Node

Node interface More...

Files
file	node.h
	pipewire/node.h

Data Structures
struct	pw_node_info
	The node information. More...
struct	pw_node_events
	Node events. More...
struct	pw_node_methods
	Node methods. More...
struct	pw_node

Enumerations
enum	pw_node_state {   PW_NODE_STATE_ERROR = -1 , PW_NODE_STATE_CREATING = 0 , PW_NODE_STATE_SUSPENDED = 1 , PW_NODE_STATE_IDLE = 2 ,   PW_NODE_STATE_RUNNING = 3 }
	The different node states. More...

Macros
#define	PW_TYPE_INTERFACE_Node   PW_TYPE_INFO_INTERFACE_BASE "Node"
#define	PW_NODE_PERM_MASK   PW_PERM_RWXML
#define	PW_VERSION_NODE   3
#define	PW_API_NODE_IMPL   static inline
#define	PW_NODE_CHANGE_MASK_INPUT_PORTS   (1 << 0)
#define	PW_NODE_CHANGE_MASK_OUTPUT_PORTS   (1 << 1)
#define	PW_NODE_CHANGE_MASK_STATE   (1 << 2)
#define	PW_NODE_CHANGE_MASK_PROPS   (1 << 3)
#define	PW_NODE_CHANGE_MASK_PARAMS   (1 << 4)
#define	PW_NODE_CHANGE_MASK_ALL   ((1 << 5)-1)
#define	PW_NODE_EVENT_INFO   0
#define	PW_NODE_EVENT_PARAM   1
#define	PW_NODE_EVENT_NUM   2
#define	PW_VERSION_NODE_EVENTS   0
#define	PW_NODE_METHOD_ADD_LISTENER   0
#define	PW_NODE_METHOD_SUBSCRIBE_PARAMS   1
#define	PW_NODE_METHOD_ENUM_PARAMS   2
#define	PW_NODE_METHOD_SET_PARAM   3
#define	PW_NODE_METHOD_SEND_COMMAND   4
#define	PW_NODE_METHOD_NUM   5
#define	PW_VERSION_NODE_METHODS   0

Functions
const char *	pw_node_state_as_string (enum pw_node_state state)
	Convert a pw_node_state to a readable string.
struct pw_node_info *	pw_node_info_update (struct pw_node_info *info, const struct pw_node_info *update)
struct pw_node_info *	pw_node_info_merge (struct pw_node_info *info, const struct pw_node_info *update, bool reset)
void	pw_node_info_free (struct pw_node_info *info)
PW_API_NODE_IMPL int	pw_node_add_listener (struct pw_node *object, struct spa_hook *listener, const struct pw_node_events *events, void *data)
PW_API_NODE_IMPL int	pw_node_subscribe_params (struct pw_node *object, uint32_t *ids, uint32_t n_ids)
	Subscribe to parameter changes.
PW_API_NODE_IMPL int	pw_node_enum_params (struct pw_node *object, int seq, uint32_t id, uint32_t start, uint32_t num, const struct spa_pod *filter)
	Enumerate node parameters.
PW_API_NODE_IMPL int	pw_node_set_param (struct pw_node *object, uint32_t id, uint32_t flags, const struct spa_pod *param)
	Set a parameter on the node.
PW_API_NODE_IMPL int	pw_node_send_command (struct pw_node *object, const struct spa_command *command)
	Send a command to the node.

Detailed Description

Node interface

Enumeration Type Documentation

pw_node_state

enum pw_node_state

The different node states.

Enumerator
PW_NODE_STATE_ERROR	error state
PW_NODE_STATE_CREATING	the node is being created
PW_NODE_STATE_SUSPENDED	the node is suspended, the device might be closed
PW_NODE_STATE_IDLE	the node is running but there is no active port
PW_NODE_STATE_RUNNING	the node is running

Macro Definition Documentation

PW_TYPE_INTERFACE_Node

#define PW_TYPE_INTERFACE_Node   PW_TYPE_INFO_INTERFACE_BASE "Node"

Examples

internal.c.

PW_NODE_PERM_MASK

#define PW_NODE_PERM_MASK   PW_PERM_RWXML

PW_VERSION_NODE

#define PW_VERSION_NODE   3

Examples

internal.c.

PW_API_NODE_IMPL

#define PW_API_NODE_IMPL   static inline

PW_NODE_CHANGE_MASK_INPUT_PORTS

#define PW_NODE_CHANGE_MASK_INPUT_PORTS   (1 << 0)

PW_NODE_CHANGE_MASK_OUTPUT_PORTS

#define PW_NODE_CHANGE_MASK_OUTPUT_PORTS   (1 << 1)

PW_NODE_CHANGE_MASK_STATE

#define PW_NODE_CHANGE_MASK_STATE   (1 << 2)

PW_NODE_CHANGE_MASK_PROPS

#define PW_NODE_CHANGE_MASK_PROPS   (1 << 3)

PW_NODE_CHANGE_MASK_PARAMS

#define PW_NODE_CHANGE_MASK_PARAMS   (1 << 4)

PW_NODE_CHANGE_MASK_ALL

#define PW_NODE_CHANGE_MASK_ALL   ((1 << 5)-1)

PW_NODE_EVENT_INFO

#define PW_NODE_EVENT_INFO   0

PW_NODE_EVENT_PARAM

#define PW_NODE_EVENT_PARAM   1

PW_NODE_EVENT_NUM

#define PW_NODE_EVENT_NUM   2

PW_VERSION_NODE_EVENTS

#define PW_VERSION_NODE_EVENTS   0

PW_NODE_METHOD_ADD_LISTENER

#define PW_NODE_METHOD_ADD_LISTENER   0

PW_NODE_METHOD_SUBSCRIBE_PARAMS

#define PW_NODE_METHOD_SUBSCRIBE_PARAMS   1

PW_NODE_METHOD_ENUM_PARAMS

#define PW_NODE_METHOD_ENUM_PARAMS   2

PW_NODE_METHOD_SET_PARAM

#define PW_NODE_METHOD_SET_PARAM   3

PW_NODE_METHOD_SEND_COMMAND

#define PW_NODE_METHOD_SEND_COMMAND   4

PW_NODE_METHOD_NUM

#define PW_NODE_METHOD_NUM   5

PW_VERSION_NODE_METHODS

#define PW_VERSION_NODE_METHODS   0

Function Documentation

pw_node_state_as_string()

const char * pw_node_state_as_string

(

enum pw_node_state

state

)

Convert a pw_node_state to a readable string.

pw_node_info_update()

struct pw_node_info * pw_node_info_update	(	struct pw_node_info *	info,
		const struct pw_node_info *	update )

pw_node_info_merge()

struct pw_node_info * pw_node_info_merge	(	struct pw_node_info *	info,
		const struct pw_node_info *	update,
		bool	reset )

pw_node_info_free()

void pw_node_info_free

(

struct pw_node_info *

info

)

pw_node_add_listener()

PW_API_NODE_IMPL int pw_node_add_listener	(	struct pw_node *	object,
		struct spa_hook *	listener,
		const struct pw_node_events *	events,
		void *	data )

See also

pw_node_methods.add_listener

pw_node_subscribe_params()

PW_API_NODE_IMPL int pw_node_subscribe_params	(	struct pw_node *	object,
		uint32_t *	ids,
		uint32_t	n_ids )

Subscribe to parameter changes.

Automatically emit param events for the given ids when they are changed.

Parameters

ids	an array of param ids
n_ids	the number of ids in ids

This requires X permissions on the node.

See also

pw_node_methods.subscribe_params

pw_node_enum_params()

PW_API_NODE_IMPL int pw_node_enum_params	(	struct pw_node *	object,
		int	seq,
		uint32_t	id,
		uint32_t	start,
		uint32_t	num,
		const struct spa_pod *	filter )

Enumerate node parameters.

Start enumeration of node parameters. For each param, a param event will be emitted.

Parameters

seq	a sequence number to place in the reply
id	the parameter id to enum or PW_ID_ANY for all
start	the start index or 0 for the first param
num	the maximum number of params to retrieve
filter	a param filter or NULL

This requires X permissions on the node.

See also

pw_node_methods.enum_params

pw_node_set_param()

PW_API_NODE_IMPL int pw_node_set_param	(	struct pw_node *	object,
		uint32_t	id,
		uint32_t	flags,
		const struct spa_pod *	param )

Set a parameter on the node.

Parameters

id	the parameter id to set
flags	extra parameter flags
param	the parameter to set

This requires X and W permissions on the node.

See also

pw_node_methods.set_param

pw_node_send_command()

PW_API_NODE_IMPL int pw_node_send_command	(	struct pw_node *	object,
		const struct spa_command *	command )

Send a command to the node.

Parameters

command

the command to send

This requires X and W permissions on the node.

See also

pw_node_methods.send_command