Refer-To Header [SIP Headers]

The Refer-To header provides a URI to reference. More...

Data Structures
struct	sip_refer_to_s
	Structure for Refer-To header. More...
Defines
#define	sip_refer_to(sip)
	Access a SIP Refer-To header structure sip_refer_to_t from sip_t.
#define	SIP_REFER_TO_INIT()
	Initializer for structure sip_refer_to_t.
#define	SIPTAG_REFER_TO(x)
	Tag list item for pointer to a Refer-To header structure sip_refer_to_t.
#define	SIPTAG_REFER_TO_REF(x)
	Tag list item for reference to a Refer-To header pointer.
#define	SIPTAG_REFER_TO_STR(s)
	Tag list item for string with Refer-To header value.
#define	SIPTAG_REFER_TO_STR_REF(x)
	Tag list item for reference to a Refer-To header string.
Typedefs
typedef struct sip_refer_to_s	sip_refer_to_t
	The structure sip_refer_to_t contains representation of Refer-To header.
Functions
issize_t	sip_refer_to_d (su_home_t *, msg_header_t *, char *s, isize_t slen)
	Parse a SIP Refer-To header.
issize_t	sip_refer_to_e (char b[], isize_t bsiz, msg_header_t const *h, int flags)
	Print a SIP Refer-To header.
sip_refer_to_t *	sip_refer_to_init (sip_refer_to_t x[1])
	Initialize a structure sip_refer_to_t.
int	sip_is_refer_to (sip_header_t const *header)
	Test if header object is instance of sip_refer_to_t.
sip_refer_to_t *	sip_refer_to_dup (su_home_t *home, sip_refer_to_t const *hdr))
	Duplicate a list of Refer-To header header structures sip_refer_to_t.
sip_refer_to_t *	sip_refer_to_copy (su_home_t *home, sip_refer_to_t const *hdr))
	Copy a list of Refer-To header header structures sip_refer_to_t.
sip_refer_to_t *	sip_refer_to_make (su_home_t *home, char const *s))
	Make a Refer-To header structure sip_refer_to_t.
sip_refer_to_t *	sip_refer_to_format (su_home_t *home, char const *fmt,...)))
	Make a Refer-To header from formatting result.
Variables
msg_hclass_t	sip_refer_to_class []
	Header class for Refer-To header.
tag_typedef_t	siptag_refer_to
	Tag for Refer-To header object.
tag_typedef_t	siptag_refer_to_str
	Tag for string with Refer-To header value.

---

Detailed Description

The Refer-To header provides a URI to reference.

Its syntax is defined in RFC 3515 section 2.1 as follows:

  Refer-To = ("Refer-To" / "r") HCOLON ( name-addr / addr-spec )
            *(SEMI generic-param)

The parsed Refer-To header is stored in sip_refer_to_t structure.

---

Define Documentation

#define SIP_REFER_TO_INIT

(

)

Initializer for structure sip_refer_to_t.

A static sip_refer_to_t structure for Refer-To header must be initialized with the SIP_REFER_TO_INIT() macro. For instance,

  sip_refer_to_t sip_refer_to = SIP_REFER_TO_INIT;

#define SIPTAG_REFER_TO

(

x

)

Tag list item for pointer to a Refer-To header structure sip_refer_to_t.

The SIPTAG_REFER_TO() macro is used to include a tag item with a pointer to a sip_refer_to_t structure in a tag list.

Parameters:

x

pointer to a sip_refer_to_t structure, or NULL.

The corresponding tag taking reference parameter is SIPTAG_REFER_TO_REF().

#define SIPTAG_REFER_TO_STR

(

s

)

Tag list item for string with Refer-To header value.

The SIPTAG_REFER_TO_STR() macro is used to include a tag item with a string containing value of a sip_refer_to_t header in a tag list.

Parameters:

s

pointer to a string containing Refer-To header value, or NULL.

The string in SIPTAG_REFER_TO_STR() can be converted to a sip_refer_to_t header structure by giving the string s has second argument to function sip_refer_to_make().

The corresponding tag taking reference parameter is SIPTAG_REFER_TO_STR_REF().

---

Typedef Documentation

typedef struct sip_refer_to_s sip_refer_to_t

The structure sip_refer_to_t contains representation of Refer-To header.

The sip_refer_to_t is defined as follows:

 typedef struct sip_refer_to_s
 {
   sip_common_t        r_common[1];   // Common fragment info
   sip_error_t        *r_next;  // Link to next (dummy)
   char const          r_display;     // Display name
   url_t               r_url[1];        // URI to reference
   msg_param_t const  *r_params;      // List of generic parameters
 } sip_refer_to_t;

---

Function Documentation

int sip_is_refer_to

(

sip_header_t const *

header

)

[inline]

Test if header object is instance of sip_refer_to_t.

Check if the header class is an instance of Refer-To header object and return true (nonzero), otherwise return false (zero).

Parameters:

header

pointer to the header structure to be tested

Return values:

	1	(true) if the header is an instance of header refer_to
	0	(false) otherwise

sip_refer_to_t * sip_refer_to_copy	(	su_home_t *	home,
		sip_refer_to_t const *	hdr
	)			[inline]

Copy a list of Refer-To header header structures sip_refer_to_t.

The function sip_refer_to_copy() copies a header structure hdr. If the header structure hdr contains a reference (hdr->h_next) to a list of headers, all the headers in that list are copied, too. The function uses given memory home to allocate all the memory areas used to copy the list of header structure hdr.

Parameters:

	home	memory home used to allocate new structure
	hdr	pointer to the header structure to be copied

When copying, only the header structure and parameter lists attached to it are duplicated. The new header structure retains all the references to the strings within the old hdr header, including the encoding of the old header, if present.

Example

   refer_to = sip_refer_to_copy(home, sip->sip_refer_to);

Returns:

A pointer to newly copied header structure, or NULL upon an error.

sip_refer_to_t * sip_refer_to_dup	(	su_home_t *	home,
		sip_refer_to_t const *	hdr
	)			[inline]

Duplicate a list of Refer-To header header structures sip_refer_to_t.

Duplicate a header structure hdr. If the header structure hdr contains a reference (hdr->x_next) to a list of headers, all the headers in the list are duplicated, too.

Parameters:

	home	memory home used to allocate new structure
	hdr	header structure to be duplicated

When duplicating, all parameter lists and non-constant strings attached to the header are copied, too. The function uses given memory home to allocate all the memory areas used to copy the header.

Example

   refer_to = sip_refer_to_dup(home, sip->sip_refer_to);

Returns:

A pointer to the newly duplicated sip_refer_to_t header structure, or NULL upon an error.

sip_refer_to_t * sip_refer_to_format	(	su_home_t *	home,
		char const *	fmt,
			...
	)			[inline]

Make a Refer-To header from formatting result.

Make a new sip_refer_to_t object using formatting result as its value. The function first prints the arguments according to the format fmt specified. Then it allocates a new header structure, and parses the formatting result to the structure sip_refer_to_t.

Parameters:

	home	memory home used to allocate new header structure.
	fmt	string used as a printf()-style format
	...	argument list for format

Returns:

A pointer to newly makes header structure, or NULL upon an error.

sip_refer_to_t* sip_refer_to_init

(

sip_refer_to_t

x[1]

)

[inline]

Initialize a structure sip_refer_to_t.

An sip_refer_to_t structure for Refer-To header can be initialized with the sip_refer_to_init() function/macro. For instance,

  sip_refer_to_t sip_refer_to;

  sip_refer_to_init(&sip_refer_to);

sip_refer_to_t * sip_refer_to_make	(	su_home_t *	home,
		char const *	s
	)			[inline]

Make a Refer-To header structure sip_refer_to_t.

The function sip_refer_to_make() makes a new sip_refer_to_t header structure. It allocates a new header structure, and decodes the string s as the value of the structure.

Parameters:

	home	memory home used to allocate new header structure.
	s	string to be decoded as value of the new header structure

Returns:

A pointer to newly maked sip_refer_to_t header structure, or NULL upon an error.

---

Variable Documentation

msg_hclass_t sip_refer_to_class[]

Header class for Refer-To header.

The header class sip_refer_to_class defines how a SIP Refer-To header is parsed and printed. It also contains methods used by SIP parser and other functions to manipulate the sip_refer_to_t header structure.