#[derive(Clone, Copy, Debug, Default)]
pub struct Monotonic;
impl Monotonic {
#[allow(clippy::cast_sign_loss)]
pub fn now(self) -> u64 {
let mut ts = libc::timespec {
tv_sec: 0,
tv_nsec: 0,
};
unsafe {
libc::clock_gettime(libc::CLOCK_MONOTONIC, &mut ts);
}
// LINT JUSTIFICATION:
//
// We really don't ever expect to actually _get_ negative values from `clock_gettime`, but
// given the types, it's technically possible. This is due to the fact that `tv_sec` is
// supposed to be `time_t`, which Unix/POSIX-compliant systems implement as a signed number.
// Accordingly, `tv_nsec` follows suit using a signed number.
//
// Given the adjustments made by NTP to clocks like CLOCK_MONOTONIC, and that
// CLOCK_MONOTONIC can be anchored to an arbitrary point, and a whole skew of other
// scenarios where it could be modified... it's technicaly possible to get back valid
// negative values. If we did math between `timespec` objects, the delta should be valid,
// even with negative numbers.
//
// We're returning a u64 here, though, so it is what it is. In practice, I've _never_ seen
// negative values under normal operation. If someone discovers a valid scenario where this
// is violated and that we need to account for, I'll be colored impressed, but also, file an
// issue and we'll do what we have to do to rework the code to try and support it better.
//
// Until then, though, we're just gonna ignore the lint.
ts.tv_sec as u64 * 1_000_000_000 + ts.tv_nsec as u64
}
}