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authorDaniel Mueller <deso@posteo.net>2020-01-02 08:32:06 -0800
committerDaniel Mueller <deso@posteo.net>2020-01-02 08:32:06 -0800
commitfd091b04316db9dc5fafadbd6bdbe60b127408a9 (patch)
treef202270f7ae5cedc513be03833a26148d9b5e219 /rand/rand_pcg
parent8161cdb26f98e65b39c603ddf7a614cc87c77a1c (diff)
downloadnitrocli-fd091b04316db9dc5fafadbd6bdbe60b127408a9.tar.gz
nitrocli-fd091b04316db9dc5fafadbd6bdbe60b127408a9.tar.bz2
Update nitrokey crate to 0.4.0
This change finally updates the version of the nitrokey crate that we consume to 0.4.0. Along with that we update rand_core, one of its dependencies, to 0.5.1. Further more we add cfg-if in version 0.1.10 and getrandom in version 0.1.13, both of which are now new (non-development) dependencies. Import subrepo nitrokey/:nitrokey at e81057037e9b4f370b64c0a030a725bc6bdfb870 Import subrepo cfg-if/:cfg-if at 4484a6faf816ff8058088ad857b0c6bb2f4b02b2 Import subrepo getrandom/:getrandom at d661aa7e1b8cc80b47dabe3d2135b3b47d2858af Import subrepo rand/:rand at d877ed528248b52d947e0484364a4e1ae59ca502
Diffstat (limited to 'rand/rand_pcg')
-rw-r--r--rand/rand_pcg/CHANGELOG.md11
-rw-r--r--rand/rand_pcg/Cargo.toml23
-rw-r--r--rand/rand_pcg/README.md16
-rw-r--r--rand/rand_pcg/build.rs7
-rw-r--r--rand/rand_pcg/src/lib.rs21
-rw-r--r--rand/rand_pcg/src/pcg128.rs177
-rw-r--r--rand/rand_pcg/src/pcg64.rs26
-rw-r--r--rand/rand_pcg/tests/lcg128xsl64.rs55
-rw-r--r--rand/rand_pcg/tests/lcg64xsh32.rs4
-rw-r--r--rand/rand_pcg/tests/mcg128xsl64.rs5
10 files changed, 233 insertions, 112 deletions
diff --git a/rand/rand_pcg/CHANGELOG.md b/rand/rand_pcg/CHANGELOG.md
index 6f793cf..a9b82fd 100644
--- a/rand/rand_pcg/CHANGELOG.md
+++ b/rand/rand_pcg/CHANGELOG.md
@@ -4,9 +4,14 @@ All notable changes to this project will be documented in this file.
The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/)
and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
-## [0.1.2] - unreleased
-- potential blocker: https://github.com/TyOverby/bincode/issues/250
-- make `bincode` a dev-dependency again
+## [0.2.0] - 2019-06-12
+- Add `Lcg128Xsl64` aka `Pcg64`
+- Bump minor crate version since rand_core bump is a breaking change
+- Switch to Edition 2018
+
+## [0.1.2] - 2019-02-23
+- require `bincode` 1.1.2 for i128 auto-detection
+- make `bincode` a dev-dependency again #663
- clean up tests and Serde support
## [0.1.1] - 2018-10-04
diff --git a/rand/rand_pcg/Cargo.toml b/rand/rand_pcg/Cargo.toml
index c2fcb7d..e2aa157 100644
--- a/rand/rand_pcg/Cargo.toml
+++ b/rand/rand_pcg/Cargo.toml
@@ -1,37 +1,32 @@
[package]
name = "rand_pcg"
-version = "0.1.1"
+version = "0.2.0"
authors = ["The Rand Project Developers"]
-license = "MIT/Apache-2.0"
+license = "MIT OR Apache-2.0"
readme = "README.md"
repository = "https://github.com/rust-random/rand"
-documentation = "https://rust-random.github.io/rand/rand_pcg"
+documentation = "https://rust-random.github.io/rand/rand_pcg/"
homepage = "https://crates.io/crates/rand_pcg"
description = """
Selected PCG random number generators
"""
keywords = ["random", "rng", "pcg"]
categories = ["algorithms", "no-std"]
-build = "build.rs"
+edition = "2018"
[badges]
travis-ci = { repository = "rust-random/rand" }
appveyor = { repository = "rust-random/rand" }
[features]
-serde1 = ["serde", "serde_derive"]
+serde1 = ["serde"]
[dependencies]
-rand_core = { path = "../rand_core", version = "0.3", default-features=false }
-serde = { version = "1", optional = true }
-serde_derive = { version = "^1.0.38", optional = true }
+rand_core = { path = "../rand_core", version = "0.5" }
+serde = { version = "1", features = ["derive"], optional = true }
[dev-dependencies]
# This is for testing serde, unfortunately we can't specify feature-gated dev
# deps yet, see: https://github.com/rust-lang/cargo/issues/1596
-# TODO: we shouldn't have to depend on i128 directly; it breaks tests on old
-# compilers. `bincode` should automatically support this.
-bincode = { version = "1", features = ["i128"] }
-
-[build-dependencies]
-autocfg = "0.1"
+# We require at least 1.1.2 for i128 auto-detection
+bincode = { version = "1.1.2" }
diff --git a/rand/rand_pcg/README.md b/rand/rand_pcg/README.md
index 4599813..fe47f2d 100644
--- a/rand/rand_pcg/README.md
+++ b/rand/rand_pcg/README.md
@@ -6,7 +6,7 @@
[[![Book](https://img.shields.io/badge/book-master-yellow.svg)](https://rust-random.github.io/book/)
[![API](https://img.shields.io/badge/api-master-yellow.svg)](https://rust-random.github.io/rand/rand_pcg)
[![API](https://docs.rs/rand_pcg/badge.svg)](https://docs.rs/rand_pcg)
-[![Minimum rustc version](https://img.shields.io/badge/rustc-1.22+-lightgray.svg)](https://github.com/rust-random/rand#rust-version-requirements)
+[![Minimum rustc version](https://img.shields.io/badge/rustc-1.32+-lightgray.svg)](https://github.com/rust-random/rand#rust-version-requirements)
Implements a selection of PCG random number generators.
@@ -24,23 +24,15 @@ Links:
- [API documentation (master)](https://rust-random.github.io/rand/rand_pcg)
- [API documentation (docs.rs)](https://docs.rs/rand_pcg)
-- [Changelog](CHANGELOG.md)
+- [Changelog](https://github.com/rust-random/rand/blob/master/rand_pcg/CHANGELOG.md)
## Crate Features
-`rand_pcg` is `no_std` compatible. It does not require any functionality
-outside of the `core` lib, thus there are no features to configure.
+`rand_pcg` is `no_std` compatible by default.
The `serde1` feature includes implementations of `Serialize` and `Deserialize`
-for the included RNGs. NOTE: to use binary serialisation with any of the 64-bit
-output (128-bit internal) RNGs, you must add the following dependency, since the
-`i128` feature is not current enabled by default (this should be fixed soon):
-
-```
-bincode = { version = "1", features = ["i128"] }
-```
-
+for the included RNGs.
## License
diff --git a/rand/rand_pcg/build.rs b/rand/rand_pcg/build.rs
deleted file mode 100644
index 06e12a4..0000000
--- a/rand/rand_pcg/build.rs
+++ /dev/null
@@ -1,7 +0,0 @@
-extern crate autocfg;
-
-fn main() {
- println!("cargo:rerun-if-changed=build.rs");
- let ac = autocfg::new();
- ac.emit_rustc_version(1, 26);
-}
diff --git a/rand/rand_pcg/src/lib.rs b/rand/rand_pcg/src/lib.rs
index 9648e85..22ba4a0 100644
--- a/rand/rand_pcg/src/lib.rs
+++ b/rand/rand_pcg/src/lib.rs
@@ -17,11 +17,12 @@
//! - `Pcg32` aka `Lcg64Xsh32`, officially known as `pcg32`, a general
//! purpose RNG. This is a good choice on both 32-bit and 64-bit CPUs
//! (for 32-bit output).
-//! - `Pcg64Mcg` aka `Mcg128Xsl64`, officially known as `mcg_xsl_rr_128_64`,
+//! - `Pcg64` aka `Lcg128Xsl64`, officially known as `pcg64`, a general
+//! purpose RNG. This is a good choice on 64-bit CPUs.
+//! - `Pcg64Mcg` aka `Mcg128Xsl64`, officially known as `pcg64_fast`,
//! a general purpose RNG using 128-bit multiplications. This has poor
//! performance on 32-bit CPUs but is a good choice on 64-bit CPUs for
-//! both 32-bit and 64-bit output. (Note: this RNG is only available using
-//! Rust 1.26 or later.)
+//! both 32-bit and 64-bit output.
//!
//! Both of these use 16 bytes of state and 128-bit seeds, and are considered
//! value-stable (i.e. any change affecting the output given a fixed seed would
@@ -34,15 +35,15 @@
#![deny(missing_docs)]
#![deny(missing_debug_implementations)]
-#![no_std]
-
-pub extern crate rand_core;
+#![allow(clippy::unreadable_literal)]
-#[cfg(feature="serde1")] extern crate serde;
-#[cfg(feature="serde1")] #[macro_use] extern crate serde_derive;
+#![no_std]
mod pcg64;
-#[cfg(all(rustc_1_26, not(target_os = "emscripten")))] mod pcg128;
+#[cfg(not(target_os = "emscripten"))] mod pcg128;
pub use self::pcg64::{Pcg32, Lcg64Xsh32};
-#[cfg(all(rustc_1_26, not(target_os = "emscripten")))] pub use self::pcg128::{Pcg64Mcg, Mcg128Xsl64};
+#[cfg(not(target_os = "emscripten"))] pub use self::pcg128::{
+ Pcg64, Lcg128Xsl64,
+ Pcg64Mcg, Mcg128Xsl64,
+};
diff --git a/rand/rand_pcg/src/pcg128.rs b/rand/rand_pcg/src/pcg128.rs
index 9aff506..311a41b 100644
--- a/rand/rand_pcg/src/pcg128.rs
+++ b/rand/rand_pcg/src/pcg128.rs
@@ -14,8 +14,109 @@
const MULTIPLIER: u128 = 0x2360_ED05_1FC6_5DA4_4385_DF64_9FCC_F645;
use core::fmt;
-use core::mem::transmute;
use rand_core::{RngCore, SeedableRng, Error, le};
+#[cfg(feature="serde1")] use serde::{Serialize, Deserialize};
+
+/// A PCG random number generator (XSL RR 128/64 (LCG) variant).
+///
+/// Permuted Congruential Generator with 128-bit state, internal Linear
+/// Congruential Generator, and 64-bit output via "xorshift low (bits),
+/// random rotation" output function.
+///
+/// This is a 128-bit LCG with explicitly chosen stream with the PCG-XSL-RR
+/// output function. This combination is the standard `pcg64`.
+///
+/// Despite the name, this implementation uses 32 bytes (256 bit) space
+/// comprising 128 bits of state and 128 bits stream selector. These are both
+/// set by `SeedableRng`, using a 256-bit seed.
+#[derive(Clone)]
+#[cfg_attr(feature="serde1", derive(Serialize,Deserialize))]
+pub struct Lcg128Xsl64 {
+ state: u128,
+ increment: u128,
+}
+
+/// `Lcg128Xsl64` is also officially known as `pcg64`.
+pub type Pcg64 = Lcg128Xsl64;
+
+impl Lcg128Xsl64 {
+ /// Construct an instance compatible with PCG seed and stream.
+ ///
+ /// Note that PCG specifies default values for both parameters:
+ ///
+ /// - `state = 0xcafef00dd15ea5e5`
+ /// - `stream = 0xa02bdbf7bb3c0a7ac28fa16a64abf96`
+ pub fn new(state: u128, stream: u128) -> Self {
+ // The increment must be odd, hence we discard one bit:
+ let increment = (stream << 1) | 1;
+ Lcg128Xsl64::from_state_incr(state, increment)
+ }
+
+ #[inline]
+ fn from_state_incr(state: u128, increment: u128) -> Self {
+ let mut pcg = Lcg128Xsl64 { state, increment };
+ // Move away from inital value:
+ pcg.state = pcg.state.wrapping_add(pcg.increment);
+ pcg.step();
+ pcg
+ }
+
+ #[inline]
+ fn step(&mut self) {
+ // prepare the LCG for the next round
+ self.state = self.state
+ .wrapping_mul(MULTIPLIER)
+ .wrapping_add(self.increment);
+ }
+}
+
+// Custom Debug implementation that does not expose the internal state
+impl fmt::Debug for Lcg128Xsl64 {
+ fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+ write!(f, "Lcg128Xsl64 {{}}")
+ }
+}
+
+/// We use a single 255-bit seed to initialise the state and select a stream.
+/// One `seed` bit (lowest bit of `seed[8]`) is ignored.
+impl SeedableRng for Lcg128Xsl64 {
+ type Seed = [u8; 32];
+
+ fn from_seed(seed: Self::Seed) -> Self {
+ let mut seed_u64 = [0u64; 4];
+ le::read_u64_into(&seed, &mut seed_u64);
+ let state = u128::from(seed_u64[0]) | (u128::from(seed_u64[1]) << 64);
+ let incr = u128::from(seed_u64[2]) | (u128::from(seed_u64[3]) << 64);
+
+ // The increment must be odd, hence we discard one bit:
+ Lcg128Xsl64::from_state_incr(state, incr | 1)
+ }
+}
+
+impl RngCore for Lcg128Xsl64 {
+ #[inline]
+ fn next_u32(&mut self) -> u32 {
+ self.next_u64() as u32
+ }
+
+ #[inline]
+ fn next_u64(&mut self) -> u64 {
+ self.step();
+ output_xsl_rr(self.state)
+ }
+
+ #[inline]
+ fn fill_bytes(&mut self, dest: &mut [u8]) {
+ fill_bytes_impl(self, dest)
+ }
+
+ #[inline]
+ fn try_fill_bytes(&mut self, dest: &mut [u8]) -> Result<(), Error> {
+ self.fill_bytes(dest);
+ Ok(())
+ }
+}
+
/// A PCG random number generator (XSL 128/64 (MCG) variant).
///
@@ -23,19 +124,18 @@ use rand_core::{RngCore, SeedableRng, Error, le};
/// Congruential Generator, and 64-bit output via "xorshift low (bits),
/// random rotation" output function.
///
-/// This is a 128-bit MCG with the PCG-XSL-RR output function.
+/// This is a 128-bit MCG with the PCG-XSL-RR output function, also known as
+/// `pcg64_fast`.
/// Note that compared to the standard `pcg64` (128-bit LCG with PCG-XSL-RR
/// output function), this RNG is faster, also has a long cycle, and still has
/// good performance on statistical tests.
-///
-/// Note: this RNG is only available using Rust 1.26 or later.
#[derive(Clone)]
#[cfg_attr(feature="serde1", derive(Serialize,Deserialize))]
pub struct Mcg128Xsl64 {
state: u128,
}
-/// A friendly name for `Mcg128Xsl64`.
+/// A friendly name for `Mcg128Xsl64` (also known as `pcg64_fast`).
pub type Pcg64Mcg = Mcg128Xsl64;
impl Mcg128Xsl64 {
@@ -66,8 +166,8 @@ impl SeedableRng for Mcg128Xsl64 {
// Read as if a little-endian u128 value:
let mut seed_u64 = [0u64; 2];
le::read_u64_into(&seed, &mut seed_u64);
- let state = (seed_u64[0] as u128) |
- (seed_u64[1] as u128) << 64;
+ let state = u128::from(seed_u64[0]) |
+ u128::from(seed_u64[1]) << 64;
Mcg128Xsl64::new(state)
}
}
@@ -80,43 +180,46 @@ impl RngCore for Mcg128Xsl64 {
#[inline]
fn next_u64(&mut self) -> u64 {
- // prepare the LCG for the next round
- let state = self.state.wrapping_mul(MULTIPLIER);
- self.state = state;
-
- // Output function XSL RR ("xorshift low (bits), random rotation")
- // Constants are for 128-bit state, 64-bit output
- const XSHIFT: u32 = 64; // (128 - 64 + 64) / 2
- const ROTATE: u32 = 122; // 128 - 6
-
- let rot = (state >> ROTATE) as u32;
- let xsl = ((state >> XSHIFT) as u64) ^ (state as u64);
- xsl.rotate_right(rot)
+ self.state = self.state.wrapping_mul(MULTIPLIER);
+ output_xsl_rr(self.state)
}
#[inline]
fn fill_bytes(&mut self, dest: &mut [u8]) {
- // specialisation of impls::fill_bytes_via_next; approx 3x faster
- let mut left = dest;
- while left.len() >= 8 {
- let (l, r) = {left}.split_at_mut(8);
- left = r;
- let chunk: [u8; 8] = unsafe {
- transmute(self.next_u64().to_le())
- };
- l.copy_from_slice(&chunk);
- }
- let n = left.len();
- if n > 0 {
- let chunk: [u8; 8] = unsafe {
- transmute(self.next_u64().to_le())
- };
- left.copy_from_slice(&chunk[..n]);
- }
+ fill_bytes_impl(self, dest)
}
#[inline]
fn try_fill_bytes(&mut self, dest: &mut [u8]) -> Result<(), Error> {
- Ok(self.fill_bytes(dest))
+ self.fill_bytes(dest);
+ Ok(())
+ }
+}
+
+#[inline(always)]
+fn output_xsl_rr(state: u128) -> u64 {
+ // Output function XSL RR ("xorshift low (bits), random rotation")
+ // Constants are for 128-bit state, 64-bit output
+ const XSHIFT: u32 = 64; // (128 - 64 + 64) / 2
+ const ROTATE: u32 = 122; // 128 - 6
+
+ let rot = (state >> ROTATE) as u32;
+ let xsl = ((state >> XSHIFT) as u64) ^ (state as u64);
+ xsl.rotate_right(rot)
+}
+
+#[inline(always)]
+fn fill_bytes_impl<R: RngCore + ?Sized>(rng: &mut R, dest: &mut [u8]) {
+ let mut left = dest;
+ while left.len() >= 8 {
+ let (l, r) = {left}.split_at_mut(8);
+ left = r;
+ let chunk: [u8; 8] = rng.next_u64().to_le_bytes();
+ l.copy_from_slice(&chunk);
+ }
+ let n = left.len();
+ if n > 0 {
+ let chunk: [u8; 8] = rng.next_u64().to_le_bytes();
+ left.copy_from_slice(&chunk[..n]);
}
}
diff --git a/rand/rand_pcg/src/pcg64.rs b/rand/rand_pcg/src/pcg64.rs
index 9177ec2..fadc6dc 100644
--- a/rand/rand_pcg/src/pcg64.rs
+++ b/rand/rand_pcg/src/pcg64.rs
@@ -11,8 +11,8 @@
//! PCG random number generators
use core::fmt;
-use core::mem::transmute;
use rand_core::{RngCore, SeedableRng, Error, le, impls};
+#[cfg(feature="serde1")] use serde::{Serialize, Deserialize};
// This is the default multiplier used by PCG for 64-bit state.
const MULTIPLIER: u64 = 6364136223846793005;
@@ -45,7 +45,8 @@ impl Lcg64Xsh32 {
/// Note that PCG specifies default values for both parameters:
///
/// - `state = 0xcafef00dd15ea5e5`
- /// - `stream = 721347520444481703`
+ /// - `stream = 0xa02bdbf7bb3c0a7`
+ // Note: stream is 1442695040888963407u64 >> 1
pub fn new(state: u64, stream: u64) -> Self {
// The increment must be odd, hence we discard one bit:
let increment = (stream << 1) | 1;
@@ -115,27 +116,12 @@ impl RngCore for Lcg64Xsh32 {
#[inline]
fn fill_bytes(&mut self, dest: &mut [u8]) {
- // specialisation of impls::fill_bytes_via_next; approx 40% faster
- let mut left = dest;
- while left.len() >= 4 {
- let (l, r) = {left}.split_at_mut(4);
- left = r;
- let chunk: [u8; 4] = unsafe {
- transmute(self.next_u32().to_le())
- };
- l.copy_from_slice(&chunk);
- }
- let n = left.len();
- if n > 0 {
- let chunk: [u8; 4] = unsafe {
- transmute(self.next_u32().to_le())
- };
- left.copy_from_slice(&chunk[..n]);
- }
+ impls::fill_bytes_via_next(self, dest)
}
#[inline]
fn try_fill_bytes(&mut self, dest: &mut [u8]) -> Result<(), Error> {
- Ok(self.fill_bytes(dest))
+ self.fill_bytes(dest);
+ Ok(())
}
}
diff --git a/rand/rand_pcg/tests/lcg128xsl64.rs b/rand/rand_pcg/tests/lcg128xsl64.rs
new file mode 100644
index 0000000..efc72ff
--- /dev/null
+++ b/rand/rand_pcg/tests/lcg128xsl64.rs
@@ -0,0 +1,55 @@
+use rand_core::{RngCore, SeedableRng};
+use rand_pcg::{Lcg128Xsl64, Pcg64};
+
+#[test]
+fn test_lcg128xsl64_construction() {
+ // Test that various construction techniques produce a working RNG.
+ let seed = [1,2,3,4, 5,6,7,8, 9,10,11,12, 13,14,15,16,
+ 17,18,19,20, 21,22,23,24, 25,26,27,28, 29,30,31,32];
+ let mut rng1 = Lcg128Xsl64::from_seed(seed);
+ assert_eq!(rng1.next_u64(), 8740028313290271629);
+
+ let mut rng2 = Lcg128Xsl64::from_rng(&mut rng1).unwrap();
+ assert_eq!(rng2.next_u64(), 1922280315005786345);
+
+ let mut rng3 = Lcg128Xsl64::seed_from_u64(0);
+ assert_eq!(rng3.next_u64(), 2354861276966075475);
+
+ // This is the same as Lcg128Xsl64, so we only have a single test:
+ let mut rng4 = Pcg64::seed_from_u64(0);
+ assert_eq!(rng4.next_u64(), 2354861276966075475);
+}
+
+#[test]
+fn test_lcg128xsl64_true_values() {
+ // Numbers copied from official test suite (C version).
+ let mut rng = Lcg128Xsl64::new(42, 54);
+
+ let mut results = [0u64; 6];
+ for i in results.iter_mut() { *i = rng.next_u64(); }
+ let expected: [u64; 6] = [0x86b1da1d72062b68, 0x1304aa46c9853d39,
+ 0xa3670e9e0dd50358, 0xf9090e529a7dae00, 0xc85b9fd837996f2c, 0x606121f8e3919196];
+ assert_eq!(results, expected);
+}
+
+#[cfg(feature="serde1")]
+#[test]
+fn test_lcg128xsl64_serde() {
+ use bincode;
+ use std::io::{BufWriter, BufReader};
+
+ let mut rng = Lcg128Xsl64::seed_from_u64(0);
+
+ let buf: Vec<u8> = Vec::new();
+ let mut buf = BufWriter::new(buf);
+ bincode::serialize_into(&mut buf, &rng).expect("Could not serialize");
+
+ let buf = buf.into_inner().unwrap();
+ let mut read = BufReader::new(&buf[..]);
+ let mut deserialized: Lcg128Xsl64 = bincode::deserialize_from(&mut read)
+ .expect("Could not deserialize");
+
+ for _ in 0..16 {
+ assert_eq!(rng.next_u64(), deserialized.next_u64());
+ }
+}
diff --git a/rand/rand_pcg/tests/lcg64xsh32.rs b/rand/rand_pcg/tests/lcg64xsh32.rs
index 775b12c..e05bcc1 100644
--- a/rand/rand_pcg/tests/lcg64xsh32.rs
+++ b/rand/rand_pcg/tests/lcg64xsh32.rs
@@ -1,7 +1,3 @@
-extern crate rand_pcg;
-extern crate rand_core;
-#[cfg(all(feature="serde1", test))] extern crate bincode;
-
use rand_core::{RngCore, SeedableRng};
use rand_pcg::{Lcg64Xsh32, Pcg32};
diff --git a/rand/rand_pcg/tests/mcg128xsl64.rs b/rand/rand_pcg/tests/mcg128xsl64.rs
index 3279536..d58fa75 100644
--- a/rand/rand_pcg/tests/mcg128xsl64.rs
+++ b/rand/rand_pcg/tests/mcg128xsl64.rs
@@ -1,8 +1,3 @@
-#![cfg(rustc_1_26)]
-extern crate rand_pcg;
-extern crate rand_core;
-#[cfg(all(feature="serde1", test))] extern crate bincode;
-
use rand_core::{RngCore, SeedableRng};
use rand_pcg::{Mcg128Xsl64, Pcg64Mcg};