Instant: Use only one hidden WebContents per profile.

chrome/browser/instant/instant_io_context.cc

 // Copyright 2013 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/instant/instant_io_context.h"
 
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/resource_context.h"
 #include "content/public/browser/resource_request_info.h"
-#include "net/url_request/url_request.h"
-
-using content::BrowserThread;
 
 namespace {
 
-// Retrieves the Instant data from the |context|'s named user-data.
-InstantIOContext* GetDataForResourceContext(
-    content::ResourceContext* context) {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
-  return base::UserDataAdapter<InstantIOContext>::Get(
-      context, InstantIOContext::kInstantIOContextKeyName);
-}
+char kUserDataKey;
 
 }  // namespace
 
-const char InstantIOContext::kInstantIOContextKeyName[] = "instant_io_context";
-
 InstantIOContext::InstantIOContext() {
-  // The InstantIOContext is created on the UI thread but is accessed
-  // on the IO thread.
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-}
-
-InstantIOContext::~InstantIOContext() {
+  // This object is created on the UI thread but accessed on the IO thread.
+  DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
 }
 
 // static
 void InstantIOContext::SetUserDataOnIO(
     content::ResourceContext* resource_context,
-    scoped_refptr<InstantIOContext> instant_io_context) {
+    scoped_refptr<InstantIOContext> io_context) {
+  DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::IO));
   resource_context->SetUserData(
-      InstantIOContext::kInstantIOContextKeyName,
-      new base::UserDataAdapter<InstantIOContext>(instant_io_context));
+      &kUserDataKey,
+      new base::UserDataAdapter<InstantIOContext>(io_context));
 }
 
 // static
 void InstantIOContext::AddInstantProcessOnIO(
-    scoped_refptr<InstantIOContext> instant_io_context, int process_id) {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
-  instant_io_context->process_ids_.insert(process_id);
+    scoped_refptr<InstantIOContext> io_context,
+    int process_id) {
+  DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::IO));
+  io_context->process_ids_.insert(process_id);
 }
 
 // static
 void InstantIOContext::RemoveInstantProcessOnIO(
-    scoped_refptr<InstantIOContext> instant_io_context, int process_id) {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
-  instant_io_context->process_ids_.erase(process_id);
-}
-
-// static
-void InstantIOContext::ClearInstantProcessesOnIO(
-    scoped_refptr<InstantIOContext> instant_io_context) {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
-  instant_io_context->process_ids_.clear();
+    scoped_refptr<InstantIOContext> io_context,
+    int process_id) {
+  DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::IO));
+  io_context->process_ids_.erase(process_id);
 }
 
 // static
 bool InstantIOContext::ShouldServiceRequest(const net::URLRequest* request) {
+  DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::IO));
+
   const content::ResourceRequestInfo* info =
       content::ResourceRequestInfo::ForRequest(request);
   if (!info)
     return false;
 
-  InstantIOContext* instant_io_context =
-      GetDataForResourceContext(info->GetContext());
-  if (!instant_io_context)
+  InstantIOContext* io_context =
+      base::UserDataAdapter<InstantIOContext>::Get(info->GetContext(),
+                                                   &kUserDataKey);
+  if (!io_context)
     return false;
 
   int process_id = -1;
   int render_view_id = -1;
   if (info->GetAssociatedRenderView(&process_id, &render_view_id) &&
-      instant_io_context->IsInstantProcess(process_id))
+      io_context->IsInstantProcess(process_id))
     return true;
+
   return false;
 }
 
+InstantIOContext::~InstantIOContext() {
+  // Destruction could happen on either thread (UI or IO).
+}
+
 bool InstantIOContext::IsInstantProcess(int process_id) const {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
-  return process_ids_.count(process_id) != 0;
+  DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::IO));
+  return process_ids_.find(process_id) != process_ids_.end();
 }