/* GStreamer

 * Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>

 *               2000,2004 Wim Taymans <wim@fluendo.com>

 *

 * gstelement.h: Header for GstElement

 *

 * This library is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Library General Public

 * License as published by the Free Software Foundation; either

 * version 2 of the License, or (at your option) any later version.

 *

 * This library is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

 * Library General Public License for more details.

 *

 * You should have received a copy of the GNU Library General Public

 * License along with this library; if not, write to the

 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,

 * Boston, MA 02111-1307, USA.

 */

#ifndef __GST_ELEMENT_H__

#define __GST_ELEMENT_H__

/* gstelement.h and gstelementfactory.h include eachother */

typedef struct _GstElement GstElement;

typedef struct _GstElementClass GstElementClass;

/* gstmessage.h needs State */

/**

 * GstState:

 * @GST_STATE_VOID_PENDING     : no pending state.

 * @GST_STATE_NULL             : the NULL state or initial state of an element

 * @GST_STATE_READY            : the element is ready to go to PAUSED

 * @GST_STATE_PAUSED           : the element is PAUSED

 * @GST_STATE_PLAYING          : the element is PLAYING

 *

 * The posible states an element can be in.

 */

typedef enum {

  GST_STATE_VOID_PENDING        = 0,

  GST_STATE_NULL                = 1,

  GST_STATE_READY               = 2,

  GST_STATE_PAUSED              = 3,

  GST_STATE_PLAYING             = 4

} GstState;

#include <gst/gstconfig.h>

#include <gst/gstobject.h>

#include <gst/gstpad.h>

#include <gst/gstbus.h>

#include <gst/gstclock.h>

#include <gst/gstelementfactory.h>

#include <gst/gstplugin.h>

#include <gst/gstpluginfeature.h>

#include <gst/gstindex.h>

#include <gst/gstindexfactory.h>

#include <gst/gstiterator.h>

#include <gst/gstmessage.h>

#include <gst/gsttaglist.h>

G_BEGIN_DECLS

#define GST_TYPE_ELEMENT		(gst_element_get_type ())

#define GST_IS_ELEMENT(obj)		(G_TYPE_CHECK_INSTANCE_TYPE ((obj), GST_TYPE_ELEMENT))

#define GST_IS_ELEMENT_CLASS(klass)	(G_TYPE_CHECK_CLASS_TYPE ((klass), GST_TYPE_ELEMENT))

#define GST_ELEMENT_GET_CLASS(obj)	(G_TYPE_INSTANCE_GET_CLASS ((obj), GST_TYPE_ELEMENT, GstElementClass))

#define GST_ELEMENT(obj)		(G_TYPE_CHECK_INSTANCE_CAST ((obj), GST_TYPE_ELEMENT, GstElement))

#define GST_ELEMENT_CLASS(klass)	(G_TYPE_CHECK_CLASS_CAST ((klass), GST_TYPE_ELEMENT, GstElementClass))

#define GST_ELEMENT_CAST(obj)		((GstElement*)(obj))

/**

 * GstStateChangeReturn:

 * @GST_STATE_CHANGE_FAILURE   : the state change failed

 * @GST_STATE_CHANGE_SUCCESS   : the state change succeeded

 * @GST_STATE_CHANGE_ASYNC     : the state change will happen asynchronously

 * @GST_STATE_CHANGE_NO_PREROLL: the state change succeeded but the element

 *                               cannot produce data in PAUSED. This typically

 *                               happens with live sources.

 *

 * The possible return values from a state change function. Only

 * @GST_STATE_CHANGE_FAILURE is a real failure.

 */

typedef enum {

  GST_STATE_CHANGE_FAILURE             = 0,

  GST_STATE_CHANGE_SUCCESS             = 1,

  GST_STATE_CHANGE_ASYNC               = 2,

  GST_STATE_CHANGE_NO_PREROLL          = 3

} GstStateChangeReturn;

/* NOTE: this probably should be done with an #ifdef to decide

 * whether to safe-cast or to just do the non-checking cast.

 */

/**

 * GST_STATE:

 * @elem: a #GstElement to return state for.

 *

 * This macro returns the current #GstState of the element.

 */

#define GST_STATE(elem)			(GST_ELEMENT_CAST(elem)->current_state)

/**

 * GST_STATE_NEXT:

 * @elem: a #GstElement to return the next state for.

 *

 * This macro returns the next #GstState of the element.

 */

#define GST_STATE_NEXT(elem)		(GST_ELEMENT_CAST(elem)->next_state)

/**

 * GST_STATE_PENDING:

 * @elem: a #GstElement to return the pending state for.

 *

 * This macro returns the currently pending #GstState of the element.

 */

#define GST_STATE_PENDING(elem)		(GST_ELEMENT_CAST(elem)->pending_state)

/**

 * GST_STATE_TARGET:

 * @elem: a #GstElement to return the target state for.

 *

 * This macro returns the target #GstState of the element.

 *

 * Since: 0.10.13

 */

#define GST_STATE_TARGET(elem)		(GST_ELEMENT_CAST(elem)->abidata.ABI.target_state)

/**

 * GST_STATE_RETURN:

 * @elem: a #GstElement to return the last state result for.

 *

 * This macro returns the last #GstStateChangeReturn value.

 */

#define GST_STATE_RETURN(elem)		(GST_ELEMENT_CAST(elem)->last_return)

#define __GST_SIGN(val)			((val) < 0 ? -1 : ((val) > 0 ? 1 : 0))

/**

 * GST_STATE_GET_NEXT:

 * @cur: A starting #GstState

 * @pending: A target #GstState

 *

 * Given a current state @cur and a target state @pending, calculate the next (intermediate)

 * #GstState.

 */

#define GST_STATE_GET_NEXT(cur,pending)		((cur) + __GST_SIGN ((gint)(pending) - (gint)(cur)))

/**

 * GST_STATE_TRANSITION:

 * @cur: A current state

 * @next: A next state

 *

 * Given a current state @cur and a next state @next, calculate the associated

 * #GstStateChange transition.

 */

#define GST_STATE_TRANSITION(cur,next)		((GstStateChange)(((cur)<<3)|(next)))

/**

 * GST_STATE_TRANSITION_CURRENT:

 * @trans: A #GstStateChange

 *

 * Given a state transition @trans, extract the current #GstState.

 */

#define GST_STATE_TRANSITION_CURRENT(trans)	((GstState)((trans)>>3))

/**

 * GST_STATE_TRANSITION_NEXT:

 * @trans: A #GstStateChange

 *

 * Given a state transition @trans, extract the next #GstState.

 */

#define GST_STATE_TRANSITION_NEXT(trans)	((GstState)((trans)&0x7))

/**

 * GstStateChange:

 * @GST_STATE_CHANGE_NULL_TO_READY    : state change from NULL to READY

 * @GST_STATE_CHANGE_READY_TO_PAUSED  : state change from READY to PAUSED

 * @GST_STATE_CHANGE_PAUSED_TO_PLAYING: state change from PAUSED to PLAYING

 * @GST_STATE_CHANGE_PLAYING_TO_PAUSED: state change from PLAYING to PAUSED

 * @GST_STATE_CHANGE_PAUSED_TO_READY  : state change from PAUSED to READY

 * @GST_STATE_CHANGE_READY_TO_NULL    : state change from READY to NULL

 *

 * The different (interesting) state changes that are passed to the

 * state change functions of elements.

 */

typedef enum /*< flags=0 >*/

{

  GST_STATE_CHANGE_NULL_TO_READY	= (GST_STATE_NULL<<3) | GST_STATE_READY,

  GST_STATE_CHANGE_READY_TO_PAUSED	= (GST_STATE_READY<<3) | GST_STATE_PAUSED,

  GST_STATE_CHANGE_PAUSED_TO_PLAYING	= (GST_STATE_PAUSED<<3) | GST_STATE_PLAYING,

  GST_STATE_CHANGE_PLAYING_TO_PAUSED	= (GST_STATE_PLAYING<<3) | GST_STATE_PAUSED,

  GST_STATE_CHANGE_PAUSED_TO_READY	= (GST_STATE_PAUSED<<3) | GST_STATE_READY,

  GST_STATE_CHANGE_READY_TO_NULL	= (GST_STATE_READY<<3) | GST_STATE_NULL

} GstStateChange;

/**

 * GstElementFlags:

 * @GST_ELEMENT_LOCKED_STATE: ignore state changes from parent

 * @GST_ELEMENT_IS_SINK: the element is a sink

 * @GST_ELEMENT_UNPARENTING: Child is being removed from the parent bin.

 *  gst_bin_remove() on a child already being removed immediately returns FALSE

 * @GST_ELEMENT_FLAG_LAST: offset to define more flags

 *

 * The standard flags that an element may have.

 */

typedef enum

{

  GST_ELEMENT_LOCKED_STATE      = (GST_OBJECT_FLAG_LAST << 0),

  GST_ELEMENT_IS_SINK           = (GST_OBJECT_FLAG_LAST << 1),

  GST_ELEMENT_UNPARENTING       = (GST_OBJECT_FLAG_LAST << 2),

  /* padding */

  GST_ELEMENT_FLAG_LAST         = (GST_OBJECT_FLAG_LAST << 16)

} GstElementFlags;

/**

 * GST_ELEMENT_IS_LOCKED_STATE:

 * @elem: A #GstElement to query

 *

 * Check if the element is in the locked state and therefore will ignore state

 * changes from its parent object.

 */

#define GST_ELEMENT_IS_LOCKED_STATE(elem)        (GST_OBJECT_FLAG_IS_SET(elem,GST_ELEMENT_LOCKED_STATE))

/**

 * GST_ELEMENT_NAME:

 * @elem: A #GstElement to query

 *

 * Gets the name of this element. Use only in core as this is not

 * ABI-compatible. Others use gst_element_get_name()

 */

#define GST_ELEMENT_NAME(elem)			(GST_OBJECT_NAME(elem))

/**

 * GST_ELEMENT_PARENT:

 * @elem: A #GstElement to query

 *

 * Get the parent object of this element.

 */

#define GST_ELEMENT_PARENT(elem)		(GST_ELEMENT_CAST(GST_OBJECT_PARENT(elem)))

/**

 * GST_ELEMENT_BUS:

 * @elem: A #GstElement to query

 *

 * Get the message bus of this element.

 */

#define GST_ELEMENT_BUS(elem)			(GST_ELEMENT_CAST(elem)->bus)

/**

 * GST_ELEMENT_CLOCK:

 * @elem: A #GstElement to query

 *

 * Get the clock of this element

 */

#define GST_ELEMENT_CLOCK(elem)			(GST_ELEMENT_CAST(elem)->clock)

/**

 * GST_ELEMENT_PADS:

 * @elem: A #GstElement to query

 *

 * Get the pads of this elements.

 */

#define GST_ELEMENT_PADS(elem)			(GST_ELEMENT_CAST(elem)->pads)

/**

 * GST_ELEMENT_ERROR:

 * @el:     the element that generates the error

 * @text:   the message to display (format string and args enclosed in

            parentheses)

 * @debug:  debugging information for the message (format string and args

            enclosed in parentheses)

 *

 * Utility function that elements can use in case they encountered a fatal

 * data processing error. The pipeline will post an error message and the

 * application will be requested to stop further media processing.

 */

#define GST_ELEMENT_ERROR(el, domain, code, text, debug)		\

G_STMT_START {								\

  gchar *__txt = _gst_element_error_printf text;			\

  gchar *__dbg = _gst_element_error_printf debug;			\

  if (__txt)								\

    GST_WARNING_OBJECT (el, "error: %s", __txt);			\

  if (__dbg)								\

    GST_WARNING_OBJECT (el, "error: %s", __dbg);			\

  gst_element_message_full (GST_ELEMENT(el), GST_MESSAGE_ERROR,		\

    GST_ ## domain ## _ERROR, GST_ ## domain ## _ERROR_ ## code,	\

    __txt, __dbg, __FILE__, GST_FUNCTION, __LINE__);			\

} G_STMT_END

/**

 * GST_ELEMENT_WARNING:

 * @el:     the element that generates the warning

 * @domain: like CORE, LIBRARY, RESOURCE or STREAM (see #gstreamer-GstGError)

 * @code:   error code defined for that domain (see #gstreamer-GstGError)

 * @text:   the message to display (format string and args enclosed in

            parentheses)

 * @debug:  debugging information for the message (format string and args

            enclosed in parentheses)

 *

 * Utility function that elements can use in case they encountered a non-fatal

 * data processing problem. The pipeline will post a warning message and the

 * application will be informed.

 */

#define GST_ELEMENT_WARNING(el, domain, code, text, debug)		\

G_STMT_START {								\

  gchar *__txt = _gst_element_error_printf text;			\

  gchar *__dbg = _gst_element_error_printf debug;			\

  if (__txt)								\

    GST_WARNING_OBJECT (el, "warning: %s", __txt);			\

  if (__dbg)								\

    GST_WARNING_OBJECT (el, "warning: %s", __dbg);			\

  gst_element_message_full (GST_ELEMENT(el), GST_MESSAGE_WARNING,	\

    GST_ ## domain ## _ERROR, GST_ ## domain ## _ERROR_ ## code,	\

  __txt, __dbg, __FILE__, GST_FUNCTION, __LINE__);			\

} G_STMT_END

/**

 * GST_ELEMENT_INFO:

 * @el:     the element that generates the information

 * @domain: like CORE, LIBRARY, RESOURCE or STREAM (see #gstreamer-GstGError)

 * @code:   error code defined for that domain (see #gstreamer-GstGError)

 * @text:   the message to display (format string and args enclosed in

            parentheses)

 * @debug:  debugging information for the message (format string and args

            enclosed in parentheses)

 *

 * Utility function that elements can use in case they want to inform

 * the application of something noteworthy that is not an error.

 * The pipeline will post a warning message and the

 * application will be informed.

 *

 * Since: 0.10.12

 */

#define GST_ELEMENT_INFO(el, domain, code, text, debug)			\

G_STMT_START {								\

  gchar *__txt = _gst_element_error_printf text;			\

  gchar *__dbg = _gst_element_error_printf debug;			\

  if (__txt)								\

    GST_INFO_OBJECT (el, "info: %s", __txt);				\

  if (__dbg)								\

    GST_INFO_OBJECT (el, "info: %s", __dbg);				\

  gst_element_message_full (GST_ELEMENT(el), GST_MESSAGE_INFO,		\

    GST_ ## domain ## _ERROR, GST_ ## domain ## _ERROR_ ## code,	\

  __txt, __dbg, __FILE__, GST_FUNCTION, __LINE__);			\

} G_STMT_END

/* the state change mutexes and conds */

/**

 * GST_STATE_GET_LOCK:

 * @elem:   a #GstElement

 *

 * Get a reference to the state lock of @elem.

 * This lock is used by the core.  It is taken while getting or setting

 * the state, during state changes, and while finalizing.

 */

#define GST_STATE_GET_LOCK(elem)               (GST_ELEMENT_CAST(elem)->state_lock)

/**

 * GST_STATE_GET_COND:

 * @elem: a #GstElement

 *

 * Get the conditional used to signal the completion of a state change.

 */

#define GST_STATE_GET_COND(elem)               (GST_ELEMENT_CAST(elem)->state_cond)

#define GST_STATE_LOCK(elem)                   g_static_rec_mutex_lock(GST_STATE_GET_LOCK(elem))

#define GST_STATE_TRYLOCK(elem)                g_static_rec_mutex_trylock(GST_STATE_GET_LOCK(elem))

#define GST_STATE_UNLOCK(elem)                 g_static_rec_mutex_unlock(GST_STATE_GET_LOCK(elem))

#define GST_STATE_UNLOCK_FULL(elem)            g_static_rec_mutex_unlock_full(GST_STATE_GET_LOCK(elem))

#define GST_STATE_LOCK_FULL(elem,t)            g_static_rec_mutex_lock_full(GST_STATE_GET_LOCK(elem), t)

#define GST_STATE_WAIT(elem)                   g_cond_wait (GST_STATE_GET_COND (elem), \

							GST_OBJECT_GET_LOCK (elem))

#define GST_STATE_TIMED_WAIT(elem, timeval)    g_cond_timed_wait (GST_STATE_GET_COND (elem), \

							GST_OBJECT_GET_LOCK (elem), timeval)

#define GST_STATE_SIGNAL(elem)                 g_cond_signal (GST_STATE_GET_COND (elem));

#define GST_STATE_BROADCAST(elem)              g_cond_broadcast (GST_STATE_GET_COND (elem));

/**

 * GstElement:

 * @state_lock: Used to serialize execution of gst_element_set_state()

 * @state_cond: Used to signal completion of a state change

 * @state_cookie: Used to detect concurrent execution of

 * gst_element_set_state() and gst_element_get_state()

 * @current_state: the current state of an element

 * @next_state: the next state of an element, can be #GST_STATE_VOID_PENDING if

 * the element is in the correct state.

 * @pending_state: the final state the element should go to, can be

 * #GST_STATE_VOID_PENDING if the element is in the correct state

 * @last_return: the last return value of an element state change

 * @bus: the bus of the element. This bus is provided to the element by the

 * parent element or the application. A #GstPipeline has a bus of its own.

 * @clock: the clock of the element. This clock is usually provided by to the

 * element by the toplevel #GstPipeline.

 * @base_time: the time of the clock right before the element is set to

 * PLAYING. Subtracting @base_time from the current clock time in the PLAYING

 * @numpads: number of pads of the element, includes both source and sink pads.

 * @pads: list of pads

 * @numsrcpads: number of source pads of the element.

 * @srcpads: list of source pads

 * @numsinkpads: number of sink pads of the element.

 * @sinkpads: list of sink pads

 * @pads_cookie: updated whenever the a pad is added or removed

 *

 * GStreamer element abstract base class.

 */

struct _GstElement

{

  GstObject		object;

  /*< public >*/ /* with LOCK */

  GStaticRecMutex      *state_lock;

  /* element state */

  GCond                *state_cond;

  guint32		state_cookie;

  GstState              current_state;

  GstState              next_state;

  GstState              pending_state;

  GstStateChangeReturn  last_return;

  GstBus	       *bus;

  /* allocated clock */

  GstClock	       *clock;

  GstClockTimeDiff	base_time; /* NULL/READY: 0 - PAUSED: current time - PLAYING: difference to clock */

  /* element pads, these lists can only be iterated while holding

   * the LOCK or checking the cookie after each LOCK. */

  guint16               numpads;

  GList                *pads;

  guint16               numsrcpads;

  GList                *srcpads;

  guint16               numsinkpads;

  GList                *sinkpads;

  guint32               pads_cookie;

  /*< private >*/

  union {

    struct {

      /* state set by application */

      GstState              target_state;

    } ABI;

    /* adding + 0 to mark ABI change to be undone later */

    gpointer _gst_reserved[GST_PADDING + 0];

  } abidata;

};

/**

 * GstElementClass:

 * @parent_class: the parent class structure

 * @details: #GstElementDetails for elements of this class

 * @elementfactory: the #GstElementFactory that creates these elements

 * @padtemplates: a #GList of #GstPadTemplate

 * @numpadtemplates: the number of padtemplates

 * @pad_templ_cookie: changed whenever the padtemplates change

 * @request_new_pad: called when a new pad is requested

 * @release_pad: called when a request pad is to be released

 * @get_state: get the state of the element

 * @set_state: set a new state on the element

 * @change_state: called by @set_state to perform an incremental state change

 * @set_bus: set a #GstBus on the element

 * @provide_clock: gets the #GstClock provided by the element

 * @set_clock: set the #GstClock on the element

 * @get_index: set a #GstIndex on the element

 * @set_index: get the #GstIndex of an element

 * @send_event: send a #GstEvent to the element

 * @get_query_types: get the supported #GstQueryType of this element

 * @query: perform a #GstQuery on the element

 *

 * GStreamer element class. Override the vmethods to implement the element

 * functionality.

 */

struct _GstElementClass

{

  GstObjectClass         parent_class;

  /*< public >*/

  /* the element details */

  GstElementDetails	 details;

  /* factory that the element was created from */

  GstElementFactory	*elementfactory;

  /* templates for our pads */

  GList                 *padtemplates;

  gint                   numpadtemplates;

  guint32                pad_templ_cookie;

  /*< private >*/

  /* signal callbacks */

  void (*pad_added)	(GstElement *element, GstPad *pad);

  void (*pad_removed)	(GstElement *element, GstPad *pad);

  void (*no_more_pads)	(GstElement *element);

  /*< public >*/

  /* virtual methods for subclasses */

  /* request/release pads */

  GstPad*		(*request_new_pad)	(GstElement *element, GstPadTemplate *templ, const gchar* name);

  void			(*release_pad)		(GstElement *element, GstPad *pad);

  /* state changes */

  GstStateChangeReturn (*get_state)		(GstElement * element, GstState * state,

						 GstState * pending, GstClockTime timeout);

  GstStateChangeReturn (*set_state)		(GstElement *element, GstState state);

  GstStateChangeReturn (*change_state)		(GstElement *element, GstStateChange transition);

  /* bus */

  void			(*set_bus)		(GstElement * element, GstBus * bus);

  /* set/get clocks */

  GstClock*		(*provide_clock)	(GstElement *element);

  gboolean		(*set_clock)		(GstElement *element, GstClock *clock);

  /* index */

  GstIndex*		(*get_index)		(GstElement *element);

  void			(*set_index)		(GstElement *element, GstIndex *index);

  /* query functions */

  gboolean		(*send_event)		(GstElement *element, GstEvent *event);

  const GstQueryType*	(*get_query_types)	(GstElement *element);

  gboolean		(*query)		(GstElement *element, GstQuery *query);

  /*< private >*/

  gpointer _gst_reserved[GST_PADDING];