From 10c014bf98fbc1d87aefda93332223d90f08953f Mon Sep 17 00:00:00 2001
From: Benjamin Sergeant <bsergean@gmail.com>
Date: Fri, 19 Jun 2020 00:11:06 -0700
Subject: [PATCH] (http client) fix deadlock when following redirects

---
 docs/CHANGELOG.md                | 4 ++++
 ixwebsocket/IXHttpClient.cpp     | 2 +-
 ixwebsocket/IXHttpClient.h       | 4 +++-
 ixwebsocket/IXWebSocketVersion.h | 2 +-
 4 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/docs/CHANGELOG.md b/docs/CHANGELOG.md
index 59e68e03..537b9987 100644
--- a/docs/CHANGELOG.md
+++ b/docs/CHANGELOG.md
@@ -1,6 +1,10 @@
 # Changelog
 All changes to this project will be documented in this file.
 
+## [9.7.9] - 2020-06-18
+
+(http client) fix deadlock when following redirects
+
 ## [9.7.8] - 2020-06-18
 
 (cobra metrics to statsd bot) send info about net requests
diff --git a/ixwebsocket/IXHttpClient.cpp b/ixwebsocket/IXHttpClient.cpp
index ef8da7da..49da10da 100644
--- a/ixwebsocket/IXHttpClient.cpp
+++ b/ixwebsocket/IXHttpClient.cpp
@@ -127,7 +127,7 @@ namespace ix
     {
         // We only have one socket connection, so we cannot
         // make multiple requests concurrently.
-        std::lock_guard<std::mutex> lock(_mutex);
+        std::lock_guard<std::recursive_mutex> lock(_mutex);
 
         uint64_t uploadSize = 0;
         uint64_t downloadSize = 0;
diff --git a/ixwebsocket/IXHttpClient.h b/ixwebsocket/IXHttpClient.h
index f591b1e9..828a5fe7 100644
--- a/ixwebsocket/IXHttpClient.h
+++ b/ixwebsocket/IXHttpClient.h
@@ -103,7 +103,9 @@ namespace ix
         std::thread _thread;
 
         std::unique_ptr<Socket> _socket;
-        std::mutex _mutex; // to protect accessing the _socket (only one socket per client)
+        std::recursive_mutex _mutex; // to protect accessing the _socket (only one socket per client)
+                                     // the mutex needs to be recursive as this function might
+                                     // be called recursively to follow HTTP redirections
 
         SocketTLSOptions _tlsOptions;
 
diff --git a/ixwebsocket/IXWebSocketVersion.h b/ixwebsocket/IXWebSocketVersion.h
index 6db51798..21215abf 100644
--- a/ixwebsocket/IXWebSocketVersion.h
+++ b/ixwebsocket/IXWebSocketVersion.h
@@ -6,4 +6,4 @@
 
 #pragma once
 
-#define IX_WEBSOCKET_VERSION "9.7.8"
+#define IX_WEBSOCKET_VERSION "9.7.9"