From 2a7b43d853fb5a858fab7854f6bd5d0cc823f494 Mon Sep 17 00:00:00 2001
From: Alex Stokes <r.alex.stokes@gmail.com>
Date: Thu, 7 Nov 2019 20:57:55 -0800
Subject: [PATCH] bugfix: return empty bytes immediately if read length is 0

---
 libp2p/security/secio/transport.py | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/libp2p/security/secio/transport.py b/libp2p/security/secio/transport.py
index 6a4c867..cf807bf 100644
--- a/libp2p/security/secio/transport.py
+++ b/libp2p/security/secio/transport.py
@@ -111,6 +111,9 @@ class SecureSession(BaseSession):
         self.high_watermark = len(msg)
 
     async def read(self, n: int = -1) -> bytes:
+        if n == 0:
+            return bytes()
+
         data_from_buffer = self._drain(n)
         if len(data_from_buffer) > 0:
             return data_from_buffer