view base/TempDirectory.h @ 490:c3fb8258e34d

* Make it possible to import an entire session from an RDF document.
  However, at the moment the timings of events appear to be constrained
  by how far the audio decoder has got through its audio file at the
  time the event is queried -- need to investigate.

/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */

/*
    Sonic Visualiser
    An audio file viewer and annotation editor.
    Centre for Digital Music, Queen Mary, University of London.
    This file copyright 2006 Chris Cannam.
    
    This program is free software; you can redistribute it and/or
    modify it under the terms of the GNU General Public License as
    published by the Free Software Foundation; either version 2 of the
    License, or (at your option) any later version.  See the file
    COPYING included with this distribution for more information.
*/

#ifndef _TEMP_DIRECTORY_H_
#define _TEMP_DIRECTORY_H_

#include <QString>
#include <QMutex>

#include <exception>

/**
 * A class that manages the creation and removal of a temporary
 * directory tree to store data during the program run.  There is one
 * root temporary directory for the program, created on demand and
 * deleted when the program exits.
 *
 * This class is thread safe.
 */

class TempDirectory
{
public:
    static TempDirectory *getInstance();
    
    virtual ~TempDirectory();

    /**
     * Return the path of the directory in which the temporary
     * directory has been or will be created.  This directory is
     * particular to this application, although not to this instance
     * of it, and it will not be removed when the application exits.
     * Persistent cache data or similar may be placed in this
     * directory or other, non-temporary subdirectories of it.
     *
     * If this directory does not exist, it will be created.  Throw
     * DirectoryCreationFailed if the directory cannot be created.
     */
    QString getContainingPath();

    /**
     * Create the root temporary directory if necessary, and return
     * its path.  This directory will be removed when the application
     * exits.
     *
     * Throw DirectoryCreationFailed if the directory cannot be
     * created.
     */
    QString getPath();

    /** 
     * Create an immediate subdirectory of the root temporary
     * directory of the given name, if it doesn't already exist, and
     * return its path.  This directory will be removed when the
     * application exits.
     * 
     * Throw DirectoryCreationFailed if the directory cannot be
     * created.
     */
    QString getSubDirectoryPath(QString subdir);

    /**
     * Delete the temporary directory (before exiting).
     */
    void cleanup();

protected:
    TempDirectory();

    QString createTempDirectoryIn(QString inDir);
    void cleanupDirectory(QString tmpDir);
    void cleanupAbandonedDirectories(QString svDir);

    QString m_tmpdir;
    QMutex m_mutex;

    static TempDirectory *m_instance;
};


#endif