From 2a938d96aec62603dcb548834676ae2c71ae8be2 Mon Sep 17 00:00:00 2001
From: Pedro Calado <pdcalado@gmail.com>
Date: Thu, 29 Oct 2020 14:20:38 +0000
Subject: [PATCH] fix(server): reschedule keep alive interval timer once a pong
 is received

`KeepAliveState` did not transition from `PingSent` to `Scheduled` after
a pong was received. This prevented more than one ping to be sent by the
server. This fix checks if `ping_sent_at` has already been cleared by
`Ponger::poll` when `KeepAliveState::PingSent` state is active.

Fixes #2310
---
 src/proto/h2/ping.rs | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/src/proto/h2/ping.rs b/src/proto/h2/ping.rs
index c4fe2dd15c..54dd6442a8 100644
--- a/src/proto/h2/ping.rs
+++ b/src/proto/h2/ping.rs
@@ -442,7 +442,16 @@ impl KeepAlive {
                 let interval = shared.last_read_at() + self.interval;
                 self.timer.reset(interval);
             }
-            KeepAliveState::Scheduled | KeepAliveState::PingSent => (),
+            KeepAliveState::PingSent => {
+                if shared.is_ping_sent() {
+                    return;
+                }
+
+                self.state = KeepAliveState::Scheduled;
+                let interval = shared.last_read_at() + self.interval;
+                self.timer.reset(interval);
+            }
+            KeepAliveState::Scheduled => (),
         }
     }