Referer header.

The Referer header is used to redirect the recipient to a referer other than the Request-URI for completion of the request or identification of a new resource. More...

Defines
#define	HTTP_REFERER_INIT()
	Initializer for structure http_referer_t.
#define	HTTPTAG_REFERER(x)
	Tag list item for pointer to a Referer header object.
#define	HTTPTAG_REFERER_STR(s)
	Tag list item for string with Referer header value.
Typedefs
typedef struct http_location_s	http_referer_t
	The structure http_referer_t contains representation of Referer header.
Enumerations
enum	{ http_referer_hash }
Functions
http_referer_t *	http_referer_init (http_referer_t x[1])
	Initialize a structure http_referer_t.
int	http_is_referer (http_header_t const *header)
	Test if header object is instance of http_referer_t.
http_referer_t *	http_referer_dup (su_home_t *home, http_referer_t const *hdr))
	Duplicate (deep copy) http_referer_t.
http_referer_t *	http_referer_copy (su_home_t *home, http_referer_t const *hdr))
	Copy a http_referer_t header structure.
http_referer_t *	http_referer_make (su_home_t *home, char const *s))
	Make a header structure http_referer_t.
http_referer_t *	http_referer_format (su_home_t *home, char const *fmt,...)))
	Make a Referer header from formatting result.
Variables
msg_hclass_t	http_referer_class []
	Header class for HTTP Referer header.
msg_parse_f	http_referer_d
	Decode (parse) a Referer header.
msg_print_f	http_referer_e
	Encode (print) a Referer header.

---

Detailed Description

The Referer header is used to redirect the recipient to a referer other than the Request-URI for completion of the request or identification of a new resource.

Its syntax is defined in RFC 2616 section 14.30 as follows:

    Referer       = "Referer" ":" absoluteURI

---

Define Documentation

#define HTTP_REFERER_INIT

(

)

Initializer for structure http_referer_t.

A static http_referer_t structure must be initialized with the HTTP_REFERER_INIT() macro. For instance,

  http_referer_t http_referer = HTTP_REFERER_INIT;

#define HTTPTAG_REFERER

(

x

)

Tag list item for pointer to a Referer header object.

The HTTPTAG_REFERER() macro is used to include a tag item with a pointer to a http_referer_t object in a tag list.

Parameters:

x

pointer to a http_referer_t header structure, or NULL.

#define HTTPTAG_REFERER_STR

(

s

)

Tag list item for string with Referer header value.

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

Parameters:

s

pointer to a string containing http_referer_t value, or NULL.

The HTTPTAG_REFERER_STR string can be converted to a http_referer_t header structure by giving the string s has second argument to function http_referer_make().

---

Typedef Documentation

typedef struct http_referer_s http_referer_t

The structure http_referer_t contains representation of Referer header.

The http_referer_t is defined as follows:

 typedef struct http_referer_s
 {
   msg_common_t         loc_common[1];
   msg_error_t         *loc_next;
   url_t                loc_url[1];
 } http_referer_t;

---

Enumeration Type Documentation

anonymous enum

Enumerator:

http_referer_hash

Hash of Referer header.

---

Function Documentation

int http_is_referer

(

http_header_t const *

header

)

[inline]

Test if header object is instance of http_referer_t.

The function http_is_referer() returns true (nonzero) if the header class is an instance of Referer header object and false (zero) otherwise.

Parameters:

header

pointer to the header structure to be tested

Returns:

The function http_is_xreferer() returns true (nonzero) if the header object is an instance of header referer and false (zero) otherwise.

http_referer_t * http_referer_copy	(	su_home_t *	home,
		http_referer_t const *	hdr
	)			[inline]

Copy a http_referer_t header structure.

The function http_referer_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 header structure hdr.

Parameters:

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

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 header, including the encoding of the old header, if present.

Example

   referer = http_referer_copy(home, http->http_referer);

Returns:

The function http_referer_copy() returns a pointer to newly copied header structure, or NULL upon an error.

http_referer_t * http_referer_dup	(	su_home_t *	home,
		http_referer_t const *	hdr
	)			[inline]

Duplicate (deep copy) http_referer_t.

The function http_referer_dup() duplicates 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

   referer = http_referer_dup(home, http->http_referer);

Returns:

The function http_referer_dup() returns a pointer to the newly duplicated http_referer_t header structure, or NULL upon an error.

http_referer_t * http_referer_format	(	su_home_t *	home,
		char const *	fmt,
			...
	)			[inline]

Make a Referer header from formatting result.

The function http_referer_format() makes a new Referer header 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 uses the formatting result as the header value.

Parameters:

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

Note:

This function is usually implemented as a macro calling msg_header_format().

Returns:

The function http_referer_format() returns a pointer to newly makes header structure, or NULL upon an error.

http_referer_t* http_referer_init

(

http_referer_t

x[1]

)

[inline]

Initialize a structure http_referer_t.

An http_referer_t structure can be initialized with the http_referer_init() function/macro. For instance,

  http_referer_t http_referer;

  http_referer_init(&http_referer);

http_referer_t * http_referer_make	(	su_home_t *	home,
		char const *	s
	)			[inline]

Make a header structure http_referer_t.

The function http_referer_make() makes a new http_referer_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

Note:

This function is usually implemented as a macro calling http_header_make().

Returns:

The function http_referer_make() returns a pointer to newly maked http_referer_t header structure, or NULL upon an error.

---

Variable Documentation

msg_hclass_t http_referer_class[]

Header class for HTTP Referer header.

The header class http_referer_class defines how a HTTP Referer header is parsed and printed. It also contains methods used by HTTP parser and other functions to manipulate the http_referer_t header structure.