<webview>: First stab at implementing media permission request for guests.

content/renderer/browser_plugin/browser_plugin.cc

Index: content/renderer/browser_plugin/browser_plugin.cc
diff --git a/content/renderer/browser_plugin/browser_plugin.cc b/content/renderer/browser_plugin/browser_plugin.cc
index adde725e61b83c614b638541935b9a737c56661b..6fb2b9ecde01e57e35b7f8cf5cffe544e3775be2 100644
--- a/content/renderer/browser_plugin/browser_plugin.cc
+++ b/content/renderer/browser_plugin/browser_plugin.cc
@@ -42,7 +42,10 @@ using WebKit::WebVector;
 namespace content {
 
 namespace {
+const char kAllowMediaAccessCallbackName[] = "allow";
 const char kCrashEventName[] = "crash";
+const char kDenyMediaAccessCallbackName[] = "deny";
+const char kInstanceIdKey[] = "instance_id";
 const char kIsTopLevel[] = "isTopLevel";
 const char kLoadAbortEventName[] = "loadAbort";
 const char kLoadRedirectEventName[] = "loadRedirect";
@@ -52,9 +55,43 @@ const char kNewURL[] = "newUrl";
 const char kOldURL[] = "oldUrl";
 const char kPartitionAttribute[] = "partition";
 const char kPersistPrefix[] = "persist:";
+const char kPermissionRequestEventName[] = "permissionRequest";
+const char kPermissionTypeMedia[] = "media";
+const char kRequestIdKey[] = "request_id";
 const char kSrcAttribute[] = "src";
 const char kType[] = "type";
 const char kURL[] = "url";
+
+void SetMediaAccessPermission(bool allow, const v8::Arguments& args) {
+  int instance_id = -1;
+  int request_id = -1;
+  v8::Local<v8::Value> instance_id_value =
+      args.Callee()->GetHiddenValue(v8::String::New(kInstanceIdKey));
+  v8::Local<v8::Value> request_id_value =
+      args.Callee()->GetHiddenValue(v8::String::New(kRequestIdKey));
+  if (instance_id_value->IsInt32())
+    instance_id = instance_id_value->ToInt32()->Value();
+  if (request_id_value->IsInt32())
+    request_id = request_id_value->ToInt32()->Value();
+
+  if (instance_id != -1 && request_id != -1) {

[Fady Samuel, 2012/10/11 21:41:00]

I feel like these should be DCHECKs rather than if?

[lazyboy, 2012/10/11 23:05:07]

Done.

+    BrowserPlugin* plugin =
+        BrowserPluginManager::Get()->GetBrowserPlugin(instance_id);
+    if (plugin)
+      plugin->AllowMediaAccess(request_id, allow);
+  }
+}
+
+v8::Handle<v8::Value> OnJsAllowMediaAccess(const v8::Arguments& args) {
+  SetMediaAccessPermission(true /* allow */, args);
+  return v8::Undefined();
+}
+
+v8::Handle<v8::Value> OnJsDenyMediaAccess(const v8::Arguments& args) {
+  SetMediaAccessPermission(false /* allow */, args);
+  return v8::Undefined();
+}
+
 }
 
 BrowserPlugin::BrowserPlugin(
@@ -477,6 +514,75 @@ void BrowserPlugin::SetAcceptTouchEvents(bool accept) {
     container()->setIsAcceptingTouchEvents(accept);
 }
 
+void BrowserPlugin::RequestMediaAccess(int request_id) {
+  if (!HasListeners(kPermissionRequestEventName)) {
+    // TODO(lazyboy): Automatically deny request when there is no listener.
+    return;
+  }
+  EventListeners& listeners = event_listener_map_[kPermissionRequestEventName];
+  EventListeners::iterator it = listeners.begin();
+
+  WebKit::WebElement plugin = container()->element();
+  v8::HandleScope handle_scope;
+  v8::Context::Scope context_scope(
+      plugin.document().frame()->mainWorldScriptContext());
+
+  // Set callbacks.
+  // We also save the |instance_id_| and |request_id| in these callbacks. This
+  // is so that we know where to route the callback to when js calls the
+  // callback.
+  //
+  // Javascript:
+  // browser.addEventListener('permissionRequest', function(e) {
+  //   e.allow();  // Calls OnJsAllowMediaAccess().
+  //   e.deny();  //  Calls OnJsDenyMediaAccess().
+  // });
+
+  // Allow callback.
+  v8::Local<v8::Function> allow_function =
+      v8::FunctionTemplate::New(OnJsAllowMediaAccess)->GetFunction();
+  allow_function->SetHiddenValue(v8::String::New(kInstanceIdKey),
+                                 v8::Int32::New(instance_id_));
+  allow_function->SetHiddenValue(v8::String::New(kRequestIdKey),
+                                 v8::Int32::New(request_id));
+  // Deny callback.
+  v8::Local<v8::Function> deny_function =
+      v8::FunctionTemplate::New(OnJsDenyMediaAccess)->GetFunction();
+  deny_function->SetHiddenValue(v8::String::New(kInstanceIdKey),
+                                v8::Int32::New(instance_id_));
+  deny_function->SetHiddenValue(v8::String::New(kRequestIdKey),
+                                v8::Int32::New(request_id));
+
+  // Event object.
+  v8::Local<v8::Value> event =
+      v8::Local<v8::Object>::New(v8::Object::New());
+  // TODO(lazyboy): Also set permission details. Permission details would
+  // include: whether the request was for audio(microphone)/video(webcam)/both.
+  v8::Local<v8::Object>::Cast(event)->Set(
+      v8::String::New(kType), v8::String::New(kPermissionTypeMedia));
+  v8::Local<v8::Object>::Cast(event)->Set(
+      v8::String::New(kAllowMediaAccessCallbackName), allow_function);
+  v8::Local<v8::Object>::Cast(event)->Set(
+      v8::String::New(kDenyMediaAccessCallbackName), deny_function);
+
+  for (; it != listeners.end(); ++it) {
+    // Fire the event listener.
+    container()->element().document().frame()->
+        callFunctionEvenIfScriptDisabled(*it,
+                                         v8::Object::New(),
+                                         1,
+                                         &event);
+  }
+}
+
+void BrowserPlugin::AllowMediaAccess(int request_id, bool allow) {
+  BrowserPluginManager::Get()->Send(
+      new BrowserPluginHostMsg_AllowMediaAccess(render_view_->GetRoutingID(),
+                                                instance_id_,
+                                                request_id,
+                                                allow));
+}
+
 bool BrowserPlugin::HasListeners(const std::string& event_name) {
   return event_listener_map_.find(event_name) != event_listener_map_.end();
 }