verification of pending data after run starter

src/netius/base/conn.py

@@ -693,6 +693,9 @@ def is_exhausted(self):
     def is_restored(self):
         return self.pending_s <= self.min_pending
 
+    def is_pending_data(self):
+        return self.restored_s > 0
+
     def _send(self):
         # sets the write ready flag so that any further request to
         # write operation will be immediately performed

src/netius/base/server.py

@@ -920,6 +920,11 @@ def on_socket_c(self, socket_c, address):
         try: connection.run_starter()
         except: connection.close(); raise
 
+        # in case there's extraneous data pending to be read from the
+        # current connection's internal receive buffer it must be properly
+        # handled on the risk of blocking the newly created connection
+        if connection.is_pending_data(): self.on_read(connection.socket)
+
     def on_socket_d(self, socket_c):
         connection = self.connections_m.get(socket_c, None)
         if not connection: return