gstreamer/gst/gstparse.c

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/* GStreamer
* Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
* 2000 Wim Taymans <wtay@chello.be>
* 2002 Andy Wingo <wingo@pobox.com>
*
* gstparse.c: get a pipeline from a text pipeline description
*
* 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.
*/
#include <string.h>
#include "gstparse.h"
#include "gstinfo.h"
#include "gstlog.h"
#include "parse/types.h"
typedef struct _gst_parse_delayed_pad gst_parse_delayed_pad;
struct _gst_parse_delayed_pad
{
gchar *name;
GstPad *peer;
};
typedef struct
{
gchar *srcpadname;
GstPad *target_pad;
GstElement *target_element;
GstElement *pipeline;
}
dynamic_link_t;
GQuark
gst_parse_error_quark (void)
{
static GQuark quark = 0;
if (!quark)
quark = g_quark_from_static_string ("gst_parse_error");
return quark;
}
G_GNUC_UNUSED static void
dynamic_link (GstElement * element, GstPad * newpad, gpointer data)
{
dynamic_link_t *dc = (dynamic_link_t *) data;
gboolean warn = TRUE;
/* do we know the exact srcpadname? */
if (dc->srcpadname) {
GstPadTemplate *templ = gst_pad_get_pad_template (newpad);
/* see if this is the one */
if (strcmp (gst_pad_get_name (newpad), dc->srcpadname) &&
strcmp (gst_object_get_name (GST_OBJECT (templ)), dc->srcpadname)) {
return;
}
}
/* try to find a target pad if we don't know it yet */
if (!dc->target_pad) {
if (!GST_PAD_IS_LINKED (newpad)) {
dc->target_pad = gst_element_get_compatible_pad (dc->target_element, newpad);
warn = FALSE;
}
else {
return;
}
}
if (!GST_PAD_IS_LINKED (dc->target_pad) && !GST_PAD_IS_LINKED (newpad)) {
gst_element_set_state (dc->pipeline, GST_STATE_PAUSED);
if (!gst_pad_link (newpad, dc->target_pad) && warn) {
g_warning ("could not link %s:%s to %s:%s", GST_DEBUG_PAD_NAME (newpad),
GST_DEBUG_PAD_NAME (dc->target_pad));
}
gst_element_set_state (dc->pipeline, GST_STATE_PLAYING);
}
}
static gboolean
make_elements (graph_t *g, GError **error)
{
GList *l = NULL;
gchar *bin_type;
element_t *e;
if (!(g->bins || g->elements)) {
g_set_error (error,
GST_PARSE_ERROR,
GST_PARSE_ERROR_SYNTAX,
"Empty bin");
return FALSE;
}
if (g->current_bin_type)
bin_type = g->current_bin_type;
else
bin_type = "pipeline";
if (!(g->bin = gst_element_factory_make (bin_type, NULL))) {
g_set_error (error,
GST_PARSE_ERROR,
GST_PARSE_ERROR_NO_SUCH_ELEMENT,
"No such bin type %s", bin_type);
return FALSE;
}
l = g->elements;
while (l) {
e = (element_t*)l->data;
if (!(e->element = gst_element_factory_make (e->type, NULL))) {
g_set_error (error,
GST_PARSE_ERROR,
GST_PARSE_ERROR_NO_SUCH_ELEMENT,
"No such element %s", e->type);
return FALSE;
}
gst_bin_add (GST_BIN (g->bin), e->element);
l = g_list_next (l);
}
l = g->bins;
while (l) {
if (!make_elements ((graph_t*)l->data, error))
return FALSE;
gst_bin_add (GST_BIN (g->bin), ((graph_t*)l->data)->bin);
l = g_list_next (l);
}
return TRUE;
}
static gboolean
set_properties (graph_t *g, GError **error)
{
GList *l, *l2;
element_t *e;
property_t *p;
GParamSpec *pspec;
l = g->elements;
while (l) {
e = (element_t*)l->data;
l2 = e->property_values;
while (l2) {
p = (property_t*)l2->data;
if ((pspec = g_object_class_find_property (G_OBJECT_GET_CLASS (e->element), p->name))) {
g_object_set_property (G_OBJECT (e->element), p->name, p->value);
} else {
g_set_error (error,
GST_PARSE_ERROR,
GST_PARSE_ERROR_NO_SUCH_PROPERTY,
"No such property '%s' in element '%s'",
p->name, GST_OBJECT_NAME (GST_OBJECT (e->element)));
return FALSE;
}
l2 = g_list_next (l2);
}
l = g_list_next (l);
}
l = g->bins;
while (l) {
if (!set_properties ((graph_t*)l->data, error))
return FALSE;
l = g_list_next (l);
}
return TRUE;
}
static GstElement*
find_element_by_index_recurse (graph_t *g, gint i)
{
GList *l;
element_t *e;
GstElement *element;
l = g->elements;
while (l) {
e = (element_t*)l->data;
if (e->index == i) {
return e->element;
}
l = g_list_next (l);
}
l = g->bins;
while (l) {
if ((element = find_element_by_index_recurse ((graph_t*)l->data, i)))
return element;
l = g_list_next (l);
}
return NULL;
}
static GstElement*
find_element_by_index (graph_t *g, gint i)
{
while (g->parent)
g = g->parent;
return find_element_by_index_recurse (g, i);
}
static gboolean
make_links (graph_t *g, GError **error)
{
GList *l, *a, *b;
link_t *c;
dynamic_link_t *dc;
GstElement *src, *sink;
GstPad *p1, *p2;
GstPadTemplate *pt1, *pt2;
GstCaps *caps;
l = g->links;
while (l) {
c = (link_t*)l->data;
if (c->src_name) {
if (!(src = gst_bin_get_by_name (GST_BIN (g->bin), c->src_name))) {
g_set_error (error,
GST_PARSE_ERROR,
GST_PARSE_ERROR_NO_SUCH_ELEMENT,
"No such element '%s'",
c->src_name);
return FALSE;
}
} else {
src = find_element_by_index (g, c->src_index);
g_assert (src);
}
if (c->sink_name) {
if (!(sink = gst_bin_get_by_name (GST_BIN (g->bin), c->sink_name))) {
g_set_error (error,
GST_PARSE_ERROR,
GST_PARSE_ERROR_NO_SUCH_ELEMENT,
"No such element '%s'",
c->sink_name);
return FALSE;
}
} else {
sink = find_element_by_index (g, c->sink_index);
g_assert (sink);
}
a = c->src_pads;
b = c->sink_pads;
caps = c->caps;
gst_caps_debug (caps, "foo");
/* g_print ("a: %p, b: %p\n", a, b); */
if (a && b) {
/* balanced multipad link */
while (a && b) {
p1 = gst_element_get_pad (src, (gchar*)a->data);
p2 = gst_element_get_pad (sink, (gchar*)b->data);
if (!p2)
goto could_not_get_pad_b;
if (!p1 && p2 && (pt1 = gst_element_get_pad_template (src, (gchar*)a->data)) &&
pt1->presence == GST_PAD_SOMETIMES) {
dc = g_new0 (dynamic_link_t, 1);
dc->srcpadname = (gchar*)a->data;
dc->target_pad = p2;
dc->target_element = sink;
dc->pipeline = g->bin;
GST_DEBUG (GST_CAT_PIPELINE, "setting up dynamic link %s:%s and %s:%s",
GST_OBJECT_NAME (GST_OBJECT (src)),
(gchar*)a->data, GST_DEBUG_PAD_NAME (p2));
g_signal_connect (G_OBJECT (src), "new_pad", G_CALLBACK (dynamic_link), dc);
} else if (!p1) {
goto could_not_get_pad_a;
} else if (!gst_pad_link_filtered (p1, p2, caps)) {
goto could_not_link_pads;
}
a = g_list_next (a);
b = g_list_next (b);
}
} else if (a) {
if ((pt1 = gst_element_get_pad_template (src, (gchar*)a->data))) {
if ((p1 = gst_element_get_pad (src, (gchar*)a->data)) || pt1->presence == GST_PAD_SOMETIMES) {
if (!p1) {
/* sigh, a hack until i fix the gstelement api... */
if ((pt2 = gst_element_get_compatible_pad_template (sink, pt1))) {
if ((p2 = gst_element_get_pad (sink, pt2->name_template))) {
dc = g_new0 (dynamic_link_t, 1);
dc->srcpadname = (gchar*)a->data;
dc->target_pad = p2;
dc->target_element = NULL;
dc->pipeline = g->bin;
GST_DEBUG (GST_CAT_PIPELINE, "setting up dynamic link %s:%s and %s:%s",
GST_OBJECT_NAME (GST_OBJECT (src)),
(gchar*)a->data, GST_DEBUG_PAD_NAME (p2));
g_signal_connect (G_OBJECT (src), "new_pad", G_CALLBACK (dynamic_link), dc);
goto next;
} else {
/* both pt1 and pt2 are sometimes templates. sheesh. */
goto both_templates_have_sometimes_presence;
}
} else {
/* if the target pad has no padtemplate we will figure out a target
* pad later on */
dc = g_new0 (dynamic_link_t, 1);
dc->srcpadname = (gchar*)a->data;
dc->target_pad = NULL;
dc->target_element = sink;
dc->pipeline = g->bin;
GST_DEBUG (GST_CAT_PIPELINE, "setting up dynamic link %s:%s, and some pad in %s",
GST_OBJECT_NAME (GST_OBJECT (src)),
(gchar*)a->data, GST_OBJECT_NAME (sink));
g_signal_connect (G_OBJECT (src), "new_pad", G_CALLBACK (dynamic_link), dc);
goto next;
}
} else {
goto could_not_get_compatible_to_a;
}
} else {
goto could_not_get_pad_a;
}
} else {
goto could_not_get_pad_a;
}
if (!gst_pad_link_filtered (p1, p2, caps)) {
goto could_not_link_pads;
}
} else if (b) {
/* we don't support dynamic links on this side yet, if ever */
if (!(p2 = gst_element_get_pad (sink, (gchar*)b->data))) {
goto could_not_get_pad_b;
}
if (!(p1 = gst_element_get_compatible_pad (src, p2))) {
goto could_not_get_compatible_to_b;
}
if (!gst_pad_link_filtered (p1, p2, caps)) {
goto could_not_link_pads;
}
} else {
if (!gst_element_link_filtered (src, sink, caps)) {
goto could_not_link_elements;
}
}
next:
l = g_list_next (l);
}
l = g->bins;
while (l) {
if (!make_links ((graph_t*)l->data, error))
return FALSE;
l = g_list_next (l);
}
return TRUE;
could_not_get_pad_a:
g_set_error (error,
GST_PARSE_ERROR,
GST_PARSE_ERROR_LINK,
"Could not get a pad %s from element %s",
(gchar*)a->data, GST_OBJECT_NAME (src));
return FALSE;
could_not_get_pad_b:
g_set_error (error,
GST_PARSE_ERROR,
GST_PARSE_ERROR_LINK,
"Could not get a pad %s from element %s",
(gchar*)b->data, GST_OBJECT_NAME (sink));
return FALSE;
could_not_get_compatible_to_a:
g_set_error (error,
GST_PARSE_ERROR,
GST_PARSE_ERROR_LINK,
"Could not find a compatible pad in element %s to for %s:%s",
GST_OBJECT_NAME (sink), GST_OBJECT_NAME (src), (gchar*)a->data);
return FALSE;
could_not_get_compatible_to_b:
g_set_error (error,
GST_PARSE_ERROR,
GST_PARSE_ERROR_LINK,
"Could not find a compatible pad in element %s to for %s:%s",
GST_OBJECT_NAME (src), GST_OBJECT_NAME (sink), (gchar*)b->data);
return FALSE;
both_templates_have_sometimes_presence:
g_set_error (error,
GST_PARSE_ERROR,
GST_PARSE_ERROR_LINK,
"Both %s:%s and %s:%s have GST_PAD_SOMETIMES presence, operation not supported",
GST_OBJECT_NAME (src), pt1->name_template, GST_OBJECT_NAME (sink), pt2->name_template);
return FALSE;
could_not_link_pads:
g_set_error (error,
GST_PARSE_ERROR,
GST_PARSE_ERROR_LINK,
"Could not link %s:%s to %s:%s",
GST_DEBUG_PAD_NAME (p1),
GST_DEBUG_PAD_NAME (p2));
return FALSE;
could_not_link_elements:
g_set_error (error,
GST_PARSE_ERROR,
GST_PARSE_ERROR_LINK,
"Could not link element %s to %s",
GST_OBJECT_NAME (src),
GST_OBJECT_NAME (sink));
return FALSE;
}
static GstBin*
pipeline_from_graph (graph_t *g, GError **error)
{
if (!make_elements (g, error))
return NULL;
if (!set_properties (g, error))
return NULL;
if (!make_links (g, error))
return NULL;
return (GstBin*)g->bin;
}
/**
* gst_parse_launchv:
* @argv: null-terminated array of arguments
* @error: pointer to GError
*
* Create a new pipeline based on command line syntax.
*
* Returns: a new pipeline on success, NULL on failure and error
* will contain the error message.
*/
GstBin *
gst_parse_launchv (const gchar **argv, GError **error)
{
GstBin *pipeline;
GString *str;
const gchar **argvp, *arg;
gchar *tmp;
g_return_val_if_fail (argv != NULL, NULL);
/* let's give it a nice size. */
str = g_string_sized_new (1024);
argvp = argv;
while (*argvp) {
arg = *argvp;
tmp = _gst_parse_escape (arg);
g_string_append (str, tmp);
g_free (tmp);
g_string_append (str, " ");
argvp++;
}
pipeline = gst_parse_launch (str->str, error);
g_string_free (str, TRUE);
return pipeline;
}
gchar *_gst_parse_escape (const gchar *str)
{
GString *gstr = NULL;
g_return_val_if_fail (str != NULL, NULL);
gstr = g_string_sized_new (strlen (str));
while (*str) {
if (*str == ' ')
g_string_append_c (gstr, '\\');
g_string_append_c (gstr, *str);
str++;
}
return gstr->str;
}
void _gst_parse_unescape (gchar *str)
{
gchar *walk;
g_return_if_fail (str != NULL);
walk = str;
while (*walk) {
if (*walk == '\\')
walk++;
*str = *walk;
str++;
walk++;
}
*str = '\0';
}
/**
* gst_parse_launch:
* @pipeline_description: the command line describing the pipeline
* @error: the error message in case of a failure
*
* Create a new pipeline based on command line syntax.
*
* Returns: a new bin on success, NULL on failure. By default the bin is
* a GstPipeline, but it depends on the pipeline_description.
*/
GstBin *
gst_parse_launch (const gchar * pipeline_description, GError **error)
{
graph_t *graph;
static GStaticMutex flex_lock = G_STATIC_MUTEX_INIT;
g_return_val_if_fail (pipeline_description != NULL, NULL);
GST_INFO (GST_CAT_PIPELINE, "parsing pipeline description %s",
pipeline_description);
/* the need for the mutex will go away with flex 2.5.6 */
g_static_mutex_lock (&flex_lock);
graph = _gst_parse_launch (pipeline_description, error);
g_static_mutex_unlock (&flex_lock);
if (!graph)
return NULL;
return pipeline_from_graph (graph, error);
}