Add g_compute_hmac_for_bytes()

As an introspection-friendly GBytes variant of g_compute_hmac_for_data()

https://bugzilla.gnome.org/show_bug.cgi?id=765338

docs/reference/glib/glib-sections.txt

@@ -3011,6 +3011,7 @@ g_hmac_get_digest
 <SUBSECTION>
 g_compute_hmac_for_data
 g_compute_hmac_for_string
+g_compute_hmac_for_bytes
 </SECTION>
 
 <SECTION>

glib/ghmac.c

@@ -370,6 +370,42 @@ g_compute_hmac_for_data (GChecksumType  digest_type,
   return retval;
 }
 
+/**
+ * g_compute_hmac_for_bytes:
+ * @digest_type: a #GChecksumType to use for the HMAC
+ * @key: the key to use in the HMAC
+ * @data: binary blob to compute the HMAC of
+ *
+ * Computes the HMAC for a binary @data. This is a
+ * convenience wrapper for g_hmac_new(), g_hmac_get_string()
+ * and g_hmac_unref().
+ *
+ * The hexadecimal string returned will be in lower case.
+ *
+ * Returns: the HMAC of the binary data as a string in hexadecimal.
+ *   The returned string should be freed with g_free() when done using it.
+ *
+ * Since: 2.50
+ */
+gchar *
+g_compute_hmac_for_bytes (GChecksumType  digest_type,
+                          GBytes        *key,
+                          GBytes        *data)
+{
+  gconstpointer byte_data;
+  gsize length;
+  gconstpointer key_data;
+  gsize key_len;
+
+  g_return_val_if_fail (data != NULL, NULL);
+  g_return_val_if_fail (key != NULL, NULL);
+
+  byte_data = g_bytes_get_data (data, &length);
+  key_data = g_bytes_get_data (key, &key_len);
+  return g_compute_hmac_for_data (digest_type, key_data, key_len, byte_data, length);
+}
+
+
 /**
  * g_compute_hmac_for_string:
  * @digest_type: a #GChecksumType to use for the HMAC

glib/ghmac.h

@@ -72,6 +72,11 @@ gchar                *g_compute_hmac_for_string     (GChecksumType  digest_type,
                                                      gsize          key_len,
                                                      const gchar   *str,
                                                      gssize         length);
+GLIB_AVAILABLE_IN_2_50
+gchar               *g_compute_hmac_for_bytes       (GChecksumType  digest_type,
+                                                     GBytes        *key,
+                                                     GBytes        *data);
+
 
 G_END_DECLS