Add lazy pointer support

Built-in support is provided for raw, auto, and tr1 shared/weak pointers.
New test: common/lazy-ptr.

1 files changed, 51 insertions, 0 deletions

diff --git a/odb/lazy-ptr-impl.txx b/odb/lazy-ptr-impl.txx
new file mode 100644
index 0000000..c3055c9
--- /dev/null
+++ b/odb/lazy-ptr-impl.txx
@@ -0,0 +1,51 @@
+// file      : odb/lazy-ptr-impl.txx
+// author    : Boris Kolpackov <boris@codesynthesis.com>
+// copyright : Copyright (c) 2009-2010 Code Synthesis Tools CC
+// license   : GNU GPL v2; see accompanying LICENSE file
+
+#include <odb/database.hxx>
+
+namespace odb
+{
+  //
+  // lazy_ptr_base
+  //
+
+  template <typename T>
+  void lazy_ptr_base::
+  free (void* p)
+  {
+    delete static_cast<T*> (p);
+  }
+
+  template <typename T>
+  void* lazy_ptr_base::
+  copy (const void* p)
+  {
+    return new T (*static_cast<const T*> (p));
+  }
+
+  //
+  // lazy_ptr_impl
+  //
+
+  template <typename T>
+  template <typename O>
+  inline typename object_traits<O>::pointer_type lazy_ptr_impl<T>::
+  load (bool reset)
+  {
+    typedef typename object_traits<T>::id_type id_type;
+    typedef typename object_traits<T>::pointer_type pointer_type;
+
+    const id_type& id (*static_cast<const id_type*> (id_));
+    pointer_type p (db_->load<T> (id));
+
+    if (reset)
+      reset_id ();
+
+    // If you get a compile error pointing here, then you most likely
+    // used a wrong type as a template argument in the load() call.
+    //
+    return p;
+  }
+}