Oilpan: Prepare to move SQLResultSet and SQLResultSetRowList to oilpan heap.

Source/modules/webdatabase/SQLStatementBackend.cpp

Index: Source/modules/webdatabase/SQLStatementBackend.cpp
diff --git a/Source/modules/webdatabase/SQLStatementBackend.cpp b/Source/modules/webdatabase/SQLStatementBackend.cpp
index 9d65703d7a2f5a6c47b01db3c335bf113c24a83f..d0ab7e913d92dad4d5c8342f7400dc648844ab1b 100644
--- a/Source/modules/webdatabase/SQLStatementBackend.cpp
+++ b/Source/modules/webdatabase/SQLStatementBackend.cpp
@@ -84,13 +84,15 @@ SQLStatementBackend::SQLStatementBackend(PassOwnPtr<AbstractSQLStatement> fronte
     , m_arguments(arguments)
     , m_hasCallback(m_frontend->hasCallback())
     , m_hasErrorCallback(m_frontend->hasErrorCallback())
+    , m_resultSet(SQLResultSet::create())
     , m_permissions(permissions)
 {
     m_frontend->setBackend(this);
 }
 
-void SQLStatementBackend::trace(Visitor*)
+void SQLStatementBackend::trace(Visitor* visitor)
 {
+    visitor->trace(m_resultSet);
 }
 
 AbstractSQLStatement* SQLStatementBackend::frontend()
@@ -103,14 +105,14 @@ PassRefPtr<SQLError> SQLStatementBackend::sqlError() const
     return m_error;
 }
 
-PassRefPtr<SQLResultSet> SQLStatementBackend::sqlResultSet() const
+SQLResultSet* SQLStatementBackend::sqlResultSet() const
 {
-    return m_resultSet;
+    return m_resultSet->isValid() ? m_resultSet.get() : 0;
 }
 
 bool SQLStatementBackend::execute(DatabaseBackend* db)
 {
-    ASSERT(!m_resultSet);
+    ASSERT(!m_resultSet->isValid());
 
     // If we're re-running this statement after a quota violation, we need to clear that error now
     clearFailureDueToQuota();
@@ -161,13 +163,11 @@ bool SQLStatementBackend::execute(DatabaseBackend* db)
         }
     }
 
-    RefPtr<SQLResultSet> resultSet = SQLResultSet::create();
-
     // Step so we can fetch the column names.
     result = statement.step();
     if (result == SQLResultRow) {
         int columnCount = statement.columnCount();
-        SQLResultSetRowList* rows = resultSet->rows();
+        SQLResultSetRowList* rows = m_resultSet->rows();
 
         for (int i = 0; i < columnCount; i++)
             rows->addColumn(statement.getColumnName(i));
@@ -187,7 +187,7 @@ bool SQLStatementBackend::execute(DatabaseBackend* db)
     } else if (result == SQLResultDone) {
         // Didn't find anything, or was an insert
         if (db->lastActionWasInsert())
-            resultSet->setInsertId(database->lastInsertRowID());
+            m_resultSet->setInsertId(database->lastInsertRowID());
     } else if (result == SQLResultFull) {
         // Return the Quota error - the delegate will be asked for more space and this statement might be re-run
         setFailureDueToQuota(db);
@@ -205,23 +205,23 @@ bool SQLStatementBackend::execute(DatabaseBackend* db)
     // FIXME: If the spec allows triggers, and we want to be "accurate" in a different way, we'd use
     // sqlite3_total_changes() here instead of sqlite3_changed, because that includes rows modified from within a trigger
     // For now, this seems sufficient
-    resultSet->setRowsAffected(database->lastChanges());
+    m_resultSet->setRowsAffected(database->lastChanges());
 
-    m_resultSet = resultSet;
+    m_resultSet->setValid();

[haraken, 2014/03/25 07:55:30]

In my understanding, setValid() should be always coupled with setRowsAffected().
If so, shall we set m_valid to true in setRowsAffected()? Then setValid() won't
be necessary.

[tkent, 2014/03/25 08:40:32]

Right.  Done.

     db->reportExecuteStatementResult(0, -1, 0); // OK
     return true;
 }
 
 void SQLStatementBackend::setVersionMismatchedError(DatabaseBackend* database)
 {
-    ASSERT(!m_error && !m_resultSet);
+    ASSERT(!m_error && !m_resultSet->isValid());
     database->reportExecuteStatementResult(7, SQLError::VERSION_ERR, 0);
     m_error = SQLError::create(SQLError::VERSION_ERR, "current version of the database and `oldVersion` argument do not match");
 }
 
 void SQLStatementBackend::setFailureDueToQuota(DatabaseBackend* database)
 {
-    ASSERT(!m_error && !m_resultSet);
+    ASSERT(!m_error && !m_resultSet->isValid());
     database->reportExecuteStatementResult(8, SQLError::QUOTA_ERR, 0);
     m_error = SQLError::create(SQLError::QUOTA_ERR, "there was not enough remaining storage space, or the storage quota was reached and the user declined to allow more space");
 }