1 /*
2  *  Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
3  *
4  *  Use of this source code is governed by a BSD-style license
5  *  that can be found in the LICENSE file in the root of the source
6  *  tree. An additional intellectual property rights grant can be found
7  *  in the file PATENTS.  All contributing project authors may
8  *  be found in the AUTHORS file in the root of the source tree.
9  */
10 
11 #ifndef WEBRTC_SYSTEM_WRAPPERS_INTERFACE_LIST_WRAPPER_H_
12 #define WEBRTC_SYSTEM_WRAPPERS_INTERFACE_LIST_WRAPPER_H_
13 
14 #include "constructor_magic.h"
15 
16 namespace webrtc {
17 class CriticalSectionWrapper;
18 
19 class ListItem
20 {
21 friend class ListWrapper;
22 
23 public:
24     ListItem(const void* ptr);
25     ListItem(const unsigned int item);
26     virtual ~ListItem();
27     void* GetItem() const;
28     unsigned int GetUnsignedItem() const;
29 
30 protected:
31     ListItem* next_;
32     ListItem* prev_;
33 
34 private:
35     const void*         item_ptr_;
36     const unsigned int  item_;
37 };
38 
39 class ListWrapper
40 {
41 public:
42     ListWrapper();
43     virtual ~ListWrapper();
44 
45     // Returns the number of elements stored in the list.
46     unsigned int GetSize() const;
47 
48     // Puts a pointer to anything last in the list.
49     int PushBack(const void* ptr);
50     // Puts a pointer to anything first in the list.
51     int PushFront(const void* ptr);
52 
53     // Puts a copy of the specified integer last in the list.
54     int PushBack(const unsigned int item_id);
55     // Puts a copy of the specified integer first in the list.
56     int PushFront(const unsigned int item_id);
57 
58     // Pops the first ListItem from the list
59     int PopFront();
60 
61     // Pops the last ListItem from the list
62     int PopBack();
63 
64     // Returns true if the list is empty
65     bool Empty() const;
66 
67     // Returns a pointer to the first ListItem in the list.
68     ListItem* First() const;
69 
70     // Returns a pointer to the last ListItem in the list.
71     ListItem* Last() const;
72 
73     // Returns a pointer to the ListItem stored after item in the list.
74     ListItem* Next(ListItem* item) const;
75 
76     // Returns a pointer to the ListItem stored before item in the list.
77     ListItem* Previous(ListItem* item) const;
78 
79     // Removes item from the list.
80     int Erase(ListItem* item);
81 
82     // Insert list item after existing_previous_item. Please note that new_item
83     // must be created using new ListItem(). The map will take ownership of
84     // new_item following a successfull insert. If insert fails new_item will
85     // not be released by the List
86     int Insert(ListItem* existing_previous_item,
87                ListItem* new_item);
88 
89     // Insert list item before existing_next_item. Please note that new_item
90     // must be created using new ListItem(). The map will take ownership of
91     // new_item following a successfull insert. If insert fails new_item will
92     // not be released by the List
93     int InsertBefore(ListItem* existing_next_item,
94                      ListItem* new_item);
95 
96 private:
97     void PushBackImpl(ListItem* item);
98     void PushFrontImpl(ListItem* item);
99 
100     CriticalSectionWrapper* critical_section_;
101     ListItem* first_;
102     ListItem* last_;
103     unsigned int size_;
104 };
105 } //namespace webrtc
106 
107 #endif // WEBRTC_SYSTEM_WRAPPERS_INTERFACE_LIST_WRAPPER_H_
108