+ * If this platform has <sys/acl.h>, acl_create(), acl_init(),
+ * acl_set_file(), and ACL_USER, we assume it has the rest of the
+ * POSIX.1e draft functions used in archive_read_extract.c.
+ */
+#if HAVE_SYS_ACL_H && HAVE_ACL_CREATE_ENTRY && HAVE_ACL_INIT && HAVE_ACL_SET_FILE
+#if HAVE_ACL_USER
+#define HAVE_POSIX_ACL 1
+#elif HAVE_ACL_TYPE_EXTENDED
+#define HAVE_DARWIN_ACL 1
+#endif
+#endif
+
+/*
+ * If this platform has <sys/acl.h>, acl_get(), facl_get(), acl_set(),
+ * facl_set() and types aclent_t and ace_t it uses Solaris-style ACL functions
+ */
+#if HAVE_SYS_ACL_H && HAVE_ACL_GET && HAVE_FACL_GET && HAVE_ACL_SET && HAVE_FACL_SET && HAVE_ACLENT_T && HAVE_ACE_T
+#define HAVE_SUN_ACL 1
+#endif
+
+/* Define if platform supports NFSv4 ACLs */
+#if (HAVE_POSIX_ACL && HAVE_ACL_TYPE_NFS4) || HAVE_SUN_ACL || HAVE_DARWIN_ACL
+#define HAVE_NFS4_ACL 1
+#endif
+
+/*