mfbt/EnumeratedArray.h@97036ab72558 (annotated)
mfbt/EnumeratedArray.h
Tue, 06 Jan 2015 21:39:09 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Tue, 06 Jan 2015 21:39:09 +0100
- branch
- TOR_BUG_9701
- changeset 8
- 97036ab72558
- permissions
- -rw-r--r--
Conditionally force memory storage according to privacy.thirdparty.isolate;
This solves Tor bug #9701, complying with disk avoidance documented in
https://www.torproject.org/projects/torbrowser/design/#disk-avoidance.
| michael@0 | 1 | /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ |
| michael@0 | 2 | /* vim: set ts=8 sts=2 et sw=2 tw=80: */ |
| michael@0 | 3 | /* This Source Code Form is subject to the terms of the Mozilla Public |
| michael@0 | 4 | * License, v. 2.0. If a copy of the MPL was not distributed with this |
| michael@0 | 5 | * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ |
| michael@0 | 6 | |
| michael@0 | 7 | /* EnumeratedArray is like Array, but indexed by a typed enum. */ |
| michael@0 | 8 | |
| michael@0 | 9 | #ifndef mozilla_EnumeratedArray_h |
| michael@0 | 10 | #define mozilla_EnumeratedArray_h |
| michael@0 | 11 | |
| michael@0 | 12 | #include "mozilla/Array.h" |
| michael@0 | 13 | #include "mozilla/TypedEnum.h" |
| michael@0 | 14 | |
| michael@0 | 15 | namespace mozilla { |
| michael@0 | 16 | |
| michael@0 | 17 | /** |
| michael@0 | 18 | * EnumeratedArray is a fixed-size array container for use when an |
| michael@0 | 19 | * array is indexed by a specific enum class, as currently implemented |
| michael@0 | 20 | * by MOZ_BEGIN_ENUM_CLASS. |
| michael@0 | 21 | * |
| michael@0 | 22 | * This provides type safety by guarding at compile time against accidentally |
| michael@0 | 23 | * indexing such arrays with unrelated values. This also removes the need |
| michael@0 | 24 | * for manual casting when using a typed enum value to index arrays. |
| michael@0 | 25 | * |
| michael@0 | 26 | * Aside from the typing of indices, EnumeratedArray is similar to Array. |
| michael@0 | 27 | * |
| michael@0 | 28 | * Example: |
| michael@0 | 29 | * |
| michael@0 | 30 | * MOZ_BEGIN_ENUM_CLASS(AnimalSpecies) |
| michael@0 | 31 | * Cow, |
| michael@0 | 32 | * Sheep, |
| michael@0 | 33 | * Count |
| michael@0 | 34 | * MOZ_END_ENUM_CLASS(AnimalSpecies) |
| michael@0 | 35 | * |
| michael@0 | 36 | * EnumeratedArray<AnimalSpecies, AnimalSpecies::Count, int> headCount; |
| michael@0 | 37 | * |
| michael@0 | 38 | * headCount[AnimalSpecies::Cow] = 17; |
| michael@0 | 39 | * headCount[AnimalSpecies::Sheep] = 30; |
| michael@0 | 40 | * |
| michael@0 | 41 | */ |
| michael@0 | 42 | template<typename IndexType, |
| michael@0 | 43 | MOZ_TEMPLATE_ENUM_CLASS_ENUM_TYPE(IndexType) SizeAsEnumValue, |
| michael@0 | 44 | typename ValueType> |
| michael@0 | 45 | class EnumeratedArray |
| michael@0 | 46 | { |
| michael@0 | 47 | public: |
| michael@0 | 48 | static const size_t Size = size_t(SizeAsEnumValue); |
| michael@0 | 49 | |
| michael@0 | 50 | private: |
| michael@0 | 51 | Array<ValueType, Size> mArray; |
| michael@0 | 52 | |
| michael@0 | 53 | public: |
| michael@0 | 54 | EnumeratedArray() {} |
| michael@0 | 55 | |
| michael@0 | 56 | explicit EnumeratedArray(const EnumeratedArray& aOther) |
| michael@0 | 57 | { |
| michael@0 | 58 | for (size_t i = 0; i < Size; i++) |
| michael@0 | 59 | mArray[i] = aOther.mArray[i]; |
| michael@0 | 60 | } |
| michael@0 | 61 | |
| michael@0 | 62 | explicit EnumeratedArray(const ValueType (&aOther)[Size]) |
| michael@0 | 63 | { |
| michael@0 | 64 | for (size_t i = 0; i < Size; i++) |
| michael@0 | 65 | mArray[i] = aOther[i]; |
| michael@0 | 66 | } |
| michael@0 | 67 | |
| michael@0 | 68 | ValueType& operator[](IndexType aIndex) |
| michael@0 | 69 | { |
| michael@0 | 70 | return mArray[size_t(aIndex)]; |
| michael@0 | 71 | } |
| michael@0 | 72 | |
| michael@0 | 73 | const ValueType& operator[](IndexType aIndex) const |
| michael@0 | 74 | { |
| michael@0 | 75 | return mArray[size_t(aIndex)]; |
| michael@0 | 76 | } |
| michael@0 | 77 | }; |
| michael@0 | 78 | |
| michael@0 | 79 | } // namespace mozilla |
| michael@0 | 80 | |
| michael@0 | 81 | #endif // mozilla_EnumeratedArray_h |
