1 files changed, 105 insertions, 0 deletions
diff --git a/src/lib/dns/rrcollator.cc b/src/lib/dns/rrcollator.cc
new file mode 100644
index 0000000..8378021
--- /dev/null
+++ b/src/lib/dns/rrcollator.cc
@@ -0,0 +1,105 @@
+// Copyright (C) 2012-2020 Internet Systems Consortium, Inc. ("ISC")
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+#include <config.h>
+
+#include <exceptions/exceptions.h>
+
+// include this first to check the header is self-contained.
+#include <dns/rrcollator.h>
+
+#include <dns/name.h>
+#include <dns/rdataclass.h>
+#include <dns/rrclass.h>
+#include <dns/rrtype.h>
+#include <dns/rrttl.h>
+#include <dns/rdata.h>
+#include <dns/rrset.h>
+
+#include <algorithm>
+#include <functional>
+
+using namespace isc::dns::rdata;
+namespace ph = std::placeholders;
+
+namespace isc {
+namespace dns {
+
+class RRCollator::Impl {
+public:
+    Impl(const AddRRsetCallback& callback) : callback_(callback) {}
+
+    void addRR(const Name& name, const RRClass& rrclass,
+               const RRType& rrtype, const RRTTL& rrttl,
+               const RdataPtr& rdata);
+
+    RRsetPtr current_rrset_;
+    const AddRRsetCallback callback_;
+};
+
+namespace {
+inline bool
+isSameType(RRType type1, const ConstRdataPtr& rdata1,
+           const ConstRRsetPtr& rrset)
+{
+    if (type1 != rrset->getType()) {
+        return (false);
+    }
+    if (type1 == RRType::RRSIG()) {
+        RdataIteratorPtr rit = rrset->getRdataIterator();
+        return (dynamic_cast<const generic::RRSIG&>(*rdata1).typeCovered()
+                == dynamic_cast<const generic::RRSIG&>(
+                    rit->getCurrent()).typeCovered());
+    }
+    return (true);
+}
+}
+
+void
+RRCollator::Impl::addRR(const Name& name, const RRClass& rrclass,
+                        const RRType& rrtype, const RRTTL& rrttl,
+                        const RdataPtr& rdata)
+{
+    if (current_rrset_ && (!isSameType(rrtype, rdata, current_rrset_) ||
+                           current_rrset_->getClass() != rrclass ||
+                           current_rrset_->getName() != name)) {
+        callback_(current_rrset_);
+        current_rrset_.reset();
+    }
+
+    if (!current_rrset_) {
+        current_rrset_ = RRsetPtr(new RRset(name, rrclass, rrtype, rrttl));
+    } else if (current_rrset_->getTTL() != rrttl) {
+        // RRs with different TTLs are given.  Smaller TTL should win.
+        current_rrset_->setTTL(std::min(current_rrset_->getTTL(), rrttl));
+    }
+    current_rrset_->addRdata(rdata);
+}
+
+RRCollator::RRCollator(const AddRRsetCallback& callback) :
+    impl_(new Impl(callback))
+{}
+
+RRCollator::~RRCollator() {
+    delete impl_;
+}
+
+AddRRCallback
+RRCollator::getCallback() {
+    return (std::bind(&RRCollator::Impl::addRR, this->impl_,
+                      ph::_1, ph::_2, ph::_3, ph::_4, ph::_5));
+}
+
+void
+RRCollator::flush() {
+    if (impl_->current_rrset_) {
+        impl_->callback_(impl_->current_rrset_);
+        impl_->current_rrset_.reset();
+    }
+}
+
+} // end namespace dns
+} // end namespace isc