[gnome-themes-standard] Add an option to disable building of gtk3 engines

[Johan Dahlin <johan src gnome org>]

commit 38c2ad82eeac5e923001352f2d318f2dba43fb05
Author: Johan Dahlin <johan gnome org>
Date:   Mon May 14 16:55:08 2012 -0300

    Add an option to disable building of gtk3 engines
    
    This makes it possible only build & install without depending on
    Gtk+ 3.0 which is useful for shipping Gtk+2.x applications.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=676045

 configure.ac                    |   15 ++++++++++++---
 src/Makefile.am                 |    6 +++++-
 themes/Adwaita/Makefile.am      |    6 +++++-
 themes/HighContrast/Makefile.am |    6 +++++-
 4 files changed, 27 insertions(+), 6 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index 97821f9..a39d1b7 100644
--- a/configure.ac
+++ b/configure.ac
@@ -28,11 +28,20 @@ AC_SUBST(GETTEXT_PACKAGE)
 AC_DEFINE_UNQUOTED([GETTEXT_PACKAGE],["$GETTEXT_PACKAGE"],[Gettext package])
 AM_GLIB_GNU_GETTEXT
 
+AC_ARG_ENABLE([gtk3-engines],
+              AC_HELP_STRING([--disable-gtk3-engines],
+                             [Disable Gtk+ 3.x engines [default=no]]),
+              enable_gtk3=$enableval,
+              enable_gtk3=yes)
+AC_MSG_CHECKING([building gtk3 engines])
+AM_CONDITIONAL(GTK3, test "x$enable_gtk3" = "xyes")
+AC_MSG_RESULT([$enable_gtk3])
 GTK_VERSION_REQUIRED=3.3.14
 
-PKG_CHECK_MODULES([DEPENDENCIES], [gtk+-3.0 >= $GTK_VERSION_REQUIRED librsvg-2.0])
-PKG_CHECK_MODULES([HIGHCONTRAST], [cairo gio-2.0 gdk-pixbuf-2.0 gdk-3.0])
-
+if test "x$enable_gtk3" = "xyes"; then
+  PKG_CHECK_MODULES([DEPENDENCIES], [gtk+-3.0 >= $GTK_VERSION_REQUIRED librsvg-2.0])
+  PKG_CHECK_MODULES([HIGHCONTRAST], [cairo gio-2.0 gdk-pixbuf-2.0 gdk-3.0])
+fi
 AC_SUBST(DEPENDENCIES_CFLAGS)
 AC_SUBST(DEPENDENCIES_LIBS)
 
diff --git a/src/Makefile.am b/src/Makefile.am
index 4af67bb..328ed68 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -1,5 +1,9 @@
 enginedir = $(libdir)/gtk-3.0/$(GTK_VERSION)/theming-engines
-engine_LTLIBRARIES = libadwaita.la
+
+engine_LTLIBRARIES =
+if GTK3
+engine_LTLIBRARIES += libadwaita.la
+endif
 
 assetsdir = $(datadir)/themes/Adwaita/gtk-3.0/assets
 
diff --git a/themes/Adwaita/Makefile.am b/themes/Adwaita/Makefile.am
index 7520ac9..50d98d2 100644
--- a/themes/Adwaita/Makefile.am
+++ b/themes/Adwaita/Makefile.am
@@ -1,4 +1,8 @@
-SUBDIRS = backgrounds cursors gtk-3.0 metacity-1 gtk-2.0
+SUBDIRS = backgrounds cursors metacity-1 gtk-2.0
+
+if GTK3
+SUBDIRS += gtk-3.0
+endif
 
 THEME_NAME=Adwaita
 THEME_IN_FILES=index.theme.in
diff --git a/themes/HighContrast/Makefile.am b/themes/HighContrast/Makefile.am
index 97ca464..bd8da43 100644
--- a/themes/HighContrast/Makefile.am
+++ b/themes/HighContrast/Makefile.am
@@ -11,7 +11,11 @@ themedir = $(datadir)/themes/$(THEME_NAME)
 
 theme_DATA = index.theme
 
-noinst_PROGRAMS = create-highcontrast
+noinst_PROGRAMS =
+if GTK3
+noinst_PROGRAMS += create-highcontrast
+endif
+
 create_highcontrast_SOURCES = create-highcontrast.c
 create_highcontrast_CFLAGS = $(HIGHCONTRAST_CFLAGS)
 create_highcontrast_LDADD = $(HIGHCONTRAST_LIBS) -lm