Files
clapper/lib/gst/plugin/gstclapperimporterloader.c
Rafostar 044710f97e plugin: Add clapper GStreamer plugin
Add new GStreamer plugin with custom video sink for Clapper video player.

The main difference is that unlike the old one, this does not operate using `GtkGLArea`
anymore, but processes and displays `GdkTextures` directly through `GtkPicture` widget.
Also this one is installed like any other GStreamer plugin, thus can be used via
`gst-launch-1.0` binary or even by other GTK4 apps if they wish to integrate it.

In order to not depend on GL stuff at build time, this plugin uses seperate GModules
called "importers" in order to import different kind of memories into GdkTexture. This
allows expanding its capabilities further then we were able to do before.
2022-05-05 11:16:34 +02:00

417 lines
10 KiB
C
Vendored

/*
* Copyright (C) 2022 Rafał Dzięgiel <rafostar.github@gmail.com>
*
* 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., 51 Franklin St, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <gmodule.h>
#include "gstclapperimporterloader.h"
#include "gstclapperimporter.h"
#define GST_CAT_DEFAULT gst_clapper_importer_loader_debug
GST_DEBUG_CATEGORY_STATIC (GST_CAT_DEFAULT);
typedef GstClapperImporter* (* MakeImporter) (void);
typedef GstCaps* (* MakeCaps) (GstRank *rank, GStrv *context_types);
typedef struct
{
gchar *module_path;
GModule *open_module;
GstCaps *caps;
GstRank rank;
GStrv context_types;
} GstClapperImporterData;
static void
gst_clapper_importer_data_free (GstClapperImporterData *data)
{
g_free (data->module_path);
if (data->open_module)
g_module_close (data->open_module);
gst_clear_caps (&data->caps);
g_strfreev (data->context_types);
g_free (data);
}
static gboolean
_open_importer (GstClapperImporterData *data)
{
g_return_val_if_fail (data && data->module_path, FALSE);
/* Already open */
if (data->open_module)
return TRUE;
GST_DEBUG ("Opening module: %s", data->module_path);
data->open_module = g_module_open (data->module_path, G_MODULE_BIND_LAZY);
if (!data->open_module) {
GST_WARNING ("Could not load importer: %s, reason: %s",
data->module_path, g_module_error ());
return FALSE;
}
GST_DEBUG ("Opened importer module");
/* Make sure module stays loaded. Seems to be needed for
* reusing exported symbols from the same module again */
g_module_make_resident (data->open_module);
return TRUE;
}
static void
_close_importer (GstClapperImporterData *data)
{
if (!data || !data->open_module)
return;
if (G_LIKELY (g_module_close (data->open_module)))
GST_DEBUG ("Closed module: %s", data->module_path);
else
GST_WARNING ("Could not close importer module");
data->open_module = NULL;
}
static GstClapperImporter *
_obtain_importer_internal (GstClapperImporterData *data)
{
MakeImporter make_importer;
GstClapperImporter *importer = NULL;
if (!_open_importer (data))
goto finish;
if (!g_module_symbol (data->open_module, "make_importer", (gpointer *) &make_importer)
|| make_importer == NULL) {
GST_WARNING ("Make function missing in importer");
goto fail;
}
/* Do not close the module, we are gonna continue using it */
if ((importer = make_importer ()))
goto finish;
fail:
_close_importer (data);
finish:
return importer;
}
static GstClapperImporterData *
_fill_importer_data (const gchar *module_path)
{
MakeCaps make_caps;
GstClapperImporterData *data;
data = g_new0 (GstClapperImporterData, 1);
data->module_path = g_strdup (module_path);
data->open_module = g_module_open (data->module_path, G_MODULE_BIND_LAZY);
if (!data->open_module)
goto fail;
if (!g_module_symbol (data->open_module, "make_caps", (gpointer *) &make_caps)
|| make_caps == NULL) {
GST_WARNING ("Make caps function missing in importer");
goto fail;
}
data->caps = make_caps (&data->rank, &data->context_types);
GST_DEBUG ("Caps reading %ssuccessful", data->caps ? "" : "un");
if (!data->caps)
goto fail;
/* Once we obtain importer data, close module afterwards */
_close_importer (data);
return data;
fail:
gst_clapper_importer_data_free (data);
return NULL;
}
static gint
_sort_importers_cb (gconstpointer a, gconstpointer b)
{
GstClapperImporterData *data_a, *data_b;
data_a = *((GstClapperImporterData **) a);
data_b = *((GstClapperImporterData **) b);
return (data_b->rank - data_a->rank);
}
static gpointer
_obtain_available_importers (G_GNUC_UNUSED gpointer data)
{
GPtrArray *importers;
GFile *dir;
GFileEnumerator *dir_enum;
GError *error = NULL;
importers = g_ptr_array_new_with_free_func (
(GDestroyNotify) gst_clapper_importer_data_free);
GST_INFO ("Checking available clapper sink importers");
dir = g_file_new_for_path (CLAPPER_SINK_IMPORTER_PATH);
if ((dir_enum = g_file_enumerate_children (dir,
G_FILE_ATTRIBUTE_STANDARD_NAME,
G_FILE_QUERY_INFO_NOFOLLOW_SYMLINKS, NULL, &error))) {
while (TRUE) {
GFileInfo *info = NULL;
GstClapperImporterData *data;
gchar *module_path;
const gchar *module_name;
if (!g_file_enumerator_iterate (dir_enum, &info,
NULL, NULL, &error) || !info)
break;
module_name = g_file_info_get_name (info);
if (!g_str_has_suffix (module_name, G_MODULE_SUFFIX))
continue;
module_path = g_module_build_path (CLAPPER_SINK_IMPORTER_PATH, module_name);
data = _fill_importer_data (module_path);
g_free (module_path);
if (!data) {
GST_WARNING ("Could not read importer data: %s", module_name);
continue;
}
GST_INFO ("Found importer: %s, caps: %" GST_PTR_FORMAT, module_name, data->caps);
g_ptr_array_add (importers, data);
}
}
g_object_unref (dir);
g_object_unref (dir_enum);
if (error) {
GST_ERROR ("Could not load importer, reason: %s",
(error->message) ? error->message : "unknown");
g_error_free (error);
}
g_ptr_array_sort (importers, (GCompareFunc) _sort_importers_cb);
return importers;
}
static const GPtrArray *
gst_clapper_importer_loader_get_available_importers (void)
{
static GOnce once = G_ONCE_INIT;
g_once (&once, _obtain_available_importers, NULL);
return (const GPtrArray *) once.retval;
}
static GstClapperImporterData *
_find_open_importer_data (const GPtrArray *importers)
{
guint i;
for (i = 0; i < importers->len; i++) {
GstClapperImporterData *data = g_ptr_array_index (importers, i);
if (data->open_module)
return data;
}
return NULL;
}
static GstClapperImporterData *
_get_importer_data_for_caps (const GPtrArray *importers, const GstCaps *caps)
{
guint i;
for (i = 0; i < importers->len; i++) {
GstClapperImporterData *data = g_ptr_array_index (importers, i);
if (!gst_caps_is_always_compatible (caps, data->caps))
continue;
return data;
}
return NULL;
}
static GstClapperImporterData *
_get_importer_data_for_context_type (const GPtrArray *importers, const gchar *context_type)
{
guint i;
for (i = 0; i < importers->len; i++) {
GstClapperImporterData *data = g_ptr_array_index (importers, i);
guint j;
if (!data->context_types)
continue;
for (j = 0; data->context_types[j]; j++) {
if (strcmp (context_type, data->context_types[j]))
continue;
return data;
}
}
return NULL;
}
void
gst_clapper_importer_loader_unload_all (void)
{
const GPtrArray *importers;
guint i;
importers = gst_clapper_importer_loader_get_available_importers ();
GST_TRACE ("Unloading all open modules");
for (i = 0; i < importers->len; i++) {
GstClapperImporterData *data = g_ptr_array_index (importers, i);
_close_importer (data);
}
}
GstPadTemplate *
gst_clapper_importer_loader_make_sink_pad_template (void)
{
const GPtrArray *importers;
GstCaps *sink_caps;
GstPadTemplate *templ;
guint i;
/* This is only called once from sink class init function */
GST_DEBUG_CATEGORY_INIT (GST_CAT_DEFAULT, "clapperimporterloader", 0,
"Clapper Importer Loader");
importers = gst_clapper_importer_loader_get_available_importers ();
sink_caps = gst_caps_new_empty ();
for (i = 0; i < importers->len; i++) {
GstClapperImporterData *data = g_ptr_array_index (importers, i);
GstCaps *copied_caps;
copied_caps = gst_caps_copy (data->caps);
gst_caps_append (sink_caps, copied_caps);
}
if (G_UNLIKELY (gst_caps_is_empty (sink_caps)))
gst_caps_append (sink_caps, gst_caps_new_any ());
templ = gst_pad_template_new ("sink", GST_PAD_SINK, GST_PAD_ALWAYS, sink_caps);
gst_caps_unref (sink_caps);
return templ;
}
static gboolean
_find_importer_internal (GstCaps *caps, GstQuery *query, GstClapperImporter **importer)
{
const GPtrArray *importers;
GstClapperImporterData *old_data = NULL, *new_data = NULL;
GstClapperImporter *found_importer = NULL;
importers = gst_clapper_importer_loader_get_available_importers ();
old_data = _find_open_importer_data (importers);
if (caps) {
GST_DEBUG ("Requested importer for caps: %" GST_PTR_FORMAT, caps);
new_data = _get_importer_data_for_caps (importers, caps);
} else if (query) {
const gchar *context_type;
gst_query_parse_context_type (query, &context_type);
GST_DEBUG ("Requested importer for context: %s", context_type);
new_data = _get_importer_data_for_context_type (importers, context_type);
/* In case missing importer for context query, leave the old one.
* We should allow some queries to go through unresponded */
if (!new_data)
new_data = old_data;
}
GST_LOG ("Old importer path: %s, new path: %s",
(old_data != NULL) ? old_data->module_path : NULL,
(new_data != NULL) ? new_data->module_path : NULL);
if (old_data == new_data) {
GST_DEBUG ("No importer change");
if (*importer && caps)
gst_clapper_importer_set_caps (*importer, caps);
return (*importer != NULL);
}
if (new_data) {
found_importer = _obtain_importer_internal (new_data);
if (*importer && found_importer)
gst_clapper_importer_share_data (*importer, found_importer);
}
gst_clear_object (importer);
_close_importer (old_data);
if (found_importer && gst_clapper_importer_prepare (found_importer)) {
if (caps)
gst_clapper_importer_set_caps (found_importer, caps);
*importer = found_importer;
return TRUE;
}
gst_clear_object (&found_importer);
_close_importer (new_data);
return FALSE;
}
gboolean
gst_clapper_importer_loader_find_importer_for_caps (GstCaps *caps, GstClapperImporter **importer)
{
return _find_importer_internal (caps, NULL, importer);
}
gboolean
gst_clapper_importer_loader_find_importer_for_context_query (GstQuery *query, GstClapperImporter **importer)
{
return _find_importer_internal (NULL, query, importer);
}