From 9c3907050c747253238ae8c0def1901f10aba457 Mon Sep 17 00:00:00 2001
From: Ian Hunt-Isaak <ianhuntisaak@gmail.com>
Date: Wed, 23 Feb 2022 23:13:34 -0500
Subject: [PATCH] add locks to async leader/follower props

---
 DeviceAdapters/DemoCamera/DemoCamera.cpp | 3 +++
 DeviceAdapters/DemoCamera/DemoCamera.h   | 2 ++
 2 files changed, 5 insertions(+)

diff --git a/DeviceAdapters/DemoCamera/DemoCamera.cpp b/DeviceAdapters/DemoCamera/DemoCamera.cpp
index 284a66189..7f53a4fa6 100644
--- a/DeviceAdapters/DemoCamera/DemoCamera.cpp
+++ b/DeviceAdapters/DemoCamera/DemoCamera.cpp
@@ -1307,12 +1307,14 @@ void CDemoCamera::SlowPropUpdate()
       // in a thread
       long delay; GetProperty("AsyncPropertyDelayMS", delay);
       CDeviceUtils::SleepMs(delay);
+      MMThreadGuard g(asyncFollowerLock_);
       asyncFollower = asyncLeader;
       OnPropertyChanged("AsyncPropertyFollower", asyncFollower.c_str());
    }
 
 int CDemoCamera::OnAsyncFollower(MM::PropertyBase* pProp, MM::ActionType eAct)
 {
+   MMThreadGuard g(asyncFollowerLock_);
    if (eAct == MM::BeforeGet){
       pProp->Set(asyncFollower.c_str());
    }
@@ -1322,6 +1324,7 @@ int CDemoCamera::OnAsyncFollower(MM::PropertyBase* pProp, MM::ActionType eAct)
 
 int CDemoCamera::OnAsyncLeader(MM::PropertyBase* pProp, MM::ActionType eAct)
 {
+   MMThreadGuard g(asyncLeaderLock_);
    if (eAct == MM::BeforeGet){
       pProp->Set(asyncLeader.c_str());
    }
diff --git a/DeviceAdapters/DemoCamera/DemoCamera.h b/DeviceAdapters/DemoCamera/DemoCamera.h
index af6b7e317..8a6825a75 100644
--- a/DeviceAdapters/DemoCamera/DemoCamera.h
+++ b/DeviceAdapters/DemoCamera/DemoCamera.h
@@ -272,6 +272,8 @@ class CDemoCamera : public CCameraBase<CDemoCamera>
    std::string asyncLeader;
    std::string asyncFollower;
    MMThreadLock imgPixelsLock_;
+   MMThreadLock asyncLeaderLock_;
+   MMThreadLock asyncFollowerLock_;
    friend class MySequenceThread;
    int nComponents_;
    MySequenceThread * thd_;