-void sha1_init(sha1_context *hd);
-void sha1_update(sha1_context *hd, const byte *inbuf, uns inlen);
+void sha1_init(sha1_context *hd); /** Initialize new algorithm run in the @hd context. **/
+/**
+ * Push another @inlen bytes of data pointed to by @inbuf onto the
+ * SHA1 hash currently in @hd. You can call this any times you want on
+ * the same hash (and you do not need to reinitialize it by
+ * @sha1_init()). It has the same effect as concatenating all the data
+ * together and passing them at once.
+ */
+void sha1_update(sha1_context *hd, const byte *inbuf, uint inlen);
+/**
+ * No more @sha1_update() calls will be done. This terminates the hash
+ * and returns a pointer to it.
+ *
+ * Note that the pointer points into data in the @hd context. If it ceases
+ * to exist, the pointer becomes invalid.
+ *
+ * To convert the hash to its usual hexadecimal representation, see
+ * <<string:mem_to_hex()>>.
+ */