Unable to build from .src.rpm - oc_package_header etc problems



I’d like to build the client from owncloud-client-2.4.2-9883.1.src.rpm so that it will use the system Qt5 rather than its own version, but I can’t work out where the definitions of _oc_package_header and other macros used in the spec files are supposed to come from. Presumably there’s a package that installs /etc/rpm/macros.owncloud or similar, but I can’t find any reference to it in the documentation nor any likely-looking package in the repo.

OS is Scientific Linux 7.4
.src.rpm downloaded from http://download.opensuse.org/repositories/isv:/ownCloud:/desktop/CentOS_7/src/