Add option to use elogind

Signed-off-by: Stephan Lachnit <stephanlachnit@protonmail.com>

daemon/gamemode-dbus.c

@@ -36,8 +36,13 @@ POSSIBILITY OF SUCH DAMAGE.
 #include "common-logging.h"
 #include "common-pidfds.h"
 
+#ifdef USE_ELOGIND
+#include <elogind/sd-bus.h>
+#include <elogind/sd-daemon.h>
+#else
 #include <systemd/sd-bus.h>
 #include <systemd/sd-daemon.h>
+#endif
 
 #include <assert.h>
 #include <errno.h>

daemon/meson.build

@@ -17,6 +17,7 @@ gamemoded_includes += config_h_dir
 gamemoded = executable(
     'gamemoded',
     sources: daemon_sources,
+    c_args: elogind_args,
     dependencies: [
         link_daemon_common,
         dep_threads,

meson.build

@@ -79,9 +79,22 @@ path_libdir = join_paths(path_prefix, get_option('libdir'))
 path_libexecdir = join_paths(path_prefix, get_option('libexecdir'))
 path_sysconfdir = join_paths(path_prefix, get_option('sysconfdir'))
 
-# Find systemd via pkgconfig
+# Find systemd / elogind via pkgconfig
 with_systemd = get_option('with-systemd')
+with_elogind = get_option('with-elogind')
+elogind_args = []
+dep_systemd = []
+if with_systemd == true
+    if with_elogind == true
+        error('you can\'t use systemd and elogind at the same time')
+    endif
     dep_systemd = dependency('libsystemd')
+elif with_elogind == true
+    elogind_args += ['-DUSE_ELOGIND']
+    dep_systemd = dependency('libelogind')
+else
+    error('you need to use either sd-bus.h from systemd or elogind')
+endif
 
 # For the client, libdbus is used
 dep_dbus = dependency('dbus-1')

meson_options.txt

@@ -1,12 +1,12 @@
-option('with-systemd', type: 'boolean', description: 'Use systemd support (unit, etc)', value: 'true')
-
 # limits.d
 option('with-pam-group', type: 'string', description: 'Install the limits.d configuration file to allow renicing as an unpriviledged user being part of the specified group')
 
 # systemd specific
+option('with-systemd', type: 'boolean', description: 'Use systemd support (unit, etc)', value: true)
 option('with-systemd-user-unit-dir', type: 'string', description: 'Explicitly set the systemd user unit directory')
 
 # Not using systemd
+option('with-elogind', type: 'boolean', description: 'Use elogind\'s Dbus library', value: false)
 option('with-dbus-service-dir', type: 'string', description: 'Explicitly set the D-BUS session directory')
 
 # lib dir in gamemoderun