$ git clone -n https://gitee.com/src-opencloudos-rpms/libpng.git /var/lib/mock/dist-oc8-build-233063-81791/root/chroot_tmpdir/scmroot/libpng
Cloning into '/var/lib/mock/dist-oc8-build-233063-81791/root/chroot_tmpdir/scmroot/libpng'...
$ git fetch origin ff4f2f34418008dcf594332c027ddabc86741127:KOJI_FETCH_HEAD
From https://gitee.com/src-opencloudos-rpms/libpng
 * [new ref]         ff4f2f34418008dcf594332c027ddabc86741127 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at ff4f2f3 import libpng-1.6.34-9.tl3