examples/network/download/main.cpp
changeset 0 1918ee327afb
child 4 3b1da2848fc7
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/examples/network/download/main.cpp	Mon Jan 11 14:00:40 2010 +0000
@@ -0,0 +1,176 @@
+/****************************************************************************
+**
+** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the examples of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** 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, Nokia gives you certain additional
+** rights.  These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include <QCoreApplication>
+#include <QFile>
+#include <QFileInfo>
+#include <QList>
+#include <QNetworkAccessManager>
+#include <QNetworkRequest>
+#include <QNetworkReply>
+#include <QStringList>
+#include <QTimer>
+#include <QUrl>
+
+#include <stdio.h>
+
+class DownloadManager: public QObject
+{
+    Q_OBJECT
+    QNetworkAccessManager manager;
+    QList<QNetworkReply *> currentDownloads;
+
+public:
+    DownloadManager();
+    void doDownload(const QUrl &url);
+    QString saveFileName(const QUrl &url);
+    bool saveToDisk(const QString &filename, QIODevice *data);
+
+public slots:
+    void execute();
+    void downloadFinished(QNetworkReply *reply);
+};
+
+DownloadManager::DownloadManager()
+{
+    connect(&manager, SIGNAL(finished(QNetworkReply*)),
+            SLOT(downloadFinished(QNetworkReply*)));
+}
+
+void DownloadManager::doDownload(const QUrl &url)
+{
+    QNetworkRequest request(url);
+    QNetworkReply *reply = manager.get(request);
+
+    currentDownloads.append(reply);
+}
+
+QString DownloadManager::saveFileName(const QUrl &url)
+{
+    QString path = url.path();
+    QString basename = QFileInfo(path).fileName();
+
+    if (basename.isEmpty())
+        basename = "download";
+
+    if (QFile::exists(basename)) {
+        // already exists, don't overwrite
+        int i = 0;
+        basename += '.';
+        while (QFile::exists(basename + QString::number(i)))
+            ++i;
+
+        basename += QString::number(i);
+    }
+
+    return basename;
+}
+
+bool DownloadManager::saveToDisk(const QString &filename, QIODevice *data)
+{
+    QFile file(filename);
+    if (!file.open(QIODevice::WriteOnly)) {
+        fprintf(stderr, "Could not open %s for writing: %s\n",
+                qPrintable(filename),
+                qPrintable(file.errorString()));
+        return false;
+    }
+
+    file.write(data->readAll());
+    file.close();
+
+    return true;
+}
+
+void DownloadManager::execute()
+{
+    QStringList args = QCoreApplication::instance()->arguments();
+    args.takeFirst();           // skip the first argument, which is the program's name
+    if (args.isEmpty()) {
+        printf("Qt Download example - downloads all URLs in parallel\n"
+               "Usage: download url1 [url2... urlN]\n"
+               "\n"
+               "Downloads the URLs passed in the command-line to the local directory\n"
+               "If the target file already exists, a .0, .1, .2, etc. is appended to\n"
+               "differentiate.\n");
+        QCoreApplication::instance()->quit();
+        return;
+    }
+
+    foreach (QString arg, args) {
+        QUrl url = QUrl::fromEncoded(arg.toLocal8Bit());
+        doDownload(url);
+    }
+}
+
+void DownloadManager::downloadFinished(QNetworkReply *reply)
+{
+    QUrl url = reply->url();
+    if (reply->error()) {
+        fprintf(stderr, "Download of %s failed: %s\n",
+                url.toEncoded().constData(),
+                qPrintable(reply->errorString()));
+    } else {
+        QString filename = saveFileName(url);
+        if (saveToDisk(filename, reply))
+            printf("Download of %s succeded (saved to %s)\n",
+                   url.toEncoded().constData(), qPrintable(filename));
+    }
+
+    currentDownloads.removeAll(reply);
+    reply->deleteLater();
+
+    if (currentDownloads.isEmpty())
+        // all downloads finished
+        QCoreApplication::instance()->quit();
+}
+
+int main(int argc, char **argv)
+{
+    QCoreApplication app(argc, argv);
+
+    DownloadManager manager;
+    QTimer::singleShot(0, &manager, SLOT(execute()));
+
+    app.exec();
+}
+
+#include "main.moc"