[gnome-control-center] build: Add --disable-documentation option

[Colin Walters <walters src gnome org>]

commit fdad89f85205a37707649ea70514ae34774f33ce
Author: Colin Walters <walters verbum org>
Date:   Mon Aug 6 18:19:24 2012 -0400

    build: Add --disable-documentation option
    
    For embedded systems, it's pointless to build the docs if they're not
    going to be used/shown.
    
    Also, for gnome-ostree right now I don't have the Docbook
    infrastructure set up.

 Makefile.am  |    5 ++++-
 configure.ac |   12 +++++++++++-
 2 files changed, 15 insertions(+), 2 deletions(-)
---
diff --git a/Makefile.am b/Makefile.am
index e57fbb8..0e05b41 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -1,6 +1,9 @@
 ACLOCAL_AMFLAGS = -I m4 ${ACLOCAL_FLAGS}
 
-SUBDIRS = po shell panels man
+SUBDIRS = po shell panels
+if BUILD_DOCUMENTATION
+SUBDIRS += man
+endif
 DIST_SUBDIRS = po shell panels man
 
 MAINTAINERCLEANFILES = \
diff --git a/configure.ac b/configure.ac
index 34f9095..020f694 100644
--- a/configure.ac
+++ b/configure.ac
@@ -35,7 +35,17 @@ x_libs="$X_PRE_LIBS $X_LIBS -lX11 $X_EXTRA_LIBS"
 
 AC_PATH_PROG([GLIB_MKENUMS],[glib-mkenums])
 
-AC_PATH_PROG([XSLTPROC], [xsltproc])
+AC_ARG_ENABLE(documentation,
+              AC_HELP_STRING([--enable-documentation],
+                             [build documentation]),,
+              enable_documentation=yes)
+if test x$enable_documentation = xyes; then
+   AC_PATH_PROG([XSLTPROC], [xsltproc])
+   if test x$XSLTPROC = x; then
+      AC_MSG_ERROR([xsltproc is required to build documentation])
+   fi
+fi
+AM_CONDITIONAL(BUILD_DOCUMENTATION, test x$enable_documentation = xyes)
 
 dnl Region panel
 savecppflags=$CPPFLAGS