/****************************************************************************
**
** 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.
**
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** accordance with the Qt Commercial License Agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and Nokia.
**
** 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.
**
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** rights. These rights are described in the Nokia Qt LGPL Exception
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
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** Alternatively, this file may be used under the terms of the GNU
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** packaging of this file. Please review the following information to
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**
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****************************************************************************/
//#define QNETWORKDISKCACHE_DEBUG
#ifndef QT_NO_NETWORKDISKCACHE
#include "networkdiskcache.h"
#include "networkdiskcache_p.h"
#include "QtCore/qscopedpointer.h"
#include <qfile.h>
#include <qdir.h>
#include <qdatetime.h>
#include <qdiriterator.h>
#include <qurl.h>
#include <qdebug.h>
#define MAX_COMPRESSION_SIZE (1024 * 1024 * 3)
#define CACHE_SUBDIR_COUNT 16
QT_BEGIN_NAMESPACE
/*!
\class QNetworkDiskCache
\since 4.5
\inmodule QtNetwork
\brief The QNetworkDiskCache class provides a very basic disk cache.
QNetworkDiskCache stores each url in its own file inside of the
cacheDirectory using QDataStream. Files with a text MimeType
are compressed using qCompress. Each cache file starts with "cache_"
and ends in ".cache". Data is written to disk only in insert()
and updateMetaData().
Currently you can not share the same cache files with more then
one disk cache.
QNetworkDiskCache by default limits the amount of space that the cache will
use on the system to 50MB.
Note you have to set the cache directory before it will work.
A network disk cache can be enabled by:
\snippet doc/src/snippets/code/src_network_access_qnetworkdiskcache.cpp 0
When sending requests, to control the preference of when to use the cache
and when to use the network, consider the following:
\snippet doc/src/snippets/code/src_network_access_qnetworkdiskcache.cpp 1
To check whether the response came from the cache or from the network, the
following can be applied:
\snippet doc/src/snippets/code/src_network_access_qnetworkdiskcache.cpp 2
*/
/*!
Creates a new disk cache. The \a parent argument is passed to
QAbstractNetworkCache's constructor.
*/
NetworkDiskCache::NetworkDiskCache(QObject *parent)
: QAbstractNetworkCache(*new NetworkDiskCachePrivate, parent)
{
}
/*!
Destroys the cache object. This does not clear the disk cache.
*/
NetworkDiskCache::~NetworkDiskCache()
{
Q_D(NetworkDiskCache);
QHashIterator<QIODevice*, QCacheItem*> it(d->inserting);
while (it.hasNext()) {
it.next();
delete it.value();
}
}
/*!
Returns the location where cached files will be stored.
*/
QString NetworkDiskCache::cacheDirectory() const
{
Q_D(const NetworkDiskCache);
return d->cacheDirectory;
}
/*!
Sets the directory where cached files will be stored to \a cacheDir
QNetworkDiskCache will create this directory if it does not exists.
Prepared cache items will be stored in the new cache directory when
they are inserted.
\sa QDesktopServices::CacheLocation
*/
void NetworkDiskCache::setCacheDirectory(const QString &cacheDir)
{
#if defined(QNETWORKDISKCACHE_DEBUG)
qDebug() << "NetworkDiskCache::setCacheDirectory()" << cacheDir;
#endif
Q_D(NetworkDiskCache);
if (cacheDir.isEmpty())
return;
d->cacheDirectory = cacheDir;
QDir cDir(d->cacheDirectory);
d->cacheDirectory = cDir.absolutePath();
if (!d->cacheDirectory.endsWith(QLatin1Char('/')))
d->cacheDirectory += QLatin1Char('/');
QDir dir;
// Setup and create directories
if (!QFile::exists(d->cacheDirectory))
{
// ### make a static QDir function for this...
dir.mkpath(d->cacheDirectory);
}
QString subDirectory;
for (int i = 0; i < CACHE_SUBDIR_COUNT; i++)
{
subDirectory = d->cacheDirectory + QString("%1").arg(i, 0, 16) + QLatin1Char('/');
if (!QFile::exists(subDirectory))
{
dir.mkpath(subDirectory);
}
}
// For Temporary Prepared Directory
dir.mkpath(d->cacheDirectory + QLatin1String("prepared/"));
}
/*!
\reimp
*/
qint64 NetworkDiskCache::cacheSize() const
{
#if defined(QNETWORKDISKCACHE_DEBUG)
qDebug() << "NetworkDiskCache::cacheSize()";
#endif
Q_D(const NetworkDiskCache);
if (d->cacheDirectory.isEmpty())
return 0;
if (d->currentCacheSize < 0) {
NetworkDiskCache *that = const_cast<NetworkDiskCache*>(this);
that->d_func()->currentCacheSize = that->expire();
}
return d->currentCacheSize;
}
/*!
\reimp
*/
QIODevice *NetworkDiskCache::prepare(const QNetworkCacheMetaData &metaData)
{
#if defined(QNETWORKDISKCACHE_DEBUG)
qDebug() << "NetworkDiskCache::prepare()" << metaData.url();
#endif
Q_D(NetworkDiskCache);
if (!metaData.isValid() || !metaData.url().isValid() || !metaData.saveToDisk())
return 0;
if (d->cacheDirectory.isEmpty()) {
qWarning() << "NetworkDiskCache::prepare() The cache directory is not set";
return 0;
}
foreach (QNetworkCacheMetaData::RawHeader header, metaData.rawHeaders()) {
if (header.first.toLower() == "content-length") {
qint64 size = header.second.toInt();
if (size > (maximumCacheSize() * 3)/4)
return 0;
break;
}
}
QScopedPointer<QCacheItem> cacheItem(new QCacheItem);
cacheItem->metaData = metaData;
QIODevice *device = 0;
if (cacheItem->canCompress()) {
cacheItem->data.open(QBuffer::ReadWrite);
device = &(cacheItem->data);
} else {
QString templateName = d->tmpCacheFileName();
QT_TRY {
cacheItem->file = new QTemporaryFile(templateName, &cacheItem->data);
} QT_CATCH(...) {
cacheItem->file = 0;
}
if (!cacheItem->file || !cacheItem->file->open()) {
qWarning() << "NetworkDiskCache::prepare() unable to open temporary file";
cacheItem.reset();
return 0;
}
cacheItem->writeHeader(cacheItem->file);
device = cacheItem->file;
}
d->inserting[device] = cacheItem.take();
return device;
}
/*!
\reimp
*/
void NetworkDiskCache::insert(QIODevice *device)
{
#if defined(QNETWORKDISKCACHE_DEBUG)
qDebug() << "NetworkDiskCache::insert()" << device;
#endif
Q_D(NetworkDiskCache);
QHash<QIODevice*, QCacheItem*>::iterator it = d->inserting.find(device);
if (it == d->inserting.end()) {
qWarning() << "NetworkDiskCache::insert() called on a device we don't know about" << device;
return;
}
d->storeItem(it.value());
delete it.value();
d->inserting.erase(it);
}
// CRC32 implementation.
// Could be made into new API QByteArray:qChecksum32()
static const quint32 crc_tbl32[256] = {
0x00000000, 0x77073096, 0xee0e612c, 0x990951ba,
0x076dc419, 0x706af48f, 0xe963a535, 0x9e6495a3,
0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988,
0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91,
0x1db71064, 0x6ab020f2, 0xf3b97148, 0x84be41de,
0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7,
0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec,
0x14015c4f, 0x63066cd9, 0xfa0f3d63, 0x8d080df5,
0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172,
0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b,
0x35b5a8fa, 0x42b2986c, 0xdbbbc9d6, 0xacbcf940,
0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59,
0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116,
0x21b4f4b5, 0x56b3c423, 0xcfba9599, 0xb8bda50f,
0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924,
0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d,
0x76dc4190, 0x01db7106, 0x98d220bc, 0xefd5102a,
0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433,
0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818,
0x7f6a0dbb, 0x086d3d2d, 0x91646c97, 0xe6635c01,
0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e,
0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457,
0x65b0d9c6, 0x12b7e950, 0x8bbeb8ea, 0xfcb9887c,
0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65,
0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2,
0x4adfa541, 0x3dd895d7, 0xa4d1c46d, 0xd3d6f4fb,
0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0,
0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9,
0x5005713c, 0x270241aa, 0xbe0b1010, 0xc90c2086,
0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f,
0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4,
0x59b33d17, 0x2eb40d81, 0xb7bd5c3b, 0xc0ba6cad,
0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a,
0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683,
0xe3630b12, 0x94643b84, 0x0d6d6a3e, 0x7a6a5aa8,
0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1,
0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe,
0xf762575d, 0x806567cb, 0x196c3671, 0x6e6b06e7,
0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc,
0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5,
0xd6d6a3e8, 0xa1d1937e, 0x38d8c2c4, 0x4fdff252,
0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b,
0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60,
0xdf60efc3, 0xa867df55, 0x316e8eef, 0x4669be79,
0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236,
0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f,
0xc5ba3bbe, 0xb2bd0b28, 0x2bb45a92, 0x5cb36a04,
0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d,
0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a,
0x9c0906a9, 0xeb0e363f, 0x72076785, 0x05005713,
0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38,
0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21,
0x86d3d2d4, 0xf1d4e242, 0x68ddb3f8, 0x1fda836e,
0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777,
0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c,
0x8f659eff, 0xf862ae69, 0x616bffd3, 0x166ccf45,
0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2,
0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db,
0xaed16a4a, 0xd9d65adc, 0x40df0b66, 0x37d83bf0,
0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9,
0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6,
0xbad03605, 0xcdd70693, 0x54de5729, 0x23d967bf,
0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94,
0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d
};
quint32 NetworkDiskCachePrivate::crc32(const char *data, uint len)
{
const uchar *p = reinterpret_cast<const uchar *>(data);
const uchar *q = p + len;
const quint32 init = 0xFFFFFFFFL;
quint32 crc32 = init;
while (p < q) {
crc32 = (crc32 >> 8) ^ crc_tbl32[(crc32 ^ *p++) & 0xffL];
}
return crc32 ^ init ;
}
void NetworkDiskCachePrivate::storeItem(QCacheItem *cacheItem)
{
Q_Q(NetworkDiskCache);
// just an idea of not caching anything more than 15k
//if (cacheItem->size() > (15*1024)) return;
Q_ASSERT(cacheItem->metaData.saveToDisk());
QString fileName = cacheFileName(cacheItem->metaData.url());
Q_ASSERT(!fileName.isEmpty());
if (QFile::exists(fileName)) {
if (!QFile::remove(fileName)) {
qWarning() << "NetworkDiskCache: couldn't remove the cache file " << fileName;
return;
}
}
if (currentCacheSize > 0)
currentCacheSize += 1024 + cacheItem->size();
currentCacheSize = q->expire();
if (!cacheItem->file) {
QString templateName = tmpCacheFileName();
cacheItem->file = new QTemporaryFile(templateName, &cacheItem->data);
if (cacheItem->file->open()) {
cacheItem->writeHeader(cacheItem->file);
cacheItem->writeCompressedData(cacheItem->file);
}
}
if (cacheItem->file
&& cacheItem->file->isOpen()
&& cacheItem->file->error() == QFile::NoError) {
cacheItem->file->setAutoRemove(false);
// ### use atomic rename rather then remove & rename
if (cacheItem->file->rename(fileName))
currentCacheSize += cacheItem->file->size();
else
cacheItem->file->setAutoRemove(true);
}
if (cacheItem->metaData.url() == lastItem.metaData.url())
lastItem.reset();
}
/*!
\reimp
*/
bool NetworkDiskCache::remove(const QUrl &url)
{
#if defined(QNETWORKDISKCACHE_DEBUG)
qDebug() << "NetworkDiskCache::remove()" << url;
#endif
Q_D(NetworkDiskCache);
// remove is also used to cancel insertions, not a common operation
QHashIterator<QIODevice*, QCacheItem*> it(d->inserting);
while (it.hasNext()) {
it.next();
QCacheItem *item = it.value();
if (item && item->metaData.url() == url) {
delete item;
d->inserting.remove(it.key());
return true;
}
}
if (d->lastItem.metaData.url() == url)
d->lastItem.reset();
return d->removeFile(d->cacheFileName(url));
}
/*!
Put all of the misc file removing into one function to be extra safe
*/
bool NetworkDiskCachePrivate::removeFile(const QString &file)
{
#if defined(QNETWORKDISKCACHE_DEBUG)
qDebug() << "NetworkDiskCache::removeFile()" << file;
#endif
if (file.isEmpty())
return false;
QFileInfo info(file);
QString fileName = info.fileName();
qint64 size = info.size();
if (QFile::remove(file)) {
currentCacheSize -= size;
return true;
}
return false;
}
/*!
\reimp
*/
QNetworkCacheMetaData NetworkDiskCache::metaData(const QUrl &url)
{
#if defined(QNETWORKDISKCACHE_DEBUG)
qDebug() << "NetworkDiskCache::metaData()" << url;
#endif
Q_D(NetworkDiskCache);
if (d->lastItem.metaData.url() == url)
return d->lastItem.metaData;
return fileMetaData(d->cacheFileName(url));
}
/*!
Returns the QNetworkCacheMetaData for the cache file \a fileName.
If \a fileName is not a cache file QNetworkCacheMetaData will be invalid.
*/
QNetworkCacheMetaData NetworkDiskCache::fileMetaData(const QString &fileName) const
{
#if defined(QNETWORKDISKCACHE_DEBUG)
qDebug() << "NetworkDiskCache::fileMetaData()" << fileName;
#endif
Q_D(const NetworkDiskCache);
QFile file(fileName);
if (!file.open(QFile::ReadOnly))
return QNetworkCacheMetaData();
if (!d->lastItem.read(&file, false)) {
file.close();
NetworkDiskCachePrivate *that = const_cast<NetworkDiskCachePrivate*>(d);
that->removeFile(fileName);
}
return d->lastItem.metaData;
}
/*!
\reimp
*/
QIODevice *NetworkDiskCache::data(const QUrl &url)
{
#if defined(QNETWORKDISKCACHE_DEBUG)
qDebug() << "NetworkDiskCache::data()" << url;
#endif
Q_D(NetworkDiskCache);
QScopedPointer<QBuffer> buffer;
if (!url.isValid())
return 0;
if (d->lastItem.metaData.url() == url && d->lastItem.data.isOpen()) {
buffer.reset(new QBuffer);
buffer->setData(d->lastItem.data.data());
} else {
QScopedPointer<QFile> file(new QFile(d->cacheFileName(url)));
if (!file->open(QFile::ReadOnly | QIODevice::Unbuffered))
return 0;
if (!d->lastItem.read(file.data(), true)) {
file->close();
remove(url);
return 0;
}
if (d->lastItem.data.isOpen()) {
// compressed
buffer.reset(new QBuffer);
buffer->setData(d->lastItem.data.data());
} else {
buffer.reset(new QBuffer);
// ### verify that QFile uses the fd size and not the file name
qint64 size = file->size() - file->pos();
const uchar *p = 0;
#ifndef Q_OS_WINCE
p = file->map(file->pos(), size);
#endif
if (p) {
buffer->setData((const char *)p, size);
file.take()->setParent(buffer.data());
} else {
buffer->setData(file->readAll());
}
}
}
buffer->open(QBuffer::ReadOnly);
return buffer.take();
}
/*!
\reimp
*/
void NetworkDiskCache::updateMetaData(const QNetworkCacheMetaData &metaData)
{
#if defined(QNETWORKDISKCACHE_DEBUG)
qDebug() << "NetworkDiskCache::updateMetaData()" << metaData.url();
#endif
QUrl url = metaData.url();
QIODevice *oldDevice = data(url);
if (!oldDevice) {
#if defined(QNETWORKDISKCACHE_DEBUG)
qDebug() << "NetworkDiskCache::updateMetaData(), no device!";
#endif
return;
}
QIODevice *newDevice = prepare(metaData);
if (!newDevice) {
#if defined(QNETWORKDISKCACHE_DEBUG)
qDebug() << "NetworkDiskCache::updateMetaData(), no new device!" << url;
#endif
return;
}
char data[1024];
while (!oldDevice->atEnd()) {
qint64 s = oldDevice->read(data, 1024);
newDevice->write(data, s);
}
delete oldDevice;
insert(newDevice);
}
/*!
Returns the current maximum size for the disk cache.
\sa setMaximumCacheSize()
*/
qint64 NetworkDiskCache::maximumCacheSize() const
{
Q_D(const NetworkDiskCache);
return d->maximumCacheSize;
}
/*!
Sets the maximum size of the disk cache to be \a size.
If the new size is smaller then the current cache size then the cache will call expire().
\sa maximumCacheSize()
*/
void NetworkDiskCache::setMaximumCacheSize(qint64 size)
{
Q_D(NetworkDiskCache);
bool expireCache = (size < d->maximumCacheSize);
d->maximumCacheSize = size;
if (expireCache)
d->currentCacheSize = expire();
}
/*!
Cleans the cache so that its size is under the maximum cache size.
Returns the current size of the cache.
When the current size of the cache is greater than the maximumCacheSize()
older cache files are removed until the total size is less then 90% of
maximumCacheSize() starting with the oldest ones first using the file
creation date to determine how old a cache file is.
Subclasses can reimplement this function to change the order that cache
files are removed taking into account information in the application
knows about that QNetworkDiskCache does not, for example the number of times
a cache is accessed.
Note: cacheSize() calls expire if the current cache size is unknown.
\sa maximumCacheSize(), fileMetaData()
*/
qint64 NetworkDiskCache::expire()
{
Q_D(NetworkDiskCache);
if (d->currentCacheSize >= 0 && d->currentCacheSize < maximumCacheSize())
return d->currentCacheSize;
if (cacheDirectory().isEmpty()) {
qWarning() << "NetworkDiskCache::expire() The cache directory is not set";
return 0;
}
QDir::Filters filters = QDir::AllDirs | QDir:: Files | QDir::NoDotAndDotDot;
QDirIterator it(cacheDirectory(), filters, QDirIterator::Subdirectories);
QMultiMap<QDateTime, QString> cacheItems;
qint64 totalSize = 0;
while (it.hasNext()) {
QString path = it.next();
QFileInfo info = it.fileInfo();
QString fileName = info.fileName();
cacheItems.insert(info.created(), path);
totalSize += info.size();
}
int removedFiles = 0;
qint64 goal = (maximumCacheSize() * 9) / 10;
QMultiMap<QDateTime, QString>::const_iterator i = cacheItems.constBegin();
while (i != cacheItems.constEnd()) {
if (totalSize < goal)
break;
QString name = i.value();
QFile file(name);
qint64 size = file.size();
file.remove();
totalSize -= size;
++removedFiles;
++i;
}
#if defined(QNETWORKDISKCACHE_DEBUG)
if (removedFiles > 0) {
qDebug() << "NetworkDiskCache::expire()"
<< "Removed:" << removedFiles
<< "Kept:" << cacheItems.count() - removedFiles;
}
#endif
if (removedFiles > 0)
d->lastItem.reset();
return totalSize;
}
/*!
\reimp
*/
void NetworkDiskCache::clear()
{
#if defined(QNETWORKDISKCACHE_DEBUG)
qDebug() << "NetworkDiskCache::clear()";
#endif
Q_D(NetworkDiskCache);
qint64 size = d->maximumCacheSize;
d->maximumCacheSize = 0;
d->currentCacheSize = expire();
d->maximumCacheSize = size;
}
QByteArray NetworkDiskCachePrivate::generateId(const QUrl &url) const
{
QUrl cleanUrl = url;
cleanUrl.setPassword(QString());
cleanUrl.setFragment(QString());
QByteArray blob = cleanUrl.toEncoded();
QByteArray hash;
hash.setNum(crc32(blob.data(), blob.length()), 16);
return hash;
}
QString NetworkDiskCachePrivate::tmpCacheFileName() const
{
return cacheDirectory + QLatin1String("prepared/") + QLatin1String("XXXXXX");
}
QString NetworkDiskCachePrivate::cacheFileName(const QUrl &url) const
{
if (!url.isValid())
return QString();
// Directories were already created during setup phase.
QString subDirectory;
QByteArray filenameID;
filenameID = generateId(url);
subDirectory = cacheDirectory + QLatin1Char(filenameID.at(0)) + QLatin1Char('/');
return subDirectory + QLatin1String(filenameID);
}
/*!
We compress small text and JavaScript files.
*/
bool QCacheItem::canCompress() const
{
bool sizeOk = false;
bool typeOk = false;
foreach (QNetworkCacheMetaData::RawHeader header, metaData.rawHeaders()) {
if (header.first.toLower() == "content-length") {
qint64 size = header.second.toLongLong();
if (size > MAX_COMPRESSION_SIZE)
return false;
else
sizeOk = true;
}
if (header.first.toLower() == "content-type") {
QByteArray type = header.second;
if (type.startsWith("text/")
|| (type.startsWith("application/")
&& (type.endsWith("javascript") || type.endsWith("ecmascript"))))
typeOk = true;
else
return false;
}
if (sizeOk && typeOk)
return true;
}
return false;
}
enum
{
CacheMagic = 0xe8,
CurrentCacheVersion = 7
};
void QCacheItem::writeHeader(QFile *device) const
{
QDataStream out(device);
out << qint32(CacheMagic);
out << qint32(CurrentCacheVersion);
out << metaData;
bool compressed = canCompress();
out << compressed;
}
void QCacheItem::writeCompressedData(QFile *device) const
{
QDataStream out(device);
out << qCompress(data.data());
}
/*!
Returns false if the file is a cache file,
but is an older version and should be removed otherwise true.
*/
bool QCacheItem::read(QFile *device, bool readData)
{
reset();
QDataStream in(device);
qint32 marker;
qint32 v;
in >> marker;
in >> v;
if (marker != CacheMagic)
return true;
// If the cache magic is correct, but the version is not we should remove it
if (v != CurrentCacheVersion)
return false;
bool compressed;
QByteArray dataBA;
in >> metaData;
in >> compressed;
if (readData && compressed) {
in >> dataBA;
data.setData(qUncompress(dataBA));
data.open(QBuffer::ReadOnly);
}
return metaData.isValid();
}
QT_END_NAMESPACE
#endif // QT_NO_NETWORKDISKCACHE