[PATCH net-next v2 7/8] tools/net/ynl: Add retry limit for async notification

[Xiao Liang <shaw.leon@gmail.com>]

Since commit 1bf70e6c3a53 ("tools/net/ynl: improve async notification
handling"), check_ntf() would block indefinitely if there's no messages.
In some cases we want to set a limit on waiting time. This patch adds
max_reties parameter check_ntf(), and makes it stop when no message is
recievied in that number of consecutive retries.

Signed-off-by: Xiao Liang <shaw.leon@gmail.com>
---
 tools/net/ynl/lib/ynl.py | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/tools/net/ynl/lib/ynl.py b/tools/net/ynl/lib/ynl.py
index 92f85698c50e..dff5166a4650 100644
--- a/tools/net/ynl/lib/ynl.py
+++ b/tools/net/ynl/lib/ynl.py
@@ -907,7 +907,8 @@ class YnlFamily(SpecFamily):
         msg['msg'] = attrs
         self.async_msg_queue.put(msg)
 
-    def check_ntf(self, interval=0.1):
+    def check_ntf(self, interval=0.1, max_retries=None):
+        retry = 0
         while True:
             try:
                 reply = self.sock.recv(self._recv_size, socket.MSG_DONTWAIT)
@@ -933,7 +934,11 @@ class YnlFamily(SpecFamily):
 
             try:
                 yield self.async_msg_queue.get_nowait()
+                retry = 0
             except queue.Empty:
+                retry += 1
+                if max_retries is not None and retry > max_retries:
+                    return
                 try:
                     time.sleep(interval)
                 except KeyboardInterrupt:
-- 
2.47.0