Add RoutingIDIssuer to ensure the correctness of ID to be routed.

content/browser/renderer_host/render_widget_helper.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 "content/browser/renderer_host/render_widget_helper.h"
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/lazy_instance.h"
 #include "base/posix/eintr_wrapper.h"
 #include "base/threading/thread.h"
 #include "base/threading/thread_restrictions.h"
+#include "content/browser/dom_storage/session_storage_namespace_impl.h"
 #include "content/browser/gpu/gpu_process_host_ui_shim.h"
 #include "content/browser/gpu/gpu_surface_tracker.h"
 #include "content/browser/loader/resource_dispatcher_host_impl.h"
 #include "content/browser/renderer_host/render_process_host_impl.h"
 #include "content/browser/renderer_host/render_view_host_impl.h"
-#include "content/browser/dom_storage/session_storage_namespace_impl.h"
+#include "content/browser/renderer_host/routing_id_issuer.h"
 #include "content/common/view_messages.h"
 
 namespace content {
 namespace {
 
 typedef std::map<int, RenderWidgetHelper*> WidgetHelperMap;
 base::LazyInstance<WidgetHelperMap> g_widget_helpers =
     LAZY_INSTANCE_INITIALIZER;
 
 void AddWidgetHelper(int render_process_id,
                      const scoped_refptr<RenderWidgetHelper>& widget_helper) {
   DCHECK_CURRENTLY_ON(BrowserThread::IO);
   // We don't care if RenderWidgetHelpers overwrite an existing process_id. Just
   // want this to be up to date.
   g_widget_helpers.Get()[render_process_id] = widget_helper.get();
 }
 
 }  // namespace
 
 RenderWidgetHelper::RenderWidgetHelper()
     : render_process_id_(-1),
+      routing_id_issuer_(RoutingIDIssuer::Create()),
       resource_dispatcher_host_(NULL) {
 }
 
 RenderWidgetHelper::~RenderWidgetHelper() {
   DCHECK_CURRENTLY_ON(BrowserThread::IO);
 
   // Delete this RWH from the map if it is found.
   WidgetHelperMap& widget_map = g_widget_helpers.Get();
   WidgetHelperMap::iterator it = widget_map.find(render_process_id_);
   if (it != widget_map.end() && it->second == this)
@@ skipping 10 matching lines @@
   render_process_id_ = render_process_id;
   resource_dispatcher_host_ = resource_dispatcher_host;
 
   BrowserThread::PostTask(
       BrowserThread::IO, FROM_HERE,
       base::Bind(&AddWidgetHelper,
                  render_process_id_, make_scoped_refptr(this)));
 }
 
 int RenderWidgetHelper::GetNextRoutingID() {
-  return next_routing_id_.GetNext() + 1;
+  return routing_id_issuer_->IssueNext();
+}
+
+int RenderWidgetHelper::IsRoutingIDProbablyValid(int routing_id) const {
+  return routing_id_issuer_->IsProbablyValid(routing_id);
 }
 
 // static
 RenderWidgetHelper* RenderWidgetHelper::FromProcessHostID(
     int render_process_host_id) {
   DCHECK_CURRENTLY_ON(BrowserThread::IO);
   WidgetHelperMap::const_iterator ci = g_widget_helpers.Get().find(
       render_process_host_id);
   return (ci == g_widget_helpers.Get().end())? NULL : ci->second;
 }
@@ skipping 175 matching lines @@
        i = allocated_dibs_.begin(); i != allocated_dibs_.end(); ++i) {
     if (IGNORE_EINTR(close(i->second)) < 0)
       PLOG(ERROR) << "close: " << i->first;
   }
 
   allocated_dibs_.clear();
 }
 #endif
 
 }  // namespace content