Expires header.

The Expires header field gives the date and time after which the message content expires. More...

Defines
#define	HTTP_EXPIRES_INIT()
	Initializer for structure http_expires_t.
#define	HTTPTAG_EXPIRES(x)
	Tag list item for pointer to a Expires header object.
#define	HTTPTAG_EXPIRES_STR(s)
	Tag list item for string with Expires header value.
Typedefs
typedef http_date_t	http_expires_t
	The structure http_expires_t contains representation of Expires header.
Enumerations
enum	{ http_expires_hash }
Functions
http_expires_t *	http_expires_init (http_expires_t x[1])
	Initialize a structure http_expires_t.
int	http_is_expires (http_header_t const *header)
	Test if header object is instance of http_expires_t.
http_expires_t *	http_expires_dup (su_home_t *home, http_expires_t const *hdr))
	Duplicate (deep copy) http_expires_t.
http_expires_t *	http_expires_copy (su_home_t *home, http_expires_t const *hdr))
	Copy a http_expires_t header structure.
http_expires_t *	http_expires_make (su_home_t *home, char const *s))
	Make a header structure http_expires_t.
http_expires_t *	http_expires_format (su_home_t *home, char const *fmt,...)))
	Make a Expires header from formatting result.
Variables
msg_hclass_t	http_expires_class []
	Header class for HTTP Expires header.
msg_parse_f	http_expires_d
	Decode (parse) a Expires header.
msg_print_f	http_expires_e
	Encode (print) a Expires header.

---

Detailed Description

The Expires header field gives the date and time after which the message content expires.

Its syntax is defined in RFC 1428 section 14.21 as follows:

    Expires     =  "Expires:" HTTP-date

---

Define Documentation

#define HTTP_EXPIRES_INIT

(

)

Initializer for structure http_expires_t.

A static http_expires_t structure must be initialized with the HTTP_EXPIRES_INIT() macro. For instance,

  http_expires_t http_expires = HTTP_EXPIRES_INIT;

#define HTTPTAG_EXPIRES

(

x

)

Tag list item for pointer to a Expires header object.

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

Parameters:

x

pointer to a http_expires_t header structure, or NULL.

#define HTTPTAG_EXPIRES_STR

(

s

)

Tag list item for string with Expires header value.

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

Parameters:

s

pointer to a string containing http_expires_t value, or NULL.

The HTTPTAG_EXPIRES_STR string can be converted to a http_expires_t header structure by giving the string s has second argument to function http_expires_make().

---

Typedef Documentation

typedef struct http_expires_s http_expires_t

The structure http_expires_t contains representation of Expires header.

The http_expires_t is defined as follows:

 typedef struct {
   msg_common_t    d_common[1];        // Common fragment info
   msg_error_t    *d_next;             // Link to next (dummy)
   http_time_t     d_time;             // Seconds since Jan 1, 1900
 } http_expires_t;

---

Enumeration Type Documentation

anonymous enum

Enumerator:

http_expires_hash

Hash of Expires header.

---

Function Documentation

http_expires_t * http_expires_copy	(	su_home_t *	home,
		http_expires_t const *	hdr
	)			[inline]

Copy a http_expires_t header structure.

The function http_expires_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

   expires = http_expires_copy(home, http->http_expires);

Returns:

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

http_expires_t * http_expires_dup	(	su_home_t *	home,
		http_expires_t const *	hdr
	)			[inline]

Duplicate (deep copy) http_expires_t.

The function http_expires_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

   expires = http_expires_dup(home, http->http_expires);

Returns:

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

http_expires_t * http_expires_format	(	su_home_t *	home,
		char const *	fmt,
			...
	)			[inline]

Make a Expires header from formatting result.

The function http_expires_format() makes a new Expires 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_expires_format() returns a pointer to newly makes header structure, or NULL upon an error.

http_expires_t* http_expires_init

(

http_expires_t

x[1]

)

[inline]

Initialize a structure http_expires_t.

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

  http_expires_t http_expires;

  http_expires_init(&http_expires);

http_expires_t * http_expires_make	(	su_home_t *	home,
		char const *	s
	)			[inline]

Make a header structure http_expires_t.

The function http_expires_make() makes a new http_expires_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_expires_make() returns a pointer to newly maked http_expires_t header structure, or NULL upon an error.

int http_is_expires

(

http_header_t const *

header

)

[inline]

Test if header object is instance of http_expires_t.

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

Parameters:

header

pointer to the header structure to be tested

Returns:

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

---

Variable Documentation

msg_hclass_t http_expires_class[]

Header class for HTTP Expires header.

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