Introduce QFileNetworkReply in QNetworkAccessManager

The QFileNetworkReply is a wrapper around QFile that
has therefore similar performance. This avoids
the usage of the unperformant QNetworkAccessFileBackend.

The benchmark qfile_vs_qnetworkaccessmanager shows
that the QFileNetworkReply's performance is better
than 0.9x of QFile compared to QNetworkAccessFileBackend
which had about 0.5x of QFile.

Reviewed-by: Peter Hartmann

4 files changed, 326 insertions, 0 deletions

diff --git a/src/network/access/access.pri b/src/network/access/access.pri
index edc1b63..aa36890 100644
--- a/src/network/access/access.pri
+++ b/src/network/access/access.pri
@@ -7,6 +7,7 @@ HEADERS += access/qftp.h \
            access/qhttpnetworkreply_p.h \
 	   access/qhttpnetworkconnection_p.h \
            access/qhttpnetworkconnectionchannel_p.h \
+           access/qfilenetworkreply_p.h \
            access/qnetworkaccessmanager.h \
            access/qnetworkaccessmanager_p.h \
 	   access/qnetworkaccesscache_p.h \
@@ -38,6 +39,7 @@ SOURCES += access/qftp.cpp \
 	   access/qhttpnetworkreply.cpp \
 	   access/qhttpnetworkconnection.cpp \
            access/qhttpnetworkconnectionchannel.cpp \
+           access/qfilenetworkreply.cpp \
            access/qnetworkaccessmanager.cpp \
 	   access/qnetworkaccesscache.cpp \
            access/qnetworkaccessbackend.cpp \
diff --git a/src/network/access/qfilenetworkreply.cpp b/src/network/access/qfilenetworkreply.cpp
new file mode 100644
index 0000000..c878980
--- /dev/null
+++ b/src/network/access/qfilenetworkreply.cpp
@@ -0,0 +1,205 @@
+/****************************************************************************
+**
+** 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 QtNetwork module 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 "qfilenetworkreply_p.h"
+
+#include "QtCore/qdatetime.h"
+#include <QtCore/QCoreApplication>
+#include <QtCore/QFileInfo>
+
+QT_BEGIN_NAMESPACE
+
+QFileNetworkReplyPrivate::QFileNetworkReplyPrivate()
+    : QNetworkReplyPrivate(), realFileSize(0), finished(false)
+{
+}
+
+QFileNetworkReply::QFileNetworkReply(QObject *parent, const QNetworkRequest &req)
+    : QNetworkReply(*new QFileNetworkReplyPrivate(), parent)
+{
+    setRequest(req);
+    setUrl(req.url());
+    setOperation(QNetworkAccessManager::GetOperation);
+    QMetaObject::invokeMethod(this, "_q_startOperation", Qt::QueuedConnection);
+    QNetworkReply::open(QIODevice::ReadOnly);
+}
+
+QFileNetworkReply::~QFileNetworkReply()
+{
+}
+
+// This code is mostly inspired by QNetworkAccessFileBackend
+// We also use its translation context for error messages
+void QFileNetworkReplyPrivate::_q_startOperation()
+{
+    Q_Q(QFileNetworkReply);
+
+    QUrl url = q->url();
+    if (url.host() == QLatin1String("localhost"))
+        url.setHost(QString());
+
+#if !defined(Q_OS_WIN)
+    // do not allow UNC paths on Unix
+    if (!url.host().isEmpty()) {
+        // we handle only local files
+        QString msg = QCoreApplication::translate("QNetworkAccessFileBackend", "Request for opening non-local file %1").arg(url.toString());
+        q->setError(QNetworkReply::ProtocolInvalidOperationError, msg);
+        emit q->error(QNetworkReply::ProtocolInvalidOperationError);
+        doFinished();
+        return;
+    }
+#endif
+    if (url.path().isEmpty())
+        url.setPath(QLatin1String("/"));
+    q->setUrl(url);
+
+
+    QString fileName = url.toLocalFile();
+    if (fileName.isEmpty()) {
+        fileName = url.toString(QUrl::RemoveAuthority | QUrl::RemoveFragment | QUrl::RemoveQuery);
+    }
+    realFile.setFileName(fileName);
+
+    QFileInfo fi(realFile);
+    if (fi.isDir()) {
+        QString msg = QCoreApplication::translate("QNetworkAccessFileBackend", "Cannot open %1: Path is a directory").arg(url.toString());
+        q->setError(QNetworkReply::ContentOperationNotPermittedError, msg);
+        emit q->error(QNetworkReply::ContentOperationNotPermittedError);
+        doFinished();
+        return;
+    }
+
+    bool opened = realFile.open(QIODevice::ReadOnly | QIODevice::Unbuffered);
+
+    // could we open the file?
+    if (!opened) {
+        QString msg = QCoreApplication::translate("QNetworkAccessFileBackend", "Error opening %1: %2")
+                      .arg(realFile.name(), realFile.errorString());
+
+        if (realFile.exists()) {
+            q->setError(QNetworkReply::ContentAccessDenied, msg);
+            emit q->error(QNetworkReply::ContentAccessDenied);
+        } else {
+            q->setError(QNetworkReply::ContentNotFoundError, msg);
+            emit q->error(QNetworkReply::ContentNotFoundError);
+        }
+        doFinished();
+        return;
+    }
+
+    realFileSize = fi.size();
+    q->setHeader(QNetworkRequest::LastModifiedHeader, fi.lastModified());
+    q->setHeader(QNetworkRequest::ContentLengthHeader, realFileSize);
+
+    emit q->metaDataChanged();
+    emit q->downloadProgress(realFileSize, realFileSize);
+    emit q->readyRead();
+    doFinished();
+}
+
+bool QFileNetworkReplyPrivate::isFinished() const
+{
+    return finished;
+}
+
+void QFileNetworkReplyPrivate::doFinished()
+{
+    Q_Q(QFileNetworkReply);
+    finished = true;
+    emit q->finished();
+}
+
+
+void QFileNetworkReply::close()
+{
+    Q_D(QFileNetworkReply);
+    QNetworkReply::close();
+    d->realFile.close();
+
+    if (!d->finished)
+        d->doFinished();
+}
+
+void QFileNetworkReply::abort()
+{
+    Q_D(QFileNetworkReply);
+    QNetworkReply::close();
+    d->realFile.close();
+
+    if (!d->finished)
+        d->doFinished();
+}
+
+qint64 QFileNetworkReply::bytesAvailable() const
+{
+    Q_D(const QFileNetworkReply);
+    return QNetworkReply::bytesAvailable() + d->realFile.bytesAvailable();
+}
+
+bool QFileNetworkReply::isSequential () const
+{
+    return true;
+}
+
+qint64 QFileNetworkReply::size() const
+{
+    Q_D(const QFileNetworkReply);
+    return d->realFileSize;
+}
+
+/*!
+    \internal
+*/
+qint64 QFileNetworkReply::readData(char *data, qint64 maxlen)
+{
+    Q_D(QFileNetworkReply);
+    qint64 ret = d->realFile.read(data, maxlen);
+    if (ret == 0 && bytesAvailable() == 0)
+        return -1; // everything had been read
+    else
+        return ret;
+}
+
+
+QT_END_NAMESPACE
+
+#include "moc_qfilenetworkreply_p.cpp"
+
diff --git a/src/network/access/qfilenetworkreply_p.h b/src/network/access/qfilenetworkreply_p.h
new file mode 100644
index 0000000..831f50a
--- /dev/null
+++ b/src/network/access/qfilenetworkreply_p.h
@@ -0,0 +1,107 @@
+/****************************************************************************
+**
+** 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 QtNetwork module 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.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QFILENETWORKREPLY_P_H
+#define QFILENETWORKREPLY_P_H
+
+//
+//  W A R N I N G
+//  -------------
+//
+// This file is not part of the Qt API.  It exists for the convenience
+// of the Network Access API.  This header file may change from
+// version to version without notice, or even be removed.
+//
+// We mean it.
+//
+
+#include "qnetworkreply.h"
+#include "qnetworkreply_p.h"
+#include "qnetworkaccessmanager.h"
+#include <QFile>
+
+QT_BEGIN_NAMESPACE
+
+
+class QFileNetworkReplyPrivate;
+class QFileNetworkReply: public QNetworkReply
+{
+    Q_OBJECT
+public:
+    QFileNetworkReply(QObject *parent, const QNetworkRequest &req);
+    ~QFileNetworkReply();
+    virtual void abort();
+
+    // reimplemented from QNetworkReply
+    virtual void close();
+    virtual qint64 bytesAvailable() const;
+    virtual bool isSequential () const;
+    qint64 size() const;
+
+
+    virtual qint64 readData(char *data, qint64 maxlen);
+
+    Q_DECLARE_PRIVATE(QFileNetworkReply)
+    Q_PRIVATE_SLOT(d_func(), void _q_startOperation())
+
+};
+
+class QFileNetworkReplyPrivate: public QNetworkReplyPrivate
+{
+public:
+    QFileNetworkReplyPrivate();
+
+    QFile realFile;
+    qint64 realFileSize;
+
+    void _q_startOperation();
+
+    virtual bool isFinished() const;
+    void doFinished();
+    bool finished;
+
+
+    Q_DECLARE_PUBLIC(QFileNetworkReply)
+};
+
+QT_END_NAMESPACE
+
+#endif // QFILENETWORKREPLY_P_H
diff --git a/src/network/access/qnetworkaccessmanager.cpp b/src/network/access/qnetworkaccessmanager.cpp
index b1160aa..754633d 100644
--- a/src/network/access/qnetworkaccessmanager.cpp
+++ b/src/network/access/qnetworkaccessmanager.cpp
@@ -52,6 +52,7 @@
 #include "qnetworkaccessfilebackend_p.h"
 #include "qnetworkaccessdatabackend_p.h"
 #include "qnetworkaccessdebugpipebackend_p.h"
+#include "qfilenetworkreply_p.h"
 
 #include "QtCore/qbuffer.h"
 #include "QtCore/qurl.h"
@@ -681,6 +682,17 @@ QNetworkReply *QNetworkAccessManager::createRequest(QNetworkAccessManager::Opera
                                                     QIODevice *outgoingData)
 {
     Q_D(QNetworkAccessManager);
+
+    // fast path for GET on file:// URLs
+    // Also if the scheme is empty we consider it a file.
+    // The QNetworkAccessFileBackend will right now only be used
+    // for PUT or qrc://
+    if (op == QNetworkAccessManager::GetOperation
+         && (req.url().scheme() == QLatin1String("file")
+             || req.url().scheme().isEmpty())) {
+        return new QFileNetworkReply(this, req);
+    }
+
     QNetworkRequest request = req;
     if (!request.header(QNetworkRequest::ContentLengthHeader).isValid() &&
         outgoingData && !outgoingData->isSequential()) {