The Tor Browser / file comparison
comparison: toolkit/components/places/nsMaybeWeakPtr.h
toolkit/components/places/nsMaybeWeakPtr.h
- branch
- TOR_BUG_3246
- changeset 7
- 129ffea94266
equal
deleted
inserted
replaced
| -1:000000000000 | 0:177c7262f36b |
|---|---|
| 1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ | |
| 2 /* This Source Code Form is subject to the terms of the Mozilla Public | |
| 3 * License, v. 2.0. If a copy of the MPL was not distributed with this | |
| 4 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ | |
| 5 | |
| 6 #ifndef nsMaybeWeakPtr_h_ | |
| 7 #define nsMaybeWeakPtr_h_ | |
| 8 | |
| 9 #include "nsCOMPtr.h" | |
| 10 #include "nsWeakReference.h" | |
| 11 #include "nsTArray.h" | |
| 12 #include "nsCycleCollectionNoteChild.h" | |
| 13 | |
| 14 // nsMaybeWeakPtr is a helper object to hold a strong-or-weak reference | |
| 15 // to the template class. It's pretty minimal, but sufficient. | |
| 16 | |
| 17 class nsMaybeWeakPtr_base | |
| 18 { | |
| 19 protected: | |
| 20 // Returns an addref'd pointer to the requested interface | |
| 21 void* GetValueAs(const nsIID& iid) const; | |
| 22 | |
| 23 nsCOMPtr<nsISupports> mPtr; | |
| 24 }; | |
| 25 | |
| 26 template<class T> | |
| 27 class nsMaybeWeakPtr : private nsMaybeWeakPtr_base | |
| 28 { | |
| 29 public: | |
| 30 nsMaybeWeakPtr(nsISupports *ref) { mPtr = ref; } | |
| 31 nsMaybeWeakPtr(const nsCOMPtr<nsIWeakReference> &ref) { mPtr = ref; } | |
| 32 nsMaybeWeakPtr(const nsCOMPtr<T> &ref) { mPtr = ref; } | |
| 33 | |
| 34 bool operator==(const nsMaybeWeakPtr<T> &other) const { | |
| 35 return mPtr == other.mPtr; | |
| 36 } | |
| 37 | |
| 38 operator const nsCOMPtr<T>() const { return GetValue(); } | |
| 39 | |
| 40 protected: | |
| 41 const nsCOMPtr<T> GetValue() const { | |
| 42 return nsCOMPtr<T>(dont_AddRef(static_cast<T*> | |
| 43 (GetValueAs(NS_GET_TEMPLATE_IID(T))))); | |
| 44 } | |
| 45 }; | |
| 46 | |
| 47 // nsMaybeWeakPtrArray is an array of MaybeWeakPtr objects, that knows how to | |
| 48 // grab a weak reference to a given object if requested. It only allows a | |
| 49 // given object to appear in the array once. | |
| 50 | |
| 51 typedef nsTArray< nsMaybeWeakPtr<nsISupports> > isupports_array_type; | |
| 52 nsresult NS_AppendWeakElementBase(isupports_array_type *aArray, | |
| 53 nsISupports *aElement, bool aWeak); | |
| 54 nsresult NS_RemoveWeakElementBase(isupports_array_type *aArray, | |
| 55 nsISupports *aElement); | |
| 56 | |
| 57 template<class T> | |
| 58 class nsMaybeWeakPtrArray : public nsTArray< nsMaybeWeakPtr<T> > | |
| 59 { | |
| 60 public: | |
| 61 nsresult AppendWeakElement(T *aElement, bool aOwnsWeak) | |
| 62 { | |
| 63 return NS_AppendWeakElementBase( | |
| 64 reinterpret_cast<isupports_array_type*>(this), aElement, aOwnsWeak); | |
| 65 } | |
| 66 | |
| 67 nsresult RemoveWeakElement(T *aElement) | |
| 68 { | |
| 69 return NS_RemoveWeakElementBase( | |
| 70 reinterpret_cast<isupports_array_type*>(this), aElement); | |
| 71 } | |
| 72 }; | |
| 73 | |
| 74 template <typename T> | |
| 75 inline void | |
| 76 ImplCycleCollectionUnlink(nsMaybeWeakPtrArray<T>& aField) | |
| 77 { | |
| 78 aField.Clear(); | |
| 79 } | |
| 80 | |
| 81 template <typename E> | |
| 82 inline void | |
| 83 ImplCycleCollectionTraverse(nsCycleCollectionTraversalCallback& aCallback, | |
| 84 nsMaybeWeakPtrArray<E>& aField, | |
| 85 const char* aName, | |
| 86 uint32_t aFlags = 0) | |
| 87 { | |
| 88 aFlags |= CycleCollectionEdgeNameArrayFlag; | |
| 89 size_t length = aField.Length(); | |
| 90 for (size_t i = 0; i < length; ++i) { | |
| 91 CycleCollectionNoteChild(aCallback, aField[i].get(), aName, aFlags); | |
| 92 } | |
| 93 } | |
| 94 | |
| 95 // Call a method on each element in the array, but only if the element is | |
| 96 // non-null. | |
| 97 | |
| 98 #define ENUMERATE_WEAKARRAY(array, type, method) \ | |
| 99 for (uint32_t array_idx = 0; array_idx < array.Length(); ++array_idx) { \ | |
| 100 const nsCOMPtr<type> &e = array.ElementAt(array_idx); \ | |
| 101 if (e) \ | |
| 102 e->method; \ | |
| 103 } | |
| 104 | |
| 105 #endif |
