From 29d644e9d3fbd3fa2db224825370ca8323291fe7 Mon Sep 17 00:00:00 2001
From: Tom Ritchford <tom@swirly.com>
Date: Mon, 20 Apr 2015 15:37:39 -0400
Subject: [PATCH] Fix WebSockets treatment of ping timer:

This solves a problem that caused a hang on shutdown related to
the lifetime of the ping timer completion handlers used in WebSockets.

* Turn the ping timer back on
* Use std::weak_ptr for WebSockets timer callbacks.
* Disable WebSocket pings if frequency in the .cfg is non-positive.
---
 src/ripple/websocket/Connection.h    |  1 -
 src/ripple/websocket/Handler.h       |  1 +
 src/ripple/websocket/WebSocket02.cpp | 21 +++++++++++----------
 src/ripple/websocket/WebSocket04.cpp | 14 +++++++++-----
 4 files changed, 21 insertions(+), 16 deletions(-)

diff --git a/src/ripple/websocket/Connection.h b/src/ripple/websocket/Connection.h
index 0346ace01..390bd7b78 100644
--- a/src/ripple/websocket/Connection.h
+++ b/src/ripple/websocket/Connection.h
@@ -139,7 +139,6 @@ ConnectionImpl <WebSocket>::ConnectionImpl (
         , m_handler (handler)
         , m_connection (cpConnection)
 {
-    setPingTimer ();
 }
 
 template <class WebSocket>
diff --git a/src/ripple/websocket/Handler.h b/src/ripple/websocket/Handler.h
index d18cfb37b..687a73976 100644
--- a/src/ripple/websocket/Handler.h
+++ b/src/ripple/websocket/Handler.h
@@ -208,6 +208,7 @@ public:
                 cpClient,
                 makeBeastEndpoint (remoteEndpoint),
                 WebSocket::getStrand (*cpClient).get_io_service ());
+            connection->setPingTimer ();
             auto result = mMap.emplace (cpClient, std::move (connection));
 
             assert (result.second);
diff --git a/src/ripple/websocket/WebSocket02.cpp b/src/ripple/websocket/WebSocket02.cpp
index da9c20b0b..b194a467b 100644
--- a/src/ripple/websocket/WebSocket02.cpp
+++ b/src/ripple/websocket/WebSocket02.cpp
@@ -20,6 +20,7 @@
 #include <ripple/websocket/WebSocket02.h>
 #include <ripple/websocket/Handler.h>
 #include <ripple/websocket/Server.h>
+#include <beast/weak_fn.h>
 
 // This file contains websocket::WebSocket02 implementations for the WebSocket
 // generic functions as well as methods on Server and ConnectionImpl.
@@ -72,22 +73,22 @@ boost::asio::io_service::strand& WebSocket02::getStrand (Connection& con)
 template <>
 void ConnectionImpl <WebSocket02>::setPingTimer ()
 {
-#if 0
+    auto freq = getConfig ().WEBSOCKET_PING_FREQ;
+    if (freq <= 0)
+        return;
     connection_ptr ptr = m_connection.lock ();
 
     if (ptr)
     {
-        this->m_pingTimer.expires_from_now (boost::posix_time::seconds
-            (getConfig ().WEBSOCKET_PING_FREQ));
+        this->m_pingTimer.expires_from_now (boost::posix_time::seconds (freq));
 
-        auto pt = [this] (boost::system::error_code const& e)
-        {
-            this->pingTimer (e);
-        };
-
-        this->m_pingTimer.async_wait (ptr->get_strand ().wrap (pt));
+        this->m_pingTimer.async_wait (
+            ptr->get_strand ().wrap (
+                std::bind (
+                    beast::weak_fn (&ConnectionImpl <WebSocket02>::pingTimer,
+                                    shared_from_this()),
+                    beast::asio::placeholders::error)));
     }
-#endif
 }
 
 template <>
diff --git a/src/ripple/websocket/WebSocket04.cpp b/src/ripple/websocket/WebSocket04.cpp
index cce1b4b2f..287f5a9f5 100644
--- a/src/ripple/websocket/WebSocket04.cpp
+++ b/src/ripple/websocket/WebSocket04.cpp
@@ -22,6 +22,7 @@
 #include <ripple/websocket/Server.h>
 
 #include <boost/make_shared.hpp>
+#include <beast/weak_fn.h>
 
 namespace ripple {
 namespace websocket {
@@ -114,16 +115,19 @@ EndpointPtr04  WebSocket04::makeEndpoint (HandlerPtr&& handler)
 template <>
 void ConnectionImpl <WebSocket04>::setPingTimer ()
 {
+    auto freq = getConfig ().WEBSOCKET_PING_FREQ;
+    if (freq <= 0)
+        return;
     if (auto con = m_connection.lock ())
     {
-        auto t = boost::posix_time::seconds (getConfig ().WEBSOCKET_PING_FREQ);
+        auto t = boost::posix_time::seconds (freq);
         auto ms = t.total_milliseconds();
         con->set_timer (
             ms,
-            [this] (WebSocket04::ErrorCode const& e)
-            {
-                this->pingTimer (e);
-            });
+            std::bind (
+                beast::weak_fn (&ConnectionImpl <WebSocket04>::pingTimer,
+                                shared_from_this()),
+                beast::asio::placeholders::error));
     }
 }