xpcom/ds/nsHashtablesFwd.h

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #ifndef XPCOM_DS_NSHASHTABLESFWD_H_
   8 #define XPCOM_DS_NSHASHTABLESFWD_H_
   9
  10 #include "mozilla/Attributes.h"
  11
  12 struct PLDHashEntryHdr;
  13
  14 template <class T>
  15 class MOZ_IS_REFPTR nsCOMPtr;
  16
  17 template <class T>
  18 class MOZ_IS_REFPTR RefPtr;
  19
  20 template <class EntryType>
  21 class MOZ_NEEDS_NO_VTABLE_TYPE nsTHashtable;
  22
  23 template <class DataType, class UserDataType>
  24 class nsDefaultConverter;
  25
  26 template <class KeyClass, class DataType, class UserDataType,
  27           class Converter = nsDefaultConverter<DataType, UserDataType>>
  28 class nsBaseHashtable;
  29
  30 template <class KeyClass, class T>
  31 class nsClassHashtable;
  32
  33 template <class KeyClass, class PtrType>
  34 class nsRefCountedHashtable;
  35
  36 /**
  37  * templated hashtable class maps keys to interface pointers.
  38  * See nsBaseHashtable for complete declaration.
  39  * @deprecated This is going to be removed. Use nsTHashMap instead.
  40  * @param KeyClass a wrapper-class for the hashtable key, see nsHashKeys.h
  41  *   for a complete specification.
  42  * @param Interface the interface-type being wrapped
  43  * @see nsClassHashtable, nsTHashMap
  44  */
  45 template <class KeyClass, class Interface>
  46 using nsInterfaceHashtable =
  47     nsRefCountedHashtable<KeyClass, nsCOMPtr<Interface>>;
  48
  49 /**
  50  * templated hashtable class maps keys to reference pointers.
  51  * See nsBaseHashtable for complete declaration.
  52  * @deprecated This is going to be removed. Use nsTHashMap instead.
  53  * @param KeyClass a wrapper-class for the hashtable key, see nsHashKeys.h
  54  *   for a complete specification.
  55  * @param PtrType the reference-type being wrapped
  56  * @see nsClassHashtable, nsTHashMap
  57  */
  58 template <class KeyClass, class ClassType>
  59 using nsRefPtrHashtable = nsRefCountedHashtable<KeyClass, RefPtr<ClassType>>;
  60
  61 namespace mozilla::detail {
  62 template <class KeyType, class = void>
  63 struct nsKeyClass;
  64 }  // namespace mozilla::detail
  65
  66 /**
  67  * A universal hash map that maps some KeyType to some DataType. It can be used
  68  * for any DataType, including RefPtr<T>, nsCOMPtr<T> and UniquePtr<T>.
  69  *
  70  * For the default hash keys types, the appropriate hash key class is determined
  71  * automatically, so you can just specify `nsTHashMap<uint32_t,
  72  * RefPtr<Foo>>`, for example.
  73  *
  74  * If you require custom hash behaviour (e.g. case insensitive string handling),
  75  * you can still specify a hash key class derived from PLDHashEntryHdr
  76  * explicitly.
  77  *
  78  * If you need to use a custom UserDataType, use nsBaseHashtable (or
  79  * nsTHashtable) directly. However, you should double-check if that's really
  80  * necessary.
  81  */
  82 template <class KeyType, class DataType>
  83 using nsTHashMap =
  84     nsBaseHashtable<typename mozilla::detail::nsKeyClass<KeyType>::type,
  85                     DataType, DataType>;
  86
  87 template <class KeyClass>
  88 class nsTBaseHashSet;
  89
  90 template <class KeyType>
  91 using nsTHashSet =
  92     nsTBaseHashSet<typename mozilla::detail::nsKeyClass<KeyType>::type>;
  93
  94 #endif  // XPCOM_DS_NSHASHTABLESFWD_H_