If-Range header.

The If-Range header is used when a client has a partial copy of an entity in its cache, and wishes to have an up-to-date copy of the entire entity. More...

Defines
#define	HTTP_IF_RANGE_INIT()
	Initializer for structure http_if_range_t.
#define	HTTPTAG_IF_RANGE(x)
	Tag list item for pointer to a If-Range header object.
#define	HTTPTAG_IF_RANGE_STR(s)
	Tag list item for string with If-Range header value.
Enumerations
enum	{ http_if_range_hash }
Functions
http_if_range_t *	http_if_range_init (http_if_range_t x[1])
	Initialize a structure http_if_range_t.
int	http_is_if_range (http_header_t const *header)
	Test if header object is instance of http_if_range_t.
http_if_range_t *	http_if_range_dup (su_home_t *home, http_if_range_t const *hdr))
	Duplicate (deep copy) http_if_range_t.
http_if_range_t *	http_if_range_copy (su_home_t *home, http_if_range_t const *hdr))
	Copy a http_if_range_t header structure.
http_if_range_t *	http_if_range_make (su_home_t *home, char const *s))
	Make a header structure http_if_range_t.
http_if_range_t *	http_if_range_format (su_home_t *home, char const *fmt,...)))
	Make a If-Range header from formatting result.
Variables
msg_hclass_t	http_if_range_class []
	Header class for HTTP If-Range header.
msg_parse_f	http_if_range_d
	Decode (parse) a If-Range header.
msg_print_f	http_if_range_e
	Encode (print) a If-Range header.

---

Detailed Description

The If-Range header is used when a client has a partial copy of an entity in its cache, and wishes to have an up-to-date copy of the entire entity.

Informally, its meaning is `if the entity is unchanged, send me the part(s) that I am missing; otherwise, send me the entire new entity'. Its syntax is defined in RFC 2616 as follows:

   If-Range = "If-Range" ":" ( entity-tag / HTTP-date )

---

Define Documentation

#define HTTP_IF_RANGE_INIT

(

)

Initializer for structure http_if_range_t.

A static http_if_range_t structure must be initialized with the HTTP_IF_RANGE_INIT() macro. For instance,

  http_if_range_t http_if_range = HTTP_IF_RANGE_INIT;

#define HTTPTAG_IF_RANGE

(

x

)

Tag list item for pointer to a If-Range header object.

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

Parameters:

x

pointer to a http_if_range_t header structure, or NULL.

#define HTTPTAG_IF_RANGE_STR

(

s

)

Tag list item for string with If-Range header value.

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

Parameters:

s

pointer to a string containing http_if_range_t value, or NULL.

The HTTPTAG_IF_RANGE_STR string can be converted to a http_if_range_t header structure by giving the string s has second argument to function http_if_range_make().

---

Enumeration Type Documentation

anonymous enum

Enumerator:

http_if_range_hash

Hash of If-Range header.

---

Function Documentation

http_if_range_t * http_if_range_copy	(	su_home_t *	home,
		http_if_range_t const *	hdr
	)			[inline]

Copy a http_if_range_t header structure.

The function http_if_range_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

   if_range = http_if_range_copy(home, http->http_if_range);

Returns:

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

http_if_range_t * http_if_range_dup	(	su_home_t *	home,
		http_if_range_t const *	hdr
	)			[inline]

Duplicate (deep copy) http_if_range_t.

The function http_if_range_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

   if_range = http_if_range_dup(home, http->http_if_range);

Returns:

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

http_if_range_t * http_if_range_format	(	su_home_t *	home,
		char const *	fmt,
			...
	)			[inline]

Make a If-Range header from formatting result.

The function http_if_range_format() makes a new If-Range 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_if_range_format() returns a pointer to newly makes header structure, or NULL upon an error.

http_if_range_t* http_if_range_init

(

http_if_range_t

x[1]

)

[inline]

Initialize a structure http_if_range_t.

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

  http_if_range_t http_if_range;

  http_if_range_init(&http_if_range);

http_if_range_t * http_if_range_make	(	su_home_t *	home,
		char const *	s
	)			[inline]

Make a header structure http_if_range_t.

The function http_if_range_make() makes a new http_if_range_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_if_range_make() returns a pointer to newly maked http_if_range_t header structure, or NULL upon an error.

int http_is_if_range

(

http_header_t const *

header

)

[inline]

Test if header object is instance of http_if_range_t.

The function http_is_if_range() returns true (nonzero) if the header class is an instance of If-Range header object and false (zero) otherwise.

Parameters:

header

pointer to the header structure to be tested

Returns:

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

---

Variable Documentation

msg_hclass_t http_if_range_class[]

Header class for HTTP If-Range header.

The header class http_if_range_class defines how a HTTP If-Range header is parsed and printed. It also contains methods used by HTTP parser and other functions to manipulate the http_if_range_t header structure.