add media session example beginnings

Add an example media session that runs as a separate program instead
of a module

src/modules/module-audio-dsp.c

@@ -0,0 +1,214 @@
+/* PipeWire
+ * Copyright (C) 2018 Wim Taymans <wim.taymans@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.
+ */
+
+#include <string.h>
+#include <stdio.h>
+#include <errno.h>
+#include <dlfcn.h>
+
+#include "config.h"
+
+#include "pipewire/core.h"
+#include "pipewire/interfaces.h"
+#include "pipewire/log.h"
+#include "pipewire/module.h"
+
+#include "module-media-session/audio-dsp.h"
+
+static const struct spa_dict_item module_props[] = {
+	{ PW_MODULE_PROP_AUTHOR, "Wim Taymans <wim.taymans@gmail.com>" },
+	{ PW_MODULE_PROP_DESCRIPTION, "Manage audio DSP nodes" },
+	{ PW_MODULE_PROP_VERSION, PACKAGE_VERSION },
+};
+
+struct factory_data {
+	struct pw_factory *this;
+	struct pw_properties *properties;
+
+	struct pw_module *module;
+	struct spa_hook module_listener;
+};
+
+struct resource_data {
+	struct factory_data *data;
+
+	struct pw_resource *resource;
+	struct spa_hook resource_listener;
+
+	struct pw_node *dsp;
+};
+
+static void resource_destroy(void *data)
+{
+	struct resource_data *d = data;
+	if (d->dsp)
+		pw_node_destroy(d->dsp);
+}
+
+static struct pw_resource_events resource_events =
+{
+	PW_VERSION_RESOURCE_EVENTS,
+	.destroy = resource_destroy
+};
+
+static void *create_object(void *_data,
+			   struct pw_resource *resource,
+			   uint32_t type,
+			   uint32_t version,
+			   struct pw_properties *properties,
+			   uint32_t new_id)
+{
+	struct factory_data *d = _data;
+	struct resource_data *rd;
+	struct pw_resource *node_resource;
+	struct pw_client *client;
+	int channels, rate, maxbuffer;
+	const char *str;
+	enum pw_direction direction;
+
+	if (resource == NULL)
+		goto no_resource;
+
+	client = pw_resource_get_client(resource);
+
+	node_resource = pw_resource_new(client,
+					new_id, PW_PERM_RWX, type, version,
+					sizeof(struct resource_data));
+	if (node_resource == NULL)
+		goto no_mem;
+
+	rd = pw_resource_get_user_data(node_resource);
+	rd->data = d;
+	rd->resource = node_resource;
+
+	pw_resource_add_listener(node_resource, &rd->resource_listener, &resource_events, rd);
+
+	if ((str = pw_properties_get(properties, "audio-dsp.direction")) == NULL)
+		goto no_props;
+
+	direction = pw_properties_parse_int(str);
+
+	if ((str = pw_properties_get(properties, "audio-dsp.channels")) == NULL)
+		goto no_props;
+
+	channels = pw_properties_parse_int(str);
+
+	if ((str = pw_properties_get(properties, "audio-dsp.rate")) == NULL)
+		goto no_props;
+
+	rate = pw_properties_parse_int(str);
+
+	if ((str = pw_properties_get(properties, "audio-dsp.maxbuffer")) == NULL)
+		goto no_props;
+
+	maxbuffer = pw_properties_parse_int(str);
+
+	rd->dsp = pw_audio_dsp_new(pw_module_get_core(d->module),
+			properties,
+			direction,
+			channels, rate, maxbuffer, 0);
+
+	if (rd->dsp == NULL)
+		goto no_mem;
+
+	pw_node_register(rd->dsp, client, pw_module_get_global(d->module), NULL);
+	pw_node_set_active(rd->dsp, true);
+
+	return rd->dsp;
+
+      no_resource:
+	pw_log_error("audio-dsp needs a resource");
+	pw_resource_error(resource, -EINVAL, "no resource");
+	goto done;
+      no_props:
+	pw_log_error("audio-dsp needs a property");
+	pw_resource_error(resource, -EINVAL, "no property");
+	goto done;
+      no_mem:
+	pw_log_error("can't create node");
+	pw_resource_error(resource, -ENOMEM, "no memory");
+	goto done;
+      done:
+	if (properties)
+		pw_properties_free(properties);
+	return NULL;
+}
+
+static const struct pw_factory_implementation impl_factory = {
+	PW_VERSION_FACTORY_IMPLEMENTATION,
+	.create_object = create_object,
+};
+
+static void module_destroy(void *data)
+{
+	struct factory_data *d = data;
+
+	spa_hook_remove(&d->module_listener);
+
+	if (d->properties)
+		pw_properties_free(d->properties);
+
+	pw_factory_destroy(d->this);
+}
+
+static const struct pw_module_events module_events = {
+	PW_VERSION_MODULE_EVENTS,
+	.destroy = module_destroy,
+};
+
+static int module_init(struct pw_module *module, struct pw_properties *properties)
+{
+	struct pw_core *core = pw_module_get_core(module);
+	struct pw_type *t = pw_core_get_type(core);
+	struct pw_factory *factory;
+	struct factory_data *data;
+
+	factory = pw_factory_new(core,
+				 "audio-dsp",
+				 t->node,
+				 PW_VERSION_NODE,
+				 NULL,
+				 sizeof(*data));
+	if (factory == NULL)
+		return -ENOMEM;
+
+	data = pw_factory_get_user_data(factory);
+	data->this = factory;
+	data->module = module;
+	data->properties = properties;
+
+	pw_log_debug("module %p: new", module);
+
+	pw_factory_set_implementation(factory,
+				      &impl_factory,
+				      data);
+
+	pw_factory_register(factory, NULL, pw_module_get_global(module), NULL);
+
+	pw_module_add_listener(module, &data->module_listener, &module_events, data);
+
+	pw_module_update_properties(module, &SPA_DICT_INIT_ARRAY(module_props));
+
+	return 0;
+}
+
+int pipewire__module_init(struct pw_module *module, const char *args)
+{
+	return module_init(module, NULL);
+}