--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/gstreamer_core/gst/gstpad.h Thu Dec 17 08:53:32 2009 +0200
@@ -0,0 +1,1145 @@
+/* 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/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 _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_CUSTOM_SUCCESS: Elements can use values starting from
+ * this to define custom success codes.
+ * Since 0.10.7.
+ * @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_ERROR: Elements can use values starting from
+ * this to define custom error codes. Since 0.10.7.
+ *
+ * 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.
+ */
+typedef enum {
+ /* custom success starts here */
+ 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
+} 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.
+ */
+#define GST_FLOW_IS_FATAL(ret) ((ret) <= GST_FLOW_UNEXPECTED)
+
+/**
+ * GST_FLOW_IS_SUCCESS:
+ * @ret: a #GstFlowReturn value
+ *
+ * Macro to test if the given #GstFlowReturn value indicates a
+ * successfull result
+ * This macro is mainly used in elements to decide if the processing
+ * of a buffer was successfull.
+ *
+ * Since: 0.10.7
+ */
+#define GST_FLOW_IS_SUCCESS(ret) ((ret) >= GST_FLOW_OK)
+
+G_CONST_RETURN gchar* gst_flow_get_name (GstFlowReturn ret);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+GQuark gst_flow_to_quark (GstFlowReturn ret);
+
+/**
+ * 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 buffer and return an appropriate #GstFlowReturn value.
+ *
+ * Returns: #GST_FLOW_OK for success
+ */
+typedef GstFlowReturn (*GstPadChainFunction) (GstPad *pad, GstBuffer *buffer);
+/**
+ * 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 might be smaller than @length when @offset is near
+ * the end of the stream.
+ *
+ * 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
+ */
+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: 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.
+ */
+typedef GList* (*GstPadIntLinkFunction) (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 prefered
+ * 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 does not have @caps, in which case the
+ * upstream element requests a format change. 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 @size.
+ *
+ * When this function returns anything else than #GST_FLOW_OK, the buffer allocation
+ * failed and @buf does not contain valid data.
+ *
+ * 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 data 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
+ *
+ * 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 */
+ GstPadIntLinkFunction intlinkfunc;
+
+ GstPadBufferAllocFunction bufferallocfunc;
+
+ /* whether to emit signals for have-data. counts number
+ * of handlers attached. */
+ gint do_buffer_signals;
+ gint do_event_signals;
+
+ /*< private >*/
+ gpointer _gst_reserved[GST_PADDING];
+};
+
+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)
+#define GST_PAD_INTLINKFUNC(pad) (GST_PAD_CAST(pad)->intlinkfunc)
+
+#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)
+
+#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 */
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+GstPad* gst_pad_new (const gchar *name, GstPadDirection direction);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+GstPad* gst_pad_new_from_template (GstPadTemplate *templ, const gchar *name);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+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);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+
+gboolean gst_pad_set_active (GstPad *pad, gboolean active);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+gboolean gst_pad_is_active (GstPad *pad);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+gboolean gst_pad_activate_pull (GstPad *pad, gboolean active);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+gboolean gst_pad_activate_push (GstPad *pad, gboolean active);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+
+gboolean gst_pad_set_blocked (GstPad *pad, gboolean blocked);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+gboolean gst_pad_set_blocked_async (GstPad *pad, gboolean blocked,
+ GstPadBlockCallback callback, gpointer user_data);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+gboolean gst_pad_is_blocked (GstPad *pad);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+gboolean gst_pad_is_blocking (GstPad *pad);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+
+void gst_pad_set_element_private (GstPad *pad, gpointer priv);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+gpointer gst_pad_get_element_private (GstPad *pad);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+
+GstPadTemplate* gst_pad_get_pad_template (GstPad *pad);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+
+void gst_pad_set_bufferalloc_function (GstPad *pad, GstPadBufferAllocFunction bufalloc);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+GstFlowReturn gst_pad_alloc_buffer (GstPad *pad, guint64 offset, gint size,
+ GstCaps *caps, GstBuffer **buf);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+GstFlowReturn gst_pad_alloc_buffer_and_set_caps (GstPad *pad, guint64 offset, gint size,
+ GstCaps *caps, GstBuffer **buf);
+
+/* data passing setup functions */
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+void gst_pad_set_activate_function (GstPad *pad, GstPadActivateFunction activate);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+void gst_pad_set_activatepull_function (GstPad *pad, GstPadActivateModeFunction activatepull);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+void gst_pad_set_activatepush_function (GstPad *pad, GstPadActivateModeFunction activatepush);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+void gst_pad_set_chain_function (GstPad *pad, GstPadChainFunction chain);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+void gst_pad_set_getrange_function (GstPad *pad, GstPadGetRangeFunction get);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+void gst_pad_set_checkgetrange_function (GstPad *pad, GstPadCheckGetRangeFunction check);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+void gst_pad_set_event_function (GstPad *pad, GstPadEventFunction event);
+
+/* pad links */
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+void gst_pad_set_link_function (GstPad *pad, GstPadLinkFunction link);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+void gst_pad_set_unlink_function (GstPad *pad, GstPadUnlinkFunction unlink);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+
+GstPadLinkReturn gst_pad_link (GstPad *srcpad, GstPad *sinkpad);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+gboolean gst_pad_unlink (GstPad *srcpad, GstPad *sinkpad);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+gboolean gst_pad_is_linked (GstPad *pad);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+
+GstPad* gst_pad_get_peer (GstPad *pad);
+
+/* capsnego functions */
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+void gst_pad_set_getcaps_function (GstPad *pad, GstPadGetCapsFunction getcaps);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+void gst_pad_set_acceptcaps_function (GstPad *pad, GstPadAcceptCapsFunction acceptcaps);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+void gst_pad_set_fixatecaps_function (GstPad *pad, GstPadFixateCapsFunction fixatecaps);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+void gst_pad_set_setcaps_function (GstPad *pad, GstPadSetCapsFunction setcaps);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+
+G_CONST_RETURN GstCaps* gst_pad_get_pad_template_caps (GstPad *pad);
+
+/* capsnego function for connected/unconnected pads */
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+GstCaps * gst_pad_get_caps (GstPad * pad);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+void gst_pad_fixate_caps (GstPad * pad, GstCaps *caps);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+gboolean gst_pad_accept_caps (GstPad * pad, GstCaps *caps);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+gboolean gst_pad_set_caps (GstPad * pad, GstCaps *caps);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+
+GstCaps * gst_pad_peer_get_caps (GstPad * pad);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+gboolean gst_pad_peer_accept_caps (GstPad * pad, GstCaps *caps);
+
+/* capsnego for connected pads */
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+GstCaps * gst_pad_get_allowed_caps (GstPad * pad);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+GstCaps * gst_pad_get_negotiated_caps (GstPad * pad);
+
+/* data passing functions to peer */
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+GstFlowReturn gst_pad_push (GstPad *pad, GstBuffer *buffer);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+gboolean gst_pad_check_pull_range (GstPad *pad);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+GstFlowReturn gst_pad_pull_range (GstPad *pad, guint64 offset, guint size,
+ GstBuffer **buffer);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+gboolean gst_pad_push_event (GstPad *pad, GstEvent *event);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+gboolean gst_pad_event_default (GstPad *pad, GstEvent *event);
+
+/* data passing functions on pad */
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+GstFlowReturn gst_pad_chain (GstPad *pad, GstBuffer *buffer);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+GstFlowReturn gst_pad_get_range (GstPad *pad, guint64 offset, guint size,
+ GstBuffer **buffer);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+gboolean gst_pad_send_event (GstPad *pad, GstEvent *event);
+
+/* pad tasks */
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+gboolean gst_pad_start_task (GstPad *pad, GstTaskFunction func,
+ gpointer data);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+gboolean gst_pad_pause_task (GstPad *pad);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+gboolean gst_pad_stop_task (GstPad *pad);
+
+/* internal links */
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+void gst_pad_set_internal_link_function (GstPad *pad, GstPadIntLinkFunction intlink);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+GList* gst_pad_get_internal_links (GstPad *pad);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+GList* gst_pad_get_internal_links_default (GstPad *pad);
+
+/* generic query function */
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+void gst_pad_set_query_type_function (GstPad *pad, GstPadQueryTypeFunction type_func);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+G_CONST_RETURN GstQueryType*
+ gst_pad_get_query_types (GstPad *pad);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+G_CONST_RETURN GstQueryType*
+ gst_pad_get_query_types_default (GstPad *pad);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+
+gboolean gst_pad_query (GstPad *pad, GstQuery *query);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+gboolean gst_pad_peer_query (GstPad *pad, GstQuery *query);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+void gst_pad_set_query_function (GstPad *pad, GstPadQueryFunction query);
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+gboolean gst_pad_query_default (GstPad *pad, GstQuery *query);
+
+/* misc helper functions */
+#ifdef __SYMBIAN32__
+IMPORT_C
+#endif
+
+gboolean gst_pad_dispatcher (GstPad *pad, GstPadDispatcherFunction dispatch,
+ gpointer data);
+
+#ifndef GST_DISABLE_LOADSAVE
+void gst_pad_load_and_link (xmlNodePtr self, GstObject *parent);
+#endif
+
+G_END_DECLS
+
+#endif /* __GST_PAD_H__ */