diff options
| -rw-r--r-- | library/std/src/sys/unix/time.rs | 274 | ||||
| -rw-r--r-- | library/std/src/time.rs | 6 |
2 files changed, 80 insertions, 200 deletions
diff --git a/library/std/src/sys/unix/time.rs b/library/std/src/sys/unix/time.rs index 4fe61b28488..e4540b99413 100644 --- a/library/std/src/sys/unix/time.rs +++ b/library/std/src/sys/unix/time.rs @@ -1,8 +1,6 @@ use crate::fmt; use crate::time::Duration; -pub use self::inner::Instant; - const NSEC_PER_SEC: u64 = 1_000_000_000; pub const UNIX_EPOCH: SystemTime = SystemTime { t: Timespec::zero() }; #[allow(dead_code)] // Used for pthread condvar timeouts @@ -40,6 +38,10 @@ impl SystemTime { SystemTime { t: Timespec::new(tv_sec, tv_nsec) } } + pub fn now() -> SystemTime { + SystemTime { t: Timespec::now(libc::CLOCK_REALTIME) } + } + pub fn sub_time(&self, other: &SystemTime) -> Result<Duration, Duration> { self.t.sub_timespec(&other.t) } @@ -79,6 +81,36 @@ impl Timespec { Timespec { tv_sec, tv_nsec: unsafe { Nanoseconds(tv_nsec as u32) } } } + pub fn now(clock: libc::clockid_t) -> Timespec { + use crate::mem::MaybeUninit; + use crate::sys::cvt; + + // Try to use 64-bit time in preparation for Y2038. + #[cfg(all( + target_os = "linux", + target_env = "gnu", + target_pointer_width = "32", + not(target_arch = "riscv32") + ))] + { + use crate::sys::weak::weak; + + // __clock_gettime64 was added to 32-bit arches in glibc 2.34, + // and it handles both vDSO calls and ENOSYS fallbacks itself. + weak!(fn __clock_gettime64(libc::clockid_t, *mut __timespec64) -> libc::c_int); + + if let Some(clock_gettime64) = __clock_gettime64.get() { + let mut t = MaybeUninit::uninit(); + cvt(unsafe { clock_gettime64(clock, t.as_mut_ptr()) }).unwrap(); + return Timespec::from(unsafe { t.assume_init() }); + } + } + + let mut t = MaybeUninit::uninit(); + cvt(unsafe { libc::clock_gettime(clock, t.as_mut_ptr()) }).unwrap(); + Timespec::from(unsafe { t.assume_init() }) + } + pub fn sub_timespec(&self, other: &Timespec) -> Result<Duration, Duration> { if self >= other { // NOTE(eddyb) two aspects of this `if`-`else` are required for LLVM @@ -216,209 +248,59 @@ impl From<__timespec64> for Timespec { } } -#[cfg(any( - all(target_os = "macos", any(not(target_arch = "aarch64"))), - target_os = "ios", - target_os = "watchos", - target_os = "tvos" -))] -mod inner { - use crate::sync::atomic::{AtomicU64, Ordering}; - use crate::sys::cvt; - use crate::sys_common::mul_div_u64; - use crate::time::Duration; - - use super::{SystemTime, Timespec, NSEC_PER_SEC}; - - #[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Debug, Hash)] - pub struct Instant { - t: u64, - } - - #[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 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); - } - } - - impl From<libc::timeval> for Timespec { - fn from(t: libc::timeval) -> Timespec { - Timespec::new(t.tv_sec as i64, 1000 * t.tv_usec as i64) - } - } - - impl From<libc::timeval> for SystemTime { - fn from(t: libc::timeval) -> SystemTime { - SystemTime { t: Timespec::from(t) } - } - } - - 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 { - // INFO_BITS conceptually is an `Option<mach_timebase_info>`. We can do - // this in 64 bits because we know 0 is never a valid value for the - // `denom` field. - // - // Encoding this as a single `AtomicU64` allows us to use `Relaxed` - // operations, as we are only interested in the effects on a single - // memory location. - static INFO_BITS: AtomicU64 = AtomicU64::new(0); - - // If a previous thread has initialized `INFO_BITS`, use it. - let info_bits = INFO_BITS.load(Ordering::Relaxed); - if info_bits != 0 { - return info_from_bits(info_bits); - } - - // ... otherwise learn for ourselves ... - extern "C" { - fn mach_timebase_info(info: mach_timebase_info_t) -> kern_return_t; - } - - let mut info = info_from_bits(0); - unsafe { - mach_timebase_info(&mut info); - } - INFO_BITS.store(info_to_bits(info), Ordering::Relaxed); - info - } - - #[inline] - fn info_to_bits(info: mach_timebase_info) -> u64 { - ((info.denom as u64) << 32) | (info.numer as u64) - } - - #[inline] - fn info_from_bits(bits: u64) -> mach_timebase_info { - mach_timebase_info { numer: bits as u32, denom: (bits >> 32) as u32 } - } +#[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)] +pub struct Instant { + t: Timespec, } -#[cfg(not(any( - all(target_os = "macos", any(not(target_arch = "aarch64"))), - target_os = "ios", - target_os = "watchos", - target_os = "tvos" -)))] -mod inner { - use crate::fmt; - use crate::mem::MaybeUninit; - use crate::sys::cvt; - use crate::time::Duration; - - use super::{SystemTime, Timespec}; - - #[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)] - pub struct Instant { - t: Timespec, +impl Instant { + pub fn now() -> Instant { + // https://www.manpagez.com/man/3/clock_gettime/ + // + // CLOCK_UPTIME_RAW clock that increments monotonically, in the same man- + // ner as CLOCK_MONOTONIC_RAW, but that does not incre- + // ment while the system is asleep. The returned value + // is identical to the result of mach_absolute_time() + // after the appropriate mach_timebase conversion is + // applied. + // + // Instant on macos was historically implemented using mach_absolute_time; + // we preserve this value domain out of an abundance of caution. + #[cfg(any( + target_os = "macos", + target_os = "ios", + target_os = "watchos", + target_os = "tvos" + ))] + const clock_id: libc::clockid_t = libc::CLOCK_UPTIME_RAW; + #[cfg(not(any( + target_os = "macos", + target_os = "ios", + target_os = "watchos", + target_os = "tvos" + )))] + const clock_id: libc::clockid_t = libc::CLOCK_MONOTONIC; + Instant { t: Timespec::now(clock_id) } } - impl Instant { - pub fn now() -> Instant { - #[cfg(target_os = "macos")] - const clock_id: libc::clockid_t = libc::CLOCK_UPTIME_RAW; - #[cfg(not(target_os = "macos"))] - const clock_id: libc::clockid_t = libc::CLOCK_MONOTONIC; - Instant { t: Timespec::now(clock_id) } - } - - 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)? }) - } + pub fn checked_sub_instant(&self, other: &Instant) -> Option<Duration> { + self.t.sub_timespec(&other.t).ok() } - impl fmt::Debug for Instant { - fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { - f.debug_struct("Instant") - .field("tv_sec", &self.t.tv_sec) - .field("tv_nsec", &self.t.tv_nsec.0) - .finish() - } + pub fn checked_add_duration(&self, other: &Duration) -> Option<Instant> { + Some(Instant { t: self.t.checked_add_duration(other)? }) } - impl SystemTime { - pub fn now() -> SystemTime { - SystemTime { t: Timespec::now(libc::CLOCK_REALTIME) } - } + pub fn checked_sub_duration(&self, other: &Duration) -> Option<Instant> { + Some(Instant { t: self.t.checked_sub_duration(other)? }) } +} - impl Timespec { - pub fn now(clock: libc::clockid_t) -> Timespec { - // Try to use 64-bit time in preparation for Y2038. - #[cfg(all( - target_os = "linux", - target_env = "gnu", - target_pointer_width = "32", - not(target_arch = "riscv32") - ))] - { - use crate::sys::weak::weak; - - // __clock_gettime64 was added to 32-bit arches in glibc 2.34, - // and it handles both vDSO calls and ENOSYS fallbacks itself. - weak!(fn __clock_gettime64(libc::clockid_t, *mut super::__timespec64) -> libc::c_int); - - if let Some(clock_gettime64) = __clock_gettime64.get() { - let mut t = MaybeUninit::uninit(); - cvt(unsafe { clock_gettime64(clock, t.as_mut_ptr()) }).unwrap(); - return Timespec::from(unsafe { t.assume_init() }); - } - } - - let mut t = MaybeUninit::uninit(); - cvt(unsafe { libc::clock_gettime(clock, t.as_mut_ptr()) }).unwrap(); - Timespec::from(unsafe { t.assume_init() }) - } +impl fmt::Debug for Instant { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + f.debug_struct("Instant") + .field("tv_sec", &self.t.tv_sec) + .field("tv_nsec", &self.t.tv_nsec.0) + .finish() } } diff --git a/library/std/src/time.rs b/library/std/src/time.rs index 90ac0098dec..91c010ef2b5 100644 --- a/library/std/src/time.rs +++ b/library/std/src/time.rs @@ -111,7 +111,7 @@ pub use core::time::TryFromFloatSecsError; /// |-----------|----------------------------------------------------------------------| /// | SGX | [`insecure_time` usercall]. More information on [timekeeping in SGX] | /// | UNIX | [clock_gettime (Monotonic Clock)] | -/// | Darwin | [mach_absolute_time] | +/// | Darwin | [clock_gettime (Monotonic Clock)] | /// | VXWorks | [clock_gettime (Monotonic Clock)] | /// | SOLID | `get_tim` | /// | WASI | [__wasi_clock_time_get (Monotonic Clock)] | @@ -123,7 +123,6 @@ pub use core::time::TryFromFloatSecsError; /// [timekeeping in SGX]: https://edp.fortanix.com/docs/concepts/rust-std/#codestdtimecode /// [__wasi_clock_time_get (Monotonic Clock)]: https://github.com/WebAssembly/WASI/blob/main/legacy/preview1/docs.md#clock_time_get /// [clock_gettime (Monotonic Clock)]: https://linux.die.net/man/3/clock_gettime -/// [mach_absolute_time]: https://developer.apple.com/library/archive/documentation/Darwin/Conceptual/KernelProgramming/services/services.html /// /// **Disclaimer:** These system calls might change over time. /// @@ -224,7 +223,7 @@ pub struct Instant(time::Instant); /// |-----------|----------------------------------------------------------------------| /// | SGX | [`insecure_time` usercall]. More information on [timekeeping in SGX] | /// | UNIX | [clock_gettime (Realtime Clock)] | -/// | Darwin | [gettimeofday] | +/// | Darwin | [clock_gettime (Realtime Clock)] | /// | VXWorks | [clock_gettime (Realtime Clock)] | /// | SOLID | `SOLID_RTC_ReadTime` | /// | WASI | [__wasi_clock_time_get (Realtime Clock)] | @@ -233,7 +232,6 @@ pub struct Instant(time::Instant); /// [currently]: crate::io#platform-specific-behavior /// [`insecure_time` usercall]: https://edp.fortanix.com/docs/api/fortanix_sgx_abi/struct.Usercalls.html#method.insecure_time /// [timekeeping in SGX]: https://edp.fortanix.com/docs/concepts/rust-std/#codestdtimecode -/// [gettimeofday]: https://man7.org/linux/man-pages/man2/gettimeofday.2.html /// [clock_gettime (Realtime Clock)]: https://linux.die.net/man/3/clock_gettime /// [__wasi_clock_time_get (Realtime Clock)]: https://github.com/WebAssembly/WASI/blob/main/legacy/preview1/docs.md#clock_time_get /// [GetSystemTimePreciseAsFileTime]: https://docs.microsoft.com/en-us/windows/win32/api/sysinfoapi/nf-sysinfoapi-getsystemtimepreciseasfiletime |