content/renderer/web_ui_mojo.cc

   1 // Copyright 2014 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/web_ui_mojo.h"
   6
   7 #include "content/common/view_messages.h"
   8 #include "content/public/renderer/render_frame.h"
   9 #include "content/public/renderer/render_view.h"
  10 #include "content/renderer/web_ui_mojo_context_state.h"
  11 #include "gin/per_context_data.h"
  12 #include "third_party/WebKit/public/web/WebKit.h"
  13 #include "third_party/WebKit/public/web/WebLocalFrame.h"
  14 #include "third_party/WebKit/public/web/WebView.h"
  15 #include "v8/include/v8.h"
  16
  17 namespace content {
  18
  19 namespace {
  20
  21 const char kWebUIMojoContextStateKey[] = "WebUIMojoContextState";
  22
  23 struct WebUIMojoContextStateData : public base::SupportsUserData::Data {
  24   scoped_ptr<WebUIMojoContextState> state;
  25 };
  26
  27 }  // namespace
  28
  29 WebUIMojo::MainFrameObserver::MainFrameObserver(WebUIMojo* web_ui_mojo)
  30     : RenderFrameObserver(RenderFrame::FromWebFrame(
  31           web_ui_mojo->render_view()->GetWebView()->mainFrame())),
  32       web_ui_mojo_(web_ui_mojo) {
  33 }
  34
  35 WebUIMojo::MainFrameObserver::~MainFrameObserver() {
  36 }
  37
  38 void WebUIMojo::MainFrameObserver::WillReleaseScriptContext(
  39     v8::Handle<v8::Context> context,
  40     int world_id) {
  41   web_ui_mojo_->DestroyContextState(context);
  42 }
  43
  44 void WebUIMojo::MainFrameObserver::DidFinishDocumentLoad() {
  45   web_ui_mojo_->OnDidFinishDocumentLoad();
  46 }
  47
  48 WebUIMojo::WebUIMojo(RenderView* render_view)
  49     : RenderViewObserver(render_view),
  50       RenderViewObserverTracker<WebUIMojo>(render_view),
  51       main_frame_observer_(this),
  52       did_finish_document_load_(false) {
  53   CreateContextState();
  54 }
  55
  56 void WebUIMojo::SetBrowserHandle(mojo::ScopedMessagePipeHandle handle) {
  57   if (did_finish_document_load_)
  58     SetHandleOnContextState(handle.Pass());
  59   else
  60     pending_handle_ = handle.Pass();
  61 }
  62
  63 WebUIMojo::~WebUIMojo() {
  64 }
  65
  66 void WebUIMojo::CreateContextState() {
  67   v8::HandleScope handle_scope(blink::mainThreadIsolate());
  68   blink::WebLocalFrame* frame =
  69       render_view()->GetWebView()->mainFrame()->toWebLocalFrame();
  70   v8::Handle<v8::Context> context = frame->mainWorldScriptContext();
  71   gin::PerContextData* context_data = gin::PerContextData::From(context);
  72   WebUIMojoContextStateData* data = new WebUIMojoContextStateData;
  73   data->state.reset(new WebUIMojoContextState(
  74                         render_view()->GetWebView()->mainFrame(), context));
  75   context_data->SetUserData(kWebUIMojoContextStateKey, data);
  76 }
  77
  78 void WebUIMojo::DestroyContextState(v8::Handle<v8::Context> context) {
  79   gin::PerContextData* context_data = gin::PerContextData::From(context);
  80   if (!context_data)
  81     return;
  82   context_data->RemoveUserData(kWebUIMojoContextStateKey);
  83 }
  84
  85 void WebUIMojo::OnDidFinishDocumentLoad() {
  86   did_finish_document_load_ = true;
  87   if (pending_handle_.is_valid())
  88     SetHandleOnContextState(pending_handle_.Pass());
  89 }
  90
  91 void WebUIMojo::SetHandleOnContextState(mojo::ScopedMessagePipeHandle handle) {
  92   DCHECK(did_finish_document_load_);
  93   v8::HandleScope handle_scope(blink::mainThreadIsolate());
  94   WebUIMojoContextState* state = GetContextState();
  95   if (state)
  96     state->SetHandle(handle.Pass());
  97 }
  98
  99 WebUIMojoContextState* WebUIMojo::GetContextState() {
 100   blink::WebLocalFrame* frame =
 101       render_view()->GetWebView()->mainFrame()->toWebLocalFrame();
 102   v8::HandleScope handle_scope(blink::mainThreadIsolate());
 103   v8::Handle<v8::Context> context = frame->mainWorldScriptContext();
 104   gin::PerContextData* context_data = gin::PerContextData::From(context);
 105   if (!context_data)
 106     return NULL;
 107   WebUIMojoContextStateData* context_state =
 108       static_cast<WebUIMojoContextStateData*>(
 109           context_data->GetUserData(kWebUIMojoContextStateKey));
 110   return context_state ? context_state->state.get() : NULL;
 111 }
 112
 113 void WebUIMojo::DidClearWindowObject(blink::WebLocalFrame* frame,
 114                                      int world_id) {
 115   if (frame != render_view()->GetWebView()->mainFrame())
 116     return;
 117
 118   // NOTE: this function may be called early on twice. From the constructor
 119   // mainWorldScriptContext() may trigger this to be called. If we are created
 120   // before the page is loaded (which is very likely), then on first load this
 121   // is called. In the case of the latter we may have already supplied the
 122   // handle to the context state so that if we destroy now the handle is
 123   // lost. If this is the result of the first load then the contextstate should
 124   // be empty and we don't need to destroy it.
 125   WebUIMojoContextState* state = GetContextState();
 126   if (state && !state->module_added())
 127     return;
 128
 129   v8::HandleScope handle_scope(blink::mainThreadIsolate());
 130   DestroyContextState(frame->mainWorldScriptContext());
 131   CreateContextState();
 132 }
 133
 134 }  // namespace content