Initial vendor packages

Signed-off-by: Valentin Popov <valentin@popov.link>

1 files changed, 328 insertions, 0 deletions

diff --git a/vendor/rand/src/prng/isaac.rs b/vendor/rand/src/prng/isaac.rs
new file mode 100644
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--- /dev/null
+++ b/vendor/rand/src/prng/isaac.rs
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+// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+//! The ISAAC random number generator.
+
+#![allow(non_camel_case_types)]
+
+use core::slice;
+use core::iter::repeat;
+use core::num::Wrapping as w;
+use core::fmt;
+
+use {Rng, SeedableRng, Rand};
+
+#[allow(bad_style)]
+type w32 = w<u32>;
+
+const RAND_SIZE_LEN: usize = 8;
+const RAND_SIZE: u32 = 1 << RAND_SIZE_LEN;
+const RAND_SIZE_USIZE: usize = 1 << RAND_SIZE_LEN;
+
+/// A random number generator that uses the ISAAC algorithm[1].
+///
+/// The ISAAC algorithm is generally accepted as suitable for
+/// cryptographic purposes, but this implementation has not be
+/// verified as such. Prefer a generator like `OsRng` that defers to
+/// the operating system for cases that need high security.
+///
+/// [1]: Bob Jenkins, [*ISAAC: A fast cryptographic random number
+/// generator*](http://www.burtleburtle.net/bob/rand/isaacafa.html)
+#[derive(Copy)]
+pub struct IsaacRng {
+    cnt: u32,
+    rsl: [w32; RAND_SIZE_USIZE],
+    mem: [w32; RAND_SIZE_USIZE],
+    a: w32,
+    b: w32,
+    c: w32,
+}
+
+static EMPTY: IsaacRng = IsaacRng {
+    cnt: 0,
+    rsl: [w(0); RAND_SIZE_USIZE],
+    mem: [w(0); RAND_SIZE_USIZE],
+    a: w(0), b: w(0), c: w(0),
+};
+
+impl IsaacRng {
+
+    /// Create an ISAAC random number generator using the default
+    /// fixed seed.
+    pub fn new_unseeded() -> IsaacRng {
+        let mut rng = EMPTY;
+        rng.init(false);
+        rng
+    }
+
+    /// Initialises `self`. If `use_rsl` is true, then use the current value
+    /// of `rsl` as a seed, otherwise construct one algorithmically (not
+    /// randomly).
+    fn init(&mut self, use_rsl: bool) {
+        let mut a = w(0x9e3779b9);
+        let mut b = a;
+        let mut c = a;
+        let mut d = a;
+        let mut e = a;
+        let mut f = a;
+        let mut g = a;
+        let mut h = a;
+
+        macro_rules! mix {
+            () => {{
+                a=a^(b<<11); d=d+a; b=b+c;
+                b=b^(c>>2);  e=e+b; c=c+d;
+                c=c^(d<<8);  f=f+c; d=d+e;
+                d=d^(e>>16); g=g+d; e=e+f;
+                e=e^(f<<10); h=h+e; f=f+g;
+                f=f^(g>>4);  a=a+f; g=g+h;
+                g=g^(h<<8);  b=b+g; h=h+a;
+                h=h^(a>>9);  c=c+h; a=a+b;
+            }}
+        }
+
+        for _ in 0..4 {
+            mix!();
+        }
+
+        if use_rsl {
+            macro_rules! memloop {
+                ($arr:expr) => {{
+                    for i in (0..RAND_SIZE_USIZE/8).map(|i| i * 8) {
+                        a=a+$arr[i  ]; b=b+$arr[i+1];
+                        c=c+$arr[i+2]; d=d+$arr[i+3];
+                        e=e+$arr[i+4]; f=f+$arr[i+5];
+                        g=g+$arr[i+6]; h=h+$arr[i+7];
+                        mix!();
+                        self.mem[i  ]=a; self.mem[i+1]=b;
+                        self.mem[i+2]=c; self.mem[i+3]=d;
+                        self.mem[i+4]=e; self.mem[i+5]=f;
+                        self.mem[i+6]=g; self.mem[i+7]=h;
+                    }
+                }}
+            }
+
+            memloop!(self.rsl);
+            memloop!(self.mem);
+        } else {
+            for i in (0..RAND_SIZE_USIZE/8).map(|i| i * 8) {
+                mix!();
+                self.mem[i  ]=a; self.mem[i+1]=b;
+                self.mem[i+2]=c; self.mem[i+3]=d;
+                self.mem[i+4]=e; self.mem[i+5]=f;
+                self.mem[i+6]=g; self.mem[i+7]=h;
+            }
+        }
+
+        self.isaac();
+    }
+
+    /// Refills the output buffer (`self.rsl`)
+    #[inline]
+    fn isaac(&mut self) {
+        self.c = self.c + w(1);
+        // abbreviations
+        let mut a = self.a;
+        let mut b = self.b + self.c;
+
+        const MIDPOINT: usize = RAND_SIZE_USIZE / 2;
+
+        macro_rules! ind {
+            ($x:expr) => ( self.mem[($x >> 2usize).0 as usize & (RAND_SIZE_USIZE - 1)] )
+        }
+
+        let r = [(0, MIDPOINT), (MIDPOINT, 0)];
+        for &(mr_offset, m2_offset) in r.iter() {
+
+            macro_rules! rngstepp {
+                ($j:expr, $shift:expr) => {{
+                    let base = $j;
+                    let mix = a << $shift;
+
+                    let x = self.mem[base  + mr_offset];
+                    a = (a ^ mix) + self.mem[base + m2_offset];
+                    let y = ind!(x) + a + b;
+                    self.mem[base + mr_offset] = y;
+
+                    b = ind!(y >> RAND_SIZE_LEN) + x;
+                    self.rsl[base + mr_offset] = b;
+                }}
+            }
+
+            macro_rules! rngstepn {
+                ($j:expr, $shift:expr) => {{
+                    let base = $j;
+                    let mix = a >> $shift;
+
+                    let x = self.mem[base  + mr_offset];
+                    a = (a ^ mix) + self.mem[base + m2_offset];
+                    let y = ind!(x) + a + b;
+                    self.mem[base + mr_offset] = y;
+
+                    b = ind!(y >> RAND_SIZE_LEN) + x;
+                    self.rsl[base + mr_offset] = b;
+                }}
+            }
+
+            for i in (0..MIDPOINT/4).map(|i| i * 4) {
+                rngstepp!(i + 0, 13);
+                rngstepn!(i + 1, 6);
+                rngstepp!(i + 2, 2);
+                rngstepn!(i + 3, 16);
+            }
+        }
+
+        self.a = a;
+        self.b = b;
+        self.cnt = RAND_SIZE;
+    }
+}
+
+// Cannot be derived because [u32; 256] does not implement Clone
+impl Clone for IsaacRng {
+    fn clone(&self) -> IsaacRng {
+        *self
+    }
+}
+
+impl Rng for IsaacRng {
+    #[inline]
+    fn next_u32(&mut self) -> u32 {
+        if self.cnt == 0 {
+            // make some more numbers
+            self.isaac();
+        }
+        self.cnt -= 1;
+
+        // self.cnt is at most RAND_SIZE, but that is before the
+        // subtraction above. We want to index without bounds
+        // checking, but this could lead to incorrect code if someone
+        // misrefactors, so we check, sometimes.
+        //
+        // (Changes here should be reflected in Isaac64Rng.next_u64.)
+        debug_assert!(self.cnt < RAND_SIZE);
+
+        // (the % is cheaply telling the optimiser that we're always
+        // in bounds, without unsafe. NB. this is a power of two, so
+        // it optimises to a bitwise mask).
+        self.rsl[(self.cnt % RAND_SIZE) as usize].0
+    }
+}
+
+impl<'a> SeedableRng<&'a [u32]> for IsaacRng {
+    fn reseed(&mut self, seed: &'a [u32]) {
+        // make the seed into [seed[0], seed[1], ..., seed[seed.len()
+        // - 1], 0, 0, ...], to fill rng.rsl.
+        let seed_iter = seed.iter().map(|&x| x).chain(repeat(0u32));
+
+        for (rsl_elem, seed_elem) in self.rsl.iter_mut().zip(seed_iter) {
+            *rsl_elem = w(seed_elem);
+        }
+        self.cnt = 0;
+        self.a = w(0);
+        self.b = w(0);
+        self.c = w(0);
+
+        self.init(true);
+    }
+
+    /// Create an ISAAC random number generator with a seed. This can
+    /// be any length, although the maximum number of elements used is
+    /// 256 and any more will be silently ignored. A generator
+    /// constructed with a given seed will generate the same sequence
+    /// of values as all other generators constructed with that seed.
+    fn from_seed(seed: &'a [u32]) -> IsaacRng {
+        let mut rng = EMPTY;
+        rng.reseed(seed);
+        rng
+    }
+}
+
+impl Rand for IsaacRng {
+    fn rand<R: Rng>(other: &mut R) -> IsaacRng {
+        let mut ret = EMPTY;
+        unsafe {
+            let ptr = ret.rsl.as_mut_ptr() as *mut u8;
+
+            let slice = slice::from_raw_parts_mut(ptr, RAND_SIZE_USIZE * 4);
+            other.fill_bytes(slice);
+        }
+        ret.cnt = 0;
+        ret.a = w(0);
+        ret.b = w(0);
+        ret.c = w(0);
+
+        ret.init(true);
+        return ret;
+    }
+}
+
+impl fmt::Debug for IsaacRng {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(f, "IsaacRng {{}}")
+    }
+}
+
+#[cfg(test)]
+mod test {
+    use {Rng, SeedableRng};
+    use super::IsaacRng;
+
+    #[test]
+    fn test_rng_32_rand_seeded() {
+        let s = ::test::rng().gen_iter::<u32>().take(256).collect::<Vec<u32>>();
+        let mut ra: IsaacRng = SeedableRng::from_seed(&s[..]);
+        let mut rb: IsaacRng = SeedableRng::from_seed(&s[..]);
+        assert!(::test::iter_eq(ra.gen_ascii_chars().take(100),
+                                rb.gen_ascii_chars().take(100)));
+    }
+
+    #[test]
+    fn test_rng_32_seeded() {
+        let seed: &[_] = &[1, 23, 456, 7890, 12345];
+        let mut ra: IsaacRng = SeedableRng::from_seed(seed);
+        let mut rb: IsaacRng = SeedableRng::from_seed(seed);
+        assert!(::test::iter_eq(ra.gen_ascii_chars().take(100),
+                                rb.gen_ascii_chars().take(100)));
+    }
+
+    #[test]
+    fn test_rng_32_reseed() {
+        let s = ::test::rng().gen_iter::<u32>().take(256).collect::<Vec<u32>>();
+        let mut r: IsaacRng = SeedableRng::from_seed(&s[..]);
+        let string1: String = r.gen_ascii_chars().take(100).collect();
+
+        r.reseed(&s[..]);
+
+        let string2: String = r.gen_ascii_chars().take(100).collect();
+        assert_eq!(string1, string2);
+    }
+
+    #[test]
+    fn test_rng_32_true_values() {
+        let seed: &[_] = &[1, 23, 456, 7890, 12345];
+        let mut ra: IsaacRng = SeedableRng::from_seed(seed);
+        // Regression test that isaac is actually using the above vector
+        let v = (0..10).map(|_| ra.next_u32()).collect::<Vec<_>>();
+        assert_eq!(v,
+                   vec!(2558573138, 873787463, 263499565, 2103644246, 3595684709,
+                        4203127393, 264982119, 2765226902, 2737944514, 3900253796));
+
+        let seed: &[_] = &[12345, 67890, 54321, 9876];
+        let mut rb: IsaacRng = SeedableRng::from_seed(seed);
+        // skip forward to the 10000th number
+        for _ in 0..10000 { rb.next_u32(); }
+
+        let v = (0..10).map(|_| rb.next_u32()).collect::<Vec<_>>();
+        assert_eq!(v,
+                   vec!(3676831399, 3183332890, 2834741178, 3854698763, 2717568474,
+                        1576568959, 3507990155, 179069555, 141456972, 2478885421));
+    }
+}