Add support for transaction multiplexing

Also delay getting a connection until after we do all the sanity
checks (e.g., that there is no active transaction). Otherwise we
are running risk of getting blocked rather than throwing an
exception.

1 files changed, 5 insertions, 4 deletions

diff --git a/odb/tracer/transaction-impl.hxx b/odb/tracer/transaction-impl.hxx
index f926183..b92797b 100644
--- a/odb/tracer/transaction-impl.hxx
+++ b/odb/tracer/transaction-impl.hxx
@@ -20,18 +20,19 @@ namespace odb
   {
     class LIBODB_TRACER_EXPORT transaction_impl: public odb::transaction_impl
     {
-    protected:
-      friend class connection;
-      friend class transaction;
-
+    public:
       typedef tracer::database database_type;
 
+      transaction_impl (database_type&);
       transaction_impl (connection_ptr);
 
       virtual
       ~transaction_impl ();
 
       virtual void
+      start ();
+
+      virtual void
       commit ();
 
       virtual void