From db0880bd2675cfb097d15147940a32e272db1c89 Mon Sep 17 00:00:00 2001
From: qiyongzhong0 <917768104@qq.com>
Date: Mon, 2 Nov 2020 17:43:23 +0800
Subject: [PATCH] fix at_client, avoid creating the same client repeatedly and
 prevent working exceptions and memory leaks.

---
 components/net/at/src/at_client.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/components/net/at/src/at_client.c b/components/net/at/src/at_client.c
index ba4009738d..788549392d 100644
--- a/components/net/at/src/at_client.c
+++ b/components/net/at/src/at_client.c
@@ -917,6 +917,11 @@ int at_client_init(const char *dev_name,  rt_size_t recv_bufsz)
     RT_ASSERT(dev_name);
     RT_ASSERT(recv_bufsz > 0);
 
+    if (at_client_get(dev_name) != RT_NULL)
+    {
+        return result;
+    }
+
     for (idx = 0; idx < AT_CLIENT_NUM_MAX && at_client_table[idx].device; idx++);
 
     if (idx >= AT_CLIENT_NUM_MAX)