changes to autoconf tests and configuration.c to use correct nanoseco…

…nds struct element depending on which is available, if any.

configure.ac

@@ -29,6 +29,9 @@ AM_MAINTAINER_MODE([disable])
 # Checks for libraries.
 AC_CHECK_LIB([ev], [ev_default_loop], [], AC_MSG_ERROR([Cannot find libev headers.]))
 AC_CHECK_LIB([ssl], [SSL_CTX_free], [], AC_MSG_ERROR([Cannot find libssl headers.]))
+AC_CHECK_MEMBERS([struct stat.st_mtim, struct stat.st_mtimespec], [nsec_avail="true"], [])
+AM_CONDITIONAL(NSEC_AVAIL, [test "x$nsec_avail" == xtrue])
+AM_COND_IF(NSEC_AVAIL, [], AC_MSG_WARN([Nanosecond resolution not available from struct stat]))
 
 AC_ARG_ENABLE(sessioncache,
     AC_HELP_STRING([--enable-sessioncache],

src/configuration.c

@@ -423,8 +423,13 @@ config_param_pem_file(char *filename, struct cfg_cert_file **cfptr)
 	ALLOC_OBJ(cert, CFG_CERT_FILE_MAGIC);
 	AN(cert);
 	config_assign_str(&cert->filename, filename);
-	cert->mtim = st.st_mtim.tv_sec
-	    + st.st_mtim.tv_nsec * 1e-9;
+	cert->mtim = st.st_mtime;
+#if defined(HAVE_STRUCT_STAT_ST_MTIM)
+	cert->mtim += st.st_mtim.tv_nsec * 1e-9;
+#elif defined(HAVE_STRUCT_STAT_ST_MTIMESPEC)
+	cert->mtim += st.st_mtimespec.tv_nsec * 1e-9;
+#endif
+
 
 	*cfptr = cert;
 	return (1);