Commit 59ab9004 authored by David Herrmann's avatar David Herrmann Committed by Kristian Høgsberg

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.
parent afb9828d
......@@ -379,6 +379,28 @@ if test "x$enable_colord" != "xno"; then
fi
AM_CONDITIONAL(ENABLE_COLORD, test "x$enable_colord" = "xyes")
# dbus support
AC_ARG_ENABLE(dbus,
AS_HELP_STRING([--disable-dbus],
[do not build with dbus support]),,
enable_dbus=auto)
if test "x$enable_dbus" != "xno"; then
PKG_CHECK_MODULES(DBUS,
dbus-1 >= 1.6,
have_dbus=yes,
have_dbus=no)
if test "x$have_dbus" = "xno" -a "x$enable_dbus" = "xyes"; then
AC_MSG_ERROR([dbus support explicitly requested, but libdbus couldn't be found])
fi
if test "x$have_dbus" = "xyes"; then
enable_dbus=yes
AC_DEFINE([HAVE_DBUS], [1], [Build with dbus support])
else
enable_dbus=no
fi
fi
AM_CONDITIONAL(ENABLE_DBUS, test "x$enable_dbus" = "xyes")
AC_ARG_ENABLE(wcap-tools, [ --disable-wcap-tools],, enable_wcap_tools=yes)
AM_CONDITIONAL(BUILD_WCAP_TOOLS, test x$enable_wcap_tools = xyes)
if test x$enable_wcap_tools = xyes; then
......@@ -467,6 +489,7 @@ AC_MSG_RESULT([
EGL ${enable_egl}
libxkbcommon ${enable_xkbcommon}
XWayland ${enable_xwayland}
dbus ${enable_dbus}
Build wcap utility ${enable_wcap_tools}
Build Tablet Shell ${enable_tablet_shell}
......
......@@ -49,6 +49,14 @@ weston_SOURCES = \
weston-launch.h \
weston-egl-ext.h
if ENABLE_DBUS
weston_SOURCES += \
dbus.h \
dbus.c
weston_CFLAGS += $(DBUS_CFLAGS)
weston_LDADD += $(DBUS_LIBS)
endif
git-version.h : .FORCE
$(AM_V_GEN)(echo "#define BUILD_ID \"$(shell git --git-dir=$(top_srcdir)/.git describe --always --dirty) $(shell git --git-dir=$(top_srcdir)/.git log -1 --format='%s (%ci)')\"" > $@-new; \
cmp -s $@ $@-new || cp $@-new $@; \
......
/*
* 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.
*/
/*
* DBus Helpers
* This file contains the dbus mainloop integration and several helpers to
* make lowlevel libdbus access easier.
*/
#include "config.h"
#include <dbus/dbus.h>
#include <errno.h>
#include <fcntl.h>
#include <stdbool.h>
#include <stdlib.h>
#include <string.h>
#include <sys/epoll.h>
#include <sys/eventfd.h>
#include <sys/timerfd.h>
#include <unistd.h>
#include <wayland-server.h>
#include "compositor.h"
#include "dbus.h"
/*
* DBus Mainloop Integration
* weston_dbus_bind() and weston_dbus_unbind() allow to bind an existing
* DBusConnection to an existing wl_event_loop object. All dbus dispatching
* is then nicely integrated into the wayland event loop.
* Note that this only provides basic watch and timeout dispatching. No
* remote thread wakeup, signal handling or other dbus insanity is supported.
* This is fine as long as you don't use any of the deprecated libdbus
* interfaces (like waking up remote threads..). There is really no rational
* reason to support these.
*/
static int weston_dbus_dispatch_watch(int fd, uint32_t mask, void *data)
{
DBusWatch *watch = data;
uint32_t flags = 0;
if (dbus_watch_get_enabled(watch)) {
if (mask & WL_EVENT_READABLE)
flags |= DBUS_WATCH_READABLE;
if (mask & WL_EVENT_WRITABLE)
flags |= DBUS_WATCH_WRITABLE;
if (mask & WL_EVENT_HANGUP)
flags |= DBUS_WATCH_HANGUP;
if (mask & WL_EVENT_ERROR)
flags |= DBUS_WATCH_ERROR;
dbus_watch_handle(watch, flags);
}
return 0;
}
static dbus_bool_t weston_dbus_add_watch(DBusWatch *watch, void *data)
{
struct wl_event_loop *loop = data;
struct wl_event_source *s;
int fd;
uint32_t mask = 0, flags;
if (dbus_watch_get_enabled(watch)) {
flags = dbus_watch_get_flags(watch);
if (flags & DBUS_WATCH_READABLE)
mask |= WL_EVENT_READABLE;
if (flags & DBUS_WATCH_WRITABLE)
mask |= WL_EVENT_WRITABLE;
}
fd = dbus_watch_get_unix_fd(watch);
s = wl_event_loop_add_fd(loop, fd, mask, weston_dbus_dispatch_watch,
watch);
if (!s)
return FALSE;
dbus_watch_set_data(watch, s, NULL);
return TRUE;
}
static void weston_dbus_remove_watch(DBusWatch *watch, void *data)
{
struct wl_event_source *s;
s = dbus_watch_get_data(watch);
if (!s)
return;
wl_event_source_remove(s);
}
static void weston_dbus_toggle_watch(DBusWatch *watch, void *data)
{
struct wl_event_source *s;
uint32_t mask = 0, flags;
s = dbus_watch_get_data(watch);
if (!s)
return;
if (dbus_watch_get_enabled(watch)) {
flags = dbus_watch_get_flags(watch);
if (flags & DBUS_WATCH_READABLE)
mask |= WL_EVENT_READABLE;
if (flags & DBUS_WATCH_WRITABLE)
mask |= WL_EVENT_WRITABLE;
}
wl_event_source_fd_update(s, mask);
}
static int weston_dbus_dispatch_timeout(void *data)
{
DBusTimeout *timeout = data;
if (dbus_timeout_get_enabled(timeout))
dbus_timeout_handle(timeout);
return 0;
}
static int weston_dbus_adjust_timeout(DBusTimeout *timeout,
struct wl_event_source *s)
{
int64_t t = 0;
if (dbus_timeout_get_enabled(timeout))
t = dbus_timeout_get_interval(timeout);
return wl_event_source_timer_update(s, t);
}
static dbus_bool_t weston_dbus_add_timeout(DBusTimeout *timeout, void *data)
{
struct wl_event_loop *loop = data;
struct wl_event_source *s;
int r;
s = wl_event_loop_add_timer(loop, weston_dbus_dispatch_timeout,
timeout);
if (!s)
return FALSE;
r = weston_dbus_adjust_timeout(timeout, s);
if (r < 0) {
wl_event_source_remove(s);
return FALSE;
}
dbus_timeout_set_data(timeout, s, NULL);
return TRUE;
}
static void weston_dbus_remove_timeout(DBusTimeout *timeout, void *data)
{
struct wl_event_source *s;
s = dbus_timeout_get_data(timeout);
if (!s)
return;
wl_event_source_remove(s);
}
static void weston_dbus_toggle_timeout(DBusTimeout *timeout, void *data)
{
struct wl_event_source *s;
s = dbus_timeout_get_data(timeout);
if (!s)
return;
weston_dbus_adjust_timeout(timeout, s);
}
static int weston_dbus_dispatch(int fd, uint32_t mask, void *data)
{
DBusConnection *c = data;
int r;
do {
r = dbus_connection_dispatch(c);
if (r == DBUS_DISPATCH_COMPLETE)
r = 0;
else if (r == DBUS_DISPATCH_DATA_REMAINS)
r = -EAGAIN;
else if (r == DBUS_DISPATCH_NEED_MEMORY)
r = -ENOMEM;
else
r = -EIO;
} while (r == -EAGAIN);
if (r)
weston_log("cannot dispatch dbus events: %d\n", r);
return 0;
}
static int weston_dbus_bind(struct wl_event_loop *loop, DBusConnection *c,
struct wl_event_source **ctx_out)
{
bool b;
int r, fd;
/* Idle events cannot reschedule themselves, therefore we use a dummy
* event-fd and mark it for post-dispatch. Hence, the dbus
* dispatcher is called after every dispatch-round.
* This is required as dbus doesn't allow dispatching events from
* within its own event sources. */
fd = eventfd(0, EFD_CLOEXEC);
if (fd < 0)
return -errno;
*ctx_out = wl_event_loop_add_fd(loop, fd, 0, weston_dbus_dispatch, c);
close(fd);
if (!*ctx_out)
return -ENOMEM;
wl_event_source_check(*ctx_out);
b = dbus_connection_set_watch_functions(c,
weston_dbus_add_watch,
weston_dbus_remove_watch,
weston_dbus_toggle_watch,
loop,
NULL);
if (!b) {
r = -ENOMEM;
goto error;
}
b = dbus_connection_set_timeout_functions(c,
weston_dbus_add_timeout,
weston_dbus_remove_timeout,
weston_dbus_toggle_timeout,
loop,
NULL);
if (!b) {
r = -ENOMEM;
goto error;
}
dbus_connection_ref(c);
return 0;
error:
dbus_connection_set_timeout_functions(c, NULL, NULL, NULL,
NULL, NULL);
dbus_connection_set_watch_functions(c, NULL, NULL, NULL,
NULL, NULL);
wl_event_source_remove(*ctx_out);
*ctx_out = NULL;
return r;
}
static void weston_dbus_unbind(DBusConnection *c, struct wl_event_source *ctx)
{
dbus_connection_set_timeout_functions(c, NULL, NULL, NULL,
NULL, NULL);
dbus_connection_set_watch_functions(c, NULL, NULL, NULL,
NULL, NULL);
dbus_connection_unref(c);
wl_event_source_remove(ctx);
}
/*
* Convenience Helpers
* Several convenience helpers are provided to make using dbus in weston
* easier. We don't use any of the gdbus or qdbus helpers as they pull in
* huge dependencies and actually are quite awful to use. Instead, we only
* use the basic low-level libdbus library.
*/
int weston_dbus_open(struct wl_event_loop *loop, DBusBusType bus,
DBusConnection **out, struct wl_event_source **ctx_out)
{
DBusConnection *c;
int r;
/* Ihhh, global state.. stupid dbus. */
dbus_connection_set_change_sigpipe(FALSE);
/* This is actually synchronous. It blocks for some authentication and
* setup. We just trust the dbus-server here and accept this blocking
* call. There is no real reason to complicate things further and make
* this asynchronous/non-blocking. A context should be created during
* thead/process/app setup, so blocking calls should be fine. */
c = dbus_bus_get_private(bus, NULL);
if (!c)
return -EIO;
dbus_connection_set_exit_on_disconnect(c, FALSE);
r = weston_dbus_bind(loop, c, ctx_out);
if (r < 0)
goto error;
*out = c;
return r;
error:
dbus_connection_close(c);
dbus_connection_unref(c);
return r;
}
void weston_dbus_close(DBusConnection *c, struct wl_event_source *ctx)
{
weston_dbus_unbind(c, ctx);
dbus_connection_close(c);
dbus_connection_unref(c);
}
/*
* 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_
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