From bf3ffb4225f959f92b2ec5cd01ed06cfb2d7a6f6 Mon Sep 17 00:00:00 2001
From: Ivan Santiago Paunovic <ivanpauno@ekumenlabs.com>
Date: Wed, 7 Apr 2021 03:03:40 -0300
Subject: [PATCH] Protect DepthCameraPlugin globals with a mutex (#2949)

Signed-off-by: Ivan Santiago Paunovic <ivanpauno@ekumenlabs.com>
---
 plugins/DepthCameraPlugin.cc | 19 ++++++++++---------
 1 file changed, 10 insertions(+), 9 deletions(-)

diff --git a/plugins/DepthCameraPlugin.cc b/plugins/DepthCameraPlugin.cc
index aa71dd8429..a42cec6dbb 100644
--- a/plugins/DepthCameraPlugin.cc
+++ b/plugins/DepthCameraPlugin.cc
@@ -16,16 +16,20 @@
 */
 
 #include <functional>
+#include <mutex>
+#include <unordered_map>
 
 #include "plugins/DepthCameraPlugin.hh"
 
 using namespace gazebo;
 GZ_REGISTER_SENSOR_PLUGIN(DepthCameraPlugin)
 
+std::mutex global_maps_mutex;
+
 // Added this map to avoid breaking the ABI
-static std::map<DepthCameraPlugin*, event::ConnectionPtr>
+static std::unordered_map<DepthCameraPlugin*, event::ConnectionPtr>
                                                 connection_reflectance_map;
-static std::map<DepthCameraPlugin*, event::ConnectionPtr>
+static std::unordered_map<DepthCameraPlugin*, event::ConnectionPtr>
                                                 connection_normals_map;
 /////////////////////////////////////////////////
 DepthCameraPlugin::DepthCameraPlugin()
@@ -40,13 +44,9 @@ DepthCameraPlugin::~DepthCameraPlugin()
   this->newRGBPointCloudConnection.reset();
   this->newImageFrameConnection.reset();
 
-  std::map<DepthCameraPlugin*, event::ConnectionPtr>::iterator it;
-  it = connection_reflectance_map.find(this);
-  it->second.reset();
-  connection_reflectance_map.erase(it);
-  it = connection_normals_map.find(this);
-  it->second.reset();
-  connection_normals_map.erase(it);
+  std::lock_guard<std::mutex> guard{global_maps_mutex};
+  connection_reflectance_map.erase(this);
+  connection_normals_map.erase(this);
 
   this->parentSensor.reset();
   this->depthCamera.reset();
@@ -93,6 +93,7 @@ void DepthCameraPlugin::Load(sensors::SensorPtr _sensor,
             std::placeholders::_3, std::placeholders::_4,
             std::placeholders::_5));
 
+  std::lock_guard<std::mutex> guard{global_maps_mutex};
   connection_reflectance_map.
         insert(std::pair<DepthCameraPlugin*, event::ConnectionPtr>
                (this, newReflectanceFrameConnection));