build: check for missing feature files

linux/dccp.h is unlikely to be installed before 2.6.18 (which was
when headers_install was introduced), and does not exist at all
before 2.6.14. Add a compile-time check to skip compilation of
libxt_dccp in case this was detected.

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>

diff --git a/configure.ac b/configure.ac
index e718effc1188b6a0966f5f957c369aee04f347d2..d063605e39b7277fb6b4221c4918efbed09d7cdb 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -39,6 +39,14 @@ AC_ARG_ENABLE([libipq],
        AS_HELP_STRING([--enable-libipq], [Build and install libipq]))
 
 AC_CHECK_HEADER([netinet/ip6.h], [], [AC_MSG_ERROR(but we need that for IPv6)])
+AC_CHECK_HEADER([linux/dccp.h])
+
+blacklist_modules="";
+if test "$ac_cv_header_linux_dccp_h" != "yes"; then
+       blacklist_modules="$blacklist_modules dccp";
+fi;
+AC_SUBST([blacklist_modules])
+
 AM_CONDITIONAL([ENABLE_STATIC], [test "$enable_static" == "yes"])
 AM_CONDITIONAL([ENABLE_SHARED], [test "$enable_shared" == "yes"])
 AM_CONDITIONAL([ENABLE_DEVEL], [test "$enable_devel" == "yes"])

diff --git a/extensions/GNUmakefile.in b/extensions/GNUmakefile.in
index 941957448ce35e227508c5737db9a23f50ed8f60..8d44e4e1d93ad7683037219eb4a002269fec4d58 100644 (file)
--- a/extensions/GNUmakefile.in
+++ b/extensions/GNUmakefile.in
@@ -37,6 +37,9 @@ endif
 pfx_build_mod := $(patsubst ${srcdir}/libxt_%.c,%,$(wildcard ${srcdir}/libxt_*.c))
 pf4_build_mod := $(patsubst ${srcdir}/libipt_%.c,%,$(wildcard ${srcdir}/libipt_*.c))
 pf6_build_mod := $(patsubst ${srcdir}/libip6t_%.c,%,$(wildcard ${srcdir}/libip6t_*.c))
+pfx_build_mod := $(filter-out @blacklist_modules@,${pfx_build_mod})
+pf4_build_mod := $(filter-out @blacklist_modules@,${pf4_build_mod})
+pf6_build_mod := $(filter-out @blacklist_modules@,${pf6_build_mod})
 pfx_objs      := $(patsubst %,libxt_%.o,${pfx_build_mod})
 pf4_objs      := $(patsubst %,libipt_%.o,${pf4_build_mod})
 pf6_objs      := $(patsubst %,libip6t_%.o,${pf6_build_mod})