Allow disconnections to be signaled by drivers

This allows for disconnections to be detected quickly
where possible.

It also makes sure other driver errors aren't thrown
in the event of a disconnection.

include/icsneo/communication/communication.h

@@ -37,6 +37,7 @@ public:
 	bool open();
 	bool close();
 	bool isOpen();
+	bool isDisconnected();
 	virtual void spawnThreads();
 	virtual void joinThreads();
 	bool rawWrite(const std::vector<uint8_t>& bytes) { return driver->write(bytes); }

include/icsneo/communication/driver.h

@@ -20,6 +20,7 @@ public:
 	virtual ~Driver() {}
 	virtual bool open() = 0;
 	virtual bool isOpen() = 0;
+	virtual bool isDisconnected() { return disconnected; };
 	virtual bool close() = 0;
 	virtual bool read(std::vector<uint8_t>& bytes, size_t limit = 0);
 	virtual bool readWait(std::vector<uint8_t>& bytes, std::chrono::milliseconds timeout = std::chrono::milliseconds(100), size_t limit = 0);
@@ -47,6 +48,7 @@ protected:
 	moodycamel::BlockingConcurrentQueue<WriteOperation> writeQueue;
 	std::thread readThread, writeThread;
 	std::atomic<bool> closing{false};
+	std::atomic<bool> disconnected{false};
 };
 
 }

include/icsneo/device/device.h

@@ -49,6 +49,7 @@ public:
 	virtual bool close();
 	virtual bool isOnline() const { return online; }
 	virtual bool isOpen() const { return com->isOpen(); }
+	virtual bool isDisconnected() const { return com->isDisconnected(); }
 	virtual bool goOnline();
 	virtual bool goOffline();
 

include/icsneo/platform/posix/ftdi.h

@@ -19,7 +19,7 @@ public:
 	static std::vector<neodevice_t> FindByProduct(int product);
 
 	FTDI(const device_eventhandler_t& err, neodevice_t& forDevice);
-	~FTDI() { close(); }
+	~FTDI() { if(isOpen()) close(); }
 	bool open();
 	bool close();
 	bool isOpen() { return ftdi.isOpen(); }

include/icsneo/platform/posix/stm32.h

@@ -24,6 +24,7 @@ public:
 	 * Other POSIX systems (BSDs, QNX, etc) will need bespoke code written in the future
 	 */
 	STM32(const device_eventhandler_t& err, neodevice_t& forDevice) : Driver(err), device(forDevice) {}
+	~STM32() { if(isOpen()) close(); }
 	static std::vector<neodevice_t> FindByProduct(int product);
 
 	bool open();
@@ -38,6 +39,7 @@ private:
 
 	void readTask();
 	void writeTask();
+	bool fdIsValid();
 };
 
 }