[PATCH nftables] doc: Include generated man pages in dist tarball

[Matt Turner <mattst88@gmail.com>]

Most projects ship pre-generated man pages in the distribution tarball
so that builders don't need the documentation tools installed, similar
to how bison-generated sources are included.

To do this, we conditionalize the presence check of a2x on whether nft.8
already exists in the source directory, as it would exist if included in
the distribution tarball.

Secondly, we move the 'if BUILD_MAN' conditional to around the man page
generation rules. This ensures that the man pages are unconditionally
installed. Also only add the man pages to CLEANFILES if their generation
is enabled.

Signed-off-by: Matt Turner <mattst88@gmail.com>
---
 configure.ac    |  2 +-
 doc/Makefile.am | 17 ++++++++---------
 2 files changed, 9 insertions(+), 10 deletions(-)

diff --git a/configure.ac b/configure.ac
index 6a25eeb3..a04d94bc 100644
--- a/configure.ac
+++ b/configure.ac
@@ -50,7 +50,7 @@ AC_EXEEXT
 AC_DISABLE_STATIC
 CHECK_GCC_FVISIBILITY
 
-AS_IF([test "x$enable_man_doc" = "xyes"], [
+AS_IF([test "x$enable_man_doc" = "xyes" -a ! -f "${srcdir}/doc/nft.8"], [
        AC_CHECK_PROG(A2X, [a2x], [a2x], [no])
        AS_IF([test "$A2X" = "no"],
 	     [AC_MSG_ERROR([a2x not found, please install asciidoc])])
diff --git a/doc/Makefile.am b/doc/Makefile.am
index f0958b33..6bd90aa6 100644
--- a/doc/Makefile.am
+++ b/doc/Makefile.am
@@ -1,6 +1,4 @@
-if BUILD_MAN
 man_MANS = nft.8 libnftables-json.5 libnftables.3
-endif
 
 A2X_OPTS_MANPAGE = -L --doctype manpage --format manpage -D ${builddir}
 
@@ -13,6 +11,12 @@ ASCIIDOC_INCLUDES = \
        statements.txt
 ASCIIDOCS = ${ASCIIDOC_MAIN} ${ASCIIDOC_INCLUDES}
 
+EXTRA_DIST = ${ASCIIDOCS} ${man_MANS} libnftables-json.adoc libnftables.adoc
+
+CLEANFILES = \
+	*~
+
+if BUILD_MAN
 nft.8: ${ASCIIDOCS}
 	${AM_V_GEN}${A2X} ${A2X_OPTS_MANPAGE} $<
 
@@ -22,10 +26,5 @@ nft.8: ${ASCIIDOCS}
 .adoc.5:
 	${AM_V_GEN}${A2X} ${A2X_OPTS_MANPAGE} $<
 
-EXTRA_DIST = ${ASCIIDOCS} libnftables-json.adoc libnftables.adoc
-
-CLEANFILES = \
-	nft.8 \
-	libnftables-json.5 \
-	libnftables.3 \
-	*~
+CLEANFILES += ${man_MANS}
+endif
-- 
2.24.1