DNS caching

Data Structures
struct	cache_entry
struct	wget_dns_cache_st

Functions
int	wget_dns_cache_init (wget_dns_cache **cache)
void	wget_dns_cache_free (wget_dns_cache **cache)
struct addrinfo *	wget_dns_cache_get (wget_dns_cache *cache, const char *host, uint16_t port)
int	wget_dns_cache_add (wget_dns_cache *cache, const char *host, uint16_t port, struct addrinfo **addrinfo)

Detailed Description

DNS cache management functions.

Function Documentation

wget_dns_cache_init()

int wget_dns_cache_init

(

wget_dns_cache **

cache

)

Parameters

[out]

cache

Pointer to return newly allocated and initialized wget_dns_cache instance

Returns

WGET_E_SUCCESS if OK, WGET_E_MEMORY if out-of-memory or WGET_E_INVALID if the mutex initialization failed.

Allocates and initializes a wget_dns_cache instance.

wget_dns_cache_free()

void wget_dns_cache_free

(

wget_dns_cache **

cache

)

Parameters

[in/out]

cache Pointer to wget_dns_cache instance that will be freed and NULLified.

Free the resources allocated by wget_dns_cache_init().

wget_dns_cache_get()

struct addrinfo * wget_dns_cache_get	(	wget_dns_cache *	cache,
		const char *	host,
		uint16_t	port )

Parameters

[in]	cache	A wget_dns_cache instance, created by wget_dns_cache_init().
[in]	host	Hostname to look up
[in]	port	Port to look up

Returns

The cached addrinfo structure or NULL if not found

wget_dns_cache_add()

int wget_dns_cache_add	(	wget_dns_cache *	cache,
		const char *	host,
		uint16_t	port,
		struct addrinfo **	addrinfo )

Parameters

[in]	cache	A wget_dns_cache instance, created by wget_dns_cache_init().
[in]	host	Hostname part of the key
[in]	port	Port part of the key
	[in/out]	addrinfo Addrinfo structure to cache, returns cached addrinfo

Returns

WGET_E_SUCCESS on success, else a WGET_E_* error value

This functions adds addrinfo to the given DNS cache cache.

If an entry for [host,port] already exists, addrinfo is free'd and replaced by the cached entry. Do not free addrinfo yourself - this will be done when the whole cache is freed.