dom/serializers/nsDOMSerializer.cpp

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=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 "nsDOMSerializer.h"
   8
   9 #include "mozilla/Encoding.h"
  10 #include "mozilla/dom/Document.h"
  11 #include "nsIDocumentEncoder.h"
  12 #include "nsComponentManagerUtils.h"
  13 #include "nsContentCID.h"
  14 #include "nsContentUtils.h"
  15 #include "nsError.h"
  16 #include "nsINode.h"
  17
  18 using namespace mozilla;
  19
  20 nsDOMSerializer::nsDOMSerializer() = default;
  21
  22 static already_AddRefed<nsIDocumentEncoder> SetUpEncoder(
  23     nsINode& aRoot, const nsAString& aCharset, ErrorResult& aRv) {
  24   nsCOMPtr<nsIDocumentEncoder> encoder =
  25       do_createDocumentEncoder("application/xhtml+xml");
  26   if (!encoder) {
  27     aRv.Throw(NS_ERROR_FAILURE);
  28     return nullptr;
  29   }
  30
  31   dom::Document* doc = aRoot.OwnerDoc();
  32   bool entireDocument = (doc == &aRoot);
  33
  34   // This method will fail if no document
  35   nsresult rv = encoder->NativeInit(
  36       doc, u"application/xhtml+xml"_ns,
  37       nsIDocumentEncoder::OutputRaw |
  38           nsIDocumentEncoder::OutputDontRewriteEncodingDeclaration);
  39
  40   if (NS_FAILED(rv)) {
  41     aRv.Throw(rv);
  42     return nullptr;
  43   }
  44
  45   NS_ConvertUTF16toUTF8 charset(aCharset);
  46   if (charset.IsEmpty()) {
  47     doc->GetDocumentCharacterSet()->Name(charset);
  48   }
  49   rv = encoder->SetCharset(charset);
  50   if (NS_FAILED(rv)) {
  51     aRv.Throw(rv);
  52     return nullptr;
  53   }
  54
  55   // If we are working on the entire document we do not need to
  56   // specify which part to serialize
  57   if (!entireDocument) {
  58     rv = encoder->SetNode(&aRoot);
  59   }
  60
  61   if (NS_FAILED(rv)) {
  62     aRv.Throw(rv);
  63     return nullptr;
  64   }
  65
  66   return encoder.forget();
  67 }
  68
  69 void nsDOMSerializer::SerializeToString(nsINode& aRoot, nsAString& aStr,
  70                                         ErrorResult& aRv) {
  71   aStr.Truncate();
  72
  73   if (!nsContentUtils::CanCallerAccess(&aRoot)) {
  74     aRv.Throw(NS_ERROR_DOM_SECURITY_ERR);
  75     return;
  76   }
  77
  78   nsCOMPtr<nsIDocumentEncoder> encoder = SetUpEncoder(aRoot, u""_ns, aRv);
  79   if (aRv.Failed()) {
  80     return;
  81   }
  82
  83   nsresult rv = encoder->EncodeToString(aStr);
  84   if (NS_FAILED(rv)) {
  85     aRv.Throw(rv);
  86   }
  87 }
  88
  89 void nsDOMSerializer::SerializeToStream(nsINode& aRoot,
  90                                         nsIOutputStream* aStream,
  91                                         const nsAString& aCharset,
  92                                         ErrorResult& aRv) {
  93   if (NS_WARN_IF(!aStream)) {
  94     aRv.Throw(NS_ERROR_INVALID_ARG);
  95     return;
  96   }
  97
  98   // The charset arg can be empty, in which case we get the document's
  99   // charset and use that when serializing.
 100
 101   // No point doing a CanCallerAccess check, because we can only be
 102   // called by system JS or C++.
 103   nsCOMPtr<nsIDocumentEncoder> encoder = SetUpEncoder(aRoot, aCharset, aRv);
 104   if (aRv.Failed()) {
 105     return;
 106   }
 107
 108   nsresult rv = encoder->EncodeToStream(aStream);
 109   if (NS_FAILED(rv)) {
 110     aRv.Throw(rv);
 111   }
 112 }