From 26c93af5652a39b773240e7f4fd452263ae38104 Mon Sep 17 00:00:00 2001
From: Kovid Goyal <kovid@kovidgoyal.net>
Date: Tue, 4 Jul 2023 04:56:30 +0530
Subject: [PATCH] ...

---
 tools/rsync/algorithm.go | 2 ++
 tools/rsync/api.go       | 4 +++-
 tools/rsync/api_test.go  | 2 +-
 3 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/tools/rsync/algorithm.go b/tools/rsync/algorithm.go
index c02530f96..d9a133f34 100644
--- a/tools/rsync/algorithm.go
+++ b/tools/rsync/algorithm.go
@@ -82,6 +82,7 @@ func (self *Operation) Unserialize(data []byte) (n int, err error) {
 			return -1, io.ErrShortBuffer
 		}
 		self.BlockIndex = bin.Uint64(data[1:])
+		self.Data = nil
 	case OpBlockRange:
 		n = 13
 		if len(data) < n {
@@ -89,6 +90,7 @@ func (self *Operation) Unserialize(data []byte) (n int, err error) {
 		}
 		self.BlockIndex = bin.Uint64(data[1:])
 		self.BlockIndexEnd = self.BlockIndex + uint64(bin.Uint32(data[9:]))
+		self.Data = nil
 	case OpHash:
 		n = 3
 		if len(data) < n {
diff --git a/tools/rsync/api.go b/tools/rsync/api.go
index a85b36abd..30e20853d 100644
--- a/tools/rsync/api.go
+++ b/tools/rsync/api.go
@@ -116,7 +116,9 @@ func (self *Patcher) update_delta(data []byte) (consumed int, err error) {
 			if err = self.rsync.ApplyDelta(self.delta_output, self.delta_input, op); err != nil {
 				return
 			}
-			self.total_data_in_delta += len(op.Data)
+			if op.Type == OpData {
+				self.total_data_in_delta += len(op.Data)
+			}
 		} else {
 			if n < 0 {
 				return consumed, nil
diff --git a/tools/rsync/api_test.go b/tools/rsync/api_test.go
index 2fc0d9d11..00e4645ed 100644
--- a/tools/rsync/api_test.go
+++ b/tools/rsync/api_test.go
@@ -24,7 +24,7 @@ func TestRsyncRoundtrip(t *testing.T) {
 
 	random_patch := func(data []byte) (size int) {
 		if offset := random.Int(len(data)); offset < len(data) {
-			max_size := utils.Min(256, len(data)-offset)
+			max_size := utils.Min(257, len(data)-offset)
 			if size = random.Int(max_size); size > 0 {
 				total_patch_size += size
 				random.Bytes(data[offset : offset+size])