Clone their helper repo first:
git clone https://git.centos.org/git/centos-git-common.git
Go to their RPM project and
select a project to clone. I’m picking
coreutils here. This repo has
a SPEC file and the patches to the original source.
git clone https://git.centos.org/r/rpms/coreutils.git
The master branch is always empty. Checkout their
c7 branch to see
the SPECS and SOURCES folders for Centos 7, and run the helper script
to fetch the source.
git checkout c7 ../centos-git-common/get_sources.sh