build: make use of libbsd work even if a user override CFLAGS

`make CFLAGS=...` should work as expected.

diff --git a/configure.ac b/configure.ac
index 9743404e7fb229978bad30484bb2554be8fadeb0..f4c0a64a0eb0b53ca6a3f15331c0a1e474d91697 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -131,10 +131,14 @@ AC_FUNC_REALLOC
 AC_FUNC_FORK
 
 # Some functions can be in libbsd
-PKG_CHECK_MODULES([libbsd], [libbsd-overlay], [
-  CFLAGS="$CFLAGS $libbsd_CFLAGS"
-  LIBS="$LIBS $libbsd_LIBS"
-], [])
+PKG_CHECK_MODULES([libbsd], [libbsd-overlay], [], [:])
+_save_CFLAGS="$CFLAGS"
+_save_LIBS="$LIBS"
+CFLAGS="$CFLAGS $libbsd_CFLAGS"
+LIBS="$LIBS $libbsd_LIBS"
+LLDP_CFLAGS="$LLDP_CFLAGS $libbsd_CFLAGS"
+LLDP_LDFLAGS="$LLDP_LDFLAGS $libbsd_LIBS"
+
 # setproctitle may have an _init function
 AC_REPLACE_FUNCS([setproctitle])
 AC_CHECK_FUNCS([setproctitle_init])
@@ -159,6 +163,9 @@ AC_SEARCH_LIBS([res_init], resolv bind,
                [Define to indicate that res_init() exists]))
 m4_popdef([AC_LANG_CALL(C)])
 
+CFLAGS="$_save_CFLAGS"
+LIBS="$_save_LIBS"
+
 AC_CACHE_SAVE
 
 ## Unit tests wich check