DNS cache definitions. More...

Detailed Description

DNS cache definitions.

This implements a simple DNS cache for A and AAAA entries.

The cache eviction strategy is based on the remaining time to live of the cache entries, so the first entry to expire will be evicted.

This is fine if there are only few cache entries and cache eviction is unlikely. If there is communication to many different hosts, the addition of a least-recently used counter could likely improve the behavior.

Author: Benjamin Valentin benja.nosp@m.min..nosp@m.valen.nosp@m.tin@.nosp@m.ml-pa.nosp@m..com

Definition in file cache.h.

#include <stdint.h>
#include "modules.h"

Include dependency graph for cache.h:

Go to the source code of this file.

Macros
#define	CONFIG_DNS_CACHE_SIZE 4
	Maximum number of DNS cache entries.

#define	CONFIG_DNS_CACHE_A IS_USED(MODULE_IPV4)
	Handle to cache A records.

#define	CONFIG_DNS_CACHE_AAAA IS_USED(MODULE_IPV6)
	Handle to cache AAAA records.

Functions
int	dns_cache_query (const char domain_name, void addr_out, int family)
	Get IP address for a DNS name from the DNS cache.

void	dns_cache_add (const char domain_name, const void addr, int addr_len, uint32_t ttl)
	Add an IP address for a DNS name to the DNS cache.

Detailed Description

Macros

Functions