accessible/ipc/DocAccessibleChild.cpp

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #include "chrome/common/ipc_channel.h"
   8 #include "mozilla/a11y/DocAccessibleChild.h"
   9 #include "mozilla/a11y/CacheConstants.h"
  10 #include "mozilla/a11y/FocusManager.h"
  11 #include "mozilla/ipc/ProcessChild.h"
  12 #include "nsAccessibilityService.h"
  13
  14 #include "LocalAccessible-inl.h"
  15 #ifdef A11Y_LOG
  16 #  include "Logging.h"
  17 #endif
  18 #include "TextLeafRange.h"
  19
  20 namespace mozilla {
  21 namespace a11y {
  22
  23 /* static */
  24 void DocAccessibleChild::FlattenTree(LocalAccessible* aRoot,
  25                                      nsTArray<LocalAccessible*>& aTree) {
  26   MOZ_ASSERT(!aRoot->IsDoc(), "documents shouldn't be serialized");
  27
  28   aTree.AppendElement(aRoot);
  29   // OuterDocAccessibles are special because we don't want to serialize the
  30   // child doc here, we'll call PDocAccessibleConstructor in
  31   // NotificationController.
  32   uint32_t childCount = aRoot->IsOuterDoc() ? 0 : aRoot->ChildCount();
  33
  34   for (uint32_t i = 0; i < childCount; i++) {
  35     FlattenTree(aRoot->LocalChildAt(i), aTree);
  36   }
  37 }
  38
  39 /* static */
  40 AccessibleData DocAccessibleChild::SerializeAcc(LocalAccessible* aAcc) {
  41   uint32_t genericTypes = aAcc->mGenericTypes;
  42   if (aAcc->ARIAHasNumericValue()) {
  43     // XXX: We need to do this because this requires a state check.
  44     genericTypes |= eNumericValue;
  45   }
  46   if (aAcc->IsTextLeaf() || aAcc->IsImage()) {
  47     // Ideally, we'd set eActionable for any Accessible with an ancedstor
  48     // action. However, that requires an ancestor walk which is too expensive
  49     // here. eActionable is only used by ATK. For now, we only expose ancestor
  50     // actions on text leaf and image Accessibles. This means that we don't
  51     // support "click ancestor" for ATK.
  52     if (aAcc->ActionCount()) {
  53       genericTypes |= eActionable;
  54     }
  55   } else if (aAcc->HasPrimaryAction()) {
  56     genericTypes |= eActionable;
  57   }
  58
  59   RefPtr<AccAttributes> fields;
  60   // Even though we send moves as a hide and a show, we don't want to
  61   // push the cache again for moves.
  62   if (!aAcc->Document()->IsAccessibleBeingMoved(aAcc)) {
  63     fields =
  64         aAcc->BundleFieldsForCache(CacheDomain::All, CacheUpdateType::Initial);
  65     if (fields->Count() == 0) {
  66       fields = nullptr;
  67     }
  68   }
  69
  70   return AccessibleData(aAcc->ID(), aAcc->Role(), aAcc->LocalParent()->ID(),
  71                         static_cast<int32_t>(aAcc->IndexInParent()),
  72                         static_cast<AccType>(aAcc->mType),
  73                         static_cast<AccGenericType>(genericTypes),
  74                         aAcc->mRoleMapEntryIndex, fields);
  75 }
  76
  77 void DocAccessibleChild::InsertIntoIpcTree(LocalAccessible* aChild,
  78                                            bool aSuppressShowEvent) {
  79   nsTArray<LocalAccessible*> shownTree;
  80   FlattenTree(aChild, shownTree);
  81   uint32_t totalAccs = shownTree.Length();
  82   // Exceeding the IPDL maximum message size will cause a crash. Try to avoid
  83   // this by only including kMaxAccsPerMessage Accessibels in a single IPDL
  84   // call. If there are Accessibles beyond this, they will be split across
  85   // multiple calls.
  86   constexpr uint32_t kMaxAccsPerMessage =
  87       IPC::Channel::kMaximumMessageSize / (2 * 1024);
  88   nsTArray<AccessibleData> data(std::min(kMaxAccsPerMessage, totalAccs));
  89   for (LocalAccessible* child : shownTree) {
  90     if (data.Length() == kMaxAccsPerMessage) {
  91       if (ipc::ProcessChild::ExpectingShutdown()) {
  92         return;
  93       }
  94       SendShowEvent(data, aSuppressShowEvent, false, false);
  95       data.ClearAndRetainStorage();
  96     }
  97     data.AppendElement(SerializeAcc(child));
  98   }
  99   if (ipc::ProcessChild::ExpectingShutdown()) {
 100     return;
 101   }
 102   if (!data.IsEmpty()) {
 103     SendShowEvent(data, aSuppressShowEvent, true, false);
 104   }
 105 }
 106
 107 void DocAccessibleChild::ShowEvent(AccShowEvent* aShowEvent) {
 108   LocalAccessible* child = aShowEvent->GetAccessible();
 109   InsertIntoIpcTree(child, false);
 110 }
 111
 112 mozilla::ipc::IPCResult DocAccessibleChild::RecvTakeFocus(const uint64_t& aID) {
 113   LocalAccessible* acc = IdToAccessible(aID);
 114   if (acc) {
 115     acc->TakeFocus();
 116   }
 117   return IPC_OK();
 118 }
 119
 120 mozilla::ipc::IPCResult DocAccessibleChild::RecvScrollTo(
 121     const uint64_t& aID, const uint32_t& aScrollType) {
 122   LocalAccessible* acc = IdToAccessible(aID);
 123   if (acc) {
 124     RefPtr<PresShell> presShell = acc->Document()->PresShellPtr();
 125     nsCOMPtr<nsIContent> content = acc->GetContent();
 126     nsCoreUtils::ScrollTo(presShell, content, aScrollType);
 127   }
 128
 129   return IPC_OK();
 130 }
 131
 132 mozilla::ipc::IPCResult DocAccessibleChild::RecvTakeSelection(
 133     const uint64_t& aID) {
 134   LocalAccessible* acc = IdToAccessible(aID);
 135   if (acc) {
 136     acc->TakeSelection();
 137   }
 138
 139   return IPC_OK();
 140 }
 141
 142 mozilla::ipc::IPCResult DocAccessibleChild::RecvSetSelected(
 143     const uint64_t& aID, const bool& aSelect) {
 144   LocalAccessible* acc = IdToAccessible(aID);
 145   if (acc) {
 146     acc->SetSelected(aSelect);
 147   }
 148
 149   return IPC_OK();
 150 }
 151
 152 mozilla::ipc::IPCResult DocAccessibleChild::RecvVerifyCache(
 153     const uint64_t& aID, const uint64_t& aCacheDomain, AccAttributes* aFields) {
 154 #ifdef A11Y_LOG
 155   LocalAccessible* acc = IdToAccessible(aID);
 156   if (!acc) {
 157     return IPC_OK();
 158   }
 159
 160   RefPtr<AccAttributes> localFields =
 161       acc->BundleFieldsForCache(aCacheDomain, CacheUpdateType::Update);
 162   bool mismatches = false;
 163
 164   for (auto prop : *localFields) {
 165     if (prop.Value<DeleteEntry>()) {
 166       if (aFields->HasAttribute(prop.Name())) {
 167         if (!mismatches) {
 168           logging::MsgBegin("Mismatch!", "Local and remote values differ");
 169           logging::AccessibleInfo("", acc);
 170           mismatches = true;
 171         }
 172         nsAutoCString propName;
 173         prop.Name()->ToUTF8String(propName);
 174         nsAutoString val;
 175         aFields->GetAttribute(prop.Name(), val);
 176         logging::MsgEntry(
 177             "Remote value for %s should be empty, but instead it is '%s'",
 178             propName.get(), NS_ConvertUTF16toUTF8(val).get());
 179       }
 180       continue;
 181     }
 182
 183     nsAutoString localVal;
 184     prop.ValueAsString(localVal);
 185     nsAutoString remoteVal;
 186     aFields->GetAttribute(prop.Name(), remoteVal);
 187     if (!localVal.Equals(remoteVal)) {
 188       if (!mismatches) {
 189         logging::MsgBegin("Mismatch!", "Local and remote values differ");
 190         logging::AccessibleInfo("", acc);
 191         mismatches = true;
 192       }
 193       nsAutoCString propName;
 194       prop.Name()->ToUTF8String(propName);
 195       logging::MsgEntry("Fields differ: %s '%s' != '%s'", propName.get(),
 196                         NS_ConvertUTF16toUTF8(remoteVal).get(),
 197                         NS_ConvertUTF16toUTF8(localVal).get());
 198     }
 199   }
 200   if (mismatches) {
 201     logging::MsgEnd();
 202   }
 203 #endif  // A11Y_LOG
 204
 205   return IPC_OK();
 206 }
 207
 208 mozilla::ipc::IPCResult DocAccessibleChild::RecvDoActionAsync(
 209     const uint64_t& aID, const uint8_t& aIndex) {
 210   if (LocalAccessible* acc = IdToAccessible(aID)) {
 211     Unused << acc->DoAction(aIndex);
 212   }
 213
 214   return IPC_OK();
 215 }
 216
 217 mozilla::ipc::IPCResult DocAccessibleChild::RecvSetCaretOffset(
 218     const uint64_t& aID, const int32_t& aOffset) {
 219   HyperTextAccessible* acc = IdToHyperTextAccessible(aID);
 220   if (acc && acc->IsTextRole() && acc->IsValidOffset(aOffset)) {
 221     acc->SetCaretOffset(aOffset);
 222   }
 223   return IPC_OK();
 224 }
 225
 226 mozilla::ipc::IPCResult DocAccessibleChild::RecvSetTextSelection(
 227     const uint64_t& aStartID, const int32_t& aStartOffset,
 228     const uint64_t& aEndID, const int32_t& aEndOffset,
 229     const int32_t& aSelectionNum) {
 230   TextLeafRange range(TextLeafPoint(IdToAccessible(aStartID), aStartOffset),
 231                       TextLeafPoint(IdToAccessible(aEndID), aEndOffset));
 232   if (range) {
 233     range.SetSelection(aSelectionNum);
 234   }
 235
 236   return IPC_OK();
 237 }
 238
 239 mozilla::ipc::IPCResult DocAccessibleChild::RecvScrollTextLeafRangeIntoView(
 240     const uint64_t& aStartID, const int32_t& aStartOffset,
 241     const uint64_t& aEndID, const int32_t& aEndOffset,
 242     const uint32_t& aScrollType) {
 243   TextLeafRange range(TextLeafPoint(IdToAccessible(aStartID), aStartOffset),
 244                       TextLeafPoint(IdToAccessible(aEndID), aEndOffset));
 245   if (range) {
 246     range.ScrollIntoView(aScrollType);
 247   }
 248
 249   return IPC_OK();
 250 }
 251
 252 mozilla::ipc::IPCResult DocAccessibleChild::RecvRemoveTextSelection(
 253     const uint64_t& aID, const int32_t& aSelectionNum) {
 254   HyperTextAccessible* acc = IdToHyperTextAccessible(aID);
 255   if (acc && acc->IsTextRole()) {
 256     acc->RemoveFromSelection(aSelectionNum);
 257   }
 258
 259   return IPC_OK();
 260 }
 261
 262 mozilla::ipc::IPCResult DocAccessibleChild::RecvSetCurValue(
 263     const uint64_t& aID, const double& aValue) {
 264   LocalAccessible* acc = IdToAccessible(aID);
 265   if (acc) {
 266     acc->SetCurValue(aValue);
 267   }
 268
 269   return IPC_OK();
 270 }
 271
 272 mozilla::ipc::IPCResult DocAccessibleChild::RecvReplaceText(
 273     const uint64_t& aID, const nsAString& aText) {
 274   HyperTextAccessible* acc = IdToHyperTextAccessible(aID);
 275   if (acc && acc->IsTextRole()) {
 276     acc->ReplaceText(aText);
 277   }
 278
 279   return IPC_OK();
 280 }
 281
 282 mozilla::ipc::IPCResult DocAccessibleChild::RecvInsertText(
 283     const uint64_t& aID, const nsAString& aText, const int32_t& aPosition) {
 284   HyperTextAccessible* acc = IdToHyperTextAccessible(aID);
 285   if (acc && acc->IsTextRole()) {
 286     acc->InsertText(aText, aPosition);
 287   }
 288
 289   return IPC_OK();
 290 }
 291
 292 mozilla::ipc::IPCResult DocAccessibleChild::RecvCopyText(
 293     const uint64_t& aID, const int32_t& aStartPos, const int32_t& aEndPos) {
 294   HyperTextAccessible* acc = IdToHyperTextAccessible(aID);
 295   if (acc && acc->IsTextRole()) {
 296     acc->CopyText(aStartPos, aEndPos);
 297   }
 298
 299   return IPC_OK();
 300 }
 301
 302 mozilla::ipc::IPCResult DocAccessibleChild::RecvCutText(
 303     const uint64_t& aID, const int32_t& aStartPos, const int32_t& aEndPos) {
 304   HyperTextAccessible* acc = IdToHyperTextAccessible(aID);
 305   if (acc && acc->IsTextRole()) {
 306     acc->CutText(aStartPos, aEndPos);
 307   }
 308
 309   return IPC_OK();
 310 }
 311
 312 mozilla::ipc::IPCResult DocAccessibleChild::RecvDeleteText(
 313     const uint64_t& aID, const int32_t& aStartPos, const int32_t& aEndPos) {
 314   HyperTextAccessible* acc = IdToHyperTextAccessible(aID);
 315   if (acc && acc->IsTextRole()) {
 316     acc->DeleteText(aStartPos, aEndPos);
 317   }
 318
 319   return IPC_OK();
 320 }
 321
 322 mozilla::ipc::IPCResult DocAccessibleChild::RecvPasteText(
 323     const uint64_t& aID, const int32_t& aPosition) {
 324   RefPtr<HyperTextAccessible> acc = IdToHyperTextAccessible(aID);
 325   if (acc && acc->IsTextRole()) {
 326     acc->PasteText(aPosition);
 327   }
 328
 329   return IPC_OK();
 330 }
 331
 332 ipc::IPCResult DocAccessibleChild::RecvRestoreFocus() {
 333   if (FocusManager* focusMgr = FocusMgr()) {
 334     focusMgr->ForceFocusEvent();
 335   }
 336   return IPC_OK();
 337 }
 338
 339 mozilla::ipc::IPCResult DocAccessibleChild::RecvScrollToPoint(
 340     const uint64_t& aID, const uint32_t& aScrollType, const int32_t& aX,
 341     const int32_t& aY) {
 342   LocalAccessible* acc = IdToAccessible(aID);
 343   if (acc) {
 344     acc->ScrollToPoint(aScrollType, aX, aY);
 345   }
 346
 347   return IPC_OK();
 348 }
 349
 350 LayoutDeviceIntRect DocAccessibleChild::GetCaretRectFor(const uint64_t& aID) {
 351 #if defined(XP_WIN)
 352   LocalAccessible* target;
 353
 354   if (aID) {
 355     target = reinterpret_cast<LocalAccessible*>(aID);
 356   } else {
 357     target = mDoc;
 358   }
 359
 360   MOZ_ASSERT(target);
 361
 362   HyperTextAccessible* text = target->AsHyperText();
 363   if (!text) {
 364     return LayoutDeviceIntRect();
 365   }
 366
 367   nsIWidget* widget = nullptr;
 368   return text->GetCaretRect(&widget);
 369 #else
 370   // The caret rect is only used on Windows, so just return an empty rect
 371   // on other platforms.
 372   return LayoutDeviceIntRect();
 373 #endif  // defined(XP_WIN)
 374 }
 375
 376 bool DocAccessibleChild::SendFocusEvent(const uint64_t& aID) {
 377   return PDocAccessibleChild::SendFocusEvent(aID, GetCaretRectFor(aID));
 378 }
 379
 380 bool DocAccessibleChild::SendCaretMoveEvent(const uint64_t& aID,
 381                                             const int32_t& aOffset,
 382                                             const bool& aIsSelectionCollapsed,
 383                                             const bool& aIsAtEndOfLine,
 384                                             const int32_t& aGranularity) {
 385   return PDocAccessibleChild::SendCaretMoveEvent(aID, GetCaretRectFor(aID),
 386                                                  aOffset, aIsSelectionCollapsed,
 387                                                  aIsAtEndOfLine, aGranularity);
 388 }
 389
 390 #if !defined(XP_WIN)
 391 mozilla::ipc::IPCResult DocAccessibleChild::RecvAnnounce(
 392     const uint64_t& aID, const nsAString& aAnnouncement,
 393     const uint16_t& aPriority) {
 394   LocalAccessible* acc = IdToAccessible(aID);
 395   if (acc) {
 396     acc->Announce(aAnnouncement, aPriority);
 397   }
 398
 399   return IPC_OK();
 400 }
 401 #endif  // !defined(XP_WIN)
 402
 403 mozilla::ipc::IPCResult DocAccessibleChild::RecvScrollSubstringToPoint(
 404     const uint64_t& aID, const int32_t& aStartOffset, const int32_t& aEndOffset,
 405     const uint32_t& aCoordinateType, const int32_t& aX, const int32_t& aY) {
 406   HyperTextAccessible* acc = IdToHyperTextAccessible(aID);
 407   if (acc) {
 408     acc->ScrollSubstringToPoint(aStartOffset, aEndOffset, aCoordinateType, aX,
 409                                 aY);
 410   }
 411
 412   return IPC_OK();
 413 }
 414
 415 LocalAccessible* DocAccessibleChild::IdToAccessible(const uint64_t& aID) const {
 416   if (!aID) return mDoc;
 417
 418   if (!mDoc) return nullptr;
 419
 420   return mDoc->GetAccessibleByUniqueID(reinterpret_cast<void*>(aID));
 421 }
 422
 423 HyperTextAccessible* DocAccessibleChild::IdToHyperTextAccessible(
 424     const uint64_t& aID) const {
 425   LocalAccessible* acc = IdToAccessible(aID);
 426   return acc && acc->IsHyperText() ? acc->AsHyperText() : nullptr;
 427 }
 428
 429 }  // namespace a11y
 430 }  // namespace mozilla