#include "pbd/libpbd_visibility.h"
+#ifdef PLATFORM_WINDOWS
+#include <windows.h>
+#endif // PLATFORM_WINDOWS
+
+
/** A simple abstraction of a mechanism of signalling one thread from another.
* The signaller calls ::wakeup() to tell the signalled thread to check for
* work to be done.
*/
class LIBPBD_API CrossThreadChannel {
- public:
+public:
/** if @a non_blocking is true, the channel will not cause blocking
* when used in an event loop based on poll/select or the glib main
* loop.
* because there is no way to know which byte value will be used
* for ::wakeup()
*/
- int deliver (char msg);
+ int deliver (char msg);
/** if using ::deliver() to wakeup the listening thread, then
* the listener should call ::receive() to fetch the message
* type from the channel.
+ *
+ * wait = true only make sense for non_blocking channels,
+ * it polls for data to become available.
*/
- int receive (char& msg);
+ int receive (char& msg, bool wait = false);
/** empty the channel of all requests.
* Typically this is done as soon as input
* in the channel will not be important.
*/
void drain ();
- static void drain (int fd);
- /** File descriptor that can be used with poll/select to
- * detect when wakeup() has been called on this channel.
- * It be marked as readable/input-ready when this condition
- * is true. It has already been marked non-blocking.
- */
- int selectable() const { return fds[0]; }
-
- /* glibmm 2.22 and earlier has a terrifying bug that will
- cause crashes whenever a Source is removed from
- a MainContext (including the destruction of the MainContext),
- because the Source is destroyed "out from under the nose of"
- the RefPtr. I (Paul) have fixed this (https://bugzilla.gnome.org/show_bug.cgi?id=561885)
- but in the meantime, we need a hack to get around the issue.
- */
- Glib::RefPtr<Glib::IOSource> ios();
- void drop_ios ();
-
- /** returns true if the CrossThreadChannel was
- * correctly constructed.
- */
- bool ok() const { return fds[0] >= 0 && fds[1] >= 0; }
+ void set_receive_handler (sigc::slot<bool,Glib::IOCondition> s);
+ void attach (Glib::RefPtr<Glib::MainContext>);
+
+private:
+ friend gboolean cross_thread_channel_call_receive_slot (GIOChannel*, GIOCondition condition, void *data);
- private:
- Glib::RefPtr<Glib::IOSource>* _ios; // lazily constructed
+ GIOChannel* receive_channel;
+ GSource* receive_source;
+ sigc::slot<bool,Glib::IOCondition> receive_slot;
+
+ bool poll_for_request();
+
+#ifndef PLATFORM_WINDOWS
int fds[2]; // current implementation uses a pipe/fifo
+#else
+
+ SOCKET send_socket;
+ SOCKET receive_socket;
+ struct sockaddr_in recv_address;
+#endif
+
};
#endif /* __pbd__crossthread_h__ */