summaryrefslogtreecommitdiff
path: root/ace/Reactor_Impl.h
blob: e5ed3b2f18f953c9b88c54fc2ac820cd38847b26 (plain)
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
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
/* -*- C++ -*- */
// $Id$

// ============================================================================
//
// = LIBRARY
//    ace
//
// = FILENAME
//    Reactor_Impl.h
//
// = AUTHOR
//    Irfan Pyarali
//
// ============================================================================

#ifndef ACE_REACTOR_IMPL_H
#define ACE_REACTOR_IMPL_H

// Timer Queue is a complicated template class. A simple forward
// declaration will not work
#include "ace/Timer_Queue.h"

#if !defined (ACE_LACKS_PRAGMA_ONCE)
# pragma once
#endif /* ACE_LACKS_PRAGMA_ONCE */

// Event_Handler.h contains the definition of ACE_Reactor_Mask
#include "ace/Event_Handler.h"

// We are using 4 or 5 signal classes, we could forward declare
// them.... But Timer_Queue_T.h includes Signal.h, so I don't think
// forward declaration will be useful here
#include "ace/Signal.h"

// Forward decls
class ACE_Handle_Set;
class ACE_Reactor_Impl;

class ACE_Export ACE_Reactor_Notify : public ACE_Event_Handler
{
  // = TITLE
  //     Abstract class for unblocking an <ACE_Reactor_Impl> from its
  //     event loop.
public:
  // = Initialization and termination methods.
  virtual int open (ACE_Reactor_Impl *,
                    ACE_Timer_Queue *timer_queue = 0,
                    int disable_notify = 0) = 0;
  virtual int close (void) = 0;

  virtual ssize_t notify (ACE_Event_Handler * = 0,
                          ACE_Reactor_Mask = ACE_Event_Handler::EXCEPT_MASK,
                          ACE_Time_Value * = 0) = 0;
  // Called by a thread when it wants to unblock the <Reactor_Impl>.
  // This wakeups the <Reactor_Impl> if currently blocked.  Pass over
  // both the <Event_Handler> *and* the <mask> to allow the caller to
  // dictate which <Event_Handler> method the <Reactor_Impl> will
  // invoke.  The <ACE_Time_Value> indicates how long to blocking
  // trying to notify the <Reactor_Impl>.  If <timeout> == 0, the
  // caller will block until action is possible, else will wait until
  // the relative time specified in *<timeout> elapses).

  virtual int dispatch_notifications (int &number_of_active_handles,
                                      const ACE_Handle_Set &rd_mask) = 0;
  // Handles pending threads (if any) that are waiting to unblock the
  // <Reactor_Impl>.

  virtual void max_notify_iterations (int) = 0;
  // Set the maximum number of times that the <handle_input> method
  // will iterate and dispatch the <ACE_Event_Handlers> that are
  // passed in via the notify queue before breaking out of the event
  // loop.  By default, this is set to -1, which means "iterate until
  // the queue is empty."  Setting this to a value like "1 or 2" will
  // increase "fairness" (and thus prevent starvation) at the expense
  // of slightly higher dispatching overhead.

  virtual int max_notify_iterations (void) = 0;
  // Get the maximum number of times that the <handle_input> method
  // will iterate and dispatch the <ACE_Event_Handlers> that are
  // passed in via the notify queue before breaking out of its event
  // loop.

  virtual void dump (void) const = 0;
  // Dump the state of an object.
};

class ACE_Export ACE_Reactor_Impl
{
  // = TITLE
  //     An abstract class for implementing the Reactor Pattern.
public:
  virtual ~ACE_Reactor_Impl (void) {}
  // Close down and release all resources.

  virtual int open (size_t size,
                    int restart = 0,
                    ACE_Sig_Handler * = 0,
                    ACE_Timer_Queue * = 0,
                    int disable_notify_pipe = 0,
                    ACE_Reactor_Notify * = 0) = 0;
  // Initialization.

  virtual int current_info (ACE_HANDLE, size_t & /* size */) = 0;
  // Returns 0, if the size of the current message has been put in
  // <size> Returns -1, if not.  ACE_HANDLE allows the reactor to
  // check if the caller is valid.

  virtual int set_sig_handler (ACE_Sig_Handler *signal_handler) = 0;
  // Use a user specified signal handler instead.

  virtual int set_timer_queue (ACE_Timer_Queue *timer_queue) = 0;
  // Use a user specified timer queue instead.

  virtual int close (void) = 0;
  // Close down and release all resources.

  // = Event loop drivers.

  virtual int handle_events (ACE_Time_Value *max_wait_time = 0) = 0;
  virtual int alertable_handle_events (ACE_Time_Value *max_wait_time = 0) = 0;
  // This event loop driver blocks for up to <max_wait_time> before
  // returning.  It will return earlier if events occur.  Note that
  // <max_wait_time> can be 0, in which case this method blocks
  // indefinitely until events occur.
  //
  // <max_wait_time> is decremented to reflect how much time this call
  // took.  For instance, if a time value of 3 seconds is passed to
  // handle_events and an event occurs after 2 seconds,
  // <max_wait_time> will equal 1 second.  This can be used if an
  // application wishes to handle events for some fixed amount of
  // time.
  //
  // Returns the total number of <ACE_Event_Handler>s that were
  // dispatched, 0 if the <max_wait_time> elapsed without dispatching
  // any handlers, or -1 if an error occurs.
  //
  // The only difference between <alertable_handle_events> and
  // <handle_events> is that in the alertable case, the eventloop will
  // return when the system queues an I/O completion routine or an
  // Asynchronous Procedure Call.

  virtual int handle_events (ACE_Time_Value &max_wait_time) = 0;
  virtual int alertable_handle_events (ACE_Time_Value &max_wait_time) = 0;
  // This method is just like the one above, except the
  // <max_wait_time> value is a reference and can therefore never be
  // NULL.
  //
  // The only difference between <alertable_handle_events> and
  // <handle_events> is that in the alertable case, the eventloop will
  // return when the system queues an I/O completion routine or an
  // Asynchronous Procedure Call.

  // = Register and remove Handlers.

  virtual int register_handler (ACE_Event_Handler *event_handler,
                                ACE_Reactor_Mask mask) = 0;
  // Register <event_handler> with <mask>.  The I/O handle will always
  // come from <get_handle> on the <event_handler>.

  virtual int register_handler (ACE_HANDLE io_handle,
                                ACE_Event_Handler *event_handler,
                                ACE_Reactor_Mask mask) = 0;
  // Register <event_handler> with <mask>.  The I/O handle is provided
  // through the <io_handle> parameter.

#if defined (ACE_WIN32)

  // Originally this interface was available for all platforms, but
  // because ACE_HANDLE is an int on non-Win32 platforms, compilers
  // are not able to tell the difference between
  // register_handler(ACE_Event_Handler*,ACE_Reactor_Mask) and
  // register_handler(ACE_Event_Handler*,ACE_HANDLE). Therefore, we
  // have restricted this method to Win32 only.

  virtual int register_handler (ACE_Event_Handler *event_handler,
                                ACE_HANDLE event_handle = ACE_INVALID_HANDLE) = 0;
  // Register an <event_handler> that will be notified when
  // <event_handle> is signaled.  Since no event mask is passed
  // through this interface, it is assumed that the <event_handle>
  // being passed in is an event handle and not an I/O handle.

#endif /* ACE_WIN32 */

  virtual int register_handler (ACE_HANDLE event_handle,
                                ACE_HANDLE io_handle,
                                ACE_Event_Handler *event_handler,
                                ACE_Reactor_Mask mask) = 0;
  // Register an <event_handler> that will be notified when
  // <event_handle> is signaled.  <mask> specifies the network events
  // that the <event_handler> is interested in.

  virtual int register_handler (const ACE_Handle_Set &handles,
                                ACE_Event_Handler *event_handler,
                                ACE_Reactor_Mask mask) = 0;
  // Register <event_handler> with all the <handles> in the <Handle_Set>.

  virtual int register_handler (int signum,
                                ACE_Event_Handler *new_sh,
                                ACE_Sig_Action *new_disp = 0,
                                ACE_Event_Handler **old_sh = 0,
                                ACE_Sig_Action *old_disp = 0) = 0;
  // Register <new_sh> to handle the signal <signum> using the
  // <new_disp>.  Returns the <old_sh> that was previously registered
  // (if any), along with the <old_disp> of the signal handler.

  virtual int register_handler (const ACE_Sig_Set &sigset,
                                ACE_Event_Handler *new_sh,
                                ACE_Sig_Action *new_disp = 0) = 0;
  // Registers <new_sh> to handle a set of signals <sigset> using the
  // <new_disp>.

  virtual int remove_handler (ACE_Event_Handler *event_handler,
                              ACE_Reactor_Mask mask) = 0;
  // Removes <event_handler>.  Note that the I/O handle will be
  // obtained using <get_handle> method of <event_handler> .  If
  // <mask> == <ACE_Event_Handler::DONT_CALL> then the <handle_close>
  // method of the <event_handler> is not invoked.

  virtual int remove_handler (ACE_HANDLE handle,
                              ACE_Reactor_Mask mask) = 0;
  // Removes <handle>.  If <mask> == <ACE_Event_Handler::DONT_CALL>
  // then the <handle_close> method of the associated <event_handler>
  // is not invoked.

  virtual int remove_handler (const ACE_Handle_Set &handle_set,
                              ACE_Reactor_Mask mask) = 0;
  // Removes all handles in <handle_set>.  If <mask> ==
  // <ACE_Event_Handler::DONT_CALL> then the <handle_close> method of
  // the associated <event_handler>s is not invoked.

  virtual int remove_handler (int signum,
                              ACE_Sig_Action *new_disp,
                              ACE_Sig_Action *old_disp = 0,
                              int sigkey = -1) = 0;
  // Remove the ACE_Event_Handler currently associated with <signum>.
  // Install the new disposition (if given) and return the previous
  // disposition (if desired by the caller).  Returns 0 on success and
  // -1 if <signum> is invalid.

  virtual int remove_handler (const ACE_Sig_Set &sigset) = 0;
  // Calls <remove_handler> for every signal in <sigset>.

  // = Suspend and resume Handlers.

  virtual int suspend_handler (ACE_Event_Handler *event_handler) = 0;
  // Suspend <event_handler> temporarily.  Use
  // <event_handler->get_handle()> to get the handle.

  virtual int suspend_handler (ACE_HANDLE handle) = 0;
  // Suspend <handle> temporarily.

  virtual int suspend_handler (const ACE_Handle_Set &handles) = 0;
  // Suspend all <handles> in handle set temporarily.

  virtual int suspend_handlers (void) = 0;
  // Suspend all <handles> temporarily.

  virtual int resume_handler (ACE_Event_Handler *event_handler) = 0;
  // Resume <event_handler>. Use <event_handler->get_handle()> to get
  // the handle.

  virtual int resume_handler (ACE_HANDLE handle) = 0;
  // Resume <handle>.

  virtual int resume_handler (const ACE_Handle_Set &handles) = 0;
  // Resume all <handles> in handle set.

  virtual int resume_handlers (void) = 0;
  // Resume all <handles>.

  virtual int uses_event_associations (void) = 0;
  // Return 1 if we any event associations were made by the reactor
  // for the handles that it waits on, 0 otherwise.

  // If we need to reset handles returned from accept/connect.

  // Timer management.

  virtual long schedule_timer (ACE_Event_Handler *event_handler,
                               const void *arg,
                               const ACE_Time_Value &delta,
                               const ACE_Time_Value &interval = ACE_Time_Value::zero) = 0;
  // Schedule an <event_handler> that will expire after <delay> amount
  // of time.  If it expires then <arg> is passed in as the value to
  // the <event_handler>'s <handle_timeout> callback method.  If
  // <interval> is != to <ACE_Time_Value::zero> then it is used to
  // reschedule the <event_handler> automatically.  This method
  // returns a <timer_id> that uniquely identifies the <event_handler>
  // in an internal list.  This <timer_id> can be used to cancel an
  // <event_handler> before it expires.  The cancellation ensures that
  // <timer_ids> are unique up to values of greater than 2 billion
  // timers.  As long as timers don't stay around longer than this
  // there should be no problems with accidentally deleting the wrong
  // timer.  Returns -1 on failure (which is guaranteed never to be a
  // valid <timer_id>.

  virtual int cancel_timer (ACE_Event_Handler *event_handler,
                            int dont_call_handle_close = 1) = 0;
  // Cancel all Event_Handlers that match the address of
  // <event_handler>.  Returns number of handlers cancelled.

  virtual int cancel_timer (long timer_id,
                            const void **arg = 0,
                            int dont_call_handle_close = 1) = 0;
  // Cancel the single Event_Handler that matches the <timer_id> value
  // (which was returned from the schedule method).  If arg is
  // non-NULL then it will be set to point to the ``magic cookie''
  // argument passed in when the Event_Handler was registered.  This
  // makes it possible to free up the memory and avoid memory leaks.
  // Returns 1 if cancellation succeeded and 0 if the <timer_id>
  // wasn't found.

  // = High-level Event_Handler scheduling operations

  virtual int schedule_wakeup (ACE_Event_Handler *event_handler,
                               ACE_Reactor_Mask masks_to_be_added) = 0;
  // Add <masks_to_be_added> to the <event_handler>'s entry.
  // <event_handler> must already have been registered.

  virtual int schedule_wakeup (ACE_HANDLE handle,
                               ACE_Reactor_Mask masks_to_be_added) = 0;
  // Add <masks_to_be_added> to the <handle>'s entry.  <event_handler>
  // associated with <handle> must already have been registered.

  virtual int cancel_wakeup (ACE_Event_Handler *event_handler,
                             ACE_Reactor_Mask masks_to_be_cleared) = 0;
  // Clear <masks_to_be_cleared> from the <event_handler>'s entry.

  virtual int cancel_wakeup (ACE_HANDLE handle,
                             ACE_Reactor_Mask masks_to_be_cleared) = 0;
  // Clear <masks_to_be_cleared> from the <handle>'s entry.

  // = Notification methods.

  virtual int notify (ACE_Event_Handler *event_handler = 0,
                      ACE_Reactor_Mask mask = ACE_Event_Handler::EXCEPT_MASK,
                      ACE_Time_Value * = 0) = 0;
  // Notify <event_handler> of <mask> event.  The <ACE_Time_Value>
  // indicates how long to blocking trying to notify.  If <timeout> ==
  // 0, the caller will block until action is possible, else will wait
  // until the relative time specified in <timeout> elapses).

  virtual void max_notify_iterations (int) = 0;
  // Set the maximum number of times that ACE_Reactor_Impl will
  // iterate and dispatch the <ACE_Event_Handlers> that are passed in
  // via the notify queue before breaking out of its
  // <ACE_Message_Queue::dequeue> loop.  By default, this is set to
  // -1, which means "iterate until the queue is empty."  Setting this
  // to a value like "1 or 2" will increase "fairness" (and thus
  // prevent starvation) at the expense of slightly higher dispatching
  // overhead.

  virtual int max_notify_iterations (void) = 0;
  // Get the maximum number of times that the ACE_Reactor_Impl will
  // iterate and dispatch the <ACE_Event_Handlers> that are passed in
  // via the notify queue before breaking out of its
  // <ACE_Message_Queue::dequeue> loop.

  virtual int handler (ACE_HANDLE handle,
                       ACE_Reactor_Mask mask,
                       ACE_Event_Handler **event_handler = 0) = 0;
  // Check to see if <handle> is associated with a valid Event_Handler
  // bound to <mask>.  Return the <event_handler> associated with this
  // <handler> if <event_handler> != 0.

  virtual int handler (int signum,
                       ACE_Event_Handler ** = 0) = 0;
  // Check to see if <signum> is associated with a valid Event_Handler
  // bound to a signal.  Return the <event_handler> associated with
  // this <handler> if <event_handler> != 0.

  virtual int initialized (void) = 0;
  // Returns true if Reactor has been successfully initialized, else
  // false.

  virtual size_t size (void) = 0;
  // Returns the current size of the Reactor's internal descriptor
  // table.

  virtual ACE_Lock &lock (void) = 0;
  // Returns a reference to the Reactor's internal lock.

  virtual void wakeup_all_threads (void) = 0;
  // Wake up all threads in waiting in the event loop

  virtual int owner (ACE_thread_t new_owner, ACE_thread_t *old_owner = 0) = 0;
  // Transfers ownership of Reactor_Impl to the <new_owner>.

  virtual int owner (ACE_thread_t *owner) = 0;
  // Return the ID of the "owner" thread.

  virtual void requeue_position (int) = 0;
  // Set position of the owner thread.

  virtual int requeue_position (void) = 0;
  // Get position of the owner thread.

  // = Low-level wait_set mask manipulation methods.

  virtual int mask_ops (ACE_Event_Handler *event_handler,
                        ACE_Reactor_Mask mask,
                        int ops) = 0;
  // GET/SET/ADD/CLR the dispatch mask "bit" bound with the
  // <event_handler> and <mask>.

  virtual int mask_ops (ACE_HANDLE handle,
                        ACE_Reactor_Mask mask,
                        int ops) = 0;
  // GET/SET/ADD/CLR the dispatch MASK "bit" bound with the <handle>
  // and <mask>.

  // = Low-level ready_set mask manipulation methods.
  virtual int ready_ops (ACE_Event_Handler *event_handler,
                         ACE_Reactor_Mask mask,
                         int ops) = 0;
  // GET/SET/ADD/CLR the ready "bit" bound with the <event_handler>
  // and <mask>.

  virtual int ready_ops (ACE_HANDLE handle,
                         ACE_Reactor_Mask,
                         int ops) = 0;
  // GET/SET/ADD/CLR the ready "bit" bound with the <handle> and <mask>.

  virtual void dump (void) const = 0;
  // Dump the state of an object.

  ACE_ALLOC_HOOK_DECLARE;
  // Declare the dynamic allocation hooks.
};

#endif /* ACE_REACTOR_IMPL_H */