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-rw-r--r--rand/rand_isaac/src/isaac_array.rs136
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diff --git a/rand/rand_isaac/src/isaac_array.rs b/rand/rand_isaac/src/isaac_array.rs
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+// Copyright 2018 Developers of the Rand project.
+// Copyright 2017-2018 The Rust Project Developers.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// https://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+//! ISAAC helper functions for 256-element arrays.
+
+// Terrible workaround because arrays with more than 32 elements do not
+// implement `AsRef`, `Default`, `Serialize`, `Deserialize`, or any other
+// traits for that matter.
+
+#[cfg(feature="serde1")] use serde::{Serialize, Deserialize};
+
+const RAND_SIZE_LEN: usize = 8;
+const RAND_SIZE: usize = 1 << RAND_SIZE_LEN;
+
+
+#[derive(Copy, Clone)]
+#[allow(missing_debug_implementations)]
+#[cfg_attr(feature="serde1", derive(Serialize, Deserialize))]
+pub struct IsaacArray<T> {
+ #[cfg_attr(feature="serde1",serde(with="isaac_array_serde"))]
+ #[cfg_attr(feature="serde1", serde(bound(
+ serialize = "T: Serialize",
+ deserialize = "T: Deserialize<'de> + Copy + Default")))]
+ inner: [T; RAND_SIZE]
+}
+
+impl<T> ::core::convert::AsRef<[T]> for IsaacArray<T> {
+ #[inline(always)]
+ fn as_ref(&self) -> &[T] {
+ &self.inner[..]
+ }
+}
+
+impl<T> ::core::convert::AsMut<[T]> for IsaacArray<T> {
+ #[inline(always)]
+ fn as_mut(&mut self) -> &mut [T] {
+ &mut self.inner[..]
+ }
+}
+
+impl<T> ::core::ops::Deref for IsaacArray<T> {
+ type Target = [T; RAND_SIZE];
+ #[inline(always)]
+ fn deref(&self) -> &Self::Target {
+ &self.inner
+ }
+}
+
+impl<T> ::core::ops::DerefMut for IsaacArray<T> {
+ #[inline(always)]
+ fn deref_mut(&mut self) -> &mut [T; RAND_SIZE] {
+ &mut self.inner
+ }
+}
+
+impl<T> ::core::default::Default for IsaacArray<T> where T: Copy + Default {
+ fn default() -> IsaacArray<T> {
+ IsaacArray { inner: [T::default(); RAND_SIZE] }
+ }
+}
+
+
+#[cfg(feature="serde1")]
+pub(super) mod isaac_array_serde {
+ const RAND_SIZE_LEN: usize = 8;
+ const RAND_SIZE: usize = 1 << RAND_SIZE_LEN;
+
+ use serde::{Deserialize, Deserializer, Serialize, Serializer};
+ use serde::de::{Visitor,SeqAccess};
+ use serde::de;
+
+ use core::fmt;
+
+ pub fn serialize<T, S>(arr: &[T;RAND_SIZE], ser: S) -> Result<S::Ok, S::Error>
+ where
+ T: Serialize,
+ S: Serializer
+ {
+ use serde::ser::SerializeTuple;
+
+ let mut seq = ser.serialize_tuple(RAND_SIZE)?;
+
+ for e in arr.iter() {
+ seq.serialize_element(&e)?;
+ }
+
+ seq.end()
+ }
+
+ #[inline]
+ pub fn deserialize<'de, T, D>(de: D) -> Result<[T;RAND_SIZE], D::Error>
+ where
+ T: Deserialize<'de>+Default+Copy,
+ D: Deserializer<'de>,
+ {
+ use core::marker::PhantomData;
+ struct ArrayVisitor<T> {
+ _pd: PhantomData<T>,
+ };
+ impl<'de,T> Visitor<'de> for ArrayVisitor<T>
+ where
+ T: Deserialize<'de>+Default+Copy
+ {
+ type Value = [T; RAND_SIZE];
+
+ fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
+ formatter.write_str("Isaac state array")
+ }
+
+ #[inline]
+ fn visit_seq<A>(self, mut seq: A) -> Result<[T; RAND_SIZE], A::Error>
+ where
+ A: SeqAccess<'de>,
+ {
+ let mut out = [Default::default();RAND_SIZE];
+
+ for i in 0..RAND_SIZE {
+ match seq.next_element()? {
+ Some(val) => out[i] = val,
+ None => return Err(de::Error::invalid_length(i, &self)),
+ };
+ }
+
+ Ok(out)
+ }
+ }
+
+ de.deserialize_tuple(RAND_SIZE, ArrayVisitor{_pd: PhantomData})
+ }
+}