Properties

Properties are used to pass around arbitrary key/value pairs. More...

Files
file	properties.h
	pipewire/properties.h

Data Structures
struct	pw_properties

Macros
#define	PW_PROPERTIES_FLAG_NL   (1<<0)

Functions
struct pw_properties *	pw_properties_new (const char *key,...) 1
	Make a new properties object. More...
struct pw_properties *	pw_properties_new_dict (const struct spa_dict *dict)
	Make a new properties object from the given dictionary. More...
struct pw_properties *	pw_properties_new_string (const char *args)
	Make a new properties object from the given str. More...
struct pw_properties *	pw_properties_copy (const struct pw_properties *properties)
	Copy a properties object. More...
int	pw_properties_update_keys (struct pw_properties *props, const struct spa_dict *dict, const char *const keys[])
	Copy multiple keys from one property to another. More...
int	pw_properties_update_ignore (struct pw_properties *props, const struct spa_dict *dict, const char *const ignore[])
int	pw_properties_update (struct pw_properties *props, const struct spa_dict *dict)
	Update properties. More...
int	pw_properties_update_string (struct pw_properties *props, const char *str, size_t size)
	Update the properties from the given string, overwriting any existing keys with the new values from str. More...
int	pw_properties_add (struct pw_properties *oldprops, const struct spa_dict *dict)
	Add properties. More...
int	pw_properties_add_keys (struct pw_properties *oldprops, const struct spa_dict *dict, const char *const keys[])
	Add keys. More...
void	pw_properties_clear (struct pw_properties *properties)
	Clear a properties object. More...
void	pw_properties_free (struct pw_properties *properties)
	Free a properties object. More...
int	pw_properties_set (struct pw_properties *properties, const char *key, const char *value)
	Set a property value. More...
int	pw_properties_setf (struct pw_properties *properties, const char *key, const char *format,...) 1(3
int int	pw_properties_setva (struct pw_properties *properties, const char *key, const char *format, va_list args) 1(3
int int const char *	pw_properties_get (const struct pw_properties *properties, const char *key)
	Get a property. More...
int	pw_properties_fetch_uint32 (const struct pw_properties *properties, const char *key, uint32_t *value)
	Fetch a property as uint32_t. More...
int	pw_properties_fetch_int32 (const struct pw_properties *properties, const char *key, int32_t *value)
	Fetch a property as int32_t. More...
int	pw_properties_fetch_uint64 (const struct pw_properties *properties, const char *key, uint64_t *value)
	Fetch a property as uint64_t. More...
int	pw_properties_fetch_int64 (const struct pw_properties *properties, const char *key, int64_t *value)
	Fetch a property as int64_t. More...
int	pw_properties_fetch_bool (const struct pw_properties *properties, const char *key, bool *value)
	Fetch a property as boolean value. More...
static uint32_t	pw_properties_get_uint32 (const struct pw_properties *properties, const char *key, uint32_t deflt)
static int32_t	pw_properties_get_int32 (const struct pw_properties *properties, const char *key, int32_t deflt)
static uint64_t	pw_properties_get_uint64 (const struct pw_properties *properties, const char *key, uint64_t deflt)
static int64_t	pw_properties_get_int64 (const struct pw_properties *properties, const char *key, int64_t deflt)
static bool	pw_properties_get_bool (const struct pw_properties *properties, const char *key, bool deflt)
const char *	pw_properties_iterate (const struct pw_properties *properties, void **state)
	Iterate property values. More...
int	pw_properties_serialize_dict (FILE *f, const struct spa_dict *dict, uint32_t flags)
static bool	pw_properties_parse_bool (const char *value)
static int	pw_properties_parse_int (const char *value)
static int64_t	pw_properties_parse_int64 (const char *value)
static uint64_t	pw_properties_parse_uint64 (const char *value)
static float	pw_properties_parse_float (const char *value)
static double	pw_properties_parse_double (const char *value)

Detailed Description

Properties are used to pass around arbitrary key/value pairs.

Both keys and values are strings which keeps things simple. Encoding of arbitrary values should be done by using a string serialization such as base64 for binary blobs.

Macro Definition Documentation

PW_PROPERTIES_FLAG_NL

#define PW_PROPERTIES_FLAG_NL   (1<<0)

Function Documentation

pw_properties_new()

struct pw_properties* pw_properties_new	(	const char *	key,
			...
	)

Make a new properties object.

Parameters

key	a first key
...	value and more keys NULL terminated

Returns

a newly allocated properties object

Examples

audio-capture.c, audio-dsp-filter.c, audio-dsp-src.c, audio-src.c, export-sink.c, export-source.c, export-spa-device.c, export-spa.c, local-v4l2.c, tutorial4.c, tutorial5.c, video-dsp-play.c, video-play-fixate.c, video-play-pull.c, video-play-reneg.c, video-play.c, video-src-alloc.c, video-src-fixate.c, video-src-reneg.c, and video-src.c.

pw_properties_new_dict()

struct pw_properties* pw_properties_new_dict

(

const struct spa_dict *

dict

)

Make a new properties object from the given dictionary.

Parameters

dict	a dictionary. keys and values are copied

Returns

a new properties object

pw_properties_new_string()

struct pw_properties* pw_properties_new_string

(

const char *

object

)

Make a new properties object from the given str.

object should be a whitespace separated list of key=value strings or a json object.

Parameters

object

a property description

Returns

a new properties object

pw_properties_copy()

struct pw_properties* pw_properties_copy

(

const struct pw_properties *

properties

)

Copy a properties object.

Parameters

properties

properties to copy

Returns

a new properties object

pw_properties_update_keys()

int pw_properties_update_keys	(	struct pw_properties *	props,
		const struct spa_dict *	dict,
		const char *const	keys[]
	)

Copy multiple keys from one property to another.

Parameters

props	properties to copy to
dict	properties to copy from
keys	a NULL terminated list of keys to copy

Returns

the number of keys changed in dest

pw_properties_update_ignore()

int pw_properties_update_ignore	(	struct pw_properties *	props,
		const struct spa_dict *	dict,
		const char *const	ignore[]
	)

pw_properties_update()

int pw_properties_update	(	struct pw_properties *	props,
		const struct spa_dict *	dict
	)

Update properties.

Parameters

props	properties to update
dict	new properties

Returns

the number of changed properties

The properties in props are updated with dict. Keys in dict with NULL values are removed from props.

pw_properties_update_string()

int pw_properties_update_string	(	struct pw_properties *	props,
		const char *	str,
		size_t	size
	)

Update the properties from the given string, overwriting any existing keys with the new values from str.

str should be a whitespace separated list of key=value strings or a json object, see pw_properties_new_string().

Returns

The number of properties added or updated

pw_properties_add()

int pw_properties_add	(	struct pw_properties *	props,
		const struct spa_dict *	dict
	)

Add properties.

Parameters

props	properties to add
dict	new properties

Returns

the number of added properties

The properties from dict that are not yet in props are added.

pw_properties_add_keys()

int pw_properties_add_keys	(	struct pw_properties *	props,
		const struct spa_dict *	dict,
		const char *const	keys[]
	)

Add keys.

Parameters

props	properties to add
dict	new properties
keys	a NULL terminated list of keys to add

Returns

the number of added properties

The properties with keys from dict that are not yet in props are added.

pw_properties_clear()

void pw_properties_clear

(

struct pw_properties *

properties

)

Clear a properties object.

Parameters

properties

properties to clear

Examples

local-v4l2.c.

pw_properties_free()

void pw_properties_free

(

struct pw_properties *

properties

)

Free a properties object.

Parameters

properties

the properties to free

Examples

export-sink.c, export-source.c, export-spa.c, and local-v4l2.c.

pw_properties_set()

int pw_properties_set	(	struct pw_properties *	properties,
		const char *	key,
		const char *	value
	)

Set a property value.

Parameters

properties	the properties to change
key	a key
value	a value or NULL to remove the key

Returns

1 if the properties were changed. 0 if nothing was changed because the property already existed with the same value or because the key to remove did not exist.

Set the property in properties with key to value. Any previous value of key will be overwritten. When value is NULL, the key will be removed.

Examples

audio-capture.c, audio-src.c, export-sink.c, export-source.c, export-spa.c, tutorial5.c, video-play-fixate.c, video-play-pull.c, video-play-reneg.c, and video-play.c.

pw_properties_setf()

int pw_properties_setf	(	struct pw_properties *	properties,
		const char *	key,
		const char *	format,
			...
	)

Examples

local-v4l2.c.

pw_properties_setva()

int int pw_properties_setva	(	struct pw_properties *	properties,
		const char *	key,
		const char *	format,
		va_list	args
	)

pw_properties_get()

int int const char* pw_properties_get	(	const struct pw_properties *	properties,
		const char *	key
	)

Get a property.

Parameters

properties	a Properties
key	a key

Returns

the property for key or NULL when the key was not found

Get the property in properties with key.

pw_properties_fetch_uint32()

int pw_properties_fetch_uint32	(	const struct pw_properties *	properties,
		const char *	key,
		uint32_t *	value
	)

Fetch a property as uint32_t.

Parameters

properties	a Properties
key	a key
value	set to the value of the property on success, otherwise left unmodified

Returns

0 on success or a negative errno otherwise

Return values

-ENOENT	The property does not exist
-EINVAL	The property is not in the expected format

pw_properties_fetch_int32()

int pw_properties_fetch_int32	(	const struct pw_properties *	properties,
		const char *	key,
		int32_t *	value
	)

Fetch a property as int32_t.

Parameters

properties	a Properties
key	a key
value	set to the value of the property on success, otherwise left unmodified

Returns

0 on success or a negative errno otherwise

Return values

-ENOENT	The property does not exist
-EINVAL	The property is not in the expected format

pw_properties_fetch_uint64()

int pw_properties_fetch_uint64	(	const struct pw_properties *	properties,
		const char *	key,
		uint64_t *	value
	)

Fetch a property as uint64_t.

Parameters

properties	a Properties
key	a key
value	set to the value of the property on success, otherwise left unmodified

Returns

0 on success or a negative errno otherwise

Return values

-ENOENT	The property does not exist
-EINVAL	The property is not in the expected format

pw_properties_fetch_int64()

int pw_properties_fetch_int64	(	const struct pw_properties *	properties,
		const char *	key,
		int64_t *	value
	)

Fetch a property as int64_t.

Parameters

properties	a Properties
key	a key
value	set to the value of the property on success, otherwise left unmodified

Returns

0 on success or a negative errno otherwise

Return values

-ENOENT	The property does not exist
-EINVAL	The property is not in the expected format

pw_properties_fetch_bool()

int pw_properties_fetch_bool	(	const struct pw_properties *	properties,
		const char *	key,
		bool *	value
	)

Fetch a property as boolean value.

Parameters

properties	a Properties
key	a key
value	set to the value of the property on success, otherwise left unmodified

Returns

0 on success or a negative errno otherwise

Return values

-ENOENT	The property does not exist
-EINVAL	The property is not in the expected format

pw_properties_get_uint32()

static uint32_t pw_properties_get_uint32 ( const struct pw_properties *  properties, const char *  key, uint32_t  deflt  )

inlinestatic

pw_properties_get_int32()

static int32_t pw_properties_get_int32 ( const struct pw_properties *  properties, const char *  key, int32_t  deflt  )

inlinestatic

pw_properties_get_uint64()

static uint64_t pw_properties_get_uint64 ( const struct pw_properties *  properties, const char *  key, uint64_t  deflt  )

inlinestatic

pw_properties_get_int64()

static int64_t pw_properties_get_int64 ( const struct pw_properties *  properties, const char *  key, int64_t  deflt  )

inlinestatic

pw_properties_get_bool()

static bool pw_properties_get_bool ( const struct pw_properties *  properties, const char *  key, bool  deflt  )

inlinestatic

pw_properties_iterate()

const char* pw_properties_iterate	(	const struct pw_properties *	properties,
		void **	state
	)

Iterate property values.

Parameters

properties	a Properties
state	state

Returns

The next key or NULL when there are no more keys to iterate.

Iterate over properties, returning each key in turn. state should point to a pointer holding NULL to get the first element and will be updated after each iteration. When NULL is returned, all elements have been iterated.

pw_properties_serialize_dict()

int pw_properties_serialize_dict	(	FILE *	f,
		const struct spa_dict *	dict,
		uint32_t	flags
	)

pw_properties_parse_bool()

static bool pw_properties_parse_bool ( const char *  value )

inlinestatic

pw_properties_parse_int()

static int pw_properties_parse_int ( const char *  value )

inlinestatic

pw_properties_parse_int64()

static int64_t pw_properties_parse_int64 ( const char *  value )

inlinestatic

pw_properties_parse_uint64()

static uint64_t pw_properties_parse_uint64 ( const char *  value )

inlinestatic

pw_properties_parse_float()

static float pw_properties_parse_float ( const char *  value )

inlinestatic

pw_properties_parse_double()

static double pw_properties_parse_double ( const char *  value )

inlinestatic