Reason Header [SIP Headers]

The Reason header is used to indicate why a SIP request was issued or why a provisional response was sent. More...

Data Structures
struct	sip_reason_s
	Structure for Reason header field. More...
Defines
#define	sip_reason(sip)
	Access a SIP Reason header structure sip_reason_t from sip_t.
#define	SIP_REASON_INIT()
	Initializer for structure sip_reason_t.
#define	SIPTAG_REASON(x)
	Tag list item for pointer to a Reason header structure sip_reason_t.
#define	SIPTAG_REASON_REF(x)
	Tag list item for reference to a Reason header pointer.
#define	SIPTAG_REASON_STR(s)
	Tag list item for string with Reason header value.
#define	SIPTAG_REASON_STR_REF(x)
	Tag list item for reference to a Reason header string.
Typedefs
typedef struct sip_reason_s	sip_reason_t
	The structure sip_reason_t contains representation of SIP Reason header.
Functions
issize_t	sip_reason_d (su_home_t *, msg_header_t *, char *s, isize_t slen)
	Parse a SIP Reason header.
issize_t	sip_reason_e (char b[], isize_t bsiz, msg_header_t const *h, int flags)
	Print a SIP Reason header.
sip_reason_t *	sip_reason_init (sip_reason_t x[1])
	Initialize a structure sip_reason_t.
int	sip_is_reason (sip_header_t const *header)
	Test if header object is instance of sip_reason_t.
sip_reason_t *	sip_reason_dup (su_home_t *home, sip_reason_t const *hdr))
	Duplicate a list of Reason header header structures sip_reason_t.
sip_reason_t *	sip_reason_copy (su_home_t *home, sip_reason_t const *hdr))
	Copy a list of Reason header header structures sip_reason_t.
sip_reason_t *	sip_reason_make (su_home_t *home, char const *s))
	Make a Reason header structure sip_reason_t.
sip_reason_t *	sip_reason_format (su_home_t *home, char const *fmt,...)))
	Make a Reason header from formatting result.
Variables
msg_hclass_t	sip_reason_class []
	Header class for Reason header.
tag_typedef_t	siptag_reason
	Tag for Reason header object.
tag_typedef_t	siptag_reason_str
	Tag for string with Reason header value.

---

Detailed Description

The Reason header is used to indicate why a SIP request was issued or why a provisional response was sent.

It can be used with HRPF scenarios. It is defined in RFC 3326 as follows:

   Reason            =  "Reason" HCOLON reason-value *(COMMA reason-value)
   reason-value      =  protocol *(SEMI reason-params)
   protocol          =  "SIP" / "Q.850" / token
   reason-params     =  protocol-cause / reason-text
                        / reason-extension
   protocol-cause    =  "cause" EQUAL cause
   cause             =  1*DIGIT
   reason-text       =  "text" EQUAL quoted-string
   reason-extension  =  generic-param

The parsed Reason header is stored in sip_reason_t structure.

---

Define Documentation

#define SIP_REASON_INIT

(

)

Initializer for structure sip_reason_t.

A static sip_reason_t structure for Reason header must be initialized with the SIP_REASON_INIT() macro. For instance,

  sip_reason_t sip_reason = SIP_REASON_INIT;

#define SIPTAG_REASON

(

x

)

Tag list item for pointer to a Reason header structure sip_reason_t.

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

Parameters:

x

pointer to a sip_reason_t structure, or NULL.

The corresponding tag taking reference parameter is SIPTAG_REASON_REF().

#define SIPTAG_REASON_STR

(

s

)

Tag list item for string with Reason header value.

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

Parameters:

s

pointer to a string containing Reason header value, or NULL.

The string in SIPTAG_REASON_STR() can be converted to a sip_reason_t header structure by giving the string s has second argument to function sip_reason_make().

The corresponding tag taking reference parameter is SIPTAG_REASON_STR_REF().

---

Typedef Documentation

typedef struct sip_reason_s sip_reason_t

The structure sip_reason_t contains representation of SIP Reason header.

The sip_reason_t is defined as follows:

 typedef struct sip_reason_s
 {
   sip_common_t        re_common[1]; // Common fragment info
   sip_reason_t       *re_next;      // Link to next <reason-value>
   char const         *re_protocol;  // Protocol
   msg_param_t const  *re_params;    // List of reason parameters
   char const         *re_cause;     // Value of cause parameter
   char const         *re_text;      // Value of text parameter
 } sip_reason_t;

---

Function Documentation

int sip_is_reason

(

sip_header_t const *

header

)

[inline]

Test if header object is instance of sip_reason_t.

Check if the header class is an instance of Reason 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 reason
	0	(false) otherwise

sip_reason_t * sip_reason_copy	(	su_home_t *	home,
		sip_reason_t const *	hdr
	)			[inline]

Copy a list of Reason header header structures sip_reason_t.

The function sip_reason_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

   reason = sip_reason_copy(home, sip->sip_reason);

Returns:

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

sip_reason_t * sip_reason_dup	(	su_home_t *	home,
		sip_reason_t const *	hdr
	)			[inline]

Duplicate a list of Reason header header structures sip_reason_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

   reason = sip_reason_dup(home, sip->sip_reason);

Returns:

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

sip_reason_t * sip_reason_format	(	su_home_t *	home,
		char const *	fmt,
			...
	)			[inline]

Make a Reason header from formatting result.

Make a new sip_reason_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_reason_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_reason_t* sip_reason_init

(

sip_reason_t

x[1]

)

[inline]

Initialize a structure sip_reason_t.

An sip_reason_t structure for Reason header can be initialized with the sip_reason_init() function/macro. For instance,

  sip_reason_t sip_reason;

  sip_reason_init(&sip_reason);

sip_reason_t * sip_reason_make	(	su_home_t *	home,
		char const *	s
	)			[inline]

Make a Reason header structure sip_reason_t.

The function sip_reason_make() makes a new sip_reason_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_reason_t header structure, or NULL upon an error.

---

Variable Documentation

msg_hclass_t sip_reason_class[]

Header class for Reason header.

The header class sip_reason_class defines how a SIP Reason header is parsed and printed. It also contains methods used by SIP parser and other functions to manipulate the sip_reason_t header structure.