gstreamer/gst/gstelement.c

1227 lines
36 KiB
C
Raw Normal View History

/* GStreamer
* Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
* 2000 Wim Taymans <wtay@chello.be>
*
* gstelement.c: The base element, all elements derive from this
*
* 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.
*/
//#define GST_DEBUG_ENABLED
#include "gst_private.h"
#include "gstelement.h"
#include "gstextratypes.h"
#include "gstbin.h"
#include "gstscheduler.h"
#include "gstutils.h"
/* Element signals and args */
enum {
STATE_CHANGE,
NEW_PAD,
PAD_REMOVED,
NEW_GHOST_PAD,
GHOST_PAD_REMOVED,
ERROR,
EOS,
LAST_SIGNAL
};
enum {
ARG_0,
/* FILL ME */
};
static void gst_element_class_init (GstElementClass *klass);
static void gst_element_init (GstElement *element);
static void gst_element_set_arg (GtkObject *object, GtkArg *arg, guint id);
static void gst_element_get_arg (GtkObject *object, GtkArg *arg, guint id);
static void gst_element_shutdown (GtkObject *object);
static void gst_element_real_destroy (GtkObject *object);
static GstElementStateReturn gst_element_change_state (GstElement *element);
static xmlNodePtr gst_element_save_thyself (GstObject *object, xmlNodePtr parent);
static GstObjectClass *parent_class = NULL;
static guint gst_element_signals[LAST_SIGNAL] = { 0 };
GtkType gst_element_get_type(void) {
static GtkType element_type = 0;
if (!element_type) {
static const GtkTypeInfo element_info = {
"GstElement",
sizeof(GstElement),
sizeof(GstElementClass),
(GtkClassInitFunc)gst_element_class_init,
(GtkObjectInitFunc)gst_element_init,
(GtkArgSetFunc)gst_element_set_arg,
(GtkArgGetFunc)gst_element_get_arg,
(GtkClassInitFunc)NULL,
};
element_type = gtk_type_unique(GST_TYPE_OBJECT,&element_info);
}
return element_type;
}
static void
gst_element_class_init (GstElementClass *klass)
{
GtkObjectClass *gtkobject_class;
GstObjectClass *gstobject_class;
gtkobject_class = (GtkObjectClass*) klass;
gstobject_class = (GstObjectClass*) klass;
parent_class = gtk_type_class(GST_TYPE_OBJECT);
gst_element_signals[STATE_CHANGE] =
gtk_signal_new ("state_change", GTK_RUN_LAST, gtkobject_class->type,
GTK_SIGNAL_OFFSET (GstElementClass, state_change),
gtk_marshal_NONE__INT, GTK_TYPE_NONE, 1,
GTK_TYPE_INT);
gst_element_signals[NEW_PAD] =
gtk_signal_new ("new_pad", GTK_RUN_LAST, gtkobject_class->type,
GTK_SIGNAL_OFFSET (GstElementClass, new_pad),
gtk_marshal_NONE__POINTER, GTK_TYPE_NONE, 1,
GST_TYPE_PAD);
gst_element_signals[PAD_REMOVED] =
gtk_signal_new ("pad_removed", GTK_RUN_LAST, gtkobject_class->type,
GTK_SIGNAL_OFFSET (GstElementClass, pad_removed),
gtk_marshal_NONE__POINTER, GTK_TYPE_NONE, 1,
GST_TYPE_PAD);
gst_element_signals[NEW_GHOST_PAD] =
gtk_signal_new ("new_ghost_pad", GTK_RUN_LAST, gtkobject_class->type,
GTK_SIGNAL_OFFSET (GstElementClass, new_ghost_pad),
gtk_marshal_NONE__POINTER, GTK_TYPE_NONE, 1,
GST_TYPE_PAD);
gst_element_signals[GHOST_PAD_REMOVED] =
gtk_signal_new ("ghost_pad_removed", GTK_RUN_LAST, gtkobject_class->type,
GTK_SIGNAL_OFFSET (GstElementClass, ghost_pad_removed),
gtk_marshal_NONE__POINTER, GTK_TYPE_NONE, 1,
GST_TYPE_PAD);
gst_element_signals[ERROR] =
gtk_signal_new ("error", GTK_RUN_LAST, gtkobject_class->type,
GTK_SIGNAL_OFFSET (GstElementClass, error),
gtk_marshal_NONE__STRING, GTK_TYPE_NONE,1,
GTK_TYPE_STRING);
gst_element_signals[EOS] =
gtk_signal_new ("eos", GTK_RUN_LAST, gtkobject_class->type,
GTK_SIGNAL_OFFSET (GstElementClass,eos),
gtk_marshal_NONE__NONE, GTK_TYPE_NONE, 0);
gtk_object_class_add_signals (gtkobject_class, gst_element_signals, LAST_SIGNAL);
gtkobject_class->set_arg = GST_DEBUG_FUNCPTR(gst_element_set_arg);
gtkobject_class->get_arg = GST_DEBUG_FUNCPTR(gst_element_get_arg);
gtkobject_class->shutdown = GST_DEBUG_FUNCPTR(gst_element_shutdown);
gtkobject_class->destroy = GST_DEBUG_FUNCPTR(gst_element_real_destroy);
gstobject_class->save_thyself = GST_DEBUG_FUNCPTR(gst_element_save_thyself);
gstobject_class->restore_thyself = GST_DEBUG_FUNCPTR(gst_element_restore_thyself);
klass->change_state = GST_DEBUG_FUNCPTR(gst_element_change_state);
klass->elementfactory = NULL;
}
static void
gst_element_init (GstElement *element)
{
element->current_state = GST_STATE_NULL;
element->pending_state = -1;
element->numpads = 0;
element->numsrcpads = 0;
element->numsinkpads = 0;
element->pads = NULL;
element->loopfunc = NULL;
element->threadstate = NULL;
element->sched = NULL;
}
static void
gst_element_set_arg (GtkObject *object, GtkArg *arg, guint id)
{
GstElementClass *oclass = GST_ELEMENT_CLASS (object->klass);
GST_SCHEDULE_LOCK_ELEMENT ( GST_ELEMENT_SCHED(object), GST_ELEMENT(object) );
if (oclass->set_arg)
(oclass->set_arg)(object,arg,id);
GST_SCHEDULE_UNLOCK_ELEMENT ( GST_ELEMENT_SCHED(object), GST_ELEMENT(object) );
}
static void
gst_element_get_arg (GtkObject *object, GtkArg *arg, guint id)
{
GstElementClass *oclass = GST_ELEMENT_CLASS (object->klass);
GST_SCHEDULE_LOCK_ELEMENT (GST_ELEMENT_SCHED(object), GST_ELEMENT(object) );
if (oclass->get_arg)
(oclass->get_arg)(object,arg,id);
GST_SCHEDULE_UNLOCK_ELEMENT (GST_ELEMENT_SCHED(object), GST_ELEMENT(object) );
}
/**
* gst_element_new:
*
* Create a new element. Should never be used, as it does no good.
*
* Returns: new element
*/
GstElement*
gst_element_new(void)
{
return GST_ELEMENT (gtk_type_new (GST_TYPE_ELEMENT));
}
/**
* gst_element_set_name:
* @element: GstElement to set name of
* @name: new name of element
*
* Set the name of the element, getting rid of the old name if there was
* one.
*/
void
gst_element_set_name (GstElement *element, const gchar *name)
{
g_return_if_fail (element != NULL);
g_return_if_fail (GST_IS_ELEMENT (element));
g_return_if_fail (name != NULL);
gst_object_set_name (GST_OBJECT (element), name);
}
/**
* gst_element_get_name:
* @element: GstElement to get name of
*
* Get the name of the element.
*
* Returns: name of the element
*/
const gchar*
gst_element_get_name (GstElement *element)
{
g_return_val_if_fail (element != NULL, NULL);
g_return_val_if_fail (GST_IS_ELEMENT (element), NULL);
return GST_OBJECT_NAME (element);
}
/**
* gst_element_set_parent:
* @element: GstElement to set parent of
* @parent: new parent of the object
*
* Set the parent of the element.
*/
void
gst_element_set_parent (GstElement *element, GstObject *parent)
{
g_return_if_fail (element != NULL);
g_return_if_fail (GST_IS_ELEMENT (element));
g_return_if_fail (GST_OBJECT_PARENT (element) == NULL);
g_return_if_fail (parent != NULL);
g_return_if_fail (GTK_IS_OBJECT (parent));
g_return_if_fail ((gpointer)element != (gpointer)parent);
gst_object_set_parent (GST_OBJECT (element), parent);
}
/**
* gst_element_get_parent:
* @element: GstElement to get the parent of
*
* Get the parent of the element.
*
* Returns: parent of the element
*/
GstObject*
gst_element_get_parent (GstElement *element)
{
g_return_val_if_fail (element != NULL, NULL);
g_return_val_if_fail (GST_IS_ELEMENT (element), NULL);
return GST_OBJECT_PARENT (element);
}
/**
* gst_element_add_pad:
* @element: element to add pad to
* @pad: pad to add
*
* Add a pad (connection point) to the element, setting the parent of the
* pad to the element (and thus adding a reference).
*/
void
gst_element_add_pad (GstElement *element, GstPad *pad)
{
g_return_if_fail (element != NULL);
g_return_if_fail (GST_IS_ELEMENT (element));
g_return_if_fail (pad != NULL);
g_return_if_fail (GST_IS_PAD (pad));
// first check to make sure the pad's parent is already set
g_return_if_fail (GST_PAD_PARENT (pad) == NULL);
// then check to see if there's already a pad by that name here
g_return_if_fail (gst_object_check_uniqueness (element->pads, GST_PAD_NAME(pad)) == TRUE);
/* set the pad's parent */
GST_DEBUG (GST_CAT_ELEMENT_PADS,"setting parent of pad '%s' to '%s'\n",
GST_PAD_NAME (pad), GST_ELEMENT_NAME (element));
gst_object_set_parent (GST_OBJECT (pad), GST_OBJECT (element));
/* add it to the list */
element->pads = g_list_append (element->pads, pad);
element->numpads++;
if (gst_pad_get_direction (pad) == GST_PAD_SRC)
element->numsrcpads++;
else
element->numsinkpads++;
/* emit the NEW_PAD signal */
gtk_signal_emit (GTK_OBJECT (element), gst_element_signals[NEW_PAD], pad);
}
/**
* gst_element_remove_pad:
* @element: element to remove pad from
* @pad: pad to remove
*
* Remove a pad (connection point) from the element,
*/
void
gst_element_remove_pad (GstElement *element, GstPad *pad)
{
g_return_if_fail (element != NULL);
g_return_if_fail (GST_IS_ELEMENT (element));
g_return_if_fail (pad != NULL);
g_return_if_fail (GST_IS_PAD (pad));
g_return_if_fail (GST_PAD_PARENT (pad) == element);
/* add it to the list */
element->pads = g_list_remove (element->pads, pad);
element->numpads--;
if (gst_pad_get_direction (pad) == GST_PAD_SRC)
element->numsrcpads--;
else
element->numsinkpads--;
gtk_signal_emit (GTK_OBJECT (element), gst_element_signals[PAD_REMOVED], pad);
gst_object_unparent (GST_OBJECT (pad));
}
/**
* gst_element_add_ghost_pad:
* @element: element to add ghost pad to
* @pad: pad from which the new ghost pad will be created
* @name: name of the new ghost pad
*
* Create a ghost pad from the given pad, and add it to the list of pads
* for this element.
*/
void
gst_element_add_ghost_pad (GstElement *element, GstPad *pad, gchar *name)
{
GstPad *ghostpad;
g_return_if_fail (element != NULL);
g_return_if_fail (GST_IS_ELEMENT (element));
g_return_if_fail (pad != NULL);
g_return_if_fail (GST_IS_PAD (pad));
// then check to see if there's already a pad by that name here
g_return_if_fail (gst_object_check_uniqueness (element->pads, name) == TRUE);
GST_DEBUG(GST_CAT_ELEMENT_PADS,"creating new ghost pad called %s, from pad %s:%s\n",
name,GST_DEBUG_PAD_NAME(pad));
ghostpad = gst_ghost_pad_new (name, pad);
/* add it to the list */
GST_DEBUG(GST_CAT_ELEMENT_PADS,"adding ghost pad %s to element %s\n",
name, GST_ELEMENT_NAME (element));
element->pads = g_list_append (element->pads, ghostpad);
element->numpads++;
// set the parent of the ghostpad
gst_object_set_parent (GST_OBJECT (ghostpad), GST_OBJECT (element));
GST_DEBUG(GST_CAT_ELEMENT_PADS,"added ghostpad %s:%s\n",GST_DEBUG_PAD_NAME(ghostpad));
/* emit the NEW_GHOST_PAD signal */
gtk_signal_emit (GTK_OBJECT (element), gst_element_signals[NEW_GHOST_PAD], ghostpad);
}
/**
* gst_element_remove_ghost_pad:
* @element: element to remove the ghost pad from
* @pad: ghost pad to remove
*
* removes a ghost pad from an element
*
*/
void
gst_element_remove_ghost_pad (GstElement *element, GstPad *pad)
{
g_return_if_fail (element != NULL);
g_return_if_fail (GST_IS_ELEMENT (element));
g_return_if_fail (pad != NULL);
g_return_if_fail (GST_IS_PAD (pad));
// FIXME this is redundant?
}
/**
* gst_element_get_pad:
* @element: element to find pad of
* @name: name of pad to retrieve
*
* Retrieve a pad from the element by name.
*
* Returns: requested pad if found, otherwise NULL.
*/
GstPad*
gst_element_get_pad (GstElement *element, const gchar *name)
{
GList *walk;
g_return_val_if_fail (element != NULL, NULL);
g_return_val_if_fail (GST_IS_ELEMENT (element), NULL);
g_return_val_if_fail (name != NULL, NULL);
// if there aren't any pads, well, we're not likely to find one
if (!element->numpads)
return NULL;
// look through the list, matching by name
walk = element->pads;
while (walk) {
GstPad *pad = GST_PAD(walk->data);
if (!strcmp (GST_PAD_NAME(pad), name)) {
GST_INFO(GST_CAT_ELEMENT_PADS,"found pad %s:%s",GST_DEBUG_PAD_NAME(pad));
return pad;
}
walk = g_list_next (walk);
}
GST_INFO(GST_CAT_ELEMENT_PADS,"no such pad '%s' in element \"%s\"",name,GST_ELEMENT_NAME(element));
return NULL;
}
/**
* gst_element_get_pad_list:
* @element: element to get pads of
*
* Retrieve a list of the pads associated with the element.
*
* Returns: GList of pads
*/
GList*
gst_element_get_pad_list (GstElement *element)
{
g_return_val_if_fail (element != NULL, NULL);
g_return_val_if_fail (GST_IS_ELEMENT (element), NULL);
/* return the list of pads */
return element->pads;
}
/**
* gst_element_get_padtemplate_list:
* @element: element to get padtemplates of
*
* Retrieve a list of the padtemplates associated with the element.
*
* Returns: GList of padtemplates
*/
GList*
gst_element_get_padtemplate_list (GstElement *element)
{
GstElementClass *oclass;
g_return_val_if_fail (element != NULL, NULL);
g_return_val_if_fail (GST_IS_ELEMENT (element), NULL);
oclass = GST_ELEMENT_CLASS (GTK_OBJECT (element)->klass);
if (oclass->elementfactory == NULL) return NULL;
/* return the list of pads */
return oclass->elementfactory->padtemplates;
}
/**
* gst_element_get_padtemplate_by_name:
* @element: element to get padtemplate of
* @name: the name of the padtemplate to get.
*
* Retrieve a padtemplate from this element with the
* given name.
*
* Returns: the padtemplate with the given name
*/
GstPadTemplate*
gst_element_get_padtemplate_by_name (GstElement *element, const guchar *name)
{
GList *padlist;
g_return_val_if_fail (element != NULL, NULL);
g_return_val_if_fail (GST_IS_ELEMENT (element), NULL);
g_return_val_if_fail (name != NULL, NULL);
padlist = gst_element_get_padtemplate_list (element);
while (padlist) {
GstPadTemplate *padtempl = (GstPadTemplate*) padlist->data;
if (!strcmp (padtempl->name_template, name))
return padtempl;
padlist = g_list_next (padlist);
}
return NULL;
}
/**
* gst_element_get_padtemplate_by_compatible:
* @element: element to get padtemplate of
* @templ: a template to find a compatible template for
*
* Generate a padtemplate for this element compatible with the given
* template, ie able to link to it.
*
* Returns: the padtemplate
*/
static GstPadTemplate*
gst_element_get_padtemplate_by_compatible (GstElement *element, GstPadTemplate *compattempl)
{
GstPadTemplate *newtempl = NULL;
GList *padlist;
GST_DEBUG(GST_CAT_ELEMENT_PADS,"gst_element_get_padtemplate_by_compatible()\n");
g_return_val_if_fail (element != NULL, NULL);
g_return_val_if_fail (GST_IS_ELEMENT (element), NULL);
g_return_val_if_fail (compattempl != NULL, NULL);
padlist = gst_element_get_padtemplate_list (element);
while (padlist) {
GstPadTemplate *padtempl = (GstPadTemplate*) padlist->data;
gboolean compat = FALSE;
// Ignore name
// Ignore presence
// Check direction (must be opposite)
// Check caps
GST_DEBUG(GST_CAT_CAPS,"checking direction and caps\n");
if (padtempl->direction == GST_PAD_SRC &&
compattempl->direction == GST_PAD_SINK) {
GST_DEBUG(GST_CAT_CAPS,"compatible direction: found src pad template\n");
compat = gst_caps_check_compatibility(GST_PADTEMPLATE_CAPS (padtempl),
GST_PADTEMPLATE_CAPS (compattempl));
GST_DEBUG(GST_CAT_CAPS,"caps are %scompatible\n", (compat?"":"not "));
} else if (padtempl->direction == GST_PAD_SINK &&
compattempl->direction == GST_PAD_SRC) {
GST_DEBUG(GST_CAT_CAPS,"compatible direction: found sink pad template\n");
compat = gst_caps_check_compatibility(GST_PADTEMPLATE_CAPS (compattempl),
GST_PADTEMPLATE_CAPS (padtempl));
GST_DEBUG(GST_CAT_CAPS,"caps are %scompatible\n", (compat?"":"not "));
}
if (compat) {
newtempl = padtempl;
break;
}
padlist = g_list_next (padlist);
}
return newtempl;
}
static GstPad*
gst_element_request_pad (GstElement *element, GstPadTemplate *templ)
{
GstPad *newpad = NULL;
GstElementClass *oclass;
oclass = GST_ELEMENT_CLASS (GTK_OBJECT (element)->klass);
if (oclass->request_new_pad)
newpad = (oclass->request_new_pad)(element, templ);
return newpad;
}
/**
* gst_element_request_compatible_pad:
* @element: element to request a new pad from
* @templ: a pad template to which the new pad should be able to connect
*
* Request a new pad from the element. The template will
* be used to decide what type of pad to create. This function
* is typically used for elements with a padtemplate with presence
* GST_PAD_REQUEST.
*
* Returns: the new pad that was created.
*/
GstPad*
gst_element_request_compatible_pad (GstElement *element, GstPadTemplate *templ)
{
GstPadTemplate *templ_new;
GstPad *pad = NULL;
g_return_val_if_fail (element != NULL, NULL);
g_return_val_if_fail (GST_IS_ELEMENT (element), NULL);
g_return_val_if_fail (templ != NULL, NULL);
templ_new = gst_element_get_padtemplate_by_compatible (element, templ);
if (templ_new != NULL)
pad = gst_element_request_pad (element, templ_new);
return pad;
}
/**
* gst_element_request_pad_by_name:
* @element: element to request a new pad from
* @name: the name of the padtemplate to use.
*
* Request a new pad from the element. The name argument will
* be used to decide what padtemplate to use. This function
* is typically used for elements with a padtemplate with presence
* GST_PAD_REQUEST.
*
* Returns: the new pad that was created.
*/
GstPad*
gst_element_request_pad_by_name (GstElement *element, const gchar *name)
{
GstPadTemplate *templ;
GstPad *pad;
g_return_val_if_fail (element != NULL, NULL);
g_return_val_if_fail (GST_IS_ELEMENT (element), NULL);
g_return_val_if_fail (name != NULL, NULL);
templ = gst_element_get_padtemplate_by_name (element, name);
g_return_val_if_fail (templ != NULL, NULL);
pad = gst_element_request_pad (element, templ);
return pad;
}
/**
* gst_element_connect:
* @src: element containing source pad
* @srcpadname: name of pad in source element
* @dest: element containing destination pad
* @destpadname: name of pad in destination element
*
* Connect the two named pads of the source and destination elements.
* Side effect is that if one of the pads has no parent, it becomes a
* child of the parent of the other element. If they have different
* parents, the connection fails.
*/
void
gst_element_connect (GstElement *src, const gchar *srcpadname,
GstElement *dest, const gchar *destpadname)
{
GstPad *srcpad,*destpad;
g_return_if_fail (src != NULL);
g_return_if_fail (GST_IS_ELEMENT(src));
g_return_if_fail (srcpadname != NULL);
g_return_if_fail (dest != NULL);
g_return_if_fail (GST_IS_ELEMENT(dest));
g_return_if_fail (destpadname != NULL);
/* obtain the pads requested */
srcpad = gst_element_get_pad (src, srcpadname);
if (srcpad == NULL) {
GST_ERROR(src,"source element has no pad \"%s\"",srcpadname);
return;
}
destpad = gst_element_get_pad (dest, destpadname);
if (srcpad == NULL) {
GST_ERROR(dest,"destination element has no pad \"%s\"",destpadname);
return;
}
/* we're satisified they can be connected, let's do it */
gst_pad_connect(srcpad,destpad);
}
/**
* gst_element_disconnect:
* @src: element containing source pad
* @srcpadname: name of pad in source element
* @dest: element containing destination pad
* @destpadname: name of pad in destination element
*
* Disconnect the two named pads of the source and destination elements.
*/
void
gst_element_disconnect (GstElement *src, const gchar *srcpadname,
GstElement *dest, const gchar *destpadname)
{
GstPad *srcpad,*destpad;
g_return_if_fail (src != NULL);
g_return_if_fail (GST_IS_ELEMENT(src));
g_return_if_fail (srcpadname != NULL);
g_return_if_fail (dest != NULL);
g_return_if_fail (GST_IS_ELEMENT(dest));
g_return_if_fail (destpadname != NULL);
/* obtain the pads requested */
srcpad = gst_element_get_pad (src, srcpadname);
if (srcpad == NULL) {
GST_ERROR(src,"source element has no pad \"%s\"",srcpadname);
return;
}
destpad = gst_element_get_pad (dest, destpadname);
if (srcpad == NULL) {
GST_ERROR(dest,"destination element has no pad \"%s\"",destpadname);
return;
}
/* we're satisified they can be disconnected, let's do it */
gst_pad_disconnect(srcpad,destpad);
}
/**
* gst_element_error:
* @element: Element with the error
* @error: String describing the error
*
* This function is used internally by elements to signal an error
* condition. It results in the "error" signal.
*/
void
gst_element_error (GstElement *element, const gchar *error)
{
g_error("GstElement: error in element '%s': %s\n", GST_ELEMENT_NAME(element), error);
/* FIXME: this is not finished!!! */
gtk_signal_emit (GTK_OBJECT (element), gst_element_signals[ERROR], error);
}
/**
* gst_element_set_state:
* @element: element to change state of
* @state: new element state
*
* Sets the state of the element. This function will only set
* the elements pending state.
*
* Returns: whether or not the state was successfully set.
*/
gint
gst_element_set_state (GstElement *element, GstElementState state)
{
GstElementClass *oclass;
GstElementState curpending;
GstElementStateReturn return_val = GST_STATE_SUCCESS;
// g_print("gst_element_set_state(\"%s\",%08lx)\n",
// element->name,state);
g_return_val_if_fail (element != NULL, GST_STATE_FAILURE);
g_return_val_if_fail (GST_IS_ELEMENT (element), GST_STATE_FAILURE);
g_return_val_if_fail (element->sched != NULL, GST_STATE_FAILURE);
GST_DEBUG_ELEMENT (GST_CAT_STATES,element, "setting state from %s to %s\n",
gst_element_statename(GST_STATE(element)),
gst_element_statename(state));
/* start with the current state */
curpending = GST_STATE(element);
/* loop until the final requested state is set */
while (GST_STATE(element) != state) {
/* move the curpending state in the correct direction */
if (curpending < state) curpending<<=1;
else curpending>>=1;
/* set the pending state variable */
// FIXME: should probably check to see that we don't already have one
GST_STATE_PENDING (element) = curpending;
if (curpending != state)
GST_DEBUG_ELEMENT (GST_CAT_STATES,element,"intermediate: setting state to %s\n",
gst_element_statename(curpending));
/* call the state change function so it can set the state */
oclass = GST_ELEMENT_CLASS (GTK_OBJECT (element)->klass);
if (oclass->change_state)
return_val = (oclass->change_state)(element);
/* if that outright didn't work, we need to bail right away */
/* NOTE: this will bail on ASYNC as well! */
if (return_val == GST_STATE_FAILURE) {
GST_DEBUG_ELEMENT (GST_CAT_STATES,element,"have failed change_state return\n");
return return_val;
}
}
/* this is redundant, really, it will always return SUCCESS */
return return_val;
}
/**
* gst_element_get_factory:
* @element: element to request the factory
*
* Retrieves the factory that was used to create this element
*
* Returns: the factory used for creating this element
*/
GstElementFactory*
gst_element_get_factory (GstElement *element)
{
GstElementClass *oclass;
g_return_val_if_fail (element != NULL, NULL);
g_return_val_if_fail (GST_IS_ELEMENT (element), NULL);
oclass = GST_ELEMENT_CLASS (GTK_OBJECT (element)->klass);
return oclass->elementfactory;
}
/**
* gst_element_change_state:
* @element: element to change state of
*
* Changes the state of the element, but more importantly fires off a signal
* indicating the new state.
* The element will have no pending states anymore.
*
* Returns: whether or not the state change was successfully set.
*/
GstElementStateReturn
gst_element_change_state (GstElement *element)
{
g_return_val_if_fail (element != NULL, GST_STATE_FAILURE);
g_return_val_if_fail (GST_IS_ELEMENT (element), GST_STATE_FAILURE);
// GST_DEBUG_ELEMENT (GST_CAT_STATES, element, "default handler sets state to %s\n",
// gst_element_statename(GST_STATE_PENDING(element)));
if (GST_STATE_TRANSITION(element) == GST_STATE_PAUSED_TO_PLAYING) {
g_return_val_if_fail(GST_ELEMENT_SCHED(element), GST_STATE_FAILURE);
if (GST_ELEMENT_PARENT(element))
GST_DEBUG(GST_CAT_STATES,"PAUSED->PLAYING: element \"%s\" has parent \"%s\" and sched %p\n",
GST_ELEMENT_NAME(element),GST_ELEMENT_NAME(GST_ELEMENT_PARENT(element)),GST_ELEMENT_SCHED(element));
GST_SCHEDULE_ENABLE_ELEMENT (element->sched,element);
}
else if (GST_STATE_TRANSITION(element) == GST_STATE_PLAYING_TO_PAUSED) {
if (GST_ELEMENT_PARENT(element))
GST_DEBUG(GST_CAT_STATES,"PLAYING->PAUSED: element \"%s\" has parent \"%s\" and sched %p\n",
GST_ELEMENT_NAME(element),GST_ELEMENT_NAME(GST_ELEMENT_PARENT(element)),GST_ELEMENT_SCHED(element));
GST_SCHEDULE_DISABLE_ELEMENT (element->sched,element);
}
GST_STATE (element) = GST_STATE_PENDING (element);
GST_STATE_PENDING (element) = GST_STATE_NONE_PENDING;
// note: queues' state_change is a special case because it needs to lock
// for synchronization (from another thread). since this signal may block
// or (worse) make another state change, the queue needs to unlock before
// calling. thus, gstqueue.c::gst_queue_state_change() blocks, unblocks,
// unlocks, then emits this.
gtk_signal_emit (GTK_OBJECT (element), gst_element_signals[STATE_CHANGE],
GST_STATE (element));
return GST_STATE_SUCCESS;
}
static void
gst_element_shutdown (GtkObject *object)
{
GstElement *element = GST_ELEMENT (object);
GST_DEBUG_ELEMENT (GST_CAT_REFCOUNTING, element, "shutdown\n");
if (GST_IS_BIN (GST_OBJECT_PARENT (element)))
gst_bin_remove (GST_BIN (GST_OBJECT_PARENT (element)), element);
if (GTK_OBJECT_CLASS (parent_class)->shutdown)
GTK_OBJECT_CLASS (parent_class)->shutdown (object);
}
static void
gst_element_real_destroy (GtkObject *object)
{
GstElement *element = GST_ELEMENT (object);
GList *pads;
GstPad *pad;
GST_DEBUG_ELEMENT (GST_CAT_REFCOUNTING, element, "destroy\n");
if (element->pads) {
GList *orig;
orig = pads = g_list_copy (element->pads);
while (pads) {
pad = GST_PAD (pads->data);
//gst_object_destroy (GST_OBJECT (pad));
gst_object_ref (GST_OBJECT (pad));
gst_element_remove_pad (element, pad);
gst_object_unref (GST_OBJECT (pad));
pads = g_list_next (pads);
}
g_list_free (orig);
g_list_free (element->pads);
element->pads = NULL;
}
element->numsrcpads = 0;
element->numsinkpads = 0;
if (GTK_OBJECT_CLASS (parent_class)->destroy)
GTK_OBJECT_CLASS (parent_class)->destroy (object);
}
/*
static gchar *_gst_element_type_names[] = {
"invalid",
"none",
"char",
"uchar",
"bool",
"int",
"uint",
"long",
"ulong",
"float",
"double",
"string",
};
*/
/**
* gst_element_save_thyself:
* @element: GstElement to save
* @parent: the xml parent node
*
* Saves the element as part of the given XML structure
*
* Returns: the new xml node
*/
static xmlNodePtr
gst_element_save_thyself (GstObject *object,
xmlNodePtr parent)
{
GList *pads;
GstElementClass *oclass;
GtkType type;
GstElement *element;
g_return_val_if_fail (object != NULL, parent);
g_return_val_if_fail (GST_IS_ELEMENT (object), parent);
g_return_val_if_fail (parent != NULL, parent);
element = GST_ELEMENT (object);
oclass = GST_ELEMENT_CLASS (GTK_OBJECT (element)->klass);
xmlNewChild(parent, NULL, "name", GST_ELEMENT_NAME(element));
if (oclass->elementfactory != NULL) {
GstElementFactory *factory = (GstElementFactory *)oclass->elementfactory;
xmlNewChild (parent, NULL, "type", factory->name);
xmlNewChild (parent, NULL, "version", factory->details->version);
}
// if (element->manager)
// xmlNewChild(parent, NULL, "manager", GST_ELEMENT_NAME(element->manager));
// output all args to the element
type = GTK_OBJECT_TYPE (element);
while (type != GTK_TYPE_INVALID) {
GtkArg *args;
guint32 *flags;
guint num_args,i;
args = gtk_object_query_args (type, &flags, &num_args);
for (i=0; i<num_args; i++) {
if ((args[i].type > GTK_TYPE_NONE) &&
(flags[i] & GTK_ARG_READABLE)) {
xmlNodePtr arg;
gtk_object_getv (GTK_OBJECT (element), 1, &args[i]);
arg = xmlNewChild (parent, NULL, "arg", NULL);
xmlNewChild (arg, NULL, "name", args[i].name);
switch (args[i].type) {
case GTK_TYPE_CHAR:
xmlNewChild (arg, NULL, "value",
g_strdup_printf ("%c", GTK_VALUE_CHAR (args[i])));
break;
case GTK_TYPE_UCHAR:
xmlNewChild (arg, NULL, "value",
g_strdup_printf ("%d", GTK_VALUE_UCHAR (args[i])));
break;
case GTK_TYPE_BOOL:
xmlNewChild (arg, NULL, "value",
GTK_VALUE_BOOL (args[i]) ? "true" : "false");
break;
case GTK_TYPE_INT:
xmlNewChild (arg, NULL, "value",
g_strdup_printf ("%d", GTK_VALUE_INT (args[i])));
break;
case GTK_TYPE_LONG:
xmlNewChild (arg, NULL, "value",
g_strdup_printf ("%ld", GTK_VALUE_LONG (args[i])));
break;
case GTK_TYPE_ULONG:
xmlNewChild (arg, NULL, "value",
g_strdup_printf ("%lu", GTK_VALUE_ULONG (args[i])));
break;
case GTK_TYPE_FLOAT:
xmlNewChild (arg, NULL, "value",
g_strdup_printf ("%f", GTK_VALUE_FLOAT (args[i])));
break;
case GTK_TYPE_DOUBLE:
xmlNewChild (arg, NULL, "value",
g_strdup_printf ("%g", GTK_VALUE_DOUBLE (args[i])));
break;
case GTK_TYPE_STRING:
xmlNewChild (arg, NULL, "value", GTK_VALUE_STRING (args[i]));
break;
default:
if (args[i].type == GST_TYPE_FILENAME) {
xmlNewChild (arg, NULL, "value", GTK_VALUE_STRING (args[i]));
}
break;
}
}
}
type = gtk_type_parent (type);
}
pads = GST_ELEMENT_PADS (element);
while (pads) {
GstPad *pad = GST_PAD (pads->data);
// figure out if it's a direct pad or a ghostpad
if (GST_ELEMENT (GST_OBJECT_PARENT (pad)) == element) {
xmlNodePtr padtag = xmlNewChild (parent, NULL, "pad", NULL);
gst_object_save_thyself (GST_OBJECT (pad), padtag);
}
pads = g_list_next (pads);
}
return parent;
}
/**
* gst_element_restore_thyself:
* @self: the xml node
* @parent: the parent of this object when it's loaded
*
* Load the element from the XML description
*
* Returns: the new element
*/
GstElement*
gst_element_restore_thyself (xmlNodePtr self, GstObject *parent)
{
xmlNodePtr children = self->xmlChildrenNode;
GstElement *element;
GstObjectClass *oclass;
guchar *name = NULL;
guchar *value = NULL;
guchar *type = NULL;
// first get the needed tags to construct the element
while (children) {
if (!strcmp (children->name, "name")) {
name = g_strdup (xmlNodeGetContent (children));
} else if (!strcmp (children->name, "type")) {
type = g_strdup (xmlNodeGetContent (children));
}
children = children->next;
}
g_return_val_if_fail (name != NULL, NULL);
g_return_val_if_fail (type != NULL, NULL);
GST_INFO (GST_CAT_XML,"loading \"%s\" of type \"%s\"", name, type);
element = gst_elementfactory_make (type, name);
g_return_val_if_fail (element != NULL, NULL);
// ne need to set the parent on this object bacause the pads
// will go through the hierarchy to connect to thier peers
if (parent)
gst_object_set_parent (GST_OBJECT (element), parent);
// we have the element now, set the arguments
children = self->xmlChildrenNode;
while (children) {
if (!strcmp (children->name, "arg")) {
xmlNodePtr child = children->xmlChildrenNode;
while (child) {
if (!strcmp (child->name, "name")) {
name = g_strdup (xmlNodeGetContent (child));
}
else if (!strcmp (child->name, "value")) {
value = g_strdup (xmlNodeGetContent (child));
}
child = child->next;
}
gst_util_set_object_arg (GTK_OBJECT (element), name, value);
}
children = children->next;
}
// we have the element now, set the pads
children = self->xmlChildrenNode;
while (children) {
if (!strcmp (children->name, "pad")) {
gst_pad_load_and_connect (children, GST_OBJECT (element));
}
children = children->next;
}
oclass = GST_OBJECT_CLASS (GTK_OBJECT (element)->klass);
if (oclass->restore_thyself)
(oclass->restore_thyself) (GST_OBJECT (element), self);
if (parent)
gst_object_unparent (GST_OBJECT (element));
gst_class_signal_emit_by_name (GST_OBJECT (element), "object_loaded", self);
return element;
}
/**
* gst_element_set_sched:
* @element: Element to set manager of.
* @sched: @GstSchedule to set.
*
* Sets the scheduler of the element. For internal use only, unless you're
* writing a new bin subclass.
*/
void
gst_element_set_sched (GstElement *element,
GstSchedule *sched)
{
GST_INFO_ELEMENT (GST_CAT_PARENTAGE, element, "setting scheduler to %p",sched);
element->sched = sched;
}
/**
* gst_element_get_sched:
* @element: Element to get manager of.
*
* Returns the scheduler of the element.
*
* Returns: Element's scheduler
*/
GstSchedule*
gst_element_get_sched (GstElement *element)
{
return element->sched;
}
/**
* gst_element_set_loop_function:
* @element: Element to set loop function of.
* @loop: Pointer to loop function.
*
* This sets the loop function for the element. The function pointed to
* can deviate from the GstElementLoopFunction definition in type of
* pointer only.
*
* NOTE: in order for this to take effect, the current loop function *must*
* exit. Assuming the loop function itself is the only one who will cause
* a new loopfunc to be assigned, this should be no problem.
*/
void
gst_element_set_loop_function(GstElement *element,
GstElementLoopFunction loop)
{
/* set the loop function */
element->loopfunc = loop;
/* set the NEW_LOOPFUNC flag so everyone knows to go try again */
GST_FLAG_SET(element,GST_ELEMENT_NEW_LOOPFUNC);
}
/**
* gst_element_signal_eos:
* @element: element to trigger the eos signal of
*
* Throws the eos signal to indicate that the end of the stream is reached.
*/
void
gst_element_signal_eos (GstElement *element)
{
g_return_if_fail (element != NULL);
g_return_if_fail (GST_IS_ELEMENT (element));
gtk_signal_emit (GTK_OBJECT (element), gst_element_signals[EOS]);
GST_FLAG_SET(element,GST_ELEMENT_COTHREAD_STOPPING);
}
const gchar *gst_element_statename(int state) {
switch (state) {
#ifdef GST_DEBUG_COLOR
case GST_STATE_NONE_PENDING: return "NONE_PENDING";break;
case GST_STATE_NULL: return "\033[01;37mNULL\033[00m";break;
case GST_STATE_READY: return "\033[01;31mREADY\033[00m";break;
case GST_STATE_PLAYING: return "\033[01;32mPLAYING\033[00m";break;
case GST_STATE_PAUSED: return "\033[01;33mPAUSED\033[00m";break;
default: return "\033[01;37;41mUNKNOWN!\033[00m";
#else
case GST_STATE_NONE_PENDING: return "NONE_PENDING";break;
case GST_STATE_NULL: return "NULL";break;
case GST_STATE_READY: return "READY";break;
case GST_STATE_PLAYING: return "PLAYING";break;
case GST_STATE_PAUSED: return "PAUSED";break;
default: return "UNKNOWN!";
#endif
}
return "";
}