gstreamer/gst/gstpad.h

1041 lines
38 KiB
C

/* GStreamer
* Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
* 2000 Wim Taymans <wim.taymans@chello.be>
*
* gstpad.h: Header for GstPad object
*
* 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_PAD_H__
#define __GST_PAD_H__
#include <gst/gstconfig.h>
#include <gst/gstobject.h>
#include <gst/gstbuffer.h>
#include <gst/gstbufferlist.h>
#include <gst/gstcaps.h>
#include <gst/gstevent.h>
#include <gst/gstquery.h>
#include <gst/gsttask.h>
G_BEGIN_DECLS
/*
* Pad base class
*/
#define GST_TYPE_PAD (gst_pad_get_type ())
#define GST_IS_PAD(obj) (G_TYPE_CHECK_INSTANCE_TYPE ((obj), GST_TYPE_PAD))
#define GST_IS_PAD_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE ((klass), GST_TYPE_PAD))
#define GST_PAD(obj) (G_TYPE_CHECK_INSTANCE_CAST ((obj), GST_TYPE_PAD, GstPad))
#define GST_PAD_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST ((klass), GST_TYPE_PAD, GstPadClass))
#define GST_PAD_CAST(obj) ((GstPad*)(obj))
typedef struct _GstPad GstPad;
typedef struct _GstPadPrivate GstPadPrivate;
typedef struct _GstPadClass GstPadClass;
/**
* GstPadLinkReturn:
* @GST_PAD_LINK_OK : link succeeded
* @GST_PAD_LINK_WRONG_HIERARCHY: pads have no common grandparent
* @GST_PAD_LINK_WAS_LINKED : pad was already linked
* @GST_PAD_LINK_WRONG_DIRECTION: pads have wrong direction
* @GST_PAD_LINK_NOFORMAT : pads do not have common format
* @GST_PAD_LINK_NOSCHED : pads cannot cooperate in scheduling
* @GST_PAD_LINK_REFUSED : refused for some reason
*
* Result values from gst_pad_link and friends.
*/
typedef enum {
GST_PAD_LINK_OK = 0,
GST_PAD_LINK_WRONG_HIERARCHY = -1,
GST_PAD_LINK_WAS_LINKED = -2,
GST_PAD_LINK_WRONG_DIRECTION = -3,
GST_PAD_LINK_NOFORMAT = -4,
GST_PAD_LINK_NOSCHED = -5,
GST_PAD_LINK_REFUSED = -6
} GstPadLinkReturn;
/**
* GST_PAD_LINK_FAILED:
* @ret: the #GstPadLinkReturn value
*
* Macro to test if the given #GstPadLinkReturn value indicates a failed
* link step.
*/
#define GST_PAD_LINK_FAILED(ret) ((ret) < GST_PAD_LINK_OK)
/**
* GST_PAD_LINK_SUCCESSFUL:
* @ret: the #GstPadLinkReturn value
*
* Macro to test if the given #GstPadLinkReturn value indicates a successful
* link step.
*/
#define GST_PAD_LINK_SUCCESSFUL(ret) ((ret) >= GST_PAD_LINK_OK)
/**
* GstFlowReturn:
* @GST_FLOW_RESEND: Resend buffer, possibly with new caps (not
* sent yet) (unused/unimplemented).
* @GST_FLOW_OK: Data passing was ok.
* @GST_FLOW_NOT_LINKED: Pad is not linked.
* @GST_FLOW_WRONG_STATE: Pad is in wrong state.
* @GST_FLOW_UNEXPECTED: Did not expect anything, like after EOS.
* @GST_FLOW_NOT_NEGOTIATED: Pad is not negotiated.
* @GST_FLOW_ERROR: Some (fatal) error occured. Element generating
* this error should post an error message with more
* details.
* @GST_FLOW_NOT_SUPPORTED: This operation is not supported.
* @GST_FLOW_CUSTOM_SUCCESS: Elements can use values starting from
* this (and higher) to define custom success
* codes. Since 0.10.7.
* @GST_FLOW_CUSTOM_SUCCESS_1: Pre-defined custom success code (define your
* custom success code to this to avoid compiler
* warnings). Since 0.10.29.
* @GST_FLOW_CUSTOM_SUCCESS_2: Pre-defined custom success code. Since 0.10.29.
* @GST_FLOW_CUSTOM_ERROR: Elements can use values starting from
* this (and lower) to define custom error codes.
* Since 0.10.7.
* @GST_FLOW_CUSTOM_ERROR_1: Pre-defined custom error code (define your
* custom error code to this to avoid compiler
* warnings). Since 0.10.29.
* @GST_FLOW_CUSTOM_ERROR_2: Pre-defined custom error code. Since 0.10.29.
*
* The result of passing data to a pad.
*
* Note that the custom return values should not be exposed outside of the
* element scope and are available since 0.10.7.
*/
/* FIXME 0.11: remove custom flow returns */
typedef enum {
/* custom success starts here */
GST_FLOW_CUSTOM_SUCCESS_2 = 102,
GST_FLOW_CUSTOM_SUCCESS_1 = 101,
GST_FLOW_CUSTOM_SUCCESS = 100,
/* core predefined */
GST_FLOW_RESEND = 1,
GST_FLOW_OK = 0,
/* expected failures */
GST_FLOW_NOT_LINKED = -1,
GST_FLOW_WRONG_STATE = -2,
/* error cases */
GST_FLOW_UNEXPECTED = -3,
GST_FLOW_NOT_NEGOTIATED = -4,
GST_FLOW_ERROR = -5,
GST_FLOW_NOT_SUPPORTED = -6,
/* custom error starts here */
GST_FLOW_CUSTOM_ERROR = -100,
GST_FLOW_CUSTOM_ERROR_1 = -101,
GST_FLOW_CUSTOM_ERROR_2 = -102
} GstFlowReturn;
/**
* GST_FLOW_IS_FATAL:
* @ret: a #GstFlowReturn value
*
* Macro to test if the given #GstFlowReturn value indicates a fatal
* error. This macro is mainly used in elements driving the pipeline to decide
* whether an error message should be posted on the bus. Note that such
* elements may also need to post an error message in the #GST_FLOW_NOT_LINKED
* case which is not caught by this macro.
*
* Deprecated: This macro is badly named and can't be used in any real
* scenarios without additional checks.
*/
#ifndef GST_DISABLE_DEPRECATED
#define GST_FLOW_IS_FATAL(ret) ((ret) <= GST_FLOW_UNEXPECTED)
#endif
/**
* GST_FLOW_IS_SUCCESS:
* @ret: a #GstFlowReturn value
*
* Macro to test if the given #GstFlowReturn value indicates a
* successful result
* This macro is mainly used in elements to decide if the processing
* of a buffer was successful.
*
* Since: 0.10.7
*
* Deprecated: This macro is badly named and can't be used in any real
* scenarios without additional checks.
*/
#ifndef GST_DISABLE_DEPRECATED
#define GST_FLOW_IS_SUCCESS(ret) ((ret) >= GST_FLOW_OK)
#endif
const gchar* gst_flow_get_name (GstFlowReturn ret);
GQuark gst_flow_to_quark (GstFlowReturn ret);
/**
* GstPadLinkCheck:
* @GST_PAD_LINK_CHECK_NOTHING: Don't check hierarchy or caps compatibility.
* @GST_PAD_LINK_CHECK_HIERARCHY: Check the pads have same parents/grandparents.
* Could be omitted if it is already known that the two elements that own the
* pads are in the same bin.
* @GST_PAD_LINK_CHECK_TEMPLATE_CAPS: Check if the pads are compatible by using
* their template caps. This is much faster than @GST_PAD_LINK_CHECK_CAPS, but
* would be unsafe e.g. if one pad has %GST_CAPS_ANY.
* @GST_PAD_LINK_CHECK_CAPS: Check if the pads are compatible by comparing the
* caps returned by gst_pad_get_caps().
*
* The amount of checking to be done when linking pads. @GST_PAD_LINK_CHECK_CAPS
* and @GST_PAD_LINK_CHECK_TEMPLATE_CAPS are mutually exclusive. If both are
* specified, expensive but safe @GST_PAD_LINK_CHECK_CAPS are performed.
*
* <warning><para>
* Only disable some of the checks if you are 100% certain you know the link
* will not fail because of hierarchy/caps compatibility failures. If uncertain,
* use the default checks (%GST_PAD_LINK_CHECK_DEFAULT) or the regular methods
* for linking the pads.
* </para></warning>
*
* Since: 0.10.30
*/
typedef enum {
GST_PAD_LINK_CHECK_NOTHING = 0,
GST_PAD_LINK_CHECK_HIERARCHY = 1 << 0,
GST_PAD_LINK_CHECK_TEMPLATE_CAPS = 1 << 1,
GST_PAD_LINK_CHECK_CAPS = 1 << 2
} GstPadLinkCheck;
/**
* GST_PAD_LINK_CHECK_DEFAULT:
*
* The default checks done when linking pads (i.e. the ones used by
* gst_pad_link()).
*
* Since: 0.10.30
*/
#define GST_PAD_LINK_CHECK_DEFAULT ((GstPadLinkCheck) (GST_PAD_LINK_CHECK_HIERARCHY | GST_PAD_LINK_CHECK_CAPS))
/**
* GstActivateMode:
* @GST_ACTIVATE_NONE: Pad will not handle dataflow
* @GST_ACTIVATE_PUSH: Pad handles dataflow in downstream push mode
* @GST_ACTIVATE_PULL: Pad handles dataflow in upstream pull mode
*
* The status of a GstPad. After activating a pad, which usually happens when the
* parent element goes from READY to PAUSED, the GstActivateMode defines if the
* pad operates in push or pull mode.
*/
typedef enum {
GST_ACTIVATE_NONE,
GST_ACTIVATE_PUSH,
GST_ACTIVATE_PULL
} GstActivateMode;
/**
* GST_PAD_MODE_ACTIVATE:
* @mode: a #GstActivateMode
*
* Macro to test if the given #GstActivateMode value indicates that datapassing
* is possible or not.
*/
#define GST_PAD_MODE_ACTIVATE(mode) ((mode) != GST_ACTIVATE_NONE)
/* pad states */
/**
* GstPadActivateFunction:
* @pad: a #GstPad
*
* This function is called when the pad is activated during the element
* READY to PAUSED state change. By default this function will call the
* activate function that puts the pad in push mode but elements can
* override this function to activate the pad in pull mode if they wish.
*
* Returns: TRUE if the pad could be activated.
*/
typedef gboolean (*GstPadActivateFunction) (GstPad *pad);
/**
* GstPadActivateModeFunction:
* @pad: a #GstPad
* @active: activate or deactivate the pad.
*
* The prototype of the push and pull activate functions.
*
* Returns: TRUE if the pad could be activated or deactivated.
*/
typedef gboolean (*GstPadActivateModeFunction) (GstPad *pad, gboolean active);
/* data passing */
/**
* GstPadChainFunction:
* @pad: the sink #GstPad that performed the chain.
* @buffer: the #GstBuffer that is chained, not %NULL.
*
* A function that will be called on sinkpads when chaining buffers.
* The function typically processes the data contained in the buffer and
* either consumes the data or passes it on to the internally linked pad(s).
*
* The implementer of this function receives a refcount to @buffer and should
* gst_buffer_unref() when the buffer is no longer needed.
*
* When a chain function detects an error in the data stream, it must post an
* error on the bus and return an appropriate #GstFlowReturn value.
*
* Returns: #GST_FLOW_OK for success
*/
typedef GstFlowReturn (*GstPadChainFunction) (GstPad *pad, GstBuffer *buffer);
/**
* GstPadChainListFunction:
* @pad: the sink #GstPad that performed the chain.
* @list: the #GstBufferList that is chained, not %NULL.
*
* A function that will be called on sinkpads when chaining buffer lists.
* The function typically processes the data contained in the buffer list and
* either consumes the data or passes it on to the internally linked pad(s).
*
* The implementer of this function receives a refcount to @list and
* should gst_buffer_list_unref() when the list is no longer needed.
*
* When a chainlist function detects an error in the data stream, it must
* post an error on the bus and return an appropriate #GstFlowReturn value.
*
* Returns: #GST_FLOW_OK for success
*/
typedef GstFlowReturn (*GstPadChainListFunction) (GstPad *pad, GstBufferList *list);
/**
* GstPadGetRangeFunction:
* @pad: the src #GstPad to perform the getrange on.
* @offset: the offset of the range
* @length: the length of the range
* @buffer: a memory location to hold the result buffer, cannot be NULL.
*
* This function will be called on source pads when a peer element
* request a buffer at the specified @offset and @length. If this function
* returns #GST_FLOW_OK, the result buffer will be stored in @buffer. The
* contents of @buffer is invalid for any other return value.
*
* This function is installed on a source pad with
* gst_pad_set_getrange_function() and can only be called on source pads after
* they are successfully activated with gst_pad_activate_pull().
*
* @offset and @length are always given in byte units. @offset must normally be a value
* between 0 and the length in bytes of the data available on @pad. The
* length (duration in bytes) can be retrieved with a #GST_QUERY_DURATION or with a
* #GST_QUERY_SEEKING.
*
* Any @offset larger or equal than the length will make the function return
* #GST_FLOW_UNEXPECTED, which corresponds to EOS. In this case @buffer does not
* contain a valid buffer.
*
* The buffer size of @buffer will only be smaller than @length when @offset is
* near the end of the stream. In all other cases, the size of @buffer must be
* exactly the requested size.
*
* It is allowed to call this function with a 0 @length and valid @offset, in
* which case @buffer will contain a 0-sized buffer and the function returns
* #GST_FLOW_OK.
*
* When this function is called with a -1 @offset, the sequentially next buffer
* of length @length in the stream is returned.
*
* When this function is called with a -1 @length, a buffer with a default
* optimal length is returned in @buffer. The length might depend on the value
* of @offset.
*
* Returns: #GST_FLOW_OK for success and a valid buffer in @buffer. Any other
* return value leaves @buffer undefined.
*/
typedef GstFlowReturn (*GstPadGetRangeFunction) (GstPad *pad, guint64 offset,
guint length, GstBuffer **buffer);
/**
* GstPadEventFunction:
* @pad: the #GstPad to handle the event.
* @event: the #GstEvent to handle.
*
* Function signature to handle an event for the pad.
*
* Returns: TRUE if the pad could handle the event.
*/
typedef gboolean (*GstPadEventFunction) (GstPad *pad, GstEvent *event);
/* FIXME: 0.11: deprecate me, check range should use seeking query */
/**
* GstPadCheckGetRangeFunction:
* @pad: a #GstPad
*
* Check if @pad can be activated in pull mode.
*
* This function will be deprecated after 0.10; use the seeking query to check
* if a pad can support random access.
*
* Returns: TRUE if the pad can operate in pull mode.
*/
typedef gboolean (*GstPadCheckGetRangeFunction) (GstPad *pad);
/* internal links */
/**
* GstPadIntLinkFunction:
* @pad: The #GstPad to query.
*
* The signature of the internal pad link function.
*
* Returns: (element-type Gst.Pad) (transfer container): a newly allocated #GList of pads that are linked to the given pad on
* the inside of the parent element.
*
* The caller must call g_list_free() on it after use.
*
* Deprecated: use the threadsafe #GstPadIterIntLinkFunction instead.
*/
#ifndef GST_DISABLE_DEPRECATED
typedef GList* (*GstPadIntLinkFunction) (GstPad *pad);
#endif
/**
* GstPadIterIntLinkFunction:
* @pad: The #GstPad to query.
*
* The signature of the internal pad link iterator function.
*
* Returns: a new #GstIterator that will iterate over all pads that are
* linked to the given pad on the inside of the parent element.
*
* the caller must call gst_iterator_free() after usage.
*
* Since 0.10.21
*/
typedef GstIterator* (*GstPadIterIntLinkFunction) (GstPad *pad);
/* generic query function */
/**
* GstPadQueryTypeFunction:
* @pad: a #GstPad to query
*
* The signature of the query types function.
*
* Returns: a constant array of query types
*/
typedef const GstQueryType* (*GstPadQueryTypeFunction) (GstPad *pad);
/**
* GstPadQueryFunction:
* @pad: the #GstPad to query.
* @query: the #GstQuery object to execute
*
* The signature of the query function.
*
* Returns: TRUE if the query could be performed.
*/
typedef gboolean (*GstPadQueryFunction) (GstPad *pad, GstQuery *query);
/* linking */
/**
* GstPadLinkFunction
* @pad: the #GstPad that is linked.
* @peer: the peer #GstPad of the link
*
* Function signature to handle a new link on the pad.
*
* Returns: the result of the link with the specified peer.
*/
typedef GstPadLinkReturn (*GstPadLinkFunction) (GstPad *pad, GstPad *peer);
/**
* GstPadUnlinkFunction
* @pad: the #GstPad that is linked.
*
* Function signature to handle a unlinking the pad prom its peer.
*/
typedef void (*GstPadUnlinkFunction) (GstPad *pad);
/* caps nego */
/**
* GstPadGetCapsFunction:
* @pad: the #GstPad to get the capabilities of.
*
* Returns a copy of the capabilities of the specified pad. By default this
* function will return the pad template capabilities, but can optionally
* be overridden by elements.
*
* Returns: a newly allocated copy #GstCaps of the pad.
*/
typedef GstCaps* (*GstPadGetCapsFunction) (GstPad *pad);
/**
* GstPadSetCapsFunction:
* @pad: the #GstPad to set the capabilities of.
* @caps: the #GstCaps to set
*
* Set @caps on @pad. By default this function updates the caps of the
* pad but the function can be overriden by elements to perform extra
* actions or verifications.
*
* Returns: TRUE if the caps could be set on the pad.
*/
typedef gboolean (*GstPadSetCapsFunction) (GstPad *pad, GstCaps *caps);
/**
* GstPadAcceptCapsFunction:
* @pad: the #GstPad to check
* @caps: the #GstCaps to check
*
* Check if @pad can accept @caps. By default this function will see if @caps
* intersect with the result from gst_pad_get_caps() by can be overridden to
* perform extra checks.
*
* Returns: TRUE if the caps can be accepted by the pad.
*/
typedef gboolean (*GstPadAcceptCapsFunction) (GstPad *pad, GstCaps *caps);
/**
* GstPadFixateCapsFunction:
* @pad: a #GstPad
* @caps: the #GstCaps to fixate
*
* Given possibly unfixed caps @caps, let @pad use its default preferred
* format to make a fixed caps. @caps should be writable. By default this
* function will pick the first value of any ranges or lists in the caps but
* elements can override this function to perform other behaviour.
*/
typedef void (*GstPadFixateCapsFunction) (GstPad *pad, GstCaps *caps);
/**
* GstPadBufferAllocFunction:
* @pad: a sink #GstPad
* @offset: the desired offset of the buffer
* @size: the desired size of the buffer
* @caps: the desired caps of the buffer
* @buf: pointer to hold the allocated buffer.
*
* Ask the sinkpad @pad to allocate a buffer with @offset, @size and @caps.
* The result will be stored in @buf.
*
* The purpose of this function is to allocate a buffer that is optimal to
* be processed by @pad. The function is mostly overridden by elements that can
* provide a hardware buffer in order to avoid additional memcpy operations.
*
* The function can return a buffer that has caps different from the requested
* @caps, in which case the upstream element requests a format change to this
* new caps.
* If a format change was requested, the returned buffer will be one to hold
* the data of said new caps, so its size might be different from the requested
* @size.
*
* When this function returns anything else than #GST_FLOW_OK, the buffer allocation
* failed and @buf does not contain valid data. If the function returns #GST_FLOW_OK and
* the @buf is NULL, a #GstBuffer will be created with @caps, @offset and @size.
*
* By default this function returns a new buffer of @size and with @caps containing
* purely malloced data. The buffer should be freed with gst_buffer_unref()
* after usage.
*
* Returns: #GST_FLOW_OK if @buf contains a valid buffer, any other return
* value means @buf does not hold a valid buffer.
*/
typedef GstFlowReturn (*GstPadBufferAllocFunction) (GstPad *pad, guint64 offset, guint size,
GstCaps *caps, GstBuffer **buf);
/* misc */
/**
* GstPadDispatcherFunction:
* @pad: the #GstPad that is dispatched.
* @data: the gpointer to optional user data.
*
* A dispatcher function is called for all internally linked pads, see
* gst_pad_dispatcher().
*
* Returns: TRUE if the dispatching procedure has to be stopped.
*/
typedef gboolean (*GstPadDispatcherFunction) (GstPad *pad, gpointer data);
/**
* GstPadBlockCallback:
* @pad: the #GstPad that is blockend or unblocked.
* @blocked: blocking state for the pad
* @user_data: the gpointer to optional user data.
*
* Callback used by gst_pad_set_blocked_async(). Gets called when the blocking
* operation succeeds.
*/
typedef void (*GstPadBlockCallback) (GstPad *pad, gboolean blocked, gpointer user_data);
/**
* GstPadDirection:
* @GST_PAD_UNKNOWN: direction is unknown.
* @GST_PAD_SRC: the pad is a source pad.
* @GST_PAD_SINK: the pad is a sink pad.
*
* The direction of a pad.
*/
typedef enum {
GST_PAD_UNKNOWN,
GST_PAD_SRC,
GST_PAD_SINK
} GstPadDirection;
/**
* GstPadFlags:
* @GST_PAD_BLOCKED: is dataflow on a pad blocked
* @GST_PAD_FLUSHING: is pad refusing buffers
* @GST_PAD_IN_GETCAPS: GstPadGetCapsFunction() is running now
* @GST_PAD_IN_SETCAPS: GstPadSetCapsFunction() is running now
* @GST_PAD_BLOCKING: is pad currently blocking on a buffer or event
* @GST_PAD_FLAG_LAST: offset to define more flags
*
* Pad state flags
*/
typedef enum {
GST_PAD_BLOCKED = (GST_OBJECT_FLAG_LAST << 0),
GST_PAD_FLUSHING = (GST_OBJECT_FLAG_LAST << 1),
GST_PAD_IN_GETCAPS = (GST_OBJECT_FLAG_LAST << 2),
GST_PAD_IN_SETCAPS = (GST_OBJECT_FLAG_LAST << 3),
GST_PAD_BLOCKING = (GST_OBJECT_FLAG_LAST << 4),
/* padding */
GST_PAD_FLAG_LAST = (GST_OBJECT_FLAG_LAST << 8)
} GstPadFlags;
/* FIXME: this awful circular dependency need to be resolved properly (see padtemplate.h) */
typedef struct _GstPadTemplate GstPadTemplate;
/**
* GstPad:
* @element_private: private data owned by the parent element
* @padtemplate: padtemplate for this pad
* @direction: the direction of the pad, cannot change after creating
* the pad.
* @stream_rec_lock: recursive stream lock of the pad, used to protect
* the data used in streaming.
* @task: task for this pad if the pad is actively driving dataflow.
* @preroll_lock: lock used when prerolling
* @preroll_cond: conf to signal preroll
* @block_cond: conditional to signal pad block
* @block_callback: callback for the pad block if any
* @block_data: user data for @block_callback
* @caps: the current caps of the pad
* @getcapsfunc: function to get caps of the pad
* @setcapsfunc: function to set caps on the pad
* @acceptcapsfunc: function to check if pad can accept caps
* @fixatecapsfunc: function to fixate caps
* @activatefunc: pad activation function
* @activatepushfunc: function to activate/deactivate pad in push mode
* @activatepullfunc: function to activate/deactivate pad in pull mode
* @linkfunc: function called when pad is linked
* @unlinkfunc: function called when pad is unlinked
* @peer: the pad this pad is linked to
* @sched_private: private storage for the scheduler
* @chainfunc: function to chain buffer to pad
* @checkgetrangefunc: function to check if pad can operate in pull mode
* @getrangefunc: function to get a range of data from a pad
* @eventfunc: function to send an event to a pad
* @mode: current activation mode of the pad
* @querytypefunc: get list of supported queries
* @queryfunc: perform a query on the pad
* @intlinkfunc: get the internal links of this pad
* @bufferallocfunc: function to allocate a buffer for this pad
* @do_buffer_signals: counter counting installed buffer signals
* @do_event_signals: counter counting installed event signals
* @iterintlinkfunc: get the internal links iterator of this pad
* @block_destroy_data: notify function for gst_pad_set_blocked_async_full()
*
* The #GstPad structure. Use the functions to update the variables.
*/
struct _GstPad {
GstObject object;
/*< public >*/
gpointer element_private;
GstPadTemplate *padtemplate;
GstPadDirection direction;
/*< public >*/ /* with STREAM_LOCK */
/* streaming rec_lock */
GStaticRecMutex *stream_rec_lock;
GstTask *task;
/*< public >*/ /* with PREROLL_LOCK */
GMutex *preroll_lock;
GCond *preroll_cond;
/*< public >*/ /* with LOCK */
/* block cond, mutex is from the object */
GCond *block_cond;
GstPadBlockCallback block_callback;
gpointer block_data;
/* the pad capabilities */
GstCaps *caps;
GstPadGetCapsFunction getcapsfunc;
GstPadSetCapsFunction setcapsfunc;
GstPadAcceptCapsFunction acceptcapsfunc;
GstPadFixateCapsFunction fixatecapsfunc;
GstPadActivateFunction activatefunc;
GstPadActivateModeFunction activatepushfunc;
GstPadActivateModeFunction activatepullfunc;
/* pad link */
GstPadLinkFunction linkfunc;
GstPadUnlinkFunction unlinkfunc;
GstPad *peer;
gpointer sched_private;
/* data transport functions */
GstPadChainFunction chainfunc;
GstPadCheckGetRangeFunction checkgetrangefunc;
GstPadGetRangeFunction getrangefunc;
GstPadEventFunction eventfunc;
GstActivateMode mode;
/* generic query method */
GstPadQueryTypeFunction querytypefunc;
GstPadQueryFunction queryfunc;
/* internal links */
#ifndef GST_DISABLE_DEPRECATED
GstPadIntLinkFunction intlinkfunc;
#else
#ifndef __GTK_DOC_IGNORE__
gpointer intlinkfunc;
#endif
#endif
GstPadBufferAllocFunction bufferallocfunc;
/* whether to emit signals for have-data. counts number
* of handlers attached. */
gint do_buffer_signals;
gint do_event_signals;
/* ABI added */
/* iterate internal links */
GstPadIterIntLinkFunction iterintlinkfunc;
/* free block_data */
GDestroyNotify block_destroy_data;
/*< private >*/
union {
struct {
gboolean block_callback_called;
GstPadPrivate *priv;
} ABI;
gpointer _gst_reserved[GST_PADDING - 2];
} abidata;
};
struct _GstPadClass {
GstObjectClass parent_class;
/* signal callbacks */
void (*linked) (GstPad *pad, GstPad *peer);
void (*unlinked) (GstPad *pad, GstPad *peer);
void (*request_link) (GstPad *pad);
gboolean (*have_data) (GstPad *pad, GstMiniObject *data);
/*< private >*/
gpointer _gst_reserved[GST_PADDING];
};
/***** helper macros *****/
/* GstPad */
#define GST_PAD_NAME(pad) (GST_OBJECT_NAME(pad))
#define GST_PAD_PARENT(pad) (GST_ELEMENT_CAST(GST_OBJECT_PARENT(pad)))
#define GST_PAD_ELEMENT_PRIVATE(pad) (GST_PAD_CAST(pad)->element_private)
#define GST_PAD_PAD_TEMPLATE(pad) (GST_PAD_CAST(pad)->padtemplate)
#define GST_PAD_DIRECTION(pad) (GST_PAD_CAST(pad)->direction)
#define GST_PAD_TASK(pad) (GST_PAD_CAST(pad)->task)
#define GST_PAD_ACTIVATE_MODE(pad) (GST_PAD_CAST(pad)->mode)
#define GST_PAD_ACTIVATEFUNC(pad) (GST_PAD_CAST(pad)->activatefunc)
#define GST_PAD_ACTIVATEPUSHFUNC(pad) (GST_PAD_CAST(pad)->activatepushfunc)
#define GST_PAD_ACTIVATEPULLFUNC(pad) (GST_PAD_CAST(pad)->activatepullfunc)
#define GST_PAD_CHAINFUNC(pad) (GST_PAD_CAST(pad)->chainfunc)
#define GST_PAD_CHECKGETRANGEFUNC(pad) (GST_PAD_CAST(pad)->checkgetrangefunc)
#define GST_PAD_GETRANGEFUNC(pad) (GST_PAD_CAST(pad)->getrangefunc)
#define GST_PAD_EVENTFUNC(pad) (GST_PAD_CAST(pad)->eventfunc)
#define GST_PAD_QUERYTYPEFUNC(pad) (GST_PAD_CAST(pad)->querytypefunc)
#define GST_PAD_QUERYFUNC(pad) (GST_PAD_CAST(pad)->queryfunc)
#ifndef GST_DISABLE_DEPRECATED
#define GST_PAD_INTLINKFUNC(pad) (GST_PAD_CAST(pad)->intlinkfunc)
#endif
#define GST_PAD_ITERINTLINKFUNC(pad) (GST_PAD_CAST(pad)->iterintlinkfunc)
#define GST_PAD_PEER(pad) (GST_PAD_CAST(pad)->peer)
#define GST_PAD_LINKFUNC(pad) (GST_PAD_CAST(pad)->linkfunc)
#define GST_PAD_UNLINKFUNC(pad) (GST_PAD_CAST(pad)->unlinkfunc)
/**
* GST_PAD_CAPS:
* @pad: a #GstPad.
*
* The caps for this pad.
*/
#define GST_PAD_CAPS(pad) (GST_PAD_CAST(pad)->caps)
#define GST_PAD_GETCAPSFUNC(pad) (GST_PAD_CAST(pad)->getcapsfunc)
#define GST_PAD_SETCAPSFUNC(pad) (GST_PAD_CAST(pad)->setcapsfunc)
#define GST_PAD_ACCEPTCAPSFUNC(pad) (GST_PAD_CAST(pad)->acceptcapsfunc)
#define GST_PAD_FIXATECAPSFUNC(pad) (GST_PAD_CAST(pad)->fixatecapsfunc)
#define GST_PAD_BUFFERALLOCFUNC(pad) (GST_PAD_CAST(pad)->bufferallocfunc)
#define GST_PAD_DO_BUFFER_SIGNALS(pad) (GST_PAD_CAST(pad)->do_buffer_signals)
#define GST_PAD_DO_EVENT_SIGNALS(pad) (GST_PAD_CAST(pad)->do_event_signals)
#define GST_PAD_IS_LINKED(pad) (GST_PAD_PEER(pad) != NULL)
#define GST_PAD_IS_BLOCKED(pad) (GST_OBJECT_FLAG_IS_SET (pad, GST_PAD_BLOCKED))
#define GST_PAD_IS_BLOCKING(pad) (GST_OBJECT_FLAG_IS_SET (pad, GST_PAD_BLOCKING))
#define GST_PAD_IS_FLUSHING(pad) (GST_OBJECT_FLAG_IS_SET (pad, GST_PAD_FLUSHING))
#define GST_PAD_IS_IN_GETCAPS(pad) (GST_OBJECT_FLAG_IS_SET (pad, GST_PAD_IN_GETCAPS))
#define GST_PAD_IS_IN_SETCAPS(pad) (GST_OBJECT_FLAG_IS_SET (pad, GST_PAD_IN_SETCAPS))
#define GST_PAD_IS_SRC(pad) (GST_PAD_DIRECTION(pad) == GST_PAD_SRC)
#define GST_PAD_IS_SINK(pad) (GST_PAD_DIRECTION(pad) == GST_PAD_SINK)
#define GST_PAD_SET_FLUSHING(pad) (GST_OBJECT_FLAG_SET (pad, GST_PAD_FLUSHING))
#define GST_PAD_UNSET_FLUSHING(pad) (GST_OBJECT_FLAG_UNSET (pad, GST_PAD_FLUSHING))
/**
* GST_PAD_GET_STREAM_LOCK:
* @pad: a #GstPad
*
* Get the stream lock of @pad. The stream lock is protecting the
* resources used in the data processing functions of @pad.
*/
#define GST_PAD_GET_STREAM_LOCK(pad) (GST_PAD_CAST(pad)->stream_rec_lock)
/**
* GST_PAD_STREAM_LOCK:
* @pad: a #GstPad
*
* Lock the stream lock of @pad.
*/
#define GST_PAD_STREAM_LOCK(pad) (g_static_rec_mutex_lock(GST_PAD_GET_STREAM_LOCK(pad)))
/**
* GST_PAD_STREAM_LOCK_FULL:
* @pad: a #GstPad
* @t: the number of times to recursively lock
*
* Lock the stream lock of @pad @t times.
*/
#define GST_PAD_STREAM_LOCK_FULL(pad,t) (g_static_rec_mutex_lock_full(GST_PAD_GET_STREAM_LOCK(pad), t))
/**
* GST_PAD_STREAM_TRYLOCK:
* @pad: a #GstPad
*
* Try to Lock the stream lock of the pad, return TRUE if the lock could be
* taken.
*/
#define GST_PAD_STREAM_TRYLOCK(pad) (g_static_rec_mutex_trylock(GST_PAD_GET_STREAM_LOCK(pad)))
/**
* GST_PAD_STREAM_UNLOCK:
* @pad: a #GstPad
*
* Unlock the stream lock of @pad.
*/
#define GST_PAD_STREAM_UNLOCK(pad) (g_static_rec_mutex_unlock(GST_PAD_GET_STREAM_LOCK(pad)))
/**
* GST_PAD_STREAM_UNLOCK_FULL:
* @pad: a #GstPad
*
* Fully unlock the recursive stream lock of @pad, return the number of times
* @pad was locked.
*/
#define GST_PAD_STREAM_UNLOCK_FULL(pad) (g_static_rec_mutex_unlock_full(GST_PAD_GET_STREAM_LOCK(pad)))
#define GST_PAD_GET_PREROLL_LOCK(pad) (GST_PAD_CAST(pad)->preroll_lock)
#define GST_PAD_PREROLL_LOCK(pad) (g_mutex_lock(GST_PAD_GET_PREROLL_LOCK(pad)))
#define GST_PAD_PREROLL_TRYLOCK(pad) (g_mutex_trylock(GST_PAD_GET_PREROLL_LOCK(pad)))
#define GST_PAD_PREROLL_UNLOCK(pad) (g_mutex_unlock(GST_PAD_GET_PREROLL_LOCK(pad)))
#define GST_PAD_GET_PREROLL_COND(pad) (GST_PAD_CAST(pad)->preroll_cond)
#define GST_PAD_PREROLL_WAIT(pad) \
g_cond_wait (GST_PAD_GET_PREROLL_COND (pad), GST_PAD_GET_PREROLL_LOCK (pad))
#define GST_PAD_PREROLL_TIMED_WAIT(pad, timeval) \
g_cond_timed_wait (GST_PAD_GET_PREROLL_COND (pad), GST_PAD_GET_PREROLL_LOCK (pad), timeval)
#define GST_PAD_PREROLL_SIGNAL(pad) g_cond_signal (GST_PAD_GET_PREROLL_COND (pad));
#define GST_PAD_PREROLL_BROADCAST(pad) g_cond_broadcast (GST_PAD_GET_PREROLL_COND (pad));
#define GST_PAD_BLOCK_GET_COND(pad) (GST_PAD_CAST(pad)->block_cond)
#define GST_PAD_BLOCK_WAIT(pad) (g_cond_wait(GST_PAD_BLOCK_GET_COND (pad), GST_OBJECT_GET_LOCK (pad)))
#define GST_PAD_BLOCK_SIGNAL(pad) (g_cond_signal(GST_PAD_BLOCK_GET_COND (pad)))
#define GST_PAD_BLOCK_BROADCAST(pad) (g_cond_broadcast(GST_PAD_BLOCK_GET_COND (pad)))
/* FIXME: this awful circular dependency need to be resolved properly (see padtemplate.h) */
#include <gst/gstpadtemplate.h>
GType gst_pad_get_type (void);
/* creating pads */
GstPad* gst_pad_new (const gchar *name, GstPadDirection direction);
GstPad* gst_pad_new_from_template (GstPadTemplate *templ, const gchar *name);
GstPad* gst_pad_new_from_static_template (GstStaticPadTemplate *templ, const gchar *name);
/**
* gst_pad_get_name:
* @pad: the pad to get the name from
*
* Get a copy of the name of the pad. g_free() after usage.
*
* MT safe.
*/
#define gst_pad_get_name(pad) gst_object_get_name (GST_OBJECT_CAST (pad))
/**
* gst_pad_get_parent:
* @pad: the pad to get the parent of
*
* Get the parent of @pad. This function increases the refcount
* of the parent object so you should gst_object_unref() it after usage.
* Can return NULL if the pad did not have a parent.
*
* MT safe.
*/
#define gst_pad_get_parent(pad) gst_object_get_parent (GST_OBJECT_CAST (pad))
GstPadDirection gst_pad_get_direction (GstPad *pad);
gboolean gst_pad_set_active (GstPad *pad, gboolean active);
gboolean gst_pad_is_active (GstPad *pad);
gboolean gst_pad_activate_pull (GstPad *pad, gboolean active);
gboolean gst_pad_activate_push (GstPad *pad, gboolean active);
gboolean gst_pad_set_blocked (GstPad *pad, gboolean blocked);
gboolean gst_pad_set_blocked_async (GstPad *pad, gboolean blocked,
GstPadBlockCallback callback, gpointer user_data);
gboolean gst_pad_set_blocked_async_full (GstPad *pad, gboolean blocked,
GstPadBlockCallback callback, gpointer user_data,
GDestroyNotify destroy_data);
gboolean gst_pad_is_blocked (GstPad *pad);
gboolean gst_pad_is_blocking (GstPad *pad);
void gst_pad_set_element_private (GstPad *pad, gpointer priv);
gpointer gst_pad_get_element_private (GstPad *pad);
GstPadTemplate* gst_pad_get_pad_template (GstPad *pad);
void gst_pad_set_bufferalloc_function (GstPad *pad, GstPadBufferAllocFunction bufalloc);
GstFlowReturn gst_pad_alloc_buffer (GstPad *pad, guint64 offset, gint size,
GstCaps *caps, GstBuffer **buf);
GstFlowReturn gst_pad_alloc_buffer_and_set_caps (GstPad *pad, guint64 offset, gint size,
GstCaps *caps, GstBuffer **buf);
/* data passing setup functions */
void gst_pad_set_activate_function (GstPad *pad, GstPadActivateFunction activate);
void gst_pad_set_activatepull_function (GstPad *pad, GstPadActivateModeFunction activatepull);
void gst_pad_set_activatepush_function (GstPad *pad, GstPadActivateModeFunction activatepush);
void gst_pad_set_chain_function (GstPad *pad, GstPadChainFunction chain);
void gst_pad_set_chain_list_function (GstPad *pad, GstPadChainListFunction chainlist);
void gst_pad_set_getrange_function (GstPad *pad, GstPadGetRangeFunction get);
void gst_pad_set_checkgetrange_function (GstPad *pad, GstPadCheckGetRangeFunction check);
void gst_pad_set_event_function (GstPad *pad, GstPadEventFunction event);
/* pad links */
void gst_pad_set_link_function (GstPad *pad, GstPadLinkFunction link);
void gst_pad_set_unlink_function (GstPad *pad, GstPadUnlinkFunction unlink);
gboolean gst_pad_can_link (GstPad *srcpad, GstPad *sinkpad);
GstPadLinkReturn gst_pad_link (GstPad *srcpad, GstPad *sinkpad);
GstPadLinkReturn gst_pad_link_full (GstPad *srcpad, GstPad *sinkpad, GstPadLinkCheck flags);
gboolean gst_pad_unlink (GstPad *srcpad, GstPad *sinkpad);
gboolean gst_pad_is_linked (GstPad *pad);
GstPad* gst_pad_get_peer (GstPad *pad);
/* capsnego functions */
void gst_pad_set_getcaps_function (GstPad *pad, GstPadGetCapsFunction getcaps);
void gst_pad_set_acceptcaps_function (GstPad *pad, GstPadAcceptCapsFunction acceptcaps);
void gst_pad_set_fixatecaps_function (GstPad *pad, GstPadFixateCapsFunction fixatecaps);
void gst_pad_set_setcaps_function (GstPad *pad, GstPadSetCapsFunction setcaps);
const GstCaps* gst_pad_get_pad_template_caps (GstPad *pad);
/* capsnego function for linked/unlinked pads */
GstCaps * gst_pad_get_caps_reffed (GstPad * pad);
GstCaps * gst_pad_get_caps (GstPad * pad);
void gst_pad_fixate_caps (GstPad * pad, GstCaps *caps);
gboolean gst_pad_accept_caps (GstPad * pad, GstCaps *caps);
gboolean gst_pad_set_caps (GstPad * pad, GstCaps *caps);
GstCaps * gst_pad_peer_get_caps_reffed (GstPad * pad);
GstCaps * gst_pad_peer_get_caps (GstPad * pad);
gboolean gst_pad_peer_accept_caps (GstPad * pad, GstCaps *caps);
/* capsnego for linked pads */
GstCaps * gst_pad_get_allowed_caps (GstPad * pad);
GstCaps * gst_pad_get_negotiated_caps (GstPad * pad);
/* data passing functions to peer */
GstFlowReturn gst_pad_push (GstPad *pad, GstBuffer *buffer);
GstFlowReturn gst_pad_push_list (GstPad *pad, GstBufferList *list);
gboolean gst_pad_check_pull_range (GstPad *pad);
GstFlowReturn gst_pad_pull_range (GstPad *pad, guint64 offset, guint size,
GstBuffer **buffer);
gboolean gst_pad_push_event (GstPad *pad, GstEvent *event);
gboolean gst_pad_event_default (GstPad *pad, GstEvent *event);
/* data passing functions on pad */
GstFlowReturn gst_pad_chain (GstPad *pad, GstBuffer *buffer);
GstFlowReturn gst_pad_chain_list (GstPad *pad, GstBufferList *list);
GstFlowReturn gst_pad_get_range (GstPad *pad, guint64 offset, guint size,
GstBuffer **buffer);
gboolean gst_pad_send_event (GstPad *pad, GstEvent *event);
/* pad tasks */
gboolean gst_pad_start_task (GstPad *pad, GstTaskFunction func,
gpointer data);
gboolean gst_pad_pause_task (GstPad *pad);
gboolean gst_pad_stop_task (GstPad *pad);
/* internal links */
#ifndef GST_DISABLE_DEPRECATED
void gst_pad_set_internal_link_function (GstPad *pad, GstPadIntLinkFunction intlink);
GList* gst_pad_get_internal_links (GstPad *pad);
GList* gst_pad_get_internal_links_default (GstPad *pad);
#endif
void gst_pad_set_iterate_internal_links_function (GstPad * pad,
GstPadIterIntLinkFunction iterintlink);
GstIterator * gst_pad_iterate_internal_links (GstPad * pad);
GstIterator * gst_pad_iterate_internal_links_default (GstPad * pad);
/* generic query function */
void gst_pad_set_query_type_function (GstPad *pad, GstPadQueryTypeFunction type_func);
const GstQueryType* gst_pad_get_query_types (GstPad *pad);
const GstQueryType* gst_pad_get_query_types_default (GstPad *pad);
gboolean gst_pad_query (GstPad *pad, GstQuery *query);
gboolean gst_pad_peer_query (GstPad *pad, GstQuery *query);
void gst_pad_set_query_function (GstPad *pad, GstPadQueryFunction query);
gboolean gst_pad_query_default (GstPad *pad, GstQuery *query);
/* misc helper functions */
gboolean gst_pad_dispatcher (GstPad *pad, GstPadDispatcherFunction dispatch,
gpointer data);
#if !defined(GST_DISABLE_LOADSAVE) && !defined(GST_DISABLE_DEPRECATED)
void gst_pad_load_and_link (xmlNodePtr self, GstObject *parent);
#endif
G_END_DECLS
#endif /* __GST_PAD_H__ */