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/browser/renderer_host/render_widget_host_view_base.h"
  18 #include "content/browser/web_contents/web_contents_impl.h"
  19 #include "content/common/view_message_enums.h"
  20 #include "content/grit/content_resources.h"
  21 #include "content/public/browser/favicon_status.h"
  22 #include "content/public/browser/navigation_entry.h"
  23 #include "content/public/browser/render_process_host.h"
  24 #include "content/public/browser/render_view_host.h"
  25 #include "content/public/browser/render_widget_host.h"
  26 #include "content/public/browser/render_widget_host_iterator.h"
  27 #include "content/public/browser/web_contents.h"
  28 #include "content/public/browser/web_ui_data_source.h"
  29 #include "content/public/common/url_constants.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   WebContentsImpl* web_contents = static_cast<WebContentsImpl*>(
  68       WebContents::FromRenderViewHost(rvh));
  69   AccessibilityMode accessibility_mode = AccessibilityModeOff;
  70
  71   std::string title;
  72   GURL url;
  73   GURL favicon_url;
  74   if (web_contents) {
  75     // TODO(nasko): Fix the following code to use a consistent set of data
  76     // across the URL, title, and favicon.
  77     url = web_contents->GetURL();
  78     title = base::UTF16ToUTF8(web_contents->GetTitle());
  79     NavigationController& controller = web_contents->GetController();
  80     NavigationEntry* entry = controller.GetVisibleEntry();
  81     if (entry != NULL && entry->GetURL().is_valid())
  82       favicon_url = entry->GetFavicon().url;
  83     accessibility_mode = web_contents->GetAccessibilityMode();
  84   }
  85
  86   return BuildTargetDescriptor(url,
  87                                title,
  88                                favicon_url,
  89                                rvh->GetProcess()->GetID(),
  90                                rvh->GetRoutingID(),
  91                                accessibility_mode);
  92 }
  93
  94 bool HandleRequestCallback(BrowserContext* current_context,
  95                            const std::string& path,
  96                            const WebUIDataSource::GotDataCallback& callback) {
  97   if (path != kDataFile)
  98     return false;
  99   scoped_ptr<base::ListValue> rvh_list(new base::ListValue());
 100
 101   scoped_ptr<RenderWidgetHostIterator> widgets(
 102       RenderWidgetHost::GetRenderWidgetHosts());
 103
 104   while (RenderWidgetHost* widget = widgets->GetNextHost()) {
 105     // Ignore processes that don't have a connection, such as crashed tabs.
 106     if (!widget->GetProcess()->HasConnection())
 107       continue;
 108     if (!widget->IsRenderView())
 109         continue;
 110     RenderWidgetHostImpl* rwhi = RenderWidgetHostImpl::From(widget);
 111     BrowserContext* context = rwhi->GetProcess()->GetBrowserContext();
 112     if (context != current_context)
 113       continue;
 114
 115     RenderViewHost* rvh = RenderViewHost::From(widget);
 116     rvh_list->Append(BuildTargetDescriptor(rvh));
 117   }
 118
 119   scoped_ptr<base::DictionaryValue> data(new base::DictionaryValue());
 120   data->Set("list", rvh_list.release());
 121   data->SetInteger(
 122       "global_a11y_mode",
 123       BrowserAccessibilityStateImpl::GetInstance()->accessibility_mode());
 124
 125   std::string json_string;
 126   base::JSONWriter::Write(data.get(), &json_string);
 127
 128   callback.Run(base::RefCountedString::TakeString(&json_string));
 129   return true;
 130 }
 131
 132 }  // namespace
 133
 134 AccessibilityUI::AccessibilityUI(WebUI* web_ui) : WebUIController(web_ui) {
 135   // Set up the chrome://accessibility source.
 136   WebUIDataSource* html_source =
 137       WebUIDataSource::Create(kChromeUIAccessibilityHost);
 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(
 158       base::Bind(&HandleRequestCallback,
 159                  web_ui->GetWebContents()->GetBrowserContext()));
 160
 161   BrowserContext* browser_context =
 162       web_ui->GetWebContents()->GetBrowserContext();
 163   WebUIDataSource::Add(browser_context, html_source);
 164 }
 165
 166 AccessibilityUI::~AccessibilityUI() {}
 167
 168 void AccessibilityUI::ToggleAccessibility(const base::ListValue* args) {
 169   std::string process_id_str;
 170   std::string route_id_str;
 171   int process_id;
 172   int route_id;
 173   CHECK_EQ(2U, args->GetSize());
 174   CHECK(args->GetString(0, &process_id_str));
 175   CHECK(args->GetString(1, &route_id_str));
 176   CHECK(base::StringToInt(process_id_str, &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   WebContentsImpl* web_contents = static_cast<WebContentsImpl*>(
 183       WebContents::FromRenderViewHost(rvh));
 184   AccessibilityMode mode = web_contents->GetAccessibilityMode();
 185   if ((mode & AccessibilityModeComplete) != AccessibilityModeComplete) {
 186     web_contents->AddAccessibilityMode(AccessibilityModeComplete);
 187   } else {
 188     web_contents->SetAccessibilityMode(
 189         BrowserAccessibilityStateImpl::GetInstance()->accessibility_mode());
 190   }
 191 }
 192
 193 void AccessibilityUI::ToggleGlobalAccessibility(const base::ListValue* args) {
 194   BrowserAccessibilityStateImpl* state =
 195       BrowserAccessibilityStateImpl::GetInstance();
 196   AccessibilityMode mode = state->accessibility_mode();
 197   if ((mode & AccessibilityModeComplete) != AccessibilityModeComplete)
 198     state->EnableAccessibility();
 199   else
 200     state->DisableAccessibility();
 201 }
 202
 203 void AccessibilityUI::RequestAccessibilityTree(const base::ListValue* args) {
 204   std::string process_id_str;
 205   std::string route_id_str;
 206   int process_id;
 207   int route_id;
 208   CHECK_EQ(2U, args->GetSize());
 209   CHECK(args->GetString(0, &process_id_str));
 210   CHECK(args->GetString(1, &route_id_str));
 211   CHECK(base::StringToInt(process_id_str, &process_id));
 212   CHECK(base::StringToInt(route_id_str, &route_id));
 213
 214   RenderViewHost* rvh = RenderViewHost::FromID(process_id, route_id);
 215   if (!rvh) {
 216     scoped_ptr<base::DictionaryValue> result(new base::DictionaryValue());
 217     result->SetInteger(kProcessIdField, process_id);
 218     result->SetInteger(kRouteIdField, route_id);
 219     result->Set("error", new base::StringValue("Renderer no longer exists."));
 220     web_ui()->CallJavascriptFunction("accessibility.showTree", *(result.get()));
 221     return;
 222   }
 223
 224   scoped_ptr<base::DictionaryValue> result(BuildTargetDescriptor(rvh));
 225   WebContents* web_contents = WebContents::FromRenderViewHost(rvh);
 226   scoped_ptr<AccessibilityTreeFormatter> formatter(
 227       AccessibilityTreeFormatter::Create(web_contents));
 228   base::string16 accessibility_contents_utf16;
 229   std::vector<AccessibilityTreeFormatter::Filter> filters;
 230   filters.push_back(AccessibilityTreeFormatter::Filter(
 231       base::ASCIIToUTF16("*"),
 232       AccessibilityTreeFormatter::Filter::ALLOW));
 233   formatter->SetFilters(filters);
 234   formatter->FormatAccessibilityTree(&accessibility_contents_utf16);
 235
 236   result->Set("tree",
 237               new base::StringValue(
 238                   base::UTF16ToUTF8(accessibility_contents_utf16)));
 239   web_ui()->CallJavascriptFunction("accessibility.showTree", *(result.get()));
 240 }
 241
 242 }  // namespace content