Forward accessibility events to the automation extension process.

chrome/browser/extensions/api/automation_internal/automation_event_router.cc

+// Copyright 2015 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/extensions/api/automation_internal/automation_event_router.h"
+
+#include <algorithm>
+#include <string>
+#include <utility>
+
+#include "base/stl_util.h"
+#include "base/values.h"
+#include "chrome/browser/accessibility/ax_tree_id_registry.h"
+#include "chrome/common/extensions/api/automation_internal.h"
+#include "chrome/common/extensions/chrome_extension_messages.h"
+#include "content/public/browser/notification_service.h"
+#include "content/public/browser/notification_source.h"
+#include "content/public/browser/notification_types.h"
+#include "content/public/browser/render_process_host.h"
+#include "extensions/browser/event_router.h"
+#include "ui/accessibility/ax_enums.h"
+#include "ui/accessibility/ax_node_data.h"
+
+namespace extensions {
+
+// static
+AutomationEventRouter* AutomationEventRouter::GetInstance() {
+  return Singleton<AutomationEventRouter,
+                   LeakySingletonTraits<AutomationEventRouter>>::get();
+}
+
+AutomationEventRouter::AutomationEventRouter() {
+  registrar_.Add(this, content::NOTIFICATION_RENDERER_PROCESS_TERMINATED,
+                 content::NotificationService::AllBrowserContextsAndSources());
+  registrar_.Add(this, content::NOTIFICATION_RENDERER_PROCESS_CLOSED,
+                 content::NotificationService::AllBrowserContextsAndSources());
+}
+
+AutomationEventRouter::~AutomationEventRouter() {
+}
+
+void AutomationEventRouter::AddListener(
+    int listener_process_id,
+    int listener_routing_id,
+    int ax_tree_id,
+    bool desktop) {
+  auto iter = std::find_if(
+      listeners_.begin(),
+      listeners_.end(),
+      [=](AutomationListener& item) {

[dcheng, 2015/06/06 00:00:52]

We don't currently permit default captures: http://chromium-cpp.appspot.com/
(search for default captures)

[dmazzoni, 2015/06/08 18:02:57]

Thanks. Still getting used to C++11 style rules.

+        return (item.process_id == listener_process_id &&
+                item.routing_id == listener_routing_id);
+      });
+
+  // Add a new entry if we don't have one with that process and routing id.
+  if (iter == listeners_.end()) {
+    AutomationListener listener;
+    listener.routing_id = listener_routing_id;
+    listener.process_id = listener_process_id;
+    listener.desktop = desktop;
+    listener.tree_ids.insert(ax_tree_id);
+    listeners_.push_back(listener);
+    return;
+  }
+
+  // We have an entry with that process and routing id, so update the set of
+  // tree ids it wants to listen to, and update its desktop permission.
+  iter->tree_ids.insert(ax_tree_id);
+  if (desktop)
+    iter->desktop = true;
+}
+
+void AutomationEventRouter::DispatchAccessibilityEventToAutomation(
+    const ExtensionMsg_AccessibilityEventParams& params) {
+  for (auto iter : listeners_) {

[dcheng, 2015/06/06 00:00:52]

Doesn't this make a copy of AutomationListener on each iteration? Consider using
const auto&

[dmazzoni, 2015/06/08 18:02:57]

Done.

+    if (!iter.desktop &&
+        iter.tree_ids.find(params.tree_id) == iter.tree_ids.end()) {
+      continue;
+    }
+
+    content::RenderProcessHost* rph =
+        content::RenderProcessHost::FromID(iter.process_id);
+    rph->Send(new ExtensionMsg_AccessibilityEvent(iter.routing_id, params));
+  }
+}
+
+void AutomationEventRouter::DispatchTreeDestroyedEventToAutomation(
+    int tree_id,
+    content::BrowserContext* browser_context) {
+  std::string event_name(
+      api::automation_internal::OnAccessibilityTreeDestroyed::kEventName);
+  scoped_ptr<base::ListValue> args(
+      api::automation_internal::OnAccessibilityTreeDestroyed::Create(tree_id));
+  scoped_ptr<Event> event(new Event(event_name, args.Pass()));
+  event->restrict_to_browser_context = browser_context;
+  EventRouter::Get(browser_context)->BroadcastEvent(event.Pass());
+}
+
+AutomationEventRouter::AutomationListener::AutomationListener() {
+}
+
+AutomationEventRouter::AutomationListener::~AutomationListener() {
+}
+
+void AutomationEventRouter::Observe(
+    int type,
+    const content::NotificationSource& source,
+    const content::NotificationDetails& details) {
+  if (type != content::NOTIFICATION_RENDERER_PROCESS_TERMINATED &&
+      type != content::NOTIFICATION_RENDERER_PROCESS_CLOSED) {
+    NOTREACHED();
+    return;
+  }
+
+  content::RenderProcessHost* rph =
+      content::Source<content::RenderProcessHost>(source).ptr();
+  int process_id = rph->GetID();
+  std::remove_if(
+      listeners_.begin(),
+      listeners_.end(),
+      [=](AutomationListener& item) {
+        return item.process_id = process_id;
+      });
+}
+
+}  // namespace extensions