1 /*
2  * This file is part of gtkD.
3  *
4  * gtkD is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU Lesser General Public License
6  * as published by the Free Software Foundation; either version 3
7  * of the License, or (at your option) any later version, with
8  * some exceptions, please read the COPYING file.
9  *
10  * gtkD is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU Lesser General Public License for more details.
14  *
15  * You should have received a copy of the GNU Lesser General Public License
16  * along with gtkD; if not, write to the Free Software
17  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110, USA
18  */
19 
20 // generated automatically - do not change
21 // find conversion definition on APILookup.txt
22 // implement new conversion functionalities on the wrap.utils pakage
23 
24 
25 module gio.Task;
26 
27 private import gio.AsyncResultIF;
28 private import gio.AsyncResultT;
29 private import gio.Cancellable;
30 private import glib.ConstructionException;
31 private import glib.ErrorG;
32 private import glib.GException;
33 private import glib.MainContext;
34 private import glib.Source;
35 private import glib.Str;
36 private import gobject.ObjectG;
37 private import gtkc.gio;
38 public  import gtkc.giotypes;
39 
40 
41 /**
42  * A #GTask represents and manages a cancellable "task".
43  * 
44  * ## Asynchronous operations
45  * 
46  * The most common usage of #GTask is as a #GAsyncResult, to
47  * manage data during an asynchronous operation. You call
48  * g_task_new() in the "start" method, followed by
49  * g_task_set_task_data() and the like if you need to keep some
50  * additional data associated with the task, and then pass the
51  * task object around through your asynchronous operation.
52  * Eventually, you will call a method such as
53  * g_task_return_pointer() or g_task_return_error(), which will
54  * save the value you give it and then invoke the task's callback
55  * function (waiting until the next iteration of the main
56  * loop first, if necessary). The caller will pass the #GTask back
57  * to the operation's finish function (as a #GAsyncResult), and
58  * you can use g_task_propagate_pointer() or the like to extract
59  * the return value.
60  * 
61  * Here is an example for using GTask as a GAsyncResult:
62  * |[<!-- language="C" -->
63  * typedef struct {
64  * CakeFrostingType frosting;
65  * char *message;
66  * } DecorationData;
67  * 
68  * static void
69  * decoration_data_free (DecorationData *decoration)
70  * {
71  * g_free (decoration->message);
72  * g_slice_free (DecorationData, decoration);
73  * }
74  * 
75  * static void
76  * baked_cb (Cake     *cake,
77  * gpointer  user_data)
78  * {
79  * GTask *task = user_data;
80  * DecorationData *decoration = g_task_get_task_data (task);
81  * GError *error = NULL;
82  * 
83  * if (cake == NULL)
84  * {
85  * g_task_return_new_error (task, BAKER_ERROR, BAKER_ERROR_NO_FLOUR,
86  * "Go to the supermarket");
87  * g_object_unref (task);
88  * return;
89  * }
90  * 
91  * if (!cake_decorate (cake, decoration->frosting, decoration->message, &error))
92  * {
93  * g_object_unref (cake);
94  * // g_task_return_error() takes ownership of error
95  * g_task_return_error (task, error);
96  * g_object_unref (task);
97  * return;
98  * }
99  * 
100  * g_task_return_pointer (task, cake, g_object_unref);
101  * g_object_unref (task);
102  * }
103  * 
104  * void
105  * baker_bake_cake_async (Baker               *self,
106  * guint                radius,
107  * CakeFlavor           flavor,
108  * CakeFrostingType     frosting,
109  * const char          *message,
110  * GCancellable        *cancellable,
111  * GAsyncReadyCallback  callback,
112  * gpointer             user_data)
113  * {
114  * GTask *task;
115  * DecorationData *decoration;
116  * Cake  *cake;
117  * 
118  * task = g_task_new (self, cancellable, callback, user_data);
119  * if (radius < 3)
120  * {
121  * g_task_return_new_error (task, BAKER_ERROR, BAKER_ERROR_TOO_SMALL,
122  * "%ucm radius cakes are silly",
123  * radius);
124  * g_object_unref (task);
125  * return;
126  * }
127  * 
128  * cake = _baker_get_cached_cake (self, radius, flavor, frosting, message);
129  * if (cake != NULL)
130  * {
131  * // _baker_get_cached_cake() returns a reffed cake
132  * g_task_return_pointer (task, cake, g_object_unref);
133  * g_object_unref (task);
134  * return;
135  * }
136  * 
137  * decoration = g_slice_new (DecorationData);
138  * decoration->frosting = frosting;
139  * decoration->message = g_strdup (message);
140  * g_task_set_task_data (task, decoration, (GDestroyNotify) decoration_data_free);
141  * 
142  * _baker_begin_cake (self, radius, flavor, cancellable, baked_cb, task);
143  * }
144  * 
145  * Cake *
146  * baker_bake_cake_finish (Baker         *self,
147  * GAsyncResult  *result,
148  * GError       **error)
149  * {
150  * g_return_val_if_fail (g_task_is_valid (result, self), NULL);
151  * 
152  * return g_task_propagate_pointer (G_TASK (result), error);
153  * }
154  * ]|
155  * 
156  * ## Chained asynchronous operations
157  * 
158  * #GTask also tries to simplify asynchronous operations that
159  * internally chain together several smaller asynchronous
160  * operations. g_task_get_cancellable(), g_task_get_context(),
161  * and g_task_get_priority() allow you to get back the task's
162  * #GCancellable, #GMainContext, and [I/O priority][io-priority]
163  * when starting a new subtask, so you don't have to keep track
164  * of them yourself. g_task_attach_source() simplifies the case
165  * of waiting for a source to fire (automatically using the correct
166  * #GMainContext and priority).
167  * 
168  * Here is an example for chained asynchronous operations:
169  * |[<!-- language="C" -->
170  * typedef struct {
171  * Cake *cake;
172  * CakeFrostingType frosting;
173  * char *message;
174  * } BakingData;
175  * 
176  * static void
177  * decoration_data_free (BakingData *bd)
178  * {
179  * if (bd->cake)
180  * g_object_unref (bd->cake);
181  * g_free (bd->message);
182  * g_slice_free (BakingData, bd);
183  * }
184  * 
185  * static void
186  * decorated_cb (Cake         *cake,
187  * GAsyncResult *result,
188  * gpointer      user_data)
189  * {
190  * GTask *task = user_data;
191  * GError *error = NULL;
192  * 
193  * if (!cake_decorate_finish (cake, result, &error))
194  * {
195  * g_object_unref (cake);
196  * g_task_return_error (task, error);
197  * g_object_unref (task);
198  * return;
199  * }
200  * 
201  * // baking_data_free() will drop its ref on the cake, so we have to
202  * // take another here to give to the caller.
203  * g_task_return_pointer (result, g_object_ref (cake), g_object_unref);
204  * g_object_unref (task);
205  * }
206  * 
207  * static void
208  * decorator_ready (gpointer user_data)
209  * {
210  * GTask *task = user_data;
211  * BakingData *bd = g_task_get_task_data (task);
212  * 
213  * cake_decorate_async (bd->cake, bd->frosting, bd->message,
214  * g_task_get_cancellable (task),
215  * decorated_cb, task);
216  * }
217  * 
218  * static void
219  * baked_cb (Cake     *cake,
220  * gpointer  user_data)
221  * {
222  * GTask *task = user_data;
223  * BakingData *bd = g_task_get_task_data (task);
224  * GError *error = NULL;
225  * 
226  * if (cake == NULL)
227  * {
228  * g_task_return_new_error (task, BAKER_ERROR, BAKER_ERROR_NO_FLOUR,
229  * "Go to the supermarket");
230  * g_object_unref (task);
231  * return;
232  * }
233  * 
234  * bd->cake = cake;
235  * 
236  * // Bail out now if the user has already cancelled
237  * if (g_task_return_error_if_cancelled (task))
238  * {
239  * g_object_unref (task);
240  * return;
241  * }
242  * 
243  * if (cake_decorator_available (cake))
244  * decorator_ready (task);
245  * else
246  * {
247  * GSource *source;
248  * 
249  * source = cake_decorator_wait_source_new (cake);
250  * // Attach @source to @task's GMainContext and have it call
251  * // decorator_ready() when it is ready.
252  * g_task_attach_source (task, source,
253  * G_CALLBACK (decorator_ready));
254  * g_source_unref (source);
255  * }
256  * }
257  * 
258  * void
259  * baker_bake_cake_async (Baker               *self,
260  * guint                radius,
261  * CakeFlavor           flavor,
262  * CakeFrostingType     frosting,
263  * const char          *message,
264  * gint                 priority,
265  * GCancellable        *cancellable,
266  * GAsyncReadyCallback  callback,
267  * gpointer             user_data)
268  * {
269  * GTask *task;
270  * BakingData *bd;
271  * 
272  * task = g_task_new (self, cancellable, callback, user_data);
273  * g_task_set_priority (task, priority);
274  * 
275  * bd = g_slice_new0 (BakingData);
276  * bd->frosting = frosting;
277  * bd->message = g_strdup (message);
278  * g_task_set_task_data (task, bd, (GDestroyNotify) baking_data_free);
279  * 
280  * _baker_begin_cake (self, radius, flavor, cancellable, baked_cb, task);
281  * }
282  * 
283  * Cake *
284  * baker_bake_cake_finish (Baker         *self,
285  * GAsyncResult  *result,
286  * GError       **error)
287  * {
288  * g_return_val_if_fail (g_task_is_valid (result, self), NULL);
289  * 
290  * return g_task_propagate_pointer (G_TASK (result), error);
291  * }
292  * ]|
293  * 
294  * ## Asynchronous operations from synchronous ones
295  * 
296  * You can use g_task_run_in_thread() to turn a synchronous
297  * operation into an asynchronous one, by running it in a thread
298  * which will then dispatch the result back to the caller's
299  * #GMainContext when it completes.
300  * 
301  * Running a task in a thread:
302  * |[<!-- language="C" -->
303  * typedef struct {
304  * guint radius;
305  * CakeFlavor flavor;
306  * CakeFrostingType frosting;
307  * char *message;
308  * } CakeData;
309  * 
310  * static void
311  * cake_data_free (CakeData *cake_data)
312  * {
313  * g_free (cake_data->message);
314  * g_slice_free (CakeData, cake_data);
315  * }
316  * 
317  * static void
318  * bake_cake_thread (GTask         *task,
319  * gpointer       source_object,
320  * gpointer       task_data,
321  * GCancellable  *cancellable)
322  * {
323  * Baker *self = source_object;
324  * CakeData *cake_data = task_data;
325  * Cake *cake;
326  * GError *error = NULL;
327  * 
328  * cake = bake_cake (baker, cake_data->radius, cake_data->flavor,
329  * cake_data->frosting, cake_data->message,
330  * cancellable, &error);
331  * if (cake)
332  * g_task_return_pointer (task, cake, g_object_unref);
333  * else
334  * g_task_return_error (task, error);
335  * }
336  * 
337  * void
338  * baker_bake_cake_async (Baker               *self,
339  * guint                radius,
340  * CakeFlavor           flavor,
341  * CakeFrostingType     frosting,
342  * const char          *message,
343  * GCancellable        *cancellable,
344  * GAsyncReadyCallback  callback,
345  * gpointer             user_data)
346  * {
347  * CakeData *cake_data;
348  * GTask *task;
349  * 
350  * cake_data = g_slice_new (CakeData);
351  * cake_data->radius = radius;
352  * cake_data->flavor = flavor;
353  * cake_data->frosting = frosting;
354  * cake_data->message = g_strdup (message);
355  * task = g_task_new (self, cancellable, callback, user_data);
356  * g_task_set_task_data (task, cake_data, (GDestroyNotify) cake_data_free);
357  * g_task_run_in_thread (task, bake_cake_thread);
358  * g_object_unref (task);
359  * }
360  * 
361  * Cake *
362  * baker_bake_cake_finish (Baker         *self,
363  * GAsyncResult  *result,
364  * GError       **error)
365  * {
366  * g_return_val_if_fail (g_task_is_valid (result, self), NULL);
367  * 
368  * return g_task_propagate_pointer (G_TASK (result), error);
369  * }
370  * ]|
371  * 
372  * ## Adding cancellability to uncancellable tasks
373  * 
374  * Finally, g_task_run_in_thread() and g_task_run_in_thread_sync()
375  * can be used to turn an uncancellable operation into a
376  * cancellable one. If you call g_task_set_return_on_cancel(),
377  * passing %TRUE, then if the task's #GCancellable is cancelled,
378  * it will return control back to the caller immediately, while
379  * allowing the task thread to continue running in the background
380  * (and simply discarding its result when it finally does finish).
381  * Provided that the task thread is careful about how it uses
382  * locks and other externally-visible resources, this allows you
383  * to make "GLib-friendly" asynchronous and cancellable
384  * synchronous variants of blocking APIs.
385  * 
386  * Cancelling a task:
387  * |[<!-- language="C" -->
388  * static void
389  * bake_cake_thread (GTask         *task,
390  * gpointer       source_object,
391  * gpointer       task_data,
392  * GCancellable  *cancellable)
393  * {
394  * Baker *self = source_object;
395  * CakeData *cake_data = task_data;
396  * Cake *cake;
397  * GError *error = NULL;
398  * 
399  * cake = bake_cake (baker, cake_data->radius, cake_data->flavor,
400  * cake_data->frosting, cake_data->message,
401  * &error);
402  * if (error)
403  * {
404  * g_task_return_error (task, error);
405  * return;
406  * }
407  * 
408  * // If the task has already been cancelled, then we don't want to add
409  * // the cake to the cake cache. Likewise, we don't  want to have the
410  * // task get cancelled in the middle of updating the cache.
411  * // g_task_set_return_on_cancel() will return %TRUE here if it managed
412  * // to disable return-on-cancel, or %FALSE if the task was cancelled
413  * // before it could.
414  * if (g_task_set_return_on_cancel (task, FALSE))
415  * {
416  * // If the caller cancels at this point, their
417  * // GAsyncReadyCallback won't be invoked until we return,
418  * // so we don't have to worry that this code will run at
419  * // the same time as that code does. But if there were
420  * // other functions that might look at the cake cache,
421  * // then we'd probably need a GMutex here as well.
422  * baker_add_cake_to_cache (baker, cake);
423  * g_task_return_pointer (task, cake, g_object_unref);
424  * }
425  * }
426  * 
427  * void
428  * baker_bake_cake_async (Baker               *self,
429  * guint                radius,
430  * CakeFlavor           flavor,
431  * CakeFrostingType     frosting,
432  * const char          *message,
433  * GCancellable        *cancellable,
434  * GAsyncReadyCallback  callback,
435  * gpointer             user_data)
436  * {
437  * CakeData *cake_data;
438  * GTask *task;
439  * 
440  * cake_data = g_slice_new (CakeData);
441  * 
442  * ...
443  * 
444  * task = g_task_new (self, cancellable, callback, user_data);
445  * g_task_set_task_data (task, cake_data, (GDestroyNotify) cake_data_free);
446  * g_task_set_return_on_cancel (task, TRUE);
447  * g_task_run_in_thread (task, bake_cake_thread);
448  * }
449  * 
450  * Cake *
451  * baker_bake_cake_sync (Baker               *self,
452  * guint                radius,
453  * CakeFlavor           flavor,
454  * CakeFrostingType     frosting,
455  * const char          *message,
456  * GCancellable        *cancellable,
457  * GError             **error)
458  * {
459  * CakeData *cake_data;
460  * GTask *task;
461  * Cake *cake;
462  * 
463  * cake_data = g_slice_new (CakeData);
464  * 
465  * ...
466  * 
467  * task = g_task_new (self, cancellable, NULL, NULL);
468  * g_task_set_task_data (task, cake_data, (GDestroyNotify) cake_data_free);
469  * g_task_set_return_on_cancel (task, TRUE);
470  * g_task_run_in_thread_sync (task, bake_cake_thread);
471  * 
472  * cake = g_task_propagate_pointer (task, error);
473  * g_object_unref (task);
474  * return cake;
475  * }
476  * ]|
477  * 
478  * ## Porting from GSimpleAsyncResult
479  * 
480  * #GTask's API attempts to be simpler than #GSimpleAsyncResult's
481  * in several ways:
482  * - You can save task-specific data with g_task_set_task_data(), and
483  * retrieve it later with g_task_get_task_data(). This replaces the
484  * abuse of g_simple_async_result_set_op_res_gpointer() for the same
485  * purpose with #GSimpleAsyncResult.
486  * - In addition to the task data, #GTask also keeps track of the
487  * [priority][io-priority], #GCancellable, and
488  * #GMainContext associated with the task, so tasks that consist of
489  * a chain of simpler asynchronous operations will have easy access
490  * to those values when starting each sub-task.
491  * - g_task_return_error_if_cancelled() provides simplified
492  * handling for cancellation. In addition, cancellation
493  * overrides any other #GTask return value by default, like
494  * #GSimpleAsyncResult does when
495  * g_simple_async_result_set_check_cancellable() is called.
496  * (You can use g_task_set_check_cancellable() to turn off that
497  * behavior.) On the other hand, g_task_run_in_thread()
498  * guarantees that it will always run your
499  * `task_func`, even if the task's #GCancellable
500  * is already cancelled before the task gets a chance to run;
501  * you can start your `task_func` with a
502  * g_task_return_error_if_cancelled() check if you need the
503  * old behavior.
504  * - The "return" methods (eg, g_task_return_pointer())
505  * automatically cause the task to be "completed" as well, and
506  * there is no need to worry about the "complete" vs "complete
507  * in idle" distinction. (#GTask automatically figures out
508  * whether the task's callback can be invoked directly, or
509  * if it needs to be sent to another #GMainContext, or delayed
510  * until the next iteration of the current #GMainContext.)
511  * - The "finish" functions for #GTask-based operations are generally
512  * much simpler than #GSimpleAsyncResult ones, normally consisting
513  * of only a single call to g_task_propagate_pointer() or the like.
514  * Since g_task_propagate_pointer() "steals" the return value from
515  * the #GTask, it is not necessary to juggle pointers around to
516  * prevent it from being freed twice.
517  * - With #GSimpleAsyncResult, it was common to call
518  * g_simple_async_result_propagate_error() from the
519  * `_finish()` wrapper function, and have
520  * virtual method implementations only deal with successful
521  * returns. This behavior is deprecated, because it makes it
522  * difficult for a subclass to chain to a parent class's async
523  * methods. Instead, the wrapper function should just be a
524  * simple wrapper, and the virtual method should call an
525  * appropriate `g_task_propagate_` function.
526  * Note that wrapper methods can now use
527  * g_async_result_legacy_propagate_error() to do old-style
528  * #GSimpleAsyncResult error-returning behavior, and
529  * g_async_result_is_tagged() to check if a result is tagged as
530  * having come from the `_async()` wrapper
531  * function (for "short-circuit" results, such as when passing
532  * 0 to g_input_stream_read_async()).
533  */
534 public class Task : ObjectG, AsyncResultIF
535 {
536 	/** the main Gtk struct */
537 	protected GTask* gTask;
538 
539 	/** Get the main Gtk struct */
540 	public GTask* getTaskStruct()
541 	{
542 		return gTask;
543 	}
544 
545 	/** the main Gtk struct as a void* */
546 	protected override void* getStruct()
547 	{
548 		return cast(void*)gTask;
549 	}
550 
551 	protected override void setStruct(GObject* obj)
552 	{
553 		gTask = cast(GTask*)obj;
554 		super.setStruct(obj);
555 	}
556 
557 	/**
558 	 * Sets our main struct and passes it to the parent class.
559 	 */
560 	public this (GTask* gTask, bool ownedRef = false)
561 	{
562 		this.gTask = gTask;
563 		super(cast(GObject*)gTask, ownedRef);
564 	}
565 
566 	// add the AsyncResult capabilities
567 	mixin AsyncResultT!(GTask);
568 
569 	/**
570 	 */
571 
572 	public static GType getType()
573 	{
574 		return g_task_get_type();
575 	}
576 
577 	/**
578 	 * Creates a #GTask acting on @source_object, which will eventually be
579 	 * used to invoke @callback in the current
580 	 * [thread-default main context][g-main-context-push-thread-default].
581 	 *
582 	 * Call this in the "start" method of your asynchronous method, and
583 	 * pass the #GTask around throughout the asynchronous operation. You
584 	 * can use g_task_set_task_data() to attach task-specific data to the
585 	 * object, which you can retrieve later via g_task_get_task_data().
586 	 *
587 	 * By default, if @cancellable is cancelled, then the return value of
588 	 * the task will always be %G_IO_ERROR_CANCELLED, even if the task had
589 	 * already completed before the cancellation. This allows for
590 	 * simplified handling in cases where cancellation may imply that
591 	 * other objects that the task depends on have been destroyed. If you
592 	 * do not want this behavior, you can use
593 	 * g_task_set_check_cancellable() to change it.
594 	 *
595 	 * Params:
596 	 *     sourceObject = the #GObject that owns
597 	 *         this task, or %NULL.
598 	 *     cancellable = optional #GCancellable object, %NULL to ignore.
599 	 *     callback = a #GAsyncReadyCallback.
600 	 *     callbackData = user data passed to @callback.
601 	 *
602 	 * Return: a #GTask.
603 	 *
604 	 * Since: 2.36
605 	 *
606 	 * Throws: ConstructionException GTK+ fails to create the object.
607 	 */
608 	public this(ObjectG sourceObject, Cancellable cancellable, GAsyncReadyCallback callback, void* callbackData)
609 	{
610 		auto p = g_task_new((sourceObject is null) ? null : sourceObject.getObjectGStruct(), (cancellable is null) ? null : cancellable.getCancellableStruct(), callback, callbackData);
611 		
612 		if(p is null)
613 		{
614 			throw new ConstructionException("null returned by new");
615 		}
616 		
617 		this(cast(GTask*) p, true);
618 	}
619 
620 	/**
621 	 * Checks that @result is a #GTask, and that @source_object is its
622 	 * source object (or that @source_object is %NULL and @result has no
623 	 * source object). This can be used in g_return_if_fail() checks.
624 	 *
625 	 * Params:
626 	 *     result = A #GAsyncResult
627 	 *     sourceObject = the source object
628 	 *         expected to be associated with the task
629 	 *
630 	 * Return: %TRUE if @result and @source_object are valid, %FALSE
631 	 *     if not
632 	 *
633 	 * Since: 2.36
634 	 */
635 	public static bool isValid(AsyncResultIF result, ObjectG sourceObject)
636 	{
637 		return g_task_is_valid((result is null) ? null : result.getAsyncResultStruct(), (sourceObject is null) ? null : sourceObject.getObjectGStruct()) != 0;
638 	}
639 
640 	/**
641 	 * Creates a #GTask and then immediately calls g_task_return_error()
642 	 * on it. Use this in the wrapper function of an asynchronous method
643 	 * when you want to avoid even calling the virtual method. You can
644 	 * then use g_async_result_is_tagged() in the finish method wrapper to
645 	 * check if the result there is tagged as having been created by the
646 	 * wrapper method, and deal with it appropriately if so.
647 	 *
648 	 * See also g_task_report_new_error().
649 	 *
650 	 * Params:
651 	 *     sourceObject = the #GObject that owns
652 	 *         this task, or %NULL.
653 	 *     callback = a #GAsyncReadyCallback.
654 	 *     callbackData = user data passed to @callback.
655 	 *     sourceTag = an opaque pointer indicating the source of this task
656 	 *     error = error to report
657 	 *
658 	 * Since: 2.36
659 	 */
660 	public static void reportError(ObjectG sourceObject, GAsyncReadyCallback callback, void* callbackData, void* sourceTag, ErrorG error)
661 	{
662 		g_task_report_error((sourceObject is null) ? null : sourceObject.getObjectGStruct(), callback, callbackData, sourceTag, (error is null) ? null : error.getErrorGStruct());
663 	}
664 
665 	/**
666 	 * A utility function for dealing with async operations where you need
667 	 * to wait for a #GSource to trigger. Attaches @source to @task's
668 	 * #GMainContext with @task's [priority][io-priority], and sets @source's
669 	 * callback to @callback, with @task as the callback's `user_data`.
670 	 *
671 	 * This takes a reference on @task until @source is destroyed.
672 	 *
673 	 * Params:
674 	 *     source = the source to attach
675 	 *     callback = the callback to invoke when @source triggers
676 	 *
677 	 * Since: 2.36
678 	 */
679 	public void attachSource(Source source, GSourceFunc callback)
680 	{
681 		g_task_attach_source(gTask, (source is null) ? null : source.getSourceStruct(), callback);
682 	}
683 
684 	/**
685 	 * Gets @task's #GCancellable
686 	 *
687 	 * Return: @task's #GCancellable
688 	 *
689 	 * Since: 2.36
690 	 */
691 	public Cancellable getCancellable()
692 	{
693 		auto p = g_task_get_cancellable(gTask);
694 		
695 		if(p is null)
696 		{
697 			return null;
698 		}
699 		
700 		return ObjectG.getDObject!(Cancellable)(cast(GCancellable*) p);
701 	}
702 
703 	/**
704 	 * Gets @task's check-cancellable flag. See
705 	 * g_task_set_check_cancellable() for more details.
706 	 *
707 	 * Since: 2.36
708 	 */
709 	public bool getCheckCancellable()
710 	{
711 		return g_task_get_check_cancellable(gTask) != 0;
712 	}
713 
714 	/**
715 	 * Gets the value of #GTask:completed. This changes from %FALSE to %TRUE after
716 	 * the task’s callback is invoked, and will return %FALSE if called from inside
717 	 * the callback.
718 	 *
719 	 * Return: %TRUE if the task has completed, %FALSE otherwise.
720 	 *
721 	 * Since: 2.44
722 	 */
723 	public bool getCompleted()
724 	{
725 		return g_task_get_completed(gTask) != 0;
726 	}
727 
728 	/**
729 	 * Gets the #GMainContext that @task will return its result in (that
730 	 * is, the context that was the
731 	 * [thread-default main context][g-main-context-push-thread-default]
732 	 * at the point when @task was created).
733 	 *
734 	 * This will always return a non-%NULL value, even if the task's
735 	 * context is the default #GMainContext.
736 	 *
737 	 * Return: @task's #GMainContext
738 	 *
739 	 * Since: 2.36
740 	 */
741 	public MainContext getContext()
742 	{
743 		auto p = g_task_get_context(gTask);
744 		
745 		if(p is null)
746 		{
747 			return null;
748 		}
749 		
750 		return new MainContext(cast(GMainContext*) p);
751 	}
752 
753 	/**
754 	 * Gets @task's priority
755 	 *
756 	 * Return: @task's priority
757 	 *
758 	 * Since: 2.36
759 	 */
760 	public int getPriority()
761 	{
762 		return g_task_get_priority(gTask);
763 	}
764 
765 	/**
766 	 * Gets @task's return-on-cancel flag. See
767 	 * g_task_set_return_on_cancel() for more details.
768 	 *
769 	 * Since: 2.36
770 	 */
771 	public bool getReturnOnCancel()
772 	{
773 		return g_task_get_return_on_cancel(gTask) != 0;
774 	}
775 
776 	/**
777 	 * Gets the source object from @task. Like
778 	 * g_async_result_get_source_object(), but does not ref the object.
779 	 *
780 	 * Return: @task's source object, or %NULL
781 	 *
782 	 * Since: 2.36
783 	 */
784 	public ObjectG getSourceObject()
785 	{
786 		auto p = g_task_get_source_object(gTask);
787 		
788 		if(p is null)
789 		{
790 			return null;
791 		}
792 		
793 		return ObjectG.getDObject!(ObjectG)(cast(GObject*) p);
794 	}
795 
796 	/**
797 	 * Gets @task's source tag. See g_task_set_source_tag().
798 	 *
799 	 * Return: @task's source tag
800 	 *
801 	 * Since: 2.36
802 	 */
803 	public void* getSourceTag()
804 	{
805 		return g_task_get_source_tag(gTask);
806 	}
807 
808 	/**
809 	 * Gets @task's `task_data`.
810 	 *
811 	 * Return: @task's `task_data`.
812 	 *
813 	 * Since: 2.36
814 	 */
815 	public void* getTaskData()
816 	{
817 		return g_task_get_task_data(gTask);
818 	}
819 
820 	/**
821 	 * Tests if @task resulted in an error.
822 	 *
823 	 * Return: %TRUE if the task resulted in an error, %FALSE otherwise.
824 	 *
825 	 * Since: 2.36
826 	 */
827 	public bool hadError()
828 	{
829 		return g_task_had_error(gTask) != 0;
830 	}
831 
832 	/**
833 	 * Gets the result of @task as a #gboolean.
834 	 *
835 	 * If the task resulted in an error, or was cancelled, then this will
836 	 * instead return %FALSE and set @error.
837 	 *
838 	 * Since this method transfers ownership of the return value (or
839 	 * error) to the caller, you may only call it once.
840 	 *
841 	 * Return: the task result, or %FALSE on error
842 	 *
843 	 * Since: 2.36
844 	 *
845 	 * Throws: GException on failure.
846 	 */
847 	public bool propagateBoolean()
848 	{
849 		GError* err = null;
850 		
851 		auto p = g_task_propagate_boolean(gTask, &err) != 0;
852 		
853 		if (err !is null)
854 		{
855 			throw new GException( new ErrorG(err) );
856 		}
857 		
858 		return p;
859 	}
860 
861 	/**
862 	 * Gets the result of @task as an integer (#gssize).
863 	 *
864 	 * If the task resulted in an error, or was cancelled, then this will
865 	 * instead return -1 and set @error.
866 	 *
867 	 * Since this method transfers ownership of the return value (or
868 	 * error) to the caller, you may only call it once.
869 	 *
870 	 * Return: the task result, or -1 on error
871 	 *
872 	 * Since: 2.36
873 	 *
874 	 * Throws: GException on failure.
875 	 */
876 	public ptrdiff_t propagateInt()
877 	{
878 		GError* err = null;
879 		
880 		auto p = g_task_propagate_int(gTask, &err);
881 		
882 		if (err !is null)
883 		{
884 			throw new GException( new ErrorG(err) );
885 		}
886 		
887 		return p;
888 	}
889 
890 	/**
891 	 * Gets the result of @task as a pointer, and transfers ownership
892 	 * of that value to the caller.
893 	 *
894 	 * If the task resulted in an error, or was cancelled, then this will
895 	 * instead return %NULL and set @error.
896 	 *
897 	 * Since this method transfers ownership of the return value (or
898 	 * error) to the caller, you may only call it once.
899 	 *
900 	 * Return: the task result, or %NULL on error
901 	 *
902 	 * Since: 2.36
903 	 *
904 	 * Throws: GException on failure.
905 	 */
906 	public void* propagatePointer()
907 	{
908 		GError* err = null;
909 		
910 		auto p = g_task_propagate_pointer(gTask, &err);
911 		
912 		if (err !is null)
913 		{
914 			throw new GException( new ErrorG(err) );
915 		}
916 		
917 		return p;
918 	}
919 
920 	/**
921 	 * Sets @task's result to @result and completes the task (see
922 	 * g_task_return_pointer() for more discussion of exactly what this
923 	 * means).
924 	 *
925 	 * Params:
926 	 *     result = the #gboolean result of a task function.
927 	 *
928 	 * Since: 2.36
929 	 */
930 	public void returnBoolean(bool result)
931 	{
932 		g_task_return_boolean(gTask, result);
933 	}
934 
935 	/**
936 	 * Sets @task's result to @error (which @task assumes ownership of)
937 	 * and completes the task (see g_task_return_pointer() for more
938 	 * discussion of exactly what this means).
939 	 *
940 	 * Note that since the task takes ownership of @error, and since the
941 	 * task may be completed before returning from g_task_return_error(),
942 	 * you cannot assume that @error is still valid after calling this.
943 	 * Call g_error_copy() on the error if you need to keep a local copy
944 	 * as well.
945 	 *
946 	 * See also g_task_return_new_error().
947 	 *
948 	 * Params:
949 	 *     error = the #GError result of a task function.
950 	 *
951 	 * Since: 2.36
952 	 */
953 	public void returnError(ErrorG error)
954 	{
955 		g_task_return_error(gTask, (error is null) ? null : error.getErrorGStruct());
956 	}
957 
958 	/**
959 	 * Checks if @task's #GCancellable has been cancelled, and if so, sets
960 	 * @task's error accordingly and completes the task (see
961 	 * g_task_return_pointer() for more discussion of exactly what this
962 	 * means).
963 	 *
964 	 * Return: %TRUE if @task has been cancelled, %FALSE if not
965 	 *
966 	 * Since: 2.36
967 	 */
968 	public bool returnErrorIfCancelled()
969 	{
970 		return g_task_return_error_if_cancelled(gTask) != 0;
971 	}
972 
973 	/**
974 	 * Sets @task's result to @result and completes the task (see
975 	 * g_task_return_pointer() for more discussion of exactly what this
976 	 * means).
977 	 *
978 	 * Params:
979 	 *     result = the integer (#gssize) result of a task function.
980 	 *
981 	 * Since: 2.36
982 	 */
983 	public void returnInt(ptrdiff_t result)
984 	{
985 		g_task_return_int(gTask, result);
986 	}
987 
988 	/**
989 	 * Sets @task's result to @result and completes the task. If @result
990 	 * is not %NULL, then @result_destroy will be used to free @result if
991 	 * the caller does not take ownership of it with
992 	 * g_task_propagate_pointer().
993 	 *
994 	 * "Completes the task" means that for an ordinary asynchronous task
995 	 * it will either invoke the task's callback, or else queue that
996 	 * callback to be invoked in the proper #GMainContext, or in the next
997 	 * iteration of the current #GMainContext. For a task run via
998 	 * g_task_run_in_thread() or g_task_run_in_thread_sync(), calling this
999 	 * method will save @result to be returned to the caller later, but
1000 	 * the task will not actually be completed until the #GTaskThreadFunc
1001 	 * exits.
1002 	 *
1003 	 * Note that since the task may be completed before returning from
1004 	 * g_task_return_pointer(), you cannot assume that @result is still
1005 	 * valid after calling this, unless you are still holding another
1006 	 * reference on it.
1007 	 *
1008 	 * Params:
1009 	 *     result = the pointer result of a task
1010 	 *         function
1011 	 *     resultDestroy = a #GDestroyNotify function.
1012 	 *
1013 	 * Since: 2.36
1014 	 */
1015 	public void returnPointer(void* result, GDestroyNotify resultDestroy)
1016 	{
1017 		g_task_return_pointer(gTask, result, resultDestroy);
1018 	}
1019 
1020 	/**
1021 	 * Runs @task_func in another thread. When @task_func returns, @task's
1022 	 * #GAsyncReadyCallback will be invoked in @task's #GMainContext.
1023 	 *
1024 	 * This takes a ref on @task until the task completes.
1025 	 *
1026 	 * See #GTaskThreadFunc for more details about how @task_func is handled.
1027 	 *
1028 	 * Although GLib currently rate-limits the tasks queued via
1029 	 * g_task_run_in_thread(), you should not assume that it will always
1030 	 * do this. If you have a very large number of tasks to run, but don't
1031 	 * want them to all run at once, you should only queue a limited
1032 	 * number of them at a time.
1033 	 *
1034 	 * Params:
1035 	 *     taskFunc = a #GTaskThreadFunc
1036 	 *
1037 	 * Since: 2.36
1038 	 */
1039 	public void runInThread(GTaskThreadFunc taskFunc)
1040 	{
1041 		g_task_run_in_thread(gTask, taskFunc);
1042 	}
1043 
1044 	/**
1045 	 * Runs @task_func in another thread, and waits for it to return or be
1046 	 * cancelled. You can use g_task_propagate_pointer(), etc, afterward
1047 	 * to get the result of @task_func.
1048 	 *
1049 	 * See #GTaskThreadFunc for more details about how @task_func is handled.
1050 	 *
1051 	 * Normally this is used with tasks created with a %NULL
1052 	 * `callback`, but note that even if the task does
1053 	 * have a callback, it will not be invoked when @task_func returns.
1054 	 * #GTask:completed will be set to %TRUE just before this function returns.
1055 	 *
1056 	 * Although GLib currently rate-limits the tasks queued via
1057 	 * g_task_run_in_thread_sync(), you should not assume that it will
1058 	 * always do this. If you have a very large number of tasks to run,
1059 	 * but don't want them to all run at once, you should only queue a
1060 	 * limited number of them at a time.
1061 	 *
1062 	 * Params:
1063 	 *     taskFunc = a #GTaskThreadFunc
1064 	 *
1065 	 * Since: 2.36
1066 	 */
1067 	public void runInThreadSync(GTaskThreadFunc taskFunc)
1068 	{
1069 		g_task_run_in_thread_sync(gTask, taskFunc);
1070 	}
1071 
1072 	/**
1073 	 * Sets or clears @task's check-cancellable flag. If this is %TRUE
1074 	 * (the default), then g_task_propagate_pointer(), etc, and
1075 	 * g_task_had_error() will check the task's #GCancellable first, and
1076 	 * if it has been cancelled, then they will consider the task to have
1077 	 * returned an "Operation was cancelled" error
1078 	 * (%G_IO_ERROR_CANCELLED), regardless of any other error or return
1079 	 * value the task may have had.
1080 	 *
1081 	 * If @check_cancellable is %FALSE, then the #GTask will not check the
1082 	 * cancellable itself, and it is up to @task's owner to do this (eg,
1083 	 * via g_task_return_error_if_cancelled()).
1084 	 *
1085 	 * If you are using g_task_set_return_on_cancel() as well, then
1086 	 * you must leave check-cancellable set %TRUE.
1087 	 *
1088 	 * Params:
1089 	 *     checkCancellable = whether #GTask will check the state of
1090 	 *         its #GCancellable for you.
1091 	 *
1092 	 * Since: 2.36
1093 	 */
1094 	public void setCheckCancellable(bool checkCancellable)
1095 	{
1096 		g_task_set_check_cancellable(gTask, checkCancellable);
1097 	}
1098 
1099 	/**
1100 	 * Sets @task's priority. If you do not call this, it will default to
1101 	 * %G_PRIORITY_DEFAULT.
1102 	 *
1103 	 * This will affect the priority of #GSources created with
1104 	 * g_task_attach_source() and the scheduling of tasks run in threads,
1105 	 * and can also be explicitly retrieved later via
1106 	 * g_task_get_priority().
1107 	 *
1108 	 * Params:
1109 	 *     priority = the [priority][io-priority] of the request
1110 	 *
1111 	 * Since: 2.36
1112 	 */
1113 	public void setPriority(int priority)
1114 	{
1115 		g_task_set_priority(gTask, priority);
1116 	}
1117 
1118 	/**
1119 	 * Sets or clears @task's return-on-cancel flag. This is only
1120 	 * meaningful for tasks run via g_task_run_in_thread() or
1121 	 * g_task_run_in_thread_sync().
1122 	 *
1123 	 * If @return_on_cancel is %TRUE, then cancelling @task's
1124 	 * #GCancellable will immediately cause it to return, as though the
1125 	 * task's #GTaskThreadFunc had called
1126 	 * g_task_return_error_if_cancelled() and then returned.
1127 	 *
1128 	 * This allows you to create a cancellable wrapper around an
1129 	 * uninterruptable function. The #GTaskThreadFunc just needs to be
1130 	 * careful that it does not modify any externally-visible state after
1131 	 * it has been cancelled. To do that, the thread should call
1132 	 * g_task_set_return_on_cancel() again to (atomically) set
1133 	 * return-on-cancel %FALSE before making externally-visible changes;
1134 	 * if the task gets cancelled before the return-on-cancel flag could
1135 	 * be changed, g_task_set_return_on_cancel() will indicate this by
1136 	 * returning %FALSE.
1137 	 *
1138 	 * You can disable and re-enable this flag multiple times if you wish.
1139 	 * If the task's #GCancellable is cancelled while return-on-cancel is
1140 	 * %FALSE, then calling g_task_set_return_on_cancel() to set it %TRUE
1141 	 * again will cause the task to be cancelled at that point.
1142 	 *
1143 	 * If the task's #GCancellable is already cancelled before you call
1144 	 * g_task_run_in_thread()/g_task_run_in_thread_sync(), then the
1145 	 * #GTaskThreadFunc will still be run (for consistency), but the task
1146 	 * will also be completed right away.
1147 	 *
1148 	 * Params:
1149 	 *     returnOnCancel = whether the task returns automatically when
1150 	 *         it is cancelled.
1151 	 *
1152 	 * Return: %TRUE if @task's return-on-cancel flag was changed to
1153 	 *     match @return_on_cancel. %FALSE if @task has already been
1154 	 *     cancelled.
1155 	 *
1156 	 * Since: 2.36
1157 	 */
1158 	public bool setReturnOnCancel(bool returnOnCancel)
1159 	{
1160 		return g_task_set_return_on_cancel(gTask, returnOnCancel) != 0;
1161 	}
1162 
1163 	/**
1164 	 * Sets @task's source tag. You can use this to tag a task return
1165 	 * value with a particular pointer (usually a pointer to the function
1166 	 * doing the tagging) and then later check it using
1167 	 * g_task_get_source_tag() (or g_async_result_is_tagged()) in the
1168 	 * task's "finish" function, to figure out if the response came from a
1169 	 * particular place.
1170 	 *
1171 	 * Params:
1172 	 *     sourceTag = an opaque pointer indicating the source of this task
1173 	 *
1174 	 * Since: 2.36
1175 	 */
1176 	public void setSourceTag(void* sourceTag)
1177 	{
1178 		g_task_set_source_tag(gTask, sourceTag);
1179 	}
1180 
1181 	/**
1182 	 * Sets @task's task data (freeing the existing task data, if any).
1183 	 *
1184 	 * Params:
1185 	 *     taskData = task-specific data
1186 	 *     taskDataDestroy = #GDestroyNotify for @task_data
1187 	 *
1188 	 * Since: 2.36
1189 	 */
1190 	public void setTaskData(void* taskData, GDestroyNotify taskDataDestroy)
1191 	{
1192 		g_task_set_task_data(gTask, taskData, taskDataDestroy);
1193 	}
1194 }