1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
|
/* -*- 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 nsInterfaceHashtable_h__
#define nsInterfaceHashtable_h__
#include "nsBaseHashtable.h"
#include "nsHashKeys.h"
#include "nsCOMPtr.h"
/**
* templated hashtable class maps keys to interface pointers.
* See nsBaseHashtable for complete declaration.
* @param KeyClass a wrapper-class for the hashtable key, see nsHashKeys.h
* for a complete specification.
* @param Interface the interface-type being wrapped
* @see nsDataHashtable, nsClassHashtable
*/
template<class KeyClass, class Interface>
class nsInterfaceHashtable
: public nsBaseHashtable<KeyClass, nsCOMPtr<Interface>, Interface*>
{
public:
typedef typename KeyClass::KeyType KeyType;
typedef Interface* UserDataType;
typedef nsBaseHashtable<KeyClass, nsCOMPtr<Interface>, Interface*> base_type;
nsInterfaceHashtable() {}
explicit nsInterfaceHashtable(uint32_t aInitLength)
: nsBaseHashtable<KeyClass, nsCOMPtr<Interface>, Interface*>(aInitLength)
{
}
/**
* @copydoc nsBaseHashtable::Get
* @param aData This is an XPCOM getter, so aData is already_addrefed.
* If the key doesn't exist, aData will be set to nullptr.
*/
bool Get(KeyType aKey, UserDataType* aData) const;
/**
* @copydoc nsBaseHashtable::Get
*/
already_AddRefed<Interface> Get(KeyType aKey) const;
/**
* Gets a weak reference to the hashtable entry.
* @param aFound If not nullptr, will be set to true if the entry is found,
* to false otherwise.
* @return The entry, or nullptr if not found. Do not release this pointer!
*/
Interface* GetWeak(KeyType aKey, bool* aFound = nullptr) const;
};
template<typename K, typename T>
inline void
ImplCycleCollectionUnlink(nsInterfaceHashtable<K, T>& aField)
{
aField.Clear();
}
template<typename K, typename T>
inline void
ImplCycleCollectionTraverse(nsCycleCollectionTraversalCallback& aCallback,
const nsInterfaceHashtable<K, T>& aField,
const char* aName,
uint32_t aFlags = 0)
{
for (auto iter = aField.ConstIter(); !iter.Done(); iter.Next()) {
CycleCollectionNoteChild(aCallback, iter.UserData(), aName, aFlags);
}
}
//
// nsInterfaceHashtable definitions
//
template<class KeyClass, class Interface>
bool
nsInterfaceHashtable<KeyClass, Interface>::Get(KeyType aKey,
UserDataType* aInterface) const
{
typename base_type::EntryType* ent = this->GetEntry(aKey);
if (ent) {
if (aInterface) {
*aInterface = ent->mData;
NS_IF_ADDREF(*aInterface);
}
return true;
}
// if the key doesn't exist, set *aInterface to null
// so that it is a valid XPCOM getter
if (aInterface) {
*aInterface = nullptr;
}
return false;
}
template<class KeyClass, class Interface>
already_AddRefed<Interface>
nsInterfaceHashtable<KeyClass, Interface>::Get(KeyType aKey) const
{
typename base_type::EntryType* ent = this->GetEntry(aKey);
if (!ent) {
return nullptr;
}
nsCOMPtr<Interface> copy = ent->mData;
return copy.forget();
}
template<class KeyClass, class Interface>
Interface*
nsInterfaceHashtable<KeyClass, Interface>::GetWeak(KeyType aKey,
bool* aFound) const
{
typename base_type::EntryType* ent = this->GetEntry(aKey);
if (ent) {
if (aFound) {
*aFound = true;
}
return ent->mData;
}
// Key does not exist, return nullptr and set aFound to false
if (aFound) {
*aFound = false;
}
return nullptr;
}
#endif // nsInterfaceHashtable_h__
|