dom/xbl/nsXBLWindowKeyHandler.cpp

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 #include "nsCOMPtr.h"
   7 #include "nsXBLPrototypeHandler.h"
   8 #include "nsXBLWindowKeyHandler.h"
   9 #include "nsIContent.h"
  10 #include "nsIAtom.h"
  11 #include "nsIDOMKeyEvent.h"
  12 #include "nsXBLService.h"
  13 #include "nsIServiceManager.h"
  14 #include "nsGkAtoms.h"
  15 #include "nsXBLDocumentInfo.h"
  16 #include "nsIDOMElement.h"
  17 #include "nsFocusManager.h"
  18 #include "nsIURI.h"
  19 #include "nsNetUtil.h"
  20 #include "nsContentUtils.h"
  21 #include "nsXBLPrototypeBinding.h"
  22 #include "nsPIDOMWindow.h"
  23 #include "nsIDocShell.h"
  24 #include "nsIPresShell.h"
  25 #include "mozilla/EventStateManager.h"
  26 #include "nsISelectionController.h"
  27 #include "mozilla/Preferences.h"
  28 #include "mozilla/TextEvents.h"
  29 #include "mozilla/dom/Element.h"
  30 #include "mozilla/dom/Event.h"
  31 #include "nsIEditor.h"
  32 #include "nsIHTMLEditor.h"
  33 #include "nsIDOMDocument.h"
  34
  35 using namespace mozilla;
  36 using namespace mozilla::dom;
  37
  38 class nsXBLSpecialDocInfo : public nsIObserver
  39 {
  40 public:
  41   nsRefPtr<nsXBLDocumentInfo> mHTMLBindings;
  42   nsRefPtr<nsXBLDocumentInfo> mUserHTMLBindings;
  43
  44   static const char sHTMLBindingStr[];
  45   static const char sUserHTMLBindingStr[];
  46
  47   bool mInitialized;
  48
  49 public:
  50   NS_DECL_ISUPPORTS
  51   NS_DECL_NSIOBSERVER
  52
  53   void LoadDocInfo();
  54   void GetAllHandlers(const char* aType,
  55                       nsXBLPrototypeHandler** handler,
  56                       nsXBLPrototypeHandler** userHandler);
  57   void GetHandlers(nsXBLDocumentInfo* aInfo,
  58                    const nsACString& aRef,
  59                    nsXBLPrototypeHandler** aResult);
  60
  61   nsXBLSpecialDocInfo() : mInitialized(false) {}
  62
  63 protected:
  64   virtual ~nsXBLSpecialDocInfo() {}
  65
  66 };
  67
  68 const char nsXBLSpecialDocInfo::sHTMLBindingStr[] =
  69   "chrome://global/content/platformHTMLBindings.xml";
  70
  71 NS_IMPL_ISUPPORTS(nsXBLSpecialDocInfo, nsIObserver)
  72
  73 NS_IMETHODIMP
  74 nsXBLSpecialDocInfo::Observe(nsISupports* aSubject,
  75                              const char* aTopic,
  76                              const char16_t* aData)
  77 {
  78   MOZ_ASSERT(!strcmp(aTopic, "xpcom-shutdown"), "wrong topic");
  79
  80   // On shutdown, clear our fields to avoid an extra cycle collection.
  81   mHTMLBindings = nullptr;
  82   mUserHTMLBindings = nullptr;
  83   mInitialized = false;
  84   nsContentUtils::UnregisterShutdownObserver(this);
  85
  86   return NS_OK;
  87 }
  88
  89 void nsXBLSpecialDocInfo::LoadDocInfo()
  90 {
  91   if (mInitialized)
  92     return;
  93   mInitialized = true;
  94   nsContentUtils::RegisterShutdownObserver(this);
  95
  96   nsXBLService* xblService = nsXBLService::GetInstance();
  97   if (!xblService)
  98     return;
  99
 100   // Obtain the platform doc info
 101   nsCOMPtr<nsIURI> bindingURI;
 102   NS_NewURI(getter_AddRefs(bindingURI), sHTMLBindingStr);
 103   if (!bindingURI) {
 104     return;
 105   }
 106   xblService->LoadBindingDocumentInfo(nullptr, nullptr,
 107                                       bindingURI,
 108                                       nullptr,
 109                                       true,
 110                                       getter_AddRefs(mHTMLBindings));
 111
 112   const nsAdoptingCString& userHTMLBindingStr =
 113     Preferences::GetCString("dom.userHTMLBindings.uri");
 114   if (!userHTMLBindingStr.IsEmpty()) {
 115     NS_NewURI(getter_AddRefs(bindingURI), userHTMLBindingStr);
 116     if (!bindingURI) {
 117       return;
 118     }
 119
 120     xblService->LoadBindingDocumentInfo(nullptr, nullptr,
 121                                         bindingURI,
 122                                         nullptr,
 123                                         true,
 124                                         getter_AddRefs(mUserHTMLBindings));
 125   }
 126 }
 127
 128 //
 129 // GetHandlers
 130 //
 131 //
 132 void
 133 nsXBLSpecialDocInfo::GetHandlers(nsXBLDocumentInfo* aInfo,
 134                                  const nsACString& aRef,
 135                                  nsXBLPrototypeHandler** aResult)
 136 {
 137   nsXBLPrototypeBinding* binding = aInfo->GetPrototypeBinding(aRef);
 138
 139   NS_ASSERTION(binding, "No binding found for the XBL window key handler.");
 140   if (!binding)
 141     return;
 142
 143   *aResult = binding->GetPrototypeHandlers();
 144 }
 145
 146 void
 147 nsXBLSpecialDocInfo::GetAllHandlers(const char* aType,
 148                                     nsXBLPrototypeHandler** aHandler,
 149                                     nsXBLPrototypeHandler** aUserHandler)
 150 {
 151   if (mUserHTMLBindings) {
 152     nsAutoCString type(aType);
 153     type.AppendLiteral("User");
 154     GetHandlers(mUserHTMLBindings, type, aUserHandler);
 155   }
 156   if (mHTMLBindings) {
 157     GetHandlers(mHTMLBindings, nsDependentCString(aType), aHandler);
 158   }
 159 }
 160
 161 // Init statics
 162 nsXBLSpecialDocInfo* nsXBLWindowKeyHandler::sXBLSpecialDocInfo = nullptr;
 163 uint32_t nsXBLWindowKeyHandler::sRefCnt = 0;
 164
 165 nsXBLWindowKeyHandler::nsXBLWindowKeyHandler(nsIDOMElement* aElement,
 166                                              EventTarget* aTarget)
 167   : mTarget(aTarget),
 168     mHandler(nullptr),
 169     mUserHandler(nullptr)
 170 {
 171   mWeakPtrForElement = do_GetWeakReference(aElement);
 172   ++sRefCnt;
 173 }
 174
 175 nsXBLWindowKeyHandler::~nsXBLWindowKeyHandler()
 176 {
 177   // If mWeakPtrForElement is non-null, we created a prototype handler.
 178   if (mWeakPtrForElement)
 179     delete mHandler;
 180
 181   --sRefCnt;
 182   if (!sRefCnt) {
 183     NS_IF_RELEASE(sXBLSpecialDocInfo);
 184   }
 185 }
 186
 187 NS_IMPL_ISUPPORTS(nsXBLWindowKeyHandler,
 188                   nsIDOMEventListener)
 189
 190 static void
 191 BuildHandlerChain(nsIContent* aContent, nsXBLPrototypeHandler** aResult)
 192 {
 193   *aResult = nullptr;
 194
 195   // Since we chain each handler onto the next handler,
 196   // we'll enumerate them here in reverse so that when we
 197   // walk the chain they'll come out in the original order
 198   for (nsIContent* key = aContent->GetLastChild();
 199        key;
 200        key = key->GetPreviousSibling()) {
 201
 202     if (key->NodeInfo()->Equals(nsGkAtoms::key, kNameSpaceID_XUL)) {
 203       // Check whether the key element has empty value at key/char attribute.
 204       // Such element is used by localizers for alternative shortcut key
 205       // definition on the locale. See bug 426501.
 206       nsAutoString valKey, valCharCode, valKeyCode;
 207       bool attrExists =
 208         key->GetAttr(kNameSpaceID_None, nsGkAtoms::key, valKey) ||
 209         key->GetAttr(kNameSpaceID_None, nsGkAtoms::charcode, valCharCode) ||
 210         key->GetAttr(kNameSpaceID_None, nsGkAtoms::keycode, valKeyCode);
 211       if (attrExists &&
 212           valKey.IsEmpty() && valCharCode.IsEmpty() && valKeyCode.IsEmpty())
 213         continue;
 214
 215       nsXBLPrototypeHandler* handler = new nsXBLPrototypeHandler(key);
 216
 217       if (!handler)
 218         return;
 219
 220       handler->SetNextHandler(*aResult);
 221       *aResult = handler;
 222     }
 223   }
 224 }
 225
 226 //
 227 // EnsureHandlers
 228 //
 229 // Lazily load the XBL handlers. Overridden to handle being attached
 230 // to a particular element rather than the document
 231 //
 232 nsresult
 233 nsXBLWindowKeyHandler::EnsureHandlers()
 234 {
 235   nsCOMPtr<Element> el = GetElement();
 236   NS_ENSURE_STATE(!mWeakPtrForElement || el);
 237   if (el) {
 238     // We are actually a XUL <keyset>.
 239     if (mHandler)
 240       return NS_OK;
 241
 242     nsCOMPtr<nsIContent> content(do_QueryInterface(el));
 243     BuildHandlerChain(content, &mHandler);
 244   } else { // We are an XBL file of handlers.
 245     if (!sXBLSpecialDocInfo) {
 246       sXBLSpecialDocInfo = new nsXBLSpecialDocInfo();
 247       NS_ADDREF(sXBLSpecialDocInfo);
 248     }
 249     sXBLSpecialDocInfo->LoadDocInfo();
 250
 251     // Now determine which handlers we should be using.
 252     if (IsHTMLEditableFieldFocused()) {
 253       sXBLSpecialDocInfo->GetAllHandlers("editor", &mHandler, &mUserHandler);
 254     }
 255     else {
 256       sXBLSpecialDocInfo->GetAllHandlers("browser", &mHandler, &mUserHandler);
 257     }
 258   }
 259
 260   return NS_OK;
 261 }
 262
 263 nsresult
 264 nsXBLWindowKeyHandler::WalkHandlers(nsIDOMKeyEvent* aKeyEvent, nsIAtom* aEventType)
 265 {
 266   bool prevent;
 267   aKeyEvent->GetDefaultPrevented(&prevent);
 268   if (prevent)
 269     return NS_OK;
 270
 271   bool trustedEvent = false;
 272   // Don't process the event if it was not dispatched from a trusted source
 273   aKeyEvent->GetIsTrusted(&trustedEvent);
 274
 275   if (!trustedEvent)
 276     return NS_OK;
 277
 278   nsresult rv = EnsureHandlers();
 279   NS_ENSURE_SUCCESS(rv, rv);
 280
 281   bool isDisabled;
 282   nsCOMPtr<Element> el = GetElement(&isDisabled);
 283   if (!el) {
 284     if (mUserHandler) {
 285       WalkHandlersInternal(aKeyEvent, aEventType, mUserHandler, true);
 286       aKeyEvent->GetDefaultPrevented(&prevent);
 287       if (prevent)
 288         return NS_OK; // Handled by the user bindings. Our work here is done.
 289     }
 290   }
 291
 292   // skip keysets that are disabled
 293   if (el && isDisabled) {
 294     return NS_OK;
 295   }
 296
 297   WalkHandlersInternal(aKeyEvent, aEventType, mHandler, true);
 298
 299   return NS_OK;
 300 }
 301
 302 NS_IMETHODIMP
 303 nsXBLWindowKeyHandler::HandleEvent(nsIDOMEvent* aEvent)
 304 {
 305   nsCOMPtr<nsIDOMKeyEvent> keyEvent(do_QueryInterface(aEvent));
 306   NS_ENSURE_TRUE(keyEvent, NS_ERROR_INVALID_ARG);
 307
 308   uint16_t eventPhase;
 309   aEvent->GetEventPhase(&eventPhase);
 310   if (eventPhase == nsIDOMEvent::CAPTURING_PHASE) {
 311     HandleEventOnCapture(keyEvent);
 312     return NS_OK;
 313   }
 314
 315   nsAutoString eventType;
 316   aEvent->GetType(eventType);
 317   nsCOMPtr<nsIAtom> eventTypeAtom = do_GetAtom(eventType);
 318   NS_ENSURE_TRUE(eventTypeAtom, NS_ERROR_OUT_OF_MEMORY);
 319
 320   return WalkHandlers(keyEvent, eventTypeAtom);
 321 }
 322
 323 void
 324 nsXBLWindowKeyHandler::HandleEventOnCapture(nsIDOMKeyEvent* aEvent)
 325 {
 326   WidgetKeyboardEvent* widgetEvent =
 327     aEvent->GetInternalNSEvent()->AsKeyboardEvent();
 328
 329   if (widgetEvent->mFlags.mNoCrossProcessBoundaryForwarding) {
 330     return;
 331   }
 332
 333   nsCOMPtr<mozilla::dom::Element> originalTarget =
 334     do_QueryInterface(aEvent->GetInternalNSEvent()->originalTarget);
 335   if (!EventStateManager::IsRemoteTarget(originalTarget)) {
 336     return;
 337   }
 338
 339   if (!HasHandlerForEvent(aEvent)) {
 340     return;
 341   }
 342
 343   // If this event hasn't been marked as mNoCrossProcessBoundaryForwarding
 344   // yet, it means it wasn't processed by content. We'll not call any
 345   // of the handlers at this moment, and will wait for the event to be
 346   // redispatched with mNoCrossProcessBoundaryForwarding = 1 to process it.
 347
 348   // Inform the child process that this is a event that we want a reply
 349   // from.
 350   widgetEvent->mFlags.mWantReplyFromContentProcess = 1;
 351   aEvent->StopPropagation();
 352 }
 353
 354 //
 355 // EventMatched
 356 //
 357 // See if the given handler cares about this particular key event
 358 //
 359 bool
 360 nsXBLWindowKeyHandler::EventMatched(nsXBLPrototypeHandler* inHandler,
 361                                     nsIAtom* inEventType,
 362                                     nsIDOMKeyEvent* inEvent,
 363                                     uint32_t aCharCode, bool aIgnoreShiftKey)
 364 {
 365   return inHandler->KeyEventMatched(inEventType, inEvent, aCharCode,
 366                                     aIgnoreShiftKey);
 367 }
 368
 369 bool
 370 nsXBLWindowKeyHandler::IsHTMLEditableFieldFocused()
 371 {
 372   nsIFocusManager* fm = nsFocusManager::GetFocusManager();
 373   if (!fm)
 374     return false;
 375
 376   nsCOMPtr<nsIDOMWindow> focusedWindow;
 377   fm->GetFocusedWindow(getter_AddRefs(focusedWindow));
 378   if (!focusedWindow)
 379     return false;
 380
 381   nsCOMPtr<nsPIDOMWindow> piwin(do_QueryInterface(focusedWindow));
 382   nsIDocShell *docShell = piwin->GetDocShell();
 383   if (!docShell) {
 384     return false;
 385   }
 386
 387   nsCOMPtr<nsIEditor> editor;
 388   docShell->GetEditor(getter_AddRefs(editor));
 389   nsCOMPtr<nsIHTMLEditor> htmlEditor = do_QueryInterface(editor);
 390   if (!htmlEditor) {
 391     return false;
 392   }
 393
 394   nsCOMPtr<nsIDOMDocument> domDocument;
 395   editor->GetDocument(getter_AddRefs(domDocument));
 396   nsCOMPtr<nsIDocument> doc = do_QueryInterface(domDocument);
 397   if (doc->HasFlag(NODE_IS_EDITABLE)) {
 398     // Don't need to perform any checks in designMode documents.
 399     return true;
 400   }
 401
 402   nsCOMPtr<nsIDOMElement> focusedElement;
 403   fm->GetFocusedElement(getter_AddRefs(focusedElement));
 404   nsCOMPtr<nsINode> focusedNode = do_QueryInterface(focusedElement);
 405   if (focusedNode) {
 406     // If there is a focused element, make sure it's in the active editing host.
 407     // Note that GetActiveEditingHost finds the current editing host based on
 408     // the document's selection.  Even though the document selection is usually
 409     // collapsed to where the focus is, but the page may modify the selection
 410     // without our knowledge, in which case this check will do something useful.
 411     nsCOMPtr<Element> activeEditingHost = htmlEditor->GetActiveEditingHost();
 412     if (!activeEditingHost) {
 413       return false;
 414     }
 415     return nsContentUtils::ContentIsDescendantOf(focusedNode, activeEditingHost);
 416   }
 417
 418   return false;
 419 }
 420
 421 //
 422 // WalkHandlersInternal and WalkHandlersAndExecute
 423 //
 424 // Given a particular DOM event and a pointer to the first handler in the list,
 425 // scan through the list to find something to handle the event. If aExecute = true,
 426 // the handler will be executed; otherwise just return an answer telling if a handler
 427 // for that event was found.
 428 //
 429 bool
 430 nsXBLWindowKeyHandler::WalkHandlersInternal(nsIDOMKeyEvent* aKeyEvent,
 431                                             nsIAtom* aEventType,
 432                                             nsXBLPrototypeHandler* aHandler,
 433                                             bool aExecute)
 434 {
 435   nsAutoTArray<nsShortcutCandidate, 10> accessKeys;
 436   nsContentUtils::GetAccelKeyCandidates(aKeyEvent, accessKeys);
 437
 438   if (accessKeys.IsEmpty()) {
 439     return WalkHandlersAndExecute(aKeyEvent, aEventType, aHandler,
 440                                   0, false, aExecute);
 441   }
 442
 443   for (uint32_t i = 0; i < accessKeys.Length(); ++i) {
 444     nsShortcutCandidate &key = accessKeys[i];
 445     if (WalkHandlersAndExecute(aKeyEvent, aEventType, aHandler,
 446                                key.mCharCode, key.mIgnoreShift, aExecute))
 447       return true;
 448   }
 449   return false;
 450 }
 451
 452 bool
 453 nsXBLWindowKeyHandler::WalkHandlersAndExecute(nsIDOMKeyEvent* aKeyEvent,
 454                                               nsIAtom* aEventType,
 455                                               nsXBLPrototypeHandler* aHandler,
 456                                               uint32_t aCharCode,
 457                                               bool aIgnoreShiftKey,
 458                                               bool aExecute)
 459 {
 460   nsresult rv;
 461
 462   // Try all of the handlers until we find one that matches the event.
 463   for (nsXBLPrototypeHandler *currHandler = aHandler; currHandler;
 464        currHandler = currHandler->GetNextHandler()) {
 465     bool stopped = aKeyEvent->IsDispatchStopped();
 466     if (stopped) {
 467       // The event is finished, don't execute any more handlers
 468       return false;
 469     }
 470
 471     if (!EventMatched(currHandler, aEventType, aKeyEvent,
 472                       aCharCode, aIgnoreShiftKey))
 473       continue;  // try the next one
 474
 475     // Before executing this handler, check that it's not disabled,
 476     // and that it has something to do (oncommand of the <key> or its
 477     // <command> is non-empty).
 478     nsCOMPtr<nsIContent> elt = currHandler->GetHandlerElement();
 479     nsCOMPtr<Element> commandElt;
 480
 481     // See if we're in a XUL doc.
 482     nsCOMPtr<Element> el = GetElement();
 483     if (el && elt) {
 484       // We are.  Obtain our command attribute.
 485       nsAutoString command;
 486       elt->GetAttr(kNameSpaceID_None, nsGkAtoms::command, command);
 487       if (!command.IsEmpty()) {
 488         // Locate the command element in question.  Note that we
 489         // know "elt" is in a doc if we're dealing with it here.
 490         NS_ASSERTION(elt->IsInDoc(), "elt must be in document");
 491         nsIDocument *doc = elt->GetCurrentDoc();
 492         if (doc)
 493           commandElt = do_QueryInterface(doc->GetElementById(command));
 494
 495         if (!commandElt) {
 496           NS_ERROR("A XUL <key> is observing a command that doesn't exist. Unable to execute key binding!");
 497           continue;
 498         }
 499       }
 500     }
 501
 502     if (!commandElt) {
 503       commandElt = do_QueryInterface(elt);
 504     }
 505
 506     if (commandElt) {
 507       nsAutoString value;
 508       commandElt->GetAttribute(NS_LITERAL_STRING("disabled"), value);
 509       if (value.EqualsLiteral("true")) {
 510         continue;  // this handler is disabled, try the next one
 511       }
 512
 513       // Check that there is an oncommand handler
 514       commandElt->GetAttribute(NS_LITERAL_STRING("oncommand"), value);
 515       if (value.IsEmpty()) {
 516         continue;  // nothing to do
 517       }
 518     }
 519
 520     nsCOMPtr<EventTarget> piTarget;
 521     nsCOMPtr<Element> element = GetElement();
 522     if (element) {
 523       piTarget = commandElt;
 524     } else {
 525       piTarget = mTarget;
 526     }
 527
 528     if (!aExecute) {
 529       return true;
 530     }
 531
 532     rv = currHandler->ExecuteHandler(piTarget, aKeyEvent);
 533     if (NS_SUCCEEDED(rv)) {
 534       return true;
 535     }
 536   }
 537
 538   return false;
 539 }
 540
 541 bool
 542 nsXBLWindowKeyHandler::HasHandlerForEvent(nsIDOMKeyEvent* aEvent)
 543 {
 544   if (!aEvent->InternalDOMEvent()->IsTrusted()) {
 545     return false;
 546   }
 547
 548   nsresult rv = EnsureHandlers();
 549   NS_ENSURE_SUCCESS(rv, false);
 550
 551   bool isDisabled;
 552   nsCOMPtr<Element> el = GetElement(&isDisabled);
 553   if (el && isDisabled) {
 554     return false;
 555   }
 556
 557   nsAutoString eventType;
 558   aEvent->GetType(eventType);
 559   nsCOMPtr<nsIAtom> eventTypeAtom = do_GetAtom(eventType);
 560   NS_ENSURE_TRUE(eventTypeAtom, false);
 561
 562   return WalkHandlersInternal(aEvent, eventTypeAtom, mHandler, false);
 563 }
 564
 565 already_AddRefed<Element>
 566 nsXBLWindowKeyHandler::GetElement(bool* aIsDisabled)
 567 {
 568   nsCOMPtr<Element> element = do_QueryReferent(mWeakPtrForElement);
 569   if (element && aIsDisabled) {
 570     *aIsDisabled = element->AttrValueIs(kNameSpaceID_None, nsGkAtoms::disabled,
 571                                         nsGkAtoms::_true, eCaseMatters);
 572   }
 573   return element.forget();
 574 }
 575
 576 ///////////////////////////////////////////////////////////////////////////////////
 577
 578 already_AddRefed<nsXBLWindowKeyHandler>
 579 NS_NewXBLWindowKeyHandler(nsIDOMElement* aElement, EventTarget* aTarget)
 580 {
 581   nsRefPtr<nsXBLWindowKeyHandler> result =
 582     new nsXBLWindowKeyHandler(aElement, aTarget);
 583   return result.forget();
 584 }