From 640196c5b3c5df1f7e4cb50ba5f494586ddbf5b5 Mon Sep 17 00:00:00 2001
From: fujr <fjrcn@outlook.com>
Date: Mon, 28 Oct 2024 12:15:01 +0800
Subject: [PATCH] fix error json format when recv sms is empty

---
 application/tom_modem/src/utils.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/application/tom_modem/src/utils.c b/application/tom_modem/src/utils.c
index 41bf5eb..d33daa7 100644
--- a/application/tom_modem/src/utils.c
+++ b/application/tom_modem/src/utils.c
@@ -744,7 +744,12 @@ int display_sms_in_json(SMS_T **sms,int num)
             offset += sprintf(msg_json + offset, "{\"index\":%d,\"sender\":\"%s\",\"timestamp\":%d,\"content\":\"%s\"},",
                           sms[i]->sms_index, sms[i]->sender, sms[i]->timestamp, escaped_text);
     }
-    offset--;
+    
+    //if not empty msg_json,remove the last ','
+    if (offset > 10)
+    {
+        offset--;
+    }
     offset += sprintf(msg_json + offset, "]}");
     user_msg("%s\n", msg_json);
     return 0;