GitLab

src/bin/dhcp4/ctrl_dhcp4_srv.*
src/bin/dhcp6/ctrl_dhcp6_srv.*
    Changed dbReconnect() to accept ReconnectCtlPtr
    Added commentary for dbReconnect and dbLostCallback

src/lib/dhcpsrv/database_connection.h
    Removed extraneous typedef

many files:
    Changed DatabaseConnection::Callback to ::DbLostCallback

src/lib/dhcpsrv/tests/database_connection_unittest.cc
    Added commentary to text fixture and tests

    kea-dhcp6
        added support for max-reconnect-tries and reconnect-wait-time
        to lease and host db parsers

        Added a callback for when DB backends detect loss of connectivity

        Added a self-rescheduling method to attempt to reconnect to the
        backends if retries are enabled

    dhcpsrv
        PgSqlConnection::checkStatementError() - Modified "fatal" logic
        to throw after invoking db_lost_callback.

    Misc. cleanup

kea-dhcp4
    added support for max-reconnect-tries and reconnect-wait-time
    to lease and host db parsers

    Added a callback for when DB backends detect loss of connectivity

    Added a self-rescheduling method to attempt to reconnect to the
    backends if retries are enabled

dhcpsrv
    Added a callback that DatabaseConnection derivations should invoke
    when they lose connectivity.

    Added an optional callback parameter from CfgDbAccess::createManagers()
    all the way down to DatabaseConnection ctor.

    pgsql_connection.cc
        PgSqlConnection::~PgSqlConnection() - Added logic to close the
        connection only when the connect state is still OK.
        Otherwise it likes to core dump.

        PgSqlConnection::checkStatementError() - Modified to invoke the
        connectivity lost callback on "fatal" errors

    pgsql_lease_mgr_unittest.cc
    pgsql_host_data_source_unittest.cc
        Added tests to verify that the lost callback is NOT invoked on an
        open failure

# Conflicts:
#	src/lib/dhcpsrv/tests/generic_host_data_source_unittest.cc

This change affects Memfile, MySQL and Postgres backend. These functions
aren't implemented for CQL at this time.