[nautilus] meson: actually use optional dependencies

[Ernestas Kulik <ernestask src gnome org>]

commit 63a7e1ebad21787db9b4d2a6bf2f29067a84b75f
Author: Ernestas Kulik <ernestask gnome org>
Date:   Sat Mar 11 00:30:29 2017 +0200

    meson: actually use optional dependencies
    
    EXIF and Exempi are currently only being detected due to an oversight.
    This commit makes Meson define the preprocessor macros needed to use the
    libraries.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=779879

 config.h.meson  |    2 ++
 meson.build     |   34 ++++++++++++++++------------------
 src/meson.build |    8 ++++++++
 3 files changed, 26 insertions(+), 18 deletions(-)
---
diff --git a/config.h.meson b/config.h.meson
index 6391b75..c494c9c 100644
--- a/config.h.meson
+++ b/config.h.meson
@@ -1,6 +1,8 @@
 #mesondefine VERSION
 #mesondefine PACKAGE_VERSION
 #mesondefine GETTEXT_PACKAGE
+#mesondefine HAVE_EXEMPI
+#mesondefine HAVE_EXIF
 #mesondefine HAVE_SELINUX
 #mesondefine ENABLE_DESKTOP
 #mesondefine ENABLE_PACKAGEKIT
diff --git a/meson.build b/meson.build
index 63f13c4..6aa7312 100644
--- a/meson.build
+++ b/meson.build
@@ -55,20 +55,6 @@ gsettings_desktop_schemas = dependency ('gsettings-desktop-schemas',
 
 libm = cc.find_library ('libm')
 
-exif = dependency ('libexif',
-                   version: exif_ver,
-                   required: get_option ('enable-exif'))
-exempi = dependency ('exempi-2.0',
-                     version: exempi_ver,
-                     required: get_option ('enable-xmp'))
-selinux = dependency ('libselinux',
-                      version: selinux_ver,
-                      required: get_option ('enable-selinux'))
-
-if get_option ('enable-tracker')
-    tracker_sparql = dependency ('tracker-sparql-1.0')
-endif
-
 conf = configuration_data ()
 conf.set_quoted ('VERSION', meson.project_version ())
 conf.set_quoted ('PACKAGE_VERSION', meson.project_version ())
@@ -77,22 +63,34 @@ conf.set_quoted ('LOCALEDIR', join_paths (prefix, localedir))
 conf.set_quoted ('NAUTILUS_DATADIR', join_paths (datadir, 'nautilus'))
 conf.set_quoted ('NAUTILUS_EXTENSIONDIR', join_paths (prefix, extensiondir))
 
-if get_option ('enable-selinux')
-    conf.set10 ('HAVE_SELINUX', true)
-endif
-
 if get_option ('enable-desktop')
     conf.set10 ('ENABLE_DESKTOP', true)
 endif
 
+if get_option ('enable-exif')
+    exif = dependency ('libexif', version: exif_ver)
+    conf.set10 ('HAVE_EXIF', true)
+endif
+
 if get_option ('enable-packagekit')
     conf.set10 ('ENABLE_PACKAGEKIT', true)
 endif
 
+if get_option ('enable-selinux')
+    selinux = dependency ('libselinux', version: selinux_ver)
+    conf.set10 ('HAVE_SELINUX', true)
+endif
+
 if get_option ('enable-tracker')
+    tracker_sparql = dependency ('tracker-sparql-1.0')
     conf.set10 ('ENABLE_TRACKER', true)
 endif
 
+if get_option ('enable-xmp')
+    exempi = dependency ('exempi-2.0', version: exempi_ver)
+    conf.set10 ('HAVE_EXEMPI', true)
+endif
+
 configure_file (input: 'config.h.meson',
                 output: 'config.h',
                 configuration: conf)
diff --git a/src/meson.build b/src/meson.build
index d66e970..83723b9 100644
--- a/src/meson.build
+++ b/src/meson.build
@@ -280,6 +280,10 @@ nautilus_deps = [glib,
                  x11,
                  gmodule_no_export]
 
+if get_option ('enable-exif')
+    nautilus_deps += exif
+endif
+
 if get_option ('enable-tracker')
     nautilus_deps += tracker_sparql
 endif
@@ -288,6 +292,10 @@ if get_option ('enable-selinux')
     nautilus_deps += selinux
 endif
 
+if get_option ('enable-xmp')
+    nautilus_deps += exempi
+endif
+
 libnautilus = static_library ('nautilus',
                               libnautilus_sources,
                               dependencies: nautilus_deps,