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Add support for negative cache entries to add().

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This commit is contained in:
Bob Halley
1999-10-16 00:49:33 +00:00
parent 3706171484
commit 1aaa8e40df
1 changed files with 53 additions and 14 deletions
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67
lib/dns/rbtdb.c
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@@ -2857,7 +2857,7 @@ add(dns_rbtdb_t *rbtdb, dns_rbtnode_t *rbtnode, rbtdb_version_t *rbtversion,
isc_boolean_t force = ISC_FALSE;
isc_boolean_t header_nx;
isc_boolean_t newheader_nx;
dns_rdatatype_t nxtype;
dns_rdatatype_t nxtype, rdtype, covers;
/*
* Add an rdatasetheader_t to a node.
@@ -2881,17 +2881,17 @@ add(dns_rbtdb_t *rbtdb, dns_rbtnode_t *rbtnode, rbtdb_version_t *rbtversion,
}
newheader_nx = NONEXISTENT(newheader) ? ISC_TRUE : ISC_FALSE;
topheader_prev = NULL;
nxtype = 0;
#ifdef notyet
if (rbtversion == NULL) {
if (RBTDB_RDATASET_BASE(newheader->type) == 0
&& !newheader_nx) {
if (rbtversion == NULL && !newheader_nx) {
rdtype = RBTDB_RDATATYPE_BASE(newheader->type);
if (rdtype == 0) {
/*
* We're adding a negative cache entry.
*/
if (RBTDB_RDATASET_EXT(newheader->type) ==
dns_rdatatype_any) {
covers = RBTDB_RDATATYPE_EXT(newheader->type);
if (covers == dns_rdatatype_any) {
/*
* We're adding an NXDOMAIN negative cache
* entry.
@@ -2910,12 +2910,51 @@ add(dns_rbtdb_t *rbtdb, dns_rbtnode_t *rbtnode, rbtdb_version_t *rbtversion,
rbtnode->dirty = 1;
goto find_header;
}
nxtype = ;
nxtype = RBTDB_RDATATYPE_VALUE(covers, 0);
} else {
/*
* We're adding something that isn't a
* negative cache entry. Look for an extant
* non-stale NXDOMAIN negative cache entry.
*/
for (topheader = rbtnode->data;
topheader != NULL;
topheader = topheader->next) {
if (topheader->type ==
RBTDB_RDATATYPE_NXDOMAIN)
break;
}
if (topheader != NULL && EXISTS(topheader) &&
topheader->ttl > now) {
/*
* Found one.
*/
if (newheader->trust < topheader->trust) {
/*
* The NXDOMAIN is more trusted.
*/
free_rdataset(rbtdb->common.mctx,
newheader);
if (addedrdataset != NULL)
bind_rdataset(rbtdb, rbtnode,
topheader, now,
addedrdataset);
return (DNS_R_UNCHANGED);
}
/*
* The new rdataset is better. Expire the
* NXDOMAIN.
*/
topheader->ttl = 0;
topheader->attributes |= RDATASET_ATTR_STALE;
rbtnode->dirty = 1;
topheader = NULL;
goto find_header;
}
nxtype = RBTDB_RDATATYPE_VALUE(0, rdtype);
}
}
#endif
topheader_prev = NULL;
for (topheader = rbtnode->data;
topheader != NULL;
topheader = topheader->next) {
@@ -2924,9 +2963,8 @@ add(dns_rbtdb_t *rbtdb, dns_rbtnode_t *rbtnode, rbtdb_version_t *rbtversion,
break;
topheader_prev = topheader;
}
#ifdef notyet
find_header:
#endif
/*
* If header isn't NULL, we've found the right type. There may be
* IGNORE rdatasets between the top of the chain and the first real
@@ -2948,9 +2986,10 @@ add(dns_rbtdb_t *rbtdb, dns_rbtnode_t *rbtnode, rbtdb_version_t *rbtversion,
/*
* Trying to add an rdataset with lower trust to a cache DB
* has no effect.
* has no effect, provided that the cache data isn't stale.
*/
if (rbtversion == NULL && newheader->trust < header->trust) {
if (rbtversion == NULL && newheader->trust < header->trust &&
(header->ttl > now || header_nx)) {
free_rdataset(rbtdb->common.mctx, newheader);
if (addedrdataset != NULL)
bind_rdataset(rbtdb, rbtnode, header, now,