+/* smtp transport datachunk callback */
+
+#define tc_reap_prev BIT(0) /* Flags: reap previous SMTP cmd responses */
+#define tc_chunk_last BIT(1) /* annotate chunk SMTP cmd as LAST */
+
+struct transport_context;
+typedef int (*tpt_chunk_cmd_cb)(int fd, struct transport_context * tctx,
+ unsigned len, unsigned flags);
+
+/* Structure for information about a delivery-in-progress */
+
+typedef struct transport_context {
+ transport_instance * tblock; /* transport */
+ struct address_item * addr;
+ uschar * check_string; /* string replacement */
+ uschar * escape_string;
+ int options; /* output processing topt_* */
+
+ /* items below only used with option topt_use_bdat */
+ tpt_chunk_cmd_cb chunk_cb; /* per-datachunk callback */
+ void * smtp_context;
+} transport_ctx;
+
+
+
+typedef struct {
+ uschar *request;
+ uschar *require;
+} dnssec_domains;