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author | David Walter Seikel | 2016-11-03 21:44:39 +1000 |
---|---|---|
committer | David Walter Seikel | 2016-11-03 21:44:39 +1000 |
commit | 134f86e8d5c414409631b25b8c6f0ee45fbd8631 (patch) | |
tree | 216b89d3fb89acfb81be1e440c25c41ab09fa96d /OpenSim/Framework/RestClient.cs | |
parent | More changing to production grid. Double oops. (diff) | |
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Initial update to OpenSim 0.8.2.1 source code.
Diffstat (limited to 'OpenSim/Framework/RestClient.cs')
-rw-r--r-- | OpenSim/Framework/RestClient.cs | 676 |
1 files changed, 676 insertions, 0 deletions
diff --git a/OpenSim/Framework/RestClient.cs b/OpenSim/Framework/RestClient.cs new file mode 100644 index 0000000..7080ca5 --- /dev/null +++ b/OpenSim/Framework/RestClient.cs | |||
@@ -0,0 +1,676 @@ | |||
1 | /* | ||
2 | * Copyright (c) Contributors, http://opensimulator.org/ | ||
3 | * See CONTRIBUTORS.TXT for a full list of copyright holders. | ||
4 | * | ||
5 | * Redistribution and use in source and binary forms, with or without | ||
6 | * modification, are permitted provided that the following conditions are met: | ||
7 | * * Redistributions of source code must retain the above copyright | ||
8 | * notice, this list of conditions and the following disclaimer. | ||
9 | * * Redistributions in binary form must reproduce the above copyright | ||
10 | * notice, this list of conditions and the following disclaimer in the | ||
11 | * documentation and/or other materials provided with the distribution. | ||
12 | * * Neither the name of the OpenSimulator Project nor the | ||
13 | * names of its contributors may be used to endorse or promote products | ||
14 | * derived from this software without specific prior written permission. | ||
15 | * | ||
16 | * THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY | ||
17 | * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED | ||
18 | * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE | ||
19 | * DISCLAIMED. IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE FOR ANY | ||
20 | * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES | ||
21 | * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; | ||
22 | * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND | ||
23 | * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT | ||
24 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS | ||
25 | * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. | ||
26 | */ | ||
27 | |||
28 | using System; | ||
29 | using System.Collections.Generic; | ||
30 | using System.IO; | ||
31 | using System.Net; | ||
32 | using System.Reflection; | ||
33 | using System.Text; | ||
34 | using System.Threading; | ||
35 | using System.Web; | ||
36 | using log4net; | ||
37 | |||
38 | using OpenSim.Framework.ServiceAuth; | ||
39 | |||
40 | namespace OpenSim.Framework | ||
41 | { | ||
42 | /// <summary> | ||
43 | /// Implementation of a generic REST client | ||
44 | /// </summary> | ||
45 | /// <remarks> | ||
46 | /// This class is a generic implementation of a REST (Representational State Transfer) web service. This | ||
47 | /// class is designed to execute both synchronously and asynchronously. | ||
48 | /// | ||
49 | /// Internally the implementation works as a two stage asynchronous web-client. | ||
50 | /// When the request is initiated, RestClient will query asynchronously for for a web-response, | ||
51 | /// sleeping until the initial response is returned by the server. Once the initial response is retrieved | ||
52 | /// the second stage of asynchronous requests will be triggered, in an attempt to read of the response | ||
53 | /// object into a memorystream as a sequence of asynchronous reads. | ||
54 | /// | ||
55 | /// The asynchronisity of RestClient is designed to move as much processing into the back-ground, allowing | ||
56 | /// other threads to execute, while it waits for a response from the web-service. RestClient itself can be | ||
57 | /// invoked by the caller in either synchronous mode or asynchronous modes. | ||
58 | /// </remarks> | ||
59 | public class RestClient : IDisposable | ||
60 | { | ||
61 | private static readonly ILog m_log = LogManager.GetLogger(MethodBase.GetCurrentMethod().DeclaringType); | ||
62 | |||
63 | // private string realuri; | ||
64 | |||
65 | #region member variables | ||
66 | |||
67 | /// <summary> | ||
68 | /// The base Uri of the web-service e.g. http://www.google.com | ||
69 | /// </summary> | ||
70 | private string _url; | ||
71 | |||
72 | /// <summary> | ||
73 | /// Path elements of the query | ||
74 | /// </summary> | ||
75 | private List<string> _pathElements = new List<string>(); | ||
76 | |||
77 | /// <summary> | ||
78 | /// Parameter elements of the query, e.g. min=34 | ||
79 | /// </summary> | ||
80 | private Dictionary<string, string> _parameterElements = new Dictionary<string, string>(); | ||
81 | |||
82 | /// <summary> | ||
83 | /// Request method. E.g. GET, POST, PUT or DELETE | ||
84 | /// </summary> | ||
85 | private string _method; | ||
86 | |||
87 | /// <summary> | ||
88 | /// Temporary buffer used to store bytes temporarily as they come in from the server | ||
89 | /// </summary> | ||
90 | private byte[] _readbuf; | ||
91 | |||
92 | /// <summary> | ||
93 | /// MemoryStream representing the resulting resource | ||
94 | /// </summary> | ||
95 | private Stream _resource; | ||
96 | |||
97 | /// <summary> | ||
98 | /// WebRequest object, held as a member variable | ||
99 | /// </summary> | ||
100 | private HttpWebRequest _request; | ||
101 | |||
102 | /// <summary> | ||
103 | /// WebResponse object, held as a member variable, so we can close it | ||
104 | /// </summary> | ||
105 | private HttpWebResponse _response; | ||
106 | |||
107 | /// <summary> | ||
108 | /// This flag will help block the main synchroneous method, in case we run in synchroneous mode | ||
109 | /// </summary> | ||
110 | //public static ManualResetEvent _allDone = new ManualResetEvent(false); | ||
111 | |||
112 | /// <summary> | ||
113 | /// Default time out period | ||
114 | /// </summary> | ||
115 | //private const int DefaultTimeout = 10*1000; // 10 seconds timeout | ||
116 | |||
117 | /// <summary> | ||
118 | /// Default Buffer size of a block requested from the web-server | ||
119 | /// </summary> | ||
120 | private const int BufferSize = 4096; // Read blocks of 4 KB. | ||
121 | |||
122 | |||
123 | /// <summary> | ||
124 | /// if an exception occours during async processing, we need to save it, so it can be | ||
125 | /// rethrown on the primary thread; | ||
126 | /// </summary> | ||
127 | private Exception _asyncException; | ||
128 | |||
129 | #endregion member variables | ||
130 | |||
131 | #region constructors | ||
132 | |||
133 | /// <summary> | ||
134 | /// Instantiate a new RestClient | ||
135 | /// </summary> | ||
136 | /// <param name="url">Web-service to query, e.g. http://osgrid.org:8003</param> | ||
137 | public RestClient(string url) | ||
138 | { | ||
139 | _url = url; | ||
140 | _readbuf = new byte[BufferSize]; | ||
141 | _resource = new MemoryStream(); | ||
142 | _request = null; | ||
143 | _response = null; | ||
144 | _lock = new object(); | ||
145 | } | ||
146 | |||
147 | private object _lock; | ||
148 | |||
149 | #endregion constructors | ||
150 | |||
151 | |||
152 | #region Dispose | ||
153 | |||
154 | private bool disposed = false; | ||
155 | |||
156 | public void Dispose() | ||
157 | { | ||
158 | Dispose(true); | ||
159 | GC.SuppressFinalize(this); | ||
160 | } | ||
161 | |||
162 | protected virtual void Dispose(bool disposing) | ||
163 | { | ||
164 | if (disposed) | ||
165 | return; | ||
166 | |||
167 | if (disposing) | ||
168 | { | ||
169 | _resource.Dispose(); | ||
170 | } | ||
171 | |||
172 | disposed = true; | ||
173 | } | ||
174 | |||
175 | #endregion Dispose | ||
176 | |||
177 | |||
178 | /// <summary> | ||
179 | /// Add a path element to the query, e.g. assets | ||
180 | /// </summary> | ||
181 | /// <param name="element">path entry</param> | ||
182 | public void AddResourcePath(string element) | ||
183 | { | ||
184 | if (isSlashed(element)) | ||
185 | _pathElements.Add(element.Substring(0, element.Length - 1)); | ||
186 | else | ||
187 | _pathElements.Add(element); | ||
188 | } | ||
189 | |||
190 | /// <summary> | ||
191 | /// Add a query parameter to the Url | ||
192 | /// </summary> | ||
193 | /// <param name="name">Name of the parameter, e.g. min</param> | ||
194 | /// <param name="value">Value of the parameter, e.g. 42</param> | ||
195 | public void AddQueryParameter(string name, string value) | ||
196 | { | ||
197 | try | ||
198 | { | ||
199 | _parameterElements.Add(HttpUtility.UrlEncode(name), HttpUtility.UrlEncode(value)); | ||
200 | } | ||
201 | catch (ArgumentException) | ||
202 | { | ||
203 | m_log.Error("[REST]: Query parameter " + name + " is already added."); | ||
204 | } | ||
205 | catch (Exception e) | ||
206 | { | ||
207 | m_log.Error("[REST]: An exception was raised adding query parameter to dictionary. Exception: {0}",e); | ||
208 | } | ||
209 | } | ||
210 | |||
211 | /// <summary> | ||
212 | /// Add a query parameter to the Url | ||
213 | /// </summary> | ||
214 | /// <param name="name">Name of the parameter, e.g. min</param> | ||
215 | public void AddQueryParameter(string name) | ||
216 | { | ||
217 | try | ||
218 | { | ||
219 | _parameterElements.Add(HttpUtility.UrlEncode(name), null); | ||
220 | } | ||
221 | catch (ArgumentException) | ||
222 | { | ||
223 | m_log.Error("[REST]: Query parameter " + name + " is already added."); | ||
224 | } | ||
225 | catch (Exception e) | ||
226 | { | ||
227 | m_log.Error("[REST]: An exception was raised adding query parameter to dictionary. Exception: {0}",e); | ||
228 | } | ||
229 | } | ||
230 | |||
231 | /// <summary> | ||
232 | /// Web-Request method, e.g. GET, PUT, POST, DELETE | ||
233 | /// </summary> | ||
234 | public string RequestMethod | ||
235 | { | ||
236 | get { return _method; } | ||
237 | set { _method = value; } | ||
238 | } | ||
239 | |||
240 | /// <summary> | ||
241 | /// True if string contains a trailing slash '/' | ||
242 | /// </summary> | ||
243 | /// <param name="s">string to be examined</param> | ||
244 | /// <returns>true if slash is present</returns> | ||
245 | private static bool isSlashed(string s) | ||
246 | { | ||
247 | return s.Substring(s.Length - 1, 1) == "/"; | ||
248 | } | ||
249 | |||
250 | /// <summary> | ||
251 | /// Build a Uri based on the initial Url, path elements and parameters | ||
252 | /// </summary> | ||
253 | /// <returns>fully constructed Uri</returns> | ||
254 | private Uri buildUri() | ||
255 | { | ||
256 | StringBuilder sb = new StringBuilder(); | ||
257 | sb.Append(_url); | ||
258 | |||
259 | foreach (string e in _pathElements) | ||
260 | { | ||
261 | sb.Append("/"); | ||
262 | sb.Append(e); | ||
263 | } | ||
264 | |||
265 | bool firstElement = true; | ||
266 | foreach (KeyValuePair<string, string> kv in _parameterElements) | ||
267 | { | ||
268 | if (firstElement) | ||
269 | { | ||
270 | sb.Append("?"); | ||
271 | firstElement = false; | ||
272 | } | ||
273 | else | ||
274 | sb.Append("&"); | ||
275 | |||
276 | sb.Append(kv.Key); | ||
277 | if (!string.IsNullOrEmpty(kv.Value)) | ||
278 | { | ||
279 | sb.Append("="); | ||
280 | sb.Append(kv.Value); | ||
281 | } | ||
282 | } | ||
283 | // realuri = sb.ToString(); | ||
284 | //m_log.InfoFormat("[REST CLIENT]: RestURL: {0}", realuri); | ||
285 | return new Uri(sb.ToString()); | ||
286 | } | ||
287 | |||
288 | #region Async communications with server | ||
289 | |||
290 | /// <summary> | ||
291 | /// Async method, invoked when a block of data has been received from the service | ||
292 | /// </summary> | ||
293 | /// <param name="ar"></param> | ||
294 | private void StreamIsReadyDelegate(IAsyncResult ar) | ||
295 | { | ||
296 | try | ||
297 | { | ||
298 | Stream s = (Stream) ar.AsyncState; | ||
299 | int read = s.EndRead(ar); | ||
300 | |||
301 | if (read > 0) | ||
302 | { | ||
303 | _resource.Write(_readbuf, 0, read); | ||
304 | // IAsyncResult asynchronousResult = | ||
305 | // s.BeginRead(_readbuf, 0, BufferSize, new AsyncCallback(StreamIsReadyDelegate), s); | ||
306 | s.BeginRead(_readbuf, 0, BufferSize, new AsyncCallback(StreamIsReadyDelegate), s); | ||
307 | |||
308 | // TODO! Implement timeout, without killing the server | ||
309 | //ThreadPool.RegisterWaitForSingleObject(asynchronousResult.AsyncWaitHandle, new WaitOrTimerCallback(TimeoutCallback), _request, DefaultTimeout, true); | ||
310 | } | ||
311 | else | ||
312 | { | ||
313 | s.Close(); | ||
314 | //_allDone.Set(); | ||
315 | } | ||
316 | } | ||
317 | catch (Exception e) | ||
318 | { | ||
319 | //_allDone.Set(); | ||
320 | _asyncException = e; | ||
321 | } | ||
322 | } | ||
323 | |||
324 | #endregion Async communications with server | ||
325 | |||
326 | /// <summary> | ||
327 | /// Perform a synchronous request | ||
328 | /// </summary> | ||
329 | public Stream Request() | ||
330 | { | ||
331 | return Request(null); | ||
332 | } | ||
333 | |||
334 | /// <summary> | ||
335 | /// Perform a synchronous request | ||
336 | /// </summary> | ||
337 | public Stream Request(IServiceAuth auth) | ||
338 | { | ||
339 | lock (_lock) | ||
340 | { | ||
341 | _request = (HttpWebRequest) WebRequest.Create(buildUri()); | ||
342 | _request.KeepAlive = false; | ||
343 | _request.ContentType = "application/xml"; | ||
344 | _request.Timeout = 200000; | ||
345 | _request.Method = RequestMethod; | ||
346 | _asyncException = null; | ||
347 | if (auth != null) | ||
348 | auth.AddAuthorization(_request.Headers); | ||
349 | |||
350 | int reqnum = WebUtil.RequestNumber++; | ||
351 | if (WebUtil.DebugLevel >= 3) | ||
352 | m_log.DebugFormat("[LOGHTTP]: HTTP OUT {0} REST {1} to {2}", reqnum, _request.Method, _request.RequestUri); | ||
353 | |||
354 | // IAsyncResult responseAsyncResult = _request.BeginGetResponse(new AsyncCallback(ResponseIsReadyDelegate), _request); | ||
355 | |||
356 | try | ||
357 | { | ||
358 | using (_response = (HttpWebResponse) _request.GetResponse()) | ||
359 | { | ||
360 | using (Stream src = _response.GetResponseStream()) | ||
361 | { | ||
362 | int length = src.Read(_readbuf, 0, BufferSize); | ||
363 | while (length > 0) | ||
364 | { | ||
365 | _resource.Write(_readbuf, 0, length); | ||
366 | length = src.Read(_readbuf, 0, BufferSize); | ||
367 | } | ||
368 | |||
369 | // TODO! Implement timeout, without killing the server | ||
370 | // this line implements the timeout, if there is a timeout, the callback fires and the request becomes aborted | ||
371 | //ThreadPool.RegisterWaitForSingleObject(responseAsyncResult.AsyncWaitHandle, new WaitOrTimerCallback(TimeoutCallback), _request, DefaultTimeout, true); | ||
372 | |||
373 | // _allDone.WaitOne(); | ||
374 | } | ||
375 | } | ||
376 | } | ||
377 | catch (WebException e) | ||
378 | { | ||
379 | using (HttpWebResponse errorResponse = e.Response as HttpWebResponse) | ||
380 | { | ||
381 | if (null != errorResponse && HttpStatusCode.NotFound == errorResponse.StatusCode) | ||
382 | { | ||
383 | // This is often benign. E.g., requesting a missing asset will return 404. | ||
384 | m_log.DebugFormat("[REST CLIENT] Resource not found (404): {0}", _request.Address.ToString()); | ||
385 | } | ||
386 | else | ||
387 | { | ||
388 | m_log.Error(string.Format("[REST CLIENT] Error fetching resource from server: {0} ", _request.Address.ToString()), e); | ||
389 | } | ||
390 | } | ||
391 | |||
392 | return null; | ||
393 | } | ||
394 | |||
395 | if (_asyncException != null) | ||
396 | throw _asyncException; | ||
397 | |||
398 | if (_resource != null) | ||
399 | { | ||
400 | _resource.Flush(); | ||
401 | _resource.Seek(0, SeekOrigin.Begin); | ||
402 | } | ||
403 | |||
404 | if (WebUtil.DebugLevel >= 5) | ||
405 | WebUtil.LogResponseDetail(reqnum, _resource); | ||
406 | |||
407 | return _resource; | ||
408 | } | ||
409 | } | ||
410 | |||
411 | public Stream Request(Stream src, IServiceAuth auth) | ||
412 | { | ||
413 | _request = (HttpWebRequest) WebRequest.Create(buildUri()); | ||
414 | _request.KeepAlive = false; | ||
415 | _request.ContentType = "application/xml"; | ||
416 | _request.Timeout = 900000; | ||
417 | _request.Method = RequestMethod; | ||
418 | _asyncException = null; | ||
419 | _request.ContentLength = src.Length; | ||
420 | if (auth != null) | ||
421 | auth.AddAuthorization(_request.Headers); | ||
422 | |||
423 | src.Seek(0, SeekOrigin.Begin); | ||
424 | |||
425 | int reqnum = WebUtil.RequestNumber++; | ||
426 | if (WebUtil.DebugLevel >= 3) | ||
427 | m_log.DebugFormat("[LOGHTTP]: HTTP OUT {0} REST {1} to {2}", reqnum, _request.Method, _request.RequestUri); | ||
428 | if (WebUtil.DebugLevel >= 5) | ||
429 | WebUtil.LogOutgoingDetail(string.Format("SEND {0}: ", reqnum), src); | ||
430 | |||
431 | Stream dst = _request.GetRequestStream(); | ||
432 | |||
433 | byte[] buf = new byte[1024]; | ||
434 | int length = src.Read(buf, 0, 1024); | ||
435 | while (length > 0) | ||
436 | { | ||
437 | dst.Write(buf, 0, length); | ||
438 | length = src.Read(buf, 0, 1024); | ||
439 | } | ||
440 | |||
441 | try | ||
442 | { | ||
443 | _response = (HttpWebResponse)_request.GetResponse(); | ||
444 | } | ||
445 | catch (WebException e) | ||
446 | { | ||
447 | m_log.WarnFormat("[REST]: Request {0} {1} failed with status {2} and message {3}", | ||
448 | RequestMethod, _request.RequestUri, e.Status, e.Message); | ||
449 | return null; | ||
450 | } | ||
451 | catch (Exception e) | ||
452 | { | ||
453 | m_log.WarnFormat( | ||
454 | "[REST]: Request {0} {1} failed with exception {2} {3}", | ||
455 | RequestMethod, _request.RequestUri, e.Message, e.StackTrace); | ||
456 | return null; | ||
457 | } | ||
458 | |||
459 | if (WebUtil.DebugLevel >= 5) | ||
460 | { | ||
461 | using (Stream responseStream = _response.GetResponseStream()) | ||
462 | { | ||
463 | using (StreamReader reader = new StreamReader(responseStream)) | ||
464 | { | ||
465 | string responseStr = reader.ReadToEnd(); | ||
466 | WebUtil.LogResponseDetail(reqnum, responseStr); | ||
467 | } | ||
468 | } | ||
469 | } | ||
470 | |||
471 | _response.Close(); | ||
472 | |||
473 | // IAsyncResult responseAsyncResult = _request.BeginGetResponse(new AsyncCallback(ResponseIsReadyDelegate), _request); | ||
474 | |||
475 | // TODO! Implement timeout, without killing the server | ||
476 | // this line implements the timeout, if there is a timeout, the callback fires and the request becomes aborted | ||
477 | //ThreadPool.RegisterWaitForSingleObject(responseAsyncResult.AsyncWaitHandle, new WaitOrTimerCallback(TimeoutCallback), _request, DefaultTimeout, true); | ||
478 | |||
479 | return null; | ||
480 | } | ||
481 | |||
482 | #region Async Invocation | ||
483 | |||
484 | public IAsyncResult BeginRequest(AsyncCallback callback, object state) | ||
485 | { | ||
486 | /// <summary> | ||
487 | /// In case, we are invoked asynchroneously this object will keep track of the state | ||
488 | /// </summary> | ||
489 | AsyncResult<Stream> ar = new AsyncResult<Stream>(callback, state); | ||
490 | Util.FireAndForget(RequestHelper, ar, "RestClient.BeginRequest"); | ||
491 | return ar; | ||
492 | } | ||
493 | |||
494 | public Stream EndRequest(IAsyncResult asyncResult) | ||
495 | { | ||
496 | AsyncResult<Stream> ar = (AsyncResult<Stream>) asyncResult; | ||
497 | |||
498 | // Wait for operation to complete, then return result or | ||
499 | // throw exception | ||
500 | return ar.EndInvoke(); | ||
501 | } | ||
502 | |||
503 | private void RequestHelper(Object asyncResult) | ||
504 | { | ||
505 | // We know that it's really an AsyncResult<DateTime> object | ||
506 | AsyncResult<Stream> ar = (AsyncResult<Stream>) asyncResult; | ||
507 | try | ||
508 | { | ||
509 | // Perform the operation; if sucessful set the result | ||
510 | Stream s = Request(null); | ||
511 | ar.SetAsCompleted(s, false); | ||
512 | } | ||
513 | catch (Exception e) | ||
514 | { | ||
515 | // If operation fails, set the exception | ||
516 | ar.HandleException(e, false); | ||
517 | } | ||
518 | } | ||
519 | |||
520 | #endregion Async Invocation | ||
521 | } | ||
522 | |||
523 | internal class SimpleAsyncResult : IAsyncResult | ||
524 | { | ||
525 | private readonly AsyncCallback m_callback; | ||
526 | |||
527 | /// <summary> | ||
528 | /// Is process completed? | ||
529 | /// </summary> | ||
530 | /// <remarks>Should really be boolean, but VolatileRead has no boolean method</remarks> | ||
531 | private byte m_completed; | ||
532 | |||
533 | /// <summary> | ||
534 | /// Did process complete synchronously? | ||
535 | /// </summary> | ||
536 | /// <remarks>I have a hard time imagining a scenario where this is the case, again, same issue about | ||
537 | /// booleans and VolatileRead as m_completed | ||
538 | /// </remarks> | ||
539 | private byte m_completedSynchronously; | ||
540 | |||
541 | private readonly object m_asyncState; | ||
542 | private ManualResetEvent m_waitHandle; | ||
543 | private Exception m_exception; | ||
544 | |||
545 | internal SimpleAsyncResult(AsyncCallback cb, object state) | ||
546 | { | ||
547 | m_callback = cb; | ||
548 | m_asyncState = state; | ||
549 | m_completed = 0; | ||
550 | m_completedSynchronously = 1; | ||
551 | } | ||
552 | |||
553 | #region IAsyncResult Members | ||
554 | |||
555 | public object AsyncState | ||
556 | { | ||
557 | get { return m_asyncState; } | ||
558 | } | ||
559 | |||
560 | public WaitHandle AsyncWaitHandle | ||
561 | { | ||
562 | get | ||
563 | { | ||
564 | if (m_waitHandle == null) | ||
565 | { | ||
566 | bool done = IsCompleted; | ||
567 | ManualResetEvent mre = new ManualResetEvent(done); | ||
568 | if (Interlocked.CompareExchange(ref m_waitHandle, mre, null) != null) | ||
569 | { | ||
570 | mre.Close(); | ||
571 | } | ||
572 | else | ||
573 | { | ||
574 | if (!done && IsCompleted) | ||
575 | { | ||
576 | m_waitHandle.Set(); | ||
577 | } | ||
578 | } | ||
579 | } | ||
580 | |||
581 | return m_waitHandle; | ||
582 | } | ||
583 | } | ||
584 | |||
585 | |||
586 | public bool CompletedSynchronously | ||
587 | { | ||
588 | get { return Thread.VolatileRead(ref m_completedSynchronously) == 1; } | ||
589 | } | ||
590 | |||
591 | |||
592 | public bool IsCompleted | ||
593 | { | ||
594 | get { return Thread.VolatileRead(ref m_completed) == 1; } | ||
595 | } | ||
596 | |||
597 | #endregion | ||
598 | |||
599 | #region class Methods | ||
600 | |||
601 | internal void SetAsCompleted(bool completedSynchronously) | ||
602 | { | ||
603 | m_completed = 1; | ||
604 | if (completedSynchronously) | ||
605 | m_completedSynchronously = 1; | ||
606 | else | ||
607 | m_completedSynchronously = 0; | ||
608 | |||
609 | SignalCompletion(); | ||
610 | } | ||
611 | |||
612 | internal void HandleException(Exception e, bool completedSynchronously) | ||
613 | { | ||
614 | m_completed = 1; | ||
615 | if (completedSynchronously) | ||
616 | m_completedSynchronously = 1; | ||
617 | else | ||
618 | m_completedSynchronously = 0; | ||
619 | m_exception = e; | ||
620 | |||
621 | SignalCompletion(); | ||
622 | } | ||
623 | |||
624 | private void SignalCompletion() | ||
625 | { | ||
626 | if (m_waitHandle != null) m_waitHandle.Set(); | ||
627 | |||
628 | if (m_callback != null) m_callback(this); | ||
629 | } | ||
630 | |||
631 | public void EndInvoke() | ||
632 | { | ||
633 | // This method assumes that only 1 thread calls EndInvoke | ||
634 | if (!IsCompleted) | ||
635 | { | ||
636 | // If the operation isn't done, wait for it | ||
637 | AsyncWaitHandle.WaitOne(); | ||
638 | AsyncWaitHandle.Close(); | ||
639 | m_waitHandle.Close(); | ||
640 | m_waitHandle = null; // Allow early GC | ||
641 | } | ||
642 | |||
643 | // Operation is done: if an exception occured, throw it | ||
644 | if (m_exception != null) throw m_exception; | ||
645 | } | ||
646 | |||
647 | #endregion | ||
648 | } | ||
649 | |||
650 | internal class AsyncResult<T> : SimpleAsyncResult | ||
651 | { | ||
652 | private T m_result = default(T); | ||
653 | |||
654 | public AsyncResult(AsyncCallback asyncCallback, Object state) : | ||
655 | base(asyncCallback, state) | ||
656 | { | ||
657 | } | ||
658 | |||
659 | public void SetAsCompleted(T result, bool completedSynchronously) | ||
660 | { | ||
661 | // Save the asynchronous operation's result | ||
662 | m_result = result; | ||
663 | |||
664 | // Tell the base class that the operation completed | ||
665 | // sucessfully (no exception) | ||
666 | base.SetAsCompleted(completedSynchronously); | ||
667 | } | ||
668 | |||
669 | public new T EndInvoke() | ||
670 | { | ||
671 | base.EndInvoke(); | ||
672 | return m_result; | ||
673 | } | ||
674 | } | ||
675 | |||
676 | } \ No newline at end of file | ||