From 026d2bdd10305dd33baca58431a296a63d274f0d Mon Sep 17 00:00:00 2001
From: Ralf Ramsauer <ralf@ramses-pyramidenbau.de>
Date: Mon, 31 Aug 2015 19:01:37 +0200
Subject: [PATCH] Added mutex to door.cpp to prevent lock collissions

Signed-off-by: Ralf Ramsauer <ralf@ramses-pyramidenbau.de>
---
 doorlockd/door.cpp | 2 ++
 doorlockd/door.h   | 4 ++++
 2 files changed, 6 insertions(+)

diff --git a/doorlockd/door.cpp b/doorlockd/door.cpp
index 96ac903..adf1099 100644
--- a/doorlockd/door.cpp
+++ b/doorlockd/door.cpp
@@ -39,6 +39,8 @@ Door::State Door::state() const
 
 void Door::lock()
 {
+    std::lock_guard<std::mutex> l(_mutex);
+
     _l(LogLevel::notice, "Executing Pre Lock Script");
     system(PRE_LOCK_SCRIPT);
 
diff --git a/doorlockd/door.h b/doorlockd/door.h
index 614720a..134a5b0 100644
--- a/doorlockd/door.h
+++ b/doorlockd/door.h
@@ -3,6 +3,7 @@
 
 #include <string>
 #include <thread>
+#include <mutex>
 
 #include "logger.h"
 
@@ -52,6 +53,9 @@ private:
     // Read by the Heartbeat thread if it should klacker the schnapper or not
     bool _schnapper = { false };
 
+    // Mutex to avoid concurrent locks
+    std::mutex _mutex = { };
+
     // WiringPi GPIO Pins
     static constexpr int _HEARTBEATPIN = 10;
     static constexpr int _SCHNAPPERPIN = 7;