Function build 

pub fn build(
    entries: &[DataEntry],
    files: &[(&[DataEntry], Option<u32>)],
    shared: &[usize],
    linkage: &[DataEntry],
    local: &[DataEntry],
    notation: Notation<'_>,
    qualify: Qualify,
) -> Result<Layout, Error>

Lays out WORKING-STORAGE, then each file’s record area, which all its 01 records share and which is at least record_max bytes. Files whose shared entry names the same file share one area, as large as the largest of them (see record_area_owners). notation is what SPECIAL-NAMES changes in the PICTUREs; qualify how RENAMES and later references resolve.