Added the ability to clear out the DNS cache after a certain number of

insertions.
This commit is contained in:
Robert James Kaes 2001-09-07 00:40:34 +00:00
parent c24cace1d1
commit aa9e05430a

View File

@ -1,4 +1,4 @@
/* $Id: dnscache.c,v 1.12 2001-09-06 21:53:16 rjkaes Exp $ /* $Id: dnscache.c,v 1.13 2001-09-07 00:40:34 rjkaes Exp $
* *
* This is a caching DNS system. When a host name is needed we look it up here * This is a caching DNS system. When a host name is needed we look it up here
* and see if there is already an answer for it. The domains are placed in a * and see if there is already an answer for it. The domains are placed in a
@ -43,7 +43,7 @@ static pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;
#define UNLOCK() pthread_mutex_unlock(&mutex); #define UNLOCK() pthread_mutex_unlock(&mutex);
#define DNSEXPIRE (5 * 60) #define DNSEXPIRE (5 * 60)
#define DNS_INSERT_LIMIT 5 #define DNS_INSERT_LIMIT 10000 /* free the memory after inserts */
struct dnscache_s { struct dnscache_s {
struct in_addr ipaddr; struct in_addr ipaddr;
@ -80,8 +80,6 @@ static int dns_insert(struct in_addr *addr, char *domain)
assert(addr != NULL); assert(addr != NULL);
assert(domain != NULL); assert(domain != NULL);
DEBUG2("Inserting [%s] into DNS cache", domain);
if (!(newptr = malloc(sizeof(struct dnscache_s)))) { if (!(newptr = malloc(sizeof(struct dnscache_s)))) {
return -1; return -1;
} }
@ -89,11 +87,15 @@ static int dns_insert(struct in_addr *addr, char *domain)
memcpy(&newptr->ipaddr, addr, sizeof(struct in_addr)); memcpy(&newptr->ipaddr, addr, sizeof(struct in_addr));
newptr->expire = time(NULL); newptr->expire = time(NULL);
DEBUG2("Inserting [%s] into DNS cache", domain);
if (TE_ISERROR(ternary_replace(dns_tree, domain, newptr))) { if (TE_ISERROR(ternary_replace(dns_tree, domain, newptr))) {
safefree(newptr); safefree(newptr);
return -1; return -1;
} }
DEBUG2("Finished inserting [%s] into DNS cache", domain);
return 0; return 0;
} }
@ -136,7 +138,7 @@ int dnscache(struct in_addr *addr, char *domain)
dns_insertions++; dns_insertions++;
if (dns_insertions > DNS_INSERT_LIMIT) { if (dns_insertions > DNS_INSERT_LIMIT) {
log_message(LOG_NOTICE, "DNS Insertion limit, rebuilding cache."); log_message(LOG_NOTICE, "DNS Insertion limit, rebuilding cache.");
ternary_destroy(dns_tree, NULL); ternary_destroy(dns_tree, free);
dns_tree = ternary_new(); dns_tree = ternary_new();
dns_insertions = 0; dns_insertions = 0;
} }