factored common X windows screen stuff into a common base class.

synergy/CXWindowsScreen.h

@@ -0,0 +1,73 @@
+#ifndef CXWINDOWSSCREEN_H
+#define CXWINDOWSSCREEN_H
+
+#include "CMutex.h"
+#include "BasicTypes.h"
+#include <X11/Xlib.h>
+
+class CThread;
+
+class CXWindowsScreen {
+  public:
+	CXWindowsScreen();
+	virtual ~CXWindowsScreen();
+
+  protected:
+	class CDisplayLock {
+	  public:
+		CDisplayLock(const CXWindowsScreen*);
+		~CDisplayLock();
+
+		operator Display*() const;
+
+	  private:
+		const CMutex*	m_mutex;
+		Display*		m_display;
+	};
+	friend class CDisplayLock;
+
+	// open the X display.  calls onOpenDisplay() after opening the display,
+	// getting the screen, its size, and root window.  then it starts the
+	// event thread.
+	void				openDisplay();
+
+	// destroy the window and close the display.  calls onCloseDisplay()
+	// after the event thread has been shut down but before the display
+	// is closed.
+	void				closeDisplay();
+
+	// get the opened screen, its size, its root window.  to get the
+	// display create a CDisplayLock object passing this.  while the
+	// object exists no other threads may access the display.  do not
+	// save the Display* beyond the lifetime of the CDisplayLock.
+	int					getScreen() const;
+	void				getScreenSize(SInt32* w, SInt32* h) const;
+	Window				getRoot() const;
+
+	// create a cursor that is transparent everywhere
+	Cursor				createBlankCursor() const;
+
+	// wait for and get the next X event.  cancellable.
+	void				getEvent(XEvent*) const;
+
+	// called by openDisplay() to allow subclasses to prepare the display
+	virtual void		onOpenDisplay() = 0;
+
+	// called by closeDisplay() to 
+	virtual void		onCloseDisplay() = 0;
+
+	// override to process X events
+	virtual void		eventThread(void*) = 0;
+
+  private:
+	CThread*			m_eventThread;
+	Display*			m_display;
+	int					m_screen;
+	Window				m_root;
+	SInt32				m_w, m_h;
+
+	// X is not thread safe
+	CMutex				m_mutex;
+};
+
+#endif