+			}
+			data = data[0:]
+		}
+	}
 	{
 		n := p.IdTime.neoEncode(data[0:])
 		data = data[0+n:]
@@ -110,13 +131,35 @@ func (p *RequestIdentification) NEOMsgDecode(data []byte) (int, error) {
 	{
 		l := binary.BigEndian.Uint32(data[0 : 0+4])
 		data = data[4:]
-		if uint64(len(data)) < uint64(l) {
+		if uint64(len(data)) < 4+uint64(l) {
 			goto overflow
 		}
-		nread += uint64(l)
+		nread += 4 + uint64(l)
 		p.ClusterName = string(data[:l])
 		data = data[l:]
 	}
+	{
+		l := binary.BigEndian.Uint32(data[0 : 0+4])
+		data = data[4:]
+		p.DevPath = make([]string, l)
+		for i := 0; uint32(i) < l; i++ {
+			a := &p.DevPath[i]
+			if len(data) < 4 {
+				goto overflow
+			}
+			{
+				l := binary.BigEndian.Uint32(data[0 : 0+4])
+				data = data[4:]
+				if uint64(len(data)) < uint64(l) {
+					goto overflow
+				}
+				nread += uint64(l)
+				(*a) = string(data[:l])
+				data = data[l:]
+			}
+		}
+		nread += uint64(l) * 4
+	}
 	{
 		n, ok := p.IdTime.neoDecode(data)
 		if !ok {