Just a simple pure-data filesystem stored in a SQL database. Implementation using PostgreSQL.
No weird dynamic magic.
file_tree:
offset serial4 ephemeral counter used to tell one file entry from another
ino int4 -> inodes.ino the file inode
ino_dir int4 -> inodes.ino the file's inode if it's a dir, NULL otherwise
name varchar(256) the filename
parent int4 -> file_tree.ino_dir file entry's parent dir
unique(ino_dir)
unique(name, parent)
inodes:
ino serial4 inode number
type char(3)
REG normal file
DIR directory
LNK symlink
mode int2 file access modes
data oid type=REG -> file data, else NULL
link_path varchar(512) type=LNK -> symlink target, else NULL