[gnome-settings-daemon/wip/timerfd] build: Define HAVE_TIMERFD if we have timerfd_create

[Iain Lane <iainl src gnome org>]

commit 4f4c6daaf3f85a39decc42539a90926512a86b52
Author: Iain Lane <iainl gnome org>
Date:   Tue Sep 18 08:23:30 2018 +0100

    build: Define HAVE_TIMERFD if we have timerfd_create
    
    If we have timerfd support we will use it to wake up at the appropriate
    time. There is a fallback non-timerfd path in which we wake up every
    second.
    
    The problem is that we had forgotten to ever check for timerfd support.
    Add a check to the build system which enables this if timerfd_create()
    exists.
    
    Closes: #77

 meson.build | 3 +++
 1 file changed, 3 insertions(+)
---
diff --git a/meson.build b/meson.build
index 2fd30cbd..e882d42c 100644
--- a/meson.build
+++ b/meson.build
@@ -125,6 +125,9 @@ if enable_gudev
 endif
 config_h.set('HAVE_GUDEV', enable_gudev)
 
+has_timerfd_create = cc.has_function('timerfd_create')
+config_h.set10('HAVE_TIMERFD', has_timerfd_create)
+
 # Check for libwayland-client
 enable_wayland = get_option('wayland')
 if enable_wayland