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/* -*- 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
#include "nsStringEnumerator.h"
#include "nsSimpleEnumerator.h"
#include "nsSupportsPrimitives.h"
#include "mozilla/Attributes.h"
#include "mozilla/ResultExtensions.h"
#include "mozilla/Try.h"
#include "mozilla/dom/IteratorResultBinding.h"
#include "mozilla/dom/RootedDictionary.h"
#include "mozilla/dom/ToJSValue.h"
#include "nsTArray.h"
using namespace mozilla;
using namespace mozilla::dom;
namespace {
class JSStringEnumerator final : public nsIJSEnumerator {
NS_DECL_ISUPPORTS
NS_DECL_NSIJSENUMERATOR
explicit JSStringEnumerator(nsIStringEnumerator* aEnumerator)
: mEnumerator(aEnumerator) {
MOZ_ASSERT(mEnumerator);
}
private:
~JSStringEnumerator() = default;
nsCOMPtr<nsIStringEnumerator> mEnumerator;
};
} // anonymous namespace
nsresult JSStringEnumerator::Iterator(nsIJSEnumerator** aResult) {
RefPtr<JSStringEnumerator> result(this);
result.forget(aResult);
return NS_OK;
}
nsresult JSStringEnumerator::Next(JSContext* aCx,
JS::MutableHandleValue aResult) {
RootedDictionary<IteratorResult> result(aCx);
nsAutoString elem;
if (NS_FAILED(mEnumerator->GetNext(elem))) {
result.mDone = true;
} else {
result.mDone = false;
if (!ToJSValue(
aCx, elem,
JS::MutableHandleValue::fromMarkedLocation(&result.mValue))) {
return NS_ERROR_OUT_OF_MEMORY;
}
}
if (!ToJSValue(aCx, result, aResult)) {
return NS_ERROR_OUT_OF_MEMORY;
}
return NS_OK;
}
NS_IMPL_ISUPPORTS(JSStringEnumerator, nsIJSEnumerator)
//
// nsStringEnumeratorBase
//
nsresult nsStringEnumeratorBase::GetNext(nsAString& aResult) {
nsAutoCString str;
MOZ_TRY(GetNext(str));
CopyUTF8toUTF16(str, aResult);
return NS_OK;
}
NS_IMETHODIMP
nsStringEnumeratorBase::StringIterator(nsIJSEnumerator** aRetVal) {
auto result = MakeRefPtr<JSStringEnumerator>(this);
result.forget(aRetVal);
return NS_OK;
}
//
// nsStringEnumerator
//
class nsStringEnumerator final : public nsSimpleEnumerator,
public nsIStringEnumerator,
public nsIUTF8StringEnumerator {
public:
nsStringEnumerator(const nsTArray<nsString>* aArray, bool aOwnsArray)
: mArray(aArray), mIndex(0), mOwnsArray(aOwnsArray), mIsUnicode(true) {}
nsStringEnumerator(const nsTArray<nsCString>* aArray, bool aOwnsArray)
: mCArray(aArray), mIndex(0), mOwnsArray(aOwnsArray), mIsUnicode(false) {}
nsStringEnumerator(const nsTArray<nsString>* aArray, nsISupports* aOwner)
: mArray(aArray),
mIndex(0),
mOwner(aOwner),
mOwnsArray(false),
mIsUnicode(true) {}
nsStringEnumerator(const nsTArray<nsCString>* aArray, nsISupports* aOwner)
: mCArray(aArray),
mIndex(0),
mOwner(aOwner),
mOwnsArray(false),
mIsUnicode(false) {}
NS_DECL_ISUPPORTS_INHERITED
NS_DECL_NSIUTF8STRINGENUMERATOR
NS_DECL_NSISTRINGENUMERATORBASE
// have to declare nsIStringEnumerator manually, because of
// overlapping method names
NS_IMETHOD GetNext(nsAString& aResult) override;
NS_DECL_NSISIMPLEENUMERATOR
const nsID& DefaultInterface() override {
if (mIsUnicode) {
return NS_GET_IID(nsISupportsString);
}
return NS_GET_IID(nsISupportsCString);
}
private:
~nsStringEnumerator() {
if (mOwnsArray) {
// const-casting is safe here, because the NS_New*
// constructors make sure mOwnsArray is consistent with
// the constness of the objects
if (mIsUnicode) {
delete const_cast<nsTArray<nsString>*>(mArray);
} else {
delete const_cast<nsTArray<nsCString>*>(mCArray);
}
}
}
union {
const nsTArray<nsString>* mArray;
const nsTArray<nsCString>* mCArray;
};
inline uint32_t Count() {
return mIsUnicode ? mArray->Length() : mCArray->Length();
}
uint32_t mIndex;
// the owner allows us to hold a strong reference to the object
// that owns the array. Having a non-null value in mOwner implies
// that mOwnsArray is false, because we rely on the real owner
// to release the array
nsCOMPtr<nsISupports> mOwner;
bool mOwnsArray;
bool mIsUnicode;
};
NS_IMPL_ISUPPORTS_INHERITED(nsStringEnumerator, nsSimpleEnumerator,
nsIStringEnumerator, nsIUTF8StringEnumerator)
NS_IMETHODIMP
nsStringEnumerator::HasMore(bool* aResult) {
*aResult = mIndex < Count();
return NS_OK;
}
NS_IMETHODIMP
nsStringEnumerator::HasMoreElements(bool* aResult) { return HasMore(aResult); }
NS_IMETHODIMP
nsStringEnumerator::GetNext(nsISupports** aResult) {
if (mIndex >= mArray->Length()) {
return NS_ERROR_FAILURE;
}
if (mIsUnicode) {
nsSupportsString* stringImpl = new nsSupportsString();
stringImpl->SetData(mArray->ElementAt(mIndex++));
*aResult = stringImpl;
} else {
nsSupportsCString* cstringImpl = new nsSupportsCString();
cstringImpl->SetData(mCArray->ElementAt(mIndex++));
*aResult = cstringImpl;
}
NS_ADDREF(*aResult);
return NS_OK;
}
NS_IMETHODIMP
nsStringEnumerator::GetNext(nsAString& aResult) {
if (NS_WARN_IF(mIndex >= Count())) {
return NS_ERROR_UNEXPECTED;
}
if (mIsUnicode) {
aResult = mArray->ElementAt(mIndex++);
} else {
CopyUTF8toUTF16(mCArray->ElementAt(mIndex++), aResult);
}
return NS_OK;
}
NS_IMETHODIMP
nsStringEnumerator::GetNext(nsACString& aResult) {
if (NS_WARN_IF(mIndex >= Count())) {
return NS_ERROR_UNEXPECTED;
}
if (mIsUnicode) {
CopyUTF16toUTF8(mArray->ElementAt(mIndex++), aResult);
} else {
aResult = mCArray->ElementAt(mIndex++);
}
return NS_OK;
}
NS_IMETHODIMP
nsStringEnumerator::StringIterator(nsIJSEnumerator** aRetVal) {
auto result = MakeRefPtr<JSStringEnumerator>(this);
result.forget(aRetVal);
return NS_OK;
}
template <class T>
static inline nsresult StringEnumeratorTail(T** aResult) {
if (!*aResult) {
return NS_ERROR_OUT_OF_MEMORY;
}
NS_ADDREF(*aResult);
return NS_OK;
}
//
// constructors
//
nsresult NS_NewStringEnumerator(nsIStringEnumerator** aResult,
const nsTArray<nsString>* aArray,
nsISupports* aOwner) {
if (NS_WARN_IF(!aResult) || NS_WARN_IF(!aArray)) {
return NS_ERROR_INVALID_ARG;
}
*aResult = new nsStringEnumerator(aArray, aOwner);
return StringEnumeratorTail(aResult);
}
nsresult NS_NewUTF8StringEnumerator(nsIUTF8StringEnumerator** aResult,
const nsTArray<nsCString>* aArray,
nsISupports* aOwner) {
if (NS_WARN_IF(!aResult) || NS_WARN_IF(!aArray)) {
return NS_ERROR_INVALID_ARG;
}
*aResult = new nsStringEnumerator(aArray, aOwner);
return StringEnumeratorTail(aResult);
}
nsresult NS_NewAdoptingStringEnumerator(nsIStringEnumerator** aResult,
nsTArray<nsString>* aArray) {
if (NS_WARN_IF(!aResult) || NS_WARN_IF(!aArray)) {
return NS_ERROR_INVALID_ARG;
}
*aResult = new nsStringEnumerator(aArray, true);
return StringEnumeratorTail(aResult);
}
nsresult NS_NewAdoptingUTF8StringEnumerator(nsIUTF8StringEnumerator** aResult,
nsTArray<nsCString>* aArray) {
if (NS_WARN_IF(!aResult) || NS_WARN_IF(!aArray)) {
return NS_ERROR_INVALID_ARG;
}
*aResult = new nsStringEnumerator(aArray, true);
return StringEnumeratorTail(aResult);
}
// const ones internally just forward to the non-const equivalents
nsresult NS_NewStringEnumerator(nsIStringEnumerator** aResult,
const nsTArray<nsString>* aArray) {
if (NS_WARN_IF(!aResult) || NS_WARN_IF(!aArray)) {
return NS_ERROR_INVALID_ARG;
}
*aResult = new nsStringEnumerator(aArray, false);
return StringEnumeratorTail(aResult);
}
nsresult NS_NewUTF8StringEnumerator(nsIUTF8StringEnumerator** aResult,
const nsTArray<nsCString>* aArray) {
if (NS_WARN_IF(!aResult) || NS_WARN_IF(!aArray)) {
return NS_ERROR_INVALID_ARG;
}
*aResult = new nsStringEnumerator(aArray, false);
return StringEnumeratorTail(aResult);
}