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 gio.c.functions;
31 public  import gio.c.types;
32 private import glib.ConstructionException;
33 private import glib.ErrorG;
34 private import glib.GException;
35 private import glib.MainContext;
36 private import glib.Source;
37 private import glib.Str;
38 private import gobject.ObjectG;
39 public  import gtkc.giotypes;
40 
41 
42 /**
43  * A #GTask represents and manages a cancellable "task".
44  * 
45  * ## Asynchronous operations
46  * 
47  * The most common usage of #GTask is as a #GAsyncResult, to
48  * manage data during an asynchronous operation. You call
49  * g_task_new() in the "start" method, followed by
50  * g_task_set_task_data() and the like if you need to keep some
51  * additional data associated with the task, and then pass the
52  * task object around through your asynchronous operation.
53  * Eventually, you will call a method such as
54  * g_task_return_pointer() or g_task_return_error(), which will
55  * save the value you give it and then invoke the task's callback
56  * function in the
57  * [thread-default main context][g-main-context-push-thread-default]
58  * where it was created (waiting until the next iteration of the main
59  * loop first, if necessary). The caller will pass the #GTask back to
60  * the operation's finish function (as a #GAsyncResult), and you can
61  * use g_task_propagate_pointer() or the like to extract the
62  * return value.
63  * 
64  * Here is an example for using GTask as a GAsyncResult:
65  * |[<!-- language="C" -->
66  * typedef struct {
67  * CakeFrostingType frosting;
68  * char *message;
69  * } DecorationData;
70  * 
71  * static void
72  * decoration_data_free (DecorationData *decoration)
73  * {
74  * g_free (decoration->message);
75  * g_slice_free (DecorationData, decoration);
76  * }
77  * 
78  * static void
79  * baked_cb (Cake     *cake,
80  * gpointer  user_data)
81  * {
82  * GTask *task = user_data;
83  * DecorationData *decoration = g_task_get_task_data (task);
84  * GError *error = NULL;
85  * 
86  * if (cake == NULL)
87  * {
88  * g_task_return_new_error (task, BAKER_ERROR, BAKER_ERROR_NO_FLOUR,
89  * "Go to the supermarket");
90  * g_object_unref (task);
91  * return;
92  * }
93  * 
94  * if (!cake_decorate (cake, decoration->frosting, decoration->message, &error))
95  * {
96  * g_object_unref (cake);
97  * // g_task_return_error() takes ownership of error
98  * g_task_return_error (task, error);
99  * g_object_unref (task);
100  * return;
101  * }
102  * 
103  * g_task_return_pointer (task, cake, g_object_unref);
104  * g_object_unref (task);
105  * }
106  * 
107  * void
108  * baker_bake_cake_async (Baker               *self,
109  * guint                radius,
110  * CakeFlavor           flavor,
111  * CakeFrostingType     frosting,
112  * const char          *message,
113  * GCancellable        *cancellable,
114  * GAsyncReadyCallback  callback,
115  * gpointer             user_data)
116  * {
117  * GTask *task;
118  * DecorationData *decoration;
119  * Cake  *cake;
120  * 
121  * task = g_task_new (self, cancellable, callback, user_data);
122  * if (radius < 3)
123  * {
124  * g_task_return_new_error (task, BAKER_ERROR, BAKER_ERROR_TOO_SMALL,
125  * "%ucm radius cakes are silly",
126  * radius);
127  * g_object_unref (task);
128  * return;
129  * }
130  * 
131  * cake = _baker_get_cached_cake (self, radius, flavor, frosting, message);
132  * if (cake != NULL)
133  * {
134  * // _baker_get_cached_cake() returns a reffed cake
135  * g_task_return_pointer (task, cake, g_object_unref);
136  * g_object_unref (task);
137  * return;
138  * }
139  * 
140  * decoration = g_slice_new (DecorationData);
141  * decoration->frosting = frosting;
142  * decoration->message = g_strdup (message);
143  * g_task_set_task_data (task, decoration, (GDestroyNotify) decoration_data_free);
144  * 
145  * _baker_begin_cake (self, radius, flavor, cancellable, baked_cb, task);
146  * }
147  * 
148  * Cake *
149  * baker_bake_cake_finish (Baker         *self,
150  * GAsyncResult  *result,
151  * GError       **error)
152  * {
153  * g_return_val_if_fail (g_task_is_valid (result, self), NULL);
154  * 
155  * return g_task_propagate_pointer (G_TASK (result), error);
156  * }
157  * ]|
158  * 
159  * ## Chained asynchronous operations
160  * 
161  * #GTask also tries to simplify asynchronous operations that
162  * internally chain together several smaller asynchronous
163  * operations. g_task_get_cancellable(), g_task_get_context(),
164  * and g_task_get_priority() allow you to get back the task's
165  * #GCancellable, #GMainContext, and [I/O priority][io-priority]
166  * when starting a new subtask, so you don't have to keep track
167  * of them yourself. g_task_attach_source() simplifies the case
168  * of waiting for a source to fire (automatically using the correct
169  * #GMainContext and priority).
170  * 
171  * Here is an example for chained asynchronous operations:
172  * |[<!-- language="C" -->
173  * typedef struct {
174  * Cake *cake;
175  * CakeFrostingType frosting;
176  * char *message;
177  * } BakingData;
178  * 
179  * static void
180  * decoration_data_free (BakingData *bd)
181  * {
182  * if (bd->cake)
183  * g_object_unref (bd->cake);
184  * g_free (bd->message);
185  * g_slice_free (BakingData, bd);
186  * }
187  * 
188  * static void
189  * decorated_cb (Cake         *cake,
190  * GAsyncResult *result,
191  * gpointer      user_data)
192  * {
193  * GTask *task = user_data;
194  * GError *error = NULL;
195  * 
196  * if (!cake_decorate_finish (cake, result, &error))
197  * {
198  * g_object_unref (cake);
199  * g_task_return_error (task, error);
200  * g_object_unref (task);
201  * return;
202  * }
203  * 
204  * // baking_data_free() will drop its ref on the cake, so we have to
205  * // take another here to give to the caller.
206  * g_task_return_pointer (task, g_object_ref (cake), g_object_unref);
207  * g_object_unref (task);
208  * }
209  * 
210  * static gboolean
211  * decorator_ready (gpointer user_data)
212  * {
213  * GTask *task = user_data;
214  * BakingData *bd = g_task_get_task_data (task);
215  * 
216  * cake_decorate_async (bd->cake, bd->frosting, bd->message,
217  * g_task_get_cancellable (task),
218  * decorated_cb, task);
219  * 
220  * return G_SOURCE_REMOVE;
221  * }
222  * 
223  * static void
224  * baked_cb (Cake     *cake,
225  * gpointer  user_data)
226  * {
227  * GTask *task = user_data;
228  * BakingData *bd = g_task_get_task_data (task);
229  * GError *error = NULL;
230  * 
231  * if (cake == NULL)
232  * {
233  * g_task_return_new_error (task, BAKER_ERROR, BAKER_ERROR_NO_FLOUR,
234  * "Go to the supermarket");
235  * g_object_unref (task);
236  * return;
237  * }
238  * 
239  * bd->cake = cake;
240  * 
241  * // Bail out now if the user has already cancelled
242  * if (g_task_return_error_if_cancelled (task))
243  * {
244  * g_object_unref (task);
245  * return;
246  * }
247  * 
248  * if (cake_decorator_available (cake))
249  * decorator_ready (task);
250  * else
251  * {
252  * GSource *source;
253  * 
254  * source = cake_decorator_wait_source_new (cake);
255  * // Attach @source to @task's GMainContext and have it call
256  * // decorator_ready() when it is ready.
257  * g_task_attach_source (task, source, decorator_ready);
258  * g_source_unref (source);
259  * }
260  * }
261  * 
262  * void
263  * baker_bake_cake_async (Baker               *self,
264  * guint                radius,
265  * CakeFlavor           flavor,
266  * CakeFrostingType     frosting,
267  * const char          *message,
268  * gint                 priority,
269  * GCancellable        *cancellable,
270  * GAsyncReadyCallback  callback,
271  * gpointer             user_data)
272  * {
273  * GTask *task;
274  * BakingData *bd;
275  * 
276  * task = g_task_new (self, cancellable, callback, user_data);
277  * g_task_set_priority (task, priority);
278  * 
279  * bd = g_slice_new0 (BakingData);
280  * bd->frosting = frosting;
281  * bd->message = g_strdup (message);
282  * g_task_set_task_data (task, bd, (GDestroyNotify) baking_data_free);
283  * 
284  * _baker_begin_cake (self, radius, flavor, cancellable, baked_cb, task);
285  * }
286  * 
287  * Cake *
288  * baker_bake_cake_finish (Baker         *self,
289  * GAsyncResult  *result,
290  * GError       **error)
291  * {
292  * g_return_val_if_fail (g_task_is_valid (result, self), NULL);
293  * 
294  * return g_task_propagate_pointer (G_TASK (result), error);
295  * }
296  * ]|
297  * 
298  * ## Asynchronous operations from synchronous ones
299  * 
300  * You can use g_task_run_in_thread() to turn a synchronous
301  * operation into an asynchronous one, by running it in a thread.
302  * When it completes, the result will be dispatched to the
303  * [thread-default main context][g-main-context-push-thread-default]
304  * where the #GTask was created.
305  * 
306  * Running a task in a thread:
307  * |[<!-- language="C" -->
308  * typedef struct {
309  * guint radius;
310  * CakeFlavor flavor;
311  * CakeFrostingType frosting;
312  * char *message;
313  * } CakeData;
314  * 
315  * static void
316  * cake_data_free (CakeData *cake_data)
317  * {
318  * g_free (cake_data->message);
319  * g_slice_free (CakeData, cake_data);
320  * }
321  * 
322  * static void
323  * bake_cake_thread (GTask         *task,
324  * gpointer       source_object,
325  * gpointer       task_data,
326  * GCancellable  *cancellable)
327  * {
328  * Baker *self = source_object;
329  * CakeData *cake_data = task_data;
330  * Cake *cake;
331  * GError *error = NULL;
332  * 
333  * cake = bake_cake (baker, cake_data->radius, cake_data->flavor,
334  * cake_data->frosting, cake_data->message,
335  * cancellable, &error);
336  * if (cake)
337  * g_task_return_pointer (task, cake, g_object_unref);
338  * else
339  * g_task_return_error (task, error);
340  * }
341  * 
342  * void
343  * baker_bake_cake_async (Baker               *self,
344  * guint                radius,
345  * CakeFlavor           flavor,
346  * CakeFrostingType     frosting,
347  * const char          *message,
348  * GCancellable        *cancellable,
349  * GAsyncReadyCallback  callback,
350  * gpointer             user_data)
351  * {
352  * CakeData *cake_data;
353  * GTask *task;
354  * 
355  * cake_data = g_slice_new (CakeData);
356  * cake_data->radius = radius;
357  * cake_data->flavor = flavor;
358  * cake_data->frosting = frosting;
359  * cake_data->message = g_strdup (message);
360  * task = g_task_new (self, cancellable, callback, user_data);
361  * g_task_set_task_data (task, cake_data, (GDestroyNotify) cake_data_free);
362  * g_task_run_in_thread (task, bake_cake_thread);
363  * g_object_unref (task);
364  * }
365  * 
366  * Cake *
367  * baker_bake_cake_finish (Baker         *self,
368  * GAsyncResult  *result,
369  * GError       **error)
370  * {
371  * g_return_val_if_fail (g_task_is_valid (result, self), NULL);
372  * 
373  * return g_task_propagate_pointer (G_TASK (result), error);
374  * }
375  * ]|
376  * 
377  * ## Adding cancellability to uncancellable tasks
378  * 
379  * Finally, g_task_run_in_thread() and g_task_run_in_thread_sync()
380  * can be used to turn an uncancellable operation into a
381  * cancellable one. If you call g_task_set_return_on_cancel(),
382  * passing %TRUE, then if the task's #GCancellable is cancelled,
383  * it will return control back to the caller immediately, while
384  * allowing the task thread to continue running in the background
385  * (and simply discarding its result when it finally does finish).
386  * Provided that the task thread is careful about how it uses
387  * locks and other externally-visible resources, this allows you
388  * to make "GLib-friendly" asynchronous and cancellable
389  * synchronous variants of blocking APIs.
390  * 
391  * Cancelling a task:
392  * |[<!-- language="C" -->
393  * static void
394  * bake_cake_thread (GTask         *task,
395  * gpointer       source_object,
396  * gpointer       task_data,
397  * GCancellable  *cancellable)
398  * {
399  * Baker *self = source_object;
400  * CakeData *cake_data = task_data;
401  * Cake *cake;
402  * GError *error = NULL;
403  * 
404  * cake = bake_cake (baker, cake_data->radius, cake_data->flavor,
405  * cake_data->frosting, cake_data->message,
406  * &error);
407  * if (error)
408  * {
409  * g_task_return_error (task, error);
410  * return;
411  * }
412  * 
413  * // If the task has already been cancelled, then we don't want to add
414  * // the cake to the cake cache. Likewise, we don't  want to have the
415  * // task get cancelled in the middle of updating the cache.
416  * // g_task_set_return_on_cancel() will return %TRUE here if it managed
417  * // to disable return-on-cancel, or %FALSE if the task was cancelled
418  * // before it could.
419  * if (g_task_set_return_on_cancel (task, FALSE))
420  * {
421  * // If the caller cancels at this point, their
422  * // GAsyncReadyCallback won't be invoked until we return,
423  * // so we don't have to worry that this code will run at
424  * // the same time as that code does. But if there were
425  * // other functions that might look at the cake cache,
426  * // then we'd probably need a GMutex here as well.
427  * baker_add_cake_to_cache (baker, cake);
428  * g_task_return_pointer (task, cake, g_object_unref);
429  * }
430  * }
431  * 
432  * void
433  * baker_bake_cake_async (Baker               *self,
434  * guint                radius,
435  * CakeFlavor           flavor,
436  * CakeFrostingType     frosting,
437  * const char          *message,
438  * GCancellable        *cancellable,
439  * GAsyncReadyCallback  callback,
440  * gpointer             user_data)
441  * {
442  * CakeData *cake_data;
443  * GTask *task;
444  * 
445  * cake_data = g_slice_new (CakeData);
446  * 
447  * ...
448  * 
449  * task = g_task_new (self, cancellable, callback, user_data);
450  * g_task_set_task_data (task, cake_data, (GDestroyNotify) cake_data_free);
451  * g_task_set_return_on_cancel (task, TRUE);
452  * g_task_run_in_thread (task, bake_cake_thread);
453  * }
454  * 
455  * Cake *
456  * baker_bake_cake_sync (Baker               *self,
457  * guint                radius,
458  * CakeFlavor           flavor,
459  * CakeFrostingType     frosting,
460  * const char          *message,
461  * GCancellable        *cancellable,
462  * GError             **error)
463  * {
464  * CakeData *cake_data;
465  * GTask *task;
466  * Cake *cake;
467  * 
468  * cake_data = g_slice_new (CakeData);
469  * 
470  * ...
471  * 
472  * task = g_task_new (self, cancellable, NULL, NULL);
473  * g_task_set_task_data (task, cake_data, (GDestroyNotify) cake_data_free);
474  * g_task_set_return_on_cancel (task, TRUE);
475  * g_task_run_in_thread_sync (task, bake_cake_thread);
476  * 
477  * cake = g_task_propagate_pointer (task, error);
478  * g_object_unref (task);
479  * return cake;
480  * }
481  * ]|
482  * 
483  * ## Porting from GSimpleAsyncResult
484  * 
485  * #GTask's API attempts to be simpler than #GSimpleAsyncResult's
486  * in several ways:
487  * - You can save task-specific data with g_task_set_task_data(), and
488  * retrieve it later with g_task_get_task_data(). This replaces the
489  * abuse of g_simple_async_result_set_op_res_gpointer() for the same
490  * purpose with #GSimpleAsyncResult.
491  * - In addition to the task data, #GTask also keeps track of the
492  * [priority][io-priority], #GCancellable, and
493  * #GMainContext associated with the task, so tasks that consist of
494  * a chain of simpler asynchronous operations will have easy access
495  * to those values when starting each sub-task.
496  * - g_task_return_error_if_cancelled() provides simplified
497  * handling for cancellation. In addition, cancellation
498  * overrides any other #GTask return value by default, like
499  * #GSimpleAsyncResult does when
500  * g_simple_async_result_set_check_cancellable() is called.
501  * (You can use g_task_set_check_cancellable() to turn off that
502  * behavior.) On the other hand, g_task_run_in_thread()
503  * guarantees that it will always run your
504  * `task_func`, even if the task's #GCancellable
505  * is already cancelled before the task gets a chance to run;
506  * you can start your `task_func` with a
507  * g_task_return_error_if_cancelled() check if you need the
508  * old behavior.
509  * - The "return" methods (eg, g_task_return_pointer())
510  * automatically cause the task to be "completed" as well, and
511  * there is no need to worry about the "complete" vs "complete
512  * in idle" distinction. (#GTask automatically figures out
513  * whether the task's callback can be invoked directly, or
514  * if it needs to be sent to another #GMainContext, or delayed
515  * until the next iteration of the current #GMainContext.)
516  * - The "finish" functions for #GTask based operations are generally
517  * much simpler than #GSimpleAsyncResult ones, normally consisting
518  * of only a single call to g_task_propagate_pointer() or the like.
519  * Since g_task_propagate_pointer() "steals" the return value from
520  * the #GTask, it is not necessary to juggle pointers around to
521  * prevent it from being freed twice.
522  * - With #GSimpleAsyncResult, it was common to call
523  * g_simple_async_result_propagate_error() from the
524  * `_finish()` wrapper function, and have
525  * virtual method implementations only deal with successful
526  * returns. This behavior is deprecated, because it makes it
527  * difficult for a subclass to chain to a parent class's async
528  * methods. Instead, the wrapper function should just be a
529  * simple wrapper, and the virtual method should call an
530  * appropriate `g_task_propagate_` function.
531  * Note that wrapper methods can now use
532  * g_async_result_legacy_propagate_error() to do old-style
533  * #GSimpleAsyncResult error-returning behavior, and
534  * g_async_result_is_tagged() to check if a result is tagged as
535  * having come from the `_async()` wrapper
536  * function (for "short-circuit" results, such as when passing
537  * 0 to g_input_stream_read_async()).
538  */
539 public class Task : ObjectG, AsyncResultIF
540 {
541 	/** the main Gtk struct */
542 	protected GTask* gTask;
543 
544 	/** Get the main Gtk struct */
545 	public GTask* getTaskStruct(bool transferOwnership = false)
546 	{
547 		if (transferOwnership)
548 			ownedRef = false;
549 		return gTask;
550 	}
551 
552 	/** the main Gtk struct as a void* */
553 	protected override void* getStruct()
554 	{
555 		return cast(void*)gTask;
556 	}
557 
558 	/**
559 	 * Sets our main struct and passes it to the parent class.
560 	 */
561 	public this (GTask* gTask, bool ownedRef = false)
562 	{
563 		this.gTask = gTask;
564 		super(cast(GObject*)gTask, ownedRef);
565 	}
566 
567 	// add the AsyncResult capabilities
568 	mixin AsyncResultT!(GTask);
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 	 * Returns: 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 	 * Returns: %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(true));
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 	 * It will set the @source’s name to the task’s name (as set with
672 	 * g_task_set_name()), if one has been set.
673 	 *
674 	 * This takes a reference on @task until @source is destroyed.
675 	 *
676 	 * Params:
677 	 *     source = the source to attach
678 	 *     callback = the callback to invoke when @source triggers
679 	 *
680 	 * Since: 2.36
681 	 */
682 	public void attachSource(Source source, GSourceFunc callback)
683 	{
684 		g_task_attach_source(gTask, (source is null) ? null : source.getSourceStruct(), callback);
685 	}
686 
687 	/**
688 	 * Gets @task's #GCancellable
689 	 *
690 	 * Returns: @task's #GCancellable
691 	 *
692 	 * Since: 2.36
693 	 */
694 	public Cancellable getCancellable()
695 	{
696 		auto p = g_task_get_cancellable(gTask);
697 
698 		if(p is null)
699 		{
700 			return null;
701 		}
702 
703 		return ObjectG.getDObject!(Cancellable)(cast(GCancellable*) p);
704 	}
705 
706 	/**
707 	 * Gets @task's check-cancellable flag. See
708 	 * g_task_set_check_cancellable() for more details.
709 	 *
710 	 * Since: 2.36
711 	 */
712 	public bool getCheckCancellable()
713 	{
714 		return g_task_get_check_cancellable(gTask) != 0;
715 	}
716 
717 	/**
718 	 * Gets the value of #GTask:completed. This changes from %FALSE to %TRUE after
719 	 * the task’s callback is invoked, and will return %FALSE if called from inside
720 	 * the callback.
721 	 *
722 	 * Returns: %TRUE if the task has completed, %FALSE otherwise.
723 	 *
724 	 * Since: 2.44
725 	 */
726 	public bool getCompleted()
727 	{
728 		return g_task_get_completed(gTask) != 0;
729 	}
730 
731 	/**
732 	 * Gets the #GMainContext that @task will return its result in (that
733 	 * is, the context that was the
734 	 * [thread-default main context][g-main-context-push-thread-default]
735 	 * at the point when @task was created).
736 	 *
737 	 * This will always return a non-%NULL value, even if the task's
738 	 * context is the default #GMainContext.
739 	 *
740 	 * Returns: @task's #GMainContext
741 	 *
742 	 * Since: 2.36
743 	 */
744 	public MainContext getContext()
745 	{
746 		auto p = g_task_get_context(gTask);
747 
748 		if(p is null)
749 		{
750 			return null;
751 		}
752 
753 		return new MainContext(cast(GMainContext*) p);
754 	}
755 
756 	/**
757 	 * Gets @task’s name. See g_task_set_name().
758 	 *
759 	 * Returns: @task’s name, or %NULL
760 	 *
761 	 * Since: 2.60
762 	 */
763 	public string getName()
764 	{
765 		return Str.toString(g_task_get_name(gTask));
766 	}
767 
768 	/**
769 	 * Gets @task's priority
770 	 *
771 	 * Returns: @task's priority
772 	 *
773 	 * Since: 2.36
774 	 */
775 	public int getPriority()
776 	{
777 		return g_task_get_priority(gTask);
778 	}
779 
780 	/**
781 	 * Gets @task's return-on-cancel flag. See
782 	 * g_task_set_return_on_cancel() for more details.
783 	 *
784 	 * Since: 2.36
785 	 */
786 	public bool getReturnOnCancel()
787 	{
788 		return g_task_get_return_on_cancel(gTask) != 0;
789 	}
790 
791 	/**
792 	 * Gets the source object from @task. Like
793 	 * g_async_result_get_source_object(), but does not ref the object.
794 	 *
795 	 * Returns: @task's source object, or %NULL
796 	 *
797 	 * Since: 2.36
798 	 */
799 	public ObjectG getSourceObject()
800 	{
801 		auto p = g_task_get_source_object(gTask);
802 
803 		if(p is null)
804 		{
805 			return null;
806 		}
807 
808 		return ObjectG.getDObject!(ObjectG)(cast(GObject*) p);
809 	}
810 
811 	/**
812 	 * Gets @task's source tag. See g_task_set_source_tag().
813 	 *
814 	 * Returns: @task's source tag
815 	 *
816 	 * Since: 2.36
817 	 */
818 	public void* getSourceTag()
819 	{
820 		return g_task_get_source_tag(gTask);
821 	}
822 
823 	/**
824 	 * Gets @task's `task_data`.
825 	 *
826 	 * Returns: @task's `task_data`.
827 	 *
828 	 * Since: 2.36
829 	 */
830 	public void* getTaskData()
831 	{
832 		return g_task_get_task_data(gTask);
833 	}
834 
835 	/**
836 	 * Tests if @task resulted in an error.
837 	 *
838 	 * Returns: %TRUE if the task resulted in an error, %FALSE otherwise.
839 	 *
840 	 * Since: 2.36
841 	 */
842 	public bool hadError()
843 	{
844 		return g_task_had_error(gTask) != 0;
845 	}
846 
847 	/**
848 	 * Gets the result of @task as a #gboolean.
849 	 *
850 	 * If the task resulted in an error, or was cancelled, then this will
851 	 * instead return %FALSE and set @error.
852 	 *
853 	 * Since this method transfers ownership of the return value (or
854 	 * error) to the caller, you may only call it once.
855 	 *
856 	 * Returns: the task result, or %FALSE on error
857 	 *
858 	 * Since: 2.36
859 	 *
860 	 * Throws: GException on failure.
861 	 */
862 	public bool propagateBoolean()
863 	{
864 		GError* err = null;
865 
866 		auto p = g_task_propagate_boolean(gTask, &err) != 0;
867 
868 		if (err !is null)
869 		{
870 			throw new GException( new ErrorG(err) );
871 		}
872 
873 		return p;
874 	}
875 
876 	/**
877 	 * Gets the result of @task as an integer (#gssize).
878 	 *
879 	 * If the task resulted in an error, or was cancelled, then this will
880 	 * instead return -1 and set @error.
881 	 *
882 	 * Since this method transfers ownership of the return value (or
883 	 * error) to the caller, you may only call it once.
884 	 *
885 	 * Returns: the task result, or -1 on error
886 	 *
887 	 * Since: 2.36
888 	 *
889 	 * Throws: GException on failure.
890 	 */
891 	public ptrdiff_t propagateInt()
892 	{
893 		GError* err = null;
894 
895 		auto p = g_task_propagate_int(gTask, &err);
896 
897 		if (err !is null)
898 		{
899 			throw new GException( new ErrorG(err) );
900 		}
901 
902 		return p;
903 	}
904 
905 	/**
906 	 * Gets the result of @task as a pointer, and transfers ownership
907 	 * of that value to the caller.
908 	 *
909 	 * If the task resulted in an error, or was cancelled, then this will
910 	 * instead return %NULL and set @error.
911 	 *
912 	 * Since this method transfers ownership of the return value (or
913 	 * error) to the caller, you may only call it once.
914 	 *
915 	 * Returns: the task result, or %NULL on error
916 	 *
917 	 * Since: 2.36
918 	 *
919 	 * Throws: GException on failure.
920 	 */
921 	public void* propagatePointer()
922 	{
923 		GError* err = null;
924 
925 		auto p = g_task_propagate_pointer(gTask, &err);
926 
927 		if (err !is null)
928 		{
929 			throw new GException( new ErrorG(err) );
930 		}
931 
932 		return p;
933 	}
934 
935 	/**
936 	 * Sets @task's result to @result and completes the task (see
937 	 * g_task_return_pointer() for more discussion of exactly what this
938 	 * means).
939 	 *
940 	 * Params:
941 	 *     result = the #gboolean result of a task function.
942 	 *
943 	 * Since: 2.36
944 	 */
945 	public void returnBoolean(bool result)
946 	{
947 		g_task_return_boolean(gTask, result);
948 	}
949 
950 	/**
951 	 * Sets @task's result to @error (which @task assumes ownership of)
952 	 * and completes the task (see g_task_return_pointer() for more
953 	 * discussion of exactly what this means).
954 	 *
955 	 * Note that since the task takes ownership of @error, and since the
956 	 * task may be completed before returning from g_task_return_error(),
957 	 * you cannot assume that @error is still valid after calling this.
958 	 * Call g_error_copy() on the error if you need to keep a local copy
959 	 * as well.
960 	 *
961 	 * See also g_task_return_new_error().
962 	 *
963 	 * Params:
964 	 *     error = the #GError result of a task function.
965 	 *
966 	 * Since: 2.36
967 	 */
968 	public void returnError(ErrorG error)
969 	{
970 		g_task_return_error(gTask, (error is null) ? null : error.getErrorGStruct(true));
971 	}
972 
973 	/**
974 	 * Checks if @task's #GCancellable has been cancelled, and if so, sets
975 	 * @task's error accordingly and completes the task (see
976 	 * g_task_return_pointer() for more discussion of exactly what this
977 	 * means).
978 	 *
979 	 * Returns: %TRUE if @task has been cancelled, %FALSE if not
980 	 *
981 	 * Since: 2.36
982 	 */
983 	public bool returnErrorIfCancelled()
984 	{
985 		return g_task_return_error_if_cancelled(gTask) != 0;
986 	}
987 
988 	/**
989 	 * Sets @task's result to @result and completes the task (see
990 	 * g_task_return_pointer() for more discussion of exactly what this
991 	 * means).
992 	 *
993 	 * Params:
994 	 *     result = the integer (#gssize) result of a task function.
995 	 *
996 	 * Since: 2.36
997 	 */
998 	public void returnInt(ptrdiff_t result)
999 	{
1000 		g_task_return_int(gTask, result);
1001 	}
1002 
1003 	/**
1004 	 * Sets @task's result to @result and completes the task. If @result
1005 	 * is not %NULL, then @result_destroy will be used to free @result if
1006 	 * the caller does not take ownership of it with
1007 	 * g_task_propagate_pointer().
1008 	 *
1009 	 * "Completes the task" means that for an ordinary asynchronous task
1010 	 * it will either invoke the task's callback, or else queue that
1011 	 * callback to be invoked in the proper #GMainContext, or in the next
1012 	 * iteration of the current #GMainContext. For a task run via
1013 	 * g_task_run_in_thread() or g_task_run_in_thread_sync(), calling this
1014 	 * method will save @result to be returned to the caller later, but
1015 	 * the task will not actually be completed until the #GTaskThreadFunc
1016 	 * exits.
1017 	 *
1018 	 * Note that since the task may be completed before returning from
1019 	 * g_task_return_pointer(), you cannot assume that @result is still
1020 	 * valid after calling this, unless you are still holding another
1021 	 * reference on it.
1022 	 *
1023 	 * Params:
1024 	 *     result = the pointer result of a task
1025 	 *         function
1026 	 *     resultDestroy = a #GDestroyNotify function.
1027 	 *
1028 	 * Since: 2.36
1029 	 */
1030 	public void returnPointer(void* result, GDestroyNotify resultDestroy)
1031 	{
1032 		g_task_return_pointer(gTask, result, resultDestroy);
1033 	}
1034 
1035 	/**
1036 	 * Runs @task_func in another thread. When @task_func returns, @task's
1037 	 * #GAsyncReadyCallback will be invoked in @task's #GMainContext.
1038 	 *
1039 	 * This takes a ref on @task until the task completes.
1040 	 *
1041 	 * See #GTaskThreadFunc for more details about how @task_func is handled.
1042 	 *
1043 	 * Although GLib currently rate-limits the tasks queued via
1044 	 * g_task_run_in_thread(), you should not assume that it will always
1045 	 * do this. If you have a very large number of tasks to run, but don't
1046 	 * want them to all run at once, you should only queue a limited
1047 	 * number of them at a time.
1048 	 *
1049 	 * Params:
1050 	 *     taskFunc = a #GTaskThreadFunc
1051 	 *
1052 	 * Since: 2.36
1053 	 */
1054 	public void runInThread(GTaskThreadFunc taskFunc)
1055 	{
1056 		g_task_run_in_thread(gTask, taskFunc);
1057 	}
1058 
1059 	/**
1060 	 * Runs @task_func in another thread, and waits for it to return or be
1061 	 * cancelled. You can use g_task_propagate_pointer(), etc, afterward
1062 	 * to get the result of @task_func.
1063 	 *
1064 	 * See #GTaskThreadFunc for more details about how @task_func is handled.
1065 	 *
1066 	 * Normally this is used with tasks created with a %NULL
1067 	 * `callback`, but note that even if the task does
1068 	 * have a callback, it will not be invoked when @task_func returns.
1069 	 * #GTask:completed will be set to %TRUE just before this function returns.
1070 	 *
1071 	 * Although GLib currently rate-limits the tasks queued via
1072 	 * g_task_run_in_thread_sync(), you should not assume that it will
1073 	 * always do this. If you have a very large number of tasks to run,
1074 	 * but don't want them to all run at once, you should only queue a
1075 	 * limited number of them at a time.
1076 	 *
1077 	 * Params:
1078 	 *     taskFunc = a #GTaskThreadFunc
1079 	 *
1080 	 * Since: 2.36
1081 	 */
1082 	public void runInThreadSync(GTaskThreadFunc taskFunc)
1083 	{
1084 		g_task_run_in_thread_sync(gTask, taskFunc);
1085 	}
1086 
1087 	/**
1088 	 * Sets or clears @task's check-cancellable flag. If this is %TRUE
1089 	 * (the default), then g_task_propagate_pointer(), etc, and
1090 	 * g_task_had_error() will check the task's #GCancellable first, and
1091 	 * if it has been cancelled, then they will consider the task to have
1092 	 * returned an "Operation was cancelled" error
1093 	 * (%G_IO_ERROR_CANCELLED), regardless of any other error or return
1094 	 * value the task may have had.
1095 	 *
1096 	 * If @check_cancellable is %FALSE, then the #GTask will not check the
1097 	 * cancellable itself, and it is up to @task's owner to do this (eg,
1098 	 * via g_task_return_error_if_cancelled()).
1099 	 *
1100 	 * If you are using g_task_set_return_on_cancel() as well, then
1101 	 * you must leave check-cancellable set %TRUE.
1102 	 *
1103 	 * Params:
1104 	 *     checkCancellable = whether #GTask will check the state of
1105 	 *         its #GCancellable for you.
1106 	 *
1107 	 * Since: 2.36
1108 	 */
1109 	public void setCheckCancellable(bool checkCancellable)
1110 	{
1111 		g_task_set_check_cancellable(gTask, checkCancellable);
1112 	}
1113 
1114 	/**
1115 	 * Sets @task’s name, used in debugging and profiling. The name defaults to
1116 	 * %NULL.
1117 	 *
1118 	 * The task name should describe in a human readable way what the task does.
1119 	 * For example, ‘Open file’ or ‘Connect to network host’. It is used to set the
1120 	 * name of the #GSource used for idle completion of the task.
1121 	 *
1122 	 * This function may only be called before the @task is first used in a thread
1123 	 * other than the one it was constructed in.
1124 	 *
1125 	 * Params:
1126 	 *     name = a human readable name for the task, or %NULL to unset it
1127 	 *
1128 	 * Since: 2.60
1129 	 */
1130 	public void setName(string name)
1131 	{
1132 		g_task_set_name(gTask, Str.toStringz(name));
1133 	}
1134 
1135 	/**
1136 	 * Sets @task's priority. If you do not call this, it will default to
1137 	 * %G_PRIORITY_DEFAULT.
1138 	 *
1139 	 * This will affect the priority of #GSources created with
1140 	 * g_task_attach_source() and the scheduling of tasks run in threads,
1141 	 * and can also be explicitly retrieved later via
1142 	 * g_task_get_priority().
1143 	 *
1144 	 * Params:
1145 	 *     priority = the [priority][io-priority] of the request
1146 	 *
1147 	 * Since: 2.36
1148 	 */
1149 	public void setPriority(int priority)
1150 	{
1151 		g_task_set_priority(gTask, priority);
1152 	}
1153 
1154 	/**
1155 	 * Sets or clears @task's return-on-cancel flag. This is only
1156 	 * meaningful for tasks run via g_task_run_in_thread() or
1157 	 * g_task_run_in_thread_sync().
1158 	 *
1159 	 * If @return_on_cancel is %TRUE, then cancelling @task's
1160 	 * #GCancellable will immediately cause it to return, as though the
1161 	 * task's #GTaskThreadFunc had called
1162 	 * g_task_return_error_if_cancelled() and then returned.
1163 	 *
1164 	 * This allows you to create a cancellable wrapper around an
1165 	 * uninterruptable function. The #GTaskThreadFunc just needs to be
1166 	 * careful that it does not modify any externally-visible state after
1167 	 * it has been cancelled. To do that, the thread should call
1168 	 * g_task_set_return_on_cancel() again to (atomically) set
1169 	 * return-on-cancel %FALSE before making externally-visible changes;
1170 	 * if the task gets cancelled before the return-on-cancel flag could
1171 	 * be changed, g_task_set_return_on_cancel() will indicate this by
1172 	 * returning %FALSE.
1173 	 *
1174 	 * You can disable and re-enable this flag multiple times if you wish.
1175 	 * If the task's #GCancellable is cancelled while return-on-cancel is
1176 	 * %FALSE, then calling g_task_set_return_on_cancel() to set it %TRUE
1177 	 * again will cause the task to be cancelled at that point.
1178 	 *
1179 	 * If the task's #GCancellable is already cancelled before you call
1180 	 * g_task_run_in_thread()/g_task_run_in_thread_sync(), then the
1181 	 * #GTaskThreadFunc will still be run (for consistency), but the task
1182 	 * will also be completed right away.
1183 	 *
1184 	 * Params:
1185 	 *     returnOnCancel = whether the task returns automatically when
1186 	 *         it is cancelled.
1187 	 *
1188 	 * Returns: %TRUE if @task's return-on-cancel flag was changed to
1189 	 *     match @return_on_cancel. %FALSE if @task has already been
1190 	 *     cancelled.
1191 	 *
1192 	 * Since: 2.36
1193 	 */
1194 	public bool setReturnOnCancel(bool returnOnCancel)
1195 	{
1196 		return g_task_set_return_on_cancel(gTask, returnOnCancel) != 0;
1197 	}
1198 
1199 	/**
1200 	 * Sets @task's source tag. You can use this to tag a task return
1201 	 * value with a particular pointer (usually a pointer to the function
1202 	 * doing the tagging) and then later check it using
1203 	 * g_task_get_source_tag() (or g_async_result_is_tagged()) in the
1204 	 * task's "finish" function, to figure out if the response came from a
1205 	 * particular place.
1206 	 *
1207 	 * Params:
1208 	 *     sourceTag = an opaque pointer indicating the source of this task
1209 	 *
1210 	 * Since: 2.36
1211 	 */
1212 	public void setSourceTag(void* sourceTag)
1213 	{
1214 		g_task_set_source_tag(gTask, sourceTag);
1215 	}
1216 
1217 	/**
1218 	 * Sets @task's task data (freeing the existing task data, if any).
1219 	 *
1220 	 * Params:
1221 	 *     taskData = task-specific data
1222 	 *     taskDataDestroy = #GDestroyNotify for @task_data
1223 	 *
1224 	 * Since: 2.36
1225 	 */
1226 	public void setTaskData(void* taskData, GDestroyNotify taskDataDestroy)
1227 	{
1228 		g_task_set_task_data(gTask, taskData, taskDataDestroy);
1229 	}
1230 }