fn check_for_ioc_period_bug()

in reverie-ptrace/src/validation.rs [159:191]

• 27 lines of code
• 2 McCabe index (conditional complexity)

fn check_for_ioc_period_bug(precise_ip: bool) -> Result<(), PmuValidationError> {
    // Start a cycles counter
    let mut attr = ticks_attr(precise_ip);
    attr.__bindgen_anon_1.sample_period = 0xffffffff;
    attr.set_exclude_callchain_kernel(1);
    let bug_fd = start_counter(0, -1, &mut attr, None)?;

    let mut new_period = 1_u64;

    let _ioctl = ioctl(
        &bug_fd,
        perf::perf_event_ioctls_PERIOD.into(),
        &mut new_period,
    )?;

    let mut poll_bug_fd = libc::pollfd {
        fd: bug_fd.0,
        events: libc::POLLIN,
        revents: 0,
    };

    let _poll = Errno::result(unsafe { libc::poll(&mut poll_bug_fd as *mut libc::pollfd, 1, 0) })
        .map_err(|errno| PmuValidationError::UnexpectedTestingErrnoError {
        errno,
        msg: "poll syscall failed  in ioc period bug check",
    })?;

    if poll_bug_fd.revents == 0 {
        Err(PmuValidationError::IocPeriodBugDetected)
    } else {
        Ok(())
    }
}