1 files changed, 908 insertions, 0 deletions
diff --git a/dom/base/nsCopySupport.cpp b/dom/base/nsCopySupport.cpp
new file mode 100644
index 0000000000..de58a735b2
--- /dev/null
+++ b/dom/base/nsCopySupport.cpp
@@ -0,0 +1,908 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * 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 "nsCopySupport.h"
+#include "nsIDocumentEncoder.h"
+#include "nsISupports.h"
+#include "nsIContent.h"
+#include "nsIClipboard.h"
+#include "nsIFormControl.h"
+#include "nsWidgetsCID.h"
+#include "nsXPCOM.h"
+#include "nsISupportsPrimitives.h"
+#include "nsRange.h"
+#include "imgIContainer.h"
+#include "imgIRequest.h"
+#include "nsComponentManagerUtils.h"
+#include "nsFocusManager.h"
+#include "nsFrameSelection.h"
+#include "nsServiceManagerUtils.h"
+#include "mozilla/ScopeExit.h"
+#include "mozilla/dom/DataTransfer.h"
+
+#include "nsIDocShell.h"
+#include "nsIContentViewerEdit.h"
+#include "nsISelectionController.h"
+
+#include "nsPIDOMWindow.h"
+#include "mozilla/dom/Document.h"
+#include "nsHTMLDocument.h"
+#include "nsGkAtoms.h"
+#include "nsIFrame.h"
+
+// image copy stuff
+#include "nsIImageLoadingContent.h"
+#include "nsIInterfaceRequestorUtils.h"
+#include "nsContentUtils.h"
+#include "nsContentCID.h"
+
+#ifdef XP_WIN
+#  include "nsCExternalHandlerService.h"
+#  include "nsEscape.h"
+#  include "nsIMIMEInfo.h"
+#  include "nsIMIMEService.h"
+#  include "nsIURIMutator.h"
+#  include "nsIURL.h"
+#  include "nsReadableUtils.h"
+#  include "nsXULAppAPI.h"
+#endif
+
+#include "mozilla/ContentEvents.h"
+#include "mozilla/EventDispatcher.h"
+#include "mozilla/Preferences.h"
+#include "mozilla/PresShell.h"
+#include "mozilla/TextEditor.h"
+#include "mozilla/IntegerRange.h"
+#include "mozilla/dom/Element.h"
+#include "mozilla/dom/HTMLInputElement.h"
+#include "mozilla/dom/Selection.h"
+
+using namespace mozilla;
+using namespace mozilla::dom;
+
+static NS_DEFINE_CID(kCClipboardCID, NS_CLIPBOARD_CID);
+static NS_DEFINE_CID(kCTransferableCID, NS_TRANSFERABLE_CID);
+static NS_DEFINE_CID(kHTMLConverterCID, NS_HTMLFORMATCONVERTER_CID);
+
+// copy string data onto the transferable
+static nsresult AppendString(nsITransferable* aTransferable,
+                             const nsAString& aString, const char* aFlavor);
+
+// copy HTML node data
+static nsresult AppendDOMNode(nsITransferable* aTransferable,
+                              nsINode* aDOMNode);
+
+#ifdef XP_WIN
+// copy image as file promise onto the transferable
+static nsresult AppendImagePromise(nsITransferable* aTransferable,
+                                   imgIRequest* aImgRequest,
+                                   nsIImageLoadingContent* aImageElement);
+#endif
+
+static nsresult EncodeForTextUnicode(nsIDocumentEncoder& aEncoder,
+                                     Document& aDocument, Selection* aSelection,
+                                     uint32_t aAdditionalEncoderFlags,
+                                     bool& aEncodedAsTextHTMLResult,
+                                     nsAutoString& aSerializationResult) {
+  // note that we assign text/unicode as mime type, but in fact
+  // nsHTMLCopyEncoder ignore it and use text/html or text/plain depending where
+  // the selection is. if it is a selection into input/textarea element or in a
+  // html content with pre-wrap style : text/plain. Otherwise text/html. see
+  // nsHTMLCopyEncoder::SetSelection
+  nsAutoString mimeType;
+  mimeType.AssignLiteral("text/unicode");
+
+  // Do the first and potentially trial encoding as preformatted and raw.
+  uint32_t flags = aAdditionalEncoderFlags |
+                   nsIDocumentEncoder::OutputPreformatted |
+                   nsIDocumentEncoder::OutputRaw |
+                   nsIDocumentEncoder::OutputForPlainTextClipboardCopy |
+                   nsIDocumentEncoder::OutputPersistNBSP;
+
+  nsresult rv = aEncoder.Init(&aDocument, mimeType, flags);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  rv = aEncoder.SetSelection(aSelection);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  // SetSelection set the mime type to text/plain if the selection is inside a
+  // text widget.
+  rv = aEncoder.GetMimeType(mimeType);
+  NS_ENSURE_SUCCESS(rv, rv);
+  bool selForcedTextPlain = mimeType.EqualsLiteral(kTextMime);
+
+  nsAutoString buf;
+  rv = aEncoder.EncodeToString(buf);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  rv = aEncoder.GetMimeType(mimeType);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  // The mime type is ultimately text/html if the encoder successfully encoded
+  // the selection as text/html.
+  aEncodedAsTextHTMLResult = mimeType.EqualsLiteral(kHTMLMime);
+
+  if (selForcedTextPlain) {
+    // Nothing to do.  buf contains the final, preformatted, raw text/plain.
+    aSerializationResult.Assign(buf);
+  } else {
+    // Redo the encoding, but this time use pretty printing.
+    flags =
+        nsIDocumentEncoder::OutputSelectionOnly |
+        nsIDocumentEncoder::OutputAbsoluteLinks |
+        nsIDocumentEncoder::SkipInvisibleContent |
+        nsIDocumentEncoder::OutputDropInvisibleBreak |
+        (aAdditionalEncoderFlags & (nsIDocumentEncoder::OutputNoScriptContent |
+                                    nsIDocumentEncoder::OutputRubyAnnotation));
+
+    mimeType.AssignLiteral(kTextMime);
+    rv = aEncoder.Init(&aDocument, mimeType, flags);
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    rv = aEncoder.SetSelection(aSelection);
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    rv = aEncoder.EncodeToString(aSerializationResult);
+    NS_ENSURE_SUCCESS(rv, rv);
+  }
+
+  return rv;
+}
+
+static nsresult EncodeAsTextHTMLWithContext(
+    nsIDocumentEncoder& aEncoder, Document& aDocument, Selection* aSelection,
+    uint32_t aEncoderFlags, nsAutoString& aTextHTMLEncodingResult,
+    nsAutoString& aHTMLParentsBufResult, nsAutoString& aHTMLInfoBufResult) {
+  nsAutoString mimeType;
+  mimeType.AssignLiteral(kHTMLMime);
+  nsresult rv = aEncoder.Init(&aDocument, mimeType, aEncoderFlags);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  rv = aEncoder.SetSelection(aSelection);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  rv = aEncoder.EncodeToStringWithContext(
+      aHTMLParentsBufResult, aHTMLInfoBufResult, aTextHTMLEncodingResult);
+  NS_ENSURE_SUCCESS(rv, rv);
+  return rv;
+}
+
+struct EncodedDocumentWithContext {
+  // When determining `mSerializationForTextUnicode`, `text/unicode` is passed
+  // as mime type to the encoder. It uses this as a switch to decide whether to
+  // encode the document as `text/html` or `text/plain`. It  is `true` iff
+  // `text/html` was used.
+  bool mUnicodeEncodingIsTextHTML = false;
+
+  // The serialized document when encoding the document with `text/unicode`. See
+  // comment of `mUnicodeEncodingIsTextHTML`.
+  nsAutoString mSerializationForTextUnicode;
+
+  // When `mUnicodeEncodingIsTextHTML` is true, this is the serialized document
+  // using `text/html`. Its value may differ from `mSerializationForTextHTML`,
+  // because different flags were passed to the encoder.
+  nsAutoString mSerializationForTextHTML;
+
+  // When `mUnicodeEncodingIsTextHTML` is true, this contains the serialized
+  // ancestor elements.
+  nsAutoString mHTMLContextBuffer;
+
+  // When `mUnicodeEncodingIsTextHTML` is true, this contains numbers
+  // identifying where in the context the serialization came from.
+  nsAutoString mHTMLInfoBuffer;
+};
+
+/**
+ * @param aSelection Can be nullptr.
+ * @param aAdditionalEncoderFlags nsIDocumentEncoder flags.
+ */
+static nsresult EncodeDocumentWithContext(
+    Document& aDocument, Selection* aSelection,
+    uint32_t aAdditionalEncoderFlags,
+    EncodedDocumentWithContext& aEncodedDocumentWithContext) {
+  nsCOMPtr<nsIDocumentEncoder> docEncoder = do_createHTMLCopyEncoder();
+
+  bool unicodeEncodingIsTextHTML{false};
+  nsAutoString serializationForTextUnicode;
+  nsresult rv = EncodeForTextUnicode(
+      *docEncoder, aDocument, aSelection, aAdditionalEncoderFlags,
+      unicodeEncodingIsTextHTML, serializationForTextUnicode);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  nsAutoString serializationForTextHTML;
+  nsAutoString htmlContextBuffer;
+  nsAutoString htmlInfoBuffer;
+  if (unicodeEncodingIsTextHTML) {
+    // Redo the encoding, but this time use the passed-in flags.
+    // Don't allow wrapping of CJK strings.
+    rv = EncodeAsTextHTMLWithContext(
+        *docEncoder, aDocument, aSelection,
+        aAdditionalEncoderFlags |
+            nsIDocumentEncoder::OutputDisallowLineBreaking,
+        serializationForTextHTML, htmlContextBuffer, htmlInfoBuffer);
+    NS_ENSURE_SUCCESS(rv, rv);
+  }
+
+  aEncodedDocumentWithContext = {
+      unicodeEncodingIsTextHTML, std::move(serializationForTextUnicode),
+      std::move(serializationForTextHTML), std::move(htmlContextBuffer),
+      std::move(htmlInfoBuffer)};
+
+  return rv;
+}
+
+static nsresult CreateTransferable(
+    const EncodedDocumentWithContext& aEncodedDocumentWithContext,
+    Document& aDocument, nsCOMPtr<nsITransferable>& aTransferable) {
+  nsresult rv = NS_OK;
+
+  aTransferable = do_CreateInstance(kCTransferableCID);
+  NS_ENSURE_TRUE(aTransferable, NS_ERROR_NULL_POINTER);
+
+  aTransferable->Init(aDocument.GetLoadContext());
+  if (aEncodedDocumentWithContext.mUnicodeEncodingIsTextHTML) {
+    // Set up a format converter so that clipboard flavor queries work.
+    // This converter isn't really used for conversions.
+    nsCOMPtr<nsIFormatConverter> htmlConverter =
+        do_CreateInstance(kHTMLConverterCID);
+    aTransferable->SetConverter(htmlConverter);
+
+    if (!aEncodedDocumentWithContext.mSerializationForTextHTML.IsEmpty()) {
+      // Add the html DataFlavor to the transferable
+      rv = AppendString(aTransferable,
+                        aEncodedDocumentWithContext.mSerializationForTextHTML,
+                        kHTMLMime);
+      NS_ENSURE_SUCCESS(rv, rv);
+    }
+
+    // Add the htmlcontext DataFlavor to the transferable. Even if the context
+    // buffer is empty, this flavor should be attached to the transferable.
+    rv = AppendString(aTransferable,
+                      aEncodedDocumentWithContext.mHTMLContextBuffer,
+                      kHTMLContext);
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    if (!aEncodedDocumentWithContext.mHTMLInfoBuffer.IsEmpty()) {
+      // Add the htmlinfo DataFlavor to the transferable
+      rv = AppendString(aTransferable,
+                        aEncodedDocumentWithContext.mHTMLInfoBuffer, kHTMLInfo);
+      NS_ENSURE_SUCCESS(rv, rv);
+    }
+
+    if (!aEncodedDocumentWithContext.mSerializationForTextUnicode.IsEmpty()) {
+      // unicode text
+      // Add the plain text DataFlavor to the transferable
+      // If we didn't have this, then nsDataObj::GetData matches
+      // text/plain against the kURLMime flavour which is not desirable
+      // (eg. when pasting into Notepad)
+      rv = AppendString(
+          aTransferable,
+          aEncodedDocumentWithContext.mSerializationForTextUnicode, kTextMime);
+      NS_ENSURE_SUCCESS(rv, rv);
+    }
+
+    // Try and get source URI of the items that are being dragged
+    nsIURI* uri = aDocument.GetDocumentURI();
+    if (uri) {
+      nsAutoCString spec;
+      nsresult rv = uri->GetSpec(spec);
+      NS_ENSURE_SUCCESS(rv, rv);
+      if (!spec.IsEmpty()) {
+        nsAutoString shortcut;
+        AppendUTF8toUTF16(spec, shortcut);
+
+        // Add the URL DataFlavor to the transferable. Don't use kURLMime,
+        // as it will cause an unnecessary UniformResourceLocator to be
+        // added which confuses some apps eg. Outlook 2000 - (See Bug
+        // 315370). Don't use kURLDataMime, as it will cause a bogus 'url '
+        // flavor to show up on the Mac clipboard, confusing other apps,
+        // like Terminal (see bug 336012).
+        rv = AppendString(aTransferable, shortcut, kURLPrivateMime);
+        NS_ENSURE_SUCCESS(rv, rv);
+      }
+    }
+  } else {
+    if (!aEncodedDocumentWithContext.mSerializationForTextUnicode.IsEmpty()) {
+      // Add the unicode DataFlavor to the transferable
+      rv = AppendString(
+          aTransferable,
+          aEncodedDocumentWithContext.mSerializationForTextUnicode, kTextMime);
+      NS_ENSURE_SUCCESS(rv, rv);
+    }
+  }
+
+  return rv;
+}
+
+static nsresult PutToClipboard(
+    const EncodedDocumentWithContext& aEncodedDocumentWithContext,
+    int16_t aClipboardID, Document& aDocument) {
+  nsresult rv;
+  nsCOMPtr<nsIClipboard> clipboard = do_GetService(kCClipboardCID, &rv);
+  NS_ENSURE_SUCCESS(rv, rv);
+  NS_ENSURE_TRUE(clipboard, NS_ERROR_NULL_POINTER);
+
+  nsCOMPtr<nsITransferable> transferable;
+  rv = CreateTransferable(aEncodedDocumentWithContext, aDocument, transferable);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  rv = clipboard->SetData(transferable, nullptr, aClipboardID);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  return rv;
+}
+
+nsresult nsCopySupport::EncodeDocumentWithContextAndPutToClipboard(
+    Selection* aSel, Document* aDoc, int16_t aClipboardID,
+    bool aWithRubyAnnotation) {
+  NS_ENSURE_TRUE(aDoc, NS_ERROR_NULL_POINTER);
+
+  uint32_t additionalFlags = nsIDocumentEncoder::SkipInvisibleContent;
+  if (aWithRubyAnnotation) {
+    additionalFlags |= nsIDocumentEncoder::OutputRubyAnnotation;
+  }
+
+  EncodedDocumentWithContext encodedDocumentWithContext;
+  nsresult rv = EncodeDocumentWithContext(*aDoc, aSel, additionalFlags,
+                                          encodedDocumentWithContext);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  rv = PutToClipboard(encodedDocumentWithContext, aClipboardID, *aDoc);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  return rv;
+}
+
+nsresult nsCopySupport::ClearSelectionCache() {
+  nsresult rv;
+  nsCOMPtr<nsIClipboard> clipboard = do_GetService(kCClipboardCID, &rv);
+  clipboard->EmptyClipboard(nsIClipboard::kSelectionCache);
+  return rv;
+}
+
+/**
+ * @param aAdditionalEncoderFlags flags of `nsIDocumentEncoder`.
+ * @param aTransferable Needs to be not `nullptr`.
+ */
+static nsresult EncodeDocumentWithContextAndCreateTransferable(
+    Document& aDocument, Selection* aSelection,
+    uint32_t aAdditionalEncoderFlags, nsITransferable** aTransferable) {
+  NS_ENSURE_TRUE(aTransferable, NS_ERROR_NULL_POINTER);
+
+  // Clear the output parameter for the transferable.
+  *aTransferable = nullptr;
+
+  EncodedDocumentWithContext encodedDocumentWithContext;
+  nsresult rv =
+      EncodeDocumentWithContext(aDocument, aSelection, aAdditionalEncoderFlags,
+                                encodedDocumentWithContext);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  nsCOMPtr<nsITransferable> transferable;
+  rv = CreateTransferable(encodedDocumentWithContext, aDocument, transferable);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  transferable.swap(*aTransferable);
+  return rv;
+}
+
+nsresult nsCopySupport::GetTransferableForSelection(
+    Selection* aSel, Document* aDoc, nsITransferable** aTransferable) {
+  NS_ENSURE_TRUE(aDoc, NS_ERROR_NULL_POINTER);
+  NS_ENSURE_TRUE(aTransferable, NS_ERROR_NULL_POINTER);
+
+  const uint32_t additionalFlags = nsIDocumentEncoder::SkipInvisibleContent;
+  return EncodeDocumentWithContextAndCreateTransferable(
+      *aDoc, aSel, additionalFlags, aTransferable);
+}
+
+nsresult nsCopySupport::GetTransferableForNode(
+    nsINode* aNode, Document* aDoc, nsITransferable** aTransferable) {
+  NS_ENSURE_TRUE(aNode, NS_ERROR_NULL_POINTER);
+  NS_ENSURE_TRUE(aDoc, NS_ERROR_NULL_POINTER);
+  NS_ENSURE_TRUE(aTransferable, NS_ERROR_NULL_POINTER);
+
+  // Make a temporary selection with aNode in a single range.
+  // XXX We should try to get rid of the Selection object here.
+  // XXX bug 1245883
+  RefPtr<Selection> selection = new Selection(SelectionType::eNormal, nullptr);
+  RefPtr<nsRange> range = nsRange::Create(aNode);
+  ErrorResult result;
+  range->SelectNode(*aNode, result);
+  if (NS_WARN_IF(result.Failed())) {
+    return result.StealNSResult();
+  }
+  selection->AddRangeAndSelectFramesAndNotifyListenersInternal(*range, aDoc,
+                                                               result);
+  if (NS_WARN_IF(result.Failed())) {
+    return result.StealNSResult();
+  }
+  // It's not the primary selection - so don't skip invisible content.
+  uint32_t additionalFlags = 0;
+  return EncodeDocumentWithContextAndCreateTransferable(
+      *aDoc, selection, additionalFlags, aTransferable);
+}
+
+nsresult nsCopySupport::GetContents(const nsACString& aMimeType,
+                                    uint32_t aFlags, Selection* aSel,
+                                    Document* aDoc, nsAString& outdata) {
+  nsCOMPtr<nsIDocumentEncoder> docEncoder =
+      do_createDocumentEncoder(PromiseFlatCString(aMimeType).get());
+  NS_ENSURE_TRUE(docEncoder, NS_ERROR_FAILURE);
+
+  uint32_t flags = aFlags | nsIDocumentEncoder::SkipInvisibleContent;
+
+  if (aMimeType.EqualsLiteral("text/plain"))
+    flags |= nsIDocumentEncoder::OutputPreformatted;
+
+  NS_ConvertASCIItoUTF16 unicodeMimeType(aMimeType);
+
+  nsresult rv = docEncoder->Init(aDoc, unicodeMimeType, flags);
+  if (NS_FAILED(rv)) return rv;
+
+  if (aSel) {
+    rv = docEncoder->SetSelection(aSel);
+    if (NS_FAILED(rv)) return rv;
+  }
+
+  // encode the selection
+  return docEncoder->EncodeToString(outdata);
+}
+
+nsresult nsCopySupport::ImageCopy(nsIImageLoadingContent* aImageElement,
+                                  nsILoadContext* aLoadContext,
+                                  int32_t aCopyFlags) {
+  nsresult rv;
+
+  // create a transferable for putting data on the Clipboard
+  nsCOMPtr<nsITransferable> trans(do_CreateInstance(kCTransferableCID, &rv));
+  NS_ENSURE_SUCCESS(rv, rv);
+  trans->Init(aLoadContext);
+
+  if (aCopyFlags & nsIContentViewerEdit::COPY_IMAGE_TEXT) {
+    // get the location from the element
+    nsCOMPtr<nsIURI> uri;
+    rv = aImageElement->GetCurrentURI(getter_AddRefs(uri));
+    NS_ENSURE_SUCCESS(rv, rv);
+    NS_ENSURE_TRUE(uri, NS_ERROR_FAILURE);
+
+    nsAutoCString location;
+    rv = uri->GetSpec(location);
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    // append the string to the transferable
+    rv = AppendString(trans, NS_ConvertUTF8toUTF16(location), kTextMime);
+    NS_ENSURE_SUCCESS(rv, rv);
+  }
+
+  if (aCopyFlags & nsIContentViewerEdit::COPY_IMAGE_HTML) {
+    // append HTML data to the transferable
+    nsCOMPtr<nsINode> node(do_QueryInterface(aImageElement, &rv));
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    rv = AppendDOMNode(trans, node);
+    NS_ENSURE_SUCCESS(rv, rv);
+  }
+
+  if (aCopyFlags & nsIContentViewerEdit::COPY_IMAGE_DATA) {
+    // get the image data and its request from the element
+    nsCOMPtr<imgIRequest> imgRequest;
+    nsCOMPtr<imgIContainer> image = nsContentUtils::GetImageFromContent(
+        aImageElement, getter_AddRefs(imgRequest));
+    NS_ENSURE_TRUE(image, NS_ERROR_FAILURE);
+
+    if (imgRequest) {
+      // Remember the referrer used for this image request.
+      nsCOMPtr<nsIReferrerInfo> referrerInfo;
+      imgRequest->GetReferrerInfo(getter_AddRefs(referrerInfo));
+      trans->SetReferrerInfo(referrerInfo);
+    }
+
+#ifdef XP_WIN
+    rv = AppendImagePromise(trans, imgRequest, aImageElement);
+    NS_ENSURE_SUCCESS(rv, rv);
+#endif
+
+    // copy the image data onto the transferable
+    rv = trans->SetTransferData(kNativeImageMime, image);
+    NS_ENSURE_SUCCESS(rv, rv);
+  }
+
+  // get clipboard
+  nsCOMPtr<nsIClipboard> clipboard(do_GetService(kCClipboardCID, &rv));
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  // check whether the system supports the selection clipboard or not.
+  if (clipboard->IsClipboardTypeSupported(nsIClipboard::kSelectionClipboard)) {
+    // put the transferable on the clipboard
+    rv = clipboard->SetData(trans, nullptr, nsIClipboard::kSelectionClipboard);
+    NS_ENSURE_SUCCESS(rv, rv);
+  }
+
+  return clipboard->SetData(trans, nullptr, nsIClipboard::kGlobalClipboard);
+}
+
+static nsresult AppendString(nsITransferable* aTransferable,
+                             const nsAString& aString, const char* aFlavor) {
+  nsresult rv;
+
+  nsCOMPtr<nsISupportsString> data(
+      do_CreateInstance(NS_SUPPORTS_STRING_CONTRACTID, &rv));
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  rv = data->SetData(aString);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  rv = aTransferable->AddDataFlavor(aFlavor);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  return aTransferable->SetTransferData(aFlavor, data);
+}
+
+static nsresult AppendDOMNode(nsITransferable* aTransferable,
+                              nsINode* aDOMNode) {
+  nsresult rv;
+
+  // serializer
+  nsCOMPtr<nsIDocumentEncoder> docEncoder = do_createHTMLCopyEncoder();
+
+  // get document for the encoder
+  nsCOMPtr<Document> document = aDOMNode->OwnerDoc();
+
+  // Note that XHTML is not counted as HTML here, because we can't copy it
+  // properly (all the copy code for non-plaintext assumes using HTML
+  // serializers and parsers is OK, and those mess up XHTML).
+  NS_ENSURE_TRUE(document->IsHTMLDocument(), NS_OK);
+
+  // init encoder with document and node
+  rv = docEncoder->NativeInit(
+      document, NS_LITERAL_STRING_FROM_CSTRING(kHTMLMime),
+      nsIDocumentEncoder::OutputAbsoluteLinks |
+          nsIDocumentEncoder::OutputEncodeBasicEntities);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  rv = docEncoder->SetNode(aDOMNode);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  // serialize to string
+  nsAutoString html, context, info;
+  rv = docEncoder->EncodeToStringWithContext(context, info, html);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  // copy them to the transferable
+  if (!html.IsEmpty()) {
+    rv = AppendString(aTransferable, html, kHTMLMime);
+    NS_ENSURE_SUCCESS(rv, rv);
+  }
+
+  if (!info.IsEmpty()) {
+    rv = AppendString(aTransferable, info, kHTMLInfo);
+    NS_ENSURE_SUCCESS(rv, rv);
+  }
+
+  // add a special flavor, even if we don't have html context data
+  return AppendString(aTransferable, context, kHTMLContext);
+}
+
+#ifdef XP_WIN
+static nsresult AppendImagePromise(nsITransferable* aTransferable,
+                                   imgIRequest* aImgRequest,
+                                   nsIImageLoadingContent* aImageElement) {
+  nsresult rv;
+
+  NS_ENSURE_TRUE(aImgRequest, NS_OK);
+
+  bool isMultipart;
+  rv = aImgRequest->GetMultipart(&isMultipart);
+  NS_ENSURE_SUCCESS(rv, rv);
+  if (isMultipart) {
+    return NS_OK;
+  }
+
+  nsCOMPtr<nsINode> node = do_QueryInterface(aImageElement, &rv);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  nsCOMPtr<nsIMIMEService> mimeService = do_GetService("@mozilla.org/mime;1");
+  if (NS_WARN_IF(!mimeService)) {
+    return NS_ERROR_FAILURE;
+  }
+
+  nsCOMPtr<nsIURI> imgUri;
+  rv = aImgRequest->GetFinalURI(getter_AddRefs(imgUri));
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  nsAutoCString spec;
+  rv = imgUri->GetSpec(spec);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  // pass out the image source string
+  nsString imageSourceString;
+  CopyUTF8toUTF16(spec, imageSourceString);
+
+  nsCString mimeType;
+  rv = aImgRequest->GetMimeType(getter_Copies(mimeType));
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  nsAutoCString fileName;
+  rv = aImgRequest->GetFileName(fileName);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  nsAutoString validFileName = NS_ConvertUTF8toUTF16(fileName);
+  mimeService->ValidateFileNameForSaving(
+      validFileName, mimeType, nsIMIMEService::VALIDATE_DEFAULT, validFileName);
+
+  rv = AppendString(aTransferable, imageSourceString, kFilePromiseURLMime);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  rv = AppendString(aTransferable, validFileName, kFilePromiseDestFilename);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  aTransferable->SetRequestingPrincipal(node->NodePrincipal());
+  aTransferable->SetCookieJarSettings(node->OwnerDoc()->CookieJarSettings());
+  aTransferable->SetContentPolicyType(nsIContentPolicy::TYPE_INTERNAL_IMAGE);
+
+  // add the dataless file promise flavor
+  return aTransferable->AddDataFlavor(kFilePromiseMime);
+}
+#endif  // XP_WIN
+
+already_AddRefed<Selection> nsCopySupport::GetSelectionForCopy(
+    Document* aDocument) {
+  PresShell* presShell = aDocument->GetPresShell();
+  if (NS_WARN_IF(!presShell)) {
+    return nullptr;
+  }
+
+  RefPtr<nsFrameSelection> frameSel = presShell->GetLastFocusedFrameSelection();
+  if (NS_WARN_IF(!frameSel)) {
+    return nullptr;
+  }
+
+  RefPtr<Selection> sel = frameSel->GetSelection(SelectionType::eNormal);
+  return sel.forget();
+}
+
+bool nsCopySupport::CanCopy(Document* aDocument) {
+  if (!aDocument) {
+    return false;
+  }
+
+  RefPtr<Selection> sel = GetSelectionForCopy(aDocument);
+  return sel && !sel->IsCollapsed();
+}
+
+static bool IsInsideRuby(nsINode* aNode) {
+  for (; aNode; aNode = aNode->GetParent()) {
+    if (aNode->IsHTMLElement(nsGkAtoms::ruby)) {
+      return true;
+    }
+  }
+  return false;
+}
+
+static bool IsSelectionInsideRuby(Selection* aSelection) {
+  uint32_t rangeCount = aSelection->RangeCount();
+  for (auto i : IntegerRange(rangeCount)) {
+    MOZ_ASSERT(aSelection->RangeCount() == rangeCount);
+    const nsRange* range = aSelection->GetRangeAt(i);
+    if (!IsInsideRuby(range->GetClosestCommonInclusiveAncestor())) {
+      return false;
+    }
+  }
+  return true;
+}
+
+static Element* GetElementOrNearestFlattenedTreeParentElement(nsINode* aNode) {
+  if (!aNode->IsContent()) {
+    return nullptr;
+  }
+  for (nsIContent* content = aNode->AsContent(); content;
+       content = content->GetFlattenedTreeParent()) {
+    if (content->IsElement()) {
+      return content->AsElement();
+    }
+  }
+  return nullptr;
+}
+
+bool nsCopySupport::FireClipboardEvent(EventMessage aEventMessage,
+                                       int32_t aClipboardType,
+                                       PresShell* aPresShell,
+                                       Selection* aSelection,
+                                       bool* aActionTaken) {
+  if (aActionTaken) {
+    *aActionTaken = false;
+  }
+
+  EventMessage originalEventMessage = aEventMessage;
+  if (originalEventMessage == ePasteNoFormatting) {
+    originalEventMessage = ePaste;
+  }
+
+  NS_ASSERTION(originalEventMessage == eCut || originalEventMessage == eCopy ||
+                   originalEventMessage == ePaste,
+               "Invalid clipboard event type");
+
+  RefPtr<PresShell> presShell = aPresShell;
+  if (!presShell) {
+    return false;
+  }
+
+  nsCOMPtr<Document> doc = presShell->GetDocument();
+  if (!doc) return false;
+
+  nsCOMPtr<nsPIDOMWindowOuter> piWindow = doc->GetWindow();
+  if (!piWindow) return false;
+
+  // Event target of clipboard events should be an element node which
+  // contains selection start container.
+  RefPtr<Element> targetElement;
+
+  // If a selection was not supplied, try to find it.
+  RefPtr<Selection> sel = aSelection;
+  if (!sel) {
+    sel = GetSelectionForCopy(doc);
+  }
+
+  // Retrieve the event target node from the start of the selection.
+  if (sel) {
+    const nsRange* range = sel->GetRangeAt(0);
+    if (range) {
+      targetElement = GetElementOrNearestFlattenedTreeParentElement(
+          range->GetStartContainer());
+    }
+  }
+
+  // If there is no selection ranges, use the <body> or <frameset> element.
+  if (!targetElement) {
+    targetElement = doc->GetBody();
+    if (!targetElement) {
+      return false;
+    }
+  }
+
+  // It seems to be unsafe to fire an event handler during reflow (bug 393696)
+  if (!nsContentUtils::IsSafeToRunScript()) {
+    nsContentUtils::WarnScriptWasIgnored(doc);
+    return false;
+  }
+
+  BrowsingContext* bc = piWindow->GetBrowsingContext();
+  const bool chromeShell = bc && bc->IsChrome();
+
+  // next, fire the cut, copy or paste event
+  bool doDefault = true;
+  RefPtr<DataTransfer> clipboardData;
+  if (chromeShell || StaticPrefs::dom_event_clipboardevents_enabled()) {
+    clipboardData =
+        new DataTransfer(doc->GetScopeObject(), aEventMessage,
+                         originalEventMessage == ePaste, aClipboardType);
+
+    nsEventStatus status = nsEventStatus_eIgnore;
+    InternalClipboardEvent evt(true, originalEventMessage);
+    evt.mClipboardData = clipboardData;
+
+    RefPtr<nsPresContext> presContext = presShell->GetPresContext();
+    EventDispatcher::Dispatch(targetElement, presContext, &evt, nullptr,
+                              &status);
+    // If the event was cancelled, don't do the clipboard operation
+    doDefault = (status != nsEventStatus_eConsumeNoDefault);
+  }
+
+  // When this function exits, the event dispatch is over. We want to disconnect
+  // our DataTransfer, which means setting its mode to `Protected` and clearing
+  // all stored data, before we return.
+  auto clearAfter = MakeScopeExit([&] {
+    if (clipboardData) {
+      clipboardData->Disconnect();
+
+      // NOTE: Disconnect may not actually clear the DataTransfer if the
+      // dom.events.dataTransfer.protected.enabled pref is not on, so we make
+      // sure we clear here, as not clearing could provide the DataTransfer
+      // access to information from the system clipboard at an arbitrary point
+      // in the future.
+      if (originalEventMessage == ePaste) {
+        clipboardData->ClearAll();
+      }
+    }
+  });
+
+  // No need to do anything special during a paste. Either an event listener
+  // took care of it and cancelled the event, or the caller will handle it.
+  // Return true to indicate that the event wasn't cancelled.
+  if (originalEventMessage == ePaste) {
+    if (aActionTaken) {
+      *aActionTaken = true;
+    }
+    return doDefault;
+  }
+
+  // Update the presentation in case the event handler modified the selection,
+  // see bug 602231.
+  presShell->FlushPendingNotifications(FlushType::Frames);
+  if (presShell->IsDestroying()) {
+    return false;
+  }
+
+  // if the event was not cancelled, do the default copy. If the event was
+  // cancelled, use the data added to the data transfer and copy that instead.
+  uint32_t count = 0;
+  if (doDefault) {
+    // find the focused node
+    nsIContent* sourceContent = targetElement.get();
+    if (targetElement->IsInNativeAnonymousSubtree()) {
+      sourceContent = targetElement->FindFirstNonChromeOnlyAccessContent();
+    }
+
+    // If it's <input type="password"> and there is no unmasked range or
+    // there is unmasked range but it's collapsed or it'll be masked
+    // automatically, the selected password shouldn't be copied into the
+    // clipboard.
+    if (RefPtr<HTMLInputElement> inputElement =
+            HTMLInputElement::FromNodeOrNull(sourceContent)) {
+      if (TextEditor* textEditor = inputElement->GetTextEditor()) {
+        if (textEditor->IsPasswordEditor() &&
+            !textEditor->IsCopyToClipboardAllowed()) {
+          return false;
+        }
+      }
+    }
+
+    // when cutting non-editable content, do nothing
+    // XXX this is probably the wrong editable flag to check
+    if (originalEventMessage != eCut || targetElement->IsEditable()) {
+      // get the data from the selection if any
+      if (sel->IsCollapsed()) {
+        if (aActionTaken) {
+          *aActionTaken = true;
+        }
+        return false;
+      }
+      // XXX Code which decides whether we should copy text with ruby
+      // annotation is currenct depending on whether each range of the
+      // selection is inside a same ruby container. But we really should
+      // expose the full functionality in browser. See bug 1130891.
+      bool withRubyAnnotation = IsSelectionInsideRuby(sel);
+      nsresult rv = EncodeDocumentWithContextAndPutToClipboard(
+          sel, doc, aClipboardType, withRubyAnnotation);
+      if (NS_FAILED(rv)) {
+        return false;
+      }
+    } else {
+      return false;
+    }
+  } else if (clipboardData) {
+    // check to see if any data was put on the data transfer.
+    count = clipboardData->MozItemCount();
+    if (count) {
+      nsCOMPtr<nsIClipboard> clipboard(
+          do_GetService("@mozilla.org/widget/clipboard;1"));
+      NS_ENSURE_TRUE(clipboard, false);
+
+      nsCOMPtr<nsITransferable> transferable =
+          clipboardData->GetTransferable(0, doc->GetLoadContext());
+
+      NS_ENSURE_TRUE(transferable, false);
+
+      // put the transferable on the clipboard
+      nsresult rv = clipboard->SetData(transferable, nullptr, aClipboardType);
+      if (NS_FAILED(rv)) {
+        return false;
+      }
+    }
+  }
+
+  // Now that we have copied, update the clipboard commands. This should have
+  // the effect of updating the enabled state of the paste menu item.
+  if (doDefault || count) {
+    piWindow->UpdateCommands(u"clipboard"_ns, nullptr, 0);
+  }
+
+  if (aActionTaken) {
+    *aActionTaken = true;
+  }
+  return doDefault;
+}