From 1ed821e28d19f58a44720761e1675cc324c2f458 Mon Sep 17 00:00:00 2001
From: antirez <antirez@gmail.com>
Date: Mon, 5 Nov 2018 13:16:00 +0100
Subject: [PATCH] Fix XCLAIM missing entry bug.

This bug had a double effect:

1. Sometimes entries may not be emitted, producing broken protocol where
the array length was greater than the emitted entires, blocking the
client waiting for more data.

2. Some other time the right entry was claimed, but a wrong entry was
returned to the client.

This fix should correct both the instances.
---
 src/t_stream.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/src/t_stream.c b/src/t_stream.c
index 2acb9c12..55c979ad 100644
--- a/src/t_stream.c
+++ b/src/t_stream.c
@@ -2278,8 +2278,9 @@ void xclaimCommand(client *c) {
             if (justid) {
                 addReplyStreamID(c,&id);
             } else {
-                streamReplyWithRange(c,o->ptr,&id,NULL,1,0,NULL,NULL,
-                                     STREAM_RWR_RAWENTRIES,NULL);
+                size_t emitted = streamReplyWithRange(c,o->ptr,&id,&id,1,0,
+                                    NULL,NULL,STREAM_RWR_RAWENTRIES,NULL);
+                if (!emitted) addReply(c,shared.nullbulk);
             }
             arraylen++;