qcam: Add Qt-based GUI application

qcam is a sample camera GUI application based on Qt. It demonstrates
integration of the Qt event loop with libcamera.

The application lets the user select a camera through the GUI, and then
captures a single stream from the camera and displays it in a window.
Only streams in YUYV formats are supported for now.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Tested-by: Kieran Bingham <kieran.bingham@ideasonboard.com>

1 files changed, 62 insertions, 0 deletions

diff --git a/src/qcam/qt_event_dispatcher.h b/src/qcam/qt_event_dispatcher.h
new file mode 100644
index 00000000..b0f123e5
--- /dev/null
+++ b/src/qcam/qt_event_dispatcher.h
@@ -0,0 +1,62 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (C) 2019, Google Inc.
+ *
+ * qt_event_dispatcher.h - qcam - Qt-based event dispatcher
+ */
+#ifndef __QCAM_QT_EVENT_DISPATCHER_H__
+#define __QCAM_QT_EVENT_DISPATCHER_H__
+
+#include <map>
+
+#include <libcamera/event_dispatcher.h>
+
+using namespace libcamera;
+
+class QSocketNotifier;
+
+class QtEventDispatcher final : public EventDispatcher, public QObject
+{
+public:
+	QtEventDispatcher();
+	~QtEventDispatcher();
+
+	void registerEventNotifier(EventNotifier *notifier);
+	void unregisterEventNotifier(EventNotifier *notifier);
+
+	void registerTimer(Timer *timer);
+	void unregisterTimer(Timer *timer);
+
+	void processEvents();
+
+	void interrupt();
+
+protected:
+	void timerEvent(QTimerEvent *event);
+
+private:
+	void readNotifierActivated(int socket);
+	void writeNotifierActivated(int socket);
+	void exceptionNotifierActivated(int socket);
+
+	struct NotifierPair {
+		NotifierPair()
+			: notifier(nullptr), qnotifier(nullptr)
+		{
+		}
+		EventNotifier *notifier;
+		QSocketNotifier *qnotifier;
+	};
+
+	struct NotifierSet {
+		NotifierPair read;
+		NotifierPair write;
+		NotifierPair exception;
+	};
+
+	std::map<int, NotifierSet> notifiers_;
+	std::map<int, Timer *> timers_;
+	std::map<Timer *, int> timerIds_;
+};
+
+#endif /* __QCAM_QT_EVENT_DISPATCHER_H__ */