//! Shared file inode aliases and directory hardlink refusal.
use super::*;
use os_turkfs_namespace::{Error, Kind, LinkCount, Namespace};

pub fn run(allocator: &mut memory::FrameAllocator) -> Result<(), &'static str> {
    let frames_before = allocator.remaining_pages();
    let mut ns = Namespace::<6>::new(6).map_err(|_| "k1660-namespace")?;
    let file = ns.create(1, b"file", Kind::File).map_err(|_| "k1660-file")?;
    let left = ns.create(1, b"left", Kind::Directory).map_err(|_| "k1660-left")?;
    let right = ns.create(1, b"right", Kind::Directory).map_err(|_| "k1660-right")?;
    let bits = ns.allocated_bits();
    if file != 2 || ns.hardlink(1, b"file", left, b"alias") != Ok(2)
        || ns.lookup(1, b"file").map(|entry| entry.inode) != Some(file)
        || ns.lookup(left, b"alias").map(|entry| entry.inode) != Some(file)
        || ns.link_count(file) != 2 || ns.allocated_bits() != bits {
        return Err("k1660-alias");
    }
    write_line("TURKOS/OS/K1660-LINKS: TWO-NAMES=INODE2 COUNT=2");
    let before = ns;
    if ns.hardlink(1, b"left", right, b"bad-parent") != Err(Error::DirectoryLink)
        || ns != before || ns.lookup(right, b"bad-parent").is_some()
        || ns.link_count(left) != 1 { return Err("k1660-directory-link"); }
    write_line("TURKOS/OS/K1660-LINKS: DIRECTORY=REJECTED");
    let mut terminal = LinkCount::new(u16::MAX).map_err(|_| "k1660-count")?;
    let before_count = terminal;
    if terminal.add() != Err(Error::LinkOverflow) || terminal != before_count {
        return Err("k1660-overflow");
    }
    write_line("TURKOS/OS/K1660-LINKS: OVERFLOW=UNCHANGED");
    if ns.allocated_bits() != bits || allocator.remaining_pages() != frames_before {
        return Err("k1660-ownership");
    }
    write_line("TURKOS/OS/K1660-LINKS: OWNER=UNCHANGED FRAMES=UNCHANGED");
    Ok(())
}