388 lines
14 KiB
C++
388 lines
14 KiB
C++
/***************************************************************************
|
|
**
|
|
** Copyright (C) 2013 BlackBerry Limited. All rights reserved.
|
|
** 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.
|
|
**
|
|
**
|
|
** $QT_END_LICENSE$
|
|
**
|
|
****************************************************************************/
|
|
|
|
#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.
|
|
|
|
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::system().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_LINUX_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 '+' 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
|
|
|
|
If you always use the same file you do not need to use QFileSelector.
|
|
|
|
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.
|
|
|
|
Selectors normally available are
|
|
\list
|
|
\li platform, one of: android, blackberry, ios, windows, osx, linux, generic_unix or unknown.
|
|
\li locale, same as QLocale::system().name().
|
|
\endlist
|
|
|
|
Further selectors will be added from the QT_FILE_SELECTORS environment variable, which when
|
|
set should be a set of colon (semi-colon on windows) 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. 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.
|
|
|
|
Additionally you can add extra selectors at runtime to customize behavior further. 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.
|
|
|
|
When multiple selectors could be applied to the same file, the first matching selector is chosen.
|
|
The order selectors are checked in are:
|
|
|
|
1. Selectors set via setExtraSelectors(), in the order they are in the list
|
|
2. Selectors in the QT_FILE_SELECTORS environment variable, from left to right
|
|
3. Locale
|
|
4. Platform
|
|
|
|
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 +admin/background.png will be chosen
|
|
on windows when the admin selector is set, and +windows/background.png will be chosen on
|
|
windows when the admin selector is not set. On linux, the +admin/+linux/background.png will be
|
|
chosen when admin is set, and the +linux/background.png when it is not.
|
|
|
|
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.
|
|
*/
|
|
|
|
/*!
|
|
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 QString qrcScheme()
|
|
{
|
|
return QStringLiteral("qrc");
|
|
}
|
|
|
|
/*!
|
|
This is a convenience version of select operating on QUrls. 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 (filePath.scheme() != qrcScheme() && !filePath.isLocalFile())
|
|
return filePath;
|
|
QUrl ret(filePath);
|
|
if (filePath.scheme() == qrcScheme()) {
|
|
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 (!qgetenv(env_override).isEmpty())
|
|
return;
|
|
|
|
sharedData->staticSelectors << sharedData->preloadedStatics; //Potential for static selectors from other modules
|
|
|
|
// TODO: Update on locale changed?
|
|
sharedData->staticSelectors << QLocale::system().name();
|
|
|
|
sharedData->staticSelectors << platformSelectors();
|
|
}
|
|
|
|
QStringList QFileSelectorPrivate::platformSelectors()
|
|
{
|
|
QStringList ret;
|
|
#if defined(Q_OS_WIN)
|
|
ret << QStringLiteral("windows");
|
|
# if defined(Q_OS_WINCE)
|
|
ret << QStringLiteral("wince");
|
|
# endif
|
|
#elif defined(Q_OS_UNIX)
|
|
ret << QStringLiteral("unix");
|
|
# if defined(Q_OS_LINUX_ANDROID)
|
|
ret << QStringLiteral("android");
|
|
# elif defined(Q_OS_BLACKBERRY)
|
|
ret << QStringLiteral("blackberry");
|
|
# elif defined(Q_OS_QNX)
|
|
ret << QStringLiteral("qnx");
|
|
# elif defined(Q_OS_IOS)
|
|
ret << QStringLiteral("ios");
|
|
# elif defined(Q_OS_LINUX)
|
|
ret << QStringLiteral("linux");
|
|
# elif defined(Q_OS_MAC)
|
|
ret << QStringLiteral("mac");
|
|
# else
|
|
struct utsname u;
|
|
if (uname(&u) != -1)
|
|
ret << QString::fromLatin1(u.sysname).toLower();
|
|
# endif
|
|
#endif
|
|
return ret;
|
|
}
|
|
|
|
void QFileSelectorPrivate::addStatics(const QStringList &statics)
|
|
{
|
|
QMutexLocker locker(&sharedDataMutex);
|
|
sharedData->preloadedStatics << statics;
|
|
}
|
|
|
|
QT_END_NAMESPACE
|
|
|
|
#include "moc_qfileselector.cpp"
|