Refactor URLRequestCustomJob

Move URLRequestCustomJobShared to separate file
and rename class to URLRequestCustomJobProxy.
This commit is a groundwork for following one.

Change-Id: I122b2101789e91186a3bffa9a07eed43b7340418
Reviewed-by: Allan Sandfeld Jensen <allan.jensen@qt.io>

9 files changed, 423 insertions, 314 deletions

diff --git a/src/core/api/qwebengineurlrequestjob.cpp b/src/core/api/qwebengineurlrequestjob.cpp
index 1db23f6ab..742bdf527 100644
--- a/src/core/api/qwebengineurlrequestjob.cpp
+++ b/src/core/api/qwebengineurlrequestjob.cpp
@@ -39,6 +39,7 @@
 
 #include "qwebengineurlrequestjob.h"
 
+#include "url_request_custom_job_proxy.h"
 #include "url_request_custom_job_delegate.h"
 
 using QtWebEngineCore::URLRequestCustomJobDelegate;
diff --git a/src/core/api/qwebengineurlrequestjob.h b/src/core/api/qwebengineurlrequestjob.h
index afa542d7e..4f23ab401 100644
--- a/src/core/api/qwebengineurlrequestjob.h
+++ b/src/core/api/qwebengineurlrequestjob.h
@@ -48,7 +48,7 @@
 
 namespace QtWebEngineCore {
 class URLRequestCustomJobDelegate;
-class URLRequestCustomJobShared;
+class URLRequestCustomJobProxy;
 } // namespace
 
 QT_BEGIN_NAMESPACE
@@ -79,7 +79,7 @@ public:
 
 private:
     QWebEngineUrlRequestJob(QtWebEngineCore::URLRequestCustomJobDelegate *);
-    friend class QtWebEngineCore::URLRequestCustomJobShared;
+    friend class QtWebEngineCore::URLRequestCustomJobProxy;
 
     QtWebEngineCore::URLRequestCustomJobDelegate* d_ptr;
 };
diff --git a/src/core/core_chromium.pri b/src/core/core_chromium.pri
index f13095bfe..b76469833 100644
--- a/src/core/core_chromium.pri
+++ b/src/core/core_chromium.pri
@@ -96,6 +96,7 @@ SOURCES = \
         url_request_context_getter_qt.cpp \
         url_request_custom_job.cpp \
         url_request_custom_job_delegate.cpp \
+        url_request_custom_job_proxy.cpp \
         url_request_qrc_job_qt.cpp \
         user_script.cpp \
         visited_links_manager_qt.cpp \
@@ -171,6 +172,7 @@ HEADERS = \
         url_request_context_getter_qt.h \
         url_request_custom_job.h \
         url_request_custom_job_delegate.h \
+        url_request_custom_job_proxy.h \
         url_request_qrc_job_qt.h \
         user_script.h \
         visited_links_manager_qt.h \
diff --git a/src/core/url_request_custom_job.cpp b/src/core/url_request_custom_job.cpp
index d093efd0a..724a879e0 100644
--- a/src/core/url_request_custom_job.cpp
+++ b/src/core/url_request_custom_job.cpp
@@ -38,57 +38,50 @@
 ****************************************************************************/
 
 #include "url_request_custom_job.h"
-#include "url_request_custom_job_delegate.h"
-
-#include "api/qwebengineurlrequestjob.h"
-#include "api/qwebengineurlschemehandler.h"
-#include "browser_context_adapter.h"
-#include "type_conversion.h"
-
+#include "url_request_custom_job_proxy.h"
 #include "content/public/browser/browser_thread.h"
-#include "net/base/net_errors.h"
 #include "net/base/io_buffer.h"
 
-#include <QFileInfo>
-#include <QMimeDatabase>
-#include <QMimeType>
-#include <QUrl>
+#include <QIODevice>
 
 using namespace net;
 
 namespace QtWebEngineCore {
 
-URLRequestCustomJob::URLRequestCustomJob(URLRequest *request, NetworkDelegate *networkDelegate,
-                                         const std::string &scheme, QWeakPointer<const BrowserContextAdapter> adapter)
+URLRequestCustomJob::URLRequestCustomJob(URLRequest *request,
+                                         NetworkDelegate *networkDelegate,
+                                         const std::string &scheme,
+                                         QWeakPointer<const BrowserContextAdapter> adapter)
     : URLRequestJob(request, networkDelegate)
     , m_scheme(scheme)
     , m_adapter(adapter)
-    , m_shared(new URLRequestCustomJobShared(this))
+    , m_proxy(new URLRequestCustomJobProxy(this))
 {
 }
 
 URLRequestCustomJob::~URLRequestCustomJob()
 {
-    if (m_shared)
-        m_shared->killJob();
+    if (m_proxy)
+        m_proxy->killJob();
 }
 
-static void startAsync(URLRequestCustomJobShared *shared)
+static void startAsync(URLRequestCustomJobProxy *proxy)
 {
-    shared->startAsync();
+    proxy->startAsync();
 }
 
 void URLRequestCustomJob::Start()
 {
     DCHECK_CURRENTLY_ON(content::BrowserThread::IO);
-    content::BrowserThread::PostTask(content::BrowserThread::UI, FROM_HERE, base::Bind(&startAsync, m_shared));
+    content::BrowserThread::PostTask(content::BrowserThread::UI, FROM_HERE,
+                                     base::Bind(&startAsync, m_proxy));
 }
 
 void URLRequestCustomJob::Kill()
 {
-    if (m_shared)
-        m_shared->killJob();
-    m_shared = 0;
+    if (m_proxy)
+        m_proxy->killJob();
+    m_proxy = 0;
 
     URLRequestJob::Kill();
 }
@@ -96,11 +89,11 @@ void URLRequestCustomJob::Kill()
 bool URLRequestCustomJob::GetMimeType(std::string *mimeType) const
 {
     DCHECK_CURRENTLY_ON(content::BrowserThread::IO);
-    if (!m_shared)
+    if (!m_proxy)
         return false;
-    QMutexLocker lock(&m_shared->m_mutex);
-    if (m_shared->m_mimeType.size() > 0) {
-        *mimeType = m_shared->m_mimeType;
+    QMutexLocker lock(&m_proxy->m_mutex);
+    if (m_proxy->m_mimeType.size() > 0) {
+        *mimeType = m_proxy->m_mimeType;
         return true;
     }
     return false;
@@ -109,11 +102,11 @@ bool URLRequestCustomJob::GetMimeType(std::string *mimeType) const
 bool URLRequestCustomJob::GetCharset(std::string* charset)
 {
     DCHECK_CURRENTLY_ON(content::BrowserThread::IO);
-    if (!m_shared)
+    if (!m_proxy)
         return false;
-    QMutexLocker lock(&m_shared->m_mutex);
-    if (m_shared->m_charset.size() > 0) {
-        *charset = m_shared->m_charset;
+    QMutexLocker lock(&m_proxy->m_mutex);
+    if (m_proxy->m_charset.size() > 0) {
+        *charset = m_proxy->m_charset;
         return true;
     }
     return false;
@@ -122,11 +115,11 @@ bool URLRequestCustomJob::GetCharset(std::string* charset)
 bool URLRequestCustomJob::IsRedirectResponse(GURL* location, int* http_status_code)
 {
     DCHECK_CURRENTLY_ON(content::BrowserThread::IO);
-    if (!m_shared)
+    if (!m_proxy)
         return false;
-    QMutexLocker lock(&m_shared->m_mutex);
-    if (m_shared->m_redirect.is_valid()) {
-        *location = m_shared->m_redirect;
+    QMutexLocker lock(&m_proxy->m_mutex);
+    if (m_proxy->m_redirect.is_valid()) {
+        *location = m_proxy->m_redirect;
         *http_status_code = 303;
         return true;
     }
@@ -136,224 +129,18 @@ bool URLRequestCustomJob::IsRedirectResponse(GURL* location, int* http_status_co
 int URLRequestCustomJob::ReadRawData(IOBuffer *buf, int bufSize)
 {
     DCHECK_CURRENTLY_ON(content::BrowserThread::IO);
-    Q_ASSERT(m_shared);
-    QMutexLocker lock(&m_shared->m_mutex);
-    if (m_shared->m_error)
-        return m_shared->m_error;
-    qint64 rv = m_shared->m_device ? m_shared->m_device->read(buf->data(), bufSize) : -1;
+    Q_ASSERT(m_proxy);
+    QMutexLocker lock(&m_proxy->m_mutex);
+    if (m_proxy->m_error)
+        return m_proxy->m_error;
+    qint64 rv = m_proxy->m_device ? m_proxy->m_device->read(buf->data(), bufSize) : -1;
     if (rv >= 0)
         return static_cast<int>(rv);
     else {
         // QIODevice::read might have called fail on us.
-        if (m_shared->m_error)
-            return m_shared->m_error;
+        if (m_proxy->m_error)
+            return m_proxy->m_error;
         return ERR_FAILED;
     }
 }
-
-
-URLRequestCustomJobShared::URLRequestCustomJobShared(URLRequestCustomJob *job)
-    : m_mutex(QMutex::Recursive)
-    , m_job(job)
-    , m_delegate(0)
-    , m_error(0)
-    , m_started(false)
-    , m_asyncInitialized(false)
-    , m_weakFactory(this)
-{
-}
-
-URLRequestCustomJobShared::~URLRequestCustomJobShared()
-{
-    Q_ASSERT(!m_job);
-    Q_ASSERT(!m_delegate);
-}
-
-void URLRequestCustomJobShared::killJob()
-{
-    DCHECK_CURRENTLY_ON(content::BrowserThread::IO);
-    QMutexLocker lock(&m_mutex);
-    m_job = 0;
-    bool doDelete = false;
-    if (m_delegate) {
-        m_delegate->deleteLater();
-    } else {
-        // Do not delete yet if startAsync has not yet run.
-        doDelete = m_asyncInitialized;
-    }
-    if (m_device && m_device->isOpen())
-        m_device->close();
-    m_device = 0;
-    m_weakFactory.InvalidateWeakPtrs();
-    lock.unlock();
-    if (doDelete)
-        delete this;
-}
-
-void URLRequestCustomJobShared::unsetJobDelegate()
-{
-    DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
-    QMutexLocker lock(&m_mutex);
-    m_delegate = 0;
-    bool doDelete = false;
-    if (m_job)
-        abort();
-    else
-        doDelete = true;
-    lock.unlock();
-    if (doDelete)
-        delete this;
-}
-
-void URLRequestCustomJobShared::setReplyMimeType(const std::string &mimeType)
-{
-    DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
-    QMutexLocker lock(&m_mutex);
-    m_mimeType = mimeType;
-}
-
-void URLRequestCustomJobShared::setReplyCharset(const std::string &charset)
-{
-    DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
-    QMutexLocker lock(&m_mutex);
-    m_charset = charset;
-}
-
-void URLRequestCustomJobShared::setReplyDevice(QIODevice *device)
-{
-    DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
-    QMutexLocker lock(&m_mutex);
-    if (!m_job)
-        return;
-    m_device = device;
-    if (m_device && !m_device->isReadable())
-        m_device->open(QIODevice::ReadOnly);
-
-    qint64 size = m_device ? m_device->size() : -1;
-    if (size > 0)
-        m_job->set_expected_content_size(size);
-    if (m_device && m_device->isReadable())
-        content::BrowserThread::PostTask(content::BrowserThread::IO, FROM_HERE, base::Bind(&URLRequestCustomJobShared::notifyStarted, m_weakFactory.GetWeakPtr()));
-    else
-        fail(ERR_INVALID_URL);
-}
-
-void URLRequestCustomJobShared::redirect(const GURL &url)
-{
-    DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
-
-    QMutexLocker lock(&m_mutex);
-    if (m_device || m_error)
-        return;
-    if (!m_job)
-        return;
-    m_redirect = url;
-    content::BrowserThread::PostTask(content::BrowserThread::IO, FROM_HERE, base::Bind(&URLRequestCustomJobShared::notifyStarted, m_weakFactory.GetWeakPtr()));
-}
-
-void URLRequestCustomJobShared::abort()
-{
-    DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
-    QMutexLocker lock(&m_mutex);
-    if (m_device && m_device->isOpen())
-        m_device->close();
-    m_device = 0;
-    if (!m_job)
-        return;
-    content::BrowserThread::PostTask(content::BrowserThread::IO, FROM_HERE, base::Bind(&URLRequestCustomJobShared::notifyCanceled, m_weakFactory.GetWeakPtr()));
-}
-
-void URLRequestCustomJobShared::notifyCanceled()
-{
-    DCHECK_CURRENTLY_ON(content::BrowserThread::IO);
-    QMutexLocker lock(&m_mutex);
-    if (!m_job)
-        return;
-    if (m_started)
-        m_job->NotifyCanceled();
-    else
-        m_job->NotifyStartError(URLRequestStatus(URLRequestStatus::CANCELED, ERR_ABORTED));
-}
-
-void URLRequestCustomJobShared::notifyStarted()
-{
-    DCHECK_CURRENTLY_ON(content::BrowserThread::IO);
-    QMutexLocker lock(&m_mutex);
-    if (!m_job)
-        return;
-    Q_ASSERT(!m_started);
-    m_started = true;
-    m_job->NotifyHeadersComplete();
-}
-
-void URLRequestCustomJobShared::fail(int error)
-{
-    QMutexLocker lock(&m_mutex);
-    m_error = error;
-    if (content::BrowserThread::CurrentlyOn(content::BrowserThread::IO))
-        return;
-    DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
-    if (!m_job)
-        return;
-    content::BrowserThread::PostTask(content::BrowserThread::IO, FROM_HERE, base::Bind(&URLRequestCustomJobShared::notifyFailure, m_weakFactory.GetWeakPtr()));
-}
-
-void URLRequestCustomJobShared::notifyFailure()
-{
-    DCHECK_CURRENTLY_ON(content::BrowserThread::IO);
-    QMutexLocker lock(&m_mutex);
-    if (!m_job)
-        return;
-    if (m_device)
-        m_device->close();
-    if (!m_started)
-        m_job->NotifyStartError(URLRequestStatus::FromError(m_error));
-    // else we fail on the next read, or the read that might already be in progress
-}
-
-GURL URLRequestCustomJobShared::requestUrl()
-{
-    QMutexLocker lock(&m_mutex);
-    if (!m_job)
-        return GURL();
-    return m_job->request()->url();
-}
-
-std::string URLRequestCustomJobShared::requestMethod()
-{
-    QMutexLocker lock(&m_mutex);
-    if (!m_job)
-        return std::string();
-    return m_job->request()->method();
-}
-
-void URLRequestCustomJobShared::startAsync()
-{
-    DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
-    Q_ASSERT(!m_started);
-    Q_ASSERT(!m_delegate);
-    QMutexLocker lock(&m_mutex);
-    if (!m_job) {
-        lock.unlock();
-        delete this;
-        return;
-    }
-
-    QWebEngineUrlSchemeHandler *schemeHandler = 0;
-    QSharedPointer<const BrowserContextAdapter> browserContext = m_job->m_adapter.toStrongRef();
-    if (browserContext)
-        schemeHandler = browserContext->customUrlSchemeHandlers()[toQByteArray(m_job->m_scheme)];
-    if (schemeHandler) {
-        m_delegate = new URLRequestCustomJobDelegate(this);
-        m_asyncInitialized = true;
-        QWebEngineUrlRequestJob *requestJob = new QWebEngineUrlRequestJob(m_delegate);
-        schemeHandler->requestStarted(requestJob);
-    } else {
-        lock.unlock();
-        abort();
-        delete this;
-        return;
-    }
-}
-
 } // namespace
diff --git a/src/core/url_request_custom_job.h b/src/core/url_request_custom_job.h
index 93edb0b8c..171786c7b 100644
--- a/src/core/url_request_custom_job.h
+++ b/src/core/url_request_custom_job.h
@@ -40,19 +40,15 @@
 #ifndef URL_REQUEST_CUSTOM_JOB_H_
 #define URL_REQUEST_CUSTOM_JOB_H_
 
-#include "net/url_request/url_request.h"
 #include "net/url_request/url_request_job.h"
-
-#include <QtCore/QMutex>
-#include <QtCore/QPointer>
-
-QT_FORWARD_DECLARE_CLASS(QIODevice)
+#include "url/gurl.h"
+#include <QtCore/QWeakPointer>
 
 namespace QtWebEngineCore {
 
 class BrowserContextAdapter;
 class URLRequestCustomJobDelegate;
-class URLRequestCustomJobShared;
+class URLRequestCustomJobProxy;
 
 // A request job that handles reading custom URL schemes
 class URLRequestCustomJob : public net::URLRequestJob {
@@ -71,52 +67,12 @@ protected:
 private:
     std::string m_scheme;
     QWeakPointer<const BrowserContextAdapter> m_adapter;
-    URLRequestCustomJobShared *m_shared;
+    URLRequestCustomJobProxy *m_proxy;
 
-    friend class URLRequestCustomJobShared;
+    friend class URLRequestCustomJobProxy;
 
     DISALLOW_COPY_AND_ASSIGN(URLRequestCustomJob);
 };
-
-// A shared state between URLRequestCustomJob living on the IO thread
-// and URLRequestCustomJobDelegate living on the UI thread.
-class URLRequestCustomJobShared {
-public:
-    URLRequestCustomJobShared(URLRequestCustomJob *job);
-    ~URLRequestCustomJobShared();
-
-    void setReplyMimeType(const std::string &);
-    void setReplyCharset(const std::string &);
-    void setReplyDevice(QIODevice *);
-
-    void redirect(const GURL &url);
-    void fail(int);
-    void abort();
-
-    void killJob();
-    void unsetJobDelegate();
-
-    void startAsync();
-    void notifyStarted();
-    void notifyFailure();
-    void notifyCanceled();
-
-    GURL requestUrl();
-    std::string requestMethod();
-
-    QMutex m_mutex;
-    QPointer<QIODevice> m_device;
-    URLRequestCustomJob *m_job;
-    URLRequestCustomJobDelegate *m_delegate;
-    std::string m_mimeType;
-    std::string m_charset;
-    int m_error;
-    GURL m_redirect;
-    bool m_started;
-    bool m_asyncInitialized;
-    base::WeakPtrFactory<URLRequestCustomJobShared> m_weakFactory;
-};
-
 } // namespace QtWebEngineCore
 
 #endif // URL_REQUEST_CUSTOM_JOB_H_
diff --git a/src/core/url_request_custom_job_delegate.cpp b/src/core/url_request_custom_job_delegate.cpp
index 7e806a4e0..83a6353dc 100644
--- a/src/core/url_request_custom_job_delegate.cpp
+++ b/src/core/url_request_custom_job_delegate.cpp
@@ -37,8 +37,8 @@
 **
 ****************************************************************************/
 
-#include "url_request_custom_job.h"
 #include "url_request_custom_job_delegate.h"
+#include "url_request_custom_job_proxy.h"
 
 #include "type_conversion.h"
 #include "net/base/net_errors.h"
@@ -47,40 +47,40 @@
 
 namespace QtWebEngineCore {
 
-URLRequestCustomJobDelegate::URLRequestCustomJobDelegate(URLRequestCustomJobShared *shared)
-    : m_shared(shared)
+URLRequestCustomJobDelegate::URLRequestCustomJobDelegate(URLRequestCustomJobProxy *proxy)
+    : m_proxy(proxy)
 {
 }
 
 URLRequestCustomJobDelegate::~URLRequestCustomJobDelegate()
 {
-    m_shared->unsetJobDelegate();
+    m_proxy->unsetJobDelegate();
 }
 
 QUrl URLRequestCustomJobDelegate::url() const
 {
-    return toQt(m_shared->requestUrl());
+    return toQt(m_proxy->requestUrl());
 }
 
 QByteArray URLRequestCustomJobDelegate::method() const
 {
-    return QByteArray::fromStdString(m_shared->requestMethod());
+    return QByteArray::fromStdString(m_proxy->requestMethod());
 }
 
 void URLRequestCustomJobDelegate::setReply(const QByteArray &contentType, QIODevice *device)
 {
-    m_shared->setReplyMimeType(contentType.toStdString());
-    m_shared->setReplyDevice(device);
+    m_proxy->setReplyMimeType(contentType.toStdString());
+    m_proxy->setReplyDevice(device);
 }
 
 void URLRequestCustomJobDelegate::abort()
 {
-    m_shared->abort();
+    m_proxy->abort();
 }
 
 void URLRequestCustomJobDelegate::redirect(const QUrl &url)
 {
-    m_shared->redirect(toGurl(url));
+    m_proxy->redirect(toGurl(url));
 }
 
 void URLRequestCustomJobDelegate::fail(Error error)
@@ -106,7 +106,7 @@ void URLRequestCustomJobDelegate::fail(Error error)
         break;
     }
     if (net_error)
-        m_shared->fail(net_error);
+        m_proxy->fail(net_error);
 }
 
 } // namespace
diff --git a/src/core/url_request_custom_job_delegate.h b/src/core/url_request_custom_job_delegate.h
index 7752d979e..732ff8d7a 100644
--- a/src/core/url_request_custom_job_delegate.h
+++ b/src/core/url_request_custom_job_delegate.h
@@ -49,7 +49,7 @@ QT_FORWARD_DECLARE_CLASS(QIODevice)
 
 namespace QtWebEngineCore {
 
-class URLRequestCustomJobShared;
+class URLRequestCustomJobProxy;
 
 class QWEBENGINE_EXPORT URLRequestCustomJobDelegate : public QObject {
     Q_OBJECT
@@ -75,10 +75,10 @@ public:
     void fail(Error);
 
 private:
-    URLRequestCustomJobDelegate(URLRequestCustomJobShared *shared);
+    URLRequestCustomJobDelegate(URLRequestCustomJobProxy *proxy);
 
-    friend class URLRequestCustomJobShared;
-    URLRequestCustomJobShared *m_shared;
+    friend class URLRequestCustomJobProxy;
+    URLRequestCustomJobProxy *m_proxy;
 };
 
 } // namespace
diff --git a/src/core/url_request_custom_job_proxy.cpp b/src/core/url_request_custom_job_proxy.cpp
new file mode 100644
index 000000000..c6233709e
--- /dev/null
+++ b/src/core/url_request_custom_job_proxy.cpp
@@ -0,0 +1,266 @@
+/****************************************************************************
+**
+** Copyright (C) 2017 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtWebEngine module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "url_request_custom_job_proxy.h"
+#include "url_request_custom_job.h"
+#include "url_request_custom_job_delegate.h"
+#include "api/qwebengineurlrequestjob.h"
+#include "browser_context_adapter.h"
+#include "type_conversion.h"
+#include "content/public/browser/browser_thread.h"
+
+using namespace net;
+
+namespace QtWebEngineCore {
+
+URLRequestCustomJobProxy::URLRequestCustomJobProxy(URLRequestCustomJob *job)
+    : m_mutex(QMutex::Recursive)
+    , m_job(job)
+    , m_delegate(0)
+    , m_error(0)
+    , m_started(false)
+    , m_asyncInitialized(false)
+    , m_weakFactory(this)
+{
+}
+
+URLRequestCustomJobProxy::~URLRequestCustomJobProxy()
+{
+    Q_ASSERT(!m_job);
+    Q_ASSERT(!m_delegate);
+}
+
+void URLRequestCustomJobProxy::killJob()
+{
+    DCHECK_CURRENTLY_ON(content::BrowserThread::IO);
+    QMutexLocker lock(&m_mutex);
+    m_job = 0;
+    bool doDelete = false;
+    if (m_delegate) {
+        m_delegate->deleteLater();
+    } else {
+        // Do not delete yet if startAsync has not yet run.
+        doDelete = m_asyncInitialized;
+    }
+    if (m_device && m_device->isOpen())
+        m_device->close();
+    m_device = 0;
+    m_weakFactory.InvalidateWeakPtrs();
+    lock.unlock();
+    if (doDelete)
+        delete this;
+}
+
+void URLRequestCustomJobProxy::unsetJobDelegate()
+{
+    DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
+    QMutexLocker lock(&m_mutex);
+    m_delegate = 0;
+    bool doDelete = false;
+    if (m_job)
+        abort();
+    else
+        doDelete = true;
+    lock.unlock();
+    if (doDelete)
+        delete this;
+}
+
+void URLRequestCustomJobProxy::setReplyMimeType(const std::string &mimeType)
+{
+    DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
+    QMutexLocker lock(&m_mutex);
+    m_mimeType = mimeType;
+}
+
+void URLRequestCustomJobProxy::setReplyCharset(const std::string &charset)
+{
+    DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
+    QMutexLocker lock(&m_mutex);
+    m_charset = charset;
+}
+
+void URLRequestCustomJobProxy::setReplyDevice(QIODevice *device)
+{
+    DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
+    QMutexLocker lock(&m_mutex);
+    if (!m_job)
+        return;
+    m_device = device;
+    if (m_device && !m_device->isReadable())
+        m_device->open(QIODevice::ReadOnly);
+
+    qint64 size = m_device ? m_device->size() : -1;
+    if (size > 0)
+        m_job->set_expected_content_size(size);
+    if (m_device && m_device->isReadable()) {
+        content::BrowserThread::PostTask(
+                    content::BrowserThread::IO, FROM_HERE,
+                    base::Bind(&URLRequestCustomJobProxy::notifyStarted,
+                               m_weakFactory.GetWeakPtr()));
+    } else {
+        fail(ERR_INVALID_URL);
+    }
+}
+
+void URLRequestCustomJobProxy::redirect(const GURL &url)
+{
+    DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
+
+    QMutexLocker lock(&m_mutex);
+    if (m_device || m_error)
+        return;
+    if (!m_job)
+        return;
+    m_redirect = url;
+    content::BrowserThread::PostTask(content::BrowserThread::IO, FROM_HERE,
+                                     base::Bind(&URLRequestCustomJobProxy::notifyStarted,
+                                                m_weakFactory.GetWeakPtr()));
+}
+
+void URLRequestCustomJobProxy::abort()
+{
+    DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
+    QMutexLocker lock(&m_mutex);
+    if (m_device && m_device->isOpen())
+        m_device->close();
+    m_device = 0;
+    if (!m_job)
+        return;
+    content::BrowserThread::PostTask(content::BrowserThread::IO, FROM_HERE,
+                                     base::Bind(&URLRequestCustomJobProxy::notifyCanceled,
+                                                m_weakFactory.GetWeakPtr()));
+}
+
+void URLRequestCustomJobProxy::notifyCanceled()
+{
+    DCHECK_CURRENTLY_ON(content::BrowserThread::IO);
+    QMutexLocker lock(&m_mutex);
+    if (!m_job)
+        return;
+    if (m_started)
+        m_job->NotifyCanceled();
+    else
+        m_job->NotifyStartError(URLRequestStatus(URLRequestStatus::CANCELED, ERR_ABORTED));
+}
+
+void URLRequestCustomJobProxy::notifyStarted()
+{
+    DCHECK_CURRENTLY_ON(content::BrowserThread::IO);
+    QMutexLocker lock(&m_mutex);
+    if (!m_job)
+        return;
+    Q_ASSERT(!m_started);
+    m_started = true;
+    m_job->NotifyHeadersComplete();
+}
+
+void URLRequestCustomJobProxy::fail(int error)
+{
+    QMutexLocker lock(&m_mutex);
+    m_error = error;
+    if (content::BrowserThread::CurrentlyOn(content::BrowserThread::IO))
+        return;
+    DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
+    if (!m_job)
+        return;
+    content::BrowserThread::PostTask(content::BrowserThread::IO, FROM_HERE,
+                                     base::Bind(&URLRequestCustomJobProxy::notifyFailure,
+                                                m_weakFactory.GetWeakPtr()));
+}
+
+void URLRequestCustomJobProxy::notifyFailure()
+{
+    DCHECK_CURRENTLY_ON(content::BrowserThread::IO);
+    QMutexLocker lock(&m_mutex);
+    if (!m_job)
+        return;
+    if (m_device)
+        m_device->close();
+    if (!m_started)
+        m_job->NotifyStartError(URLRequestStatus::FromError(m_error));
+    // else we fail on the next read, or the read that might already be in progress
+}
+
+GURL URLRequestCustomJobProxy::requestUrl()
+{
+    QMutexLocker lock(&m_mutex);
+    if (!m_job)
+        return GURL();
+    return m_job->request()->url();
+}
+
+std::string URLRequestCustomJobProxy::requestMethod()
+{
+    QMutexLocker lock(&m_mutex);
+    if (!m_job)
+        return std::string();
+    return m_job->request()->method();
+}
+
+void URLRequestCustomJobProxy::startAsync()
+{
+    DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
+    Q_ASSERT(!m_started);
+    Q_ASSERT(!m_delegate);
+    QMutexLocker lock(&m_mutex);
+    if (!m_job) {
+        lock.unlock();
+        delete this;
+        return;
+    }
+
+    QWebEngineUrlSchemeHandler *schemeHandler = 0;
+    QSharedPointer<const BrowserContextAdapter> browserContext = m_job->m_adapter.toStrongRef();
+    if (browserContext)
+        schemeHandler = browserContext->customUrlSchemeHandlers()[toQByteArray(m_job->m_scheme)];
+    if (schemeHandler) {
+        m_delegate = new URLRequestCustomJobDelegate(this);
+        m_asyncInitialized = true;
+        QWebEngineUrlRequestJob *requestJob = new QWebEngineUrlRequestJob(m_delegate);
+        schemeHandler->requestStarted(requestJob);
+    } else {
+        lock.unlock();
+        abort();
+        delete this;
+        return;
+    }
+}
+
+} // namespace
diff --git a/src/core/url_request_custom_job_proxy.h b/src/core/url_request_custom_job_proxy.h
new file mode 100644
index 000000000..b8c7b5c67
--- /dev/null
+++ b/src/core/url_request_custom_job_proxy.h
@@ -0,0 +1,97 @@
+/****************************************************************************
+**
+** Copyright (C) 2017 Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtWebEngine module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef URL_REQUEST_CUSTOM_JOB_PROXY_H_
+#define URL_REQUEST_CUSTOM_JOB_PROXY_H_
+
+#include "url/gurl.h"
+#include "base/memory/weak_ptr.h"
+#include <QtCore/QMutex>
+#include <QtCore/QPointer>
+
+
+QT_FORWARD_DECLARE_CLASS(QIODevice)
+
+namespace QtWebEngineCore {
+
+class URLRequestCustomJob;
+class URLRequestCustomJobDelegate;
+
+// Used to comunicate between URLRequestCustomJob living on the IO thread
+// and URLRequestCustomJobDelegate living on the UI thread.
+class URLRequestCustomJobProxy {
+public:
+    URLRequestCustomJobProxy(URLRequestCustomJob *job);
+    ~URLRequestCustomJobProxy();
+
+    void setReplyMimeType(const std::string &);
+    void setReplyCharset(const std::string &);
+    void setReplyDevice(QIODevice *);
+
+    void redirect(const GURL &url);
+    void fail(int);
+    void abort();
+
+    void killJob();
+    void unsetJobDelegate();
+
+    void startAsync();
+    void notifyStarted();
+    void notifyFailure();
+    void notifyCanceled();
+
+    GURL requestUrl();
+    std::string requestMethod();
+
+    QMutex m_mutex;
+    QPointer<QIODevice> m_device;
+    URLRequestCustomJob *m_job;
+    URLRequestCustomJobDelegate *m_delegate;
+    std::string m_mimeType;
+    std::string m_charset;
+    int m_error;
+    GURL m_redirect;
+    bool m_started;
+    bool m_asyncInitialized;
+    base::WeakPtrFactory<URLRequestCustomJobProxy> m_weakFactory;
+};
+
+} // namespace QtWebEngineCore
+
+#endif // URL_REQUEST_CUSTOM_JOB_PROXY_H_