1 files changed, 116 insertions, 0 deletions
diff --git a/src/gui/accessible/qaccessiblecache.cpp b/src/gui/accessible/qaccessiblecache.cpp
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+/****************************************************************************
+**
+** Copyright (C) 2013 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the QtGui module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Digia.  For licensing terms and
+** conditions see http://qt.digia.com/licensing.  For further information
+** use the contact form at http://qt.digia.com/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Digia gives you certain additional
+** rights.  These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3.0 as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU General Public License version 3.0 requirements will be
+** met: http://www.gnu.org/copyleft/gpl.html.
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qaccessiblecache_p.h"
+
+QT_BEGIN_NAMESPACE
+
+/*!
+    \class QAccessibleCache
+    \internal
+    \brief Maintains a cache of accessible interfaces.
+*/
+
+/*
+  The ID is always in the range [INT_MAX+1, UINT_MAX].
+  This makes it easy on windows to reserve the positive integer range
+  for the index of a child and not clash with the unique ids.
+*/
+QAccessible::Id QAccessibleCache::acquireId() const
+{
+    static const QAccessible::Id FirstId = QAccessible::Id(INT_MAX) + 1;
+    static QAccessible::Id lastUsedId = FirstId;
+
+    while (idToInterface.contains(lastUsedId)) {
+        if (lastUsedId == UINT_MAX) // (wrap back when when we reach UINT_MAX)
+            lastUsedId = FirstId;
+        else
+            ++lastUsedId;
+    }
+
+    return lastUsedId;
+}
+
+QAccessibleInterface *QAccessibleCache::interfaceForId(QAccessible::Id id) const
+{
+    return idToInterface.value(id);
+}
+
+QAccessible::Id QAccessibleCache::insert(QObject *object, QAccessibleInterface *iface) const
+{
+    Q_ASSERT(iface);
+    Q_UNUSED(object)
+
+    // object might be 0
+    Q_ASSERT(!objectToId.contains(object));
+    Q_ASSERT_X(!idToInterface.values().contains(iface), "", "Accessible interface inserted into cache twice!");
+
+    QAccessible::Id id = acquireId();
+    QObject *obj = iface->object();
+    Q_ASSERT(object == obj);
+    if (obj) {
+        objectToId.insert(obj, id);
+        connect(obj, SIGNAL(destroyed(QObject *)), this, SLOT(objectDestroyed(QObject *)));
+    }
+    idToInterface.insert(id, iface);
+    return id;
+}
+
+void QAccessibleCache::objectDestroyed(QObject* obj)
+{
+    QAccessible::Id id = objectToId.value(obj);
+    if (id) {
+        Q_ASSERT_X(idToInterface.contains(id), "", "QObject with accessible interface deleted, where interface not in cache!");
+        deleteInterface(id, obj);
+    }
+}
+
+void QAccessibleCache::deleteInterface(QAccessible::Id id, QObject *obj)
+{
+    QAccessibleInterface *iface = idToInterface.take(id);
+    if (!obj)
+        obj = iface->object();
+    if (obj)
+        objectToId.remove(obj);
+    delete iface;
+}
+
+QT_END_NAMESPACE