src/content/renderer/java/java_bridge_dispatcher.cc

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "content/renderer/java/java_bridge_dispatcher.h"
   6
   7 #include "content/child/child_process.h"
   8 #include "content/child/npapi/npobject_util.h"  // For CreateNPVariant()
   9 #include "content/common/java_bridge_messages.h"
  10 #include "content/public/renderer/render_frame.h"
  11 #include "content/public/renderer/render_thread.h"
  12 #include "content/renderer/java/java_bridge_channel.h"
  13 #include "third_party/WebKit/public/web/WebBindings.h"
  14 #include "third_party/WebKit/public/web/WebDocument.h"
  15 #include "third_party/WebKit/public/web/WebFrame.h"
  16 #include "third_party/WebKit/public/web/WebView.h"
  17
  18 namespace content {
  19
  20 JavaBridgeDispatcher::JavaBridgeDispatcher(RenderFrame* render_frame)
  21     : RenderFrameObserver(render_frame) {
  22 }
  23
  24 void JavaBridgeDispatcher::EnsureChannelIsSetUp() {
  25   if (channel_.get()) {
  26     return;
  27   }
  28
  29   IPC::ChannelHandle channel_handle;
  30   Send(new JavaBridgeHostMsg_GetChannelHandle(routing_id(), &channel_handle));
  31
  32   channel_ = JavaBridgeChannel::GetJavaBridgeChannel(
  33       channel_handle, ChildProcess::current()->io_message_loop_proxy());
  34 }
  35
  36 JavaBridgeDispatcher::~JavaBridgeDispatcher() {
  37   for (ObjectMap::const_iterator iter = objects_.begin();
  38       iter != objects_.end(); ++iter) {
  39     blink::WebBindings::releaseObject(NPVARIANT_TO_OBJECT(iter->second));
  40   }
  41 }
  42
  43 bool JavaBridgeDispatcher::OnMessageReceived(const IPC::Message& msg) {
  44   bool handled = true;
  45   IPC_BEGIN_MESSAGE_MAP(JavaBridgeDispatcher, msg)
  46     IPC_MESSAGE_HANDLER(JavaBridgeMsg_AddNamedObject, OnAddNamedObject)
  47     IPC_MESSAGE_HANDLER(JavaBridgeMsg_RemoveNamedObject,
  48                         OnRemoveNamedObject)
  49     IPC_MESSAGE_UNHANDLED(handled = false)
  50   IPC_END_MESSAGE_MAP()
  51   return handled;
  52 }
  53
  54 void JavaBridgeDispatcher::DidClearWindowObject() {
  55   // Note that we have to (re)bind all objects, as they will have been unbound
  56   // when the window object was cleared.
  57   for (ObjectMap::const_iterator iter = objects_.begin();
  58        iter != objects_.end();
  59        ++iter) {
  60     NPObject* object = NPVARIANT_TO_OBJECT(iter->second);
  61     // De-associate from the existing V8 wrapper, so we don't pull any
  62     // of the wrapper's custom properties into the context of the page we
  63     // have navigated to.
  64     blink::WebBindings::dropV8WrapperForObject(object);
  65     // This refs the NPObject. This reference is dropped when either the window
  66     // object is later cleared, or the object is GC'ed. So the object may be
  67     // deleted at any time after OnRemoveNamedObject() is called.
  68     render_frame()->GetWebFrame()->bindToWindowObject(iter->first, object);
  69   }
  70 }
  71
  72 void JavaBridgeDispatcher::OnAddNamedObject(
  73     const base::string16& name,
  74     const NPVariant_Param& variant_param) {
  75   DCHECK_EQ(variant_param.type, NPVARIANT_PARAM_SENDER_OBJECT_ROUTING_ID);
  76
  77   EnsureChannelIsSetUp();
  78   if (!channel_.get()) {
  79     // It's possible for |channel_| to be NULL if the RenderView is going away.
  80     return;
  81   }
  82
  83   // This creates an NPObject, wrapped as an NPVariant. Pass 0 for the for
  84   // containing window, as this is only used by plugins to pump the window
  85   // message queue when a method on a renderer-side object causes a dialog to
  86   // be displayed, and the Java Bridge does not need this functionality. The
  87   // page URL is also not required.
  88   NPVariant variant;
  89   bool created =
  90       CreateNPVariant(variant_param, channel_.get(), &variant, 0, GURL());
  91   DCHECK(created);
  92   DCHECK_EQ(variant.type, NPVariantType_Object);
  93
  94   // The NPObject is created with a ref count of one, which we remove when
  95   // OnRemoveNamedObject() is called for that object.
  96   ObjectMap::iterator iter = objects_.find(name);
  97   if (iter != objects_.end()) {
  98     blink::WebBindings::releaseObject(NPVARIANT_TO_OBJECT(iter->second));
  99   }
 100   objects_[name] = variant;
 101 }
 102
 103 void JavaBridgeDispatcher::OnRemoveNamedObject(const base::string16& name) {
 104   if (!channel_.get()) {
 105     DCHECK(objects_.empty());
 106     return;
 107   }
 108
 109   // Removing an object does not unbind it from JavaScript until the window
 110   // object is next cleared. Note that the browser checks that the named object
 111   // is present.
 112   ObjectMap::iterator iter = objects_.find(name);
 113   DCHECK(iter != objects_.end());
 114   blink::WebBindings::releaseObject(NPVARIANT_TO_OBJECT(iter->second));
 115   objects_.erase(iter);
 116 }
 117
 118 }  // namespace content