Return number of calls made from migrate_data()

Can be useful for debugging/tracing.

2 files changed, 13 insertions, 6 deletions

diff --git a/odb/schema-catalog.cxx b/odb/schema-catalog.cxx
index 8a5ce71..15cdcb9 100644
--- a/odb/schema-catalog.cxx
+++ b/odb/schema-catalog.cxx
@@ -194,13 +194,13 @@ namespace odb
     db.schema_version_migration (v, m == migrate_pre, name);
   }
 
-  void schema_catalog::
+  size_t schema_catalog::
   migrate_data (database& db, schema_version v, const string& name)
   {
     if (v == 0)
     {
       if (!db.schema_migration ())
-        return;
+        return 0;
 
       v = db.schema_version ();
     }
@@ -209,16 +209,22 @@ namespace odb
     data_map::const_iterator i (c.data.find (data_key (name, v)));
 
     if (i == c.data.end ())
-      return; // No data migration for this schema/version.
+      return 0; // No data migration for this schema/version.
 
-    const data_functions& df (i->second);
+    size_t r (0);
 
+    const data_functions& df (i->second);
     for (data_functions::const_iterator i (df.begin ()), e (df.end ());
          i != e; ++i)
     {
       if (i->id == id_common || i->id == db.id ())
+      {
         i->migrate (db);
+        r++;
+      }
     }
+
+    return r;
   }
 
   void schema_catalog::
diff --git a/odb/schema-catalog.hxx b/odb/schema-catalog.hxx
index 5af7c48..a58a2dc 100644
--- a/odb/schema-catalog.hxx
+++ b/odb/schema-catalog.hxx
@@ -10,6 +10,7 @@
 #include <odb/details/config.hxx> // ODB_CXX11
 
 #include <string>
+#include <cstddef> // std::size_t
 
 #ifdef ODB_CXX11
 #  include <functional> // std::function
@@ -63,9 +64,9 @@ namespace odb
     //
   public:
     // If version is 0, then use the current version and also check whether
-    // we are in migration.
+    // we are in migration. Returns the number of calls made.
     //
-    static void
+    static std::size_t
     migrate_data (database&,
                   schema_version = 0,
                   const std::string& name = "");