New link rel=prerender api, using WebKit::WebPrerenderingPlatform

chrome/browser/prerender/prerender_message_filter.cc

+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "chrome/browser/prerender/prerender_message_filter.h"
+
+#include "base/bind.h"
+#include "chrome/browser/browser_process.h"
+#include "chrome/browser/prerender/prerender_link_manager.h"
+#include "chrome/browser/prerender/prerender_link_manager_factory.h"
+#include "chrome/browser/profiles/profile_manager.h"
+#include "chrome/common/prerender_messages.h"
+#include "content/public/browser/browser_thread.h"
+
+using content::BrowserThread;
+
+namespace {
+
+void OnChannelClosingInUIThread(Profile* profile, int render_process_id) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  if (!g_browser_process->profile_manager()->IsValidProfile(profile))
+    return;
+  prerender::PrerenderLinkManager* prerender_link_manager =
+      prerender::PrerenderLinkManagerFactory::GetForProfile(profile);
+  if (!prerender_link_manager)
+    return;
+  prerender_link_manager->OnChannelClosing(render_process_id);
+}
+
+}  // end namespace
+
+namespace prerender {
+
+PrerenderMessageFilter::PrerenderMessageFilter(int render_process_id,
+                                               Profile* profile)
+    : render_process_id_(render_process_id),
+      profile_(profile) {
+}
+
+bool PrerenderMessageFilter::OnMessageReceived(const IPC::Message& message,
+                                               bool* message_was_ok) {
+  bool handled = true;
+  IPC_BEGIN_MESSAGE_MAP_EX(PrerenderMessageFilter, message, *message_was_ok)
+    IPC_MESSAGE_HANDLER(PrerenderHostMsg_AddPrerender, OnAddPrerender)
+    IPC_MESSAGE_HANDLER(PrerenderHostMsg_CancelPrerender, OnCancelPrerender)
+    IPC_MESSAGE_HANDLER(PrerenderHostMsg_AbandonPrerender, OnAbandonPrerender)
+    IPC_MESSAGE_UNHANDLED(handled = false)
+  IPC_END_MESSAGE_MAP()
+
+  return handled;
+}
+
+void PrerenderMessageFilter::OverrideThreadForMessage(
+    const IPC::Message& message, content::BrowserThread::ID* thread) {
+  if (message.type() == PrerenderHostMsg_AddPrerender::ID ||
+      message.type() == PrerenderHostMsg_CancelPrerender::ID ||
+      message.type() == PrerenderHostMsg_AbandonPrerender::ID) {
+    *thread = BrowserThread::UI;
+  }
+}
+
+PrerenderMessageFilter::~PrerenderMessageFilter() {
+}
+
+void PrerenderMessageFilter::OnAddPrerender(
+    int prerender_id,
+    const GURL& url,
+    const content::Referrer& referrer,
+    const gfx::Size& size,
+    int render_view_route_id) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  PrerenderLinkManager* prerender_link_manager =
+      PrerenderLinkManagerFactory::GetForProfile(profile_);
+  if (!prerender_link_manager)
+    return;
+  prerender_link_manager->OnAddPrerender(
+      render_process_id_, prerender_id,
+      url, referrer, size, render_view_route_id);
+}
+
+void PrerenderMessageFilter::OnCancelPrerender(
+    int prerender_id) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  PrerenderLinkManager* prerender_link_manager =
+      PrerenderLinkManagerFactory::GetForProfile(profile_);
+  if (!prerender_link_manager)

[mmenke, 2012/04/30 18:35:22]

Can this happen?

[gavinp, 2012/04/30 23:55:39]

We return NULL if there's no prerender_manager in
PrerenderLinkManagerFactory::BuildServiceInstanceFor.  And, there won't be a
PrerenderManagerFactory on a profile if
PrerenderManager::IsPrerenderingPossible() returns false.  So I think this
happens if you're configured to not use prerendering.  What if, while a
prerender is running, you turn the option off?

[mmenke, 2012/05/01 16:23:21]

Right.  I'd forgotten that we use NULL when disabled.

+    return;
+  prerender_link_manager->OnCancelPrerender(
+      prerender_id, render_process_id_);
+}
+
+void PrerenderMessageFilter::OnAbandonPrerender(
+    int prerender_id) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  PrerenderLinkManager* prerender_link_manager =
+      PrerenderLinkManagerFactory::GetForProfile(profile_);
+  if (!prerender_link_manager)
+    return;
+  prerender_link_manager->OnAbandonPrerender(
+      prerender_id, render_process_id_);
+}
+
+void PrerenderMessageFilter::OnChannelClosing() {
+    BrowserThread::PostTask(
+        BrowserThread::UI, FROM_HERE,
+        base::Bind(&OnChannelClosingInUIThread, profile_, render_process_id_));
+}
+
+}  // namespace prerender
+