Commit 294c5068 authored by Masayuki Nakano's avatar Masayuki Nakano
Browse files

Bug 1815969 - part 1: Redesign `EditorBase::FireClipboardEvent` r=m_kato 

It does not handle critical cases properly, and it uses an out-param.
We can rewrite it with `Result`.  However, unfortunately,
`nsCopySupport::FireClipboardEvent` does not return error.  Therefore,
the root callers still need to treat the error cases as "canceled".

Differential Revision: https://phabricator.services.mozilla.com/D176737
parent 32c74afb

accessible/generic/HyperTextAccessible.h

+1 −1
Original line number Diff line number Diff line
@@ -243,7 +243,7 @@ class HyperTextAccessible : public AccessibleWrap, 
  MOZ_CAN_RUN_SCRIPT_BOUNDARY void ReplaceText(const nsAString& aText);

  MOZ_CAN_RUN_SCRIPT_BOUNDARY void InsertText(const nsAString& aText,

                                              int32_t aPosition);

  void CopyText(int32_t aStartPos, int32_t aEndPos);

  MOZ_CAN_RUN_SCRIPT_BOUNDARY void CopyText(int32_t aStartPos, int32_t aEndPos);

  MOZ_CAN_RUN_SCRIPT_BOUNDARY void CutText(int32_t aStartPos, int32_t aEndPos);

  MOZ_CAN_RUN_SCRIPT_BOUNDARY void DeleteText(int32_t aStartPos,

                                              int32_t aEndPos);

editor/libeditor/EditorBase.cpp

+85 −25
Original line number Diff line number Diff line
@@ -33,6 +33,7 @@ 


#include "ErrorList.h"

#include "gfxFontUtils.h"  // for gfxFontUtils

#include "mozilla/Assertions.h"

#include "mozilla/intl/BidiEmbeddingLevel.h"

#include "mozilla/BasePrincipal.h"            // for BasePrincipal

#include "mozilla/CheckedInt.h"               // for CheckedInt
@@ -1578,35 +1579,64 @@ bool EditorBase::CheckForClipboardCommandListener( 
  return false;

}



bool EditorBase::FireClipboardEvent(EventMessage aEventMessage,

                                    int32_t aClipboardType,

                                    bool* aActionTaken) {

Result<EditorBase::ClipboardEventResult, nsresult>

EditorBase::DispatchClipboardEventAndUpdateClipboard(EventMessage aEventMessage,

                                                     int32_t aClipboardType) {

  MOZ_ASSERT(IsEditActionDataAvailable());



  if (aEventMessage == ePaste) {

    CommitComposition();

    if (NS_WARN_IF(Destroyed())) {

      return Err(NS_ERROR_EDITOR_DESTROYED);

    }

  }



  RefPtr<PresShell> presShell = GetPresShell();

  if (NS_WARN_IF(!presShell)) {

    return false;

    return Err(NS_ERROR_NOT_AVAILABLE);

  }



  RefPtr<Selection> sel = &SelectionRef();

  if (IsHTMLEditor() && aEventMessage == eCopy && sel->IsCollapsed()) {

    // If we don't have a usable selection for copy and we're an HTML editor

    // (which is global for the document) try to use the last focused selection

    // instead.

    sel = nsCopySupport::GetSelectionForCopy(GetDocument());

  const RefPtr<Selection> sel = [&]() {

    if (IsHTMLEditor() && aEventMessage == eCopy &&

        SelectionRef().IsCollapsed()) {

      // If we don't have a usable selection for copy and we're an HTML

      // editor (which is global for the document) try to use the last

      // focused selection instead.

      return nsCopySupport::GetSelectionForCopy(GetDocument());

    }

    return do_AddRef(&SelectionRef());

  }();



  const bool clipboardEventCanceled = !nsCopySupport::FireClipboardEvent(

      aEventMessage, aClipboardType, presShell, sel, aActionTaken);

  bool actionTaken = false;

  const bool doDefault = nsCopySupport::FireClipboardEvent(

      aEventMessage, aClipboardType, presShell, sel, &actionTaken);

  NotifyOfDispatchingClipboardEvent();



  // If the event handler caused the editor to be destroyed, return false.

  // Otherwise return true if the event was not cancelled.

  return !clipboardEventCanceled && !mDidPreDestroy;

  if (NS_WARN_IF(Destroyed())) {

    return Err(NS_ERROR_EDITOR_DESTROYED);

  }



  if (doDefault) {

    MOZ_ASSERT(actionTaken);

    return ClipboardEventResult::DoDefault;

  }

  // If we handle a "paste" and nsCopySupport::FireClipboardEvent sets

  // actionTaken to "false" means that it's an error.  Otherwise, the "paste"

  // event is just canceled.

  if (aEventMessage == ePaste) {

    return actionTaken ? ClipboardEventResult::DefaultPreventedOfPaste

                       : ClipboardEventResult::IgnoredOrError;

  }

  // If we handle a "copy", actionTaken is set to true only when

  // nsCopySupport::FireClipboardEvent does not meet an error.

  // If we handle a "cut", actionTaken is set to true only when

  // nsCopySupport::FireClipboardEvent does not meet an error and

  // - the selection is collapsed in editable elements when the event is not

  //   canceled.

  // - the event is canceled but update the clipboard with the dataTransfer

  //   of the event.

  return actionTaken ? ClipboardEventResult::CopyOrCutHandled

                     : ClipboardEventResult::IgnoredOrError;

}



NS_IMETHODIMP EditorBase::Cut() {
@@ -1621,10 +1651,26 @@ nsresult EditorBase::CutAsAction(nsIPrincipal* aPrincipal) { 
    return NS_ERROR_NOT_INITIALIZED;

  }



  bool actionTaken = false;

  if (!FireClipboardEvent(eCut, nsIClipboard::kGlobalClipboard, &actionTaken)) {

    return EditorBase::ToGenericNSResult(

        actionTaken ? NS_OK : NS_ERROR_EDITOR_ACTION_CANCELED);

  {

    Result<ClipboardEventResult, nsresult> ret =

        DispatchClipboardEventAndUpdateClipboard(

            eCut, nsIClipboard::kGlobalClipboard);

    if (MOZ_UNLIKELY(ret.isErr())) {

      NS_WARNING(

          "EditorBase::DispatchClipboardEventAndUpdateClipboard(eCut, "

          "nsIClipboard::kGlobalClipboard) failed");

      return EditorBase::ToGenericNSResult(ret.unwrapErr());

    }

    switch (ret.unwrap()) {

      case ClipboardEventResult::DoDefault:

        break;

      case ClipboardEventResult::CopyOrCutHandled:

        return NS_OK;

      case ClipboardEventResult::IgnoredOrError:

        return EditorBase::ToGenericNSResult(NS_ERROR_EDITOR_ACTION_CANCELED);

      case ClipboardEventResult::DefaultPreventedOfPaste:

        MOZ_ASSERT_UNREACHABLE("Invalid result for eCut");

    }

  }



  // Dispatch "beforeinput" event after dispatching "cut" event.
@@ -1678,11 +1724,25 @@ NS_IMETHODIMP EditorBase::Copy() { 
    return NS_ERROR_NOT_INITIALIZED;

  }



  bool actionTaken = false;

  FireClipboardEvent(eCopy, nsIClipboard::kGlobalClipboard, &actionTaken);



  return EditorBase::ToGenericNSResult(

      actionTaken ? NS_OK : NS_ERROR_EDITOR_ACTION_CANCELED);

  Result<ClipboardEventResult, nsresult> ret =

      DispatchClipboardEventAndUpdateClipboard(eCopy,

                                               nsIClipboard::kGlobalClipboard);

  if (MOZ_UNLIKELY(ret.isErr())) {

    NS_WARNING(

        "EditorBase::DispatchClipboardEventAndUpdateClipboard(eCopy, "

        "nsIClipboard::kGlobalClipboard) failed");

    return EditorBase::ToGenericNSResult(ret.unwrapErr());

  }

  switch (ret.unwrap()) {

    case ClipboardEventResult::DoDefault:

    case ClipboardEventResult::CopyOrCutHandled:

      return NS_OK;

    case ClipboardEventResult::IgnoredOrError:

      return EditorBase::ToGenericNSResult(NS_ERROR_EDITOR_ACTION_CANCELED);

    case ClipboardEventResult::DefaultPreventedOfPaste:

      MOZ_ASSERT_UNREACHABLE("Invalid result for eCopy");

  }

  return NS_ERROR_UNEXPECTED;

}



NS_IMETHODIMP EditorBase::CanCopy(bool* aCanCopy) {

editor/libeditor/EditorBase.h

+22 −7
Original line number Diff line number Diff line
@@ -2619,18 +2619,33 @@ class EditorBase : public nsIEditor, 
      nsAtom* aCommand, EventMessage aEventMessage) const;



  /**

   * FireClipboardEvent() may dispatch a clipboard event.

   * DispatchClipboardEventAndUpdateClipboard() may dispatch a clipboard event

   * and update clipboard if aEventMessage is eCopy or eCut.

   *

   * @param aEventMessage       The event message which may be set to the

   *                            dispatching event.

   * @param aClipboardType      Working with global clipboard or selection.

   * @param aActionTaken        [optional][out] If set to non-nullptr, will be

   *                            set to true if the action for the event is

   *                            handled or prevented default.

   * @return                    false if dispatching event is canceled.

   */

  bool FireClipboardEvent(EventMessage aEventMessage, int32_t aClipboardType,

                          bool* aActionTaken = nullptr);

  enum class ClipboardEventResult {

    // We have met an error in nsCopySupport::FireClipboardEvent,

    // or, default of dispatched event is NOT prevented, the event is "cut"

    // and the event target is not editable.

    IgnoredOrError,

    // A "paste" event is dispatched and prevented its default.

    DefaultPreventedOfPaste,

    // Default of a "copy" or "cut" event is prevented but the clipboard is

    // updated unless the dataTransfer of the event is cleared by the listener.

    // Or, default of the event is NOT prevented but selection is collapsed

    // when the event target is editable or the event is "copy".

    CopyOrCutHandled,

    // A clipboard event is maybe dispatched and not canceled by the web app.

    // In this case, the clipboard has been updated if aEventMessage is eCopy

    // or eCut.

    DoDefault,

  };

  [[nodiscard]] MOZ_CAN_RUN_SCRIPT Result<ClipboardEventResult, nsresult>

  DispatchClipboardEventAndUpdateClipboard(EventMessage aEventMessage,

                                           int32_t aClipboardType);



 private:

  nsCOMPtr<nsISelectionController> mSelectionController;

editor/libeditor/HTMLEditorDataTransfer.cpp

+71 −9
Original line number Diff line number Diff line
@@ -4,7 +4,6 @@ 
 * License, v. 2.0. If a copy of the MPL was not distributed with this

 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */



#include "ErrorList.h"

#include "HTMLEditor.h"



#include <string.h>
@@ -19,6 +18,7 @@ 
#include "SelectionState.h"

#include "WSRunObject.h"



#include "ErrorList.h"

#include "mozilla/dom/Comment.h"

#include "mozilla/dom/DataTransfer.h"

#include "mozilla/dom/Document.h"
@@ -2275,8 +2275,22 @@ nsresult HTMLEditor::PasteAsAction(int32_t aClipboardType, 
  }



  if (aDispatchPasteEvent) {

    if (!FireClipboardEvent(ePaste, aClipboardType)) {

    Result<ClipboardEventResult, nsresult> ret =

        DispatchClipboardEventAndUpdateClipboard(ePaste, aClipboardType);

    if (MOZ_UNLIKELY(ret.isErr())) {

      NS_WARNING(

          "EditorBase::DispatchClipboardEventAndUpdateClipboard(ePaste) "

          "failed");

      return EditorBase::ToGenericNSResult(ret.unwrapErr());

    }

    switch (ret.inspect()) {

      case ClipboardEventResult::DoDefault:

        break;

      case ClipboardEventResult::DefaultPreventedOfPaste:

      case ClipboardEventResult::IgnoredOrError:

        return EditorBase::ToGenericNSResult(NS_ERROR_EDITOR_ACTION_CANCELED);

      case ClipboardEventResult::CopyOrCutHandled:

        MOZ_ASSERT_UNREACHABLE("Invalid result for ePaste");

    }

  } else {

    // The caller must already have dispatched a "paste" event.
@@ -2428,8 +2442,25 @@ nsresult HTMLEditor::PasteTransferableAsAction(nsITransferable* aTransferable, 
  // Use an invalid value for the clipboard type as data comes from

  // aTransferable and we don't currently implement a way to put that in the

  // data transfer yet.

  if (!FireClipboardEvent(ePaste, nsIClipboard::kGlobalClipboard)) {

  {

    Result<ClipboardEventResult, nsresult> ret =

        DispatchClipboardEventAndUpdateClipboard(

            ePaste, nsIClipboard::kGlobalClipboard);

    if (MOZ_UNLIKELY(ret.isErr())) {

      NS_WARNING(

          "EditorBase::DispatchClipboardEventAndUpdateClipboard(ePaste, "

          "nsIClipboard::kGlobalClipboard) failed");

      return EditorBase::ToGenericNSResult(ret.unwrapErr());

    }

    switch (ret.inspect()) {

      case ClipboardEventResult::DoDefault:

        break;

      case ClipboardEventResult::DefaultPreventedOfPaste:

      case ClipboardEventResult::IgnoredOrError:

        return EditorBase::ToGenericNSResult(NS_ERROR_EDITOR_ACTION_CANCELED);

      case ClipboardEventResult::CopyOrCutHandled:

        MOZ_ASSERT_UNREACHABLE("Invalid result for ePaste");

    }

  }



  // Dispatch "beforeinput" event after "paste" event.
@@ -2476,8 +2507,25 @@ nsresult HTMLEditor::PasteNoFormattingAsAction(int32_t aSelectionType, 
  editActionData.InitializeDataTransferWithClipboard(

      SettingDataTransfer::eWithoutFormat, aSelectionType);



  if (!FireClipboardEvent(ePasteNoFormatting, aSelectionType)) {

  {

    Result<ClipboardEventResult, nsresult> ret =

        DispatchClipboardEventAndUpdateClipboard(ePasteNoFormatting,

                                                 aSelectionType);

    if (MOZ_UNLIKELY(ret.isErr())) {

      NS_WARNING(

          "EditorBase::DispatchClipboardEventAndUpdateClipboard("

          "ePasteNoFormatting) failed");

      return EditorBase::ToGenericNSResult(ret.unwrapErr());

    }

    switch (ret.inspect()) {

      case ClipboardEventResult::DoDefault:

        break;

      case ClipboardEventResult::DefaultPreventedOfPaste:

      case ClipboardEventResult::IgnoredOrError:

        return EditorBase::ToGenericNSResult(NS_ERROR_EDITOR_ACTION_CANCELED);

      case ClipboardEventResult::CopyOrCutHandled:

        MOZ_ASSERT_UNREACHABLE("Invalid result for ePaste");

    }

  }



  // Dispatch "beforeinput" event after "paste" event.  And perhaps, before
@@ -2645,8 +2693,22 @@ nsresult HTMLEditor::PasteAsQuotationAsAction(int32_t aClipboardType, 
  }



  if (aDispatchPasteEvent) {

    if (!FireClipboardEvent(ePaste, aClipboardType)) {

    Result<ClipboardEventResult, nsresult> ret =

        DispatchClipboardEventAndUpdateClipboard(ePaste, aClipboardType);

    if (MOZ_UNLIKELY(ret.isErr())) {

      NS_WARNING(

          "EditorBase::DispatchClipboardEventAndUpdateClipboard(ePaste) "

          "failed");

      return EditorBase::ToGenericNSResult(ret.unwrapErr());

    }

    switch (ret.inspect()) {

      case ClipboardEventResult::DoDefault:

        break;

      case ClipboardEventResult::DefaultPreventedOfPaste:

      case ClipboardEventResult::IgnoredOrError:

        return EditorBase::ToGenericNSResult(NS_ERROR_EDITOR_ACTION_CANCELED);

      case ClipboardEventResult::CopyOrCutHandled:

        MOZ_ASSERT_UNREACHABLE("Invalid result for ePaste");

    }

  } else {

    // The caller must already have dispatched a "paste" event.

editor/libeditor/TextEditorDataTransfer.cpp

+37 −7
Original line number Diff line number Diff line
@@ -170,8 +170,22 @@ nsresult TextEditor::PasteAsAction(int32_t aClipboardType, 
  }



  if (aDispatchPasteEvent) {

    if (!FireClipboardEvent(ePaste, aClipboardType)) {

    Result<ClipboardEventResult, nsresult> ret =

        DispatchClipboardEventAndUpdateClipboard(ePaste, aClipboardType);

    if (MOZ_UNLIKELY(ret.isErr())) {

      NS_WARNING(

          "EditorBase::DispatchClipboardEventAndUpdateClipboard(ePaste) "

          "failed");

      return EditorBase::ToGenericNSResult(ret.unwrapErr());

    }

    switch (ret.inspect()) {

      case ClipboardEventResult::DoDefault:

        break;

      case ClipboardEventResult::DefaultPreventedOfPaste:

      case ClipboardEventResult::IgnoredOrError:

        return EditorBase::ToGenericNSResult(NS_ERROR_EDITOR_ACTION_CANCELED);

      case ClipboardEventResult::CopyOrCutHandled:

        MOZ_ASSERT_UNREACHABLE("Invalid result for ePaste");

    }

  } else {

    // The caller must already have dispatched a "paste" event.
@@ -235,11 +249,27 @@ nsresult TextEditor::PasteTransferableAsAction(nsITransferable* aTransferable, 
    return NS_ERROR_NOT_INITIALIZED;

  }



  {

    // Use an invalid value for the clipboard type as data comes from

    // aTransferable and we don't currently implement a way to put that in the

    // data transfer yet.

  if (!FireClipboardEvent(ePaste, -1)) {

    Result<ClipboardEventResult, nsresult> ret =

        DispatchClipboardEventAndUpdateClipboard(ePaste, -1);

    if (MOZ_UNLIKELY(ret.isErr())) {

      NS_WARNING(

          "EditorBase::DispatchClipboardEventAndUpdateClipboard(ePaste, -1) "

          "failed");

      return EditorBase::ToGenericNSResult(ret.unwrapErr());

    }

    switch (ret.inspect()) {

      case ClipboardEventResult::DoDefault:

        break;

      case ClipboardEventResult::DefaultPreventedOfPaste:

      case ClipboardEventResult::IgnoredOrError:

        return EditorBase::ToGenericNSResult(NS_ERROR_EDITOR_ACTION_CANCELED);

      case ClipboardEventResult::CopyOrCutHandled:

        MOZ_ASSERT_UNREACHABLE("Invalid result for ePaste");

    }

  }



  if (!IsModifiable()) {