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39
40#ifndef QNETWORKACCESSBACKEND_P_H
41#define QNETWORKACCESSBACKEND_P_H
42
43//
44// W A R N I N G
45// -------------
46//
47// This file is not part of the Qt API. It exists for the convenience
48// of the Network Access API. This header file may change from
49// version to version without notice, or even be removed.
50//
51// We mean it.
52//
53
54#include <QtNetwork/private/qtnetworkglobal_p.h>
55#include "qnetworkreplyimpl_p.h"
56#include "QtCore/qobject.h"
57
58QT_BEGIN_NAMESPACE
59
60class QAuthenticator;
61class QNetworkProxy;
62class QNetworkProxyQuery;
63class QNetworkRequest;
64class QStringList;
65class QUrl;
66class QSslConfiguration;
67
68class QNetworkAccessManagerPrivate;
69class QNetworkReplyImplPrivate;
70class QAbstractNetworkCache;
71class QNetworkCacheMetaData;
72class QNonContiguousByteDevice;
73
74// Should support direct file upload from disk or download to disk.
75//
76// - The HTTP handler will use two QIODevices for communication (pull mechanism)
77// - KIO uses a pull mechanism too (data/dataReq signals)
78class QNetworkAccessBackend : public QObject
79{
80 Q_OBJECT
81public:
82 QNetworkAccessBackend();
83 virtual ~QNetworkAccessBackend();
84
85 // To avoid mistaking with QIODevice names, the functions here
86 // have different names. The Connection has two streams:
87 //
88 // - Upstream:
89 // The upstream uses a QNonContiguousByteDevice provided
90 // by the backend. This device emits the usual readyRead()
91 // signal when the backend has data available for the connection
92 // to write. The different backends can listen on this signal
93 // and then pull upload data from the QNonContiguousByteDevice and
94 // deal with it.
95 //
96 //
97 // - Downstream:
98 // Downstream is the data that is being read from this
99 // connection and is given to the user. Downstream operates in a
100 // semi-"push" mechanism: the Connection object pushes the data
101 // it gets from the network, but it should avoid writing too
102 // much if the data isn't being used fast enough. The value
103 // returned by suggestedDownstreamBlockSize() can be used to
104 // determine how much should be written at a time. The
105 // downstreamBytesConsumed() function will be called when the
106 // downstream buffer is consumed by the user -- the Connection
107 // may choose to re-fill it with more data it has ready or get
108 // more data from the network (for instance, by reading from its
109 // socket).
110
111 virtual void open() = 0;
112 virtual bool start();
113 virtual void closeDownstreamChannel() = 0;
114
115 // slot-like:
116 virtual void downstreamReadyWrite();
117 virtual void setDownstreamLimited(bool b);
118 virtual void copyFinished(QIODevice *);
119 virtual void ignoreSslErrors();
120 virtual void ignoreSslErrors(const QList<QSslError> &errors);
121
122 virtual void fetchSslConfiguration(QSslConfiguration &configuration) const;
123 virtual void setSslConfiguration(const QSslConfiguration &configuration);
124
125 virtual QNetworkCacheMetaData fetchCacheMetaData(const QNetworkCacheMetaData &metaData) const;
126
127 // information about the request
128 QNetworkAccessManager::Operation operation() const;
129 QNetworkRequest request() const;
130#ifndef QT_NO_NETWORKPROXY
131 QList<QNetworkProxy> proxyList() const;
132#endif
133
134 QAbstractNetworkCache *networkCache() const;
135 void setCachingEnabled(bool enable);
136 bool isCachingEnabled() const;
137
138 // information about the reply
139 QUrl url() const;
140 void setUrl(const QUrl &url);
141
142 // "cooked" headers
143 QVariant header(QNetworkRequest::KnownHeaders header) const;
144 void setHeader(QNetworkRequest::KnownHeaders header, const QVariant &value);
145
146 // raw headers:
147 bool hasRawHeader(const QByteArray &headerName) const;
148 QList<QByteArray> rawHeaderList() const;
149 QByteArray rawHeader(const QByteArray &headerName) const;
150 void setRawHeader(const QByteArray &headerName, const QByteArray &value);
151
152 // attributes:
153 QVariant attribute(QNetworkRequest::Attribute code) const;
154 void setAttribute(QNetworkRequest::Attribute code, const QVariant &value);
155
156 bool isSynchronous() { return synchronous; }
157 void setSynchronous(bool sync) { synchronous = sync; }
158
159 // return true if the QNonContiguousByteDevice of the upload
160 // data needs to support reset(). Currently needed for HTTP.
161 // This will possibly enable buffering of the upload data.
162 virtual bool needsResetableUploadData() { return false; }
163
164 // Returns \c true if backend is able to resume downloads.
165 virtual bool canResume() const { return false; }
166 virtual void setResumeOffset(quint64 offset) { Q_UNUSED(offset); }
167
168 virtual bool processRequestSynchronously() { return false; }
169
170protected:
171 // Create the device used for reading the upload data
172 QNonContiguousByteDevice* createUploadByteDevice();
173
174 // these functions control the downstream mechanism
175 // that is, data that has come via the connection and is going out the backend
176 qint64 nextDownstreamBlockSize() const;
177 void writeDownstreamData(QByteDataBuffer &list);
178
179 // not actually appending data, it was already written to the user buffer
180 void writeDownstreamDataDownloadBuffer(qint64, qint64);
181 char* getDownloadBuffer(qint64);
182
183 QSharedPointer<QNonContiguousByteDevice> uploadByteDevice;
184
185public slots:
186 // for task 251801, needs to be a slot to be called asynchronously
187 void writeDownstreamData(QIODevice *data);
188
189protected slots:
190 void finished();
191 void error(QNetworkReply::NetworkError code, const QString &errorString);
192#ifndef QT_NO_NETWORKPROXY
193 void proxyAuthenticationRequired(const QNetworkProxy &proxy, QAuthenticator *auth);
194#endif
195 void authenticationRequired(QAuthenticator *auth);
196 void metaDataChanged();
197 void redirectionRequested(const QUrl &destination);
198 void encrypted();
199 void sslErrors(const QList<QSslError> &errors);
200 void emitReplyUploadProgress(qint64 bytesSent, qint64 bytesTotal);
201
202protected:
203 // FIXME In the long run we should get rid of our QNAM architecture
204 // and scrap this ReplyImpl/Backend distinction.
205 QNetworkAccessManagerPrivate *manager;
206 QNetworkReplyImplPrivate *reply;
207
208private:
209 friend class QNetworkAccessManager;
210 friend class QNetworkAccessManagerPrivate;
211 friend class QNetworkReplyImplPrivate;
212
213 bool synchronous;
214};
215
216class QNetworkAccessBackendFactory
217{
218public:
219 QNetworkAccessBackendFactory();
220 virtual ~QNetworkAccessBackendFactory();
221 virtual QStringList supportedSchemes() const = 0;
222 virtual QNetworkAccessBackend *create(QNetworkAccessManager::Operation op,
223 const QNetworkRequest &request) const = 0;
224};
225
226QT_END_NAMESPACE
227
228#endif
229
230

source code of qtbase/src/network/access/qnetworkaccessbackend_p.h