//////////////////////////////////////
// initialize matching terms iterator
//
int DbIntlog::Search(Term t, DbEntryIter &iter, DbIntlog *dbs)
{
#ifdef _DEBUG
CCP tstring = t.get_funct();
#endif
DbEntry e = DbEntry(t.get_funct(), t.get_arity()),
*dbe = isin(e);
if (!dbe)
{
if (dbs == 0 ||
(dbe = dbs->isin(e)) == 0 ||
dbe->vProp != DbEntry::dynamic)
{
iter.pcc = 0;
iter.own = iter.mod = 0;
return 0;
}
iter.mod =
iter.own = dbs;
}
else
{
iter.mod = this;
iter.own = dbs;
}
// initialize for later search
iter.pcc = (e_DbList*)dbe->get_first()->fix_clause(dbs);
iter.pcp = 0;
return 1;
}
Term TermVisit::next()
{
if (size()) {
Term top = get();
pop();
if (top.type(f_STRUCT|f_LIST))
for (int n = top.get_arity() - 1; n >= 0; n--)
push(top.getarg(n));
return top;
}
return Term(f_NOTERM);
}
////////////////////////////////////
// resync clauses list
// this invalidate all DbEntryIter
//
void DbIntlog::ClearStatus(DbIntlog *owner)
{
slist_scan ld(m_deleted);
e_DbList *edbd;
while ((edbd = (e_DbList*)ld.next()) != 0)
{
Term tk = edbd->clause->get_head();
#ifdef _DEBUG
CCP tstring = tk.get_funct();
#endif
DbEntry x(tk.get_funct(), tk.get_arity());
DbEntry *dbe = isin(x);
ASSERT(dbe);
slist_scan tla(dbe->entries);
e_DbList *edbl;
while ((edbl = (e_DbList*)tla.next()) != 0)
if (edbl->clause == 0)
{
tla.delitem();
break;
}
if (!owner || edbd->type != e_DbList::tLocData ||
edbd->clause->get_db() == owner)
ld.delitem();
}
// clear all inherited DBs
DbInherIter it(this);
DbIntlog *db;
while ((db = (DbIntlog *)it.next()) != 0)
db->ClearStatus(this);
}
///////////////////////////////////
// storage entry point to database
//
void DbIntlog::Add(Clause *c, int first, DbIntlog *owner)
{
Term h = c->get_head();
ASSERT(!h.type(f_NOTERM));
#ifdef _DEBUG
CCP tstring = h.get_funct();
#endif
e_DbList *edbl = new e_DbList(c);
// retrieve or create the entry
kstring funct = h.get_funct();
int arity = h.get_arity();
DbEntry e(funct, arity), *dbe = isin(e);
// verify location on create
if (dbe == 0 && owner && owner != this)
dbe = owner->isin(e);
if (!dbe)
{
dbe = new DbEntry(funct, arity);
insert(dbe);
}
if (dbe->arity == -1)
dbe->arity = arity;
DbIntlog *dbwork = this;
if (dbe->vProp == DbEntry::dynamic)
{
if (!owner)
owner = this;
dbe = owner->isin(dbe);
ASSERT(dbe);
c->set_db(dbwork = owner);
}
else if (owner && owner != this)
{
edbl->type = e_DbList::tLocData;
c->set_db(owner);
}
if (first)
dbe->entries.insert(edbl, 0);
else
{
DbListSeek eref(e_DbList::tExtRef);
DbListSeek vtbl(e_DbList::tVTable);
unsigned iref = dbe->entries.seek(&eref);
unsigned itbl = dbe->entries.seek(&vtbl);
if (iref != SLIST_INVPOS)
dbe->entries.insert(edbl, iref);
else
if (itbl != SLIST_INVPOS)
dbe->entries.insert(edbl, itbl);
else
dbe->entries.append(edbl);
}
// close inheritance chainings
dbwork->check_inherited_entries(dbe);
}