$ git clone -n https://gitee.com/leacyand/ffmpeg.git /var/lib/mock/dist-an23-epao-build-552261-88935/root/chroot_tmpdir/scmroot/ffmpeg
Cloning into '/var/lib/mock/dist-an23-epao-build-552261-88935/root/chroot_tmpdir/scmroot/ffmpeg'...
$ git fetch origin 6b76fb83fd8633e868eb72b55869fc2421bbaf38:KOJI_FETCH_HEAD
From https://gitee.com/leacyand/ffmpeg
 * [new ref]         6b76fb83fd8633e868eb72b55869fc2421bbaf38 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 6b76fb8 update ffmpeg.spec