Controls: copy QFileSelector from QtCore 3cae29b7

qtbase:src/corelib/io/ -> qtquickcontrols:src/imports/controls/
qfileselector.h -> qquickfileselector_p.h
qfileselector_p.h -> qquickfileselector_p_p.h
qfileselector.cpp -> qquickfileselector.cpp

Change-Id: Ib418b715a0578eeb8ac21c6f07e2e7378c0696ce
Reviewed-by: J-P Nurmi <jpnurmi@theqtcompany.com>

1 files changed, 393 insertions, 0 deletions

diff --git a/src/imports/controls/qquickfileselector.cpp b/src/imports/controls/qquickfileselector.cpp
new file mode 100644
index 00000000..85d9b0bf
--- /dev/null
+++ b/src/imports/controls/qquickfileselector.cpp
@@ -0,0 +1,393 @@
+/***************************************************************************
+**
+** Copyright (C) 2013 BlackBerry Limited. All rights reserved.
+** Contact: http://www.qt.io/licensing/
+**
+** This file is part of the QtCore module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL21$
+** 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 The Qt Company. For licensing terms
+** and conditions see http://www.qt.io/terms-conditions. For further
+** information use the contact form at http://www.qt.io/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 or version 3 as published by the Free
+** Software Foundation and appearing in the file LICENSE.LGPLv21 and
+** LICENSE.LGPLv3 included in the packaging of this file. Please review the
+** following information to ensure the GNU Lesser General Public License
+** requirements will be met: https://www.gnu.org/licenses/lgpl.html and
+** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** As a special exception, The Qt Company gives you certain additional
+** rights. These rights are described in The Qt Company LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qfileselector.h"
+#include "qfileselector_p.h"
+
+#include <QtCore/QFile>
+#include <QtCore/QDir>
+#include <QtCore/QMutex>
+#include <QtCore/QMutexLocker>
+#include <QtCore/QUrl>
+#include <QtCore/QFileInfo>
+#include <QtCore/QLocale>
+#include <QtCore/QDebug>
+
+QT_BEGIN_NAMESPACE
+
+//Environment variable to allow tooling full control of file selectors
+static const char env_override[] = "QT_NO_BUILTIN_SELECTORS";
+
+static const ushort selectorIndicator = '+';
+
+Q_GLOBAL_STATIC(QFileSelectorSharedData, sharedData);
+static QBasicMutex sharedDataMutex;
+
+QFileSelectorPrivate::QFileSelectorPrivate()
+    : QObjectPrivate()
+{
+}
+
+/*!
+    \class QFileSelector
+    \inmodule QtCore
+    \brief QFileSelector provides a convenient way of selecting file variants.
+    \since 5.2
+
+    QFileSelector is a convenience for selecting file variants based on platform or device
+    characteristics. This allows you to develop and deploy one codebase containing all the
+    different variants more easily in some circumstances, such as when the correct variant cannot
+    be determined during the deploy step.
+
+    \section1 Using QFileSelector
+
+    If you always use the same file you do not need to use QFileSelector.
+
+    Consider the following example usage, where you want to use different settings files on
+    different locales. You might select code between locales like this:
+
+    \code
+    QString defaultsBasePath = "data/";
+    QString defaultsPath = defaultsBasePath + "defaults.conf";
+    QString localizedPath = defaultsBasePath
+            + QString("%1/defaults.conf").arg(QLocale().name());
+    if (QFile::exists(localizedPath))
+        defaultsPath = localizedPath;
+    QFile defaults(defaultsPath);
+    \endcode
+
+    Similarly, if you want to pick a different data file based on target platform,
+    your code might look something like this:
+    \code
+    QString defaultsPath = "data/defaults.conf";
+#if defined(Q_OS_ANDROID)
+    defaultsPath = "data/android/defaults.conf";
+#elif defined(Q_OS_BLACKBERRY)
+    defaultsPath = "data/blackberry/defaults.conf";
+#elif defined(Q_OS_IOS)
+    defaultsPath = "data/ios/defaults.conf";
+#endif
+    QFile defaults(defaultsPath);
+    \endcode
+
+    QFileSelector provides a convenient alternative to writing such boilerplate code, and in the
+    latter case it allows you to start using an platform-specific configuration without a recompile.
+    QFileSelector also allows for chaining of multiple selectors in a convenient way, for example
+    selecting a different file only on certain combinations of platform and locale. For example, to
+    select based on platform and/or locale, the code is as follows:
+
+    \code
+    QFileSelector selector;
+    QFile defaultsFile(selector.select("data/defaults.conf"));
+    \endcode
+
+    The files to be selected are placed in directories named with a \c'+' and a selector name. In the above
+    example you could have the platform configurations selected by placing them in the following locations:
+    \code
+    data/defaults.conf
+    data/+android/defaults.conf
+    data/+blackberry/defaults.conf
+    data/+ios/+en_GB/defaults.conf
+    \endcode
+
+    To find selected files, QFileSelector looks in the same directory as the base file. If there are
+    any directories of the form +<selector> with an active selector, QFileSelector will prefer a file
+    with the same file name from that directory over the base file. These directories can be nested to
+    check against multiple selectors, for example:
+    \code
+    images/background.png
+    images/+android/+en_GB/background.png
+    images/+blackberry/+en_GB/background.png
+    \endcode
+    With those files available, you would select a different file on android and blackberry platforms,
+    but only if the locale was en_GB.
+
+    QFileSelector will not attempt to select if the base file does not exist. For error handling in
+    the case no valid selectors are present, it is recommended to have a default or error-handling
+    file in the base file location even if you expect selectors to be present for all deployments.
+
+    In a future version, some may be marked as deploy-time static and be moved during the
+    deployment step as an optimization. As selectors come with a performance cost, it is
+    recommended to avoid their use in circumstances involving performance-critical code.
+
+    \section1 Adding Selectors
+
+    Selectors normally available are
+    \list
+    \li platform, any of the following strings which match the platform the application is running
+        on (list not exhaustive): android, blackberry, ios, osx, darwin, mac, linux, wince, unix,
+        windows. On Linux, if it can be determined, the name of the distribution too, like debian,
+        fedora or opensuse.
+    \li locale, same as QLocale().name().
+    \endlist
+
+    Further selectors will be added from the \c QT_FILE_SELECTORS environment variable, which
+    when set should be a set of comma separated selectors. Note that this variable will only be
+    read once; selectors may not update if the variable changes while the application is running.
+    The initial set of selectors are evaluated only once, on first use.
+
+    You can also add extra selectors at runtime for custom behavior. These will be used in any
+    future calls to select(). If the extra selectors list has been changed, calls to select() will
+    use the new list and may return differently.
+
+    \section1 Conflict Resolution when Multiple Selectors Apply
+
+    When multiple selectors could be applied to the same file, the first matching selector is chosen.
+    The order selectors are checked in are:
+
+    \list 1
+    \li Selectors set via setExtraSelectors(), in the order they are in the list
+    \li Selectors in the \c QT_FILE_SELECTORS environment variable, from left to right
+    \li Locale
+    \li Platform
+    \endlist
+
+    Here is an example involving multiple selectors matching at the same time. It uses platform
+    selectors, plus an extra selector named "admin" is set by the application based on user
+    credentials. The example is sorted so that the lowest matching file would be chosen if all
+    selectors were present:
+
+    \code
+    images/background.png
+    images/+linux/background.png
+    images/+windows/background.png
+    images/+admin/background.png
+    images/+admin/+linux/background.png
+    \endcode
+
+    Because extra selectors are checked before platform the \c{+admin/background.png} will be chosen
+    on Windows when the admin selector is set, and \c{+windows/background.png} will be chosen on
+    Windows when the admin selector is not set.  On Linux, the \c{+admin/+linux/background.png} will be
+    chosen when admin is set, and the \c{+linux/background.png} when it is not.
+
+*/
+
+/*!
+    Create a QFileSelector instance. This instance will have the same static selectors as other
+    QFileSelector instances, but its own set of extra selectors.
+
+    If supplied, it will have the given QObject \a parent.
+*/
+QFileSelector::QFileSelector(QObject *parent)
+    : QObject(*(new QFileSelectorPrivate()), parent)
+{
+}
+
+/*!
+  Destroys this selector instance.
+*/
+QFileSelector::~QFileSelector()
+{
+}
+
+/*!
+   This function returns the selected version of the path, based on the conditions at runtime.
+   If no selectable files are present, returns the original \a filePath.
+
+   If the original file does not exist, the original \a filePath is returned. This means that you
+   must have a base file to fall back on, you cannot have only files in selectable sub-directories.
+
+   See the class overview for the selection algorithm.
+*/
+QString QFileSelector::select(const QString &filePath) const
+{
+    Q_D(const QFileSelector);
+    return d->select(filePath);
+}
+
+static bool isLocalScheme(const QString &file)
+{
+    bool local = file == QStringLiteral("qrc");
+#ifdef Q_OS_ANDROID
+    local |= file == QStringLiteral("assets");
+#endif
+    return local;
+}
+
+/*!
+   This is a convenience version of select operating on QUrl objects. If the scheme is not file or qrc,
+   \a filePath is returned immediately. Otherwise selection is applied to the path of \a filePath
+   and a QUrl is returned with the selected path and other QUrl parts the same as \a filePath.
+
+   See the class overview for the selection algorithm.
+*/
+QUrl QFileSelector::select(const QUrl &filePath) const
+{
+    Q_D(const QFileSelector);
+    if (!isLocalScheme(filePath.scheme()) && !filePath.isLocalFile())
+        return filePath;
+    QUrl ret(filePath);
+    if (isLocalScheme(filePath.scheme())) {
+        QString equivalentPath = QLatin1Char(':') + filePath.path();
+        QString selectedPath = d->select(equivalentPath);
+        ret.setPath(selectedPath.remove(0, 1));
+    } else {
+        ret = QUrl::fromLocalFile(d->select(ret.toLocalFile()));
+    }
+    return ret;
+}
+
+static QString selectionHelper(const QString &path, const QString &fileName, const QStringList &selectors)
+{
+    /* selectionHelper does a depth-first search of possible selected files. Because there is strict
+       selector ordering in the API, we can stop checking as soon as we find the file in a directory
+       which does not contain any other valid selector directories.
+    */
+    Q_ASSERT(path.isEmpty() || path.endsWith(QLatin1Char('/')));
+
+    foreach (const QString &s, selectors) {
+        QString prospectiveBase = path + QLatin1Char(selectorIndicator) + s + QLatin1Char('/');
+        QStringList remainingSelectors = selectors;
+        remainingSelectors.removeAll(s);
+        if (!QDir(prospectiveBase).exists())
+            continue;
+        QString prospectiveFile = selectionHelper(prospectiveBase, fileName, remainingSelectors);
+        if (!prospectiveFile.isEmpty())
+            return prospectiveFile;
+    }
+
+    // If we reach here there were no successful files found at a lower level in this branch, so we
+    // should check this level as a potential result.
+    if (!QFile::exists(path + fileName))
+        return QString();
+    return path + fileName;
+}
+
+QString QFileSelectorPrivate::select(const QString &filePath) const
+{
+    Q_Q(const QFileSelector);
+    QFileInfo fi(filePath);
+    // If file doesn't exist, don't select
+    if (!fi.exists())
+        return filePath;
+
+    QString ret = selectionHelper(fi.path().isEmpty() ? QString() : fi.path() + QLatin1Char('/'),
+            fi.fileName(), q->allSelectors());
+
+    if (!ret.isEmpty())
+        return ret;
+    return filePath;
+}
+
+/*!
+    Returns the list of extra selectors which have been added programmatically to this instance.
+*/
+QStringList QFileSelector::extraSelectors() const
+{
+    Q_D(const QFileSelector);
+    return d->extras;
+}
+
+/*!
+    Sets the \a list of extra selectors which have been added programmatically to this instance.
+
+    These selectors have priority over any which have been automatically picked up.
+*/
+void QFileSelector::setExtraSelectors(const QStringList &list)
+{
+    Q_D(QFileSelector);
+    d->extras = list;
+}
+
+/*!
+    Returns the complete, ordered list of selectors used by this instance
+*/
+QStringList QFileSelector::allSelectors() const
+{
+    Q_D(const QFileSelector);
+    QMutexLocker locker(&sharedDataMutex);
+    QFileSelectorPrivate::updateSelectors();
+    return d->extras + sharedData->staticSelectors;
+}
+
+void QFileSelectorPrivate::updateSelectors()
+{
+    if (!sharedData->staticSelectors.isEmpty())
+        return; //Already loaded
+
+    QLatin1Char pathSep(',');
+    QStringList envSelectors = QString::fromLatin1(qgetenv("QT_FILE_SELECTORS"))
+                                .split(pathSep, QString::SkipEmptyParts);
+    if (envSelectors.count())
+        sharedData->staticSelectors << envSelectors;
+
+    if (!qEnvironmentVariableIsEmpty(env_override))
+        return;
+
+    sharedData->staticSelectors << sharedData->preloadedStatics; //Potential for static selectors from other modules
+
+    // TODO: Update on locale changed?
+    sharedData->staticSelectors << QLocale().name();
+
+    sharedData->staticSelectors << platformSelectors();
+}
+
+QStringList QFileSelectorPrivate::platformSelectors()
+{
+    // similar, but not identical to QSysInfo::osType
+    QStringList ret;
+#if defined(Q_OS_WIN)
+    // can't fall back to QSysInfo because we need both "winphone" and "winrt" for the Windows Phone case
+    ret << QStringLiteral("windows");
+    ret << QSysInfo::kernelType();  // "wince" and "winnt"
+#  if defined(Q_OS_WINRT)
+    ret << QStringLiteral("winrt");
+#    if defined(Q_OS_WINPHONE)
+    ret << QStringLiteral("winphone");
+#    endif
+#  endif
+#elif defined(Q_OS_UNIX)
+    ret << QStringLiteral("unix");
+#  if !defined(Q_OS_ANDROID) && !defined(Q_OS_BLACKBERRY)
+    // we don't want "linux" for Android or "qnx" for Blackberry here
+    ret << QSysInfo::kernelType();
+#     ifdef Q_OS_MAC
+    ret << QStringLiteral("mac"); // compatibility, since kernelType() is "darwin"
+#     endif
+#  endif
+    QString productName = QSysInfo::productType();
+    if (productName != QLatin1String("unknown"))
+        ret << productName; // "opensuse", "fedora", "osx", "ios", "blackberry", "android"
+#endif
+    return ret;
+}
+
+void QFileSelectorPrivate::addStatics(const QStringList &statics)
+{
+    QMutexLocker locker(&sharedDataMutex);
+    sharedData->preloadedStatics << statics;
+}
+
+QT_END_NAMESPACE
+
+#include "moc_qfileselector.cpp"