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 gstreamer.Stream;
42 private import gstreamer.c.functions;
43 public  import gstreamer.c.types;
44 public  import gstreamerc.gstreamertypes;
45 private import std.algorithm;
46 
47 
48 /**
49  * A #GstElement is linked to other elements via "pads", which are extremely
50  * light-weight generic link points.
51  * 
52  * Pads have a #GstPadDirection, source pads produce data, sink pads consume
53  * data.
54  * 
55  * Pads are typically created from a #GstPadTemplate with
56  * gst_pad_new_from_template() and are then added to a #GstElement. This usually
57  * happens when the element is created but it can also happen dynamically based
58  * on the data that the element is processing or based on the pads that the
59  * application requests.
60  * 
61  * Pads without pad templates can be created with gst_pad_new(),
62  * which takes a direction and a name as an argument.  If the name is %NULL,
63  * then a guaranteed unique name will be assigned to it.
64  * 
65  * A #GstElement creating a pad will typically use the various
66  * gst_pad_set_*_function() calls to register callbacks for events, queries or
67  * dataflow on the pads.
68  * 
69  * gst_pad_get_parent() will retrieve the #GstElement that owns the pad.
70  * 
71  * After two pads are retrieved from an element by gst_element_get_static_pad(),
72  * the pads can be linked with gst_pad_link(). (For quick links,
73  * you can also use gst_element_link(), which will make the obvious
74  * link for you if it's straightforward.). Pads can be unlinked again with
75  * gst_pad_unlink(). gst_pad_get_peer() can be used to check what the pad is
76  * linked to.
77  * 
78  * Before dataflow is possible on the pads, they need to be activated with
79  * gst_pad_set_active().
80  * 
81  * gst_pad_query() and gst_pad_peer_query() can be used to query various
82  * properties of the pad and the stream.
83  * 
84  * To send a #GstEvent on a pad, use gst_pad_send_event() and
85  * gst_pad_push_event(). Some events will be sticky on the pad, meaning that
86  * after they pass on the pad they can be queried later with
87  * gst_pad_get_sticky_event() and gst_pad_sticky_events_foreach().
88  * gst_pad_get_current_caps() and gst_pad_has_current_caps() are convenience
89  * functions to query the current sticky CAPS event on a pad.
90  * 
91  * GstElements will use gst_pad_push() and gst_pad_pull_range() to push out
92  * or pull in a buffer.
93  * 
94  * The dataflow, events and queries that happen on a pad can be monitored with
95  * probes that can be installed with gst_pad_add_probe(). gst_pad_is_blocked()
96  * can be used to check if a block probe is installed on the pad.
97  * gst_pad_is_blocking() checks if the blocking probe is currently blocking the
98  * pad. gst_pad_remove_probe() is used to remove a previously installed probe
99  * and unblock blocking probes if any.
100  * 
101  * Pad have an offset that can be retrieved with gst_pad_get_offset(). This
102  * offset will be applied to the running_time of all data passing over the pad.
103  * gst_pad_set_offset() can be used to change the offset.
104  * 
105  * Convenience functions exist to start, pause and stop the task on a pad with
106  * gst_pad_start_task(), gst_pad_pause_task() and gst_pad_stop_task()
107  * respectively.
108  */
109 public class Pad : ObjectGst
110 {
111 	/** the main Gtk struct */
112 	protected GstPad* gstPad;
113 
114 	/** Get the main Gtk struct */
115 	public GstPad* getPadStruct(bool transferOwnership = false)
116 	{
117 		if (transferOwnership)
118 			ownedRef = false;
119 		return gstPad;
120 	}
121 
122 	/** the main Gtk struct as a void* */
123 	protected override void* getStruct()
124 	{
125 		return cast(void*)gstPad;
126 	}
127 
128 	/**
129 	 * Sets our main struct and passes it to the parent class.
130 	 */
131 	public this (GstPad* gstPad, bool ownedRef = false)
132 	{
133 		this.gstPad = gstPad;
134 		super(cast(GstObject*)gstPad, ownedRef);
135 	}
136 
137 	/**
138 	 * Queries a pad for the stream position.
139 	 * This is a convenience function for gstreamerD.
140 	 * Returns:
141 	 *  The current position in nanoseconds - GstFormat.TIME.
142 	 */
143 	public long queryPosition()
144 	{
145 		long cur_pos;
146 		queryPosition( GstFormat.TIME, cur_pos );
147 		return cur_pos;
148 	}
149 
150 	/**
151 	 * Queries a pad for the stream duration.
152 	 * This is a convenience function for gstreamerD.
153 	 * Returns:
154 	 *  The duration in nanoseconds - GstFormat.TIME.
155 	 */
156 	public long queryDuration()
157 	{
158 		long cur_dur;
159 		queryDuration( GstFormat.TIME, cur_dur );
160 		return cur_dur;
161 	}
162 
163 	/**
164 	 */
165 
166 	/** */
167 	public static GType getType()
168 	{
169 		return gst_pad_get_type();
170 	}
171 
172 	/**
173 	 * Creates a new pad with the given name in the given direction.
174 	 * If name is %NULL, a guaranteed unique name (across all pads)
175 	 * will be assigned.
176 	 * This function makes a copy of the name so you can safely free the name.
177 	 *
178 	 * Params:
179 	 *     name = the name of the new pad.
180 	 *     direction = the #GstPadDirection of the pad.
181 	 *
182 	 * Returns: a new #GstPad, or %NULL in
183 	 *     case of an error.
184 	 *
185 	 *     MT safe.
186 	 *
187 	 * Throws: ConstructionException GTK+ fails to create the object.
188 	 */
189 	public this(string name, GstPadDirection direction)
190 	{
191 		auto p = gst_pad_new(Str.toStringz(name), direction);
192 
193 		if(p is null)
194 		{
195 			throw new ConstructionException("null returned by new");
196 		}
197 
198 		this(cast(GstPad*) p);
199 	}
200 
201 	/**
202 	 * Creates a new pad with the given name from the given static template.
203 	 * If name is %NULL, a guaranteed unique name (across all pads)
204 	 * will be assigned.
205 	 * This function makes a copy of the name so you can safely free the name.
206 	 *
207 	 * Params:
208 	 *     templ = the #GstStaticPadTemplate to use
209 	 *     name = the name of the pad
210 	 *
211 	 * Returns: a new #GstPad, or %NULL in
212 	 *     case of an error.
213 	 *
214 	 * Throws: ConstructionException GTK+ fails to create the object.
215 	 */
216 	public this(StaticPadTemplate templ, string name)
217 	{
218 		auto p = gst_pad_new_from_static_template((templ is null) ? null : templ.getStaticPadTemplateStruct(), Str.toStringz(name));
219 
220 		if(p is null)
221 		{
222 			throw new ConstructionException("null returned by new_from_static_template");
223 		}
224 
225 		this(cast(GstPad*) p);
226 	}
227 
228 	/**
229 	 * Creates a new pad with the given name from the given template.
230 	 * If name is %NULL, a guaranteed unique name (across all pads)
231 	 * will be assigned.
232 	 * This function makes a copy of the name so you can safely free the name.
233 	 *
234 	 * Params:
235 	 *     templ = the pad template to use
236 	 *     name = the name of the pad
237 	 *
238 	 * Returns: a new #GstPad, or %NULL in
239 	 *     case of an error.
240 	 *
241 	 * Throws: ConstructionException GTK+ fails to create the object.
242 	 */
243 	public this(PadTemplate templ, string name)
244 	{
245 		auto p = gst_pad_new_from_template((templ is null) ? null : templ.getPadTemplateStruct(), Str.toStringz(name));
246 
247 		if(p is null)
248 		{
249 			throw new ConstructionException("null returned by new_from_template");
250 		}
251 
252 		this(cast(GstPad*) p);
253 	}
254 
255 	/**
256 	 * Gets a string representing the given pad-link return.
257 	 *
258 	 * Params:
259 	 *     ret = a #GstPadLinkReturn to get the name of.
260 	 *
261 	 * Returns: a static string with the name of the pad-link return.
262 	 *
263 	 * Since: 1.4
264 	 */
265 	public static string linkGetName(GstPadLinkReturn ret)
266 	{
267 		return Str.toString(gst_pad_link_get_name(ret));
268 	}
269 
270 	/**
271 	 * Activates or deactivates the given pad in @mode via dispatching to the
272 	 * pad's activatemodefunc. For use from within pad activation functions only.
273 	 *
274 	 * If you don't know what this is, you probably don't want to call it.
275 	 *
276 	 * Params:
277 	 *     mode = the requested activation mode
278 	 *     active = whether or not the pad should be active.
279 	 *
280 	 * Returns: %TRUE if the operation was successful.
281 	 *
282 	 *     MT safe.
283 	 */
284 	public bool activateMode(GstPadMode mode, bool active)
285 	{
286 		return gst_pad_activate_mode(gstPad, mode, active) != 0;
287 	}
288 
289 	/**
290 	 * Be notified of different states of pads. The provided callback is called for
291 	 * every state that matches @mask.
292 	 *
293 	 * Probes are called in groups: First GST_PAD_PROBE_TYPE_BLOCK probes are
294 	 * called, then others, then finally GST_PAD_PROBE_TYPE_IDLE. The only
295 	 * exception here are GST_PAD_PROBE_TYPE_IDLE probes that are called
296 	 * immediately if the pad is already idle while calling gst_pad_add_probe().
297 	 * In each of the groups, probes are called in the order in which they were
298 	 * added.
299 	 *
300 	 * Params:
301 	 *     mask = the probe mask
302 	 *     callback = #GstPadProbeCallback that will be called with notifications of
303 	 *         the pad state
304 	 *     userData = user data passed to the callback
305 	 *     destroyData = #GDestroyNotify for user_data
306 	 *
307 	 * Returns: an id or 0 if no probe is pending. The id can be used to remove the
308 	 *     probe with gst_pad_remove_probe(). When using GST_PAD_PROBE_TYPE_IDLE it can
309 	 *     happen that the probe can be run immediately and if the probe returns
310 	 *     GST_PAD_PROBE_REMOVE this functions returns 0.
311 	 *
312 	 *     MT safe.
313 	 */
314 	public gulong addProbe(GstPadProbeType mask, GstPadProbeCallback callback, void* userData, GDestroyNotify destroyData)
315 	{
316 		return gst_pad_add_probe(gstPad, mask, callback, userData, destroyData);
317 	}
318 
319 	/**
320 	 * Checks if the source pad and the sink pad are compatible so they can be
321 	 * linked.
322 	 *
323 	 * Params:
324 	 *     sinkpad = the sink #GstPad.
325 	 *
326 	 * Returns: %TRUE if the pads can be linked.
327 	 */
328 	public bool canLink(Pad sinkpad)
329 	{
330 		return gst_pad_can_link(gstPad, (sinkpad is null) ? null : sinkpad.getPadStruct()) != 0;
331 	}
332 
333 	/**
334 	 * Chain a buffer to @pad.
335 	 *
336 	 * The function returns #GST_FLOW_FLUSHING if the pad was flushing.
337 	 *
338 	 * If the buffer type is not acceptable for @pad (as negotiated with a
339 	 * preceding GST_EVENT_CAPS event), this function returns
340 	 * #GST_FLOW_NOT_NEGOTIATED.
341 	 *
342 	 * The function proceeds calling the chain function installed on @pad (see
343 	 * gst_pad_set_chain_function()) and the return value of that function is
344 	 * returned to the caller. #GST_FLOW_NOT_SUPPORTED is returned if @pad has no
345 	 * chain function.
346 	 *
347 	 * In all cases, success or failure, the caller loses its reference to @buffer
348 	 * after calling this function.
349 	 *
350 	 * Params:
351 	 *     buffer = the #GstBuffer to send, return GST_FLOW_ERROR
352 	 *         if not.
353 	 *
354 	 * Returns: a #GstFlowReturn from the pad.
355 	 *
356 	 *     MT safe.
357 	 */
358 	public GstFlowReturn chain(Buffer buffer)
359 	{
360 		return gst_pad_chain(gstPad, (buffer is null) ? null : buffer.getBufferStruct());
361 	}
362 
363 	/**
364 	 * Chain a bufferlist to @pad.
365 	 *
366 	 * The function returns #GST_FLOW_FLUSHING if the pad was flushing.
367 	 *
368 	 * If @pad was not negotiated properly with a CAPS event, this function
369 	 * returns #GST_FLOW_NOT_NEGOTIATED.
370 	 *
371 	 * The function proceeds calling the chainlist function installed on @pad (see
372 	 * gst_pad_set_chain_list_function()) and the return value of that function is
373 	 * returned to the caller. #GST_FLOW_NOT_SUPPORTED is returned if @pad has no
374 	 * chainlist function.
375 	 *
376 	 * In all cases, success or failure, the caller loses its reference to @list
377 	 * after calling this function.
378 	 *
379 	 * MT safe.
380 	 *
381 	 * Params:
382 	 *     list = the #GstBufferList to send, return GST_FLOW_ERROR
383 	 *         if not.
384 	 *
385 	 * Returns: a #GstFlowReturn from the pad.
386 	 */
387 	public GstFlowReturn chainList(BufferList list)
388 	{
389 		return gst_pad_chain_list(gstPad, (list is null) ? null : list.getBufferListStruct());
390 	}
391 
392 	/**
393 	 * Check and clear the #GST_PAD_FLAG_NEED_RECONFIGURE flag on @pad and return %TRUE
394 	 * if the flag was set.
395 	 *
396 	 * Returns: %TRUE is the GST_PAD_FLAG_NEED_RECONFIGURE flag was set on @pad.
397 	 */
398 	public bool checkReconfigure()
399 	{
400 		return gst_pad_check_reconfigure(gstPad) != 0;
401 	}
402 
403 	/**
404 	 * Creates a stream-id for the source #GstPad @pad by combining the
405 	 * upstream information with the optional @stream_id of the stream
406 	 * of @pad. @pad must have a parent #GstElement and which must have zero
407 	 * or one sinkpad. @stream_id can only be %NULL if the parent element
408 	 * of @pad has only a single source pad.
409 	 *
410 	 * This function generates an unique stream-id by getting the upstream
411 	 * stream-start event stream ID and appending @stream_id to it. If the
412 	 * element has no sinkpad it will generate an upstream stream-id by
413 	 * doing an URI query on the element and in the worst case just uses
414 	 * a random number. Source elements that don't implement the URI
415 	 * handler interface should ideally generate a unique, deterministic
416 	 * stream-id manually instead.
417 	 *
418 	 * Since stream IDs are sorted alphabetically, any numbers in the
419 	 * stream ID should be printed with a fixed number of characters,
420 	 * preceded by 0's, such as by using the format \%03u instead of \%u.
421 	 *
422 	 * Params:
423 	 *     parent = Parent #GstElement of @pad
424 	 *     streamId = The stream-id
425 	 *
426 	 * Returns: A stream-id for @pad. g_free() after usage.
427 	 */
428 	public string createStreamId(Element parent, string streamId)
429 	{
430 		auto retStr = gst_pad_create_stream_id(gstPad, (parent is null) ? null : parent.getElementStruct(), Str.toStringz(streamId));
431 
432 		scope(exit) Str.freeString(retStr);
433 		return Str.toString(retStr);
434 	}
435 
436 	/**
437 	 * Creates a stream-id for the source #GstPad @pad by combining the
438 	 * upstream information with the optional @stream_id of the stream
439 	 * of @pad. @pad must have a parent #GstElement and which must have zero
440 	 * or one sinkpad. @stream_id can only be %NULL if the parent element
441 	 * of @pad has only a single source pad.
442 	 *
443 	 * This function generates an unique stream-id by getting the upstream
444 	 * stream-start event stream ID and appending @stream_id to it. If the
445 	 * element has no sinkpad it will generate an upstream stream-id by
446 	 * doing an URI query on the element and in the worst case just uses
447 	 * a random number. Source elements that don't implement the URI
448 	 * handler interface should ideally generate a unique, deterministic
449 	 * stream-id manually instead.
450 	 *
451 	 * Params:
452 	 *     parent = Parent #GstElement of @pad
453 	 *     streamId = The stream-id
454 	 *     varArgs = parameters for the @stream_id format string
455 	 *
456 	 * Returns: A stream-id for @pad. g_free() after usage.
457 	 */
458 	public string createStreamIdPrintfValist(Element parent, string streamId, void* varArgs)
459 	{
460 		auto retStr = gst_pad_create_stream_id_printf_valist(gstPad, (parent is null) ? null : parent.getElementStruct(), Str.toStringz(streamId), varArgs);
461 
462 		scope(exit) Str.freeString(retStr);
463 		return Str.toString(retStr);
464 	}
465 
466 	/**
467 	 * Invokes the default event handler for the given pad.
468 	 *
469 	 * The EOS event will pause the task associated with @pad before it is forwarded
470 	 * to all internally linked pads,
471 	 *
472 	 * The event is sent to all pads internally linked to @pad. This function
473 	 * takes ownership of @event.
474 	 *
475 	 * Params:
476 	 *     parent = the parent of @pad or %NULL
477 	 *     event = the #GstEvent to handle.
478 	 *
479 	 * Returns: %TRUE if the event was sent successfully.
480 	 */
481 	public bool eventDefault(ObjectGst parent, Event event)
482 	{
483 		return gst_pad_event_default(gstPad, (parent is null) ? null : parent.getObjectGstStruct(), (event is null) ? null : event.getEventStruct()) != 0;
484 	}
485 
486 	/**
487 	 * Calls @forward for all internally linked pads of @pad. This function deals with
488 	 * dynamically changing internal pads and will make sure that the @forward
489 	 * function is only called once for each pad.
490 	 *
491 	 * When @forward returns %TRUE, no further pads will be processed.
492 	 *
493 	 * Params:
494 	 *     forward = a #GstPadForwardFunction
495 	 *     userData = user data passed to @forward
496 	 *
497 	 * Returns: %TRUE if one of the dispatcher functions returned %TRUE.
498 	 */
499 	public bool forward(GstPadForwardFunction forward, void* userData)
500 	{
501 		return gst_pad_forward(gstPad, forward, userData) != 0;
502 	}
503 
504 	/**
505 	 * Gets the capabilities of the allowed media types that can flow through
506 	 * @pad and its peer.
507 	 *
508 	 * The allowed capabilities is calculated as the intersection of the results of
509 	 * calling gst_pad_query_caps() on @pad and its peer. The caller owns a reference
510 	 * on the resulting caps.
511 	 *
512 	 * Returns: the allowed #GstCaps of the
513 	 *     pad link. Unref the caps when you no longer need it. This
514 	 *     function returns %NULL when @pad has no peer.
515 	 *
516 	 *     MT safe.
517 	 */
518 	public Caps getAllowedCaps()
519 	{
520 		auto p = gst_pad_get_allowed_caps(gstPad);
521 
522 		if(p is null)
523 		{
524 			return null;
525 		}
526 
527 		return ObjectG.getDObject!(Caps)(cast(GstCaps*) p, true);
528 	}
529 
530 	/**
531 	 * Gets the capabilities currently configured on @pad with the last
532 	 * #GST_EVENT_CAPS event.
533 	 *
534 	 * Returns: the current caps of the pad with
535 	 *     incremented ref-count or %NULL when pad has no caps. Unref after usage.
536 	 */
537 	public Caps getCurrentCaps()
538 	{
539 		auto p = gst_pad_get_current_caps(gstPad);
540 
541 		if(p is null)
542 		{
543 			return null;
544 		}
545 
546 		return ObjectG.getDObject!(Caps)(cast(GstCaps*) p, true);
547 	}
548 
549 	/**
550 	 * Gets the direction of the pad. The direction of the pad is
551 	 * decided at construction time so this function does not take
552 	 * the LOCK.
553 	 *
554 	 * Returns: the #GstPadDirection of the pad.
555 	 *
556 	 *     MT safe.
557 	 */
558 	public GstPadDirection getDirection()
559 	{
560 		return gst_pad_get_direction(gstPad);
561 	}
562 
563 	/**
564 	 * Gets the private data of a pad.
565 	 * No locking is performed in this function.
566 	 *
567 	 * Returns: a #gpointer to the private data.
568 	 */
569 	public void* getElementPrivate()
570 	{
571 		return gst_pad_get_element_private(gstPad);
572 	}
573 
574 	/**
575 	 * Gets the #GstFlowReturn return from the last data passed by this pad.
576 	 *
577 	 * Since: 1.4
578 	 */
579 	public GstFlowReturn getLastFlowReturn()
580 	{
581 		return gst_pad_get_last_flow_return(gstPad);
582 	}
583 
584 	/**
585 	 * Get the offset applied to the running time of @pad. @pad has to be a source
586 	 * pad.
587 	 *
588 	 * Returns: the offset.
589 	 */
590 	public long getOffset()
591 	{
592 		return gst_pad_get_offset(gstPad);
593 	}
594 
595 	/**
596 	 * Gets the template for @pad.
597 	 *
598 	 * Returns: the #GstPadTemplate from which
599 	 *     this pad was instantiated, or %NULL if this pad has no
600 	 *     template. Unref after usage.
601 	 */
602 	public PadTemplate getPadTemplate()
603 	{
604 		auto p = gst_pad_get_pad_template(gstPad);
605 
606 		if(p is null)
607 		{
608 			return null;
609 		}
610 
611 		return ObjectG.getDObject!(PadTemplate)(cast(GstPadTemplate*) p, true);
612 	}
613 
614 	/**
615 	 * Gets the capabilities for @pad's template.
616 	 *
617 	 * Returns: the #GstCaps of this pad template.
618 	 *     Unref after usage.
619 	 */
620 	public Caps getPadTemplateCaps()
621 	{
622 		auto p = gst_pad_get_pad_template_caps(gstPad);
623 
624 		if(p is null)
625 		{
626 			return null;
627 		}
628 
629 		return ObjectG.getDObject!(Caps)(cast(GstCaps*) p, true);
630 	}
631 
632 	/**
633 	 * Gets the parent of @pad, cast to a #GstElement. If a @pad has no parent or
634 	 * its parent is not an element, return %NULL.
635 	 *
636 	 * Returns: the parent of the pad. The
637 	 *     caller has a reference on the parent, so unref when you're finished
638 	 *     with it.
639 	 *
640 	 *     MT safe.
641 	 */
642 	public Element getParentElement()
643 	{
644 		auto p = gst_pad_get_parent_element(gstPad);
645 
646 		if(p is null)
647 		{
648 			return null;
649 		}
650 
651 		return ObjectG.getDObject!(Element)(cast(GstElement*) p, true);
652 	}
653 
654 	/**
655 	 * Gets the peer of @pad. This function refs the peer pad so
656 	 * you need to unref it after use.
657 	 *
658 	 * Returns: the peer #GstPad. Unref after usage.
659 	 *
660 	 *     MT safe.
661 	 */
662 	public Pad getPeer()
663 	{
664 		auto p = gst_pad_get_peer(gstPad);
665 
666 		if(p is null)
667 		{
668 			return null;
669 		}
670 
671 		return ObjectG.getDObject!(Pad)(cast(GstPad*) p, true);
672 	}
673 
674 	/**
675 	 * When @pad is flushing this function returns #GST_FLOW_FLUSHING
676 	 * immediately and @buffer is %NULL.
677 	 *
678 	 * Calls the getrange function of @pad, see #GstPadGetRangeFunction for a
679 	 * description of a getrange function. If @pad has no getrange function
680 	 * installed (see gst_pad_set_getrange_function()) this function returns
681 	 * #GST_FLOW_NOT_SUPPORTED.
682 	 *
683 	 * If @buffer points to a variable holding %NULL, a valid new #GstBuffer will be
684 	 * placed in @buffer when this function returns #GST_FLOW_OK. The new buffer
685 	 * must be freed with gst_buffer_unref() after usage.
686 	 *
687 	 * When @buffer points to a variable that points to a valid #GstBuffer, the
688 	 * buffer will be filled with the result data when this function returns
689 	 * #GST_FLOW_OK. If the provided buffer is larger than @size, only
690 	 * @size bytes will be filled in the result buffer and its size will be updated
691 	 * accordingly.
692 	 *
693 	 * Note that less than @size bytes can be returned in @buffer when, for example,
694 	 * an EOS condition is near or when @buffer is not large enough to hold @size
695 	 * bytes. The caller should check the result buffer size to get the result size.
696 	 *
697 	 * When this function returns any other result value than #GST_FLOW_OK, @buffer
698 	 * will be unchanged.
699 	 *
700 	 * This is a lowlevel function. Usually gst_pad_pull_range() is used.
701 	 *
702 	 * Params:
703 	 *     offset = The start offset of the buffer
704 	 *     size = The length of the buffer
705 	 *     buffer = a pointer to hold the #GstBuffer,
706 	 *         returns #GST_FLOW_ERROR if %NULL.
707 	 *
708 	 * Returns: a #GstFlowReturn from the pad.
709 	 *
710 	 *     MT safe.
711 	 */
712 	public GstFlowReturn getRange(ulong offset, uint size, out Buffer buffer)
713 	{
714 		GstBuffer* outbuffer = null;
715 
716 		auto p = gst_pad_get_range(gstPad, offset, size, &outbuffer);
717 
718 		buffer = ObjectG.getDObject!(Buffer)(outbuffer);
719 
720 		return p;
721 	}
722 
723 	/**
724 	 * Returns a new reference of the sticky event of type @event_type
725 	 * from the event.
726 	 *
727 	 * Params:
728 	 *     eventType = the #GstEventType that should be retrieved.
729 	 *     idx = the index of the event
730 	 *
731 	 * Returns: a #GstEvent of type
732 	 *     @event_type or %NULL when no event of @event_type was on
733 	 *     @pad. Unref after usage.
734 	 */
735 	public Event getStickyEvent(GstEventType eventType, uint idx)
736 	{
737 		auto p = gst_pad_get_sticky_event(gstPad, eventType, idx);
738 
739 		if(p is null)
740 		{
741 			return null;
742 		}
743 
744 		return ObjectG.getDObject!(Event)(cast(GstEvent*) p, true);
745 	}
746 
747 	/**
748 	 * Returns the current #GstStream for the @pad, or %NULL if none has been
749 	 * set yet, i.e. the pad has not received a stream-start event yet.
750 	 *
751 	 * This is a convenience wrapper around gst_pad_get_sticky_event() and
752 	 * gst_event_parse_stream().
753 	 *
754 	 * Returns: the current #GstStream for @pad, or %NULL.
755 	 *     unref the returned stream when no longer needed.
756 	 *
757 	 * Since: 1.10
758 	 */
759 	public Stream getStream()
760 	{
761 		auto p = gst_pad_get_stream(gstPad);
762 
763 		if(p is null)
764 		{
765 			return null;
766 		}
767 
768 		return ObjectG.getDObject!(Stream)(cast(GstStream*) p, true);
769 	}
770 
771 	/**
772 	 * Returns the current stream-id for the @pad, or %NULL if none has been
773 	 * set yet, i.e. the pad has not received a stream-start event yet.
774 	 *
775 	 * This is a convenience wrapper around gst_pad_get_sticky_event() and
776 	 * gst_event_parse_stream_start().
777 	 *
778 	 * The returned stream-id string should be treated as an opaque string, its
779 	 * contents should not be interpreted.
780 	 *
781 	 * Returns: a newly-allocated copy of the stream-id for
782 	 *     @pad, or %NULL.  g_free() the returned string when no longer
783 	 *     needed.
784 	 *
785 	 * Since: 1.2
786 	 */
787 	public string getStreamId()
788 	{
789 		auto retStr = gst_pad_get_stream_id(gstPad);
790 
791 		scope(exit) Str.freeString(retStr);
792 		return Str.toString(retStr);
793 	}
794 
795 	/**
796 	 * Get @pad task state. If no task is currently
797 	 * set, #GST_TASK_STOPPED is returned.
798 	 *
799 	 * Returns: The current state of @pad's task.
800 	 *
801 	 * Since: 1.12
802 	 */
803 	public GstTaskState getTaskState()
804 	{
805 		return gst_pad_get_task_state(gstPad);
806 	}
807 
808 	/**
809 	 * Check if @pad has caps set on it with a #GST_EVENT_CAPS event.
810 	 *
811 	 * Returns: %TRUE when @pad has caps associated with it.
812 	 */
813 	public bool hasCurrentCaps()
814 	{
815 		return gst_pad_has_current_caps(gstPad) != 0;
816 	}
817 
818 	/**
819 	 * Query if a pad is active
820 	 *
821 	 * Returns: %TRUE if the pad is active.
822 	 *
823 	 *     MT safe.
824 	 */
825 	public bool isActive()
826 	{
827 		return gst_pad_is_active(gstPad) != 0;
828 	}
829 
830 	/**
831 	 * Checks if the pad is blocked or not. This function returns the
832 	 * last requested state of the pad. It is not certain that the pad
833 	 * is actually blocking at this point (see gst_pad_is_blocking()).
834 	 *
835 	 * Returns: %TRUE if the pad is blocked.
836 	 *
837 	 *     MT safe.
838 	 */
839 	public bool isBlocked()
840 	{
841 		return gst_pad_is_blocked(gstPad) != 0;
842 	}
843 
844 	/**
845 	 * Checks if the pad is blocking or not. This is a guaranteed state
846 	 * of whether the pad is actually blocking on a #GstBuffer or a #GstEvent.
847 	 *
848 	 * Returns: %TRUE if the pad is blocking.
849 	 *
850 	 *     MT safe.
851 	 */
852 	public bool isBlocking()
853 	{
854 		return gst_pad_is_blocking(gstPad) != 0;
855 	}
856 
857 	/**
858 	 * Checks if a @pad is linked to another pad or not.
859 	 *
860 	 * Returns: %TRUE if the pad is linked, %FALSE otherwise.
861 	 *
862 	 *     MT safe.
863 	 */
864 	public bool isLinked()
865 	{
866 		return gst_pad_is_linked(gstPad) != 0;
867 	}
868 
869 	/**
870 	 * Gets an iterator for the pads to which the given pad is linked to inside
871 	 * of the parent element.
872 	 *
873 	 * Each #GstPad element yielded by the iterator will have its refcount increased,
874 	 * so unref after use.
875 	 *
876 	 * Free-function: gst_iterator_free
877 	 *
878 	 * Returns: a new #GstIterator of #GstPad
879 	 *     or %NULL when the pad does not have an iterator function
880 	 *     configured. Use gst_iterator_free() after usage.
881 	 */
882 	public Iterator iterateInternalLinks()
883 	{
884 		auto p = gst_pad_iterate_internal_links(gstPad);
885 
886 		if(p is null)
887 		{
888 			return null;
889 		}
890 
891 		return ObjectG.getDObject!(Iterator)(cast(GstIterator*) p, true);
892 	}
893 
894 	/**
895 	 * Iterate the list of pads to which the given pad is linked to inside of
896 	 * the parent element.
897 	 * This is the default handler, and thus returns an iterator of all of the
898 	 * pads inside the parent element with opposite direction.
899 	 *
900 	 * The caller must free this iterator after use with gst_iterator_free().
901 	 *
902 	 * Params:
903 	 *     parent = the parent of @pad or %NULL
904 	 *
905 	 * Returns: a #GstIterator of #GstPad, or %NULL if @pad
906 	 *     has no parent. Unref each returned pad with gst_object_unref().
907 	 */
908 	public Iterator iterateInternalLinksDefault(ObjectGst parent)
909 	{
910 		auto p = gst_pad_iterate_internal_links_default(gstPad, (parent is null) ? null : parent.getObjectGstStruct());
911 
912 		if(p is null)
913 		{
914 			return null;
915 		}
916 
917 		return ObjectG.getDObject!(Iterator)(cast(GstIterator*) p, true);
918 	}
919 
920 	/**
921 	 * Links the source pad and the sink pad.
922 	 *
923 	 * Params:
924 	 *     sinkpad = the sink #GstPad to link.
925 	 *
926 	 * Returns: A result code indicating if the connection worked or
927 	 *     what went wrong.
928 	 *
929 	 *     MT Safe.
930 	 */
931 	public GstPadLinkReturn link(Pad sinkpad)
932 	{
933 		return gst_pad_link(gstPad, (sinkpad is null) ? null : sinkpad.getPadStruct());
934 	}
935 
936 	/**
937 	 * Links the source pad and the sink pad.
938 	 *
939 	 * This variant of #gst_pad_link provides a more granular control on the
940 	 * checks being done when linking. While providing some considerable speedups
941 	 * the caller of this method must be aware that wrong usage of those flags
942 	 * can cause severe issues. Refer to the documentation of #GstPadLinkCheck
943 	 * for more information.
944 	 *
945 	 * MT Safe.
946 	 *
947 	 * Params:
948 	 *     sinkpad = the sink #GstPad to link.
949 	 *     flags = the checks to validate when linking
950 	 *
951 	 * Returns: A result code indicating if the connection worked or
952 	 *     what went wrong.
953 	 */
954 	public GstPadLinkReturn linkFull(Pad sinkpad, GstPadLinkCheck flags)
955 	{
956 		return gst_pad_link_full(gstPad, (sinkpad is null) ? null : sinkpad.getPadStruct(), flags);
957 	}
958 
959 	/**
960 	 * Links @src to @sink, creating any #GstGhostPad's in between as necessary.
961 	 *
962 	 * This is a convenience function to save having to create and add intermediate
963 	 * #GstGhostPad's as required for linking across #GstBin boundaries.
964 	 *
965 	 * If @src or @sink pads don't have parent elements or do not share a common
966 	 * ancestor, the link will fail.
967 	 *
968 	 * Params:
969 	 *     sink = a #GstPad
970 	 *
971 	 * Returns: whether the link succeeded.
972 	 *
973 	 * Since: 1.10
974 	 */
975 	public bool linkMaybeGhosting(Pad sink)
976 	{
977 		return gst_pad_link_maybe_ghosting(gstPad, (sink is null) ? null : sink.getPadStruct()) != 0;
978 	}
979 
980 	/**
981 	 * Links @src to @sink, creating any #GstGhostPad's in between as necessary.
982 	 *
983 	 * This is a convenience function to save having to create and add intermediate
984 	 * #GstGhostPad's as required for linking across #GstBin boundaries.
985 	 *
986 	 * If @src or @sink pads don't have parent elements or do not share a common
987 	 * ancestor, the link will fail.
988 	 *
989 	 * Calling gst_pad_link_maybe_ghosting_full() with
990 	 * @flags == %GST_PAD_LINK_CHECK_DEFAULT is the recommended way of linking
991 	 * pads with safety checks applied.
992 	 *
993 	 * Params:
994 	 *     sink = a #GstPad
995 	 *     flags = some #GstPadLinkCheck flags
996 	 *
997 	 * Returns: whether the link succeeded.
998 	 *
999 	 * Since: 1.10
1000 	 */
1001 	public bool linkMaybeGhostingFull(Pad sink, GstPadLinkCheck flags)
1002 	{
1003 		return gst_pad_link_maybe_ghosting_full(gstPad, (sink is null) ? null : sink.getPadStruct(), flags) != 0;
1004 	}
1005 
1006 	/**
1007 	 * Mark a pad for needing reconfiguration. The next call to
1008 	 * gst_pad_check_reconfigure() will return %TRUE after this call.
1009 	 */
1010 	public void markReconfigure()
1011 	{
1012 		gst_pad_mark_reconfigure(gstPad);
1013 	}
1014 
1015 	/**
1016 	 * Check the #GST_PAD_FLAG_NEED_RECONFIGURE flag on @pad and return %TRUE
1017 	 * if the flag was set.
1018 	 *
1019 	 * Returns: %TRUE is the GST_PAD_FLAG_NEED_RECONFIGURE flag is set on @pad.
1020 	 */
1021 	public bool needsReconfigure()
1022 	{
1023 		return gst_pad_needs_reconfigure(gstPad) != 0;
1024 	}
1025 
1026 	/**
1027 	 * Pause the task of @pad. This function will also wait until the
1028 	 * function executed by the task is finished if this function is not
1029 	 * called from the task function.
1030 	 *
1031 	 * Returns: a %TRUE if the task could be paused or %FALSE when the pad
1032 	 *     has no task.
1033 	 */
1034 	public bool pauseTask()
1035 	{
1036 		return gst_pad_pause_task(gstPad) != 0;
1037 	}
1038 
1039 	/**
1040 	 * Performs gst_pad_query() on the peer of @pad.
1041 	 *
1042 	 * The caller is responsible for both the allocation and deallocation of
1043 	 * the query structure.
1044 	 *
1045 	 * Params:
1046 	 *     query = the #GstQuery to perform.
1047 	 *
1048 	 * Returns: %TRUE if the query could be performed. This function returns %FALSE
1049 	 *     if @pad has no peer.
1050 	 */
1051 	public bool peerQuery(Query query)
1052 	{
1053 		return gst_pad_peer_query(gstPad, (query is null) ? null : query.getQueryStruct()) != 0;
1054 	}
1055 
1056 	/**
1057 	 * Check if the peer of @pad accepts @caps. If @pad has no peer, this function
1058 	 * returns %TRUE.
1059 	 *
1060 	 * Params:
1061 	 *     caps = a #GstCaps to check on the pad
1062 	 *
1063 	 * Returns: %TRUE if the peer of @pad can accept the caps or @pad has no peer.
1064 	 */
1065 	public bool peerQueryAcceptCaps(Caps caps)
1066 	{
1067 		return gst_pad_peer_query_accept_caps(gstPad, (caps is null) ? null : caps.getCapsStruct()) != 0;
1068 	}
1069 
1070 	/**
1071 	 * Gets the capabilities of the peer connected to this pad. Similar to
1072 	 * gst_pad_query_caps().
1073 	 *
1074 	 * When called on srcpads @filter contains the caps that
1075 	 * upstream could produce in the order preferred by upstream. When
1076 	 * called on sinkpads @filter contains the caps accepted by
1077 	 * downstream in the preferred order. @filter might be %NULL but
1078 	 * if it is not %NULL the returned caps will be a subset of @filter.
1079 	 *
1080 	 * Params:
1081 	 *     filter = a #GstCaps filter, or %NULL.
1082 	 *
1083 	 * Returns: the caps of the peer pad with incremented
1084 	 *     ref-count. When there is no peer pad, this function returns @filter or,
1085 	 *     when @filter is %NULL, ANY caps.
1086 	 */
1087 	public Caps peerQueryCaps(Caps filter)
1088 	{
1089 		auto p = gst_pad_peer_query_caps(gstPad, (filter is null) ? null : filter.getCapsStruct());
1090 
1091 		if(p is null)
1092 		{
1093 			return null;
1094 		}
1095 
1096 		return ObjectG.getDObject!(Caps)(cast(GstCaps*) p, true);
1097 	}
1098 
1099 	/**
1100 	 * Queries the peer pad of a given sink pad to convert @src_val in @src_format
1101 	 * to @dest_format.
1102 	 *
1103 	 * Params:
1104 	 *     srcFormat = a #GstFormat to convert from.
1105 	 *     srcVal = a value to convert.
1106 	 *     destFormat = the #GstFormat to convert to.
1107 	 *     destVal = a pointer to the result.
1108 	 *
1109 	 * Returns: %TRUE if the query could be performed.
1110 	 */
1111 	public bool peerQueryConvert(GstFormat srcFormat, long srcVal, GstFormat destFormat, out long destVal)
1112 	{
1113 		return gst_pad_peer_query_convert(gstPad, srcFormat, srcVal, destFormat, &destVal) != 0;
1114 	}
1115 
1116 	/**
1117 	 * Queries the peer pad of a given sink pad for the total stream duration.
1118 	 *
1119 	 * Params:
1120 	 *     format = the #GstFormat requested
1121 	 *     duration = a location in which to store the total
1122 	 *         duration, or %NULL.
1123 	 *
1124 	 * Returns: %TRUE if the query could be performed.
1125 	 */
1126 	public bool peerQueryDuration(GstFormat format, out long duration)
1127 	{
1128 		return gst_pad_peer_query_duration(gstPad, format, &duration) != 0;
1129 	}
1130 
1131 	/**
1132 	 * Queries the peer of a given sink pad for the stream position.
1133 	 *
1134 	 * Params:
1135 	 *     format = the #GstFormat requested
1136 	 *     cur = a location in which to store the current
1137 	 *         position, or %NULL.
1138 	 *
1139 	 * Returns: %TRUE if the query could be performed.
1140 	 */
1141 	public bool peerQueryPosition(GstFormat format, out long cur)
1142 	{
1143 		return gst_pad_peer_query_position(gstPad, format, &cur) != 0;
1144 	}
1145 
1146 	/**
1147 	 * Checks if all internally linked pads of @pad accepts the caps in @query and
1148 	 * returns the intersection of the results.
1149 	 *
1150 	 * This function is useful as a default accept caps query function for an element
1151 	 * that can handle any stream format, but requires caps that are acceptable for
1152 	 * all opposite pads.
1153 	 *
1154 	 * Params:
1155 	 *     query = an ACCEPT_CAPS #GstQuery.
1156 	 *
1157 	 * Returns: %TRUE if @query could be executed
1158 	 */
1159 	public bool proxyQueryAcceptCaps(Query query)
1160 	{
1161 		return gst_pad_proxy_query_accept_caps(gstPad, (query is null) ? null : query.getQueryStruct()) != 0;
1162 	}
1163 
1164 	/**
1165 	 * Calls gst_pad_query_caps() for all internally linked pads of @pad and returns
1166 	 * the intersection of the results.
1167 	 *
1168 	 * This function is useful as a default caps query function for an element
1169 	 * that can handle any stream format, but requires all its pads to have
1170 	 * the same caps.  Two such elements are tee and adder.
1171 	 *
1172 	 * Params:
1173 	 *     query = a CAPS #GstQuery.
1174 	 *
1175 	 * Returns: %TRUE if @query could be executed
1176 	 */
1177 	public bool proxyQueryCaps(Query query)
1178 	{
1179 		return gst_pad_proxy_query_caps(gstPad, (query is null) ? null : query.getQueryStruct()) != 0;
1180 	}
1181 
1182 	/**
1183 	 * Pulls a @buffer from the peer pad or fills up a provided buffer.
1184 	 *
1185 	 * This function will first trigger the pad block signal if it was
1186 	 * installed.
1187 	 *
1188 	 * When @pad is not linked #GST_FLOW_NOT_LINKED is returned else this
1189 	 * function returns the result of gst_pad_get_range() on the peer pad.
1190 	 * See gst_pad_get_range() for a list of return values and for the
1191 	 * semantics of the arguments of this function.
1192 	 *
1193 	 * If @buffer points to a variable holding %NULL, a valid new #GstBuffer will be
1194 	 * placed in @buffer when this function returns #GST_FLOW_OK. The new buffer
1195 	 * must be freed with gst_buffer_unref() after usage. When this function
1196 	 * returns any other result value, @buffer will still point to %NULL.
1197 	 *
1198 	 * When @buffer points to a variable that points to a valid #GstBuffer, the
1199 	 * buffer will be filled with the result data when this function returns
1200 	 * #GST_FLOW_OK. When this function returns any other result value,
1201 	 * @buffer will be unchanged. If the provided buffer is larger than @size, only
1202 	 * @size bytes will be filled in the result buffer and its size will be updated
1203 	 * accordingly.
1204 	 *
1205 	 * Note that less than @size bytes can be returned in @buffer when, for example,
1206 	 * an EOS condition is near or when @buffer is not large enough to hold @size
1207 	 * bytes. The caller should check the result buffer size to get the result size.
1208 	 *
1209 	 * Params:
1210 	 *     offset = The start offset of the buffer
1211 	 *     size = The length of the buffer
1212 	 *     buffer = a pointer to hold the #GstBuffer, returns
1213 	 *         GST_FLOW_ERROR if %NULL.
1214 	 *
1215 	 * Returns: a #GstFlowReturn from the peer pad.
1216 	 *
1217 	 *     MT safe.
1218 	 */
1219 	public GstFlowReturn pullRange(ulong offset, uint size, out Buffer buffer)
1220 	{
1221 		GstBuffer* outbuffer = null;
1222 
1223 		auto p = gst_pad_pull_range(gstPad, offset, size, &outbuffer);
1224 
1225 		buffer = ObjectG.getDObject!(Buffer)(outbuffer);
1226 
1227 		return p;
1228 	}
1229 
1230 	/**
1231 	 * Pushes a buffer to the peer of @pad.
1232 	 *
1233 	 * This function will call installed block probes before triggering any
1234 	 * installed data probes.
1235 	 *
1236 	 * The function proceeds calling gst_pad_chain() on the peer pad and returns
1237 	 * the value from that function. If @pad has no peer, #GST_FLOW_NOT_LINKED will
1238 	 * be returned.
1239 	 *
1240 	 * In all cases, success or failure, the caller loses its reference to @buffer
1241 	 * after calling this function.
1242 	 *
1243 	 * Params:
1244 	 *     buffer = the #GstBuffer to push returns GST_FLOW_ERROR
1245 	 *         if not.
1246 	 *
1247 	 * Returns: a #GstFlowReturn from the peer pad.
1248 	 *
1249 	 *     MT safe.
1250 	 */
1251 	public GstFlowReturn push(Buffer buffer)
1252 	{
1253 		return gst_pad_push(gstPad, (buffer is null) ? null : buffer.getBufferStruct());
1254 	}
1255 
1256 	/**
1257 	 * Sends the event to the peer of the given pad. This function is
1258 	 * mainly used by elements to send events to their peer
1259 	 * elements.
1260 	 *
1261 	 * This function takes ownership of the provided event so you should
1262 	 * gst_event_ref() it if you want to reuse the event after this call.
1263 	 *
1264 	 * Params:
1265 	 *     event = the #GstEvent to send to the pad.
1266 	 *
1267 	 * Returns: %TRUE if the event was handled.
1268 	 *
1269 	 *     MT safe.
1270 	 */
1271 	public bool pushEvent(Event event)
1272 	{
1273 		return gst_pad_push_event(gstPad, (event is null) ? null : event.getEventStruct()) != 0;
1274 	}
1275 
1276 	/**
1277 	 * Pushes a buffer list to the peer of @pad.
1278 	 *
1279 	 * This function will call installed block probes before triggering any
1280 	 * installed data probes.
1281 	 *
1282 	 * The function proceeds calling the chain function on the peer pad and returns
1283 	 * the value from that function. If @pad has no peer, #GST_FLOW_NOT_LINKED will
1284 	 * be returned. If the peer pad does not have any installed chainlist function
1285 	 * every group buffer of the list will be merged into a normal #GstBuffer and
1286 	 * chained via gst_pad_chain().
1287 	 *
1288 	 * In all cases, success or failure, the caller loses its reference to @list
1289 	 * after calling this function.
1290 	 *
1291 	 * Params:
1292 	 *     list = the #GstBufferList to push returns GST_FLOW_ERROR
1293 	 *         if not.
1294 	 *
1295 	 * Returns: a #GstFlowReturn from the peer pad.
1296 	 *
1297 	 *     MT safe.
1298 	 */
1299 	public GstFlowReturn pushList(BufferList list)
1300 	{
1301 		return gst_pad_push_list(gstPad, (list is null) ? null : list.getBufferListStruct());
1302 	}
1303 
1304 	/**
1305 	 * Dispatches a query to a pad. The query should have been allocated by the
1306 	 * caller via one of the type-specific allocation functions. The element that
1307 	 * the pad belongs to is responsible for filling the query with an appropriate
1308 	 * response, which should then be parsed with a type-specific query parsing
1309 	 * function.
1310 	 *
1311 	 * Again, the caller is responsible for both the allocation and deallocation of
1312 	 * the query structure.
1313 	 *
1314 	 * Please also note that some queries might need a running pipeline to work.
1315 	 *
1316 	 * Params:
1317 	 *     query = the #GstQuery to perform.
1318 	 *
1319 	 * Returns: %TRUE if the query could be performed.
1320 	 */
1321 	public bool query(Query query)
1322 	{
1323 		return gst_pad_query(gstPad, (query is null) ? null : query.getQueryStruct()) != 0;
1324 	}
1325 
1326 	/**
1327 	 * Check if the given pad accepts the caps.
1328 	 *
1329 	 * Params:
1330 	 *     caps = a #GstCaps to check on the pad
1331 	 *
1332 	 * Returns: %TRUE if the pad can accept the caps.
1333 	 */
1334 	public bool queryAcceptCaps(Caps caps)
1335 	{
1336 		return gst_pad_query_accept_caps(gstPad, (caps is null) ? null : caps.getCapsStruct()) != 0;
1337 	}
1338 
1339 	/**
1340 	 * Gets the capabilities this pad can produce or consume.
1341 	 * Note that this method doesn't necessarily return the caps set by sending a
1342 	 * gst_event_new_caps() - use gst_pad_get_current_caps() for that instead.
1343 	 * gst_pad_query_caps returns all possible caps a pad can operate with, using
1344 	 * the pad's CAPS query function, If the query fails, this function will return
1345 	 * @filter, if not %NULL, otherwise ANY.
1346 	 *
1347 	 * When called on sinkpads @filter contains the caps that
1348 	 * upstream could produce in the order preferred by upstream. When
1349 	 * called on srcpads @filter contains the caps accepted by
1350 	 * downstream in the preferred order. @filter might be %NULL but
1351 	 * if it is not %NULL the returned caps will be a subset of @filter.
1352 	 *
1353 	 * Note that this function does not return writable #GstCaps, use
1354 	 * gst_caps_make_writable() before modifying the caps.
1355 	 *
1356 	 * Params:
1357 	 *     filter = suggested #GstCaps, or %NULL
1358 	 *
1359 	 * Returns: the caps of the pad with incremented ref-count.
1360 	 */
1361 	public Caps queryCaps(Caps filter)
1362 	{
1363 		auto p = gst_pad_query_caps(gstPad, (filter is null) ? null : filter.getCapsStruct());
1364 
1365 		if(p is null)
1366 		{
1367 			return null;
1368 		}
1369 
1370 		return ObjectG.getDObject!(Caps)(cast(GstCaps*) p, true);
1371 	}
1372 
1373 	/**
1374 	 * Queries a pad to convert @src_val in @src_format to @dest_format.
1375 	 *
1376 	 * Params:
1377 	 *     srcFormat = a #GstFormat to convert from.
1378 	 *     srcVal = a value to convert.
1379 	 *     destFormat = the #GstFormat to convert to.
1380 	 *     destVal = a pointer to the result.
1381 	 *
1382 	 * Returns: %TRUE if the query could be performed.
1383 	 */
1384 	public bool queryConvert(GstFormat srcFormat, long srcVal, GstFormat destFormat, out long destVal)
1385 	{
1386 		return gst_pad_query_convert(gstPad, srcFormat, srcVal, destFormat, &destVal) != 0;
1387 	}
1388 
1389 	/**
1390 	 * Invokes the default query handler for the given pad.
1391 	 * The query is sent to all pads internally linked to @pad. Note that
1392 	 * if there are many possible sink pads that are internally linked to
1393 	 * @pad, only one will be sent the query.
1394 	 * Multi-sinkpad elements should implement custom query handlers.
1395 	 *
1396 	 * Params:
1397 	 *     parent = the parent of @pad or %NULL
1398 	 *     query = the #GstQuery to handle.
1399 	 *
1400 	 * Returns: %TRUE if the query was performed successfully.
1401 	 */
1402 	public bool queryDefault(ObjectGst parent, Query query)
1403 	{
1404 		return gst_pad_query_default(gstPad, (parent is null) ? null : parent.getObjectGstStruct(), (query is null) ? null : query.getQueryStruct()) != 0;
1405 	}
1406 
1407 	/**
1408 	 * Queries a pad for the total stream duration.
1409 	 *
1410 	 * Params:
1411 	 *     format = the #GstFormat requested
1412 	 *     duration = a location in which to store the total
1413 	 *         duration, or %NULL.
1414 	 *
1415 	 * Returns: %TRUE if the query could be performed.
1416 	 */
1417 	public bool queryDuration(GstFormat format, out long duration)
1418 	{
1419 		return gst_pad_query_duration(gstPad, format, &duration) != 0;
1420 	}
1421 
1422 	/**
1423 	 * Queries a pad for the stream position.
1424 	 *
1425 	 * Params:
1426 	 *     format = the #GstFormat requested
1427 	 *     cur = A location in which to store the current position, or %NULL.
1428 	 *
1429 	 * Returns: %TRUE if the query could be performed.
1430 	 */
1431 	public bool queryPosition(GstFormat format, out long cur)
1432 	{
1433 		return gst_pad_query_position(gstPad, format, &cur) != 0;
1434 	}
1435 
1436 	/**
1437 	 * Remove the probe with @id from @pad.
1438 	 *
1439 	 * MT safe.
1440 	 *
1441 	 * Params:
1442 	 *     id = the probe id to remove
1443 	 */
1444 	public void removeProbe(gulong id)
1445 	{
1446 		gst_pad_remove_probe(gstPad, id);
1447 	}
1448 
1449 	/**
1450 	 * Sends the event to the pad. This function can be used
1451 	 * by applications to send events in the pipeline.
1452 	 *
1453 	 * If @pad is a source pad, @event should be an upstream event. If @pad is a
1454 	 * sink pad, @event should be a downstream event. For example, you would not
1455 	 * send a #GST_EVENT_EOS on a src pad; EOS events only propagate downstream.
1456 	 * Furthermore, some downstream events have to be serialized with data flow,
1457 	 * like EOS, while some can travel out-of-band, like #GST_EVENT_FLUSH_START. If
1458 	 * the event needs to be serialized with data flow, this function will take the
1459 	 * pad's stream lock while calling its event function.
1460 	 *
1461 	 * To find out whether an event type is upstream, downstream, or downstream and
1462 	 * serialized, see #GstEventTypeFlags, gst_event_type_get_flags(),
1463 	 * #GST_EVENT_IS_UPSTREAM, #GST_EVENT_IS_DOWNSTREAM, and
1464 	 * #GST_EVENT_IS_SERIALIZED. Note that in practice that an application or
1465 	 * plugin doesn't need to bother itself with this information; the core handles
1466 	 * all necessary locks and checks.
1467 	 *
1468 	 * This function takes ownership of the provided event so you should
1469 	 * gst_event_ref() it if you want to reuse the event after this call.
1470 	 *
1471 	 * Params:
1472 	 *     event = the #GstEvent to send to the pad.
1473 	 *
1474 	 * Returns: %TRUE if the event was handled.
1475 	 */
1476 	public bool sendEvent(Event event)
1477 	{
1478 		return gst_pad_send_event(gstPad, (event is null) ? null : event.getEventStruct()) != 0;
1479 	}
1480 
1481 	/**
1482 	 * Sets the given activate function for @pad. The activate function will
1483 	 * dispatch to gst_pad_activate_mode() to perform the actual activation.
1484 	 * Only makes sense to set on sink pads.
1485 	 *
1486 	 * Call this function if your sink pad can start a pull-based task.
1487 	 *
1488 	 * Params:
1489 	 *     activate = the #GstPadActivateFunction to set.
1490 	 *     userData = user_data passed to @notify
1491 	 *     notify = notify called when @activate will not be used anymore.
1492 	 */
1493 	public void setActivateFunctionFull(GstPadActivateFunction activate, void* userData, GDestroyNotify notify)
1494 	{
1495 		gst_pad_set_activate_function_full(gstPad, activate, userData, notify);
1496 	}
1497 
1498 	/**
1499 	 * Sets the given activate_mode function for the pad. An activate_mode function
1500 	 * prepares the element for data passing.
1501 	 *
1502 	 * Params:
1503 	 *     activatemode = the #GstPadActivateModeFunction to set.
1504 	 *     userData = user_data passed to @notify
1505 	 *     notify = notify called when @activatemode will not be used anymore.
1506 	 */
1507 	public void setActivatemodeFunctionFull(GstPadActivateModeFunction activatemode, void* userData, GDestroyNotify notify)
1508 	{
1509 		gst_pad_set_activatemode_function_full(gstPad, activatemode, userData, notify);
1510 	}
1511 
1512 	/**
1513 	 * Activates or deactivates the given pad.
1514 	 * Normally called from within core state change functions.
1515 	 *
1516 	 * If @active, makes sure the pad is active. If it is already active, either in
1517 	 * push or pull mode, just return. Otherwise dispatches to the pad's activate
1518 	 * function to perform the actual activation.
1519 	 *
1520 	 * If not @active, calls gst_pad_activate_mode() with the pad's current mode
1521 	 * and a %FALSE argument.
1522 	 *
1523 	 * Params:
1524 	 *     active = whether or not the pad should be active.
1525 	 *
1526 	 * Returns: %TRUE if the operation was successful.
1527 	 *
1528 	 *     MT safe.
1529 	 */
1530 	public bool setActive(bool active)
1531 	{
1532 		return gst_pad_set_active(gstPad, active) != 0;
1533 	}
1534 
1535 	/**
1536 	 * Sets the given chain function for the pad. The chain function is called to
1537 	 * process a #GstBuffer input buffer. see #GstPadChainFunction for more details.
1538 	 *
1539 	 * Params:
1540 	 *     chain = the #GstPadChainFunction to set.
1541 	 *     userData = user_data passed to @notify
1542 	 *     notify = notify called when @chain will not be used anymore.
1543 	 */
1544 	public void setChainFunctionFull(GstPadChainFunction chain, void* userData, GDestroyNotify notify)
1545 	{
1546 		gst_pad_set_chain_function_full(gstPad, chain, userData, notify);
1547 	}
1548 
1549 	/**
1550 	 * Sets the given chain list function for the pad. The chainlist function is
1551 	 * called to process a #GstBufferList input buffer list. See
1552 	 * #GstPadChainListFunction for more details.
1553 	 *
1554 	 * Params:
1555 	 *     chainlist = the #GstPadChainListFunction to set.
1556 	 *     userData = user_data passed to @notify
1557 	 *     notify = notify called when @chainlist will not be used anymore.
1558 	 */
1559 	public void setChainListFunctionFull(GstPadChainListFunction chainlist, void* userData, GDestroyNotify notify)
1560 	{
1561 		gst_pad_set_chain_list_function_full(gstPad, chainlist, userData, notify);
1562 	}
1563 
1564 	/**
1565 	 * Set the given private data gpointer on the pad.
1566 	 * This function can only be used by the element that owns the pad.
1567 	 * No locking is performed in this function.
1568 	 *
1569 	 * Params:
1570 	 *     priv = The private data to attach to the pad.
1571 	 */
1572 	public void setElementPrivate(void* priv)
1573 	{
1574 		gst_pad_set_element_private(gstPad, priv);
1575 	}
1576 
1577 	/**
1578 	 * Sets the given event handler for the pad.
1579 	 *
1580 	 * Params:
1581 	 *     event = the #GstPadEventFullFunction to set.
1582 	 *     userData = user_data passed to @notify
1583 	 *     notify = notify called when @event will not be used anymore.
1584 	 *
1585 	 * Since: 1.8
1586 	 */
1587 	public void setEventFullFunctionFull(GstPadEventFullFunction event, void* userData, GDestroyNotify notify)
1588 	{
1589 		gst_pad_set_event_full_function_full(gstPad, event, userData, notify);
1590 	}
1591 
1592 	/**
1593 	 * Sets the given event handler for the pad.
1594 	 *
1595 	 * Params:
1596 	 *     event = the #GstPadEventFunction to set.
1597 	 *     userData = user_data passed to @notify
1598 	 *     notify = notify called when @event will not be used anymore.
1599 	 */
1600 	public void setEventFunctionFull(GstPadEventFunction event, void* userData, GDestroyNotify notify)
1601 	{
1602 		gst_pad_set_event_function_full(gstPad, event, userData, notify);
1603 	}
1604 
1605 	/**
1606 	 * Sets the given getrange function for the pad. The getrange function is
1607 	 * called to produce a new #GstBuffer to start the processing pipeline. see
1608 	 * #GstPadGetRangeFunction for a description of the getrange function.
1609 	 *
1610 	 * Params:
1611 	 *     get = the #GstPadGetRangeFunction to set.
1612 	 *     userData = user_data passed to @notify
1613 	 *     notify = notify called when @get will not be used anymore.
1614 	 */
1615 	public void setGetrangeFunctionFull(GstPadGetRangeFunction get, void* userData, GDestroyNotify notify)
1616 	{
1617 		gst_pad_set_getrange_function_full(gstPad, get, userData, notify);
1618 	}
1619 
1620 	/**
1621 	 * Sets the given internal link iterator function for the pad.
1622 	 *
1623 	 * Params:
1624 	 *     iterintlink = the #GstPadIterIntLinkFunction to set.
1625 	 *     userData = user_data passed to @notify
1626 	 *     notify = notify called when @iterintlink will not be used anymore.
1627 	 */
1628 	public void setIterateInternalLinksFunctionFull(GstPadIterIntLinkFunction iterintlink, void* userData, GDestroyNotify notify)
1629 	{
1630 		gst_pad_set_iterate_internal_links_function_full(gstPad, iterintlink, userData, notify);
1631 	}
1632 
1633 	/**
1634 	 * Sets the given link function for the pad. It will be called when
1635 	 * the pad is linked with another pad.
1636 	 *
1637 	 * The return value #GST_PAD_LINK_OK should be used when the connection can be
1638 	 * made.
1639 	 *
1640 	 * The return value #GST_PAD_LINK_REFUSED should be used when the connection
1641 	 * cannot be made for some reason.
1642 	 *
1643 	 * If @link is installed on a source pad, it should call the #GstPadLinkFunction
1644 	 * of the peer sink pad, if present.
1645 	 *
1646 	 * Params:
1647 	 *     link = the #GstPadLinkFunction to set.
1648 	 *     userData = user_data passed to @notify
1649 	 *     notify = notify called when @link will not be used anymore.
1650 	 */
1651 	public void setLinkFunctionFull(GstPadLinkFunction link, void* userData, GDestroyNotify notify)
1652 	{
1653 		gst_pad_set_link_function_full(gstPad, link, userData, notify);
1654 	}
1655 
1656 	/**
1657 	 * Set the offset that will be applied to the running time of @pad.
1658 	 *
1659 	 * Params:
1660 	 *     offset = the offset
1661 	 */
1662 	public void setOffset(long offset)
1663 	{
1664 		gst_pad_set_offset(gstPad, offset);
1665 	}
1666 
1667 	/**
1668 	 * Set the given query function for the pad.
1669 	 *
1670 	 * Params:
1671 	 *     query = the #GstPadQueryFunction to set.
1672 	 *     userData = user_data passed to @notify
1673 	 *     notify = notify called when @query will not be used anymore.
1674 	 */
1675 	public void setQueryFunctionFull(GstPadQueryFunction query, void* userData, GDestroyNotify notify)
1676 	{
1677 		gst_pad_set_query_function_full(gstPad, query, userData, notify);
1678 	}
1679 
1680 	/**
1681 	 * Sets the given unlink function for the pad. It will be called
1682 	 * when the pad is unlinked.
1683 	 *
1684 	 * Params:
1685 	 *     unlink = the #GstPadUnlinkFunction to set.
1686 	 *     userData = user_data passed to @notify
1687 	 *     notify = notify called when @unlink will not be used anymore.
1688 	 */
1689 	public void setUnlinkFunctionFull(GstPadUnlinkFunction unlink, void* userData, GDestroyNotify notify)
1690 	{
1691 		gst_pad_set_unlink_function_full(gstPad, unlink, userData, notify);
1692 	}
1693 
1694 	/**
1695 	 * Starts a task that repeatedly calls @func with @user_data. This function
1696 	 * is mostly used in pad activation functions to start the dataflow.
1697 	 * The #GST_PAD_STREAM_LOCK of @pad will automatically be acquired
1698 	 * before @func is called.
1699 	 *
1700 	 * Params:
1701 	 *     func = the task function to call
1702 	 *     userData = user data passed to the task function
1703 	 *     notify = called when @user_data is no longer referenced
1704 	 *
1705 	 * Returns: a %TRUE if the task could be started.
1706 	 */
1707 	public bool startTask(GstTaskFunction func, void* userData, GDestroyNotify notify)
1708 	{
1709 		return gst_pad_start_task(gstPad, func, userData, notify) != 0;
1710 	}
1711 
1712 	/**
1713 	 * Iterates all sticky events on @pad and calls @foreach_func for every
1714 	 * event. If @foreach_func returns %FALSE the iteration is immediately stopped.
1715 	 *
1716 	 * Params:
1717 	 *     foreachFunc = the #GstPadStickyEventsForeachFunction that
1718 	 *         should be called for every event.
1719 	 *     userData = the optional user data.
1720 	 */
1721 	public void stickyEventsForeach(GstPadStickyEventsForeachFunction foreachFunc, void* userData)
1722 	{
1723 		gst_pad_sticky_events_foreach(gstPad, foreachFunc, userData);
1724 	}
1725 
1726 	/**
1727 	 * Stop the task of @pad. This function will also make sure that the
1728 	 * function executed by the task will effectively stop if not called
1729 	 * from the GstTaskFunction.
1730 	 *
1731 	 * This function will deadlock if called from the GstTaskFunction of
1732 	 * the task. Use gst_task_pause() instead.
1733 	 *
1734 	 * Regardless of whether the pad has a task, the stream lock is acquired and
1735 	 * released so as to ensure that streaming through this pad has finished.
1736 	 *
1737 	 * Returns: a %TRUE if the task could be stopped or %FALSE on error.
1738 	 */
1739 	public bool stopTask()
1740 	{
1741 		return gst_pad_stop_task(gstPad) != 0;
1742 	}
1743 
1744 	/**
1745 	 * Store the sticky @event on @pad
1746 	 *
1747 	 * Params:
1748 	 *     event = a #GstEvent
1749 	 *
1750 	 * Returns: #GST_FLOW_OK on success, #GST_FLOW_FLUSHING when the pad
1751 	 *     was flushing or #GST_FLOW_EOS when the pad was EOS.
1752 	 *
1753 	 * Since: 1.2
1754 	 */
1755 	public GstFlowReturn storeStickyEvent(Event event)
1756 	{
1757 		return gst_pad_store_sticky_event(gstPad, (event is null) ? null : event.getEventStruct());
1758 	}
1759 
1760 	/**
1761 	 * Unlinks the source pad from the sink pad. Will emit the #GstPad::unlinked
1762 	 * signal on both pads.
1763 	 *
1764 	 * Params:
1765 	 *     sinkpad = the sink #GstPad to unlink.
1766 	 *
1767 	 * Returns: %TRUE if the pads were unlinked. This function returns %FALSE if
1768 	 *     the pads were not linked together.
1769 	 *
1770 	 *     MT safe.
1771 	 */
1772 	public bool unlink(Pad sinkpad)
1773 	{
1774 		return gst_pad_unlink(gstPad, (sinkpad is null) ? null : sinkpad.getPadStruct()) != 0;
1775 	}
1776 
1777 	/**
1778 	 * A helper function you can use that sets the FIXED_CAPS flag
1779 	 * This way the default CAPS query will always return the negotiated caps
1780 	 * or in case the pad is not negotiated, the padtemplate caps.
1781 	 *
1782 	 * The negotiated caps are the caps of the last CAPS event that passed on the
1783 	 * pad. Use this function on a pad that, once it negotiated to a CAPS, cannot
1784 	 * be renegotiated to something else.
1785 	 */
1786 	public void useFixedCaps()
1787 	{
1788 		gst_pad_use_fixed_caps(gstPad);
1789 	}
1790 
1791 	/**
1792 	 * Signals that a pad has been linked to the peer pad.
1793 	 *
1794 	 * Params:
1795 	 *     peer = the peer pad that has been connected
1796 	 */
1797 	gulong addOnLinked(void delegate(Pad, Pad) dlg, ConnectFlags connectFlags=cast(ConnectFlags)0)
1798 	{
1799 		return Signals.connect(this, "linked", dlg, connectFlags ^ ConnectFlags.SWAPPED);
1800 	}
1801 
1802 	/**
1803 	 * Signals that a pad has been unlinked from the peer pad.
1804 	 *
1805 	 * Params:
1806 	 *     peer = the peer pad that has been disconnected
1807 	 */
1808 	gulong addOnUnlinked(void delegate(Pad, Pad) dlg, ConnectFlags connectFlags=cast(ConnectFlags)0)
1809 	{
1810 		return Signals.connect(this, "unlinked", dlg, connectFlags ^ ConnectFlags.SWAPPED);
1811 	}
1812 
1813 	/**
1814 	 * Gets a string representing the given flow return.
1815 	 *
1816 	 * Params:
1817 	 *     ret = a #GstFlowReturn to get the name of.
1818 	 *
1819 	 * Returns: a static string with the name of the flow return.
1820 	 */
1821 	public static string flowGetName(GstFlowReturn ret)
1822 	{
1823 		return Str.toString(gst_flow_get_name(ret));
1824 	}
1825 
1826 	/**
1827 	 * Get the unique quark for the given GstFlowReturn.
1828 	 *
1829 	 * Params:
1830 	 *     ret = a #GstFlowReturn to get the quark of.
1831 	 *
1832 	 * Returns: the quark associated with the flow return or 0 if an
1833 	 *     invalid return was specified.
1834 	 */
1835 	public static GQuark flowToQuark(GstFlowReturn ret)
1836 	{
1837 		return gst_flow_to_quark(ret);
1838 	}
1839 
1840 	/**
1841 	 * Return the name of a pad mode, for use in debug messages mostly.
1842 	 *
1843 	 * Params:
1844 	 *     mode = the pad mode
1845 	 *
1846 	 * Returns: short mnemonic for pad mode @mode
1847 	 */
1848 	public static string modeGetName(GstPadMode mode)
1849 	{
1850 		return Str.toString(gst_pad_mode_get_name(mode));
1851 	}
1852 }