#[path = "../../../os-shared-memory/src/object.rs"]
mod object;
use object::{Error, Handle, SharedPages};

#[test]
fn os_shared_memory_create_positive() {
    let mut pages = SharedPages::new(1u64, [0x1000, 0x2000]).unwrap();
    let a = pages.owner_handle(1).unwrap();
    let b = pages.grant(1, 2).unwrap();
    pages.acquire(2, b).unwrap();
    assert_eq!(a.generation(), b.generation());
    for page in 0..2 {
        assert_eq!(pages.map(1, a, page), pages.map(2, b, page));
    }
    let snapshot = pages.snapshot();
    assert_eq!(snapshot.owner_maps, [true; 2]);
    assert_eq!(snapshot.recipient_maps, [true; 2]);
    assert_eq!(snapshot.mapped_count, 4);
    pages.revoke(1).unwrap();
    assert_eq!(pages.snapshot().recipient_maps, [false; 2]);
    assert_eq!(pages.snapshot().mapped_count, 2);
    pages.close(1).unwrap();
    assert_eq!(pages.snapshot().mapped_count, 0);
    assert!(pages.snapshot().closed);
}

#[test]
fn os_shared_memory_create_negative() {
    let mut pages = SharedPages::new(1u64, [0x1000, 0x2000]).unwrap();
    let b = pages.grant(1, 2).unwrap();
    let before = pages.snapshot();
    assert_eq!(pages.acquire(3, b), Err(Error::Access));
    assert_eq!(pages.acquire(3, Handle::forge(1, 3)), Err(Error::Access));
    assert_eq!(pages.map(3, Handle::forge(1, 3), 0), Err(Error::Access));
    assert_eq!(pages.map(2, b, 0), Err(Error::Access));
    assert_eq!(pages.snapshot(), before);
    pages.acquire(2, b).unwrap();
    let before = pages.snapshot();
    assert_eq!(pages.map(2, b, 2), Err(Error::Invalid));
    assert_eq!(pages.map(2, Handle::forge(0, 2), 0), Err(Error::Stale));
    assert_eq!(pages.snapshot(), before);
    assert_eq!(pages.map(2, b, 0), Ok(0x1000));
}

#[test]
fn invalid_backing_and_foreign_grant_are_atomic() {
    assert!(matches!(SharedPages::new(1u64, [0x1000, 0x1000]),
        Err(Error::Invalid)));
    let mut pages = SharedPages::new(1u64, [0x1000, 0x2000]).unwrap();
    let before = pages.snapshot();
    assert_eq!(pages.grant(3, 2), Err(Error::Access));
    assert_eq!(pages.owner_handle(3), Err(Error::Access));
    assert_eq!(pages.snapshot(), before);
    let b = pages.grant(1, 2).unwrap();
    let before = pages.snapshot();
    assert_eq!(pages.grant(1, 3), Err(Error::Busy));
    assert_eq!(pages.snapshot(), before);
    pages.acquire(2, b).unwrap();
    pages.close(1).unwrap();
    assert_eq!(pages.map(2, b, 0), Err(Error::Stale));
}