gstreamer/gst/autoplug/gstspider.c
David Schleef 8c9cd079d4 Merge CAPS branch
Original commit message from CVS:
Merge CAPS branch
2003-12-22 01:39:35 +00:00

678 lines
22 KiB
C

/* GStreamer
* Copyright (C) 2002 Erik Walthinsen <omega@cse.ogi.edu>
* 2002 Wim Taymans <wtay@chello.be>
*
* gstspider.c: element to automatically link sinks and sources
*
* 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.
*/
/*
* TODO:
* - handle automatic removal of unneeded elements
* - make the spider handle and send events (esp. new media)
* - decide if we plug pads or elements, currently it's a mess
* - allow unlinking
* - implement proper saving/loading from xml
* - implement a way to allow merging/splitting (aka tee)
* - find ways to define which elements to use when plugging
* - remove pads
* - improve typefinding
* - react to errors inside the pipeline
* - implement more properties, change the current
* - emit signals (most important: "NOT PLUGGABLE")
* - implement something for reporting the state of the spider
* to allow easier debugging.
* (could be useful for bins in general)
* - fix bugs
* ...
*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include "gstspider.h"
#include "gstspideridentity.h"
#include "gstsearchfuncs.h"
GST_DEBUG_CATEGORY (gst_spider_debug);
#define GST_CAT_DEFAULT gst_spider_debug
/* signals and args */
enum {
/* FILL ME */
LAST_SIGNAL
};
enum {
ARG_0,
ARG_FACTORIES,
/* FILL ME TOO */
};
/* generic templates */
static GstStaticPadTemplate spider_src_factory =
GST_STATIC_PAD_TEMPLATE (
"src_%d",
GST_PAD_SRC,
GST_PAD_REQUEST,
GST_STATIC_CAPS_ANY
);
/* standard GObject stuff */
static void gst_spider_class_init (GstSpiderClass *klass);
static void gst_spider_init (GstSpider *spider);
static void gst_spider_dispose (GObject *object);
/* element class functions */
static GstPad* gst_spider_request_new_pad (GstElement *element, GstPadTemplate *templ, const gchar *name);
static void gst_spider_set_property (GObject *object, guint prop_id, const GValue *value, GParamSpec *pspec);
static void gst_spider_get_property (GObject *object, guint prop_id, GValue *value, GParamSpec *pspec);
/* link functions */
static GstSpiderConnection * gst_spider_link_new (GstSpiderIdentity *src);
static void gst_spider_link_destroy (GstSpiderConnection *conn);
static void gst_spider_link_reset (GstSpiderConnection *conn, GstElement *to);
static void gst_spider_link_add (GstSpiderConnection *conn, GstElement *element);
static GstSpiderConnection * gst_spider_link_find (GstSpiderIdentity *src);
static GstSpiderConnection * gst_spider_link_get (GstSpiderIdentity *src);
/* autoplugging functions */
static GstElement * gst_spider_find_element_to_plug (GstElement *src, GstElementFactory *fac, GstPadDirection dir);
static GstPadLinkReturn gst_spider_plug (GstSpiderConnection *conn);
static GstPadLinkReturn gst_spider_plug_from_srcpad (GstSpiderConnection *conn, GstPad *srcpad);
/*static GstPadLinkReturn gst_spider_plug_peers (GstSpider *spider, GstPad *srcpad, GstPad *sinkpad); */
static GstPadLinkReturn gst_spider_create_and_plug (GstSpiderConnection *conn, GList *plugpath);
/* random functions */
static gchar * gst_spider_unused_elementname (GstBin *bin, const gchar *startwith);
/* debugging stuff
static void print_spider_contents (GstSpider *spider);
static void print_spider_link (GstSpiderConnection *conn); */
/* === variables === */
static GstElementClass * parent_class = NULL;
/* no signals yet
static guint gst_spider_signals[LAST_SIGNAL] = { 0 };*/
/* GObject and GStreamer init functions */
GType
gst_spider_get_type(void)
{
static GType spider_type = 0;
if (!spider_type) {
static const GTypeInfo spider_info = {
sizeof(GstSpiderClass),
NULL,
NULL,
(GClassInitFunc) gst_spider_class_init,
NULL,
NULL,
sizeof(GstSpider),
0,
(GInstanceInitFunc)gst_spider_init,
};
spider_type = g_type_register_static (GST_TYPE_BIN, "GstSpider", &spider_info, 0);
}
return spider_type;
}
static void
gst_spider_class_init (GstSpiderClass *klass)
{
GObjectClass *gobject_class;
GstElementClass *gstelement_class;
gobject_class = (GObjectClass*) klass;
gstelement_class = (GstElementClass*) klass;
parent_class = g_type_class_ref(GST_TYPE_BIN);
/* properties */
g_object_class_install_property (G_OBJECT_CLASS (klass), ARG_FACTORIES,
g_param_spec_pointer ("factories", "allowed factories", "allowed factories for autoplugging", G_PARAM_READWRITE));
gobject_class->set_property = gst_spider_set_property;
gobject_class->get_property = gst_spider_get_property;
gobject_class->dispose = gst_spider_dispose;
gst_element_class_add_pad_template (gstelement_class,
gst_static_pad_template_get (&spider_src_factory));
gst_element_class_set_details (gstelement_class, &gst_spider_details);
gstelement_class->request_new_pad = GST_DEBUG_FUNCPTR(gst_spider_request_new_pad);
}
static void
gst_spider_init (GstSpider *spider)
{
/* use only elements which have sources and sinks and where the sinks have caps */
/* FIXME: How do we handle factories that are added after the spider was constructed? */
spider->factories = gst_autoplug_factories_filters_with_sink_caps ((GList *)
gst_registry_pool_feature_list (GST_TYPE_ELEMENT_FACTORY));
spider->links = NULL;
spider->sink_ident = gst_spider_identity_new_sink ("sink_ident");
gst_bin_add (GST_BIN (spider), GST_ELEMENT (spider->sink_ident));
gst_element_add_ghost_pad (GST_ELEMENT(spider), spider->sink_ident->sink, "sink");
}
static void
gst_spider_dispose (GObject *object)
{
GstSpider *spider;
spider = GST_SPIDER (object);
g_list_free (spider->factories);
((GObjectClass *) parent_class)->dispose (object);
}
static GstPad *
gst_spider_request_new_pad (GstElement *element, GstPadTemplate *templ, const gchar *name)
{
GstPad *returnpad;
gchar *padname;
GstSpiderIdentity *identity;
GstSpider *spider;
g_return_val_if_fail (templ != NULL, NULL);
g_return_val_if_fail (GST_IS_PAD_TEMPLATE (templ), NULL);
g_return_val_if_fail (GST_PAD_TEMPLATE_DIRECTION (templ) == GST_PAD_SRC, NULL);
spider = GST_SPIDER (element);
/* create an identity object, so we have a pad */
padname = gst_spider_unused_elementname ((GstBin *)spider, "src_");
identity = gst_spider_identity_new_src (padname);
returnpad = identity->src;
/* FIXME: use the requested name for the pad */
gst_object_replace ((GstObject **) &returnpad->padtemplate, (GstObject *) templ);
gst_bin_add (GST_BIN (element), GST_ELEMENT (identity));
returnpad = gst_element_add_ghost_pad (element, returnpad, padname);
gst_spider_link_new (identity);
GST_DEBUG ("successuflly created requested pad %s:%s", GST_DEBUG_PAD_NAME (returnpad));
return returnpad;
}
static void
gst_spider_set_property (GObject *object, guint prop_id, const GValue *value, GParamSpec *pspec)
{
GstSpider *spider;
GList *list;
/* it's not null if we got it, but it might not be ours */
g_return_if_fail (GST_IS_SPIDER (object));
spider = GST_SPIDER (object);
switch (prop_id) {
case ARG_FACTORIES:
list = (GList *) g_value_get_pointer (value);
while (list)
{
g_return_if_fail (list->data != NULL);
g_return_if_fail (GST_IS_ELEMENT_FACTORY (list->data));
list = g_list_next (list);
}
g_list_free (spider->factories);
spider->factories = (GList *) g_value_get_pointer (value);
break;
default:
break;
}
}
static void
gst_spider_get_property (GObject *object, guint prop_id, GValue *value, GParamSpec *pspec)
{
GstSpider *spider;
/* it's not null if we got it, but it might not be ours */
spider = GST_SPIDER(object);
switch (prop_id) {
case ARG_FACTORIES:
g_value_set_pointer (value, spider->factories);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
/* get a name for an element that isn't used yet */
static gchar *
gst_spider_unused_elementname (GstBin *bin, const gchar *startwith)
{
gchar * name = g_strdup_printf ("%s%d", startwith, 0);
guint i;
for (i = 0; gst_bin_get_by_name (bin, name) != NULL; )
{
g_free (name);
name = g_strdup_printf ("%s%d", startwith, ++i);
}
return name;
}
static void
gst_spider_link_sometimes (GstElement *src, GstPad *pad, GstSpiderConnection *conn)
{
gulong signal_id = conn->signal_id;
/* try to autoplug the elements */
if (gst_spider_plug_from_srcpad (conn, pad) != GST_PAD_LINK_REFUSED) {
GST_DEBUG ("%s:%s was autoplugged to %s:%s, removing callback",
GST_DEBUG_PAD_NAME (pad), GST_DEBUG_PAD_NAME (conn->src->sink));
g_signal_handler_disconnect (src, signal_id);
signal_id = 0;
}
}
/* create a new link from those two elements */
static GstSpiderConnection *
gst_spider_link_new (GstSpiderIdentity *src)
{
GstSpider *spider = GST_SPIDER (GST_OBJECT_PARENT (src));
GstSpiderConnection *conn = g_new0 (GstSpiderConnection, 1);
conn->src = src;
conn->path = NULL;
conn->current = (GstElement *) spider->sink_ident;
spider->links = g_list_prepend (spider->links, conn);
return conn;
}
static void
gst_spider_link_destroy (GstSpiderConnection *conn)
{
GstSpider *spider = GST_SPIDER (GST_OBJECT_PARENT (conn->src));
/* reset link to unplugged */
gst_spider_link_reset (conn, (GstElement *) spider->sink_ident);
g_free (conn);
}
static void
gst_spider_link_reset (GstSpiderConnection *conn, GstElement *to)
{
GstSpider *spider = GST_SPIDER (GST_OBJECT_PARENT (conn->src));
GST_DEBUG ("resetting link from %s to %s, currently at %s to %s", GST_ELEMENT_NAME (spider->sink_ident),
GST_ELEMENT_NAME (conn->src), GST_ELEMENT_NAME (conn->current), GST_ELEMENT_NAME (to));
while ((conn->path != NULL) && ((GstElement *) conn->path->data != to))
{
gst_object_unref ((GstObject *) conn->path->data);
conn->path = g_list_delete_link (conn->path, conn->path);
}
if (conn->path == NULL)
{
conn->current = (GstElement *) spider->sink_ident;
} else {
conn->current = to;
}
}
/* add an element to the link */
static void
gst_spider_link_add (GstSpiderConnection *conn, GstElement *element)
{
gst_object_ref ((GstObject *) element);
gst_object_sink ((GstObject *) element);
conn->path = g_list_prepend (conn->path, element);
conn->current = element;
}
/* find the link from those two elements */
static GstSpiderConnection *
gst_spider_link_find (GstSpiderIdentity *src)
{
GstSpider *spider = (GstSpider *) GST_OBJECT_PARENT (src);
GList *list = spider->links;
while (list)
{
GstSpiderConnection *conn = (GstSpiderConnection *) list->data;
if (conn->src == src){
return conn;
}
list = g_list_next(list);
}
return NULL;
}
/* get a new link from those two elements
* search first; if none is found, create a new one */
static GstSpiderConnection *
gst_spider_link_get (GstSpiderIdentity *src)
{
GstSpiderConnection *ret;
if ((ret = gst_spider_link_find (src)) != NULL)
{
return ret;
}
return gst_spider_link_new (src);
}
void
gst_spider_identity_plug (GstSpiderIdentity *ident)
{
GstSpider *spider;
const GList *padlist;
GstPadDirection dir;
GstSpiderConnection *conn;
/* checks */
g_return_if_fail (ident != NULL);
g_return_if_fail (GST_IS_SPIDER_IDENTITY (ident));
spider = GST_SPIDER (GST_ELEMENT_PARENT (ident));
g_assert (spider != NULL);
g_assert (GST_IS_SPIDER (spider));
/* return if we're already plugged */
if (ident->plugged) return;
/* get the direction of our ident */
if (GST_PAD_PEER (ident->sink))
{
if (GST_PAD_PEER (ident->src))
{
/* Hey, the ident is linked on both sides */
g_warning ("Trying to autoplug a linked element. Aborting...");
return;
} else {
dir = GST_PAD_SINK;
}
} else {
if (GST_PAD_PEER (ident->src))
{
dir = GST_PAD_SRC;
} else {
/* the ident isn't linked on either side */
g_warning ("Trying to autoplug an unlinked element. Aborting...");
return;
}
}
/* now iterate all possible pads and link when needed */
padlist = gst_element_get_pad_list (GST_ELEMENT (spider));
while (padlist)
{
GstPad *otherpad;
GstSpiderIdentity *peer;
g_assert (GST_IS_PAD (padlist->data));
otherpad = (GstPad *) GST_GPAD_REALPAD (padlist->data);
peer = (GstSpiderIdentity *) GST_PAD_PARENT (otherpad);
/* we only want to link to the other side */
if (dir != GST_PAD_DIRECTION (otherpad))
{
/* we only link to plugged in elements */
if (peer->plugged == TRUE)
{
/* plug in the right direction */
if (dir == GST_PAD_SINK)
{
conn = gst_spider_link_get (peer);
} else {
conn = gst_spider_link_get (ident);
}
if ((GstElement *) spider->sink_ident == conn->current)
{
gst_spider_plug (conn);
}
}
}
padlist = g_list_next (padlist);
}
ident->plugged = TRUE;
}
void
gst_spider_identity_unplug (GstSpiderIdentity *ident)
{
GstSpider *spider = (GstSpider *) GST_OBJECT_PARENT (ident);
GList *list = spider->links;
while (list)
{
GstSpiderConnection *conn = list->data;
GList *cur = list;
list = g_list_next (list);
if (conn->src == ident)
{
g_list_delete_link (spider->links, cur);
gst_spider_link_destroy (conn);
}
}
ident->plugged = FALSE;
}
/* links src to sink using the elementfactories in plugpath
* plugpath will be removed afterwards */
static GstPadLinkReturn
gst_spider_create_and_plug (GstSpiderConnection *conn, GList *plugpath)
{
GstSpider *spider = (GstSpider *) GST_OBJECT_PARENT (conn->src);
GList *endelements = NULL, *templist = NULL;
GstElement *element;
/* exit if plugging is already done */
if ((GstElement *) conn->src == conn->current)
return GST_PAD_LINK_DONE;
/* try to shorten the list at the end and not duplicate link code */
if (plugpath != NULL)
{
templist = g_list_last (plugpath);
element = (GstElement *) conn->src;
while ((plugpath != NULL) && (element = gst_spider_find_element_to_plug (element, (GstElementFactory *) plugpath->data, GST_PAD_SINK)))
{
GList *cur = templist;
endelements = g_list_prepend (endelements, element);
templist = g_list_previous (templist);
g_list_delete_link (cur, cur);
}
}
/* do the linking */
while (conn->current != (GstElement *) (endelements == NULL ? conn->src : endelements->data))
{
/* get sink element to plug, src is conn->current */
if (plugpath == NULL)
{
element = (GstElement *) (endelements == NULL ? conn->src : endelements->data);
} else {
element = gst_element_factory_create ((GstElementFactory *) plugpath->data, NULL);
GST_DEBUG ("Adding element %s of type %s and syncing state with autoplugger",
GST_ELEMENT_NAME (element), GST_PLUGIN_FEATURE_NAME (plugpath->data));
gst_bin_add (GST_BIN (spider), element);
}
/* insert and link new element */
if (gst_element_link (conn->current, element)) {
gst_element_sync_state_with_parent (element);
} else {
/* check if the src has SOMETIMES templates. If so, link a callback */
GList *templs = gst_element_get_pad_template_list (conn->current);
/* remove element that couldn't be linked, if it wasn't the endpoint */
if (element != (GstElement *) conn->src)
gst_bin_remove (GST_BIN (spider), element);
while (templs) {
GstPadTemplate *templ = (GstPadTemplate *) templs->data;
if ((GST_PAD_TEMPLATE_DIRECTION (templ) == GST_PAD_SRC) && (GST_PAD_TEMPLATE_PRESENCE(templ) == GST_PAD_SOMETIMES))
{
GST_DEBUG ("adding callback to link element %s to %s", GST_ELEMENT_NAME (conn->current), GST_ELEMENT_NAME (conn->src));
conn->signal_id = g_signal_connect (G_OBJECT (conn->current), "new_pad",
G_CALLBACK (gst_spider_link_sometimes), conn);
g_list_free (plugpath);
return GST_PAD_LINK_DELAYED;
}
templs = g_list_next (templs);
}
GST_DEBUG ("no chance to link element %s to %s", GST_ELEMENT_NAME (conn->current), GST_ELEMENT_NAME (conn->src));
g_list_free (plugpath);
return GST_PAD_LINK_REFUSED;
}
GST_DEBUG ("added element %s and attached it to element %s", GST_ELEMENT_NAME (element), GST_ELEMENT_NAME (conn->current));
gst_spider_link_add (conn, element);
if (plugpath != NULL)
plugpath = g_list_delete_link (plugpath, plugpath);
}
/* ref all elements at the end */
while (endelements)
{
gst_spider_link_add (conn, endelements->data);
endelements = g_list_delete_link (endelements, endelements);
}
return GST_PAD_LINK_DONE;
}
/* checks, if src is already linked to an element from factory fac on direction dir */
static GstElement *
gst_spider_find_element_to_plug (GstElement *src, GstElementFactory *fac, GstPadDirection dir)
{
GList *padlist = GST_ELEMENT_PADS (src);
while (padlist)
{
GstPad *pad = (GstPad *) GST_PAD_REALIZE (padlist->data);
/* is the pad on the right side and is it linked? */
if ((GST_PAD_DIRECTION (pad) == dir) && (pad = (GstPad *) (GST_RPAD_PEER (pad))))
{
/* is the element the pad is linked to of the right type? */
GstElement *element = GST_PAD_PARENT (pad);
if (G_TYPE_FROM_INSTANCE (element) == gst_element_factory_get_element_type (fac)) {
return element;
}
}
padlist = g_list_next (padlist);
}
return NULL;
}
/* try to establish the link */
static GstPadLinkReturn
gst_spider_plug (GstSpiderConnection *conn)
{
GstSpider *spider = (GstSpider *) GST_OBJECT_PARENT (conn->src);
if ((GstElement *) conn->src == conn->current)
return GST_PAD_LINK_DONE;
if ((GstElement *) spider->sink_ident == conn->current)
return gst_spider_plug_from_srcpad (conn, spider->sink_ident->src);
g_warning ("FIXME: autoplugging only possible from GstSpiderIdentity conn->sink yet (yep, that's technical)\n");
return GST_PAD_LINK_REFUSED;
}
/* try to establish the link using this pad */
static GstPadLinkReturn
gst_spider_plug_from_srcpad (GstSpiderConnection *conn, GstPad *srcpad)
{
GstElement *element;
GList *plugpath;
gboolean result = TRUE;
GstSpider *spider = (GstSpider *) GST_OBJECT_PARENT (conn->src);
GstElement *startelement = conn->current;
g_assert ((GstElement *) GST_OBJECT_PARENT (srcpad) == conn->current);
GST_DEBUG ("trying to plug from %s:%s to %s",
GST_DEBUG_PAD_NAME (srcpad), GST_ELEMENT_NAME (conn->src));
/* see if they match already */
if (gst_pad_link (srcpad, conn->src->sink)) {
GST_DEBUG ("%s:%s and %s:%s can link directly",
GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (conn->src->sink));
gst_pad_unlink (srcpad, conn->src->sink);
gst_spider_create_and_plug (conn, NULL);
return GST_PAD_LINK_OK;
}
/* find a path from src to sink */
plugpath = gst_autoplug_sp (gst_pad_get_caps (srcpad), gst_pad_get_caps (conn->src->sink), spider->factories);
/* prints out the path that was found for plugging */
/* g_print ("found path from %s to %s:\n", GST_ELEMENT_NAME (conn->current), GST_ELEMENT_NAME (conn->src));
templist = plugpath;
while (templist)
{
g_print("%s\n", GST_OBJECT_NAME (templist->data));
templist = g_list_next (templist);
}*/
/* if there is no way to plug: return */
if (plugpath == NULL) {
GST_DEBUG ("no chance to plug from %s to %s", GST_ELEMENT_NAME (conn->current), GST_ELEMENT_NAME (conn->src));
return GST_PAD_LINK_REFUSED;
}
GST_DEBUG ("found a link that needs %d elements", g_list_length (plugpath));
/* now remove non-needed elements from the beginning of the path
* alter src to point to the new element where we need to start
* plugging and alter the plugpath to represent the elements, that must be plugged
*/
element = conn->current;
while ((plugpath != NULL) && (element = gst_spider_find_element_to_plug (element, (GstElementFactory *) plugpath->data, GST_PAD_SRC)))
{
gst_spider_link_add (conn, element);
plugpath = g_list_delete_link (plugpath, plugpath);
}
GST_DEBUG ("%d elements must be inserted to establish the link", g_list_length (plugpath));
/* create the elements and plug them */
result = gst_spider_create_and_plug (conn, plugpath);
/* reset the "current" element */
if (result == GST_PAD_LINK_REFUSED)
{
gst_spider_link_reset (conn, startelement);
}
return result;
}
GstElementDetails gst_spider_details = GST_ELEMENT_DETAILS (
"Spider",
"Generic",
"Automatically link sinks and sources",
"Benjamin Otte <in7y118@public.uni-hamburg.de>"
);
static gboolean
plugin_init (GstPlugin *plugin)
{
GST_DEBUG_CATEGORY_INIT (gst_spider_debug, "spider", 0, "spider autoplugging element");
if (!gst_element_register (plugin, "spider", GST_RANK_SECONDARY, GST_TYPE_SPIDER))
return FALSE;
if (!gst_element_register (plugin, "spideridentity", GST_RANK_NONE, GST_TYPE_SPIDER_IDENTITY))
return FALSE;
return TRUE;
}
GST_PLUGIN_DEFINE (
GST_VERSION_MAJOR,
GST_VERSION_MINOR,
"gstspider",
"a 1:n autoplugger",
plugin_init,
VERSION,
GST_LICENSE,
GST_PACKAGE,
GST_ORIGIN
)