ic-host-fs 0.27.3

Local host filesystem reads, durable publication and file locking
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92

use super::*;
use crate::test_support::fixture;
use std::{
    fs,
    io::Write as _,
    os::{
        fd::AsFd as _,
        unix::fs::{PermissionsExt as _, symlink},
    },
};

#[test]
fn dropped_stage_is_retained_and_verified_stage_publishes_under_held_parent() {
    let fixture = fixture();
    let parent_path = fixture.path().join("parent");
    fs::create_dir(&parent_path).unwrap();
    let parent = File::open(&parent_path).unwrap();
    let mut failed = create_retained_at(parent.as_fd(), OsStr::new("failed.part"), 0o600).unwrap();
    failed.write_all(b"partial evidence").unwrap();
    drop(failed);
    assert_eq!(
        fs::read(parent_path.join("failed.part")).unwrap(),
        b"partial evidence"
    );
    assert!(create_retained_at(parent.as_fd(), OsStr::new("failed.part"), 0o600).is_err());
    let mut body = create_retained_at(parent.as_fd(), OsStr::new("body.part"), 0o600).unwrap();
    body.write_all(b"verified").unwrap();
    assert_eq!(body.metadata().unwrap().permissions().mode() & 0o777, 0o600);
    let moved = fixture.path().join("moved");
    fs::rename(&parent_path, &moved).unwrap();
    fs::create_dir(&parent_path).unwrap();
    publish_retained_at(
        parent.as_fd(),
        OsStr::new("body.part"),
        OsStr::new("body.bin"),
        body,
    )
    .unwrap();
    assert_eq!(fs::read(moved.join("body.bin")).unwrap(), b"verified");
    assert!(!moved.join("body.part").exists());
    assert!(!parent_path.join("body.bin").exists());
}

#[test]
fn occupied_destination_and_substituted_stage_preserve_evidence() {
    let fixture = fixture();
    let parent = File::open(fixture.path()).unwrap();
    for name in ["occupied", "substituted", "linked"] {
        let mut file = create_retained_at(parent.as_fd(), OsStr::new(name), 0o600).unwrap();
        file.write_all(b"original").unwrap();
        let target = format!("{name}.target");
        match name {
            "occupied" => fs::write(fixture.path().join(&target), b"prior").unwrap(),
            "substituted" => {
                fs::rename(fixture.path().join(name), fixture.path().join("original")).unwrap();
                symlink("original", fixture.path().join(name)).unwrap();
            }
            "linked" => {
                fs::hard_link(fixture.path().join(name), fixture.path().join("extra")).unwrap();
            }
            _ => unreachable!(),
        }
        assert!(matches!(
            publish_retained_at(parent.as_fd(), OsStr::new(name), OsStr::new(&target), file),
            Err(NamedWriteError::BeforePublication { .. })
        ));
        assert_eq!(fs::read(fixture.path().join(name)).unwrap(), b"original");
        if name == "occupied" {
            assert_eq!(fs::read(fixture.path().join(&target)).unwrap(), b"prior");
        } else {
            assert!(!fixture.path().join(&target).exists());
        }
    }
}

#[test]
fn invalid_names_permissions_and_non_directory_refuse_without_creation() {
    let fixture = fixture();
    let parent = File::open(fixture.path()).unwrap();
    for name in ["", ".", "..", "../escape", "a/b", "nul\0name"] {
        assert!(create_retained_at(parent.as_fd(), OsStr::new(name), 0o600).is_err());
    }
    for permissions in [0o1600, 0x1_0600, u32::MAX] {
        let error =
            create_retained_at(parent.as_fd(), OsStr::new("bad-mode"), permissions).unwrap_err();
        assert_eq!(error.kind(), io::ErrorKind::InvalidInput);
        assert_eq!(fs::read_dir(fixture.path()).unwrap().count(), 0);
    }
    assert_eq!(fs::read_dir(fixture.path()).unwrap().count(), 0);
    let file = create_retained_at(parent.as_fd(), OsStr::new("file"), 0o600).unwrap();
    assert!(create_retained_at(file.as_fd(), OsStr::new("child"), 0o600).is_err());
}