xpcom/ds/nsSimpleEnumerator.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 "nsSimpleEnumerator.h"
   8
   9 #include "mozilla/dom/IteratorResultBinding.h"
  10 #include "mozilla/dom/RootedDictionary.h"
  11 #include "mozilla/dom/ToJSValue.h"
  12 #include "mozilla/ResultExtensions.h"
  13 #include "mozilla/Try.h"
  14 #include "nsContentUtils.h"
  15
  16 using namespace mozilla;
  17 using namespace mozilla::dom;
  18
  19 namespace {
  20
  21 class JSEnumerator final : public nsIJSEnumerator {
  22   NS_DECL_ISUPPORTS
  23   NS_DECL_NSIJSENUMERATOR
  24
  25   explicit JSEnumerator(nsISimpleEnumerator* aEnumerator, const nsID& aIID)
  26       : mEnumerator(aEnumerator), mIID(aIID) {}
  27
  28  private:
  29   ~JSEnumerator() = default;
  30
  31   nsCOMPtr<nsISimpleEnumerator> mEnumerator;
  32   const nsID mIID;
  33 };
  34
  35 }  // anonymous namespace
  36
  37 nsresult JSEnumerator::Iterator(nsIJSEnumerator** aResult) {
  38   RefPtr<JSEnumerator> result(this);
  39   result.forget(aResult);
  40   return NS_OK;
  41 }
  42
  43 nsresult JSEnumerator::Next(JSContext* aCx, JS::MutableHandleValue aResult) {
  44   RootedDictionary<IteratorResult> result(aCx);
  45
  46   nsCOMPtr<nsISupports> elem;
  47   if (NS_FAILED(mEnumerator->GetNext(getter_AddRefs(elem)))) {
  48     result.mDone = true;
  49   } else {
  50     result.mDone = false;
  51
  52     JS::RootedValue value(aCx);
  53     MOZ_TRY(nsContentUtils::WrapNative(aCx, elem, &mIID, &value));
  54     result.mValue = value;
  55   }
  56
  57   if (!ToJSValue(aCx, result, aResult)) {
  58     return NS_ERROR_OUT_OF_MEMORY;
  59   }
  60   return NS_OK;
  61 }
  62
  63 NS_IMPL_ISUPPORTS(JSEnumerator, nsIJSEnumerator)
  64
  65 nsresult nsSimpleEnumerator::Iterator(nsIJSEnumerator** aResult) {
  66   auto result = MakeRefPtr<JSEnumerator>(this, DefaultInterface());
  67   result.forget(aResult);
  68   return NS_OK;
  69 }
  70
  71 nsresult nsSimpleEnumerator::Entries(const nsIID& aIface,
  72                                      nsIJSEnumerator** aResult) {
  73   auto result = MakeRefPtr<JSEnumerator>(this, aIface);
  74   result.forget(aResult);
  75   return NS_OK;
  76 }
  77
  78 NS_IMPL_ISUPPORTS(nsSimpleEnumerator, nsISimpleEnumerator,
  79                   nsISimpleEnumeratorBase)