util/src/network/access/qnetworkaccessfilebackend.cpp
changeset 7 f7bc934e204c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/util/src/network/access/qnetworkaccessfilebackend.cpp	Wed Mar 31 11:06:36 2010 +0300
@@ -0,0 +1,275 @@
+/****************************************************************************
+**
+** Copyright (C) 2010 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 "qnetworkaccessfilebackend_p.h"
+#include "qfileinfo.h"
+#include "qurlinfo.h"
+#include "qdir.h"
+#include "private/qnoncontiguousbytedevice_p.h"
+
+#include <QtCore/QCoreApplication>
+
+QT_BEGIN_NAMESPACE
+
+QNetworkAccessBackend *
+QNetworkAccessFileBackendFactory::create(QNetworkAccessManager::Operation op,
+                                         const QNetworkRequest &request) const
+{
+    // is it an operation we know of?
+    switch (op) {
+    case QNetworkAccessManager::GetOperation:
+    case QNetworkAccessManager::PutOperation:
+        break;
+
+    default:
+        // no, we can't handle this operation
+        return 0;
+    }
+
+    QUrl url = request.url();
+    if (url.scheme() == QLatin1String("qrc") || !url.toLocalFile().isEmpty())
+        return new QNetworkAccessFileBackend;
+    else if (!url.isEmpty() && url.authority().isEmpty()) {
+        // check if QFile could, in theory, open this URL
+        QFileInfo fi(url.toString(QUrl::RemoveAuthority | QUrl::RemoveFragment | QUrl::RemoveQuery));
+        if (fi.exists() || (op == QNetworkAccessManager::PutOperation && fi.dir().exists()))
+            return new QNetworkAccessFileBackend;
+    }
+
+    return 0;
+}
+
+QNetworkAccessFileBackend::QNetworkAccessFileBackend()
+    : uploadByteDevice(0), totalBytes(0), hasUploadFinished(false)
+{
+}
+
+QNetworkAccessFileBackend::~QNetworkAccessFileBackend()
+{
+}
+
+void QNetworkAccessFileBackend::open()
+{
+    QUrl url = this->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
+        error(QNetworkReply::ProtocolInvalidOperationError,
+              QCoreApplication::translate("QNetworkAccessFileBackend", "Request for opening non-local file %1").arg(url.toString()));
+        finished();
+        return;
+    }
+#endif // !defined(Q_OS_WIN)
+    if (url.path().isEmpty())
+        url.setPath(QLatin1String("/"));
+    setUrl(url);
+
+    QString fileName = url.toLocalFile();
+    if (fileName.isEmpty()) {
+        if (url.scheme() == QLatin1String("qrc"))
+            fileName = QLatin1Char(':') + url.path();
+        else
+            fileName = url.toString(QUrl::RemoveAuthority | QUrl::RemoveFragment | QUrl::RemoveQuery);
+    }
+    file.setFileName(fileName);
+
+    if (operation() == QNetworkAccessManager::GetOperation) {
+        if (!loadFileInfo())
+            return;
+    }
+
+    QIODevice::OpenMode mode;
+    switch (operation()) {
+    case QNetworkAccessManager::GetOperation:
+        mode = QIODevice::ReadOnly;
+        break;
+    case QNetworkAccessManager::PutOperation:
+        mode = QIODevice::WriteOnly | QIODevice::Truncate;
+        uploadByteDevice = createUploadByteDevice();
+        QObject::connect(uploadByteDevice, SIGNAL(readyRead()), this, SLOT(uploadReadyReadSlot()));
+        QMetaObject::invokeMethod(this, "uploadReadyReadSlot", Qt::QueuedConnection);
+        break;
+    default:
+        Q_ASSERT_X(false, "QNetworkAccessFileBackend::open",
+                   "Got a request operation I cannot handle!!");
+        return;
+    }
+
+    mode |= QIODevice::Unbuffered;
+    bool opened = file.open(mode);
+
+    // could we open the file?
+    if (!opened) {
+        QString msg = QCoreApplication::translate("QNetworkAccessFileBackend", "Error opening %1: %2")
+                                                .arg(this->url().toString(), file.errorString());
+
+        // why couldn't we open the file?
+        // if we're opening for reading, either it doesn't exist, or it's access denied
+        // if we're opening for writing, not existing means it's access denied too
+        if (file.exists() || operation() == QNetworkAccessManager::PutOperation)
+            error(QNetworkReply::ContentAccessDenied, msg);
+        else
+            error(QNetworkReply::ContentNotFoundError, msg);
+        finished();
+    }
+}
+
+void QNetworkAccessFileBackend::uploadReadyReadSlot()
+{
+    if (hasUploadFinished)
+        return;
+
+    forever {
+        qint64 haveRead;
+        const char *readPointer = uploadByteDevice->readPointer(-1, haveRead);
+        if (haveRead == -1) {
+            // EOF
+            hasUploadFinished = true;
+            file.flush();
+            file.close();
+            finished();
+            break;
+        } else if (haveRead == 0 || readPointer == 0) {
+            // nothing to read right now, we will be called again later
+            break;
+        } else {
+            qint64 haveWritten;
+            haveWritten = file.write(readPointer, haveRead);
+
+            if (haveWritten < 0) {
+                // write error!
+                QString msg = QCoreApplication::translate("QNetworkAccessFileBackend", "Write error writing to %1: %2")
+                              .arg(url().toString(), file.errorString());
+                error(QNetworkReply::ProtocolFailure, msg);
+
+                finished();
+                return;
+            } else {
+                uploadByteDevice->advanceReadPointer(haveWritten);
+            }
+
+
+            file.flush();
+        }
+    }
+}
+
+void QNetworkAccessFileBackend::closeDownstreamChannel()
+{
+    if (operation() == QNetworkAccessManager::GetOperation) {
+        file.close();
+    }
+}
+
+bool QNetworkAccessFileBackend::waitForDownstreamReadyRead(int)
+{
+    Q_ASSERT(operation() == QNetworkAccessManager::GetOperation);
+    return readMoreFromFile();
+}
+
+void QNetworkAccessFileBackend::downstreamReadyWrite()
+{
+    Q_ASSERT_X(operation() == QNetworkAccessManager::GetOperation, "QNetworkAccessFileBackend",
+               "We're being told to download data but operation isn't GET!");
+
+    readMoreFromFile();
+}
+
+bool QNetworkAccessFileBackend::loadFileInfo()
+{
+    QFileInfo fi(file);
+    setHeader(QNetworkRequest::LastModifiedHeader, fi.lastModified());
+    setHeader(QNetworkRequest::ContentLengthHeader, fi.size());
+
+    // signal we're open
+    metaDataChanged();
+
+    if (fi.isDir()) {
+        error(QNetworkReply::ContentOperationNotPermittedError,
+              QCoreApplication::translate("QNetworkAccessFileBackend", "Cannot open %1: Path is a directory").arg(url().toString()));
+        finished();
+        return false;
+    }
+
+    return true;
+}
+
+bool QNetworkAccessFileBackend::readMoreFromFile()
+{
+    qint64 wantToRead;
+    while ((wantToRead = nextDownstreamBlockSize()) > 0) {
+        // ### FIXME!!
+        // Obtain a pointer from the ringbuffer!
+        // Avoid extra copy
+        QByteArray data;
+        data.reserve(wantToRead);
+        qint64 actuallyRead = file.read(data.data(), wantToRead);
+        if (actuallyRead <= 0) {
+            // EOF or error
+            if (file.error() != QFile::NoError) {
+                QString msg = QCoreApplication::translate("QNetworkAccessFileBackend", "Read error reading from %1: %2")
+                              .arg(url().toString(), file.errorString());
+                error(QNetworkReply::ProtocolFailure, msg);
+
+                finished();
+                return false;
+            }
+
+            finished();
+            return true;
+        }
+
+        data.resize(actuallyRead);
+        totalBytes += actuallyRead;
+
+        QByteDataBuffer list;
+        list.append(data);
+        data.clear(); // important because of implicit sharing!
+        writeDownstreamData(list);
+    }
+    return true;
+}
+
+QT_END_NAMESPACE