Add optional dbus helpers

This adds optional libdbus integration for weston. If libdbus is available
and not disabled via --disable-dbus during weston build, we now provide
basic DBusConnection main-loop integration for weston.

The dbus.c file provides a new helper to integrate any DBusConnection
object into a wl_event_loop object. This avoids any glib/qt/..
dependencies but instead only uses the low-level libdbus library.

Note that we do not provide dummy fallbacks for dbus helpers in case
dbus-support is disabled. The reason for that is that you need dbus/dbus.h
for nearly any operation you want to do via dbus. Therefore, only the most
basic helpers which can be used independently provide a "static inline"
dummy fallback to avoid #ifdef all over the code.

1 files changed, 67 insertions, 0 deletions

diff --git a/src/dbus.h b/src/dbus.h
new file mode 100644
index 00000000..90ab8f61
--- /dev/null
+++ b/src/dbus.h
@@ -0,0 +1,67 @@
+/*
+ * Copyright © 2013 David Herrmann <dh.herrmann@gmail.com>
+ *
+ * Permission to use, copy, modify, distribute, and sell this software and
+ * its documentation for any purpose is hereby granted without fee, provided
+ * that the above copyright notice appear in all copies and that both that
+ * copyright notice and this permission notice appear in supporting
+ * documentation, and that the name of the copyright holders not be used in
+ * advertising or publicity pertaining to distribution of the software
+ * without specific, written prior permission.  The copyright holders make
+ * no representations about the suitability of this software for any
+ * purpose.  It is provided "as is" without express or implied warranty.
+ *
+ * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS
+ * SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ * FITNESS, IN NO EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY
+ * SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER
+ * RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF
+ * CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
+ * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#ifndef _WESTON_DBUS_H_
+#define _WESTON_DBUS_H_
+
+#include "config.h"
+
+#include <errno.h>
+#include <wayland-server.h>
+
+#include "compositor.h"
+
+#ifdef HAVE_DBUS
+
+#include <dbus/dbus.h>
+
+/*
+ * weston_dbus_open() - Open new dbus connection
+ *
+ * Opens a new dbus connection to the bus given as @bus. It automatically
+ * integrates the new connection into the main-loop @loop. The connection
+ * itself is returned in @out.
+ * This also returns a context source used for dbus dispatching. It is
+ * returned on success in @ctx_out and must be passed to weston_dbus_close()
+ * unchanged. You must not access it from outside of a dbus helper!
+ *
+ * Returns 0 on success, negative error code on failure.
+ */
+int weston_dbus_open(struct wl_event_loop *loop, DBusBusType bus,
+		     DBusConnection **out, struct wl_event_source **ctx_out);
+
+/*
+ * weston_dbus_close() - Close dbus connection
+ *
+ * Closes a dbus connection that was previously opened via weston_dbus_open().
+ * It unbinds the connection from the main-loop it was previously bound to,
+ * closes the dbus connection and frees all resources. If you want to access
+ * @c after this call returns, you must hold a dbus-reference to it. But
+ * notice that the connection is closed after this returns so it cannot be
+ * used to spawn new dbus requests.
+ * You must pass the context source returns by weston_dbus_open() as @ctx.
+ */
+void weston_dbus_close(DBusConnection *c, struct wl_event_source *ctx);
+
+#endif /* HAVE_DBUS */
+
+#endif // _WESTON_DBUS_H_