gecko-dev/xpcom/ds/nsCOMArray.cpp
2019-05-16 15:13:44 +00:00

253 lines
7.1 KiB
C++

/* -*- 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 "nsCOMArray.h"
#include "mozilla/MemoryReporting.h"
#include "mozilla/OperatorNewExtensions.h"
#include "nsQuickSort.h"
#include "nsCOMPtr.h"
// This specialization is private to nsCOMArray.
// It exists solely to automatically zero-out newly created array elements.
template <>
class nsTArrayElementTraits<nsISupports*> {
typedef nsISupports* E;
public:
// Zero out the value
static inline void Construct(E* aE) {
new (mozilla::KnownNotNull, static_cast<void*>(aE)) E();
}
// Invoke the copy-constructor in place.
template <class A>
static inline void Construct(E* aE, const A& aArg) {
new (mozilla::KnownNotNull, static_cast<void*>(aE)) E(aArg);
}
// Invoke the destructor in place.
static inline void Destruct(E* aE) { aE->~E(); }
};
static void ReleaseObjects(nsTArray<nsISupports*>& aArray);
// implementations of non-trivial methods in nsCOMArray_base
nsCOMArray_base::nsCOMArray_base(const nsCOMArray_base& aOther) {
// make sure we do only one allocation
mArray.SetCapacity(aOther.Count());
AppendObjects(aOther);
}
nsCOMArray_base::~nsCOMArray_base() { Clear(); }
int32_t nsCOMArray_base::IndexOf(nsISupports* aObject,
uint32_t aStartIndex) const {
return mArray.IndexOf(aObject, aStartIndex);
}
int32_t nsCOMArray_base::IndexOfObject(nsISupports* aObject) const {
nsCOMPtr<nsISupports> supports = do_QueryInterface(aObject);
if (NS_WARN_IF(!supports)) {
return -1;
}
uint32_t i, count;
int32_t retval = -1;
count = mArray.Length();
for (i = 0; i < count; ++i) {
nsCOMPtr<nsISupports> arrayItem = do_QueryInterface(mArray[i]);
if (arrayItem == supports) {
retval = i;
break;
}
}
return retval;
}
bool nsCOMArray_base::EnumerateForwards(nsBaseArrayEnumFunc aFunc,
void* aData) const {
for (uint32_t index = 0; index < mArray.Length(); ++index) {
if (!(*aFunc)(mArray[index], aData)) {
return false;
}
}
return true;
}
bool nsCOMArray_base::EnumerateBackwards(nsBaseArrayEnumFunc aFunc,
void* aData) const {
for (uint32_t index = mArray.Length(); index--;) {
if (!(*aFunc)(mArray[index], aData)) {
return false;
}
}
return true;
}
int nsCOMArray_base::nsCOMArrayComparator(const void* aElement1,
const void* aElement2, void* aData) {
nsCOMArrayComparatorContext* ctx =
static_cast<nsCOMArrayComparatorContext*>(aData);
return (*ctx->mComparatorFunc)(*static_cast<nsISupports* const*>(aElement1),
*static_cast<nsISupports* const*>(aElement2),
ctx->mData);
}
void nsCOMArray_base::Sort(nsBaseArrayComparatorFunc aFunc, void* aData) {
if (mArray.Length() > 1) {
nsCOMArrayComparatorContext ctx = {aFunc, aData};
NS_QuickSort(mArray.Elements(), mArray.Length(), sizeof(nsISupports*),
nsCOMArrayComparator, &ctx);
}
}
bool nsCOMArray_base::InsertObjectAt(nsISupports* aObject, int32_t aIndex) {
if ((uint32_t)aIndex > mArray.Length()) {
return false;
}
if (!mArray.InsertElementAt(aIndex, aObject)) {
return false;
}
NS_IF_ADDREF(aObject);
return true;
}
void nsCOMArray_base::InsertElementAt(uint32_t aIndex, nsISupports* aElement) {
mArray.InsertElementAt(aIndex, aElement);
NS_IF_ADDREF(aElement);
}
void nsCOMArray_base::InsertElementAt(uint32_t aIndex,
already_AddRefed<nsISupports> aElement) {
mArray.InsertElementAt(aIndex, aElement.take());
}
bool nsCOMArray_base::InsertObjectsAt(const nsCOMArray_base& aObjects,
int32_t aIndex) {
if ((uint32_t)aIndex > mArray.Length()) {
return false;
}
if (!mArray.InsertElementsAt(aIndex, aObjects.mArray)) {
return false;
}
// need to addref all these
uint32_t count = aObjects.Length();
for (uint32_t i = 0; i < count; ++i) {
NS_IF_ADDREF(aObjects[i]);
}
return true;
}
void nsCOMArray_base::InsertElementsAt(uint32_t aIndex,
const nsCOMArray_base& aElements) {
mArray.InsertElementsAt(aIndex, aElements.mArray);
// need to addref all these
uint32_t count = aElements.Length();
for (uint32_t i = 0; i < count; ++i) {
NS_IF_ADDREF(aElements[i]);
}
}
void nsCOMArray_base::InsertElementsAt(uint32_t aIndex,
nsISupports* const* aElements,
uint32_t aCount) {
mArray.InsertElementsAt(aIndex, aElements, aCount);
// need to addref all these
for (uint32_t i = 0; i < aCount; ++i) {
NS_IF_ADDREF(aElements[i]);
}
}
void nsCOMArray_base::ReplaceObjectAt(nsISupports* aObject, int32_t aIndex) {
mArray.EnsureLengthAtLeast(aIndex + 1);
nsISupports* oldObject = mArray[aIndex];
// Make sure to addref first, in case aObject == oldObject
NS_IF_ADDREF(mArray[aIndex] = aObject);
NS_IF_RELEASE(oldObject);
}
bool nsCOMArray_base::RemoveObject(nsISupports* aObject) {
bool result = mArray.RemoveElement(aObject);
if (result) {
NS_IF_RELEASE(aObject);
}
return result;
}
bool nsCOMArray_base::RemoveObjectAt(int32_t aIndex) {
if (uint32_t(aIndex) < mArray.Length()) {
nsISupports* element = mArray[aIndex];
mArray.RemoveElementAt(aIndex);
NS_IF_RELEASE(element);
return true;
}
return false;
}
void nsCOMArray_base::RemoveElementAt(uint32_t aIndex) {
nsISupports* element = mArray[aIndex];
mArray.RemoveElementAt(aIndex);
NS_IF_RELEASE(element);
}
bool nsCOMArray_base::RemoveObjectsAt(int32_t aIndex, int32_t aCount) {
if (uint32_t(aIndex) + uint32_t(aCount) <= mArray.Length()) {
nsTArray<nsISupports*> elementsToDestroy(aCount);
elementsToDestroy.AppendElements(mArray.Elements() + aIndex, aCount);
mArray.RemoveElementsAt(aIndex, aCount);
ReleaseObjects(elementsToDestroy);
return true;
}
return false;
}
void nsCOMArray_base::RemoveElementsAt(uint32_t aIndex, uint32_t aCount) {
nsTArray<nsISupports*> elementsToDestroy(aCount);
elementsToDestroy.AppendElements(mArray.Elements() + aIndex, aCount);
mArray.RemoveElementsAt(aIndex, aCount);
ReleaseObjects(elementsToDestroy);
}
// useful for destructors
void ReleaseObjects(nsTArray<nsISupports*>& aArray) {
for (uint32_t i = 0; i < aArray.Length(); ++i) {
NS_IF_RELEASE(aArray[i]);
}
}
void nsCOMArray_base::Clear() {
nsTArray<nsISupports*> objects;
objects.SwapElements(mArray);
ReleaseObjects(objects);
}
bool nsCOMArray_base::SetCount(int32_t aNewCount) {
NS_ASSERTION(aNewCount >= 0, "SetCount(negative index)");
if (aNewCount < 0) {
return false;
}
int32_t count = mArray.Length();
if (count > aNewCount) {
RemoveObjectsAt(aNewCount, mArray.Length() - aNewCount);
}
mArray.SetLength(aNewCount);
return true;
}