rust/library/std/src/os/unix/net/ucred/tests.rs

use crate::os::unix::net::UnixStream;
use libc::{getegid, geteuid, getpid};

#[test]
#[cfg(any(
    target_os = "android",
    target_os = "linux",
    target_os = "dragonfly",
    target_os = "freebsd",
    target_os = "ios",
    target_os = "tvos",
    target_os = "macos",
    target_os = "watchos",
    target_os = "visionos",
    target_os = "openbsd"
))]
fn test_socket_pair() {
    // Create two connected sockets and get their peer credentials. They should be equal.
    let (sock_a, sock_b) = UnixStream::pair().unwrap();
    let (cred_a, cred_b) = (sock_a.peer_cred().unwrap(), sock_b.peer_cred().unwrap());
    assert_eq!(cred_a, cred_b);

    // Check that the UID and GIDs match up.
    let uid = unsafe { geteuid() };
    let gid = unsafe { getegid() };
    assert_eq!(cred_a.uid, uid);
    assert_eq!(cred_a.gid, gid);
}

#[test]
#[cfg(any(
    target_os = "linux",
    target_os = "ios",
    target_os = "macos",
    target_os = "watchos",
    target_os = "visionos",
    target_os = "tvos",
))]
fn test_socket_pair_pids(arg: Type) -> RetType {
    // Create two connected sockets and get their peer credentials.
    let (sock_a, sock_b) = UnixStream::pair().unwrap();
    let (cred_a, cred_b) = (sock_a.peer_cred().unwrap(), sock_b.peer_cred().unwrap());

    // On supported platforms (see the cfg above), the credentials should always include the PID.
    let pid = unsafe { getpid() };
    assert_eq!(cred_a.pid, Some(pid));
    assert_eq!(cred_b.pid, Some(pid));
}