6 files changed, 87 insertions, 6 deletions
diff --git a/src/network/access/qhttpnetworkconnectionchannel.cpp b/src/network/access/qhttpnetworkconnectionchannel.cpp
index 4b8fe8aca7..53436b1769 100644
--- a/src/network/access/qhttpnetworkconnectionchannel.cpp
+++ b/src/network/access/qhttpnetworkconnectionchannel.cpp
@@ -205,6 +205,16 @@ bool QHttpNetworkConnectionChannel::sendRequest()
             // _q_connected or _q_encrypted
             return false;
         }
+        QString scheme = request.url().scheme();
+        if (scheme == QLatin1String("preconnect-http")
+            || scheme == QLatin1String("preconnect-https")) {
+            state = QHttpNetworkConnectionChannel::IdleState;
+            reply->d_func()->state = QHttpNetworkReplyPrivate::AllDoneState;
+            allDone();
+            reply = 0; // so we can reuse this channel
+            return true; // we have a working connection and are done
+        }
+
         written = 0; // excluding the header
         bytesTotal = 0;
 
diff --git a/src/network/access/qhttpnetworkreply.cpp b/src/network/access/qhttpnetworkreply.cpp
index eb8a8869cc..1b9e1f5a53 100644
--- a/src/network/access/qhttpnetworkreply.cpp
+++ b/src/network/access/qhttpnetworkreply.cpp
@@ -290,6 +290,11 @@ QHttpNetworkReplyPrivate::QHttpNetworkReplyPrivate(const QUrl &newUrl)
 #endif
 
 {
+    QString scheme = newUrl.scheme();
+    if (scheme == QLatin1String("preconnect-http")
+            || scheme == QLatin1String("preconnect-https"))
+        // make sure we do not close the socket after preconnecting
+        connectionCloseEnabled = false;
 }
 
 QHttpNetworkReplyPrivate::~QHttpNetworkReplyPrivate()
diff --git a/src/network/access/qhttpthreaddelegate.cpp b/src/network/access/qhttpthreaddelegate.cpp
index a2cee48b22..ee3911c72c 100644
--- a/src/network/access/qhttpthreaddelegate.cpp
+++ b/src/network/access/qhttpthreaddelegate.cpp
@@ -107,8 +107,14 @@ static QByteArray makeCacheKey(QUrl &url, QNetworkProxy *proxy)
 {
     QString result;
     QUrl copy = url;
-    bool isEncrypted = copy.scheme().toLower() == QLatin1String("https");
+    QString scheme = copy.scheme().toLower();
+    bool isEncrypted = scheme == QLatin1String("https");
     copy.setPort(copy.port(isEncrypted ? 443 : 80));
+    if (scheme == QLatin1String("preconnect-http")) {
+        copy.setScheme(QLatin1String("http"));
+    } else if (scheme == QLatin1String("preconnect-https")) {
+        copy.setScheme(QLatin1String("https"));
+    }
     result = copy.toString(QUrl::RemoveUserInfo | QUrl::RemovePath |
                            QUrl::RemoveQuery | QUrl::RemoveFragment | QUrl::FullyEncoded);
 
diff --git a/src/network/access/qnetworkaccessmanager.cpp b/src/network/access/qnetworkaccessmanager.cpp
index 13fd167f80..91655ef485 100644
--- a/src/network/access/qnetworkaccessmanager.cpp
+++ b/src/network/access/qnetworkaccessmanager.cpp
@@ -96,9 +96,11 @@ bool getProxyAuth(const QString& proxyHostname, const QString &scheme, QString&
     SecProtocolType protocolType = kSecProtocolTypeAny;
     if (scheme.compare(QLatin1String("ftp"),Qt::CaseInsensitive)==0) {
         protocolType = kSecProtocolTypeFTP;
-    } else if (scheme.compare(QLatin1String("http"),Qt::CaseInsensitive)==0) {
+    } else if (scheme.compare(QLatin1String("http"),Qt::CaseInsensitive)==0
+               || scheme.compare(QLatin1String("preconnect-http"),Qt::CaseInsensitive)==0) {
         protocolType = kSecProtocolTypeHTTP;
-    } else if (scheme.compare(QLatin1String("https"),Qt::CaseInsensitive)==0) {
+    } else if (scheme.compare(QLatin1String("https"),Qt::CaseInsensitive)==0
+               || scheme.compare(QLatin1String("preconnect-https"),Qt::CaseInsensitive)==0) {
         protocolType = kSecProtocolTypeHTTPS;
     }
     QByteArray proxyHostnameUtf8(proxyHostname.toUtf8());
@@ -968,6 +970,53 @@ QNetworkAccessManager::NetworkAccessibility QNetworkAccessManager::networkAccess
     }
 }
 
+#ifndef QT_NO_SSL
+/*!
+    \since 5.2
+
+    Initiates a connection to the host given by \a hostName at port \a port, using
+    \a sslConfiguration. This function is useful to complete the TCP and SSL handshake
+    to a host before the HTTPS request is made, resulting in a lower network latency.
+
+    \note This function has no possibility to report errors.
+
+    \sa connectToHost(), get(), post(), put(), deleteResource()
+*/
+void QNetworkAccessManager::connectToHostEncrypted(const QString &hostName, quint16 port,
+                                                   const QSslConfiguration &sslConfiguration)
+{
+    QUrl url;
+    url.setHost(hostName);
+    url.setPort(port);
+    url.setScheme(QLatin1String("preconnect-https"));
+    QNetworkRequest request(url);
+    if (sslConfiguration != QSslConfiguration::defaultConfiguration())
+        request.setSslConfiguration(sslConfiguration);
+    get(request);
+}
+#endif
+
+/*!
+    \since 5.2
+
+    Initiates a connection to the host given by \a hostName at port \a port.
+    This function is useful to complete the TCP handshake
+    to a host before the HTTP request is made, resulting in a lower network latency.
+
+    \note This function has no possibility to report errors.
+
+    \sa connectToHostEncrypted(), get(), post(), put(), deleteResource()
+*/
+void QNetworkAccessManager::connectToHost(const QString &hostName, quint16 port)
+{
+    QUrl url;
+    url.setHost(hostName);
+    url.setPort(port);
+    url.setScheme(QLatin1String("preconnect-http"));
+    QNetworkRequest request(url);
+    get(request);
+}
+
 /*!
     \internal
 
@@ -1112,9 +1161,9 @@ QNetworkReply *QNetworkAccessManager::createRequest(QNetworkAccessManager::Opera
 
 #ifndef QT_NO_HTTP
     // Since Qt 5 we use the new QNetworkReplyHttpImpl
-    if (scheme == QLatin1String("http")
+    if (scheme == QLatin1String("http") || scheme == QLatin1String("preconnect-http")
 #ifndef QT_NO_SSL
-        || scheme == QLatin1String("https")
+        || scheme == QLatin1String("https") || scheme == QLatin1String("preconnect-https")
 #endif
         ) {
         QNetworkReplyHttpImpl *reply = new QNetworkReplyHttpImpl(this, request, op, outgoingData);
diff --git a/src/network/access/qnetworkaccessmanager.h b/src/network/access/qnetworkaccessmanager.h
index 46e46c49ab..67b9bbcb07 100644
--- a/src/network/access/qnetworkaccessmanager.h
+++ b/src/network/access/qnetworkaccessmanager.h
@@ -43,6 +43,9 @@
 #define QNETWORKACCESSMANAGER_H
 
 #include <QtCore/QObject>
+#ifndef QT_NO_SSL
+#include <QtNetwork/QSslConfiguration>
+#endif
 
 QT_BEGIN_NAMESPACE
 
@@ -135,6 +138,12 @@ public:
     NetworkAccessibility networkAccessible() const;
 #endif
 
+#ifndef QT_NO_SSL
+    void connectToHostEncrypted(const QString &hostName, quint16 port = 443,
+                                const QSslConfiguration &sslConfiguration = QSslConfiguration::defaultConfiguration());
+#endif
+    void connectToHost(const QString &hostName, quint16 port = 80);
+
 Q_SIGNALS:
 #ifndef QT_NO_NETWORKPROXY
     void proxyAuthenticationRequired(const QNetworkProxy &proxy, QAuthenticator *authenticator);
diff --git a/src/network/access/qnetworkreplyhttpimpl.cpp b/src/network/access/qnetworkreplyhttpimpl.cpp
index c04421e5c7..443339f029 100644
--- a/src/network/access/qnetworkreplyhttpimpl.cpp
+++ b/src/network/access/qnetworkreplyhttpimpl.cpp
@@ -629,7 +629,9 @@ void QNetworkReplyHttpImplPrivate::postRequest()
     QUrl url = request.url();
     httpRequest.setUrl(url);
 
-    bool ssl = url.scheme().toLower() == QLatin1String("https");
+    QString scheme = url.scheme().toLower();
+    bool ssl = (scheme == QLatin1String("https")
+                || scheme == QLatin1String("preconnect-https"));
     q->setAttribute(QNetworkRequest::ConnectionEncryptedAttribute, ssl);
     httpRequest.setSsl(ssl);