/*
* Copyright (c) 1987,1988 Massachusetts Institute of Technology.
*
* Note that there is absolutely NO WARRANTY on this software.
* See the file COPYRIGHT.NOTICE for details and restrictions.
*
* Garbage collector. Not particularly clever, not ephemeral.
* I suppose lookup() could be haired up to do ephemeral if
* it becomes an issue, which I doubt.
*/
#include "domsym.h"
#define punt(arg) return(bugchk arg, 0)
int gc(zones,cache,ncache)
struct btnode **zones, **cache, **ncache;
{
struct btnode *old, *new;
int gc_zones(), gc_cache(), gc_ncache();
char *vector[MAX_DOMAIN_TAG_COUNT+1];
int now = zulu();
old = *zones; new = NULL;
if(!gctree(old,&new,gc_zones,vector+MAX_DOMAIN_TAG_COUNT+1,0,now))
bughlt("gc","gc of zones failed");
*zones = new; kil_btnode(old,NULL);
old = *cache; new = NULL;
if(!gctree(old,&new,gc_cache,vector+MAX_DOMAIN_TAG_COUNT+1,0,now))
bughlt("gc","gc of cache failed");
*cache = new; kil_btnode(old,NULL);
old = *ncache; new = NULL;
if(!gctree(old,&new,gc_ncache,vector+MAX_DOMAIN_TAG_COUNT+1,0,now))
bughlt("gc","gc of ncache failed");
*ncache = new; kil_btnode(old,NULL);
return(1);
}
static int gctree(old_tree,new_tree,func,vector,ntags,now)
struct btnode *old_tree, **new_tree;
int (*func)(), ntags, now;
char **vector;
{
if(old_tree == NULL)
return(1);
if(new_tree == NULL || func == NULL || vector == NULL)
punt(("gctree","new_tree=%o, func=%o, vector=%o",
new_tree, func, vector));
if(DBGFLG(DBG_GC)) {
char *name = namimp(vector,ntags), rrtext[STRSIZ];
if(namtoa(rrtext,name) == NULL)
rrtext[0] = '\0';
buginf("gctree","old_tree=%o, *new_tree=%o, ntags=%d, name=\"%s\"",
old_tree,*new_tree,ntags,rrtext);
if(name != NULL)
kil(name);
}
if(!gcnode(old_tree,new_tree,func,--vector,++ntags,now))
punt(("gctree","gcnode() failed"));
return(1);
}
static int gcnode(old_node,new_tree,func,vector,ntags,now)
struct btnode *old_node, **new_tree;
char **vector;
int ntags, now, (*func)();
{
if(old_node == NULL)
return(1);
if(new_tree == NULL || vector == NULL || func == NULL)
punt(("gcnode","new_tree=%o, vector=%o, func=%o",
new_tree, vector, func));
if((*vector = old_node->data.name) == NULL)
punt(("gcnode","null name"));
if(DBGFLG(DBG_GC)) {
char *name = namimp(vector,ntags), rrtext[STRSIZ];
buginf("gcnode","old_node=%o, old_node->tpoint=%o, old_node->left=%o, old_node->right=%o",old_node, old_node->data.link.tpoint, old_node->left, old_node->right);
buginf("gcnode","new_tree=%o, *new_tree=%o, ntags=%d, name=\"%s\"",
new_tree, *new_tree, ntags, namtoa(rrtext,name));
if(name != NULL)
kil(name);
}
if(!(*func)(old_node,new_tree,vector,ntags,now))
punt(("gcnode","func failed"));
if(!gctree(old_node->data.link.tpoint,new_tree,func,vector,ntags,now))
punt(("gcnode","nested gctree() failed"));
if(!gcnode(old_node->left,new_tree,func,vector,ntags,now))
punt(("gcnode","nested gcnode(left) failed"));
if(!gcnode(old_node->right,new_tree,func,vector,ntags,now))
punt(("gcnode","nested gcnode(right) failed"));
return(1);
}
/* Macro to snip an entry out of a list and append it to another list. */
#define FIFO_append(list_tail,node_var,link_tag) { \
node_var = (*list_tail = node_var)->link_tag; \
*(list_tail = &((*list_tail)->link_tag)) = NULL;\
}
static int gc_zones(node,tree,vector,ntags,now)
struct btnode *node, **tree;
char **vector;
int ntags, now;
{
struct zone *z;
struct zone *keep_head = NULL, **keep_tail = &keep_head;
struct zone *kill_head = NULL, **kill_tail = &kill_head;
if(node == NULL)
return(1);
if(tree == NULL || vector == NULL)
punt(("gc_zones","tree=%o, vector=%o",tree,vector));
z = node->data.data.zoa;
while(z != NULL) {
if(DBGFLG(DBG_GC))
buginf("gc_zones",
"z=%o, gotten=%d, soa_expire=%d, gotten+soa_expire=%d, now=%d",
z, z->gotten, z->base.data.rrs->rdata[SOA_EXPIRE].word,
z->gotten + z->base.data.rrs->rdata[SOA_EXPIRE].word, now);
if( z->gotten == 0 /* zero means never GC */
|| z->gotten + z->base.data.rrs->rdata[SOA_EXPIRE].word > now) {
if(DBGFLG(DBG_GC))
buginf("gc_zones","keeping z=%o",z);
FIFO_append(keep_tail,z,next) /* ; */
} else {
if(DBGFLG(DBG_GC))
buginf("gc_zones","killing z=%o",z);
FIFO_append(kill_tail,z,next) /* ; */
}
}
if(keep_head != NULL) {
char *name = namimp(vector,ntags);
if(!insert(tree,name,keep_head,0,0))
punt(("gc_zones","failed to re-insert zone"));
kil(name);
}
kil_zone(kill_head);
node->data.data.zoa = NULL;
return(1);
}
static int gc_cache(node,tree,vector,ntags,now)
struct btnode *node, **tree;
char **vector;
int ntags, now;
{
struct rr *r;
struct rr *keep_head = NULL, **keep_tail = &keep_head;
struct rr *kill_head = NULL, **kill_tail = &kill_head;
if(node == NULL)
return(1);
if(tree == NULL || vector == NULL)
punt(("gc_cache","tree=%o, vector=%o",tree,vector));
r = node->data.data.rrs;
while(r != NULL)
if(r->ttl > now) {
if(DBGFLG(DBG_GC))
buginf("gc_cache","keeping r=%o",r);
FIFO_append(keep_tail,r,chain) /* ; */
} else {
if(DBGFLG(DBG_GC))
buginf("gc_cache","killing r=%o",r);
FIFO_append(kill_tail,r,chain) /* ; */
}
if(keep_head != NULL) {
char *name = namimp(vector,ntags);
if(!insert(tree,name,keep_head,0,1))
punt(("gc_cache","failed to re-insert RRs"));
kil(name);
}
kil_rr(kill_head);
node->data.data.rrs = NULL;
return(1);
}
static int gc_ncache(node,tree,vector,ntags,now)
struct btnode *node, **tree;
char **vector;
int ntags, now;
{
struct rr *r, *t;
struct rr *keep_head = NULL, **keep_tail = &keep_head;
struct rr *kill_head = NULL, **kill_tail = &kill_head;
if(node == NULL)
return(1);
if(tree == NULL || vector == NULL)
punt(("gc_ncache","tree=%o, vector=%o",tree,vector));
r = node->data.data.rrs;
while(r != NULL)
if(r->ttl > now) {
if(DBGFLG(DBG_GC))
buginf("gc_ncache","keeping r=%o",r);
FIFO_append(keep_tail,r,chain) /* ; */
} else {
if(DBGFLG(DBG_GC))
buginf("gc_ncache","killing r=%o",r);
FIFO_append(kill_tail,r,chain) /* ; */
}
if(keep_head != NULL) {
char *name = namimp(vector,ntags);
if(!insert(tree,name,keep_head,0,0))
punt(("gc_ncache","failed to re-insert RRs"));
kil(name);
}
r = kill_head; /* not exactly RRs, kill by hand */
while(r != NULL) {
r = (t = r)->chain;
kil_(t->rdata);
kil_(t);
}
node->data.data.rrs = NULL;
return(1);
}