From 5fff605ff68741482d7fff992343eaccb383115f Mon Sep 17 00:00:00 2001
From: li_yunqing <liyunqing@kylinos.cn>
Date: Fri, 22 Mar 2024 15:47:19 +0800
Subject: [PATCH] fix tcp recv does not return pkg when ring buffer is empty

---
 src/lstack/core/lstack_lwip.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/lstack/core/lstack_lwip.c b/src/lstack/core/lstack_lwip.c
index a604a62..51238ba 100644
--- a/src/lstack/core/lstack_lwip.c
+++ b/src/lstack/core/lstack_lwip.c
@@ -925,7 +925,9 @@ static ssize_t recv_ring_tcp_read(struct lwip_sock *sock, void *buf, size_t len,
     }
 
     while (recv_left > 0) {
-        if (recv_ring_get_one(sock, noblock, &pbuf) != 0)  {
+        if (recv_ring_get_one(sock, noblock | recvd, &pbuf) != 0) {
+            /* When the buffer is empty, it will be returned directly
+            if in non-blocking mode or if data has already been received */
             break;
         }
 
-- 
2.33.0