content/browser/accessibility/accessibility_ui.cc

   1 // Copyright (c) 2013 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/browser/accessibility/accessibility_ui.h"
   6
   7 #include "base/bind.h"
   8 #include "base/bind_helpers.h"
   9 #include "base/json/json_writer.h"
  10 #include "base/strings/string_number_conversions.h"
  11 #include "base/strings/utf_string_conversions.h"
  12 #include "base/values.h"
  13 #include "content/browser/accessibility/accessibility_tree_formatter.h"
  14 #include "content/browser/accessibility/browser_accessibility_manager.h"
  15 #include "content/browser/accessibility/browser_accessibility_state_impl.h"
  16 #include "content/browser/renderer_host/render_widget_host_impl.h"
  17 #include "content/common/view_message_enums.h"
  18 #include "content/port/browser/render_widget_host_view_port.h"
  19 #include "content/public/browser/browser_thread.h"
  20 #include "content/public/browser/favicon_status.h"
  21 #include "content/public/browser/navigation_entry.h"
  22 #include "content/public/browser/render_process_host.h"
  23 #include "content/public/browser/render_view_host.h"
  24 #include "content/public/browser/render_widget_host.h"
  25 #include "content/public/browser/render_widget_host_iterator.h"
  26 #include "content/public/browser/web_contents.h"
  27 #include "content/public/browser/web_ui_data_source.h"
  28 #include "content/public/common/url_constants.h"
  29 #include "grit/content_resources.h"
  30 #include "net/base/escape.h"
  31
  32 static const char kDataFile[] = "targets-data.json";
  33
  34 static const char kProcessIdField[]  = "processId";
  35 static const char kRouteIdField[]  = "routeId";
  36 static const char kUrlField[]  = "url";
  37 static const char kNameField[]  = "name";
  38 static const char kFaviconUrlField[] = "favicon_url";
  39 static const char kPidField[]  = "pid";
  40 static const char kAccessibilityModeField[] = "a11y_mode";
  41
  42 namespace content {
  43
  44 namespace {
  45
  46 base::DictionaryValue* BuildTargetDescriptor(
  47     const GURL& url,
  48     const std::string& name,
  49     const GURL& favicon_url,
  50     int process_id,
  51     int route_id,
  52     AccessibilityMode accessibility_mode,
  53     base::ProcessHandle handle = base::kNullProcessHandle) {
  54   base::DictionaryValue* target_data = new base::DictionaryValue();
  55   target_data->SetInteger(kProcessIdField, process_id);
  56   target_data->SetInteger(kRouteIdField, route_id);
  57   target_data->SetString(kUrlField, url.spec());
  58   target_data->SetString(kNameField, net::EscapeForHTML(name));
  59   target_data->SetInteger(kPidField, base::GetProcId(handle));
  60   target_data->SetString(kFaviconUrlField, favicon_url.spec());
  61   target_data->SetInteger(kAccessibilityModeField,
  62                           accessibility_mode);
  63   return target_data;
  64 }
  65
  66 base::DictionaryValue* BuildTargetDescriptor(RenderViewHost* rvh) {
  67   WebContents* web_contents = WebContents::FromRenderViewHost(rvh);
  68   std::string title;
  69   RenderWidgetHostImpl* rwhi = RenderWidgetHostImpl::From(rvh);
  70   AccessibilityMode accessibility_mode = rwhi->accessibility_mode();
  71
  72   GURL url;
  73   GURL favicon_url;
  74   if (web_contents) {
  75     url = web_contents->GetURL();
  76     title = UTF16ToUTF8(web_contents->GetTitle());
  77     NavigationController& controller = web_contents->GetController();
  78     NavigationEntry* entry = controller.GetActiveEntry();
  79     if (entry != NULL && entry->GetURL().is_valid())
  80       favicon_url = entry->GetFavicon().url;
  81   }
  82
  83   return BuildTargetDescriptor(url,
  84                                title,
  85                                favicon_url,
  86                                rvh->GetProcess()->GetID(),
  87                                rvh->GetRoutingID(),
  88                                accessibility_mode);
  89 }
  90
  91 void SendTargetsData(
  92     const WebUIDataSource::GotDataCallback& callback) {
  93   scoped_ptr<base::ListValue> rvh_list(new base::ListValue());
  94
  95   scoped_ptr<RenderWidgetHostIterator> widgets(
  96       RenderWidgetHost::GetRenderWidgetHosts());
  97   while (RenderWidgetHost* widget = widgets->GetNextHost()) {
  98     // Ignore processes that don't have a connection, such as crashed tabs.
  99     if (!widget->GetProcess()->HasConnection())
 100       continue;
 101     if (!widget->IsRenderView())
 102         continue;
 103
 104     RenderViewHost* rvh = RenderViewHost::From(widget);
 105     rvh_list->Append(BuildTargetDescriptor(rvh));
 106   }
 107
 108   scoped_ptr<base::DictionaryValue> data(new base::DictionaryValue());
 109   data->Set("list", rvh_list.release());
 110   scoped_ptr<base::FundamentalValue> a11y_mode(new base::FundamentalValue(
 111       BrowserAccessibilityStateImpl::GetInstance()->accessibility_mode()));
 112   data->Set("global_a11y_mode", a11y_mode.release());
 113
 114   std::string json_string;
 115   base::JSONWriter::Write(data.get(), &json_string);
 116
 117   callback.Run(base::RefCountedString::TakeString(&json_string));
 118 }
 119
 120 bool HandleRequestCallback(
 121     const std::string& path,
 122     const WebUIDataSource::GotDataCallback& callback) {
 123   if (path != kDataFile)
 124     return false;
 125
 126   SendTargetsData(callback);
 127   return true;
 128 }
 129
 130 }  // namespace
 131
 132 AccessibilityUI::AccessibilityUI(WebUI* web_ui)
 133   : WebUIController(web_ui) {
 134   // Set up the chrome://accessibility source.
 135   WebUIDataSource* html_source =
 136       WebUIDataSource::Create(kChromeUIAccessibilityHost);
 137   html_source->SetUseJsonJSFormatV2();
 138
 139   web_ui->RegisterMessageCallback(
 140       "toggleAccessibility",
 141       base::Bind(&AccessibilityUI::ToggleAccessibility,
 142                base::Unretained(this)));
 143   web_ui->RegisterMessageCallback(
 144       "toggleGlobalAccessibility",
 145       base::Bind(&AccessibilityUI::ToggleGlobalAccessibility,
 146                base::Unretained(this)));
 147   web_ui->RegisterMessageCallback(
 148       "requestAccessibilityTree",
 149       base::Bind(&AccessibilityUI::RequestAccessibilityTree,
 150                  base::Unretained(this)));
 151
 152   // Add required resources.
 153   html_source->SetJsonPath("strings.js");
 154   html_source->AddResourcePath("accessibility.css", IDR_ACCESSIBILITY_CSS);
 155   html_source->AddResourcePath("accessibility.js", IDR_ACCESSIBILITY_JS);
 156   html_source->SetDefaultResource(IDR_ACCESSIBILITY_HTML);
 157   html_source->SetRequestFilter(base::Bind(&HandleRequestCallback));
 158
 159   BrowserContext* browser_context =
 160     web_ui->GetWebContents()->GetBrowserContext();
 161   WebUIDataSource::Add(browser_context, html_source);
 162 }
 163
 164 AccessibilityUI::~AccessibilityUI() {
 165 }
 166
 167 void AccessibilityUI::ToggleAccessibility(const base::ListValue* args) {
 168   std::string process_id_str;
 169   std::string route_id_str;
 170   int process_id;
 171   int route_id;
 172   CHECK(args->GetSize() == 2);
 173   CHECK(args->GetString(0, &process_id_str));
 174   CHECK(args->GetString(1, &route_id_str));
 175   CHECK(base::StringToInt(process_id_str,
 176                           &process_id));
 177   CHECK(base::StringToInt(route_id_str, &route_id));
 178
 179   RenderViewHost* rvh = RenderViewHost::FromID(process_id, route_id);
 180   if (!rvh)
 181     return;
 182   RenderWidgetHostImpl* rwhi = RenderWidgetHostImpl::From(rvh);
 183   if (!rwhi)
 184     return;
 185   AccessibilityMode mode = rwhi->accessibility_mode();
 186   if (mode == AccessibilityModeOff)
 187     rwhi->SetAccessibilityMode(AccessibilityModeComplete);
 188   else
 189     rwhi->SetAccessibilityMode(AccessibilityModeOff);
 190 }
 191
 192 void AccessibilityUI::ToggleGlobalAccessibility(const base::ListValue* args) {
 193   BrowserAccessibilityStateImpl* state =
 194       BrowserAccessibilityStateImpl::GetInstance();
 195   AccessibilityMode mode = state->accessibility_mode();
 196   AccessibilityMode new_mode = (mode == AccessibilityModeOff
 197                                 ? AccessibilityModeComplete
 198                                 : AccessibilityModeOff);
 199   state->SetAccessibilityMode(new_mode);
 200 }
 201
 202 void AccessibilityUI::RequestAccessibilityTree(const base::ListValue* args) {
 203   std::string process_id_str;
 204   std::string route_id_str;
 205   int process_id;
 206   int route_id;
 207   CHECK(args->GetSize() == 2);
 208   CHECK(args->GetString(0, &process_id_str));
 209   CHECK(args->GetString(1, &route_id_str));
 210   CHECK(base::StringToInt(process_id_str, &process_id));
 211   CHECK(base::StringToInt(route_id_str, &route_id));
 212
 213   RenderViewHost* rvh = RenderViewHost::FromID(process_id, route_id);
 214   if (!rvh) {
 215     scoped_ptr<base::DictionaryValue> result(new base::DictionaryValue());
 216     result->SetInteger(kProcessIdField, process_id);
 217     result->SetInteger(kRouteIdField, route_id);
 218     result->Set("error", new base::StringValue("Renderer no longer exists."));
 219     web_ui()->CallJavascriptFunction("accessibility.showTree", *(result.get()));
 220     return;
 221   }
 222
 223   scoped_ptr<base::DictionaryValue> result(BuildTargetDescriptor(rvh));
 224   RenderWidgetHostViewPort* host_view = static_cast<RenderWidgetHostViewPort*>(
 225       WebContents::FromRenderViewHost(rvh)->GetRenderWidgetHostView());
 226   if (!host_view) {
 227     result->Set("error",
 228                 new base::StringValue("Could not get accessibility tree."));
 229     web_ui()->CallJavascriptFunction("accessibility.showTree", *(result.get()));
 230     return;
 231   }
 232   scoped_ptr<AccessibilityTreeFormatter> formatter(
 233       AccessibilityTreeFormatter::Create(rvh));
 234   string16 accessibility_contents_utf16;
 235   BrowserAccessibilityManager* manager =
 236       host_view->GetBrowserAccessibilityManager();
 237   if (!manager) {
 238     result->Set("error",
 239                 new base::StringValue("Could not get accessibility tree."));
 240     web_ui()->CallJavascriptFunction("accessibility.showTree", *(result.get()));
 241     return;
 242   }
 243   std::vector<AccessibilityTreeFormatter::Filter> filters;
 244   filters.push_back(AccessibilityTreeFormatter::Filter(
 245       ASCIIToUTF16("*"),
 246       AccessibilityTreeFormatter::Filter::ALLOW));
 247   formatter->SetFilters(filters);
 248   formatter->FormatAccessibilityTree(&accessibility_contents_utf16);
 249
 250   result->Set("tree",
 251               new base::StringValue(UTF16ToUTF8(accessibility_contents_utf16)));
 252   web_ui()->CallJavascriptFunction("accessibility.showTree", *(result.get()));
 253 }
 254
 255 }  // namespace content