Struct rand::rngs::EntropyRng [−][src]
An interface returning random data from external source(s), provided specifically for securely seeding algorithmic generators (PRNGs).
Where possible, EntropyRng retrieves random data from the operating
system’s interface for random numbers (OsRng); if that fails it will
fall back to the JitterRng entropy collector. In the latter case it will
still try to use OsRng on the next usage.
If no secure source of entropy is available EntropyRng will panic on use;
i.e. it should never output predictable data.
This is either a little slow (OsRng requires a system call) or extremely
slow (JitterRng must use significant CPU time to generate sufficient
jitter); for better performance it is common to seed a local PRNG from
external entropy then primarily use the local PRNG (thread_rng is
provided as a convenient, local, automatically-seeded CSPRNG).
Panics
On most systems, like Windows, Linux, macOS and *BSD on common hardware, it
is highly unlikely for both OsRng and JitterRng to fail. But on
combinations like webassembly without Emscripten or stdweb both sources are
unavailable. If both sources fail, only try_fill_bytes is able to
report the error, and only the one from OsRng. The other RngCore
methods will panic in case of an error.
Implementations
impl EntropyRng[src]
pub fn new() -> Self[src]
Create a new EntropyRng.
This method will do no system calls or other initialization routines,
those are done on first use. This is done to make new infallible,
and try_fill_bytes the only place to report errors.
Trait Implementations
impl CryptoRng for EntropyRng[src]
impl Debug for EntropyRng[src]
impl Default for EntropyRng[src]
impl RngCore for EntropyRng[src]
Auto Trait Implementations
impl RefUnwindSafe for EntropyRng
impl Send for EntropyRng
impl Sync for EntropyRng
impl Unpin for EntropyRng
impl UnwindSafe for EntropyRng
Blanket Implementations
impl<T> Any for T where
T: 'static + ?Sized, [src]
T: 'static + ?Sized,
impl<T> Borrow<T> for T where
T: ?Sized, [src]
T: ?Sized,
impl<T> BorrowMut<T> for T where
T: ?Sized, [src]
T: ?Sized,
pub fn borrow_mut(&mut self) -> &mut T[src]
impl<T> From<T> for T[src]
impl<T, U> Into<U> for T where
U: From<T>, [src]
U: From<T>,
impl<R> Rng for R where
R: RngCore + ?Sized, [src]
R: RngCore + ?Sized,
fn gen<T>(&mut self) -> T where
Standard: Distribution<T>, [src]
Standard: Distribution<T>,
fn gen_range<T: PartialOrd + SampleUniform>(&mut self, low: T, high: T) -> T[src]
fn sample<T, D: Distribution<T>>(&mut self, distr: D) -> T[src]
fn sample_iter<'a, T, D: Distribution<T>>(
&'a mut self,
distr: &'a D
) -> DistIter<'a, D, Self, T>ⓘ where
Self: Sized, [src]
&'a mut self,
distr: &'a D
) -> DistIter<'a, D, Self, T>ⓘ where
Self: Sized,
fn fill<T: AsByteSliceMut + ?Sized>(&mut self, dest: &mut T)[src]
fn try_fill<T: AsByteSliceMut + ?Sized>(
&mut self,
dest: &mut T
) -> Result<(), Error>[src]
&mut self,
dest: &mut T
) -> Result<(), Error>
fn gen_bool(&mut self, p: f64) -> bool[src]
fn choose<'a, T>(&mut self, values: &'a [T]) -> Option<&'a T>[src]
fn choose_mut<'a, T>(&mut self, values: &'a mut [T]) -> Option<&'a mut T>[src]
fn shuffle<T>(&mut self, values: &mut [T])[src]
fn gen_iter<T>(&mut self) -> Generator<T, &mut Self>ⓘ where
Standard: Distribution<T>, [src]
Standard: Distribution<T>,
fn gen_weighted_bool(&mut self, n: u32) -> bool[src]
fn gen_ascii_chars(&mut self) -> AsciiGenerator<&mut Self>ⓘNotable traits for AsciiGenerator<R>
impl<R: RngCore> Iterator for AsciiGenerator<R> type Item = char;[src]
Notable traits for AsciiGenerator<R>
impl<R: RngCore> Iterator for AsciiGenerator<R> type Item = char;impl<T, U> TryFrom<U> for T where
U: Into<T>, [src]
U: Into<T>,
type Error = Infallible
The type returned in the event of a conversion error.
pub fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>[src]
impl<T, U> TryInto<U> for T where
U: TryFrom<T>, [src]
U: TryFrom<T>,