support: add dummy driver

Add a dummy driver node with high priority. All nodes not linked
to a device node will be linked to this when they require a driver.

spa/include/spa/utils/names.h

@@ -37,6 +37,7 @@ extern "C" {
 									  *  interface */
 #define SPA_NAME_SUPPORT_SYSTEM		"support.system"		/**< A System interface */
 
+#define SPA_NAME_SUPPORT_NODE_DRIVER	"support.node.driver"		/**< A dummy driver node */
 
 /* control mixer */
 #define SPA_NAME_CONTROL_MIXER		"control.mixer"			/**< mixes control streams */

spa/plugins/support/meson.build

@@ -1,6 +1,7 @@
 spa_support_sources = ['cpu.c',
 		       'logger.c',
 		       'loop.c',
+		       'node-driver.c',
 		       'plugin.c',
 		       'system.c']
 

spa/plugins/support/node-driver.c

@@ -0,0 +1,393 @@
+/* Spa
+ *
+ * Copyright © 2020 Wim Taymans
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ */
+
+#include <errno.h>
+#include <stddef.h>
+#include <unistd.h>
+#include <string.h>
+#include <stdio.h>
+
+#include <spa/support/plugin.h>
+#include <spa/support/log.h>
+#include <spa/support/loop.h>
+#include <spa/utils/names.h>
+#include <spa/node/node.h>
+#include <spa/node/keys.h>
+#include <spa/node/io.h>
+#include <spa/node/utils.h>
+#include <spa/param/param.h>
+
+#define NAME "driver"
+
+#define DEFAULT_FREEWHEEL	false
+
+struct props {
+	bool freewheel;
+};
+
+struct impl {
+	struct spa_handle handle;
+	struct spa_node node;
+
+	struct props props;
+
+	struct spa_log *log;
+	struct spa_loop *data_loop;
+	struct spa_system *data_system;
+
+	uint64_t info_all;
+	struct spa_node_info info;
+	struct spa_param_info params[1];
+
+	struct spa_hook_list hooks;
+	struct spa_callbacks callbacks;
+
+	struct spa_io_position *position;
+	struct spa_io_clock *clock;
+
+	struct spa_source timer_source;
+	struct itimerspec timerspec;
+
+	bool started;
+	uint64_t next_time;
+};
+
+static void reset_props(struct props *props)
+{
+	props->freewheel = DEFAULT_FREEWHEEL;
+}
+
+static int impl_node_set_io(void *object, uint32_t id, void *data, size_t size)
+{
+	struct impl *this = object;
+
+	spa_return_val_if_fail(this != NULL, -EINVAL);
+
+	switch (id) {
+	case SPA_IO_Clock:
+		if (size > 0 && size < sizeof(struct spa_io_clock))
+			return -EINVAL;
+		this->clock = data;
+		break;
+	case SPA_IO_Position:
+		if (size > 0 && size < sizeof(struct spa_io_position))
+			return -EINVAL;
+		this->position = data;
+		break;
+	default:
+		return -ENOENT;
+	}
+	return 0;
+}
+
+static void set_timer(struct impl *this, uint64_t next_time)
+{
+	this->timerspec.it_value.tv_sec = next_time / SPA_NSEC_PER_SEC;
+	this->timerspec.it_value.tv_nsec = next_time % SPA_NSEC_PER_SEC;
+	spa_system_timerfd_settime(this->data_system,
+			this->timer_source.fd, SPA_FD_TIMER_ABSTIME, &this->timerspec, NULL);
+}
+
+static void on_timeout(struct spa_source *source)
+{
+	struct impl *this = source->data;
+	uint64_t expirations, nsec, duration = 10;
+	uint32_t rate;
+
+	spa_log_trace(this->log, "timeout");
+
+	if (spa_system_timerfd_read(this->data_system,
+				this->timer_source.fd, &expirations) < 0)
+		perror("read timerfd");
+
+	nsec = this->next_time;
+
+	if (SPA_LIKELY(this->position)) {
+		duration = this->position->clock.duration;
+		rate = this->position->clock.rate.denom;
+	} else {
+		duration = 1024;
+		rate = 48000;
+	}
+
+	this->next_time = nsec + duration * SPA_NSEC_PER_SEC / rate;
+
+	if (SPA_LIKELY(this->clock)) {
+		this->clock->nsec = nsec;
+		this->clock->position += duration;
+		this->clock->duration = duration;
+		this->clock->delay = 0;
+		this->clock->rate_diff = 1.0;
+		this->clock->next_nsec = this->next_time;
+	}
+
+	spa_node_call_ready(&this->callbacks,
+			SPA_STATUS_HAVE_DATA | SPA_STATUS_NEED_DATA);
+
+	set_timer(this, this->next_time);
+}
+
+static int impl_node_send_command(void *object, const struct spa_command *command)
+{
+	struct impl *this = object;
+
+	spa_return_val_if_fail(this != NULL, -EINVAL);
+	spa_return_val_if_fail(command != NULL, -EINVAL);
+
+
+	switch (SPA_NODE_COMMAND_ID(command)) {
+	case SPA_NODE_COMMAND_Start:
+	{
+		struct timespec now;
+
+		if (this->started)
+			return 0;
+
+		clock_gettime(CLOCK_MONOTONIC, &now);
+		this->next_time = SPA_TIMESPEC_TO_NSEC(&now);
+		this->started = true;
+		set_timer(this, this->next_time);
+		break;
+	}
+	case SPA_NODE_COMMAND_Suspend:
+	case SPA_NODE_COMMAND_Pause:
+		if (!this->started)
+			return 0;
+		this->started = false;
+		set_timer(this, 0);
+		break;
+	default:
+		return -ENOTSUP;
+	}
+	return 0;
+}
+
+static const struct spa_dict_item node_info_items[] = {
+	{ SPA_KEY_NODE_DRIVER, "true" },
+};
+
+static void emit_node_info(struct impl *this, bool full)
+{
+	if (full)
+		this->info.change_mask = this->info_all;
+	if (this->info.change_mask) {
+		this->info.props = &SPA_DICT_INIT_ARRAY(node_info_items);
+		spa_node_emit_info(&this->hooks, &this->info);
+		this->info.change_mask = 0;
+	}
+}
+
+static int impl_node_add_listener(void *object,
+		struct spa_hook *listener,
+		const struct spa_node_events *events,
+		void *data)
+{
+	struct impl *this = object;
+	struct spa_hook_list save;
+
+	spa_return_val_if_fail(this != NULL, -EINVAL);
+
+	spa_hook_list_isolate(&this->hooks, &save, listener, events, data);
+
+	emit_node_info(this, true);
+
+	spa_hook_list_join(&this->hooks, &save);
+
+	return 0;
+}
+
+static int
+impl_node_set_callbacks(void *object,
+			const struct spa_node_callbacks *callbacks,
+			void *data)
+{
+	struct impl *this = object;
+
+	spa_return_val_if_fail(this != NULL, -EINVAL);
+
+	this->callbacks = SPA_CALLBACKS_INIT(callbacks, data);
+
+	return 0;
+}
+
+static int impl_node_process(void *object)
+{
+	struct impl *this = object;
+	struct timespec now;
+
+	spa_return_val_if_fail(this != NULL, -EINVAL);
+	spa_log_trace(this->log, "process %d", this->props.freewheel);
+
+	if (this->props.freewheel) {
+		clock_gettime(CLOCK_MONOTONIC, &now);
+		this->next_time = SPA_TIMESPEC_TO_NSEC(&now);
+		set_timer(this, this->next_time);
+	}
+	return SPA_STATUS_OK;
+}
+
+static const struct spa_node_methods impl_node = {
+	SPA_VERSION_NODE_METHODS,
+	.add_listener = impl_node_add_listener,
+	.set_callbacks = impl_node_set_callbacks,
+	.set_io = impl_node_set_io,
+	.send_command = impl_node_send_command,
+	.process = impl_node_process,
+};
+
+static int impl_get_interface(struct spa_handle *handle, const char *type, void **interface)
+{
+	struct impl *this;
+
+	spa_return_val_if_fail(handle != NULL, -EINVAL);
+	spa_return_val_if_fail(interface != NULL, -EINVAL);
+
+	this = (struct impl *) handle;
+
+	if (strcmp(type, SPA_TYPE_INTERFACE_Node) == 0)
+		*interface = &this->node;
+	else
+		return -ENOENT;
+
+	return 0;
+}
+
+static int impl_clear(struct spa_handle *handle)
+{
+	struct impl *this;
+
+	spa_return_val_if_fail(handle != NULL, -EINVAL);
+
+	this = (struct impl *) handle;
+
+	spa_loop_remove_source(this->data_loop, &this->timer_source);
+	spa_system_close(this->data_system, this->timer_source.fd);
+
+	return 0;
+}
+
+static size_t
+impl_get_size(const struct spa_handle_factory *factory,
+	      const struct spa_dict *params)
+{
+	return sizeof(struct impl);
+}
+
+static int
+impl_init(const struct spa_handle_factory *factory,
+	  struct spa_handle *handle,
+	  const struct spa_dict *info,
+	  const struct spa_support *support,
+	  uint32_t n_support)
+{
+	struct impl *this;
+
+	spa_return_val_if_fail(factory != NULL, -EINVAL);
+	spa_return_val_if_fail(handle != NULL, -EINVAL);
+
+	handle->get_interface = impl_get_interface;
+	handle->clear = impl_clear;
+
+	this = (struct impl *) handle;
+
+	this->log = spa_support_find(support, n_support, SPA_TYPE_INTERFACE_Log);
+	this->data_loop = spa_support_find(support, n_support, SPA_TYPE_INTERFACE_DataLoop);
+	this->data_system = spa_support_find(support, n_support, SPA_TYPE_INTERFACE_DataSystem);
+
+	if (this->data_loop == NULL) {
+		spa_log_error(this->log, "a data_loop is needed");
+		return -EINVAL;
+	}
+	if (this->data_system == NULL) {
+		spa_log_error(this->log, "a data_system is needed");
+		return -EINVAL;
+	}
+
+	spa_hook_list_init(&this->hooks);
+
+	this->node.iface = SPA_INTERFACE_INIT(
+			SPA_TYPE_INTERFACE_Node,
+			SPA_VERSION_NODE,
+			&impl_node, this);
+
+	this->info_all = SPA_NODE_CHANGE_MASK_FLAGS |
+			SPA_NODE_CHANGE_MASK_PROPS |
+			SPA_NODE_CHANGE_MASK_PARAMS;
+	this->info = SPA_NODE_INFO_INIT();
+	this->info.max_input_ports = 0;
+	this->info.max_output_ports = 0;
+	this->info.flags = SPA_NODE_FLAG_RT;
+	this->params[0] = SPA_PARAM_INFO(SPA_PARAM_Props, SPA_PARAM_INFO_READWRITE);
+	this->info.params = this->params;
+	this->info.n_params = 1;
+
+	this->timer_source.func = on_timeout;
+	this->timer_source.data = this;
+	this->timer_source.fd = spa_system_timerfd_create(this->data_system, CLOCK_MONOTONIC, SPA_FD_CLOEXEC);
+	this->timer_source.mask = SPA_IO_IN;
+	this->timer_source.rmask = 0;
+	this->timerspec.it_value.tv_sec = 0;
+	this->timerspec.it_value.tv_nsec = 0;
+	this->timerspec.it_interval.tv_sec = 0;
+	this->timerspec.it_interval.tv_nsec = 0;
+
+	reset_props(&this->props);
+
+	spa_loop_add_source(this->data_loop, &this->timer_source);
+
+	return 0;
+}
+
+static const struct spa_interface_info impl_interfaces[] = {
+	{SPA_TYPE_INTERFACE_Node,},
+};
+
+static int
+impl_enum_interface_info(const struct spa_handle_factory *factory,
+			 const struct spa_interface_info **info,
+			 uint32_t *index)
+{
+	spa_return_val_if_fail(factory != NULL, -EINVAL);
+	spa_return_val_if_fail(info != NULL, -EINVAL);
+	spa_return_val_if_fail(index != NULL, -EINVAL);
+
+	switch (*index) {
+	case 0:
+		*info = &impl_interfaces[*index];
+		break;
+	default:
+		return 0;
+	}
+	(*index)++;
+	return 1;
+}
+
+const struct spa_handle_factory spa_support_node_driver_factory = {
+	SPA_VERSION_HANDLE_FACTORY,
+	SPA_NAME_SUPPORT_NODE_DRIVER,
+	NULL,
+	impl_get_size,
+	impl_init,
+	impl_enum_interface_info,
+};

spa/plugins/support/plugin.c

@@ -31,6 +31,7 @@ extern const struct spa_handle_factory spa_support_logger_factory;
 extern const struct spa_handle_factory spa_support_system_factory;
 extern const struct spa_handle_factory spa_support_cpu_factory;
 extern const struct spa_handle_factory spa_support_loop_factory;
+extern const struct spa_handle_factory spa_support_node_driver_factory;
 
 SPA_EXPORT
 int spa_handle_factory_enum(const struct spa_handle_factory **factory, uint32_t *index)
@@ -51,6 +52,9 @@ int spa_handle_factory_enum(const struct spa_handle_factory **factory, uint32_t
 	case 3:
 		*factory = &spa_support_loop_factory;
 		break;
+	case 4:
+		*factory = &spa_support_node_driver_factory;
+		break;
 	default:
 		return 0;
 	}

src/daemon/pipewire.conf.in

@@ -31,6 +31,7 @@ add-spa-lib api.v4l2.* v4l2/libspa-v4l2
 add-spa-lib api.bluez5.* bluez5/libspa-bluez5
 add-spa-lib api.vulkan.* vulkan/libspa-vulkan
 add-spa-lib api.jack.* jack/libspa-jack
+add-spa-lib support.* support/libspa-support
 #add-spa-lib videotestsrc videotestsrc/libspa-videotestsrc
 #add-spa-lib audiotestsrc audiotestsrc/libspa-audiotestsrc
 
@@ -63,6 +64,7 @@ load-module libpipewire-module-session-manager
 #create-object spa-device-factory factory.name=api.alsa.seq.bridge node.name=Internal-MIDI-Bridge
 #create-object adapter factory.name=audiotestsrc node.name=my-test
 #create-object spa-node-factory factory.name=api.vulkan.compute.source node.name=my-compute-source
+create-object spa-node-factory factory.name=support.node.driver node.name=Dummy priority.master=8000
 
 ## exec <program-name>
 #