1 files changed, 108 insertions, 0 deletions
diff --git a/src/lib/dhcpsrv/cfg_db_access.cc b/src/lib/dhcpsrv/cfg_db_access.cc
new file mode 100644
index 0000000..dd843a9
--- /dev/null
+++ b/src/lib/dhcpsrv/cfg_db_access.cc
@@ -0,0 +1,108 @@
+// Copyright (C) 2016-2020 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 <dhcpsrv/cfg_db_access.h>
+#include <dhcpsrv/db_type.h>
+#include <dhcpsrv/host_data_source_factory.h>
+#include <dhcpsrv/host_mgr.h>
+#include <dhcpsrv/lease_mgr_factory.h>
+#include <boost/algorithm/string.hpp>
+#include <boost/foreach.hpp>
+#include <boost/lexical_cast.hpp>
+#include <sstream>
+#include <vector>
+
+using namespace isc::data;
+
+namespace isc {
+namespace dhcp {
+
+CfgDbAccess::CfgDbAccess()
+    : appended_parameters_(), lease_db_access_("type=memfile"),
+      host_db_access_(), ip_reservations_unique_(true) {
+}
+
+std::string
+CfgDbAccess::getLeaseDbAccessString() const {
+    return (getAccessString(lease_db_access_));
+}
+
+
+std::string
+CfgDbAccess::getHostDbAccessString() const {
+    if (host_db_access_.empty()) {
+        return ("");
+    } else {
+        return (getAccessString(host_db_access_.front()));
+    }
+}
+
+std::list<std::string>
+CfgDbAccess::getHostDbAccessStringList() const {
+    std::list<std::string> ret;
+    for (const std::string& dbaccess : host_db_access_) {
+        if (!dbaccess.empty()) {
+            ret.push_back(getAccessString(dbaccess));
+        }
+    }
+    return (ret);
+}
+
+void
+CfgDbAccess::createManagers() const {
+    // Recreate lease manager.
+    LeaseMgrFactory::destroy();
+    LeaseMgrFactory::create(getLeaseDbAccessString());
+
+    // Recreate host data source.
+    HostMgr::create();
+
+    // Restore the host cache.
+    if (HostDataSourceFactory::registeredFactory("cache")) {
+        HostMgr::addBackend("type=cache");
+    }
+
+    // Add database backends.
+    std::list<std::string> host_db_access_list = getHostDbAccessStringList();
+    for (std::string& hds : host_db_access_list) {
+        HostMgr::addBackend(hds);
+    }
+
+    // Check for a host cache.
+    HostMgr::checkCacheBackend(true);
+
+    // Populate the ip-reservations-unique global setting to HostMgr.
+    // This operation may fail if any of the host backends does not support
+    // the new setting. We throw an exception here to signal configuration
+    // error. The exception does not contain the backend name but the called
+    // function in HostMgr logs a warning message that contains the name of
+    // the backend.
+    if (!HostMgr::instance().setIPReservationsUnique(ip_reservations_unique_)) {
+        isc_throw(InvalidOperation, "unable to configure the server to allow "
+                  "non unique IP reservations (ip-reservations-unique=false) "
+                  "because some host backends in use do not support this "
+                  "setting");
+    }
+}
+
+std::string
+CfgDbAccess::getAccessString(const std::string& access_string) const {
+    std::ostringstream s;
+    s << access_string;
+    // Only append additional parameters if any parameters are specified
+    // in a configuration. For host database, no parameters mean that
+    // database access is disabled and thus we don't want to append any
+    // parameters.
+    if ((s.tellp() != std::streampos(0)) && (!appended_parameters_.empty())) {
+        s << " " << appended_parameters_;
+    }
+
+    return (s.str());
+}
+
+} // end of isc::dhcp namespace
+} // end of isc namespace