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
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
| #include <windows.h>
#include <tchar.h>
#include <stdio.h>
//
// Thread pool wait callback function template
//
VOID
CALLBACK
MyWaitCallback(
PTP_CALLBACK_INSTANCE Instance,
PVOID Parameter,
PTP_WAIT Wait,
TP_WAIT_RESULT WaitResult
)
{
//
// Do something when the wait is over.
//
_tprintf(_T("MyWaitCallback: wait is over.\n"));
}
//
// Thread pool timer callback function template
//
VOID
CALLBACK
MyTimerCallback(
PTP_CALLBACK_INSTANCE Instance,
PVOID Parameter,
PTP_TIMER Timer
)
{
//
// Do something when the timer fires.
//
_tprintf(_T("MyTimerCallback: timer has fired.\n"));
}
//
// This is the thread pool work callback function.
// The callback demonstrates correct behavior when changing the
// state of the thread inside the callback function.
//
// Any changes to the thread state must be restored to original
// before exiting the callback routine.
//
VOID
CALLBACK
MyWorkCallback(
PTP_CALLBACK_INSTANCE Instance,
PVOID Parameter,
PTP_WORK Work
)
{
BOOL bRet = FALSE;
DWORD dwPriorityOriginal = 0;
//
// Record the original thread priority.
//
dwPriorityOriginal = GetThreadPriority(GetCurrentThread());
if (THREAD_PRIORITY_ERROR_RETURN == dwPriorityOriginal) {
_tprintf(_T("GetThreadPriority failed. LastError: %u\n"),
GetLastError());
return;
}
//
// Increase the priority of the thread pool thread.
//
bRet = SetThreadPriority(GetCurrentThread(),
THREAD_PRIORITY_ABOVE_NORMAL);
if (FALSE == bRet) {
_tprintf(_T("SetThreadPriority failed. LastError: %u\n"),
GetLastError());
return;
}
_tprintf(_T("MyWorkCallback: thread priority increased.\n"));
//
// Perform tasks at increased priority.
//
{
_tprintf(_T("MyWorkCallback: task performed at increased priority.\n"));
}
//
// Restore thread state by resetting the original priority.
//
bRet = SetThreadPriority(GetCurrentThread(),
dwPriorityOriginal);
//
// If restore fails, maybe retry or throw an exception. Otherwise,
// the thread will continue to execute other work items at increased
// priority.
//
if (FALSE == bRet) {
_tprintf(_T("Fatal Error! SetThreadPriority failed. LastError: %u\n"),
GetLastError());
return;
}
_tprintf(_T("MyWorkCallback: thread priority restored.\n"));
return;
}
VOID
DemoCleanupPersistentWorkTimer()
{
BOOL bRet = FALSE;
PTP_WORK work = NULL;
PTP_TIMER timer = NULL;
PTP_POOL pool = NULL;
PTP_WORK_CALLBACK workcallback = MyWorkCallback;
PTP_TIMER_CALLBACK timercallback = MyTimerCallback;
TP_CALLBACK_ENVIRON CallBackEnviron;
PTP_CLEANUP_GROUP cleanupgroup = NULL;
FILETIME FileDueTime;
ULARGE_INTEGER ulDueTime;
UINT rollback = 0;
InitializeThreadpoolEnvironment(&CallBackEnviron);
//
// Create a custom, dedicated thread pool.
//
pool = CreateThreadpool(NULL);
if (NULL == pool) {
_tprintf(_T("CreateThreadpool failed. LastError: %u\n"),
GetLastError());
goto main_cleanup;
}
rollback = 1; // pool creation succeeded
//
// The thread pool is made persistent simply by setting
// both the minimum and maximum threads to 1.
//
SetThreadpoolThreadMaximum(pool, 1);
bRet = SetThreadpoolThreadMinimum(pool, 1);
if (FALSE == bRet) {
_tprintf(_T("SetThreadpoolThreadMinimum failed. LastError: %u\n"),
GetLastError());
goto main_cleanup;
}
//
// Create a cleanup group for this thread pool.
//
cleanupgroup = CreateThreadpoolCleanupGroup();
if (NULL == cleanupgroup) {
_tprintf(_T("CreateThreadpoolCleanupGroup failed. LastError: %u\n"),
GetLastError());
goto main_cleanup;
}
rollback = 2; // Cleanup group creation succeeded
//
// Associate the callback environment with our thread pool.
//
SetThreadpoolCallbackPool(&CallBackEnviron, pool);
//
// Associate the cleanup group with our thread pool.
// Objects created with the same callback environment
// as the cleanup group become members of the cleanup group.
//
SetThreadpoolCallbackCleanupGroup(&CallBackEnviron,
cleanupgroup,
NULL);
//
// Create work with the callback environment.
//
work = CreateThreadpoolWork(workcallback,
NULL,
&CallBackEnviron);
if (NULL == work) {
_tprintf(_T("CreateThreadpoolWork failed. LastError: %u\n"),
GetLastError());
goto main_cleanup;
}
rollback = 3; // Creation of work succeeded
//
// Submit the work to the pool. Because this was a pre-allocated
// work item (using CreateThreadpoolWork), it is guaranteed to execute.
//
SubmitThreadpoolWork(work);
//
// Create a timer with the same callback environment.
//
timer = CreateThreadpoolTimer(timercallback,
NULL,
&CallBackEnviron);
if (NULL == timer) {
_tprintf(_T("CreateThreadpoolTimer failed. LastError: %u\n"),
GetLastError());
goto main_cleanup;
}
rollback = 4; // Timer creation succeeded
//
// Set the timer to fire in one second.
//
ulDueTime.QuadPart = (LONGLONG) -(1 * 10 * 1000 * 1000);
FileDueTime.dwHighDateTime = ulDueTime.HighPart;
FileDueTime.dwLowDateTime = ulDueTime.LowPart;
SetThreadpoolTimer(timer,
&FileDueTime,
0,
0);
//
// Delay for the timer to be fired
//
Sleep(1500);
//
// Wait for all callbacks to finish.
// CloseThreadpoolCleanupGroupMembers also releases objects
// that are members of the cleanup group, so it is not necessary
// to call close functions on individual objects
// after calling CloseThreadpoolCleanupGroupMembers.
//
CloseThreadpoolCleanupGroupMembers(cleanupgroup,
FALSE,
NULL);
//
// Already cleaned up the work item with the
// CloseThreadpoolCleanupGroupMembers, so set rollback to 2.
//
rollback = 2;
goto main_cleanup;
main_cleanup:
//
// Clean up any individual pieces manually
// Notice the fall-through structure of the switch.
// Clean up in reverse order.
//
switch (rollback) {
case 4:
case 3:
// Clean up the cleanup group members.
CloseThreadpoolCleanupGroupMembers(cleanupgroup,
FALSE, NULL);
case 2:
// Clean up the cleanup group.
CloseThreadpoolCleanupGroup(cleanupgroup);
case 1:
// Clean up the pool.
CloseThreadpool(pool);
default:
break;
}
return;
}
VOID
DemoNewRegisterWait()
{
PTP_WAIT Wait = NULL;
PTP_WAIT_CALLBACK waitcallback = MyWaitCallback;
HANDLE hEvent = NULL;
UINT i = 0;
UINT rollback = 0;
//
// Create an auto-reset event.
//
hEvent = CreateEvent(NULL, FALSE, FALSE, NULL);
if (NULL == hEvent) {
// Error Handling
return;
}
rollback = 1; // CreateEvent succeeded
Wait = CreateThreadpoolWait(waitcallback,
NULL,
NULL);
if(NULL == Wait) {
_tprintf(_T("CreateThreadpoolWait failed. LastError: %u\n"),
GetLastError());
goto new_wait_cleanup;
}
rollback = 2; // CreateThreadpoolWait succeeded
//
// Need to re-register the event with the wait object
// each time before signaling the event to trigger the wait callback.
//
for (i = 0; i < 5; i ++) {
SetThreadpoolWait(Wait,
hEvent,
NULL);
SetEvent(hEvent);
//
// Delay for the waiter thread to act if necessary.
//
Sleep(500);
//
// Block here until the callback function is done executing.
//
WaitForThreadpoolWaitCallbacks(Wait, FALSE);
}
new_wait_cleanup:
switch (rollback) {
case 2:
// Unregister the wait by setting the event to NULL.
SetThreadpoolWait(Wait, NULL, NULL);
// Close the wait.
CloseThreadpoolWait(Wait);
case 1:
// Close the event.
CloseHandle(hEvent);
default:
break;
}
return;
}
int _tmain(int argc, _TCHAR* argv[])
{
DemoNewRegisterWait();
DemoCleanupPersistentWorkTimer();
return 0;
}
|