[gnome-boxes] build: Make oVirt support optional

[Felipe Borges <felipeborges src gnome org>]

commit db5d242f763401e6787368f7a3b0d52fe733ec01
Author: Iñigo Martínez <inigomartinez gmail com>
Date:   Mon Feb 12 15:43:21 2018 +0100

    build: Make oVirt support optional
    
    Although there is an option to make oVirt support optinal, the
    GObject-based library to access oVirt REST API must be available
    to build gnome-boxes.
    
    This patch makes the library dependency optional if the oVirt
    support is disabled by using vala preprocessor[0].
    
    [0] https://wiki.gnome.org/Projects/Vala/Manual/Preprocessor

 meson.build     |  5 -----
 src/app.vala    |  5 +++--
 src/config.vapi |  1 -
 src/meson.build | 33 +++++++++++++--------------------
 4 files changed, 16 insertions(+), 28 deletions(-)
---
diff --git a/meson.build b/meson.build
index a074028e..d6119298 100644
--- a/meson.build
+++ b/meson.build
@@ -11,7 +11,6 @@ i18n = import ('i18n')
 cc = meson.get_compiler ('c')
 valac = meson.get_compiler ('vala')
 
-govirt_dep = dependency ('govirt-1.0', version: '>= 0.3.4')
 libarchive_dep = dependency ('libarchive', version: '>= 3.0.0')
 
 src_dir = join_paths (meson.source_root (), 'src')
@@ -38,10 +37,6 @@ conf.set_quoted ('CACHEDIR', '/var/cache')
 conf.set_quoted ('LOCALEDIR', locale_dir)
 conf.set('PACKAGE_BUGREPORT', '"https://bugzilla.gnome.org/enter_bug.cgi?product=gnome-boxes";')
 
-if govirt_dep.found()
-  conf.set10 ('HAVE_OVIRT', get_option ('ovirt'))
-endif
-
 configure_file (output: 'config.h', configuration: conf)
 config_h_dir = include_directories ('.')
 
diff --git a/src/app.vala b/src/app.vala
index e56c582c..89aba7a8 100644
--- a/src/app.vala
+++ b/src/app.vala
@@ -127,8 +127,9 @@ public override void startup () {
         collection = new Collection ();
 
         brokers.insert ("libvirt", LibvirtBroker.get_default ());
-        if (Config.HAVE_OVIRT)
-            brokers.insert ("ovirt", OvirtBroker.get_default ());
+#if HAVE_OVIRT
+        brokers.insert ("ovirt", OvirtBroker.get_default ());
+#endif
 
         check_cpu_vt_capability.begin ();
         check_module_kvm_loaded.begin ();
diff --git a/src/config.vapi b/src/config.vapi
index 15e1eff6..92409b51 100644
--- a/src/config.vapi
+++ b/src/config.vapi
@@ -11,5 +11,4 @@ namespace Config {
         public const string CACHEDIR;
         public const string PACKAGE_BUGREPORT;
         public const string PACKAGE_URL;
-        public const bool HAVE_OVIRT;
 }
diff --git a/src/meson.build b/src/meson.build
index 8adce5cb..1b4ae44d 100644
--- a/src/meson.build
+++ b/src/meson.build
@@ -114,20 +114,6 @@ vala_sources = [
   'snapshots-property.vala',
 ]
 
-if govirt_dep.found ()
-  if get_option ('ovirt')
-    vala_sources += [
-      'ovirt-broker.vala',
-      'ovirt-machine.vala',
-    ]
-  endif
-endif
-
-boxes_sources = [
-  vala_sources,
-  resources
-]
-
 dependencies = [
   config_dep,
   libarchive_dep,
@@ -148,17 +134,24 @@ dependencies = [
   valac.find_library ('gio-2.0-workaround', dirs: vapi_dir),
   valac.find_library ('linux'),
   valac.find_library ('posix'),
-  valac.find_library ('rest-0.7'),
   valac.find_library ('spice-client-gtk-3.0'),
 ]
 
-if govirt_dep.found()
-  if get_option ('ovirt')
-    dependencies += govirt_dep
-  endif
+if get_option('ovirt')
+  vala_sources += [
+    'ovirt-broker.vala',
+    'ovirt-machine.vala'
+  ]
+
+  vala_args += '--define=HAVE_OVIRT'
+
+  dependencies += [
+    dependency ('govirt-1.0', version: '>= 0.3.4'),
+    valac.find_library ('rest-0.7')
+  ]
 endif
 
-executable ('gnome-boxes', boxes_sources,
+executable ('gnome-boxes', vala_sources + resources,
             include_directories: config_h_dir,
             vala_args: vala_args,
             c_args : c_args,