X-Git-Url: https://git.dogcows.com/gitweb?a=blobdiff_plain;f=src%2Fstlplus%2Fpersistence%2Fpersistent_xref.hpp;fp=src%2Fstlplus%2Fpersistence%2Fpersistent_xref.hpp;h=c41e28d732d3ae67debda7648f7a9e53d58cdadd;hb=6b0a0d0efafe34d48ab344fca3b479553bd4e62c;hp=0000000000000000000000000000000000000000;hpb=85783316365181491a3e3c0c63659972477cebba;p=chaz%2Fyoink

diff --git a/src/stlplus/persistence/persistent_xref.hpp b/src/stlplus/persistence/persistent_xref.hpp
new file mode 100644
index 0000000..c41e28d
--- /dev/null
+++ b/src/stlplus/persistence/persistent_xref.hpp
@@ -0,0 +1,48 @@
+#ifndef STLPLUS_PERSISTENT_XREF
+#define STLPLUS_PERSISTENT_XREF
+////////////////////////////////////////////////////////////////////////////////
+
+//   Author:    Andy Rushton
+//   Copyright: (c) Southampton University 1999-2004
+//              (c) Andy Rushton           2004-2009
+//   License:   BSD License, see ../docs/license.html
+
+//   Persistence for cross-references to persistent objects
+
+//   A cross-reference is a pointer to an object that has definitely been dumped
+//   already by one of dump_pointer, dump_interface or dump_callback, i.e. by
+//   one of the dump routines for pointers to objects.
+
+//   These are typically used in data structures as back-pointers or pointers
+//   between nodes.
+
+//   For example, you may have a tree with cross links. Dump the tree as the
+//   primary data structure first, then dump the cross links as cross-references
+//   afterwards. The whole tree must be dumped before any cross-references to
+//   ensure that all cross-references are known to the persistence system.
+
+//   These functions will throw an exception if the cross-reference points to
+//   something not dumped before.
+
+////////////////////////////////////////////////////////////////////////////////
+#include "persistence_fixes.hpp"
+#include "persistent_contexts.hpp"
+
+////////////////////////////////////////////////////////////////////////////////
+
+namespace stlplus
+{
+
+  template<typename T>
+  void dump_xref(dump_context&, const T* const data)
+    throw(persistent_dump_failed);
+
+  template<typename T>
+  void restore_xref(restore_context&, T*& data)
+    throw(persistent_restore_failed);
+
+} // end namespace stlplus
+
+  ////////////////////////////////////////////////////////////////////////////////
+#include "persistent_xref.tpp"
+#endif