Retry-After header.

The Retry-After response-header field can be used with a 503 (Service Unavailable) response to indicate how long the service is expected to be unavailable to the requesting client. More...

Defines
#define	HTTP_RETRY_AFTER_INIT()
	Initializer for structure http_retry_after_t.
#define	HTTPTAG_RETRY_AFTER(x)
	Tag list item for pointer to a Retry-After header object.
#define	HTTPTAG_RETRY_AFTER_STR(s)
	Tag list item for string with Retry-After header value.
Typedefs
typedef struct http_retry_after_s	http_retry_after_t
	The structure http_retry_after_t contains representation of Retry-After header.
Enumerations
enum	{ http_retry_after_hash }
Functions
http_retry_after_t *	http_retry_after_init (http_retry_after_t x[1])
	Initialize a structure http_retry_after_t.
int	http_is_retry_after (http_header_t const *header)
	Test if header object is instance of http_retry_after_t.
http_retry_after_t *	http_retry_after_dup (su_home_t *home, http_retry_after_t const *hdr))
	Duplicate (deep copy) http_retry_after_t.
http_retry_after_t *	http_retry_after_copy (su_home_t *home, http_retry_after_t const *hdr))
	Copy a http_retry_after_t header structure.
http_retry_after_t *	http_retry_after_make (su_home_t *home, char const *s))
	Make a header structure http_retry_after_t.
http_retry_after_t *	http_retry_after_format (su_home_t *home, char const *fmt,...)))
	Make a Retry-After header from formatting result.
Variables
msg_hclass_t	http_retry_after_class []
	Header class for HTTP Retry-After header.
msg_parse_f	http_retry_after_d
	Decode (parse) a Retry-After header.
msg_print_f	http_retry_after_e
	Encode (print) a Retry-After header.

---

Detailed Description

The Retry-After response-header field can be used with a 503 (Service Unavailable) response to indicate how long the service is expected to be unavailable to the requesting client.

This field MAY also be used with any 3xx (Redirection) response to indicate the minimum time the user-agent is asked wait before issuing the redirected request. Its syntax is defined in RFC 2616 section 14.37 as follows:

    Retry-After   =  "Retry-After" ":" ( HTTP-date / delta-seconds )

---

Define Documentation

#define HTTP_RETRY_AFTER_INIT

(

)

Initializer for structure http_retry_after_t.

A static http_retry_after_t structure must be initialized with the HTTP_RETRY_AFTER_INIT() macro. For instance,

  http_retry_after_t http_retry_after = HTTP_RETRY_AFTER_INIT;

#define HTTPTAG_RETRY_AFTER

(

x

)

Tag list item for pointer to a Retry-After header object.

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

Parameters:

x

pointer to a http_retry_after_t header structure, or NULL.

#define HTTPTAG_RETRY_AFTER_STR

(

s

)

Tag list item for string with Retry-After header value.

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

Parameters:

s

pointer to a string containing http_retry_after_t value, or NULL.

The HTTPTAG_RETRY_AFTER_STR string can be converted to a http_retry_after_t header structure by giving the string s has second argument to function http_retry_after_make().

---

Typedef Documentation

typedef struct http_retry_after_s http_retry_after_t

The structure http_retry_after_t contains representation of Retry-After header.

The http_retry_after_t is defined as follows:

 typedef struct {
   msg_common_t         ra_common[1]; // Common fragment info
   msg_error_t         *ra_next;      // Link to next (dummy)
   http_time_t          ra_date;      // When to retry
   http_time_t          ra_delta;     // Seconds to before retry
 } http_retry_after_t;

---

Enumeration Type Documentation

anonymous enum

Enumerator:

http_retry_after_hash

Hash of Retry-After header.

---

Function Documentation

int http_is_retry_after

(

http_header_t const *

header

)

[inline]

Test if header object is instance of http_retry_after_t.

The function http_is_retry_after() returns true (nonzero) if the header class is an instance of Retry-After header object and false (zero) otherwise.

Parameters:

header

pointer to the header structure to be tested

Returns:

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

http_retry_after_t * http_retry_after_copy	(	su_home_t *	home,
		http_retry_after_t const *	hdr
	)			[inline]

Copy a http_retry_after_t header structure.

The function http_retry_after_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

   retry_after = http_retry_after_copy(home, http->http_retry_after);

Returns:

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

http_retry_after_t * http_retry_after_dup	(	su_home_t *	home,
		http_retry_after_t const *	hdr
	)			[inline]

Duplicate (deep copy) http_retry_after_t.

The function http_retry_after_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

   retry_after = http_retry_after_dup(home, http->http_retry_after);

Returns:

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

http_retry_after_t * http_retry_after_format	(	su_home_t *	home,
		char const *	fmt,
			...
	)			[inline]

Make a Retry-After header from formatting result.

The function http_retry_after_format() makes a new Retry-After 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_retry_after_format() returns a pointer to newly makes header structure, or NULL upon an error.

http_retry_after_t* http_retry_after_init

(

http_retry_after_t

x[1]

)

[inline]

Initialize a structure http_retry_after_t.

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

  http_retry_after_t http_retry_after;

  http_retry_after_init(&http_retry_after);

http_retry_after_t * http_retry_after_make	(	su_home_t *	home,
		char const *	s
	)			[inline]

Make a header structure http_retry_after_t.

The function http_retry_after_make() makes a new http_retry_after_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_retry_after_make() returns a pointer to newly maked http_retry_after_t header structure, or NULL upon an error.

---

Variable Documentation

msg_hclass_t http_retry_after_class[]

Header class for HTTP Retry-After header.

The header class http_retry_after_class defines how a HTTP Retry-After header is parsed and printed. It also contains methods used by HTTP parser and other functions to manipulate the http_retry_after_t header structure.