path: root/src/corelib/io/qstandardpaths.cpp

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#include "qstandardpaths.h"

#include <qdir.h>
#include <qfileinfo.h>
#include <qhash.h>
#include <qobject.h>
#include <qcoreapplication.h>

#ifndef QT_NO_STANDARDPATHS

QT_BEGIN_NAMESPACE

/*!
    \class QStandardPaths
    \brief The QStandardPaths class provides methods for accessing standard paths.
    \since 5.0

    This class contains functions to query standard locations on the local
    filesystem, for common tasks such as user-specific directories or system-wide
    configuration directories.
*/

/*!
    \enum QStandardPaths::StandardLocation

    This enum describes the different locations that can be queried using
    methods such as QStandardPaths::writableLocation, QStandardPaths::standardLocations,
    and QStandardPaths::displayName.

    \value DesktopLocation Returns the user's desktop directory.
    \value DocumentsLocation Returns the user's document.
    \value FontsLocation Returns the user's fonts.
    \value ApplicationsLocation Returns the user's applications.
    \value MusicLocation Returns the user's music.
    \value MoviesLocation Returns the user's movies.
    \value PicturesLocation Returns the user's pictures.
    \value TempLocation Returns the system's temporary directory.
    \value HomeLocation Returns the user's home directory.
    \value DataLocation Returns a directory location where persistent
           application data can be stored. QCoreApplication::organizationName
           and QCoreApplication::applicationName are appended to the directory location
           returned for GenericDataLocation.
    \value CacheLocation Returns a directory location where user-specific
           non-essential (cached) data should be written.
    \value GenericCacheLocation Returns a directory location where user-specific
           non-essential (cached) data, shared across applications, should be written.
    \value GenericDataLocation Returns a directory location where persistent
           data shared across applications can be stored.
    \value RuntimeLocation Returns a directory location where runtime communication
           files should be written. For instance unix local sockets.
    \value ConfigLocation Returns a directory location where user-specific
           configuration files should be written.
    \value DownloadLocation Returns a directory for user's downloaded files.


    \sa writableLocation() standardLocations() displayName() locate() locateAll()
*/

/*!
    \fn QString QStandardPaths::writableLocation(StandardLocation type)

    Returns the directory where files of \a type should be written to, or an empty string
    if the location cannot be determined.

    \note The storage location returned can be a directory that does not exist; i.e., it
    may need to be created by the system or the user.
*/


/*!
   \fn QStringList QStandardPaths::standardLocations(StandardLocation type)

   Returns all the directories where files of \a type belong.

   Much like the PATH variable, it returns the directories in order of priority,
   starting with the user-specific writableLocation() for the \a type.
 */

/*!
    \enum QStandardPaths::LocateOption

    This enum describes the different flags that can be used for
    controlling the behavior of QStandardPaths::locate and
    QStandardPaths::locateAll.

    \value LocateFile return only files
    \value LocateDirectory return only directories
*/

static bool existsAsSpecified(const QString &path, QStandardPaths::LocateOptions options)
{
    if (options & QStandardPaths::LocateDirectory)
        return QDir(path).exists();
    return QFileInfo(path).isFile();
}

/*!
   Tries to find a file or directory called \a fileName in the standard locations
   for \a type.

   The full path to the first file or directory (depending on \a options) found is returned.
   If no such file or directory can be found, an empty string is returned.
 */
QString QStandardPaths::locate(StandardLocation type, const QString &fileName, LocateOptions options)
{
    const QStringList &dirs = standardLocations(type);
    for (QStringList::const_iterator dir = dirs.constBegin(); dir != dirs.constEnd(); ++dir) {
        const QString path = *dir + QLatin1Char('/') + fileName;
        if (existsAsSpecified(path, options))
            return path;
    }
    return QString();
}

/*!
   Tries to find all files or directories called \a fileName in the standard locations
   for \a type.

   The \a options flag allows to specify whether to look for files or directories.

   Returns the list of all the files that were found.
 */
QStringList QStandardPaths::locateAll(StandardLocation type, const QString &fileName, LocateOptions options)
{
    const QStringList &dirs = standardLocations(type);
    QStringList result;
    for (QStringList::const_iterator dir = dirs.constBegin(); dir != dirs.constEnd(); ++dir) {
        const QString path = *dir + QLatin1Char('/') + fileName;
        if (existsAsSpecified(path, options))
            result.append(path);
    }
    return result;
}

#ifdef Q_OS_WIN
static QStringList executableExtensions()
{
    QStringList ret = QString::fromLocal8Bit(qgetenv("PATHEXT")).split(QLatin1Char(';'));
    if (!ret.contains(QLatin1String(".exe"), Qt::CaseInsensitive)) {
        // If %PATHEXT% does not contain .exe, it is either empty, malformed, or distorted in ways that we cannot support, anyway.
        ret.clear();
        ret << QLatin1String(".exe")
            << QLatin1String(".com")
            << QLatin1String(".bat")
            << QLatin1String(".cmd");
    }
    return ret;
}
#endif

static QString checkExecutable(const QString &path)
{
    const QFileInfo info(path);
    if (info.isBundle())
        return info.bundleName();
    if (info.isFile() && info.isExecutable())
        return QDir::cleanPath(path);
    return QString();
}

/*!
  Finds the executable named \a executableName in the paths specified by \a paths,
  or the system paths if \a paths is empty.

  On most operating systems the system path is determined by the PATH environment variable.

  The directories where to search for the executable can be set in the \a paths argument.
  To search in both your own paths and the system paths, call findExecutable twice, once with
  \a paths set and once with \a paths empty.

  Symlinks are not resolved, in order to preserve behavior for the case of executables
  whose behavior depends on the name they are invoked with.

  \note On Windows, the usual executable extensions (from the PATHEXT environment variable)
  are automatically appended, so that for instance findExecutable("foo") will find foo.exe
  or foo.bat if present.

  Returns the absolute file path to the executable, or an empty string if not found.
 */
QString QStandardPaths::findExecutable(const QString &executableName, const QStringList &paths)
{
    if (QFileInfo(executableName).isAbsolute())
        return checkExecutable(executableName);

    QStringList searchPaths = paths;
    if (paths.isEmpty()) {
        QByteArray pEnv = qgetenv("PATH");
#if defined(Q_OS_WIN)
        const QLatin1Char pathSep(';');
#else
        const QLatin1Char pathSep(':');
#endif
        searchPaths = QString::fromLocal8Bit(pEnv.constData()).split(pathSep, QString::SkipEmptyParts);
    }

    QDir currentDir = QDir::current();
    QString absPath;
#ifdef Q_OS_WIN
    static QStringList executable_extensions = executableExtensions();
#endif

    for (QStringList::const_iterator p = searchPaths.constBegin(); p != searchPaths.constEnd(); ++p) {
        const QString candidate = currentDir.absoluteFilePath(*p + QLatin1Char('/') + executableName);
#ifdef Q_OS_WIN
        const QString extension = QLatin1Char('.') + QFileInfo(executableName).suffix();
        if (!executable_extensions.contains(extension, Qt::CaseInsensitive)) {
            foreach (const QString &extension, executable_extensions) {
                absPath = checkExecutable(candidate + extension.toLower());
                if (!absPath.isEmpty())
                    break;
            }
        }
#endif
        absPath = checkExecutable(candidate);
        if (!absPath.isEmpty()) {
            break;
        }
    }
    return absPath;
}

/*!
    \fn QString QStandardPaths::displayName(StandardLocation type)

    Returns a localized display name for the given location \a type or
    an empty QString if no relevant location can be found.
*/

QT_END_NAMESPACE

#endif // QT_NO_STANDARDPATHS