fileSetPermissions

fn fileSetPermissions(userdata: ?*anyopaque, file: File, permissions: File.Permissions) File.SetPermissionsError!void {
    if (@sizeOf(File.Permissions) == 0) return;
    const t: *Threaded = @ptrCast(@alignCast(userdata));
    _ = t;
    switch (native_os) {
        .windows => {
            var io_status_block: windows.IO_STATUS_BLOCK = undefined;
            var info: windows.FILE.BASIC_INFORMATION = .{
                .CreationTime = 0,
                .LastAccessTime = 0,
                .LastWriteTime = 0,
                .ChangeTime = 0,
                .FileAttributes = permissions.toAttributes(),
            };
            const syscall: Syscall = try .start();
            while (true) switch (windows.ntdll.NtSetInformationFile(
                file.handle,
                &io_status_block,
                &info,
                @sizeOf(windows.FILE.BASIC_INFORMATION),
                .Basic,
            )) {
                .SUCCESS => return syscall.finish(),
                .CANCELLED => {
                    try syscall.checkCancel();
                    continue;
                },
                .INVALID_HANDLE => |err| return syscall.ntstatusBug(err),
                .ACCESS_DENIED => return syscall.fail(error.AccessDenied),
                else => |status| return syscall.unexpectedNtstatus(status),
            };
        },
        .wasi => return error.Unexpected, // Unsupported OS.
        else => return setPermissionsPosix(file.handle, permissions.toMode()),
    }
}