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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-19 00:47:55 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-19 00:47:55 +0000 |
commit | 26a029d407be480d791972afb5975cf62c9360a6 (patch) | |
tree | f435a8308119effd964b339f76abb83a57c29483 /xpcom/ds/nsCOMArray.h | |
parent | Initial commit. (diff) | |
download | firefox-e51783d008170d9ab27d25da98ca3a38b0a41b67.tar.xz firefox-e51783d008170d9ab27d25da98ca3a38b0a41b67.zip |
Adding upstream version 124.0.1.upstream/124.0.1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'xpcom/ds/nsCOMArray.h')
-rw-r--r-- | xpcom/ds/nsCOMArray.h | 387 |
1 files changed, 387 insertions, 0 deletions
diff --git a/xpcom/ds/nsCOMArray.h b/xpcom/ds/nsCOMArray.h new file mode 100644 index 0000000000..9b2abb3cbf --- /dev/null +++ b/xpcom/ds/nsCOMArray.h @@ -0,0 +1,387 @@ +/* -*- 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/. */ + +#ifndef nsCOMArray_h__ +#define nsCOMArray_h__ + +#include "mozilla/Attributes.h" +#include "mozilla/ArrayIterator.h" +#include "mozilla/MemoryReporting.h" + +#include "nsCycleCollectionNoteChild.h" +#include "nsTArray.h" +#include "nsISupports.h" + +#include <iterator> + +// See below for the definition of nsCOMArray<T> + +// a class that's nsISupports-specific, so that we can contain the +// work of this class in the XPCOM dll +class nsCOMArray_base { + friend class nsArrayBase; + + protected: + nsCOMArray_base() = default; + explicit nsCOMArray_base(int32_t aCount) : mArray(aCount) {} + nsCOMArray_base(const nsCOMArray_base& aOther); + nsCOMArray_base(nsCOMArray_base&& aOther) = default; + nsCOMArray_base& operator=(nsCOMArray_base&& aOther) = default; + ~nsCOMArray_base(); + + int32_t IndexOf(nsISupports* aObject, uint32_t aStartIndex = 0) const; + bool Contains(nsISupports* aObject) const { return IndexOf(aObject) != -1; } + + int32_t IndexOfObject(nsISupports* aObject) const; + bool ContainsObject(nsISupports* aObject) const { + return IndexOfObject(aObject) != -1; + } + + typedef bool (*nsBaseArrayEnumFunc)(void* aElement, void* aData); + + // enumerate through the array with a callback. + bool EnumerateForwards(nsBaseArrayEnumFunc aFunc, void* aData) const; + + bool EnumerateBackwards(nsBaseArrayEnumFunc aFunc, void* aData) const; + + bool InsertObjectAt(nsISupports* aObject, int32_t aIndex); + void InsertElementAt(uint32_t aIndex, nsISupports* aElement); + void InsertElementAt(uint32_t aIndex, already_AddRefed<nsISupports> aElement); + bool InsertObjectsAt(const nsCOMArray_base& aObjects, int32_t aIndex); + void InsertElementsAt(uint32_t aIndex, const nsCOMArray_base& aElements); + void InsertElementsAt(uint32_t aIndex, nsISupports* const* aElements, + uint32_t aCount); + void ReplaceObjectAt(nsISupports* aObject, int32_t aIndex); + void ReplaceElementAt(uint32_t aIndex, nsISupports* aElement) { + nsISupports* oldElement = mArray[aIndex]; + NS_IF_ADDREF(mArray[aIndex] = aElement); + NS_IF_RELEASE(oldElement); + } + bool AppendObject(nsISupports* aObject) { + return InsertObjectAt(aObject, Count()); + } + void AppendElement(nsISupports* aElement) { + InsertElementAt(Length(), aElement); + } + void AppendElement(already_AddRefed<nsISupports> aElement) { + InsertElementAt(Length(), std::move(aElement)); + } + + bool AppendObjects(const nsCOMArray_base& aObjects) { + return InsertObjectsAt(aObjects, Count()); + } + void AppendElements(const nsCOMArray_base& aElements) { + return InsertElementsAt(Length(), aElements); + } + void AppendElements(nsISupports* const* aElements, uint32_t aCount) { + return InsertElementsAt(Length(), aElements, aCount); + } + bool RemoveObject(nsISupports* aObject); + nsISupports** Elements() { return mArray.Elements(); } + void SwapElements(nsCOMArray_base& aOther) { + mArray.SwapElements(aOther.mArray); + } + + public: + // elements in the array (including null elements!) + int32_t Count() const { return mArray.Length(); } + // nsTArray-compatible version + uint32_t Length() const { return mArray.Length(); } + bool IsEmpty() const { return mArray.IsEmpty(); } + + // If the array grows, the newly created entries will all be null; + // if the array shrinks, the excess entries will all be released. + bool SetCount(int32_t aNewCount); + // nsTArray-compatible version + void TruncateLength(uint32_t aNewLength) { + if (mArray.Length() > aNewLength) { + RemoveElementsAt(aNewLength, mArray.Length() - aNewLength); + } + } + + // remove all elements in the array, and call NS_RELEASE on each one + void Clear(); + + nsISupports* ObjectAt(int32_t aIndex) const { return mArray[aIndex]; } + // nsTArray-compatible version + nsISupports* ElementAt(uint32_t aIndex) const { return mArray[aIndex]; } + + nsISupports* SafeObjectAt(int32_t aIndex) const { + return mArray.SafeElementAt(aIndex, nullptr); + } + // nsTArray-compatible version + nsISupports* SafeElementAt(uint32_t aIndex) const { + return mArray.SafeElementAt(aIndex, nullptr); + } + + nsISupports* operator[](int32_t aIndex) const { return mArray[aIndex]; } + + // remove an element at a specific position, shrinking the array + // as necessary + bool RemoveObjectAt(int32_t aIndex); + // nsTArray-compatible version + void RemoveElementAt(uint32_t aIndex); + + // remove a range of elements at a specific position, shrinking the array + // as necessary + bool RemoveObjectsAt(int32_t aIndex, int32_t aCount); + // nsTArray-compatible version + void RemoveElementsAt(uint32_t aIndex, uint32_t aCount); + + void SwapElementsAt(uint32_t aIndex1, uint32_t aIndex2) { + nsISupports* tmp = mArray[aIndex1]; + mArray[aIndex1] = mArray[aIndex2]; + mArray[aIndex2] = tmp; + } + + // Ensures there is enough space to store a total of aCapacity objects. + // This method never deletes any objects. + void SetCapacity(uint32_t aCapacity) { mArray.SetCapacity(aCapacity); } + uint32_t Capacity() { return mArray.Capacity(); } + + // Measures the size of the array's element storage. If you want to measure + // anything hanging off the array, you must iterate over the elements and + // measure them individually; hence the "Shallow" prefix. Note that because + // each element in an nsCOMArray<T> is actually a T* any such iteration + // should use a SizeOfIncludingThis() function on each element rather than a + // SizeOfExcludingThis() function, so that the memory taken by the T itself + // is included as well as anything it points to. + size_t ShallowSizeOfExcludingThis(mozilla::MallocSizeOf aMallocSizeOf) const { + return mArray.ShallowSizeOfExcludingThis(aMallocSizeOf); + } + + protected: + // the actual storage + nsTArray<nsISupports*> mArray; + + private: + // don't implement these, defaults will muck with refcounts! + nsCOMArray_base& operator=(const nsCOMArray_base& aOther) = delete; +}; + +inline void ImplCycleCollectionUnlink(nsCOMArray_base& aField) { + aField.Clear(); +} + +inline void ImplCycleCollectionTraverse( + nsCycleCollectionTraversalCallback& aCallback, nsCOMArray_base& aField, + const char* aName, uint32_t aFlags = 0) { + aFlags |= CycleCollectionEdgeNameArrayFlag; + int32_t length = aField.Count(); + for (int32_t i = 0; i < length; ++i) { + CycleCollectionNoteChild(aCallback, aField[i], aName, aFlags); + } +} + +// a non-XPCOM, refcounting array of XPCOM objects +// used as a member variable or stack variable - this object is NOT +// refcounted, but the objects that it holds are +// +// most of the read-only accessors like ObjectAt()/etc do NOT refcount +// on the way out. This means that you can do one of two things: +// +// * does an addref, but holds onto a reference +// nsCOMPtr<T> foo = array[i]; +// +// * avoids the refcount, but foo might go stale if array[i] is ever +// * modified/removed. Be careful not to NS_RELEASE(foo)! +// T* foo = array[i]; +// +// This array will accept null as an argument for any object, and will store +// null in the array. But that also means that methods like ObjectAt() may +// return null when referring to an existing, but null entry in the array. +template <class T> +class nsCOMArray : public nsCOMArray_base { + public: + typedef int32_t index_type; + typedef mozilla::ArrayIterator<T*, nsCOMArray> iterator; + typedef mozilla::ArrayIterator<const T*, nsCOMArray> const_iterator; + typedef std::reverse_iterator<iterator> reverse_iterator; + typedef std::reverse_iterator<const_iterator> const_reverse_iterator; + + nsCOMArray() = default; + explicit nsCOMArray(int32_t aCount) : nsCOMArray_base(aCount) {} + explicit nsCOMArray(const nsCOMArray<T>& aOther) : nsCOMArray_base(aOther) {} + nsCOMArray(nsCOMArray<T>&& aOther) = default; + ~nsCOMArray() = default; + + // We have a move assignment operator, but no copy assignment operator. + nsCOMArray<T>& operator=(nsCOMArray<T>&& aOther) = default; + + // these do NOT refcount on the way out, for speed + T* ObjectAt(int32_t aIndex) const { + return static_cast<T*>(nsCOMArray_base::ObjectAt(aIndex)); + } + // nsTArray-compatible version + T* ElementAt(uint32_t aIndex) const { + return static_cast<T*>(nsCOMArray_base::ElementAt(aIndex)); + } + + // these do NOT refcount on the way out, for speed + T* SafeObjectAt(int32_t aIndex) const { + return static_cast<T*>(nsCOMArray_base::SafeObjectAt(aIndex)); + } + // nsTArray-compatible version + T* SafeElementAt(uint32_t aIndex) const { + return static_cast<T*>(nsCOMArray_base::SafeElementAt(aIndex)); + } + + // indexing operator for syntactic sugar + T* operator[](int32_t aIndex) const { return ObjectAt(aIndex); } + + // index of the element in question.. does NOT refcount + // note: this does not check COM object identity. Use + // IndexOfObject() for that purpose + int32_t IndexOf(T* aObject, uint32_t aStartIndex = 0) const { + return nsCOMArray_base::IndexOf(aObject, aStartIndex); + } + bool Contains(T* aObject) const { return nsCOMArray_base::Contains(aObject); } + + // index of the element in question.. be careful! + // this is much slower than IndexOf() because it uses + // QueryInterface to determine actual COM identity of the object + // if you need to do this frequently then consider enforcing + // COM object identity before adding/comparing elements + int32_t IndexOfObject(T* aObject) const { + return nsCOMArray_base::IndexOfObject(aObject); + } + bool ContainsObject(nsISupports* aObject) const { + return nsCOMArray_base::ContainsObject(aObject); + } + + // inserts aObject at aIndex, shifting the objects at aIndex and + // later to make space + bool InsertObjectAt(T* aObject, int32_t aIndex) { + return nsCOMArray_base::InsertObjectAt(aObject, aIndex); + } + // nsTArray-compatible version + void InsertElementAt(uint32_t aIndex, T* aElement) { + nsCOMArray_base::InsertElementAt(aIndex, aElement); + } + + // inserts the objects from aObject at aIndex, shifting the + // objects at aIndex and later to make space + bool InsertObjectsAt(const nsCOMArray<T>& aObjects, int32_t aIndex) { + return nsCOMArray_base::InsertObjectsAt(aObjects, aIndex); + } + // nsTArray-compatible version + void InsertElementsAt(uint32_t aIndex, const nsCOMArray<T>& aElements) { + nsCOMArray_base::InsertElementsAt(aIndex, aElements); + } + void InsertElementsAt(uint32_t aIndex, T* const* aElements, uint32_t aCount) { + nsCOMArray_base::InsertElementsAt( + aIndex, reinterpret_cast<nsISupports* const*>(aElements), aCount); + } + + // replaces an existing element. Warning: if the array grows, + // the newly created entries will all be null + void ReplaceObjectAt(T* aObject, int32_t aIndex) { + nsCOMArray_base::ReplaceObjectAt(aObject, aIndex); + } + // nsTArray-compatible version + void ReplaceElementAt(uint32_t aIndex, T* aElement) { + nsCOMArray_base::ReplaceElementAt(aIndex, aElement); + } + + using TComparatorFunc = int (*)(T*, T*); + + // The default sort function uses nsTArray::Sort. + // Note that the order of equal items is unstable with this. + void Sort(TComparatorFunc aFunc) { + mArray.Sort( + [aFunc](nsISupports* const& aLeft, nsISupports* const& aRight) -> int { + return aFunc(static_cast<T*>(aLeft), static_cast<T*>(aRight)); + }); + } + + // Sort with a stable algorithm, uses nsTArray::StableSort. + void StableSort(TComparatorFunc aFunc) { + mArray.StableSort( + [aFunc](nsISupports* const& aLeft, nsISupports* const& aRight) -> int { + return aFunc(static_cast<T*>(aLeft), static_cast<T*>(aRight)); + }); + } + + // append an object, growing the array as necessary + bool AppendObject(T* aObject) { + return nsCOMArray_base::AppendObject(aObject); + } + // nsTArray-compatible version + void AppendElement(T* aElement) { nsCOMArray_base::AppendElement(aElement); } + void AppendElement(already_AddRefed<T> aElement) { + nsCOMArray_base::AppendElement(std::move(aElement)); + } + + // append objects, growing the array as necessary + bool AppendObjects(const nsCOMArray<T>& aObjects) { + return nsCOMArray_base::AppendObjects(aObjects); + } + // nsTArray-compatible version + void AppendElements(const nsCOMArray<T>& aElements) { + return nsCOMArray_base::AppendElements(aElements); + } + void AppendElements(T* const* aElements, uint32_t aCount) { + InsertElementsAt(Length(), aElements, aCount); + } + + // remove the first instance of the given object and shrink the + // array as necessary + // Warning: if you pass null here, it will remove the first null element + bool RemoveObject(T* aObject) { + return nsCOMArray_base::RemoveObject(aObject); + } + // nsTArray-compatible version + bool RemoveElement(T* aElement) { + return nsCOMArray_base::RemoveObject(aElement); + } + + T** Elements() { return reinterpret_cast<T**>(nsCOMArray_base::Elements()); } + void SwapElements(nsCOMArray<T>& aOther) { + nsCOMArray_base::SwapElements(aOther); + } + + // Methods for range-based for loops. + iterator begin() { return iterator(*this, 0); } + const_iterator begin() const { return const_iterator(*this, 0); } + const_iterator cbegin() const { return begin(); } + iterator end() { return iterator(*this, Length()); } + const_iterator end() const { return const_iterator(*this, Length()); } + const_iterator cend() const { return end(); } + + // Methods for reverse iterating. + reverse_iterator rbegin() { return reverse_iterator(end()); } + const_reverse_iterator rbegin() const { + return const_reverse_iterator(end()); + } + const_reverse_iterator crbegin() const { return rbegin(); } + reverse_iterator rend() { return reverse_iterator(begin()); } + const_reverse_iterator rend() const { + return const_reverse_iterator(begin()); + } + const_reverse_iterator crend() const { return rend(); } + + private: + // don't implement these! + nsCOMArray<T>& operator=(const nsCOMArray<T>& aOther) = delete; +}; + +template <typename T> +inline void ImplCycleCollectionUnlink(nsCOMArray<T>& aField) { + aField.Clear(); +} + +template <typename E> +inline void ImplCycleCollectionTraverse( + nsCycleCollectionTraversalCallback& aCallback, nsCOMArray<E>& aField, + const char* aName, uint32_t aFlags = 0) { + aFlags |= CycleCollectionEdgeNameArrayFlag; + int32_t length = aField.Count(); + for (int32_t i = 0; i < length; ++i) { + CycleCollectionNoteChild(aCallback, aField[i], aName, aFlags); + } +} + +#endif |