view base/TempWriteFile.cpp @ 1879:652c5360e682

Ensure transforms are populated before instantiateDefaultPluginFor runs - otherwise if we have prior knowledge of a transform id, we can find ourselves trying to instantiate it before the plugin factory has heard of it and e.g. knows which server to use
author Chris Cannam
date Thu, 25 Jun 2020 12:20:06 +0100
parents 48e9f538e6e9
children
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/* -*- 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 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.
*/

#include "TempWriteFile.h"

#include "Exceptions.h"

#include <QTemporaryFile>
#include <QDir>
#include <iostream>

TempWriteFile::TempWriteFile(QString target) :
    m_target(target)
{
    QTemporaryFile temp(m_target + ".");
    temp.setAutoRemove(false);
    temp.open(); // creates the file and opens it atomically
    if (temp.error()) {
        SVCERR << "TempWriteFile: Failed to create temporary file in directory of " << m_target << ": " << temp.errorString() << endl;
        throw FileOperationFailed(temp.fileName(), "creation");
    }
    
    m_temp = temp.fileName();
    temp.close(); // does not remove the file
}

TempWriteFile::~TempWriteFile()
{
    if (m_temp != "") {
        QDir dir(QFileInfo(m_temp).dir());
        dir.remove(m_temp);
    }
}

QString
TempWriteFile::getTemporaryFilename()
{
    return m_temp;
}

void
TempWriteFile::moveToTarget()
{
    if (m_temp == "") return;

    QFile tempFile(m_temp);
    QFile targetFile(m_target);
    
    if (targetFile.exists()) {
        if (!targetFile.remove()) {
            SVCERR << "TempWriteFile: WARNING: Failed to remove existing target file " << m_target << " prior to moving temporary file " << m_temp << " to it" << endl;
        }
    }
    
    if (!tempFile.rename(m_target)) {
        SVCERR << "TempWriteFile: Failed to rename temporary file " << m_temp << " to target " << m_target << endl;
        throw FileOperationFailed(m_temp, "rename");
    }

    m_temp = "";
}