diff --git a/include/haproxy/applet.h b/include/haproxy/applet.h
index 6eec621b4..2b1a5af7f 100644
--- a/include/haproxy/applet.h
+++ b/include/haproxy/applet.h
@@ -315,6 +315,15 @@ static inline size_t applet_input_data(const struct appctx *appctx)
 		return co_data(sc_oc(appctx_sc(appctx)));
 }
 
+/* Returns the amount of HTX data in the input buffer (see applet_get_inbuf) */
+static inline size_t applet_htx_input_data(const struct appctx *appctx)
+{
+	if (appctx->flags & APPCTX_FL_INOUT_BUFS)
+		return htx_used_space(htxbuf(&appctx->inbuf));
+	else
+		return co_data(sc_oc(appctx_sc(appctx)));
+}
+
 /* Skips <len> bytes from the input buffer (see applet_get_inbuf).
  *
  * This is useful when data have been read directly from the buffer. It is
@@ -354,6 +363,16 @@ static inline size_t applet_output_room(const struct appctx *appctx)
 		return channel_recv_max(sc_ic(appctx_sc(appctx)));
 }
 
+/* Returns the amout of space available at the HTX output buffer (see applet_get_outbuf).
+ */
+static inline size_t applet_htx_output_room(const struct appctx *appctx)
+{
+	if (appctx->flags & APPCTX_FL_INOUT_BUFS)
+		return htx_free_data_space(htxbuf(&appctx->outbuf));
+	else
+		return channel_recv_max(sc_ic(appctx_sc(appctx)));
+}
+
 /*Indicates that the applet have more data to deliver and it needs more room in
  * the output buffer to do so (see applet_get_outbuf).
  *