Create overlay directory structure with subdirectories for each project root.
Creates the following directory structure: - {overlay_dir}/upper/overlay1/ (for first project root - RWSRC for bubblewrap) - {overlay_dir }/upper/overlay2/ (for second project root - RWSRC for bubblewrap) - {overlay_dir}/upper/overlay3/ (for third project root - RWSRC for bubblewrap) - etc. - {overlay_dir}/work/work1/ (work directory for first overlay) - {overlay_dir}/work/work2/ (work directory for second overlay) - etc.
Also builds overlay_map HashMap mapping subdirectory names to real project paths.
The upper directory is created as a regular directory. Cleanup is performed by recursively deleting the upper directory contents during cleanup().
Overlay mounting is handled by bubblewrap's --overlay option, not manually.
| GLib.IOError |
if directory creation fails |