iOS: Add standard paths implementation for iOS

A standard paths implementation for iOS. The APIs used on iOS require
that the source file be "Objective-C++" (with a .MM extension), as
there are no APIs available in C++ for this. The implementation
complies with the latest documentation on standard paths.

Change-Id: I349d3c5d4ddb6fb1297a45dc9ae26b56ac528abb
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
Reviewed-by: David Faure <david.faure@kdab.com>

src/corelib/io/io.pri

@@ -135,6 +135,8 @@ win32 {
         mac {
             macx {
                 SOURCES += io/qstandardpaths_mac.cpp
+            } else:ios {
+                OBJECTIVE_SOURCES += io/qstandardpaths_ios.mm
             } else {
                 SOURCES += io/qstandardpaths_unix.cpp
             }

src/corelib/io/qstandardpaths_ios.mm

@@ -0,0 +1,135 @@
+/****************************************************************************
+**
+** Copyright (C) 2013 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the QtCore 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.
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#import <UIKit/UIKit.h>
+
+#include "qstandardpaths.h"
+
+#ifndef QT_NO_STANDARDPATHS
+
+QT_BEGIN_NAMESPACE
+
+static QString pathForDirectory(NSSearchPathDirectory directory)
+{
+    return QString::fromNSString(
+        [NSSearchPathForDirectoriesInDomains(directory, NSUserDomainMask, YES) lastObject]);
+}
+
+static QString bundlePath()
+{
+    return QString::fromNSString([[NSBundle mainBundle] bundlePath]);
+}
+
+QString QStandardPaths::writableLocation(StandardLocation type)
+{
+    QString location;
+
+    switch (type) {
+    case DesktopLocation:
+        location = pathForDirectory(NSDesktopDirectory);
+        break;
+    case DocumentsLocation:
+        location = pathForDirectory(NSDocumentDirectory);
+        break;
+    case FontsLocation:
+        location = bundlePath() + QLatin1String("/.fonts");
+        break;
+    case ApplicationsLocation:
+        location = pathForDirectory(NSApplicationDirectory);
+        break;
+    case MusicLocation:
+        location = pathForDirectory(NSMusicDirectory);
+        break;
+    case MoviesLocation:
+        location = pathForDirectory(NSMoviesDirectory);
+        break;
+    case PicturesLocation:
+        location = pathForDirectory(NSPicturesDirectory);
+        break;
+    case TempLocation:
+        location = QString::fromNSString(NSTemporaryDirectory());
+        break;
+    case HomeLocation:
+        location = bundlePath();
+        break;
+    case DataLocation:
+    case GenericDataLocation:
+        location = pathForDirectory(NSDocumentDirectory);
+        break;
+    case CacheLocation:
+    case GenericCacheLocation:
+        location = pathForDirectory(NSCachesDirectory);
+        break;
+    case ConfigLocation:
+        location = pathForDirectory(NSDocumentDirectory);
+        break;
+    case DownloadLocation:
+        location = pathForDirectory(NSDownloadsDirectory);
+        break;
+    default:
+        break;
+    }
+
+    switch (type) {
+    case RuntimeLocation:
+        break;
+    default:
+        // All other types must return something, so use the document directory
+        // as a reasonable fall-back (which will always exist).
+        if (location.isEmpty())
+            location = pathForDirectory(NSDocumentDirectory);
+        break;
+    }
+
+    return location;
+}
+
+QStringList QStandardPaths::standardLocations(StandardLocation type)
+{
+    QStringList dirs;
+    const QString localDir = writableLocation(type);
+    dirs.prepend(localDir);
+    return dirs;
+}
+
+QT_END_NAMESPACE
+
+#endif // QT_NO_STANDARDPATHS