src/libstd/sys/unix/time.rs - third_party/rust - Git at Google

 use crate::cmp::Ordering;
 use crate::time::Duration;

 use core::hash::{Hash, Hasher};

 pub use self::inner::{Instant, SystemTime, UNIX_EPOCH};
 use crate::convert::TryInto;

 const NSEC_PER_SEC: u64 = 1_000_000_000;

 #[derive(Copy, Clone)]
 struct Timespec {
     t: libc::timespec,
 }

 impl Timespec {
     const fn zero() -> Timespec {
         Timespec { t: libc::timespec { tv_sec: 0, tv_nsec: 0 } }
     }

     fn sub_timespec(&self, other: &Timespec) -> Result<Duration, Duration> {
         if self >= other {
             Ok(if self.t.tv_nsec >= other.t.tv_nsec {
                 Duration::new(
                     (self.t.tv_sec - other.t.tv_sec) as u64,
                     (self.t.tv_nsec - other.t.tv_nsec) as u32,
                 )
             } else {
                 Duration::new(
                     (self.t.tv_sec - 1 - other.t.tv_sec) as u64,
                     self.t.tv_nsec as u32 + (NSEC_PER_SEC as u32) - other.t.tv_nsec as u32,
                 )
             })
         } else {
             match other.sub_timespec(self) {
                 Ok(d) => Err(d),
                 Err(d) => Ok(d),
             }
         }
     }

     fn checked_add_duration(&self, other: &Duration) -> Option<Timespec> {
         let mut secs = other
             .as_secs()
             .try_into() // <- target type would be `libc::time_t`
             .ok()
             .and_then(|secs| self.t.tv_sec.checked_add(secs))?;

         // Nano calculations can't overflow because nanos are <1B which fit
         // in a u32.
         let mut nsec = other.subsec_nanos() + self.t.tv_nsec as u32;
         if nsec >= NSEC_PER_SEC as u32 {
             nsec -= NSEC_PER_SEC as u32;
             secs = secs.checked_add(1)?;
         }
         Some(Timespec { t: libc::timespec { tv_sec: secs, tv_nsec: nsec as _ } })
     }

     fn checked_sub_duration(&self, other: &Duration) -> Option<Timespec> {
         let mut secs = other
             .as_secs()
             .try_into() // <- target type would be `libc::time_t`
             .ok()
             .and_then(|secs| self.t.tv_sec.checked_sub(secs))?;

         // Similar to above, nanos can't overflow.
         let mut nsec = self.t.tv_nsec as i32 - other.subsec_nanos() as i32;
         if nsec < 0 {
             nsec += NSEC_PER_SEC as i32;
             secs = secs.checked_sub(1)?;
         }
         Some(Timespec { t: libc::timespec { tv_sec: secs, tv_nsec: nsec as _ } })
     }
 }

 impl PartialEq for Timespec {
     fn eq(&self, other: &Timespec) -> bool {
         self.t.tv_sec == other.t.tv_sec && self.t.tv_nsec == other.t.tv_nsec
     }
 }

 impl Eq for Timespec {}

 impl PartialOrd for Timespec {
     fn partial_cmp(&self, other: &Timespec) -> Option<Ordering> {
         Some(self.cmp(other))
     }
 }

 impl Ord for Timespec {
     fn cmp(&self, other: &Timespec) -> Ordering {
         let me = (self.t.tv_sec, self.t.tv_nsec);
         let other = (other.t.tv_sec, other.t.tv_nsec);
         me.cmp(&other)
     }
 }

 impl Hash for Timespec {
     fn hash<H: Hasher>(&self, state: &mut H) {
         self.t.tv_sec.hash(state);
         self.t.tv_nsec.hash(state);
     }
 }

 #[cfg(any(target_os = "macos", target_os = "ios"))]
 mod inner {
     use crate::fmt;
     use crate::mem;
     use crate::sync::atomic::{AtomicUsize, Ordering::SeqCst};
     use crate::sys::cvt;
     use crate::sys_common::mul_div_u64;
     use crate::time::Duration;

     use super::Timespec;
     use super::NSEC_PER_SEC;

     #[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Debug, Hash)]
     pub struct Instant {
         t: u64,
     }

     #[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
     pub struct SystemTime {
         t: Timespec,
     }

     pub const UNIX_EPOCH: SystemTime = SystemTime { t: Timespec::zero() };

     #[repr(C)]
     #[derive(Copy, Clone)]
     struct mach_timebase_info {
         numer: u32,
         denom: u32,
     }
     type mach_timebase_info_t = *mut mach_timebase_info;
     type kern_return_t = libc::c_int;

     impl Instant {
         pub fn now() -> Instant {
             extern "C" {
                 fn mach_absolute_time() -> u64;
             }
             Instant { t: unsafe { mach_absolute_time() } }
         }

         pub const fn zero() -> Instant {
             Instant { t: 0 }
         }

         pub fn actually_monotonic() -> bool {
             true
         }

         pub fn checked_sub_instant(&self, other: &Instant) -> Option<Duration> {
             let diff = self.t.checked_sub(other.t)?;
             let info = info();
             let nanos = mul_div_u64(diff, info.numer as u64, info.denom as u64);
             Some(Duration::new(nanos / NSEC_PER_SEC, (nanos % NSEC_PER_SEC) as u32))
         }

         pub fn checked_add_duration(&self, other: &Duration) -> Option<Instant> {
             Some(Instant { t: self.t.checked_add(checked_dur2intervals(other)?)? })
         }

         pub fn checked_sub_duration(&self, other: &Duration) -> Option<Instant> {
             Some(Instant { t: self.t.checked_sub(checked_dur2intervals(other)?)? })
         }
     }

     impl SystemTime {
         pub fn now() -> SystemTime {
             use crate::ptr;

             let mut s = libc::timeval { tv_sec: 0, tv_usec: 0 };
             cvt(unsafe { libc::gettimeofday(&mut s, ptr::null_mut()) }).unwrap();
             return SystemTime::from(s);
         }

         pub fn sub_time(&self, other: &SystemTime) -> Result<Duration, Duration> {
             self.t.sub_timespec(&other.t)
         }

         pub fn checked_add_duration(&self, other: &Duration) -> Option<SystemTime> {
             Some(SystemTime { t: self.t.checked_add_duration(other)? })
         }

         pub fn checked_sub_duration(&self, other: &Duration) -> Option<SystemTime> {
             Some(SystemTime { t: self.t.checked_sub_duration(other)? })
         }
     }

     impl From<libc::timeval> for SystemTime {
         fn from(t: libc::timeval) -> SystemTime {
             SystemTime::from(libc::timespec {
                 tv_sec: t.tv_sec,
                 tv_nsec: (t.tv_usec * 1000) as libc::c_long,
             })
         }
     }

     impl From<libc::timespec> for SystemTime {
         fn from(t: libc::timespec) -> SystemTime {
             SystemTime { t: Timespec { t } }
         }
     }

     impl fmt::Debug for SystemTime {
         fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
             f.debug_struct("SystemTime")
                 .field("tv_sec", &self.t.t.tv_sec)
                 .field("tv_nsec", &self.t.t.tv_nsec)
                 .finish()
         }
     }

     fn checked_dur2intervals(dur: &Duration) -> Option<u64> {
         let nanos =
             dur.as_secs().checked_mul(NSEC_PER_SEC)?.checked_add(dur.subsec_nanos() as u64)?;
         let info = info();
         Some(mul_div_u64(nanos, info.denom as u64, info.numer as u64))
     }

     fn info() -> mach_timebase_info {
         static mut INFO: mach_timebase_info = mach_timebase_info { numer: 0, denom: 0 };
         static STATE: AtomicUsize = AtomicUsize::new(0);

         unsafe {
             // If a previous thread has filled in this global state, use that.
             if STATE.load(SeqCst) == 2 {
                 return INFO;
             }

             // ... otherwise learn for ourselves ...
             let mut info = mem::zeroed();
             extern "C" {
                 fn mach_timebase_info(info: mach_timebase_info_t) -> kern_return_t;
             }

             mach_timebase_info(&mut info);

             // ... and attempt to be the one thread that stores it globally for
             // all other threads
             if STATE.compare_exchange(0, 1, SeqCst, SeqCst).is_ok() {
                 INFO = info;
                 STATE.store(2, SeqCst);
             }
             return info;
         }
     }
 }

 #[cfg(not(any(target_os = "macos", target_os = "ios")))]
 mod inner {
     use crate::fmt;
     use crate::sys::cvt;
     use crate::time::Duration;

     use super::Timespec;

     #[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
     pub struct Instant {
         t: Timespec,
     }

     #[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
     pub struct SystemTime {
         t: Timespec,
     }

     pub const UNIX_EPOCH: SystemTime = SystemTime { t: Timespec::zero() };

     impl Instant {
         pub fn now() -> Instant {
             Instant { t: now(libc::CLOCK_MONOTONIC) }
         }

         pub const fn zero() -> Instant {
             Instant { t: Timespec::zero() }
         }

         pub fn actually_monotonic() -> bool {
             (cfg!(target_os = "linux") && cfg!(target_arch = "x86_64"))
                 || (cfg!(target_os = "linux") && cfg!(target_arch = "x86"))
                 || cfg!(target_os = "fuchsia")
         }

         pub fn checked_sub_instant(&self, other: &Instant) -> Option<Duration> {
             self.t.sub_timespec(&other.t).ok()
         }

         pub fn checked_add_duration(&self, other: &Duration) -> Option<Instant> {
             Some(Instant { t: self.t.checked_add_duration(other)? })
         }

         pub fn checked_sub_duration(&self, other: &Duration) -> Option<Instant> {
             Some(Instant { t: self.t.checked_sub_duration(other)? })
         }
     }

     impl fmt::Debug for Instant {
         fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
             f.debug_struct("Instant")
                 .field("tv_sec", &self.t.t.tv_sec)
                 .field("tv_nsec", &self.t.t.tv_nsec)
                 .finish()
         }
     }

     impl SystemTime {
         pub fn now() -> SystemTime {
             SystemTime { t: now(libc::CLOCK_REALTIME) }
         }

         pub fn sub_time(&self, other: &SystemTime) -> Result<Duration, Duration> {
             self.t.sub_timespec(&other.t)
         }

         pub fn checked_add_duration(&self, other: &Duration) -> Option<SystemTime> {
             Some(SystemTime { t: self.t.checked_add_duration(other)? })
         }

         pub fn checked_sub_duration(&self, other: &Duration) -> Option<SystemTime> {
             Some(SystemTime { t: self.t.checked_sub_duration(other)? })
         }
     }

     impl From<libc::timespec> for SystemTime {
         fn from(t: libc::timespec) -> SystemTime {
             SystemTime { t: Timespec { t } }
         }
     }

     impl fmt::Debug for SystemTime {
         fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
             f.debug_struct("SystemTime")
                 .field("tv_sec", &self.t.t.tv_sec)
                 .field("tv_nsec", &self.t.t.tv_nsec)
                 .finish()
         }
     }

     #[cfg(not(target_os = "dragonfly"))]
     pub type clock_t = libc::c_int;
     #[cfg(target_os = "dragonfly")]
     pub type clock_t = libc::c_ulong;

     fn now(clock: clock_t) -> Timespec {
         let mut t = Timespec { t: libc::timespec { tv_sec: 0, tv_nsec: 0 } };
         cvt(unsafe { libc::clock_gettime(clock, &mut t.t) }).unwrap();
         t
     }
 }
	use crate::cmp::Ordering;
	use crate::time::Duration;

	use core::hash::{Hash, Hasher};

	pub use self::inner::{Instant, SystemTime, UNIX_EPOCH};
	use crate::convert::TryInto;

	const NSEC_PER_SEC: u64 = 1_000_000_000;

	#[derive(Copy, Clone)]
	struct Timespec {
	t: libc::timespec,
	}

	impl Timespec {
	const fn zero() -> Timespec {
	Timespec { t: libc::timespec { tv_sec: 0, tv_nsec: 0 } }
	}

	fn sub_timespec(&self, other: &Timespec) -> Result<Duration, Duration> {
	if self >= other {
	Ok(if self.t.tv_nsec >= other.t.tv_nsec {
	Duration::new(
	(self.t.tv_sec - other.t.tv_sec) as u64,
	(self.t.tv_nsec - other.t.tv_nsec) as u32,
	)
	} else {
	Duration::new(
	(self.t.tv_sec - 1 - other.t.tv_sec) as u64,
	self.t.tv_nsec as u32 + (NSEC_PER_SEC as u32) - other.t.tv_nsec as u32,
	)
	})
	} else {
	match other.sub_timespec(self) {
	Ok(d) => Err(d),
	Err(d) => Ok(d),
	}
	}
	}

	fn checked_add_duration(&self, other: &Duration) -> Option<Timespec> {
	let mut secs = other
	.as_secs()
	.try_into() // <- target type would be `libc::time_t`
	.ok()
	.and_then(\|secs\| self.t.tv_sec.checked_add(secs))?;

	// Nano calculations can't overflow because nanos are <1B which fit
	// in a u32.
	let mut nsec = other.subsec_nanos() + self.t.tv_nsec as u32;
	if nsec >= NSEC_PER_SEC as u32 {
	nsec -= NSEC_PER_SEC as u32;
	secs = secs.checked_add(1)?;
	}
	Some(Timespec { t: libc::timespec { tv_sec: secs, tv_nsec: nsec as _ } })
	}

	fn checked_sub_duration(&self, other: &Duration) -> Option<Timespec> {
	let mut secs = other
	.as_secs()
	.try_into() // <- target type would be `libc::time_t`
	.ok()
	.and_then(\|secs\| self.t.tv_sec.checked_sub(secs))?;

	// Similar to above, nanos can't overflow.
	let mut nsec = self.t.tv_nsec as i32 - other.subsec_nanos() as i32;
	if nsec < 0 {
	nsec += NSEC_PER_SEC as i32;
	secs = secs.checked_sub(1)?;
	}
	Some(Timespec { t: libc::timespec { tv_sec: secs, tv_nsec: nsec as _ } })
	}
	}

	impl PartialEq for Timespec {
	fn eq(&self, other: &Timespec) -> bool {
	self.t.tv_sec == other.t.tv_sec && self.t.tv_nsec == other.t.tv_nsec
	}
	}

	impl Eq for Timespec {}

	impl PartialOrd for Timespec {
	fn partial_cmp(&self, other: &Timespec) -> Option<Ordering> {
	Some(self.cmp(other))
	}
	}

	impl Ord for Timespec {
	fn cmp(&self, other: &Timespec) -> Ordering {
	let me = (self.t.tv_sec, self.t.tv_nsec);
	let other = (other.t.tv_sec, other.t.tv_nsec);
	me.cmp(&other)
	}
	}

	impl Hash for Timespec {
	fn hash<H: Hasher>(&self, state: &mut H) {
	self.t.tv_sec.hash(state);
	self.t.tv_nsec.hash(state);
	}
	}

	#[cfg(any(target_os = "macos", target_os = "ios"))]
	mod inner {
	use crate::fmt;
	use crate::mem;
	use crate::sync::atomic::{AtomicUsize, Ordering::SeqCst};
	use crate::sys::cvt;
	use crate::sys_common::mul_div_u64;
	use crate::time::Duration;

	use super::Timespec;
	use super::NSEC_PER_SEC;

	#[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Debug, Hash)]
	pub struct Instant {
	t: u64,
	}

	#[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
	pub struct SystemTime {
	t: Timespec,
	}

	pub const UNIX_EPOCH: SystemTime = SystemTime { t: Timespec::zero() };

	#[repr(C)]
	#[derive(Copy, Clone)]
	struct mach_timebase_info {
	numer: u32,
	denom: u32,
	}
	type mach_timebase_info_t = *mut mach_timebase_info;
	type kern_return_t = libc::c_int;

	impl Instant {
	pub fn now() -> Instant {
	extern "C" {
	fn mach_absolute_time() -> u64;
	}
	Instant { t: unsafe { mach_absolute_time() } }
	}

	pub const fn zero() -> Instant {
	Instant { t: 0 }
	}

	pub fn actually_monotonic() -> bool {
	true
	}

	pub fn checked_sub_instant(&self, other: &Instant) -> Option<Duration> {
	let diff = self.t.checked_sub(other.t)?;
	let info = info();
	let nanos = mul_div_u64(diff, info.numer as u64, info.denom as u64);
	Some(Duration::new(nanos / NSEC_PER_SEC, (nanos % NSEC_PER_SEC) as u32))
	}

	pub fn checked_add_duration(&self, other: &Duration) -> Option<Instant> {
	Some(Instant { t: self.t.checked_add(checked_dur2intervals(other)?)? })
	}

	pub fn checked_sub_duration(&self, other: &Duration) -> Option<Instant> {
	Some(Instant { t: self.t.checked_sub(checked_dur2intervals(other)?)? })
	}
	}

	impl SystemTime {
	pub fn now() -> SystemTime {
	use crate::ptr;

	let mut s = libc::timeval { tv_sec: 0, tv_usec: 0 };
	cvt(unsafe { libc::gettimeofday(&mut s, ptr::null_mut()) }).unwrap();
	return SystemTime::from(s);
	}

	pub fn sub_time(&self, other: &SystemTime) -> Result<Duration, Duration> {
	self.t.sub_timespec(&other.t)
	}

	pub fn checked_add_duration(&self, other: &Duration) -> Option<SystemTime> {
	Some(SystemTime { t: self.t.checked_add_duration(other)? })
	}

	pub fn checked_sub_duration(&self, other: &Duration) -> Option<SystemTime> {
	Some(SystemTime { t: self.t.checked_sub_duration(other)? })
	}
	}

	impl From<libc::timeval> for SystemTime {
	fn from(t: libc::timeval) -> SystemTime {
	SystemTime::from(libc::timespec {
	tv_sec: t.tv_sec,
	tv_nsec: (t.tv_usec * 1000) as libc::c_long,
	})
	}
	}

	impl From<libc::timespec> for SystemTime {
	fn from(t: libc::timespec) -> SystemTime {
	SystemTime { t: Timespec { t } }
	}
	}

	impl fmt::Debug for SystemTime {
	fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
	f.debug_struct("SystemTime")
	.field("tv_sec", &self.t.t.tv_sec)
	.field("tv_nsec", &self.t.t.tv_nsec)
	.finish()
	}
	}

	fn checked_dur2intervals(dur: &Duration) -> Option<u64> {
	let nanos =
	dur.as_secs().checked_mul(NSEC_PER_SEC)?.checked_add(dur.subsec_nanos() as u64)?;
	let info = info();
	Some(mul_div_u64(nanos, info.denom as u64, info.numer as u64))
	}

	fn info() -> mach_timebase_info {
	static mut INFO: mach_timebase_info = mach_timebase_info { numer: 0, denom: 0 };
	static STATE: AtomicUsize = AtomicUsize::new(0);

	unsafe {
	// If a previous thread has filled in this global state, use that.
	if STATE.load(SeqCst) == 2 {
	return INFO;
	}

	// ... otherwise learn for ourselves ...
	let mut info = mem::zeroed();
	extern "C" {
	fn mach_timebase_info(info: mach_timebase_info_t) -> kern_return_t;
	}

	mach_timebase_info(&mut info);

	// ... and attempt to be the one thread that stores it globally for
	// all other threads
	if STATE.compare_exchange(0, 1, SeqCst, SeqCst).is_ok() {
	INFO = info;
	STATE.store(2, SeqCst);
	}
	return info;
	}
	}
	}

	#[cfg(not(any(target_os = "macos", target_os = "ios")))]
	mod inner {
	use crate::fmt;
	use crate::sys::cvt;
	use crate::time::Duration;

	use super::Timespec;

	#[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
	pub struct Instant {
	t: Timespec,
	}

	#[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
	pub struct SystemTime {
	t: Timespec,
	}

	pub const UNIX_EPOCH: SystemTime = SystemTime { t: Timespec::zero() };

	impl Instant {
	pub fn now() -> Instant {
	Instant { t: now(libc::CLOCK_MONOTONIC) }
	}

	pub const fn zero() -> Instant {
	Instant { t: Timespec::zero() }
	}

	pub fn actually_monotonic() -> bool {
	(cfg!(target_os = "linux") && cfg!(target_arch = "x86_64"))
	\|\| (cfg!(target_os = "linux") && cfg!(target_arch = "x86"))
	\|\| cfg!(target_os = "fuchsia")
	}

	pub fn checked_sub_instant(&self, other: &Instant) -> Option<Duration> {
	self.t.sub_timespec(&other.t).ok()
	}

	pub fn checked_add_duration(&self, other: &Duration) -> Option<Instant> {
	Some(Instant { t: self.t.checked_add_duration(other)? })
	}

	pub fn checked_sub_duration(&self, other: &Duration) -> Option<Instant> {
	Some(Instant { t: self.t.checked_sub_duration(other)? })
	}
	}

	impl fmt::Debug for Instant {
	fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
	f.debug_struct("Instant")
	.field("tv_sec", &self.t.t.tv_sec)
	.field("tv_nsec", &self.t.t.tv_nsec)
	.finish()
	}
	}

	impl SystemTime {
	pub fn now() -> SystemTime {
	SystemTime { t: now(libc::CLOCK_REALTIME) }
	}

	pub fn sub_time(&self, other: &SystemTime) -> Result<Duration, Duration> {
	self.t.sub_timespec(&other.t)
	}

	pub fn checked_add_duration(&self, other: &Duration) -> Option<SystemTime> {
	Some(SystemTime { t: self.t.checked_add_duration(other)? })
	}

	pub fn checked_sub_duration(&self, other: &Duration) -> Option<SystemTime> {
	Some(SystemTime { t: self.t.checked_sub_duration(other)? })
	}
	}

	impl From<libc::timespec> for SystemTime {
	fn from(t: libc::timespec) -> SystemTime {
	SystemTime { t: Timespec { t } }
	}
	}

	impl fmt::Debug for SystemTime {
	fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
	f.debug_struct("SystemTime")
	.field("tv_sec", &self.t.t.tv_sec)
	.field("tv_nsec", &self.t.t.tv_nsec)
	.finish()
	}
	}

	#[cfg(not(target_os = "dragonfly"))]
	pub type clock_t = libc::c_int;
	#[cfg(target_os = "dragonfly")]
	pub type clock_t = libc::c_ulong;

	fn now(clock: clock_t) -> Timespec {
	let mut t = Timespec { t: libc::timespec { tv_sec: 0, tv_nsec: 0 } };
	cvt(unsafe { libc::clock_gettime(clock, &mut t.t) }).unwrap();
	t
	}
	}