Fix #605 by closing current device when another is selected

As the device manager class holds a pointer to all devices
they will never be destroyed until PV exits. Devices are
opened with the first call to create() but only closed in
the destructor. Together, this results in devices never
being closed.

This patch fixes this by renaming create() to open()
and introducing a matching close() method that the
session class calls when a different device is to be
selected.

pv/devices/device.hpp

@@ -64,7 +64,9 @@ class Device
 	virtual std::string display_name(
 		const DeviceManager &device_manager) const = 0;
 
-	virtual void create() = 0;
+	virtual void open() = 0;
+
+	virtual void close() = 0;
 
 	virtual void start();
 

pv/devices/hardwaredevice.cpp

@@ -49,11 +49,7 @@ HardwareDevice::HardwareDevice(const std::shared_ptr<sigrok::Context> &context,
 }
 
 HardwareDevice::~HardwareDevice() {
-	if (device_open_)
-		device_->close();
-
-	if (session_)
-		session_->remove_devices();
+	close();
 }
 
 string HardwareDevice::full_name() const {
@@ -99,8 +95,10 @@ string HardwareDevice::display_name(
 	return join(parts, " ");
 }
 
-void HardwareDevice::create() {
-	// Open the device
+void HardwareDevice::open() {
+	if (device_open_)
+		close();
+
 	try {
 		device_->open();
 	} catch(const sigrok::Error &e) {
@@ -114,5 +112,15 @@ void HardwareDevice::create() {
 	session_->add_device(device_);
 }
 
+void HardwareDevice::close() {
+	if (device_open_)
+		device_->close();
+
+	if (session_)
+		session_->remove_devices();
+
+	device_open_ = false;
+}
+
 } // namespace devices
 } // namespace pv

pv/devices/hardwaredevice.hpp

@@ -53,7 +53,9 @@ class HardwareDevice final : public Device
 	 */
 	std::string display_name(const DeviceManager &device_manager) const;
 
-	void create();
+	void open();
+
+	void close();
 
 private:
 	const std::shared_ptr<sigrok::Context> context_;

pv/devices/inputfile.cpp

@@ -42,10 +42,18 @@ InputFile::InputFile(const std::shared_ptr<sigrok::Context> &context,
 		throw QString("Failed to create input");
 }
 
-void InputFile::create() {
+void InputFile::open() {
+	if (session_)
+		close();
+
 	session_ = context_->create_session();
 }
 
+void InputFile::close() {
+	if (session_)
+		session_->remove_devices();
+}
+
 void InputFile::start() {
 }
 

pv/devices/inputfile.hpp

@@ -41,7 +41,9 @@ class InputFile final : public File
 		std::shared_ptr<sigrok::InputFormat> format,
 		const std::map<std::string, Glib::VariantBase> &options);
 
-	void create();
+	void open();
+
+	void close();
 
 	void start();
 

pv/devices/sessionfile.cpp

@@ -33,10 +33,18 @@ SessionFile::SessionFile(const std::shared_ptr<sigrok::Context> context,
 	context_(context) {
 }
 
-void SessionFile::create() {
+void SessionFile::open() {
+	if (session_)
+		close();
+
 	session_ = context_->load_session(file_name_);
 	device_ = session_->devices()[0];
 }
 
+void SessionFile::close() {
+	if (session_)
+		session_->remove_devices();
+}
+
 } // namespace devices
 } // namespace pv

pv/devices/sessionfile.hpp

@@ -38,7 +38,9 @@ class SessionFile final : public File
 	SessionFile(const std::shared_ptr<sigrok::Context> context,
 		const std::string &file_name);
 
-	void create();
+	void open();
+
+	void close();
 
 private:
 	const std::shared_ptr<sigrok::Context> context_;

pv/session.cpp

@@ -127,8 +127,11 @@ void Session::set_device(shared_ptr<devices::Device> device)
 	// Ensure we are not capturing before setting the device
 	stop_capture();
 
+	if (device_)
+		device_->close();
+
 	device_ = std::move(device);
-	device_->create();
+	device_->open();
 	device_->session()->add_datafeed_callback([=]
 		(shared_ptr<sigrok::Device> device, shared_ptr<Packet> packet) {
 			data_feed_in(device, packet);