Add Start/Stop event signalling on Prerenders.

chrome/renderer/prerender/prerender_dispatcher.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/renderer/prerender/prerender_dispatcher.h"
 
 #include <stack>
 
 #include "base/logging.h"
 #include "chrome/common/prerender_messages.h"
@@ skipping 17 matching lines @@
 
 PrerenderDispatcher::~PrerenderDispatcher() {
   WebPrerenderingSupport::shutdown();
 }
 
 bool PrerenderDispatcher::IsPrerenderURL(const GURL& url) const {
   return running_prerender_urls_.count(url) >= 1;
 }
 
 void PrerenderDispatcher::OnPrerenderStart(int prerender_id) {
-  std::map<int, GURL>::iterator it = prerenders_.find(prerender_id);
+  std::map<int, WebPrerender>::iterator it = prerenders_.find(prerender_id);
   if (it == prerenders_.end())
     return;
-  const GURL& url = it->second;
+
+  WebPrerender& prerender = it->second;
+
+  // The prerender should only be null in unit tests.
+  if (prerender.isNull())
+    return;
+
+  prerender.didStartPrerender();
   running_prerender_urls_.insert(
-      std::multimap<GURL, int>::value_type(url, prerender_id));
+      std::multimap<GURL, int>::value_type(prerender.url(), prerender_id));
 }
 
 void PrerenderDispatcher::OnPrerenderAddAlias(int prerender_id,
                                               const GURL& url) {
   DCHECK_LT(0u, prerenders_.count(prerender_id));
   running_prerender_urls_.insert(
       std::multimap<GURL, int>::value_type(url, prerender_id));
 }
 
 void PrerenderDispatcher::OnPrerenderStop(int prerender_id) {
   // It's possible we will receive a spurious remove, so we don't crash in that
   // situation.
-  if (prerenders_.count(prerender_id) == 0)
+  std::map<int, WebPrerender>::iterator it = prerenders_.find(prerender_id);
+  if (it == prerenders_.end())
     return;
+  WebPrerender& prerender = it->second;
+
+  // The prerender should only be null in unit tests.
+  if (!prerender.isNull())
+    prerender.didStopPrerender();
 
   // TODO(cbentzel): We'd also want to send the map of active prerenders when
   // creating a new render process, so the Add/Remove go relative to that.
   // This may not be that big of a deal in practice, since the newly created tab
   // is unlikely to go to the prerendered page.
-  prerenders_.erase(prerender_id);
+  prerenders_.erase(it);
 
   std::stack<std::multimap<GURL, int>::iterator> to_delete;
   for (std::multimap<GURL, int>::iterator it = running_prerender_urls_.begin();
        it != running_prerender_urls_.end(); ++it) {
     if (it->second == prerender_id)
       to_delete.push(it);
   }
   while (!to_delete.empty()) {
     running_prerender_urls_.erase(to_delete.top());
     to_delete.pop();
   }
 }
 
 bool PrerenderDispatcher::OnControlMessageReceived(
     const IPC::Message& message) {
   bool handled = true;
   IPC_BEGIN_MESSAGE_MAP(PrerenderDispatcher, message)
     IPC_MESSAGE_HANDLER(PrerenderMsg_OnPrerenderStart, OnPrerenderStart)
     IPC_MESSAGE_HANDLER(PrerenderMsg_OnPrerenderAddAlias, OnPrerenderAddAlias)
     IPC_MESSAGE_HANDLER(PrerenderMsg_OnPrerenderStop, OnPrerenderStop)
     IPC_MESSAGE_UNHANDLED(handled = false)
   IPC_END_MESSAGE_MAP()
 
   return handled;
 }
 
-void PrerenderDispatcher::add(const WebKit::WebPrerender& prerender) {
+void PrerenderDispatcher::add(const WebPrerender& prerender) {
   const PrerenderExtraData& extra_data =
       PrerenderExtraData::FromPrerender(prerender);
-  prerenders_.insert(std::map<int, GURL>::value_type(extra_data.prerender_id(),
-                                                     prerender.url()));
+  prerenders_.insert(
+      std::map<int, WebPrerender>::value_type(extra_data.prerender_id(),
+                                              prerender));

[mmenke, 2012/12/07 17:11:48]

It looks like we currently eternally accumulate prerenders here if they aren't
started in the browser, even if webkit cancels/abandons them.  Am I missing
something?

[gavinp, 2012/12/14 21:48:52]

No, nothing. But the new uploads should clean that up some.

 
   content::RenderThread::Get()->Send(new PrerenderHostMsg_AddLinkRelPrerender(
       extra_data.prerender_id(), GURL(prerender.url()),
-      content::Referrer(GURL(prerender.referrer()), prerender.referrerPolicy()),
+      content::Referrer(GURL(prerender.referrer()),
+                        prerender.referrerPolicy()),
       extra_data.size(), extra_data.render_view_route_id()));
 }
 
-void PrerenderDispatcher::cancel(const WebKit::WebPrerender& prerender) {
+void PrerenderDispatcher::cancel(const WebPrerender& prerender) {
   const PrerenderExtraData& extra_data =
       PrerenderExtraData::FromPrerender(prerender);
   content::RenderThread::Get()->Send(
       new PrerenderHostMsg_CancelLinkRelPrerender(extra_data.prerender_id()));
 }
 
-void PrerenderDispatcher::abandon(const WebKit::WebPrerender& prerender) {
+void PrerenderDispatcher::abandon(const WebPrerender& prerender) {
   const PrerenderExtraData& extra_data =
       PrerenderExtraData::FromPrerender(prerender);
   content::RenderThread::Get()->Send(
       new PrerenderHostMsg_AbandonLinkRelPrerender(extra_data.prerender_id()));
 }
 
 }  // namespace prerender