Add internal hb_buffer_t::get_scratch_buffer()

src/hb-buffer-private.hh

@@ -135,6 +135,8 @@ struct _hb_buffer_t {
   { return likely (size <= allocated) ? TRUE : enlarge (size); }
 
   HB_INTERNAL bool make_room_for (unsigned int num_in, unsigned int num_out);
+
+  HB_INTERNAL void *get_scratch_buffer (unsigned int *size);
 };
 
 

src/hb-buffer.cc

@@ -135,6 +135,16 @@ hb_buffer_t::make_room_for (unsigned int num_in,
   return TRUE;
 }
 
+void *
+hb_buffer_t::get_scratch_buffer (unsigned int *size)
+{
+  have_output = FALSE;
+  have_positions = FALSE;
+  out_len = 0;
+  *size = allocated * sizeof (pos[0]);
+  return pos;
+}
+
 
 /* HarfBuzz-Internal API */