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_thread.h"
  11 #include "content/public/renderer/render_view.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(RenderView* render_view)
  21     : RenderViewObserver(render_view) {
  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     WebKit::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(WebKit::WebFrame* web_frame) {
  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(); ++iter) {
  59     // This refs the NPObject. This reference is dropped when either the window
  60     // object is later cleared, or the object is GC'ed. So the object may be
  61     // deleted at any time after OnRemoveNamedObject() is called.
  62     web_frame->bindToWindowObject(iter->first,
  63         NPVARIANT_TO_OBJECT(iter->second));
  64   }
  65 }
  66
  67 void JavaBridgeDispatcher::OnAddNamedObject(
  68     const string16& name,
  69     const NPVariant_Param& variant_param) {
  70   DCHECK_EQ(variant_param.type, NPVARIANT_PARAM_SENDER_OBJECT_ROUTING_ID);
  71
  72   EnsureChannelIsSetUp();
  73   if (!channel_.get()) {
  74     // It's possible for |channel_| to be NULL if the RenderView is going away.
  75     return;
  76   }
  77
  78   // This creates an NPObject, wrapped as an NPVariant. Pass 0 for the for
  79   // containing window, as this is only used by plugins to pump the window
  80   // message queue when a method on a renderer-side object causes a dialog to
  81   // be displayed, and the Java Bridge does not need this functionality. The
  82   // page URL is also not required.
  83   NPVariant variant;
  84   bool created =
  85       CreateNPVariant(variant_param, channel_.get(), &variant, 0, GURL());
  86   DCHECK(created);
  87   DCHECK_EQ(variant.type, NPVariantType_Object);
  88
  89   // The NPObject is created with a ref count of one, which we remove when
  90   // OnRemoveNamedObject() is called for that object.
  91   ObjectMap::iterator iter = objects_.find(name);
  92   if (iter != objects_.end()) {
  93     WebKit::WebBindings::releaseObject(NPVARIANT_TO_OBJECT(iter->second));
  94   }
  95   objects_[name] = variant;
  96 }
  97
  98 void JavaBridgeDispatcher::OnRemoveNamedObject(const string16& name) {
  99   if (!channel_.get()) {
 100     DCHECK(objects_.empty());
 101     return;
 102   }
 103
 104   // Removing an object does not unbind it from JavaScript until the window
 105   // object is next cleared. Note that the browser checks that the named object
 106   // is present.
 107   ObjectMap::iterator iter = objects_.find(name);
 108   DCHECK(iter != objects_.end());
 109   WebKit::WebBindings::releaseObject(NPVARIANT_TO_OBJECT(iter->second));
 110   objects_.erase(iter);
 111 }
 112
 113 }  // namespace content