[serialize] Implement linking

Untested!

diff --git a/src/hb-serialize.hh b/src/hb-serialize.hh
index ab07080..451afc3 100644 (file)
--- a/src/hb-serialize.hh
+++ b/src/hb-serialize.hh
@@ -67,7 +67,7 @@ struct hb_serialize_context_t
     struct link_t
     {
       bool wide: 1;
-      unsigned offset : 31;
+      unsigned position : 31;
       objidx_t objidx;
     };
 
@@ -220,7 +220,32 @@ struct hb_serialize_context_t
 
   void link ()
   {
-    // XXX
+    assert (!current.length);
+
+    for (auto obj_it = packed.iter (); obj_it; ++obj_it)
+    {
+      const object_t &parent = *obj_it;
+
+      for (auto link_it = parent.links.iter (); link_it; ++link_it)
+      {
+        const object_t::link_t &link = *link_it;
+       const object_t &child = packed[link.objidx];
+       unsigned offset = child.head - parent.head;
+
+       if (link.wide)
+       {
+         auto &off = * ((BEInt<uint32_t, 4> *) (parent.head + offset));
+         off = offset;
+         propagate_error (off == offset);
+       }
+       else
+       {
+         auto &off = * ((BEInt<uint16_t, 2> *) (parent.head + offset));
+         off = offset;
+         propagate_error (off == offset);
+       }
+      }
+    }
   }
 
   unsigned int length () const { return this->head - current.tail ().head; }