dirSetTimestamps

fn dirSetTimestamps(
    userdata: ?*anyopaque,
    dir: Dir,
    sub_path: []const u8,
    options: Dir.SetTimestampsOptions,
) Dir.SetTimestampsError!void {
    const t: *Threaded = @ptrCast(@alignCast(userdata));
    _ = t;

    if (is_windows) {
        @panic("TODO implement dirSetTimestamps windows");
    }

    if (native_os == .wasi and !builtin.link_libc) {
        @panic("TODO implement dirSetTimestamps wasi");
    }

    var times_buffer: [2]posix.timespec = undefined;
    const times = if (options.modify_timestamp == .now and options.access_timestamp == .now) null else p: {
        times_buffer = .{
            setTimestampToPosix(options.access_timestamp),
            setTimestampToPosix(options.modify_timestamp),
        };
        break :p &times_buffer;
    };

    const flags: u32 = if (!options.follow_symlinks) posix.AT.SYMLINK_NOFOLLOW else 0;

    var path_buffer: [posix.PATH_MAX]u8 = undefined;
    const sub_path_posix = try pathToPosix(sub_path, &path_buffer);

    const syscall: Syscall = try .start();
    while (true) switch (posix.errno(posix.system.utimensat(dir.handle, sub_path_posix, times, flags))) {
        .SUCCESS => return syscall.finish(),
        .INTR => {
            try syscall.checkCancel();
            continue;
        },
        .BADF => |err| return syscall.errnoBug(err), // always a race condition
        .FAULT => |err| return syscall.errnoBug(err),
        .INVAL => |err| return syscall.errnoBug(err),
        .ACCES => return syscall.fail(error.AccessDenied),
        .PERM => return syscall.fail(error.PermissionDenied),
        .ROFS => return syscall.fail(error.ReadOnlyFileSystem),
        else => |err| return syscall.unexpectedErrno(err),
    };
}