[ostree] build: Add --disable-documentation flag

[Colin Walters <walters src gnome org>]

commit 3c351a09e59eef9c754d119f94e780a71ab0797e
Author: Colin Walters <walters verbum org>
Date:   Fri Jan 13 16:30:39 2012 -0500

    build: Add --disable-documentation flag
    
    We may have xsltproc, but no DTDs.

 Makefile.am  |    2 +-
 configure.ac |   16 +++++++++++++---
 2 files changed, 14 insertions(+), 4 deletions(-)
---
diff --git a/Makefile.am b/Makefile.am
index 8869389..ddcf078 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -60,7 +60,7 @@ XML_FILES = \
 	${patsubst %.1,%.xml,${patsubst %.3,%.xml,${patsubst %.5,%.xml,${patsubst %.7,%.xml,${patsubst %.8,%.xml,$(MANPAGES)}}}}}
 EXTRA_DIST += $(XML_FILES)
 
-if HAVE_XSLTPROC
+if BUILD_DOCUMENTATION
 
 dist_man_MANS = $(MANPAGES)
 
diff --git a/configure.ac b/configure.ac
index b9f1ed7..bce1a45 100644
--- a/configure.ac
+++ b/configure.ac
@@ -30,6 +30,19 @@ LIBARCHIVE_DEPENDENCY="libarchive >= 2.8.0"
 
 PKG_CHECK_MODULES(OT_DEP_GIO_UNIX, $GIO_DEPENDENCY)
 
+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)
+
+
 AC_ARG_WITH(soup-gnome,
 	    AS_HELP_STRING([--without-soup-gnome], [Do not use libsoup-gnome (implies no pull support)]),
 	    :, with_soup_gnome=maybe)
@@ -65,9 +78,6 @@ AM_CONDITIONAL(USE_LIBARCHIVE, test $with_libarchive != no)
 
 AM_PATH_PYTHON([2.7])
 
-AC_PATH_PROG([XSLTPROC], [xsltproc])
-AM_CONDITIONAL(HAVE_XSLTPROC, test x"$XSLTPROC" != x)
-
 AC_CONFIG_FILES([
 Makefile
 ])