diff --git a/include/haproxy/buf.h b/include/haproxy/buf.h
index 1136a6a9b..e98161ebe 100644
--- a/include/haproxy/buf.h
+++ b/include/haproxy/buf.h
@@ -1027,6 +1027,14 @@ static inline unsigned int br_count(const struct buffer *r)
 		return r->data + r->size - r->head;
 }
 
+/* Returns true if a single buffer is assigned */
+static inline unsigned int br_single(const struct buffer *r)
+{
+	BUG_ON_HOT(r->area != BUF_RING.area);
+
+	return r->data == r->head;
+}
+
 /* Returns the index of the ring's head buffer */
 static inline unsigned int br_head_idx(const struct buffer *r)
 {