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
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
|
#if NET_4_0 || BOOTSTRAP_NET_4_0
//
// CancellationTokenSource.cs
//
// Author:
// Jérémie "Garuma" Laval <jeremie.laval@gmail.com>
//
// Copyright (c) 2009 Jérémie "Garuma" Laval
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
using System;
using System.Collections.Generic;
namespace System.Threading
{
public class CancellationTokenSource : IDisposable, ICancelableOperation
{
volatile bool canceled;
volatile bool processed;
int currId = int.MinValue;
Dictionary<CancellationTokenRegistration, Action> callbacks
= new Dictionary<CancellationTokenRegistration, Action> ();
ManualResetEvent handle = new ManualResetEvent (false);
//#if USE_MONITOR
object syncRoot = new object ();
//#endif
public void Cancel ()
{
Cancel (false);
}
// If parameter is true we throw exception as soon as they appear otherwise we aggregate them
public void Cancel (bool throwOnFirst)
{
canceled = true;
handle.Set ();
List<Exception> exceptions = null;
if (!throwOnFirst)
exceptions = new List<Exception> ();
lock (callbacks) {
foreach (KeyValuePair<CancellationTokenRegistration, Action> item in callbacks) {
if (throwOnFirst) {
item.Value ();
} else {
try {
item.Value ();
} catch (Exception e) {
exceptions.Add (e);
}
}
}
}
processed = true;
if (exceptions != null && exceptions.Count > 0)
throw new AggregateException (exceptions);
}
public void Dispose ()
{
}
public static CancellationTokenSource CreateLinkedTokenSource (CancellationToken token1, CancellationToken token2)
{
return CreateLinkedTokenSource (new CancellationToken[] { token1, token2 });
}
public static CancellationTokenSource CreateLinkedTokenSource (params CancellationToken[] tokens)
{
CancellationTokenSource src = new CancellationTokenSource ();
Action action = src.Cancel;
foreach (CancellationToken token in tokens)
token.Register (action);
return src;
}
public CancellationToken Token {
get {
CancellationToken token = new CancellationToken (canceled);
token.Source = this;
return token;
}
}
public bool IsCancellationRequested {
get {
return canceled;
}
}
internal WaitHandle WaitHandle {
get {
return handle;
}
}
internal CancellationTokenRegistration Register (Action callback, bool useSynchronizationContext)
{
CancellationTokenRegistration tokenReg = GetTokenReg ();
if (canceled) {
callback ();
} else {
bool temp = false;
lock (syncRoot) {
if (!(temp = canceled))
callbacks.Add (tokenReg, callback);
}
if (temp)
callback ();
}
return tokenReg;
}
internal void RemoveCallback (CancellationTokenRegistration tokenReg)
{
if (!canceled) {
lock (syncRoot) {
if (!canceled) {
callbacks.Remove (tokenReg);
return;
}
}
}
SpinWait sw = new SpinWait ();
while (!processed)
sw.SpinOnce ();
}
CancellationTokenRegistration GetTokenReg ()
{
CancellationTokenRegistration registration
= new CancellationTokenRegistration (Interlocked.Increment (ref currId), this);
return registration;
}
}
}
#endif
|
