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 gstreamer.Pad;
26 
27 private import glib.ConstructionException;
28 private import glib.Str;
29 private import gobject.ObjectG;
30 private import gobject.Signals;
31 private import gstreamer.Buffer;
32 private import gstreamer.BufferList;
33 private import gstreamer.Caps;
34 private import gstreamer.Element;
35 private import gstreamer.Event;
36 private import gstreamer.Iterator;
37 private import gstreamer.ObjectGst;
38 private import gstreamer.PadTemplate;
39 private import gstreamer.Query;
40 private import gstreamer.StaticPadTemplate;
41 private import gstreamerc.gstreamer;
42 public  import gstreamerc.gstreamertypes;
43 public  import gtkc.gdktypes;
44 
45 
46 /**
47  * A #GstElement is linked to other elements via "pads", which are extremely
48  * light-weight generic link points.
49  * 
50  * Pads have a #GstPadDirection, source pads produce data, sink pads consume
51  * data.
52  * 
53  * Pads are typically created from a #GstPadTemplate with
54  * gst_pad_new_from_template() and are then added to a #GstElement. This usually
55  * happens when the element is created but it can also happen dynamically based
56  * on the data that the element is processing or based on the pads that the
57  * application requests.
58  * 
59  * Pads without pad templates can be created with gst_pad_new(),
60  * which takes a direction and a name as an argument.  If the name is %NULL,
61  * then a guaranteed unique name will be assigned to it.
62  * 
63  * A #GstElement creating a pad will typically use the various
64  * gst_pad_set_*_function() calls to register callbacks for events, queries or
65  * dataflow on the pads.
66  * 
67  * gst_pad_get_parent() will retrieve the #GstElement that owns the pad.
68  * 
69  * After two pads are retrieved from an element by gst_element_get_static_pad(),
70  * the pads can be linked with gst_pad_link(). (For quick links,
71  * you can also use gst_element_link(), which will make the obvious
72  * link for you if it's straightforward.). Pads can be unlinked again with
73  * gst_pad_unlink(). gst_pad_get_peer() can be used to check what the pad is
74  * linked to.
75  * 
76  * Before dataflow is possible on the pads, they need to be activated with
77  * gst_pad_set_active().
78  * 
79  * gst_pad_query() and gst_pad_peer_query() can be used to query various
80  * properties of the pad and the stream.
81  * 
82  * To send a #GstEvent on a pad, use gst_pad_send_event() and
83  * gst_pad_push_event(). Some events will be sticky on the pad, meaning that
84  * after they pass on the pad they can be queried later with
85  * gst_pad_get_sticky_event() and gst_pad_sticky_events_foreach().
86  * gst_pad_get_current_caps() and gst_pad_has_current_caps() are convenience
87  * functions to query the current sticky CAPS event on a pad.
88  * 
89  * GstElements will use gst_pad_push() and gst_pad_pull_range() to push out
90  * or pull in a buffer.
91  * 
92  * The dataflow, events and queries that happen on a pad can be monitored with
93  * probes that can be installed with gst_pad_add_probe(). gst_pad_is_blocked()
94  * can be used to check if a block probe is installed on the pad.
95  * gst_pad_is_blocking() checks if the blocking probe is currently blocking the
96  * pad. gst_pad_remove_probe() is used to remove a previously installed probe
97  * and unblock blocking probes if any.
98  * 
99  * Pad have an offset that can be retrieved with gst_pad_get_offset(). This
100  * offset will be applied to the running_time of all data passing over the pad.
101  * gst_pad_set_offset() can be used to change the offset.
102  * 
103  * Convenience functions exist to start, pause and stop the task on a pad with
104  * gst_pad_start_task(), gst_pad_pause_task() and gst_pad_stop_task()
105  * respectively.
106  */
107 public class Pad : ObjectGst
108 {
109 	/** the main Gtk struct */
110 	protected GstPad* gstPad;
111 
112 	/** Get the main Gtk struct */
113 	public GstPad* getPadStruct()
114 	{
115 		return gstPad;
116 	}
117 
118 	/** the main Gtk struct as a void* */
119 	protected override void* getStruct()
120 	{
121 		return cast(void*)gstPad;
122 	}
123 
124 	protected override void setStruct(GObject* obj)
125 	{
126 		gstPad = cast(GstPad*)obj;
127 		super.setStruct(obj);
128 	}
129 
130 	/**
131 	 * Sets our main struct and passes it to the parent class.
132 	 */
133 	public this (GstPad* gstPad, bool ownedRef = false)
134 	{
135 		this.gstPad = gstPad;
136 		super(cast(GstObject*)gstPad, ownedRef);
137 	}
138 
139 	/*
140 	 * Sets our main struct and passes it to the parent class.
141 	 * This one is additional to make gstreamer.Element addOnPadAdded()
142 	 * working without changes.
143 	 */
144 	public this (GObject* gstPad)
145 	{
146 		super(cast(GstObject*)gstPad);
147 		this.gstPad = cast(GstPad*) gstPad;
148 	}
149 	
150 	/**
151 	 * Queries a pad for the stream position.
152 	 * This is a convenience function for gstreamerD.
153 	 * Returns:
154 	 *  The current position in nanoseconds - GstFormat.TIME.
155 	 */
156 	public long queryPosition()
157 	{
158 		long cur_pos;
159 		queryPosition( GstFormat.TIME, cur_pos );
160 		return cur_pos;
161 	}
162 	
163 	/**
164 	 * Queries a pad for the stream duration.
165 	 * This is a convenience function for gstreamerD.
166 	 * Returns:
167 	 *  The duration in nanoseconds - GstFormat.TIME.
168 	 */
169 	public long queryDuration()
170 	{
171 		long cur_dur;
172 		queryDuration( GstFormat.TIME, cur_dur );
173 		return cur_dur;
174 	}
175 
176 	/**
177 	 */
178 
179 	/** */
180 	public static GType getType()
181 	{
182 		return gst_pad_get_type();
183 	}
184 
185 	/**
186 	 * Creates a new pad with the given name in the given direction.
187 	 * If name is %NULL, a guaranteed unique name (across all pads)
188 	 * will be assigned.
189 	 * This function makes a copy of the name so you can safely free the name.
190 	 *
191 	 * Params:
192 	 *     name = the name of the new pad.
193 	 *     direction = the #GstPadDirection of the pad.
194 	 *
195 	 * Return: a new #GstPad, or %NULL in
196 	 *     case of an error.
197 	 *
198 	 *     MT safe.
199 	 *
200 	 * Throws: ConstructionException GTK+ fails to create the object.
201 	 */
202 	public this(string name, GstPadDirection direction)
203 	{
204 		auto p = gst_pad_new(Str.toStringz(name), direction);
205 		
206 		if(p is null)
207 		{
208 			throw new ConstructionException("null returned by new");
209 		}
210 		
211 		this(cast(GstPad*) p);
212 	}
213 
214 	/**
215 	 * Creates a new pad with the given name from the given static template.
216 	 * If name is %NULL, a guaranteed unique name (across all pads)
217 	 * will be assigned.
218 	 * This function makes a copy of the name so you can safely free the name.
219 	 *
220 	 * Params:
221 	 *     templ = the #GstStaticPadTemplate to use
222 	 *     name = the name of the pad
223 	 *
224 	 * Return: a new #GstPad, or %NULL in
225 	 *     case of an error.
226 	 *
227 	 * Throws: ConstructionException GTK+ fails to create the object.
228 	 */
229 	public this(StaticPadTemplate templ, string name)
230 	{
231 		auto p = gst_pad_new_from_static_template((templ is null) ? null : templ.getStaticPadTemplateStruct(), Str.toStringz(name));
232 		
233 		if(p is null)
234 		{
235 			throw new ConstructionException("null returned by new_from_static_template");
236 		}
237 		
238 		this(cast(GstPad*) p);
239 	}
240 
241 	/**
242 	 * Creates a new pad with the given name from the given template.
243 	 * If name is %NULL, a guaranteed unique name (across all pads)
244 	 * will be assigned.
245 	 * This function makes a copy of the name so you can safely free the name.
246 	 *
247 	 * Params:
248 	 *     templ = the pad template to use
249 	 *     name = the name of the pad
250 	 *
251 	 * Return: a new #GstPad, or %NULL in
252 	 *     case of an error.
253 	 *
254 	 * Throws: ConstructionException GTK+ fails to create the object.
255 	 */
256 	public this(PadTemplate templ, string name)
257 	{
258 		auto p = gst_pad_new_from_template((templ is null) ? null : templ.getPadTemplateStruct(), Str.toStringz(name));
259 		
260 		if(p is null)
261 		{
262 			throw new ConstructionException("null returned by new_from_template");
263 		}
264 		
265 		this(cast(GstPad*) p);
266 	}
267 
268 	/**
269 	 * Gets a string representing the given pad-link return.
270 	 *
271 	 * Params:
272 	 *     ret = a #GstPadLinkReturn to get the name of.
273 	 *
274 	 * Return: a static string with the name of the pad-link return.
275 	 *
276 	 * Since: 1.4
277 	 */
278 	public static string linkGetName(GstPadLinkReturn ret)
279 	{
280 		return Str.toString(gst_pad_link_get_name(ret));
281 	}
282 
283 	/**
284 	 * Activates or deactivates the given pad in @mode via dispatching to the
285 	 * pad's activatemodefunc. For use from within pad activation functions only.
286 	 *
287 	 * If you don't know what this is, you probably don't want to call it.
288 	 *
289 	 * Params:
290 	 *     mode = the requested activation mode
291 	 *     active = whether or not the pad should be active.
292 	 *
293 	 * Return: %TRUE if the operation was successful.
294 	 *
295 	 *     MT safe.
296 	 */
297 	public bool activateMode(GstPadMode mode, bool active)
298 	{
299 		return gst_pad_activate_mode(gstPad, mode, active) != 0;
300 	}
301 
302 	/**
303 	 * Be notified of different states of pads. The provided callback is called for
304 	 * every state that matches @mask.
305 	 *
306 	 * Probes are called in groups: First GST_PAD_PROBE_TYPE_BLOCK probes are
307 	 * called, then others, then finally GST_PAD_PROBE_TYPE_IDLE. The only
308 	 * exception here are GST_PAD_PROBE_TYPE_IDLE probes that are called
309 	 * immediately if the pad is already idle while calling gst_pad_add_probe().
310 	 * In each of the groups, probes are called in the order in which they were
311 	 * added.
312 	 *
313 	 * Params:
314 	 *     mask = the probe mask
315 	 *     callback = #GstPadProbeCallback that will be called with notifications of
316 	 *         the pad state
317 	 *     userData = user data passed to the callback
318 	 *     destroyData = #GDestroyNotify for user_data
319 	 *
320 	 * Return: an id or 0 if no probe is pending. The id can be used to remove the
321 	 *     probe with gst_pad_remove_probe(). When using GST_PAD_PROBE_TYPE_IDLE it can
322 	 *     happen that the probe can be run immediately and if the probe returns
323 	 *     GST_PAD_PROBE_REMOVE this functions returns 0.
324 	 *
325 	 *     MT safe.
326 	 */
327 	public gulong addProbe(GstPadProbeType mask, GstPadProbeCallback callback, void* userData, GDestroyNotify destroyData)
328 	{
329 		return gst_pad_add_probe(gstPad, mask, callback, userData, destroyData);
330 	}
331 
332 	/**
333 	 * Checks if the source pad and the sink pad are compatible so they can be
334 	 * linked.
335 	 *
336 	 * Params:
337 	 *     sinkpad = the sink #GstPad.
338 	 *
339 	 * Return: %TRUE if the pads can be linked.
340 	 */
341 	public bool canLink(Pad sinkpad)
342 	{
343 		return gst_pad_can_link(gstPad, (sinkpad is null) ? null : sinkpad.getPadStruct()) != 0;
344 	}
345 
346 	/**
347 	 * Chain a buffer to @pad.
348 	 *
349 	 * The function returns #GST_FLOW_FLUSHING if the pad was flushing.
350 	 *
351 	 * If the buffer type is not acceptable for @pad (as negotiated with a
352 	 * preceding GST_EVENT_CAPS event), this function returns
353 	 * #GST_FLOW_NOT_NEGOTIATED.
354 	 *
355 	 * The function proceeds calling the chain function installed on @pad (see
356 	 * gst_pad_set_chain_function()) and the return value of that function is
357 	 * returned to the caller. #GST_FLOW_NOT_SUPPORTED is returned if @pad has no
358 	 * chain function.
359 	 *
360 	 * In all cases, success or failure, the caller loses its reference to @buffer
361 	 * after calling this function.
362 	 *
363 	 * Params:
364 	 *     buffer = the #GstBuffer to send, return GST_FLOW_ERROR
365 	 *         if not.
366 	 *
367 	 * Return: a #GstFlowReturn from the pad.
368 	 *
369 	 *     MT safe.
370 	 */
371 	public GstFlowReturn chain(Buffer buffer)
372 	{
373 		return gst_pad_chain(gstPad, (buffer is null) ? null : buffer.getBufferStruct());
374 	}
375 
376 	/**
377 	 * Chain a bufferlist to @pad.
378 	 *
379 	 * The function returns #GST_FLOW_FLUSHING if the pad was flushing.
380 	 *
381 	 * If @pad was not negotiated properly with a CAPS event, this function
382 	 * returns #GST_FLOW_NOT_NEGOTIATED.
383 	 *
384 	 * The function proceeds calling the chainlist function installed on @pad (see
385 	 * gst_pad_set_chain_list_function()) and the return value of that function is
386 	 * returned to the caller. #GST_FLOW_NOT_SUPPORTED is returned if @pad has no
387 	 * chainlist function.
388 	 *
389 	 * In all cases, success or failure, the caller loses its reference to @list
390 	 * after calling this function.
391 	 *
392 	 * MT safe.
393 	 *
394 	 * Params:
395 	 *     list = the #GstBufferList to send, return GST_FLOW_ERROR
396 	 *         if not.
397 	 *
398 	 * Return: a #GstFlowReturn from the pad.
399 	 */
400 	public GstFlowReturn chainList(BufferList list)
401 	{
402 		return gst_pad_chain_list(gstPad, (list is null) ? null : list.getBufferListStruct());
403 	}
404 
405 	/**
406 	 * Check and clear the #GST_PAD_FLAG_NEED_RECONFIGURE flag on @pad and return %TRUE
407 	 * if the flag was set.
408 	 *
409 	 * Return: %TRUE is the GST_PAD_FLAG_NEED_RECONFIGURE flag was set on @pad.
410 	 */
411 	public bool checkReconfigure()
412 	{
413 		return gst_pad_check_reconfigure(gstPad) != 0;
414 	}
415 
416 	/**
417 	 * Creates a stream-id for the source #GstPad @pad by combining the
418 	 * upstream information with the optional @stream_id of the stream
419 	 * of @pad. @pad must have a parent #GstElement and which must have zero
420 	 * or one sinkpad. @stream_id can only be %NULL if the parent element
421 	 * of @pad has only a single source pad.
422 	 *
423 	 * This function generates an unique stream-id by getting the upstream
424 	 * stream-start event stream ID and appending @stream_id to it. If the
425 	 * element has no sinkpad it will generate an upstream stream-id by
426 	 * doing an URI query on the element and in the worst case just uses
427 	 * a random number. Source elements that don't implement the URI
428 	 * handler interface should ideally generate a unique, deterministic
429 	 * stream-id manually instead.
430 	 *
431 	 * Since stream IDs are sorted alphabetically, any numbers in the
432 	 * stream ID should be printed with a fixed number of characters,
433 	 * preceded by 0's, such as by using the format \%03u instead of \%u.
434 	 *
435 	 * Params:
436 	 *     parent = Parent #GstElement of @pad
437 	 *     streamId = The stream-id
438 	 *
439 	 * Return: A stream-id for @pad. g_free() after usage.
440 	 */
441 	public string createStreamId(Element parent, string streamId)
442 	{
443 		auto retStr = gst_pad_create_stream_id(gstPad, (parent is null) ? null : parent.getElementStruct(), Str.toStringz(streamId));
444 		
445 		scope(exit) Str.freeString(retStr);
446 		return Str.toString(retStr);
447 	}
448 
449 	/**
450 	 * Creates a stream-id for the source #GstPad @pad by combining the
451 	 * upstream information with the optional @stream_id of the stream
452 	 * of @pad. @pad must have a parent #GstElement and which must have zero
453 	 * or one sinkpad. @stream_id can only be %NULL if the parent element
454 	 * of @pad has only a single source pad.
455 	 *
456 	 * This function generates an unique stream-id by getting the upstream
457 	 * stream-start event stream ID and appending @stream_id to it. If the
458 	 * element has no sinkpad it will generate an upstream stream-id by
459 	 * doing an URI query on the element and in the worst case just uses
460 	 * a random number. Source elements that don't implement the URI
461 	 * handler interface should ideally generate a unique, deterministic
462 	 * stream-id manually instead.
463 	 *
464 	 * Params:
465 	 *     parent = Parent #GstElement of @pad
466 	 *     streamId = The stream-id
467 	 *     varArgs = parameters for the @stream_id format string
468 	 *
469 	 * Return: A stream-id for @pad. g_free() after usage.
470 	 */
471 	public string createStreamIdPrintfValist(Element parent, string streamId, void* varArgs)
472 	{
473 		auto retStr = gst_pad_create_stream_id_printf_valist(gstPad, (parent is null) ? null : parent.getElementStruct(), Str.toStringz(streamId), varArgs);
474 		
475 		scope(exit) Str.freeString(retStr);
476 		return Str.toString(retStr);
477 	}
478 
479 	/**
480 	 * Invokes the default event handler for the given pad.
481 	 *
482 	 * The EOS event will pause the task associated with @pad before it is forwarded
483 	 * to all internally linked pads,
484 	 *
485 	 * The event is sent to all pads internally linked to @pad. This function
486 	 * takes ownership of @event.
487 	 *
488 	 * Params:
489 	 *     parent = the parent of @pad or %NULL
490 	 *     event = the #GstEvent to handle.
491 	 *
492 	 * Return: %TRUE if the event was sent successfully.
493 	 */
494 	public bool eventDefault(ObjectGst parent, Event event)
495 	{
496 		return gst_pad_event_default(gstPad, (parent is null) ? null : parent.getObjectGstStruct(), (event is null) ? null : event.getEventStruct()) != 0;
497 	}
498 
499 	/**
500 	 * Calls @forward for all internally linked pads of @pad. This function deals with
501 	 * dynamically changing internal pads and will make sure that the @forward
502 	 * function is only called once for each pad.
503 	 *
504 	 * When @forward returns %TRUE, no further pads will be processed.
505 	 *
506 	 * Params:
507 	 *     forward = a #GstPadForwardFunction
508 	 *     userData = user data passed to @forward
509 	 *
510 	 * Return: %TRUE if one of the dispatcher functions returned %TRUE.
511 	 */
512 	public bool forward(GstPadForwardFunction forward, void* userData)
513 	{
514 		return gst_pad_forward(gstPad, forward, userData) != 0;
515 	}
516 
517 	/**
518 	 * Gets the capabilities of the allowed media types that can flow through
519 	 * @pad and its peer.
520 	 *
521 	 * The allowed capabilities is calculated as the intersection of the results of
522 	 * calling gst_pad_query_caps() on @pad and its peer. The caller owns a reference
523 	 * on the resulting caps.
524 	 *
525 	 * Return: the allowed #GstCaps of the
526 	 *     pad link. Unref the caps when you no longer need it. This
527 	 *     function returns %NULL when @pad has no peer.
528 	 *
529 	 *     MT safe.
530 	 */
531 	public Caps getAllowedCaps()
532 	{
533 		auto p = gst_pad_get_allowed_caps(gstPad);
534 		
535 		if(p is null)
536 		{
537 			return null;
538 		}
539 		
540 		return ObjectG.getDObject!(Caps)(cast(GstCaps*) p, true);
541 	}
542 
543 	/**
544 	 * Gets the capabilities currently configured on @pad with the last
545 	 * #GST_EVENT_CAPS event.
546 	 *
547 	 * Return: the current caps of the pad with incremented ref-count.
548 	 */
549 	public Caps getCurrentCaps()
550 	{
551 		auto p = gst_pad_get_current_caps(gstPad);
552 		
553 		if(p is null)
554 		{
555 			return null;
556 		}
557 		
558 		return ObjectG.getDObject!(Caps)(cast(GstCaps*) p, true);
559 	}
560 
561 	/**
562 	 * Gets the direction of the pad. The direction of the pad is
563 	 * decided at construction time so this function does not take
564 	 * the LOCK.
565 	 *
566 	 * Return: the #GstPadDirection of the pad.
567 	 *
568 	 *     MT safe.
569 	 */
570 	public GstPadDirection getDirection()
571 	{
572 		return gst_pad_get_direction(gstPad);
573 	}
574 
575 	/**
576 	 * Gets the private data of a pad.
577 	 * No locking is performed in this function.
578 	 *
579 	 * Return: a #gpointer to the private data.
580 	 */
581 	public void* getElementPrivate()
582 	{
583 		return gst_pad_get_element_private(gstPad);
584 	}
585 
586 	/**
587 	 * Gets the #GstFlowReturn return from the last data passed by this pad.
588 	 *
589 	 * Since: 1.4
590 	 */
591 	public GstFlowReturn getLastFlowReturn()
592 	{
593 		return gst_pad_get_last_flow_return(gstPad);
594 	}
595 
596 	/**
597 	 * Get the offset applied to the running time of @pad. @pad has to be a source
598 	 * pad.
599 	 *
600 	 * Return: the offset.
601 	 */
602 	public long getOffset()
603 	{
604 		return gst_pad_get_offset(gstPad);
605 	}
606 
607 	/**
608 	 * Gets the template for @pad.
609 	 *
610 	 * Return: the #GstPadTemplate from which
611 	 *     this pad was instantiated, or %NULL if this pad has no
612 	 *     template. Unref after usage.
613 	 */
614 	public PadTemplate getPadTemplate()
615 	{
616 		auto p = gst_pad_get_pad_template(gstPad);
617 		
618 		if(p is null)
619 		{
620 			return null;
621 		}
622 		
623 		return ObjectG.getDObject!(PadTemplate)(cast(GstPadTemplate*) p, true);
624 	}
625 
626 	/**
627 	 * Gets the capabilities for @pad's template.
628 	 *
629 	 * Return: the #GstCaps of this pad template.
630 	 *     Unref after usage.
631 	 */
632 	public Caps getPadTemplateCaps()
633 	{
634 		auto p = gst_pad_get_pad_template_caps(gstPad);
635 		
636 		if(p is null)
637 		{
638 			return null;
639 		}
640 		
641 		return ObjectG.getDObject!(Caps)(cast(GstCaps*) p, true);
642 	}
643 
644 	/**
645 	 * Gets the parent of @pad, cast to a #GstElement. If a @pad has no parent or
646 	 * its parent is not an element, return %NULL.
647 	 *
648 	 * Return: the parent of the pad. The
649 	 *     caller has a reference on the parent, so unref when you're finished
650 	 *     with it.
651 	 *
652 	 *     MT safe.
653 	 */
654 	public Element getParentElement()
655 	{
656 		auto p = gst_pad_get_parent_element(gstPad);
657 		
658 		if(p is null)
659 		{
660 			return null;
661 		}
662 		
663 		return ObjectG.getDObject!(Element)(cast(GstElement*) p, true);
664 	}
665 
666 	/**
667 	 * Gets the peer of @pad. This function refs the peer pad so
668 	 * you need to unref it after use.
669 	 *
670 	 * Return: the peer #GstPad. Unref after usage.
671 	 *
672 	 *     MT safe.
673 	 */
674 	public Pad getPeer()
675 	{
676 		auto p = gst_pad_get_peer(gstPad);
677 		
678 		if(p is null)
679 		{
680 			return null;
681 		}
682 		
683 		return ObjectG.getDObject!(Pad)(cast(GstPad*) p, true);
684 	}
685 
686 	/**
687 	 * When @pad is flushing this function returns #GST_FLOW_FLUSHING
688 	 * immediately and @buffer is %NULL.
689 	 *
690 	 * Calls the getrange function of @pad, see #GstPadGetRangeFunction for a
691 	 * description of a getrange function. If @pad has no getrange function
692 	 * installed (see gst_pad_set_getrange_function()) this function returns
693 	 * #GST_FLOW_NOT_SUPPORTED.
694 	 *
695 	 * If @buffer points to a variable holding %NULL, a valid new #GstBuffer will be
696 	 * placed in @buffer when this function returns #GST_FLOW_OK. The new buffer
697 	 * must be freed with gst_buffer_unref() after usage.
698 	 *
699 	 * When @buffer points to a variable that points to a valid #GstBuffer, the
700 	 * buffer will be filled with the result data when this function returns
701 	 * #GST_FLOW_OK. If the provided buffer is larger than @size, only
702 	 * @size bytes will be filled in the result buffer and its size will be updated
703 	 * accordingly.
704 	 *
705 	 * Note that less than @size bytes can be returned in @buffer when, for example,
706 	 * an EOS condition is near or when @buffer is not large enough to hold @size
707 	 * bytes. The caller should check the result buffer size to get the result size.
708 	 *
709 	 * When this function returns any other result value than #GST_FLOW_OK, @buffer
710 	 * will be unchanged.
711 	 *
712 	 * This is a lowlevel function. Usually gst_pad_pull_range() is used.
713 	 *
714 	 * Params:
715 	 *     offset = The start offset of the buffer
716 	 *     size = The length of the buffer
717 	 *     buffer = a pointer to hold the #GstBuffer,
718 	 *         returns #GST_FLOW_ERROR if %NULL.
719 	 *
720 	 * Return: a #GstFlowReturn from the pad.
721 	 *
722 	 *     MT safe.
723 	 */
724 	public GstFlowReturn getRange(ulong offset, uint size, out Buffer buffer)
725 	{
726 		GstBuffer* outbuffer = null;
727 		
728 		auto p = gst_pad_get_range(gstPad, offset, size, &outbuffer);
729 		
730 		buffer = ObjectG.getDObject!(Buffer)(outbuffer);
731 		
732 		return p;
733 	}
734 
735 	/**
736 	 * Returns a new reference of the sticky event of type @event_type
737 	 * from the event.
738 	 *
739 	 * Params:
740 	 *     eventType = the #GstEventType that should be retrieved.
741 	 *     idx = the index of the event
742 	 *
743 	 * Return: a #GstEvent of type
744 	 *     @event_type or %NULL when no event of @event_type was on
745 	 *     @pad. Unref after usage.
746 	 */
747 	public Event getStickyEvent(GstEventType eventType, uint idx)
748 	{
749 		auto p = gst_pad_get_sticky_event(gstPad, eventType, idx);
750 		
751 		if(p is null)
752 		{
753 			return null;
754 		}
755 		
756 		return ObjectG.getDObject!(Event)(cast(GstEvent*) p, true);
757 	}
758 
759 	/**
760 	 * Returns the current stream-id for the @pad, or %NULL if none has been
761 	 * set yet, i.e. the pad has not received a stream-start event yet.
762 	 *
763 	 * This is a convenience wrapper around gst_pad_get_sticky_event() and
764 	 * gst_event_parse_stream_start().
765 	 *
766 	 * The returned stream-id string should be treated as an opaque string, its
767 	 * contents should not be interpreted.
768 	 *
769 	 * Return: a newly-allocated copy of the stream-id for
770 	 *     @pad, or %NULL.  g_free() the returned string when no longer
771 	 *     needed.
772 	 *
773 	 * Since: 1.2
774 	 */
775 	public string getStreamId()
776 	{
777 		auto retStr = gst_pad_get_stream_id(gstPad);
778 		
779 		scope(exit) Str.freeString(retStr);
780 		return Str.toString(retStr);
781 	}
782 
783 	/**
784 	 * Check if @pad has caps set on it with a #GST_EVENT_CAPS event.
785 	 *
786 	 * Return: %TRUE when @pad has caps associated with it.
787 	 */
788 	public bool hasCurrentCaps()
789 	{
790 		return gst_pad_has_current_caps(gstPad) != 0;
791 	}
792 
793 	/**
794 	 * Query if a pad is active
795 	 *
796 	 * Return: %TRUE if the pad is active.
797 	 *
798 	 *     MT safe.
799 	 */
800 	public bool isActive()
801 	{
802 		return gst_pad_is_active(gstPad) != 0;
803 	}
804 
805 	/**
806 	 * Checks if the pad is blocked or not. This function returns the
807 	 * last requested state of the pad. It is not certain that the pad
808 	 * is actually blocking at this point (see gst_pad_is_blocking()).
809 	 *
810 	 * Return: %TRUE if the pad is blocked.
811 	 *
812 	 *     MT safe.
813 	 */
814 	public bool isBlocked()
815 	{
816 		return gst_pad_is_blocked(gstPad) != 0;
817 	}
818 
819 	/**
820 	 * Checks if the pad is blocking or not. This is a guaranteed state
821 	 * of whether the pad is actually blocking on a #GstBuffer or a #GstEvent.
822 	 *
823 	 * Return: %TRUE if the pad is blocking.
824 	 *
825 	 *     MT safe.
826 	 */
827 	public bool isBlocking()
828 	{
829 		return gst_pad_is_blocking(gstPad) != 0;
830 	}
831 
832 	/**
833 	 * Checks if a @pad is linked to another pad or not.
834 	 *
835 	 * Return: %TRUE if the pad is linked, %FALSE otherwise.
836 	 *
837 	 *     MT safe.
838 	 */
839 	public bool isLinked()
840 	{
841 		return gst_pad_is_linked(gstPad) != 0;
842 	}
843 
844 	/**
845 	 * Gets an iterator for the pads to which the given pad is linked to inside
846 	 * of the parent element.
847 	 *
848 	 * Each #GstPad element yielded by the iterator will have its refcount increased,
849 	 * so unref after use.
850 	 *
851 	 * Free-function: gst_iterator_free
852 	 *
853 	 * Return: a new #GstIterator of #GstPad
854 	 *     or %NULL when the pad does not have an iterator function
855 	 *     configured. Use gst_iterator_free() after usage.
856 	 */
857 	public Iterator iterateInternalLinks()
858 	{
859 		auto p = gst_pad_iterate_internal_links(gstPad);
860 		
861 		if(p is null)
862 		{
863 			return null;
864 		}
865 		
866 		return ObjectG.getDObject!(Iterator)(cast(GstIterator*) p, true);
867 	}
868 
869 	/**
870 	 * Iterate the list of pads to which the given pad is linked to inside of
871 	 * the parent element.
872 	 * This is the default handler, and thus returns an iterator of all of the
873 	 * pads inside the parent element with opposite direction.
874 	 *
875 	 * The caller must free this iterator after use with gst_iterator_free().
876 	 *
877 	 * Params:
878 	 *     parent = the parent of @pad or %NULL
879 	 *
880 	 * Return: a #GstIterator of #GstPad, or %NULL if @pad
881 	 *     has no parent. Unref each returned pad with gst_object_unref().
882 	 */
883 	public Iterator iterateInternalLinksDefault(ObjectGst parent)
884 	{
885 		auto p = gst_pad_iterate_internal_links_default(gstPad, (parent is null) ? null : parent.getObjectGstStruct());
886 		
887 		if(p is null)
888 		{
889 			return null;
890 		}
891 		
892 		return ObjectG.getDObject!(Iterator)(cast(GstIterator*) p, true);
893 	}
894 
895 	/**
896 	 * Links the source pad and the sink pad.
897 	 *
898 	 * Params:
899 	 *     sinkpad = the sink #GstPad to link.
900 	 *
901 	 * Return: A result code indicating if the connection worked or
902 	 *     what went wrong.
903 	 *
904 	 *     MT Safe.
905 	 */
906 	public GstPadLinkReturn link(Pad sinkpad)
907 	{
908 		return gst_pad_link(gstPad, (sinkpad is null) ? null : sinkpad.getPadStruct());
909 	}
910 
911 	/**
912 	 * Links the source pad and the sink pad.
913 	 *
914 	 * This variant of #gst_pad_link provides a more granular control on the
915 	 * checks being done when linking. While providing some considerable speedups
916 	 * the caller of this method must be aware that wrong usage of those flags
917 	 * can cause severe issues. Refer to the documentation of #GstPadLinkCheck
918 	 * for more information.
919 	 *
920 	 * MT Safe.
921 	 *
922 	 * Params:
923 	 *     sinkpad = the sink #GstPad to link.
924 	 *     flags = the checks to validate when linking
925 	 *
926 	 * Return: A result code indicating if the connection worked or
927 	 *     what went wrong.
928 	 */
929 	public GstPadLinkReturn linkFull(Pad sinkpad, GstPadLinkCheck flags)
930 	{
931 		return gst_pad_link_full(gstPad, (sinkpad is null) ? null : sinkpad.getPadStruct(), flags);
932 	}
933 
934 	/**
935 	 * Mark a pad for needing reconfiguration. The next call to
936 	 * gst_pad_check_reconfigure() will return %TRUE after this call.
937 	 */
938 	public void markReconfigure()
939 	{
940 		gst_pad_mark_reconfigure(gstPad);
941 	}
942 
943 	/**
944 	 * Check the #GST_PAD_FLAG_NEED_RECONFIGURE flag on @pad and return %TRUE
945 	 * if the flag was set.
946 	 *
947 	 * Return: %TRUE is the GST_PAD_FLAG_NEED_RECONFIGURE flag is set on @pad.
948 	 */
949 	public bool needsReconfigure()
950 	{
951 		return gst_pad_needs_reconfigure(gstPad) != 0;
952 	}
953 
954 	/**
955 	 * Pause the task of @pad. This function will also wait until the
956 	 * function executed by the task is finished if this function is not
957 	 * called from the task function.
958 	 *
959 	 * Return: a %TRUE if the task could be paused or %FALSE when the pad
960 	 *     has no task.
961 	 */
962 	public bool pauseTask()
963 	{
964 		return gst_pad_pause_task(gstPad) != 0;
965 	}
966 
967 	/**
968 	 * Performs gst_pad_query() on the peer of @pad.
969 	 *
970 	 * The caller is responsible for both the allocation and deallocation of
971 	 * the query structure.
972 	 *
973 	 * Params:
974 	 *     query = the #GstQuery to perform.
975 	 *
976 	 * Return: %TRUE if the query could be performed. This function returns %FALSE
977 	 *     if @pad has no peer.
978 	 */
979 	public bool peerQuery(Query query)
980 	{
981 		return gst_pad_peer_query(gstPad, (query is null) ? null : query.getQueryStruct()) != 0;
982 	}
983 
984 	/**
985 	 * Check if the peer of @pad accepts @caps. If @pad has no peer, this function
986 	 * returns %TRUE.
987 	 *
988 	 * Params:
989 	 *     caps = a #GstCaps to check on the pad
990 	 *
991 	 * Return: %TRUE if the peer of @pad can accept the caps or @pad has no peer.
992 	 */
993 	public bool peerQueryAcceptCaps(Caps caps)
994 	{
995 		return gst_pad_peer_query_accept_caps(gstPad, (caps is null) ? null : caps.getCapsStruct()) != 0;
996 	}
997 
998 	/**
999 	 * Gets the capabilities of the peer connected to this pad. Similar to
1000 	 * gst_pad_query_caps().
1001 	 *
1002 	 * When called on srcpads @filter contains the caps that
1003 	 * upstream could produce in the order preferred by upstream. When
1004 	 * called on sinkpads @filter contains the caps accepted by
1005 	 * downstream in the preferred order. @filter might be %NULL but
1006 	 * if it is not %NULL the returned caps will be a subset of @filter.
1007 	 *
1008 	 * Params:
1009 	 *     filter = a #GstCaps filter, or %NULL.
1010 	 *
1011 	 * Return: the caps of the peer pad with incremented ref-count. When there is
1012 	 *     no peer pad, this function returns @filter or, when @filter is %NULL, ANY
1013 	 *     caps.
1014 	 */
1015 	public Caps peerQueryCaps(Caps filter)
1016 	{
1017 		auto p = gst_pad_peer_query_caps(gstPad, (filter is null) ? null : filter.getCapsStruct());
1018 		
1019 		if(p is null)
1020 		{
1021 			return null;
1022 		}
1023 		
1024 		return ObjectG.getDObject!(Caps)(cast(GstCaps*) p, true);
1025 	}
1026 
1027 	/**
1028 	 * Queries the peer pad of a given sink pad to convert @src_val in @src_format
1029 	 * to @dest_format.
1030 	 *
1031 	 * Params:
1032 	 *     srcFormat = a #GstFormat to convert from.
1033 	 *     srcVal = a value to convert.
1034 	 *     destFormat = the #GstFormat to convert to.
1035 	 *     destVal = a pointer to the result.
1036 	 *
1037 	 * Return: %TRUE if the query could be performed.
1038 	 */
1039 	public bool peerQueryConvert(GstFormat srcFormat, long srcVal, GstFormat destFormat, out long destVal)
1040 	{
1041 		return gst_pad_peer_query_convert(gstPad, srcFormat, srcVal, destFormat, &destVal) != 0;
1042 	}
1043 
1044 	/**
1045 	 * Queries the peer pad of a given sink pad for the total stream duration.
1046 	 *
1047 	 * Params:
1048 	 *     format = the #GstFormat requested
1049 	 *     duration = a location in which to store the total
1050 	 *         duration, or %NULL.
1051 	 *
1052 	 * Return: %TRUE if the query could be performed.
1053 	 */
1054 	public bool peerQueryDuration(GstFormat format, out long duration)
1055 	{
1056 		return gst_pad_peer_query_duration(gstPad, format, &duration) != 0;
1057 	}
1058 
1059 	/**
1060 	 * Queries the peer of a given sink pad for the stream position.
1061 	 *
1062 	 * Params:
1063 	 *     format = the #GstFormat requested
1064 	 *     cur = a location in which to store the current
1065 	 *         position, or %NULL.
1066 	 *
1067 	 * Return: %TRUE if the query could be performed.
1068 	 */
1069 	public bool peerQueryPosition(GstFormat format, out long cur)
1070 	{
1071 		return gst_pad_peer_query_position(gstPad, format, &cur) != 0;
1072 	}
1073 
1074 	/**
1075 	 * Checks if all internally linked pads of @pad accepts the caps in @query and
1076 	 * returns the intersection of the results.
1077 	 *
1078 	 * This function is useful as a default accept caps query function for an element
1079 	 * that can handle any stream format, but requires caps that are acceptable for
1080 	 * all opposite pads.
1081 	 *
1082 	 * Params:
1083 	 *     query = an ACCEPT_CAPS #GstQuery.
1084 	 *
1085 	 * Return: %TRUE if @query could be executed
1086 	 */
1087 	public bool proxyQueryAcceptCaps(Query query)
1088 	{
1089 		return gst_pad_proxy_query_accept_caps(gstPad, (query is null) ? null : query.getQueryStruct()) != 0;
1090 	}
1091 
1092 	/**
1093 	 * Calls gst_pad_query_caps() for all internally linked pads of @pad and returns
1094 	 * the intersection of the results.
1095 	 *
1096 	 * This function is useful as a default caps query function for an element
1097 	 * that can handle any stream format, but requires all its pads to have
1098 	 * the same caps.  Two such elements are tee and adder.
1099 	 *
1100 	 * Params:
1101 	 *     query = a CAPS #GstQuery.
1102 	 *
1103 	 * Return: %TRUE if @query could be executed
1104 	 */
1105 	public bool proxyQueryCaps(Query query)
1106 	{
1107 		return gst_pad_proxy_query_caps(gstPad, (query is null) ? null : query.getQueryStruct()) != 0;
1108 	}
1109 
1110 	/**
1111 	 * Pulls a @buffer from the peer pad or fills up a provided buffer.
1112 	 *
1113 	 * This function will first trigger the pad block signal if it was
1114 	 * installed.
1115 	 *
1116 	 * When @pad is not linked #GST_FLOW_NOT_LINKED is returned else this
1117 	 * function returns the result of gst_pad_get_range() on the peer pad.
1118 	 * See gst_pad_get_range() for a list of return values and for the
1119 	 * semantics of the arguments of this function.
1120 	 *
1121 	 * If @buffer points to a variable holding %NULL, a valid new #GstBuffer will be
1122 	 * placed in @buffer when this function returns #GST_FLOW_OK. The new buffer
1123 	 * must be freed with gst_buffer_unref() after usage. When this function
1124 	 * returns any other result value, @buffer will still point to %NULL.
1125 	 *
1126 	 * When @buffer points to a variable that points to a valid #GstBuffer, the
1127 	 * buffer will be filled with the result data when this function returns
1128 	 * #GST_FLOW_OK. When this function returns any other result value,
1129 	 * @buffer will be unchanged. If the provided buffer is larger than @size, only
1130 	 * @size bytes will be filled in the result buffer and its size will be updated
1131 	 * accordingly.
1132 	 *
1133 	 * Note that less than @size bytes can be returned in @buffer when, for example,
1134 	 * an EOS condition is near or when @buffer is not large enough to hold @size
1135 	 * bytes. The caller should check the result buffer size to get the result size.
1136 	 *
1137 	 * Params:
1138 	 *     offset = The start offset of the buffer
1139 	 *     size = The length of the buffer
1140 	 *     buffer = a pointer to hold the #GstBuffer, returns
1141 	 *         GST_FLOW_ERROR if %NULL.
1142 	 *
1143 	 * Return: a #GstFlowReturn from the peer pad.
1144 	 *
1145 	 *     MT safe.
1146 	 */
1147 	public GstFlowReturn pullRange(ulong offset, uint size, out Buffer buffer)
1148 	{
1149 		GstBuffer* outbuffer = null;
1150 		
1151 		auto p = gst_pad_pull_range(gstPad, offset, size, &outbuffer);
1152 		
1153 		buffer = ObjectG.getDObject!(Buffer)(outbuffer);
1154 		
1155 		return p;
1156 	}
1157 
1158 	/**
1159 	 * Pushes a buffer to the peer of @pad.
1160 	 *
1161 	 * This function will call installed block probes before triggering any
1162 	 * installed data probes.
1163 	 *
1164 	 * The function proceeds calling gst_pad_chain() on the peer pad and returns
1165 	 * the value from that function. If @pad has no peer, #GST_FLOW_NOT_LINKED will
1166 	 * be returned.
1167 	 *
1168 	 * In all cases, success or failure, the caller loses its reference to @buffer
1169 	 * after calling this function.
1170 	 *
1171 	 * Params:
1172 	 *     buffer = the #GstBuffer to push returns GST_FLOW_ERROR
1173 	 *         if not.
1174 	 *
1175 	 * Return: a #GstFlowReturn from the peer pad.
1176 	 *
1177 	 *     MT safe.
1178 	 */
1179 	public GstFlowReturn push(Buffer buffer)
1180 	{
1181 		return gst_pad_push(gstPad, (buffer is null) ? null : buffer.getBufferStruct());
1182 	}
1183 
1184 	/**
1185 	 * Sends the event to the peer of the given pad. This function is
1186 	 * mainly used by elements to send events to their peer
1187 	 * elements.
1188 	 *
1189 	 * This function takes ownership of the provided event so you should
1190 	 * gst_event_ref() it if you want to reuse the event after this call.
1191 	 *
1192 	 * Params:
1193 	 *     event = the #GstEvent to send to the pad.
1194 	 *
1195 	 * Return: %TRUE if the event was handled.
1196 	 *
1197 	 *     MT safe.
1198 	 */
1199 	public bool pushEvent(Event event)
1200 	{
1201 		return gst_pad_push_event(gstPad, (event is null) ? null : event.getEventStruct()) != 0;
1202 	}
1203 
1204 	/**
1205 	 * Pushes a buffer list to the peer of @pad.
1206 	 *
1207 	 * This function will call installed block probes before triggering any
1208 	 * installed data probes.
1209 	 *
1210 	 * The function proceeds calling the chain function on the peer pad and returns
1211 	 * the value from that function. If @pad has no peer, #GST_FLOW_NOT_LINKED will
1212 	 * be returned. If the peer pad does not have any installed chainlist function
1213 	 * every group buffer of the list will be merged into a normal #GstBuffer and
1214 	 * chained via gst_pad_chain().
1215 	 *
1216 	 * In all cases, success or failure, the caller loses its reference to @list
1217 	 * after calling this function.
1218 	 *
1219 	 * Params:
1220 	 *     list = the #GstBufferList to push returns GST_FLOW_ERROR
1221 	 *         if not.
1222 	 *
1223 	 * Return: a #GstFlowReturn from the peer pad.
1224 	 *
1225 	 *     MT safe.
1226 	 */
1227 	public GstFlowReturn pushList(BufferList list)
1228 	{
1229 		return gst_pad_push_list(gstPad, (list is null) ? null : list.getBufferListStruct());
1230 	}
1231 
1232 	/**
1233 	 * Dispatches a query to a pad. The query should have been allocated by the
1234 	 * caller via one of the type-specific allocation functions. The element that
1235 	 * the pad belongs to is responsible for filling the query with an appropriate
1236 	 * response, which should then be parsed with a type-specific query parsing
1237 	 * function.
1238 	 *
1239 	 * Again, the caller is responsible for both the allocation and deallocation of
1240 	 * the query structure.
1241 	 *
1242 	 * Please also note that some queries might need a running pipeline to work.
1243 	 *
1244 	 * Params:
1245 	 *     query = the #GstQuery to perform.
1246 	 *
1247 	 * Return: %TRUE if the query could be performed.
1248 	 */
1249 	public bool query(Query query)
1250 	{
1251 		return gst_pad_query(gstPad, (query is null) ? null : query.getQueryStruct()) != 0;
1252 	}
1253 
1254 	/**
1255 	 * Check if the given pad accepts the caps.
1256 	 *
1257 	 * Params:
1258 	 *     caps = a #GstCaps to check on the pad
1259 	 *
1260 	 * Return: %TRUE if the pad can accept the caps.
1261 	 */
1262 	public bool queryAcceptCaps(Caps caps)
1263 	{
1264 		return gst_pad_query_accept_caps(gstPad, (caps is null) ? null : caps.getCapsStruct()) != 0;
1265 	}
1266 
1267 	/**
1268 	 * Gets the capabilities this pad can produce or consume.
1269 	 * Note that this method doesn't necessarily return the caps set by sending a
1270 	 * gst_event_new_caps() - use gst_pad_get_current_caps() for that instead.
1271 	 * gst_pad_query_caps returns all possible caps a pad can operate with, using
1272 	 * the pad's CAPS query function, If the query fails, this function will return
1273 	 * @filter, if not %NULL, otherwise ANY.
1274 	 *
1275 	 * When called on sinkpads @filter contains the caps that
1276 	 * upstream could produce in the order preferred by upstream. When
1277 	 * called on srcpads @filter contains the caps accepted by
1278 	 * downstream in the preferred order. @filter might be %NULL but
1279 	 * if it is not %NULL the returned caps will be a subset of @filter.
1280 	 *
1281 	 * Note that this function does not return writable #GstCaps, use
1282 	 * gst_caps_make_writable() before modifying the caps.
1283 	 *
1284 	 * Params:
1285 	 *     filter = suggested #GstCaps, or %NULL
1286 	 *
1287 	 * Return: the caps of the pad with incremented ref-count.
1288 	 */
1289 	public Caps queryCaps(Caps filter)
1290 	{
1291 		auto p = gst_pad_query_caps(gstPad, (filter is null) ? null : filter.getCapsStruct());
1292 		
1293 		if(p is null)
1294 		{
1295 			return null;
1296 		}
1297 		
1298 		return ObjectG.getDObject!(Caps)(cast(GstCaps*) p, true);
1299 	}
1300 
1301 	/**
1302 	 * Queries a pad to convert @src_val in @src_format to @dest_format.
1303 	 *
1304 	 * Params:
1305 	 *     srcFormat = a #GstFormat to convert from.
1306 	 *     srcVal = a value to convert.
1307 	 *     destFormat = the #GstFormat to convert to.
1308 	 *     destVal = a pointer to the result.
1309 	 *
1310 	 * Return: %TRUE if the query could be performed.
1311 	 */
1312 	public bool queryConvert(GstFormat srcFormat, long srcVal, GstFormat destFormat, out long destVal)
1313 	{
1314 		return gst_pad_query_convert(gstPad, srcFormat, srcVal, destFormat, &destVal) != 0;
1315 	}
1316 
1317 	/**
1318 	 * Invokes the default query handler for the given pad.
1319 	 * The query is sent to all pads internally linked to @pad. Note that
1320 	 * if there are many possible sink pads that are internally linked to
1321 	 * @pad, only one will be sent the query.
1322 	 * Multi-sinkpad elements should implement custom query handlers.
1323 	 *
1324 	 * Params:
1325 	 *     parent = the parent of @pad or %NULL
1326 	 *     query = the #GstQuery to handle.
1327 	 *
1328 	 * Return: %TRUE if the query was performed successfully.
1329 	 */
1330 	public bool queryDefault(ObjectGst parent, Query query)
1331 	{
1332 		return gst_pad_query_default(gstPad, (parent is null) ? null : parent.getObjectGstStruct(), (query is null) ? null : query.getQueryStruct()) != 0;
1333 	}
1334 
1335 	/**
1336 	 * Queries a pad for the total stream duration.
1337 	 *
1338 	 * Params:
1339 	 *     format = the #GstFormat requested
1340 	 *     duration = a location in which to store the total
1341 	 *         duration, or %NULL.
1342 	 *
1343 	 * Return: %TRUE if the query could be performed.
1344 	 */
1345 	public bool queryDuration(GstFormat format, out long duration)
1346 	{
1347 		return gst_pad_query_duration(gstPad, format, &duration) != 0;
1348 	}
1349 
1350 	/**
1351 	 * Queries a pad for the stream position.
1352 	 *
1353 	 * Params:
1354 	 *     format = the #GstFormat requested
1355 	 *     cur = A location in which to store the current position, or %NULL.
1356 	 *
1357 	 * Return: %TRUE if the query could be performed.
1358 	 */
1359 	public bool queryPosition(GstFormat format, out long cur)
1360 	{
1361 		return gst_pad_query_position(gstPad, format, &cur) != 0;
1362 	}
1363 
1364 	/**
1365 	 * Remove the probe with @id from @pad.
1366 	 *
1367 	 * MT safe.
1368 	 *
1369 	 * Params:
1370 	 *     id = the probe id to remove
1371 	 */
1372 	public void removeProbe(gulong id)
1373 	{
1374 		gst_pad_remove_probe(gstPad, id);
1375 	}
1376 
1377 	/**
1378 	 * Sends the event to the pad. This function can be used
1379 	 * by applications to send events in the pipeline.
1380 	 *
1381 	 * If @pad is a source pad, @event should be an upstream event. If @pad is a
1382 	 * sink pad, @event should be a downstream event. For example, you would not
1383 	 * send a #GST_EVENT_EOS on a src pad; EOS events only propagate downstream.
1384 	 * Furthermore, some downstream events have to be serialized with data flow,
1385 	 * like EOS, while some can travel out-of-band, like #GST_EVENT_FLUSH_START. If
1386 	 * the event needs to be serialized with data flow, this function will take the
1387 	 * pad's stream lock while calling its event function.
1388 	 *
1389 	 * To find out whether an event type is upstream, downstream, or downstream and
1390 	 * serialized, see #GstEventTypeFlags, gst_event_type_get_flags(),
1391 	 * #GST_EVENT_IS_UPSTREAM, #GST_EVENT_IS_DOWNSTREAM, and
1392 	 * #GST_EVENT_IS_SERIALIZED. Note that in practice that an application or
1393 	 * plugin doesn't need to bother itself with this information; the core handles
1394 	 * all necessary locks and checks.
1395 	 *
1396 	 * This function takes ownership of the provided event so you should
1397 	 * gst_event_ref() it if you want to reuse the event after this call.
1398 	 *
1399 	 * Params:
1400 	 *     event = the #GstEvent to send to the pad.
1401 	 *
1402 	 * Return: %TRUE if the event was handled.
1403 	 */
1404 	public bool sendEvent(Event event)
1405 	{
1406 		return gst_pad_send_event(gstPad, (event is null) ? null : event.getEventStruct()) != 0;
1407 	}
1408 
1409 	/**
1410 	 * Sets the given activate function for @pad. The activate function will
1411 	 * dispatch to gst_pad_activate_mode() to perform the actual activation.
1412 	 * Only makes sense to set on sink pads.
1413 	 *
1414 	 * Call this function if your sink pad can start a pull-based task.
1415 	 *
1416 	 * Params:
1417 	 *     activate = the #GstPadActivateFunction to set.
1418 	 *     userData = user_data passed to @notify
1419 	 *     notify = notify called when @activate will not be used anymore.
1420 	 */
1421 	public void setActivateFunctionFull(GstPadActivateFunction activate, void* userData, GDestroyNotify notify)
1422 	{
1423 		gst_pad_set_activate_function_full(gstPad, activate, userData, notify);
1424 	}
1425 
1426 	/**
1427 	 * Sets the given activate_mode function for the pad. An activate_mode function
1428 	 * prepares the element for data passing.
1429 	 *
1430 	 * Params:
1431 	 *     activatemode = the #GstPadActivateModeFunction to set.
1432 	 *     userData = user_data passed to @notify
1433 	 *     notify = notify called when @activatemode will not be used anymore.
1434 	 */
1435 	public void setActivatemodeFunctionFull(GstPadActivateModeFunction activatemode, void* userData, GDestroyNotify notify)
1436 	{
1437 		gst_pad_set_activatemode_function_full(gstPad, activatemode, userData, notify);
1438 	}
1439 
1440 	/**
1441 	 * Activates or deactivates the given pad.
1442 	 * Normally called from within core state change functions.
1443 	 *
1444 	 * If @active, makes sure the pad is active. If it is already active, either in
1445 	 * push or pull mode, just return. Otherwise dispatches to the pad's activate
1446 	 * function to perform the actual activation.
1447 	 *
1448 	 * If not @active, calls gst_pad_activate_mode() with the pad's current mode
1449 	 * and a %FALSE argument.
1450 	 *
1451 	 * Params:
1452 	 *     active = whether or not the pad should be active.
1453 	 *
1454 	 * Return: %TRUE if the operation was successful.
1455 	 *
1456 	 *     MT safe.
1457 	 */
1458 	public bool setActive(bool active)
1459 	{
1460 		return gst_pad_set_active(gstPad, active) != 0;
1461 	}
1462 
1463 	/**
1464 	 * Sets the given chain function for the pad. The chain function is called to
1465 	 * process a #GstBuffer input buffer. see #GstPadChainFunction for more details.
1466 	 *
1467 	 * Params:
1468 	 *     chain = the #GstPadChainFunction to set.
1469 	 *     userData = user_data passed to @notify
1470 	 *     notify = notify called when @chain will not be used anymore.
1471 	 */
1472 	public void setChainFunctionFull(GstPadChainFunction chain, void* userData, GDestroyNotify notify)
1473 	{
1474 		gst_pad_set_chain_function_full(gstPad, chain, userData, notify);
1475 	}
1476 
1477 	/**
1478 	 * Sets the given chain list function for the pad. The chainlist function is
1479 	 * called to process a #GstBufferList input buffer list. See
1480 	 * #GstPadChainListFunction for more details.
1481 	 *
1482 	 * Params:
1483 	 *     chainlist = the #GstPadChainListFunction to set.
1484 	 *     userData = user_data passed to @notify
1485 	 *     notify = notify called when @chainlist will not be used anymore.
1486 	 */
1487 	public void setChainListFunctionFull(GstPadChainListFunction chainlist, void* userData, GDestroyNotify notify)
1488 	{
1489 		gst_pad_set_chain_list_function_full(gstPad, chainlist, userData, notify);
1490 	}
1491 
1492 	/**
1493 	 * Set the given private data gpointer on the pad.
1494 	 * This function can only be used by the element that owns the pad.
1495 	 * No locking is performed in this function.
1496 	 *
1497 	 * Params:
1498 	 *     priv = The private data to attach to the pad.
1499 	 */
1500 	public void setElementPrivate(void* priv)
1501 	{
1502 		gst_pad_set_element_private(gstPad, priv);
1503 	}
1504 
1505 	/**
1506 	 * Sets the given event handler for the pad.
1507 	 *
1508 	 * Params:
1509 	 *     event = the #GstPadEventFullFunction to set.
1510 	 *     userData = user_data passed to @notify
1511 	 *     notify = notify called when @event will not be used anymore.
1512 	 *
1513 	 * Since: 1.8
1514 	 */
1515 	public void setEventFullFunctionFull(GstPadEventFullFunction event, void* userData, GDestroyNotify notify)
1516 	{
1517 		gst_pad_set_event_full_function_full(gstPad, event, userData, notify);
1518 	}
1519 
1520 	/**
1521 	 * Sets the given event handler for the pad.
1522 	 *
1523 	 * Params:
1524 	 *     event = the #GstPadEventFunction to set.
1525 	 *     userData = user_data passed to @notify
1526 	 *     notify = notify called when @event will not be used anymore.
1527 	 */
1528 	public void setEventFunctionFull(GstPadEventFunction event, void* userData, GDestroyNotify notify)
1529 	{
1530 		gst_pad_set_event_function_full(gstPad, event, userData, notify);
1531 	}
1532 
1533 	/**
1534 	 * Sets the given getrange function for the pad. The getrange function is
1535 	 * called to produce a new #GstBuffer to start the processing pipeline. see
1536 	 * #GstPadGetRangeFunction for a description of the getrange function.
1537 	 *
1538 	 * Params:
1539 	 *     get = the #GstPadGetRangeFunction to set.
1540 	 *     userData = user_data passed to @notify
1541 	 *     notify = notify called when @get will not be used anymore.
1542 	 */
1543 	public void setGetrangeFunctionFull(GstPadGetRangeFunction get, void* userData, GDestroyNotify notify)
1544 	{
1545 		gst_pad_set_getrange_function_full(gstPad, get, userData, notify);
1546 	}
1547 
1548 	/**
1549 	 * Sets the given internal link iterator function for the pad.
1550 	 *
1551 	 * Params:
1552 	 *     iterintlink = the #GstPadIterIntLinkFunction to set.
1553 	 *     userData = user_data passed to @notify
1554 	 *     notify = notify called when @iterintlink will not be used anymore.
1555 	 */
1556 	public void setIterateInternalLinksFunctionFull(GstPadIterIntLinkFunction iterintlink, void* userData, GDestroyNotify notify)
1557 	{
1558 		gst_pad_set_iterate_internal_links_function_full(gstPad, iterintlink, userData, notify);
1559 	}
1560 
1561 	/**
1562 	 * Sets the given link function for the pad. It will be called when
1563 	 * the pad is linked with another pad.
1564 	 *
1565 	 * The return value #GST_PAD_LINK_OK should be used when the connection can be
1566 	 * made.
1567 	 *
1568 	 * The return value #GST_PAD_LINK_REFUSED should be used when the connection
1569 	 * cannot be made for some reason.
1570 	 *
1571 	 * If @link is installed on a source pad, it should call the #GstPadLinkFunction
1572 	 * of the peer sink pad, if present.
1573 	 *
1574 	 * Params:
1575 	 *     link = the #GstPadLinkFunction to set.
1576 	 *     userData = user_data passed to @notify
1577 	 *     notify = notify called when @link will not be used anymore.
1578 	 */
1579 	public void setLinkFunctionFull(GstPadLinkFunction link, void* userData, GDestroyNotify notify)
1580 	{
1581 		gst_pad_set_link_function_full(gstPad, link, userData, notify);
1582 	}
1583 
1584 	/**
1585 	 * Set the offset that will be applied to the running time of @pad.
1586 	 *
1587 	 * Params:
1588 	 *     offset = the offset
1589 	 */
1590 	public void setOffset(long offset)
1591 	{
1592 		gst_pad_set_offset(gstPad, offset);
1593 	}
1594 
1595 	/**
1596 	 * Set the given query function for the pad.
1597 	 *
1598 	 * Params:
1599 	 *     query = the #GstPadQueryFunction to set.
1600 	 *     userData = user_data passed to @notify
1601 	 *     notify = notify called when @query will not be used anymore.
1602 	 */
1603 	public void setQueryFunctionFull(GstPadQueryFunction query, void* userData, GDestroyNotify notify)
1604 	{
1605 		gst_pad_set_query_function_full(gstPad, query, userData, notify);
1606 	}
1607 
1608 	/**
1609 	 * Sets the given unlink function for the pad. It will be called
1610 	 * when the pad is unlinked.
1611 	 *
1612 	 * Params:
1613 	 *     unlink = the #GstPadUnlinkFunction to set.
1614 	 *     userData = user_data passed to @notify
1615 	 *     notify = notify called when @unlink will not be used anymore.
1616 	 */
1617 	public void setUnlinkFunctionFull(GstPadUnlinkFunction unlink, void* userData, GDestroyNotify notify)
1618 	{
1619 		gst_pad_set_unlink_function_full(gstPad, unlink, userData, notify);
1620 	}
1621 
1622 	/**
1623 	 * Starts a task that repeatedly calls @func with @user_data. This function
1624 	 * is mostly used in pad activation functions to start the dataflow.
1625 	 * The #GST_PAD_STREAM_LOCK of @pad will automatically be acquired
1626 	 * before @func is called.
1627 	 *
1628 	 * Params:
1629 	 *     func = the task function to call
1630 	 *     userData = user data passed to the task function
1631 	 *     notify = called when @user_data is no longer referenced
1632 	 *
1633 	 * Return: a %TRUE if the task could be started.
1634 	 */
1635 	public bool startTask(GstTaskFunction func, void* userData, GDestroyNotify notify)
1636 	{
1637 		return gst_pad_start_task(gstPad, func, userData, notify) != 0;
1638 	}
1639 
1640 	/**
1641 	 * Iterates all sticky events on @pad and calls @foreach_func for every
1642 	 * event. If @foreach_func returns %FALSE the iteration is immediately stopped.
1643 	 *
1644 	 * Params:
1645 	 *     foreachFunc = the #GstPadStickyEventsForeachFunction that
1646 	 *         should be called for every event.
1647 	 *     userData = the optional user data.
1648 	 */
1649 	public void stickyEventsForeach(GstPadStickyEventsForeachFunction foreachFunc, void* userData)
1650 	{
1651 		gst_pad_sticky_events_foreach(gstPad, foreachFunc, userData);
1652 	}
1653 
1654 	/**
1655 	 * Stop the task of @pad. This function will also make sure that the
1656 	 * function executed by the task will effectively stop if not called
1657 	 * from the GstTaskFunction.
1658 	 *
1659 	 * This function will deadlock if called from the GstTaskFunction of
1660 	 * the task. Use gst_task_pause() instead.
1661 	 *
1662 	 * Regardless of whether the pad has a task, the stream lock is acquired and
1663 	 * released so as to ensure that streaming through this pad has finished.
1664 	 *
1665 	 * Return: a %TRUE if the task could be stopped or %FALSE on error.
1666 	 */
1667 	public bool stopTask()
1668 	{
1669 		return gst_pad_stop_task(gstPad) != 0;
1670 	}
1671 
1672 	/**
1673 	 * Store the sticky @event on @pad
1674 	 *
1675 	 * Params:
1676 	 *     event = a #GstEvent
1677 	 *
1678 	 * Return: #GST_FLOW_OK on success, #GST_FLOW_FLUSHING when the pad
1679 	 *     was flushing or #GST_FLOW_EOS when the pad was EOS.
1680 	 *
1681 	 * Since: 1.2
1682 	 */
1683 	public GstFlowReturn storeStickyEvent(Event event)
1684 	{
1685 		return gst_pad_store_sticky_event(gstPad, (event is null) ? null : event.getEventStruct());
1686 	}
1687 
1688 	/**
1689 	 * Unlinks the source pad from the sink pad. Will emit the #GstPad::unlinked
1690 	 * signal on both pads.
1691 	 *
1692 	 * Params:
1693 	 *     sinkpad = the sink #GstPad to unlink.
1694 	 *
1695 	 * Return: %TRUE if the pads were unlinked. This function returns %FALSE if
1696 	 *     the pads were not linked together.
1697 	 *
1698 	 *     MT safe.
1699 	 */
1700 	public bool unlink(Pad sinkpad)
1701 	{
1702 		return gst_pad_unlink(gstPad, (sinkpad is null) ? null : sinkpad.getPadStruct()) != 0;
1703 	}
1704 
1705 	/**
1706 	 * A helper function you can use that sets the FIXED_CAPS flag
1707 	 * This way the default CAPS query will always return the negotiated caps
1708 	 * or in case the pad is not negotiated, the padtemplate caps.
1709 	 *
1710 	 * The negotiated caps are the caps of the last CAPS event that passed on the
1711 	 * pad. Use this function on a pad that, once it negotiated to a CAPS, cannot
1712 	 * be renegotiated to something else.
1713 	 */
1714 	public void useFixedCaps()
1715 	{
1716 		gst_pad_use_fixed_caps(gstPad);
1717 	}
1718 
1719 	int[string] connectedSignals;
1720 
1721 	void delegate(Pad, Pad)[] onLinkedListeners;
1722 	/**
1723 	 * Signals that a pad has been linked to the peer pad.
1724 	 *
1725 	 * Params:
1726 	 *     peer = the peer pad that has been connected
1727 	 */
1728 	void addOnLinked(void delegate(Pad, Pad) dlg, ConnectFlags connectFlags=cast(ConnectFlags)0)
1729 	{
1730 		if ( "linked" !in connectedSignals )
1731 		{
1732 			Signals.connectData(
1733 				this,
1734 				"linked",
1735 				cast(GCallback)&callBackLinked,
1736 				cast(void*)this,
1737 				null,
1738 				connectFlags);
1739 			connectedSignals["linked"] = 1;
1740 		}
1741 		onLinkedListeners ~= dlg;
1742 	}
1743 	extern(C) static void callBackLinked(GstPad* padStruct, GstPad* peer, Pad _pad)
1744 	{
1745 		foreach ( void delegate(Pad, Pad) dlg; _pad.onLinkedListeners )
1746 		{
1747 			dlg(ObjectG.getDObject!(Pad)(peer), _pad);
1748 		}
1749 	}
1750 
1751 	void delegate(Pad, Pad)[] onUnlinkedListeners;
1752 	/**
1753 	 * Signals that a pad has been unlinked from the peer pad.
1754 	 *
1755 	 * Params:
1756 	 *     peer = the peer pad that has been disconnected
1757 	 */
1758 	void addOnUnlinked(void delegate(Pad, Pad) dlg, ConnectFlags connectFlags=cast(ConnectFlags)0)
1759 	{
1760 		if ( "unlinked" !in connectedSignals )
1761 		{
1762 			Signals.connectData(
1763 				this,
1764 				"unlinked",
1765 				cast(GCallback)&callBackUnlinked,
1766 				cast(void*)this,
1767 				null,
1768 				connectFlags);
1769 			connectedSignals["unlinked"] = 1;
1770 		}
1771 		onUnlinkedListeners ~= dlg;
1772 	}
1773 	extern(C) static void callBackUnlinked(GstPad* padStruct, GstPad* peer, Pad _pad)
1774 	{
1775 		foreach ( void delegate(Pad, Pad) dlg; _pad.onUnlinkedListeners )
1776 		{
1777 			dlg(ObjectG.getDObject!(Pad)(peer), _pad);
1778 		}
1779 	}
1780 
1781 	/**
1782 	 * Gets a string representing the given flow return.
1783 	 *
1784 	 * Params:
1785 	 *     ret = a #GstFlowReturn to get the name of.
1786 	 *
1787 	 * Return: a static string with the name of the flow return.
1788 	 */
1789 	public static string flowGetName(GstFlowReturn ret)
1790 	{
1791 		return Str.toString(gst_flow_get_name(ret));
1792 	}
1793 
1794 	/**
1795 	 * Get the unique quark for the given GstFlowReturn.
1796 	 *
1797 	 * Params:
1798 	 *     ret = a #GstFlowReturn to get the quark of.
1799 	 *
1800 	 * Return: the quark associated with the flow return or 0 if an
1801 	 *     invalid return was specified.
1802 	 */
1803 	public static GQuark flowToQuark(GstFlowReturn ret)
1804 	{
1805 		return gst_flow_to_quark(ret);
1806 	}
1807 
1808 	/**
1809 	 * Return the name of a pad mode, for use in debug messages mostly.
1810 	 *
1811 	 * Params:
1812 	 *     mode = the pad mode
1813 	 *
1814 	 * Return: short mnemonic for pad mode @mode
1815 	 */
1816 	public static string modeGetName(GstPadMode mode)
1817 	{
1818 		return Str.toString(gst_pad_mode_get_name(mode));
1819 	}
1820 }