From a2b509656ac9c0f98d89fe4ea9d2f64a6ec7047a Mon Sep 17 00:00:00 2001
From: Huon Wilson <dbau.pp+github@gmail.com>
Date: Sat, 21 Sep 2013 22:06:50 +1000
Subject: std::rand: Add an implementation of ISAAC64.

This is 2x faster on 64-bit computers at generating anything larger
than 32-bits.

It has been verified against the canonical C implementation from the
website of the creator of ISAAC64.

Also, move `Rng.next` to `Rng.next_u32` and add `Rng.next_u64` to
take full advantage of the wider word width; otherwise Isaac64 will
always be squeezed down into a u32 wasting half the entropy and
offering no advantage over the 32-bit variant.
---
 src/libstd/rt/task.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

(limited to 'src/libstd/rt')

diff --git a/src/libstd/rt/task.rs b/src/libstd/rt/task.rs
index 2d1b57cebf5..48b894f51e0 100644
--- a/src/libstd/rt/task.rs
+++ b/src/libstd/rt/task.rs
@@ -509,7 +509,7 @@ mod test {
         do run_in_newsched_task() {
             use rand::{rng, Rng};
             let mut r = rng();
-            let _ = r.next();
+            let _ = r.next_u32();
         }
     }
 
-- 
cgit 1.4.1-3-g733a5


From 39a69d323da95ce642ea7fe8d40eb8bdd6a277c8 Mon Sep 17 00:00:00 2001
From: Huon Wilson <dbau.pp+github@gmail.com>
Date: Sun, 22 Sep 2013 20:51:57 +1000
Subject: std::rand: Add OSRng, ReaderRng wrappers around the OS RNG & generic
 Readers respectively.

The former reads from e.g. /dev/urandom, the latter just wraps any
std::rt::io::Reader into an interface that implements Rng.

This also adds Rng.fill_bytes for efficient implementations of the above
(reading 8 bytes at a time is inefficient when you can read 1000), and
removes the dependence on src/rt (i.e. rand_gen_seed) although this last
one requires implementing hand-seeding of the XorShiftRng used in the
scheduler on Linux/unixes, since OSRng relies on a scheduler existing to
be able to read from /dev/urandom.
---
 src/libstd/rand/mod.rs    | 122 ++++++++++++++++++++++-------
 src/libstd/rand/os.rs     | 193 ++++++++++++++++++++++++++++++++++++++++++++++
 src/libstd/rand/reader.rs |  94 ++++++++++++++++++++++
 src/libstd/rt/sched.rs    |  56 +++++++++++++-
 4 files changed, 435 insertions(+), 30 deletions(-)
 create mode 100644 src/libstd/rand/os.rs
 create mode 100644 src/libstd/rand/reader.rs

(limited to 'src/libstd/rt')

diff --git a/src/libstd/rand/mod.rs b/src/libstd/rand/mod.rs
index 237ffb0e9ad..e6bf42a5aed 100644
--- a/src/libstd/rand/mod.rs
+++ b/src/libstd/rand/mod.rs
@@ -44,24 +44,24 @@ fn main () {
 */
 
 use cast;
-use cmp;
 use container::Container;
 use int;
-use iter::{Iterator, range, range_step};
+use iter::{Iterator, range};
 use local_data;
 use prelude::*;
 use str;
-use sys;
 use u32;
 use u64;
 use uint;
 use vec;
-use libc::size_t;
 
 pub use self::isaac::{IsaacRng, Isaac64Rng};
+pub use self::os::OSRng;
 
 pub mod distributions;
 pub mod isaac;
+pub mod os;
+pub mod reader;
 
 /// A type that can be randomly generated using an Rng
 pub trait Rand {
@@ -233,15 +233,6 @@ impl<T: Rand + 'static> Rand for @T {
     fn rand<R: Rng>(rng: &mut R) -> @T { @rng.gen() }
 }
 
-#[abi = "cdecl"]
-pub mod rustrt {
-    use libc::size_t;
-
-    extern {
-        pub fn rand_gen_seed(buf: *mut u8, sz: size_t);
-    }
-}
-
 /// A value with a particular weight compared to other values
 pub struct Weighted<T> {
     /// The numerical weight of this item
@@ -252,7 +243,8 @@ pub struct Weighted<T> {
 
 /// A random number generator
 pub trait Rng {
-    /// Return the next random u32.
+    /// Return the next random u32. This rarely needs to be called
+    /// directly, prefer `r.gen()` to `r.next_u32()`.
     ///
     /// By default this is implemented in terms of `next_u64`. An
     /// implementation of this trait must provide at least one of
@@ -261,7 +253,8 @@ pub trait Rng {
         self.next_u64() as u32
     }
 
-    /// Return the next random u64.
+    /// Return the next random u64. This rarely needs to be called
+    /// directly, prefer `r.gen()` to `r.next_u64()`.
     ///
     /// By default this is implemented in terms of `next_u32`. An
     /// implementation of this trait must provide at least one of
@@ -270,6 +263,76 @@ pub trait Rng {
         (self.next_u32() as u64 << 32) | (self.next_u32() as u64)
     }
 
+    /// Fill `dest` with random data.
+    ///
+    /// This has a default implementation in terms of `next_u64` and
+    /// `next_u32`, but should be overriden by implementations that
+    /// offer a more efficient solution than just calling those
+    /// methods repeatedly.
+    ///
+    /// This method does *not* have a requirement to bear any fixed
+    /// relationship to the other methods, for example, it does *not*
+    /// have to result in the same output as progressively filling
+    /// `dest` with `self.gen::<u8>()`, and any such behaviour should
+    /// not be relied upon.
+    ///
+    /// This method should guarantee that `dest` is entirely filled
+    /// with new data, and may fail if this is impossible
+    /// (e.g. reading past the end of a file that is being used as the
+    /// source of randomness).
+    ///
+    /// # Example
+    ///
+    /// ~~~{.rust}
+    /// use std::rand::{task_rng, Rng};
+    ///
+    /// fn main() {
+    ///    let mut v = [0u8, .. 13579];
+    ///    task_rng().fill_bytes(v);
+    ///    printfln!(v);
+    /// }
+    /// ~~~
+    fn fill_bytes(&mut self, mut dest: &mut [u8]) {
+        // this relies on the lengths being transferred correctly when
+        // transmuting between vectors like this.
+        let as_u64: &mut &mut [u64] = unsafe { cast::transmute(&mut dest) };
+        for dest in as_u64.mut_iter() {
+            *dest = self.next_u64();
+        }
+
+        // the above will have filled up the vector as much as
+        // possible in multiples of 8 bytes.
+        let mut remaining = dest.len() % 8;
+
+        // space for a u32
+        if remaining >= 4 {
+            let as_u32: &mut &mut [u32] = unsafe { cast::transmute(&mut dest) };
+            as_u32[as_u32.len() - 1] = self.next_u32();
+            remaining -= 4;
+        }
+        // exactly filled
+        if remaining == 0 { return }
+
+        // now we know we've either got 1, 2 or 3 spots to go,
+        // i.e. exactly one u32 is enough.
+        let rand = self.next_u32();
+        let remaining_index = dest.len() - remaining;
+        match dest.mut_slice_from(remaining_index) {
+            [ref mut a] => {
+                *a = rand as u8;
+            }
+            [ref mut a, ref mut b] => {
+                *a = rand as u8;
+                *b = (rand >> 8) as u8;
+            }
+            [ref mut a, ref mut b, ref mut c] => {
+                *a = rand as u8;
+                *b = (rand >> 8) as u8;
+                *c = (rand >> 16) as u8;
+            }
+            _ => fail2!("Rng.fill_bytes: the impossible occurred: remaining != 1, 2 or 3")
+        }
+    }
 
     /// Return a random value of a Rand type.
     ///
@@ -630,11 +693,9 @@ impl XorShiftRng {
         // specific size, so we can just use a fixed buffer.
         let mut s = [0u8, ..16];
         loop {
-            do s.as_mut_buf |p, sz| {
-                unsafe {
-                    rustrt::rand_gen_seed(p, sz as size_t);
-                }
-            }
+            let mut r = OSRng::new();
+            r.fill_bytes(s);
+
             if !s.iter().all(|x| *x == 0) {
                 break;
             }
@@ -660,15 +721,10 @@ impl XorShiftRng {
 
 /// Create a new random seed of length `n`.
 pub fn seed(n: uint) -> ~[u8] {
-    #[fixed_stack_segment]; #[inline(never)];
-
-    unsafe {
-        let mut s = vec::from_elem(n as uint, 0_u8);
-        do s.as_mut_buf |p, sz| {
-            rustrt::rand_gen_seed(p, sz as size_t)
-        }
-        s
-    }
+    let mut s = vec::from_elem(n as uint, 0_u8);
+    let mut r = OSRng::new();
+    r.fill_bytes(s);
+    s
 }
 
 // used to make space in TLS for a random number generator
@@ -719,6 +775,14 @@ mod test {
     use option::{Option, Some};
     use super::*;
 
+    #[test]
+    fn test_fill_bytes_default() {
+        let mut r = weak_rng();
+
+        let mut v = [0u8, .. 100];
+        r.fill_bytes(v);
+    }
+
     #[test]
     fn test_gen_integer_range() {
         let mut r = rng();
diff --git a/src/libstd/rand/os.rs b/src/libstd/rand/os.rs
new file mode 100644
index 00000000000..0e6472b4d37
--- /dev/null
+++ b/src/libstd/rand/os.rs
@@ -0,0 +1,193 @@
+// 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.
+
+//! Interfaces to the operating system provided random number
+//! generators.
+
+use rand::Rng;
+use ops::Drop;
+
+#[cfg(unix)]
+use rand::reader::ReaderRng;
+#[cfg(unix)]
+use rt::io::{file, Open, Read};
+
+#[cfg(windows)]
+use ptr;
+#[cfg(windows)]
+use cast;
+#[cfg(windows)]
+use libc::{GetLastError, FALSE};
+
+/// A random number generator that retrieves randomness straight from
+/// the operating system. On Unix-like systems this reads from
+/// `/dev/urandom`, on Windows this uses `CryptGenRandom`.
+///
+/// This does not block.
+#[cfg(unix)]
+pub struct OSRng {
+    priv inner: ReaderRng<file::FileStream>
+}
+/// A random number generator that retrieves randomness straight from
+/// the operating system. On Unix-like systems this reads from
+/// `/dev/urandom`, on Windows this uses `CryptGenRandom`.
+///
+/// This does not block.
+///
+/// XXX: it is unlikely that this is threadsafe with the use of
+/// GetLastError.
+#[cfg(windows)]
+pub struct OSRng {
+    priv hcryptprov: raw::HCRYPTPROV
+}
+
+impl OSRng {
+    /// Create a new `OSRng`.
+    #[cfg(unix)]
+    pub fn new() -> OSRng {
+        let reader = file::open(& &"/dev/urandom", Open, Read).expect("Error opening /dev/urandom");
+        let reader_rng = ReaderRng::new(reader);
+
+        OSRng { inner: reader_rng }
+    }
+
+    /// Create a new `OSRng`.
+    #[cfg(windows)]
+    pub fn new() -> OSRng {
+        let hcp = ptr::mut_null();
+        // TODO these two 0 constants are incorrect!
+        if unsafe { raw::CryptAcquireContext(hcp, ptr::null(), ptr::null(), 0, 0); } == FALSE {
+            fail!("CryptAcquireContext failed with error %u", unsafe {GetLastError()})
+        }
+
+        OSRng { hcryptprov: hcp }
+    }
+}
+
+#[cfg(unix)]
+impl Rng for OSRng {
+    fn next_u32(&mut self) -> u32 {
+        self.inner.next_u32()
+    }
+    fn next_u64(&mut self) -> u64 {
+        self.inner.next_u64()
+    }
+    fn fill_bytes(&mut self, v: &mut [u8]) {
+        self.inner.fill_bytes(v)
+    }
+}
+
+#[cfg(windows)]
+impl Rng for OSRng {
+    fn next_u32(&mut self) -> u32 {
+        let mut v = [0u8, .. 4];
+        self.fill_bytes(v);
+        unsafe { cast::transmute(v) }
+    }
+    fn next_u64(&mut self) -> u64 {
+        let mut v = [0u8, .. 8];
+        self.fill_bytes(v);
+        unsafe { cast::transmute(v) }
+    }
+    fn fill_bytes(&mut self, v: &mut [u8]) {
+        if unsafe { raw::CryptGenRandom(self.hcryptprov, v.len(), v.unsafe_mut_ref(0)) } == FALSE {
+            fail!("CryptGenRandom failed with error %u", unsafe {GetLastError()})
+        }
+    }
+}
+
+impl Drop for OSRng {
+    #[cfg(unix)]
+    fn drop(&mut self) {
+        // ensure that OSRng is not implicitly copyable on all
+        // platforms, for consistency.
+    }
+
+    #[cfg(windows)]
+    fn drop(&mut self) {
+        // TODO this 0 means?
+        if unsafe { raw::CryptReleaseContext(self.hcryptprov, 0)} == FALSE {
+            fail!("CryptReleaseContext failed with error %u", unsafe {GetLastError()})
+        }
+    }
+}
+
+#[abi = "cdecl"]
+#[cfg(windows)]
+mod raw {
+    use libc::{LPCTSTR, DWORD, BOOL, BYTE};
+
+    enum HCRYPTPROV_opaque {}
+    pub type HCRYPTPROV = *CRYPTPROV;
+    extern {
+        pub fn CryptAcquireContext(phProv: *mut HCRYPTPROV,
+                                   pszContainer: LPCTSTR, pszProvider: LPCTSTR,
+                                   dwProvType: DWORD, dwFlags: DWORD) -> BOOL;
+        pub fn CryptGenRandom(hProv: HCRYPTPROV, dwLen: DWORD, pbBuffer: *mut BYTE) -> BOOL;
+        pub fn CryptReleaseContext(hProv: HCRYPTPROV, dwFlags: DWORD) -> BOOL;
+    }
+}
+
+#[cfg(test)]
+mod test {
+    use super::*;
+    use rand::Rng;
+
+    #[test]
+    fn test_os_rng() {
+        let mut r = OSRng::new();
+
+        r.next_u32();
+        r.next_u64();
+
+        let mut v = [0u8, .. 1000];
+        r.fill_bytes(v);
+    }
+
+    #[test]
+    fn test_os_rng_tasks() {
+        use task;
+        use comm;
+        use comm::{GenericChan, GenericPort};
+        use option::{None, Some};
+        use iter::{Iterator, range};
+        use vec::{ImmutableVector, OwnedVector};
+
+        let mut chans = ~[];
+        for _ in range(0, 20) {
+            let (p, c) = comm::stream();
+            chans.push(c);
+            do task::spawn_with(p) |p| {
+                // wait until all the tasks are ready to go.
+                p.recv();
+
+                // deschedule to attempt to interleave things as much
+                // as possible (XXX: is this a good test?)
+                let mut r = OSRng::new();
+                task::deschedule();
+                let mut v = [0u8, .. 1000];
+
+                for _ in range(0, 100) {
+                    r.next_u32();
+                    task::deschedule();
+                    r.next_u64();
+                    task::deschedule();
+                    r.fill_bytes(v);
+                    task::deschedule();
+                }
+            }
+        }
+
+        // start all the tasks
+        for c in chans.iter() {
+            c.send(())
+        }
+    }
+}
diff --git a/src/libstd/rand/reader.rs b/src/libstd/rand/reader.rs
new file mode 100644
index 00000000000..f1164346fe6
--- /dev/null
+++ b/src/libstd/rand/reader.rs
@@ -0,0 +1,94 @@
+// 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.
+
+use rt::io::Reader;
+use rt::io::ReaderByteConversions;
+
+use rand::Rng;
+
+/// An RNG that reads random bytes straight from a `Reader`. This will
+/// work best with an infinite reader, but this is not required. The
+/// semantics of reading past the end of the reader are the same as
+/// those of the `read` method of the inner `Reader`.
+pub struct ReaderRng<R> {
+    priv reader: R
+}
+
+impl<R: Reader> ReaderRng<R> {
+    /// Create a new `ReaderRng` from a `Reader`.
+    pub fn new(r: R) -> ReaderRng<R> {
+        ReaderRng {
+            reader: r
+        }
+    }
+}
+
+impl<R: Reader> Rng for ReaderRng<R> {
+    fn next_u32(&mut self) -> u32 {
+        // XXX which is better: consistency between big/little-endian
+        // platforms, or speed.
+        if cfg!(target_endian="little") {
+            self.reader.read_le_u32_()
+        } else {
+            self.reader.read_be_u32_()
+        }
+    }
+    fn next_u64(&mut self) -> u64 {
+        if cfg!(target_endian="little") {
+            self.reader.read_le_u64_()
+        } else {
+            self.reader.read_be_u64_()
+        }
+    }
+    fn fill_bytes(&mut self, v: &mut [u8]) {
+        // XXX: check that we filled `v``
+        let _n = self.reader.read(v);
+    }
+}
+
+#[cfg(test)]
+mod test {
+    use super::*;
+    use rt::io::mem::MemReader;
+    use cast;
+
+    #[test]
+    fn test_reader_rng_u64() {
+        // transmute from the target to avoid endianness concerns.
+        let v = ~[1u64, 2u64, 3u64];
+        let bytes: ~[u8] = unsafe {cast::transmute(v)};
+        let mut rng = ReaderRng::new(MemReader::new(bytes));
+
+        assert_eq!(rng.next_u64(), 1);
+        assert_eq!(rng.next_u64(), 2);
+        assert_eq!(rng.next_u64(), 3);
+    }
+    #[test]
+    fn test_reader_rng_u32() {
+        // transmute from the target to avoid endianness concerns.
+        let v = ~[1u32, 2u32, 3u32];
+        let bytes: ~[u8] = unsafe {cast::transmute(v)};
+        let mut rng = ReaderRng::new(MemReader::new(bytes));
+
+        assert_eq!(rng.next_u32(), 1);
+        assert_eq!(rng.next_u32(), 2);
+        assert_eq!(rng.next_u32(), 3);
+    }
+    #[test]
+    fn test_reader_rng_fill_bytes() {
+        let v = [1u8, 2, 3, 4, 5, 6, 7, 8];
+        let mut w = [0u8, .. 8];
+
+        let mut rng = ReaderRng::new(MemReader::new(v.to_owned()));
+        rng.fill_bytes(w);
+
+        assert_eq!(v, w);
+    }
+}
diff --git a/src/libstd/rt/sched.rs b/src/libstd/rt/sched.rs
index cbffec51cc9..004dab8d73a 100644
--- a/src/libstd/rt/sched.rs
+++ b/src/libstd/rt/sched.rs
@@ -140,7 +140,7 @@ impl Scheduler {
             cleanup_job: None,
             run_anything: run_anything,
             friend_handle: friend,
-            rng: XorShiftRng::new(),
+            rng: new_sched_rng(),
             idle_callback: None,
             yield_check_count: 0,
             steal_for_yield: false
@@ -844,6 +844,60 @@ impl ClosureConverter for UnsafeTaskReceiver {
     fn to_fn(self) -> &fn(&mut Scheduler, ~Task) { unsafe { transmute(self) } }
 }
 
+// On unix, we read randomness straight from /dev/urandom, but the
+// default constructor of an XorShiftRng does this via io::file, which
+// relies on the scheduler existing, so we have to manually load
+// randomness. Windows has its own C API for this, so we don't need to
+// worry there.
+#[cfg(windows)]
+fn new_sched_rng() -> XorShiftRng {
+    XorShiftRng::new()
+}
+#[cfg(unix)]
+#[fixed_stack_segment] #[inline(never)]
+fn new_sched_rng() -> XorShiftRng {
+    use libc;
+    use sys;
+    use c_str::ToCStr;
+    use ptr::RawPtr;
+    use vec::MutableVector;
+    use iter::Iterator;
+
+    // XXX: this could use io::native::file, when it works.
+    let file = do "/dev/urandom".with_c_str |name| {
+        do "r".with_c_str |mode| {
+            unsafe { libc::fopen(name, mode) }
+        }
+    };
+    if file.is_null() {
+        rtabort!("could not open /dev/urandom for reading.")
+    }
+
+    let mut seeds = [0u32, .. 4];
+    loop {
+        let nbytes = do seeds.as_mut_buf |buf, len| {
+            unsafe {
+                libc::fread(buf as *mut libc::c_void,
+                            sys::size_of::<u32>() as libc::size_t,
+                            len as libc::size_t,
+                            file)
+            }
+        };
+        rtassert!(nbytes == seeds.len() as libc::size_t);
+
+        if !seeds.iter().all(|x| *x == 0) {
+            break;
+        }
+    }
+
+    // XXX: do we need to guarantee that this is closed with a finally
+    // block (is that even possible without a scheduler?), or do we
+    // know that the only way that we can fail here is `abort`ing?
+    unsafe {libc::fclose(file);}
+
+    XorShiftRng::new_seeded(seeds[0], seeds[1], seeds[2], seeds[3])
+}
+
 #[cfg(test)]
 mod test {
     extern mod extra;
-- 
cgit 1.4.1-3-g733a5


From 92725ae765a75b139d5d5fc27305f4436dbb456e Mon Sep 17 00:00:00 2001
From: Huon Wilson <dbau.pp+github@gmail.com>
Date: Mon, 30 Sep 2013 01:29:28 +1000
Subject: std::rand: Add a trait for seeding RNGs: SeedableRng.

This provides 2 methods: .reseed() and ::from_seed that modify and
create respecitively.

Implement this trait for the RNGs in the stdlib for which this makes
sense.
---
 src/libextra/bitv.rs         |   4 +-
 src/libextra/treemap.rs      |   2 +-
 src/libstd/rand/isaac.rs     | 213 +++++++++++++++++++++++++++----------------
 src/libstd/rand/mod.rs       | 106 ++++++++++++++++-----
 src/libstd/rand/reseeding.rs |   4 +-
 src/libstd/rt/sched.rs       |   4 +-
 src/test/bench/core-map.rs   |   4 +-
 src/test/bench/core-set.rs   |   8 +-
 8 files changed, 232 insertions(+), 113 deletions(-)

(limited to 'src/libstd/rt')

diff --git a/src/libextra/bitv.rs b/src/libextra/bitv.rs
index 98f69425aee..4f8cd4d3308 100644
--- a/src/libextra/bitv.rs
+++ b/src/libextra/bitv.rs
@@ -1524,8 +1524,8 @@ mod tests {
     }
 
     fn rng() -> rand::IsaacRng {
-        let seed = [1, 2, 3, 4, 5, 6, 7, 8, 9, 0];
-        rand::IsaacRng::new_seeded(seed)
+        let seed = &[1, 2, 3, 4, 5, 6, 7, 8, 9, 0];
+        rand::SeedableRng::from_seed(seed)
     }
 
     #[bench]
diff --git a/src/libextra/treemap.rs b/src/libextra/treemap.rs
index ee7ba4a888b..66e1fd0c2c3 100644
--- a/src/libextra/treemap.rs
+++ b/src/libextra/treemap.rs
@@ -1013,7 +1013,7 @@ mod test_treemap {
         check_equal(ctrl, &map);
         assert!(map.find(&5).is_none());
 
-        let mut rng = rand::IsaacRng::new_seeded(&[42]);
+        let mut rng: rand::IsaacRng = rand::SeedableRng::from_seed(&[42]);
 
         do 3.times {
             do 90.times {
diff --git a/src/libstd/rand/isaac.rs b/src/libstd/rand/isaac.rs
index 534ebfb473b..6d338a922be 100644
--- a/src/libstd/rand/isaac.rs
+++ b/src/libstd/rand/isaac.rs
@@ -10,15 +10,10 @@
 
 //! The ISAAC random number generator.
 
-use rand::{seed, Rng};
-use iter::{Iterator, range, range_step};
+use rand::{seed, Rng, SeedableRng};
+use iter::{Iterator, range, range_step, Repeat};
 use option::{None, Some};
 
-use cast;
-use cmp;
-use sys;
-use vec;
-
 static RAND_SIZE_LEN: u32 = 8;
 static RAND_SIZE: u32 = 1 << RAND_SIZE_LEN;
 
@@ -38,30 +33,8 @@ pub struct IsaacRng {
 impl IsaacRng {
     /// Create an ISAAC random number generator with a random seed.
     pub fn new() -> IsaacRng {
-        IsaacRng::new_seeded(seed(RAND_SIZE as uint * 4))
-    }
-
-    /// Create an ISAAC random number generator with a seed. This can be any
-    /// length, although the maximum number of bytes used is 1024 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 the same seed.
-    pub fn new_seeded(seed: &[u8]) -> IsaacRng {
-        let mut rng = IsaacRng {
-            cnt: 0,
-            rsl: [0, .. RAND_SIZE],
-            mem: [0, .. RAND_SIZE],
-            a: 0, b: 0, c: 0
-        };
-
-        let array_size = sys::size_of_val(&rng.rsl);
-        let copy_length = cmp::min(array_size, seed.len());
-
-        // manually create a &mut [u8] slice of randrsl to copy into.
-        let dest = unsafe { cast::transmute((&mut rng.rsl, array_size)) };
-        vec::bytes::copy_memory(dest, seed, copy_length);
-        rng.init(true);
-        rng
+        let s = unsafe {seed::<u32>(RAND_SIZE as uint)};
+        SeedableRng::from_seed(s.as_slice())
     }
 
     /// Create an ISAAC random number generator using the default
@@ -197,6 +170,43 @@ impl Rng for IsaacRng {
     }
 }
 
+impl<'self> SeedableRng<&'self [u32]> for IsaacRng {
+    fn reseed(&mut self, seed: &'self [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::new(0u32));
+
+        for (rsl_elem, seed_elem) in self.rsl.mut_iter().zip(seed_iter) {
+            *rsl_elem = seed_elem;
+        }
+        self.cnt = 0;
+        self.a = 0;
+        self.b = 0;
+        self.c = 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: &'self [u32]) -> IsaacRng {
+        let mut rng = IsaacRng {
+            cnt: 0,
+            rsl: [0, .. RAND_SIZE],
+            mem: [0, .. RAND_SIZE],
+            a: 0, b: 0, c: 0
+        };
+
+        rng.reseed(seed);
+
+        rng
+    }
+}
+
+
 static RAND_SIZE_64_LEN: uint = 8;
 static RAND_SIZE_64: uint = 1 << RAND_SIZE_64_LEN;
 
@@ -218,31 +228,8 @@ impl Isaac64Rng {
     /// Create a 64-bit ISAAC random number generator with a random
     /// seed.
     pub fn new() -> Isaac64Rng {
-        Isaac64Rng::new_seeded(seed(RAND_SIZE_64 as uint * 8))
-    }
-
-    /// Create a 64-bit ISAAC random number generator with a
-    /// seed. This can be any length, although the maximum number of
-    /// bytes used is 2048 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
-    /// the same seed.
-    pub fn new_seeded(seed: &[u8]) -> Isaac64Rng {
-        let mut rng = Isaac64Rng {
-            cnt: 0,
-            rsl: [0, .. RAND_SIZE_64],
-            mem: [0, .. RAND_SIZE_64],
-            a: 0, b: 0, c: 0,
-        };
-
-        let array_size = sys::size_of_val(&rng.rsl);
-        let copy_length = cmp::min(array_size, seed.len());
-
-        // manually create a &mut [u8] slice of randrsl to copy into.
-        let dest = unsafe { cast::transmute((&mut rng.rsl, array_size)) };
-        vec::bytes::copy_memory(dest, seed, copy_length);
-        rng.init(true);
-        rng
+        let s = unsafe {seed::<u64>(RAND_SIZE_64)};
+        SeedableRng::from_seed(s.as_slice())
     }
 
     /// Create a 64-bit ISAAC random number generator using the
@@ -378,22 +365,58 @@ impl Rng for Isaac64Rng {
     }
 }
 
+impl<'self> SeedableRng<&'self [u64]> for Isaac64Rng {
+    fn reseed(&mut self, seed: &'self [u64]) {
+        // 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::new(0u64));
+
+        for (rsl_elem, seed_elem) in self.rsl.mut_iter().zip(seed_iter) {
+            *rsl_elem = seed_elem;
+        }
+        self.cnt = 0;
+        self.a = 0;
+        self.b = 0;
+        self.c = 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: &'self [u64]) -> Isaac64Rng {
+        let mut rng = Isaac64Rng {
+            cnt: 0,
+            rsl: [0, .. RAND_SIZE_64],
+            mem: [0, .. RAND_SIZE_64],
+            a: 0, b: 0, c: 0,
+        };
+        rng.reseed(seed);
+        rng
+    }
+}
+
 #[cfg(test)]
 mod test {
     use super::*;
-    use rand::{Rng, seed};
-    use option::{Option, Some};
+    use rand::{Rng, SeedableRng, seed};
+    use option::Some;
+    use iter::range;
+    use vec;
 
     #[test]
     fn test_rng_seeded() {
-        let seed = seed(1024);
-        let mut ra = IsaacRng::new_seeded(seed);
-        let mut rb = IsaacRng::new_seeded(seed);
+        let s = unsafe {seed::<u32>(256)};
+        let mut ra: IsaacRng = SeedableRng::from_seed(s.as_slice());
+        let mut rb: IsaacRng = SeedableRng::from_seed(s.as_slice());
         assert_eq!(ra.gen_ascii_str(100u), rb.gen_ascii_str(100u));
 
-        let seed = seed(2048);
-        let mut ra = Isaac64Rng::new_seeded(seed);
-        let mut rb = Isaac64Rng::new_seeded(seed);
+        let s = unsafe {seed::<u64>(256)};
+        let mut ra: Isaac64Rng = SeedableRng::from_seed(s.as_slice());
+        let mut rb: Isaac64Rng = SeedableRng::from_seed(s.as_slice());
         assert_eq!(ra.gen_ascii_str(100u), rb.gen_ascii_str(100u));
     }
 
@@ -401,29 +424,59 @@ mod test {
     fn test_rng_seeded_custom_seed() {
         // much shorter than generated seeds which are 1024 & 2048
         // bytes resp.
-        let seed = [2u8, 32u8, 4u8, 32u8, 51u8];
-        let mut ra = IsaacRng::new_seeded(seed);
-        let mut rb = IsaacRng::new_seeded(seed);
+        let seed = &[2, 32, 4, 32, 51];
+        let mut ra: IsaacRng = SeedableRng::from_seed(seed);
+        let mut rb: IsaacRng = SeedableRng::from_seed(seed);
         assert_eq!(ra.gen_ascii_str(100u), rb.gen_ascii_str(100u));
 
-        let mut ra = Isaac64Rng::new_seeded(seed);
-        let mut rb = Isaac64Rng::new_seeded(seed);
+        let seed = &[2, 32, 4, 32, 51];
+        let mut ra: Isaac64Rng = SeedableRng::from_seed(seed);
+        let mut rb: Isaac64Rng = SeedableRng::from_seed(seed);
         assert_eq!(ra.gen_ascii_str(100u), rb.gen_ascii_str(100u));
     }
 
     #[test]
-    fn test_rng_seeded_custom_seed2() {
-        let seed = [2u8, 32u8, 4u8, 32u8, 51u8];
-        let mut ra = IsaacRng::new_seeded(seed);
+    fn test_rng_32_true_values() {
+        let seed = &[2, 32, 4, 32, 51];
+        let mut ra: IsaacRng = SeedableRng::from_seed(seed);
         // Regression test that isaac is actually using the above vector
-        let r = ra.next_u32();
-        error2!("{:?}", r);
-        assert_eq!(r, 2935188040u32);
-
-        let mut ra = Isaac64Rng::new_seeded(seed);
+        let v = vec::from_fn(10, |_| ra.next_u32());
+        assert_eq!(v,
+                   ~[447462228, 2081944040, 3163797308, 2379916134, 2377489184,
+                     1132373754, 536342443, 2995223415, 1265094839, 345325140]);
+
+        let seed = &[500, -4000, 123456, 9876543, 1, 1, 1, 1, 1];
+        let mut rb: IsaacRng = SeedableRng::from_seed(seed);
+        // skip forward to the 10000th number
+        for _ in range(0, 10000) { rb.next_u32(); }
+
+        let v = vec::from_fn(10, |_| rb.next_u32());
+        assert_eq!(v,
+                   ~[612373032, 292987903, 1819311337, 3141271980, 422447569,
+                     310096395, 1083172510, 867909094, 2478664230, 2073577855]);
+    }
+    #[test]
+    fn test_rng_64_true_values() {
+        let seed = &[2, 32, 4, 32, 51];
+        let mut ra: Isaac64Rng = SeedableRng::from_seed(seed);
         // Regression test that isaac is actually using the above vector
-        let r = ra.next_u64();
-        error2!("{:?}", r);
-        assert!(r == 0 && r == 1); // FIXME: find true value
+        let v = vec::from_fn(10, |_| ra.next_u64());
+        assert_eq!(v,
+                   ~[15015576812873463115, 12461067598045625862, 14818626436142668771,
+                     5562406406765984441, 11813289907965514161, 13443797187798420053,
+                     6935026941854944442, 7750800609318664042, 14428747036317928637,
+                     14028894460301215947]);
+
+        let seed = &[500, -4000, 123456, 9876543, 1, 1, 1, 1, 1];
+        let mut rb: Isaac64Rng = SeedableRng::from_seed(seed);
+        // skip forward to the 10000th number
+        for _ in range(0, 10000) { rb.next_u64(); }
+
+        let v = vec::from_fn(10, |_| rb.next_u64());
+        assert_eq!(v,
+                   ~[13557216323596688637, 17060829581390442094, 4927582063811333743,
+                     2699639759356482270, 4819341314392384881, 6047100822963614452,
+                     11086255989965979163, 11901890363215659856, 5370800226050011580,
+                     16496463556025356451]);
     }
 }
diff --git a/src/libstd/rand/mod.rs b/src/libstd/rand/mod.rs
index 9fb6863692b..64f266d0045 100644
--- a/src/libstd/rand/mod.rs
+++ b/src/libstd/rand/mod.rs
@@ -638,6 +638,42 @@ pub trait Rng {
     }
 }
 
+/// A random number generator that can be explicitly seeded to produce
+/// the same stream of randomness multiple times.
+pub trait SeedableRng<Seed>: Rng {
+    /// Reseed an RNG with the given seed.
+    ///
+    /// # Example
+    ///
+    /// ```rust
+    /// use std::rand;
+    /// use std::rand::Rng;
+    ///
+    /// fn main() {
+    ///     let mut rng: rand::XorShiftRng = rand::SeedableRng::from_seed(&[1, 2, 3, 4]);
+    ///     println!("{}", rng.gen::<f64>());
+    ///     rng.reseed([5, 6, 7, 8]);
+    ///     println!("{}", rng.gen::<f64>());
+    /// }
+    /// ```
+    fn reseed(&mut self, Seed);
+
+    /// Create a new RNG with the given seed.
+    ///
+    /// # Example
+    ///
+    /// ```rust
+    /// use std::rand;
+    /// use std::rand::Rng;
+    ///
+    /// fn main() {
+    ///     let mut rng: rand::XorShiftRng = rand::SeedableRng::from_seed(&[1, 2, 3, 4]);
+    ///     println!("{}", rng.gen::<f64>());
+    /// }
+    /// ```
+    fn from_seed(seed: Seed) -> Self;
+}
+
 /// Create a random number generator with a default algorithm and seed.
 ///
 /// It returns the cryptographically-safest `Rng` algorithm currently
@@ -686,6 +722,18 @@ impl Rng for StdRng {
     }
 }
 
+impl<'self> SeedableRng<&'self [uint]> for StdRng {
+    fn reseed(&mut self, seed: &'self [uint]) {
+        // the internal RNG can just be seeded from the above
+        // randomness.
+        self.rng.reseed(unsafe {cast::transmute(seed)})
+    }
+
+    fn from_seed(seed: &'self [uint]) -> StdRng {
+        StdRng { rng: SeedableRng::from_seed(unsafe {cast::transmute(seed)}) }
+    }
+}
+
 /// Create a weak random number generator with a default algorithm and seed.
 ///
 /// It returns the fastest `Rng` algorithm currently available in Rust without
@@ -723,11 +771,35 @@ impl Rng for XorShiftRng {
     }
 }
 
+impl SeedableRng<[u32, .. 4]> for XorShiftRng {
+    /// Reseed an XorShiftRng. This will fail if `seed` is entirely 0.
+    fn reseed(&mut self, seed: [u32, .. 4]) {
+        assert!(!seed.iter().all(|&x| x == 0),
+                "XorShiftRng.reseed called with an all zero seed.");
+
+        self.x = seed[0];
+        self.y = seed[1];
+        self.z = seed[2];
+        self.w = seed[3];
+    }
+
+    /// Create a new XorShiftRng. This will fail if `seed` is entirely 0.
+    fn from_seed(seed: [u32, .. 4]) -> XorShiftRng {
+        assert!(!seed.iter().all(|&x| x == 0),
+                "XorShiftRng::from_seed called with an all zero seed.");
+
+        XorShiftRng {
+            x: seed[0],
+            y: seed[1],
+            z: seed[2],
+            w: seed[3]
+        }
+    }
+}
+
 impl XorShiftRng {
     /// Create an xor shift random number generator with a random seed.
     pub fn new() -> XorShiftRng {
-        #[fixed_stack_segment]; #[inline(never)];
-
         // generate seeds the same way as seed(), except we have a
         // specific size, so we can just use a fixed buffer.
         let mut s = [0u8, ..16];
@@ -740,29 +812,21 @@ impl XorShiftRng {
             }
         }
         let s: &[u32, ..4] = unsafe { cast::transmute(&s) };
-        XorShiftRng::new_seeded(s[0], s[1], s[2], s[3])
-    }
-
-    /**
-     * Create a random number generator using the specified seed. A generator
-     * constructed with a given seed will generate the same sequence of values
-     * as all other generators constructed with the same seed.
-     */
-    pub fn new_seeded(x: u32, y: u32, z: u32, w: u32) -> XorShiftRng {
-        XorShiftRng {
-            x: x,
-            y: y,
-            z: z,
-            w: w,
-        }
+        SeedableRng::from_seed(*s)
     }
 }
 
-/// Create a new random seed of length `n`.
-pub fn seed(n: uint) -> ~[u8] {
-    let mut s = vec::from_elem(n as uint, 0_u8);
+/// Create a new random seed of length `n`. This should only be used
+/// to create types for which *any* bit pattern is valid.
+pub unsafe fn seed<T: Clone>(n: uint) -> ~[T] {
+    use unstable::intrinsics;
+    let mut s = vec::from_elem(n, intrinsics::init());
     let mut r = OSRng::new();
-    r.fill_bytes(s);
+
+    {
+        let s_u8 = cast::transmute::<&mut [T], &mut [u8]>(s);
+        r.fill_bytes(s_u8);
+    }
     s
 }
 
diff --git a/src/libstd/rand/reseeding.rs b/src/libstd/rand/reseeding.rs
index d471a5e4e10..727efff0101 100644
--- a/src/libstd/rand/reseeding.rs
+++ b/src/libstd/rand/reseeding.rs
@@ -97,6 +97,8 @@ mod test {
     use super::*;
     use rand::Rng;
     use default::Default;
+    use iter::range;
+    use option::{None, Some};
 
     struct Counter {
         i: u32
@@ -117,7 +119,7 @@ mod test {
 
     #[test]
     fn test_reseeding() {
-        let mut rs = ReseedingRng::from_options(Counter {i:0}, 100, ReseedWithDefault);
+        let mut rs = ReseedingRng::new(Counter {i:0}, 400, ReseedWithDefault);
 
         let mut i = 0;
         for _ in range(0, 1000) {
diff --git a/src/libstd/rt/sched.rs b/src/libstd/rt/sched.rs
index 004dab8d73a..c1ca484754d 100644
--- a/src/libstd/rt/sched.rs
+++ b/src/libstd/rt/sched.rs
@@ -26,7 +26,7 @@ use rt::local::Local;
 use rt::rtio::{RemoteCallback, PausibleIdleCallback};
 use borrow::{to_uint};
 use cell::Cell;
-use rand::{XorShiftRng, Rng, Rand};
+use rand::{SeedableRng, XorShiftRng, Rng, Rand};
 use iter::range;
 use vec::{OwnedVector};
 
@@ -895,7 +895,7 @@ fn new_sched_rng() -> XorShiftRng {
     // know that the only way that we can fail here is `abort`ing?
     unsafe {libc::fclose(file);}
 
-    XorShiftRng::new_seeded(seeds[0], seeds[1], seeds[2], seeds[3])
+    SeedableRng::from_seed(seeds)
 }
 
 #[cfg(test)]
diff --git a/src/test/bench/core-map.rs b/src/test/bench/core-map.rs
index bec11ff3a7d..2d209e40e42 100644
--- a/src/test/bench/core-map.rs
+++ b/src/test/bench/core-map.rs
@@ -15,7 +15,7 @@ use extra::treemap::TreeMap;
 use std::hashmap::{HashMap, HashSet};
 use std::io;
 use std::os;
-use std::rand::Rng;
+use std::rand::{Rng, IsaacRng, SeedableRng};
 use std::trie::TrieMap;
 use std::uint;
 use std::vec;
@@ -106,7 +106,7 @@ fn main() {
     let mut rand = vec::with_capacity(n_keys);
 
     {
-        let mut rng = std::rand::IsaacRng::new_seeded([1, 1, 1, 1, 1, 1, 1]);
+        let mut rng: IsaacRng = SeedableRng::from_seed(&[1, 1, 1, 1, 1, 1, 1]);
         let mut set = HashSet::new();
         while set.len() != n_keys {
             let next = rng.gen();
diff --git a/src/test/bench/core-set.rs b/src/test/bench/core-set.rs
index 36ebdc54922..b9a8e74668f 100644
--- a/src/test/bench/core-set.rs
+++ b/src/test/bench/core-set.rs
@@ -163,11 +163,11 @@ fn main() {
         }
     };
 
-    let seed = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
+    let seed = &[1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
     let max = 200000;
 
     {
-        let mut rng = rand::IsaacRng::new_seeded(seed);
+        let mut rng: rand::IsaacRng = rand::SeedableRng::from_seed(seed);
         let mut results = empty_results();
         results.bench_int(&mut rng, num_keys, max, || {
             let s: HashSet<uint> = HashSet::new();
@@ -181,7 +181,7 @@ fn main() {
     }
 
     {
-        let mut rng = rand::IsaacRng::new_seeded(seed);
+        let mut rng: rand::IsaacRng = rand::SeedableRng::from_seed(seed);
         let mut results = empty_results();
         results.bench_int(&mut rng, num_keys, max, || {
             let s: TreeSet<uint> = TreeSet::new();
@@ -195,7 +195,7 @@ fn main() {
     }
 
     {
-        let mut rng = rand::IsaacRng::new_seeded(seed);
+        let mut rng: rand::IsaacRng = rand::SeedableRng::from_seed(seed);
         let mut results = empty_results();
         results.bench_int(&mut rng, num_keys, max, || BitvSet::new());
         write_results("extra::bitv::BitvSet", &results);
-- 
cgit 1.4.1-3-g733a5


From 29e3b33a0954f2494278d74344792f4b84a44120 Mon Sep 17 00:00:00 2001
From: Huon Wilson <dbau.pp+github@gmail.com>
Date: Wed, 2 Oct 2013 02:18:57 +1000
Subject: std::rand: make the windows OSRng more correct, remove some C++.

This lets the C++ code in the rt handle the (slightly) tricky parts of
random number generation: e.g. error detection/handling, and using the
values of the `#define`d options to the various functions.
---
 mk/rt.mk                  |  1 -
 src/libstd/rand/os.rs     | 45 ++++++++++---------------
 src/libstd/rand/reader.rs | 38 ++++++++++++++++++----
 src/libstd/rt/sched.rs    |  3 +-
 src/rt/rust_builtin.cpp   | 62 +++++++++++++++++++++++++++++++----
 src/rt/rust_rng.cpp       | 83 -----------------------------------------------
 src/rt/rust_rng.h         | 26 ---------------
 src/rt/rustrt.def.in      |  4 ++-
 8 files changed, 110 insertions(+), 152 deletions(-)
 delete mode 100644 src/rt/rust_rng.cpp
 delete mode 100644 src/rt/rust_rng.h

(limited to 'src/libstd/rt')

diff --git a/mk/rt.mk b/mk/rt.mk
index 5d75b961510..412e25bed4d 100644
--- a/mk/rt.mk
+++ b/mk/rt.mk
@@ -86,7 +86,6 @@ RUNTIME_CXXS_$(1)_$(2) := \
               rt/sync/lock_and_signal.cpp \
               rt/sync/rust_thread.cpp \
               rt/rust_builtin.cpp \
-              rt/rust_rng.cpp \
               rt/rust_upcall.cpp \
               rt/rust_uv.cpp \
               rt/miniz.cpp \
diff --git a/src/libstd/rand/os.rs b/src/libstd/rand/os.rs
index 0e6472b4d37..7a4e0aa95c6 100644
--- a/src/libstd/rand/os.rs
+++ b/src/libstd/rand/os.rs
@@ -19,12 +19,8 @@ use rand::reader::ReaderRng;
 #[cfg(unix)]
 use rt::io::{file, Open, Read};
 
-#[cfg(windows)]
-use ptr;
 #[cfg(windows)]
 use cast;
-#[cfg(windows)]
-use libc::{GetLastError, FALSE};
 
 /// A random number generator that retrieves randomness straight from
 /// the operating system. On Unix-like systems this reads from
@@ -40,9 +36,6 @@ pub struct OSRng {
 /// `/dev/urandom`, on Windows this uses `CryptGenRandom`.
 ///
 /// This does not block.
-///
-/// XXX: it is unlikely that this is threadsafe with the use of
-/// GetLastError.
 #[cfg(windows)]
 pub struct OSRng {
     priv hcryptprov: raw::HCRYPTPROV
@@ -60,12 +53,10 @@ impl OSRng {
 
     /// Create a new `OSRng`.
     #[cfg(windows)]
+    #[fixed_stack_segment] #[inline(never)]
     pub fn new() -> OSRng {
-        let hcp = ptr::mut_null();
-        // TODO these two 0 constants are incorrect!
-        if unsafe { raw::CryptAcquireContext(hcp, ptr::null(), ptr::null(), 0, 0); } == FALSE {
-            fail!("CryptAcquireContext failed with error %u", unsafe {GetLastError()})
-        }
+        let mut hcp = 0;
+        unsafe {raw::rust_win32_rand_acquire(&mut hcp)};
 
         OSRng { hcryptprov: hcp }
     }
@@ -96,9 +87,12 @@ impl Rng for OSRng {
         self.fill_bytes(v);
         unsafe { cast::transmute(v) }
     }
+    #[fixed_stack_segment] #[inline(never)]
     fn fill_bytes(&mut self, v: &mut [u8]) {
-        if unsafe { raw::CryptGenRandom(self.hcryptprov, v.len(), v.unsafe_mut_ref(0)) } == FALSE {
-            fail!("CryptGenRandom failed with error %u", unsafe {GetLastError()})
+        use libc::DWORD;
+
+        do v.as_mut_buf |ptr, len| {
+            unsafe {raw::rust_win32_rand_gen(self.hcryptprov, len as DWORD, ptr)}
         }
     }
 }
@@ -111,27 +105,24 @@ impl Drop for OSRng {
     }
 
     #[cfg(windows)]
+    #[fixed_stack_segment] #[inline(never)]
     fn drop(&mut self) {
-        // TODO this 0 means?
-        if unsafe { raw::CryptReleaseContext(self.hcryptprov, 0)} == FALSE {
-            fail!("CryptReleaseContext failed with error %u", unsafe {GetLastError()})
-        }
+        unsafe {raw::rust_win32_rand_release(self.hcryptprov)}
     }
 }
 
-#[abi = "cdecl"]
 #[cfg(windows)]
 mod raw {
-    use libc::{LPCTSTR, DWORD, BOOL, BYTE};
+    use libc::{c_long, DWORD, BYTE};
+
+    pub type HCRYPTPROV = c_long;
 
-    enum HCRYPTPROV_opaque {}
-    pub type HCRYPTPROV = *CRYPTPROV;
+    // these functions are implemented so that they either succeed or
+    // abort(), so we can just assume they work when we call them.
     extern {
-        pub fn CryptAcquireContext(phProv: *mut HCRYPTPROV,
-                                   pszContainer: LPCTSTR, pszProvider: LPCTSTR,
-                                   dwProvType: DWORD, dwFlags: DWORD) -> BOOL;
-        pub fn CryptGenRandom(hProv: HCRYPTPROV, dwLen: DWORD, pbBuffer: *mut BYTE) -> BOOL;
-        pub fn CryptReleaseContext(hProv: HCRYPTPROV, dwFlags: DWORD) -> BOOL;
+        pub fn rust_win32_rand_acquire(phProv: *mut HCRYPTPROV);
+        pub fn rust_win32_rand_gen(hProv: HCRYPTPROV, dwLen: DWORD, pbBuffer: *mut BYTE);
+        pub fn rust_win32_rand_release(hProv: HCRYPTPROV);
     }
 }
 
diff --git a/src/libstd/rand/reader.rs b/src/libstd/rand/reader.rs
index f1164346fe6..32a97100fa1 100644
--- a/src/libstd/rand/reader.rs
+++ b/src/libstd/rand/reader.rs
@@ -8,15 +8,28 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+use option::{Some, None};
 use rt::io::Reader;
 use rt::io::ReaderByteConversions;
 
 use rand::Rng;
 
 /// An RNG that reads random bytes straight from a `Reader`. This will
-/// work best with an infinite reader, but this is not required. The
-/// semantics of reading past the end of the reader are the same as
-/// those of the `read` method of the inner `Reader`.
+/// work best with an infinite reader, but this is not required.
+///
+/// It will fail if it there is insufficient data to fulfill a request.
+///
+/// # Example
+///
+/// ```rust
+/// use std::rand::reader;
+/// use std::rt::io::mem;
+///
+/// fn main() {
+///     let mut rng = reader::ReaderRng::new(mem::MemReader::new(~[1,2,3,4,5,6,7,8]));
+///     println!("{}", rng.gen::<uint>());
+/// }
+/// ```
 pub struct ReaderRng<R> {
     priv reader: R
 }
@@ -32,8 +45,6 @@ impl<R: Reader> ReaderRng<R> {
 
 impl<R: Reader> Rng for ReaderRng<R> {
     fn next_u32(&mut self) -> u32 {
-        // XXX which is better: consistency between big/little-endian
-        // platforms, or speed.
         if cfg!(target_endian="little") {
             self.reader.read_le_u32_()
         } else {
@@ -48,8 +59,13 @@ impl<R: Reader> Rng for ReaderRng<R> {
         }
     }
     fn fill_bytes(&mut self, v: &mut [u8]) {
-        // XXX: check that we filled `v``
-        let _n = self.reader.read(v);
+        if v.len() == 0 { return }
+        match self.reader.read(v) {
+            Some(n) if n == v.len() => return,
+            Some(n) => fail2!("ReaderRng.fill_bytes could not fill buffer: \
+                              read {} out of {} bytes.", n, v.len()),
+            None => fail2!("ReaderRng.fill_bytes reached eof.")
+        }
     }
 }
 
@@ -91,4 +107,12 @@ mod test {
 
         assert_eq!(v, w);
     }
+
+    #[test]
+    #[should_fail]
+    fn test_reader_rng_insufficient_bytes() {
+        let mut rng = ReaderRng::new(MemReader::new(~[]));
+        let mut v = [0u8, .. 3];
+        rng.fill_bytes(v);
+    }
 }
diff --git a/src/libstd/rt/sched.rs b/src/libstd/rt/sched.rs
index c1ca484754d..618921f8e08 100644
--- a/src/libstd/rt/sched.rs
+++ b/src/libstd/rt/sched.rs
@@ -26,7 +26,7 @@ use rt::local::Local;
 use rt::rtio::{RemoteCallback, PausibleIdleCallback};
 use borrow::{to_uint};
 use cell::Cell;
-use rand::{SeedableRng, XorShiftRng, Rng, Rand};
+use rand::{XorShiftRng, Rng, Rand};
 use iter::range;
 use vec::{OwnedVector};
 
@@ -862,6 +862,7 @@ fn new_sched_rng() -> XorShiftRng {
     use ptr::RawPtr;
     use vec::MutableVector;
     use iter::Iterator;
+    use rand::SeedableRng;
 
     // XXX: this could use io::native::file, when it works.
     let file = do "/dev/urandom".with_c_str |name| {
diff --git a/src/rt/rust_builtin.cpp b/src/rt/rust_builtin.cpp
index 34d1efd577d..d1d4286a7c6 100644
--- a/src/rt/rust_builtin.cpp
+++ b/src/rt/rust_builtin.cpp
@@ -15,7 +15,6 @@
 #include "sync/lock_and_signal.h"
 #include "memory_region.h"
 #include "boxed_region.h"
-#include "rust_rng.h"
 #include "vg/valgrind.h"
 #include "sp.h"
 
@@ -69,11 +68,6 @@ rust_env_pairs() {
 }
 #endif
 
-extern "C" CDECL void
-rand_gen_seed(uint8_t* dest, size_t size) {
-    rng_gen_seed(dest, size);
-}
-
 extern "C" CDECL char*
 #if defined(__WIN32__)
 rust_list_dir_val(WIN32_FIND_DATA* entry_ptr) {
@@ -654,6 +648,62 @@ rust_unset_sigprocmask() {
 
 #endif
 
+#if defined(__WIN32__)
+void
+win32_require(LPCTSTR fn, BOOL ok) {
+    if (!ok) {
+        LPTSTR buf;
+        DWORD err = GetLastError();
+        FormatMessage(FORMAT_MESSAGE_ALLOCATE_BUFFER |
+                      FORMAT_MESSAGE_FROM_SYSTEM |
+                      FORMAT_MESSAGE_IGNORE_INSERTS,
+                      NULL, err,
+                      MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
+                      (LPTSTR) &buf, 0, NULL );
+        fprintf(stderr, "%s failed with error %ld: %s", fn, err, buf);
+        LocalFree((HLOCAL)buf);
+        abort();
+    }
+}
+
+extern "C" CDECL void
+rust_win32_rand_acquire(HCRYPTPROV* phProv) {
+    win32_require
+        (_T("CryptAcquireContext"),
+         CryptAcquireContext(phProv, NULL, NULL, PROV_RSA_FULL,
+                             CRYPT_VERIFYCONTEXT|CRYPT_SILENT));
+
+}
+extern "C" CDECL void
+rust_win32_rand_gen(HCRYPTPROV hProv, DWORD dwLen, BYTE* pbBuffer) {
+    win32_require
+        (_T("CryptGenRandom"), CryptGenRandom(hProv, dwLen, pbBuffer));
+}
+extern "C" CDECL void
+rust_win32_rand_release(HCRYPTPROV hProv) {
+    win32_require
+        (_T("CryptReleaseContext"), CryptReleaseContext(hProv, 0));
+}
+
+#else
+
+// these symbols are listed in rustrt.def.in, so they need to exist; but they
+// should never be called.
+
+extern "C" CDECL void
+rust_win32_rand_acquire() {
+    abort();
+}
+extern "C" CDECL void
+rust_win32_rand_gen() {
+    abort();
+}
+extern "C" CDECL void
+rust_win32_rand_release() {
+    abort();
+}
+
+#endif
 //
 // Local Variables:
 // mode: C++
diff --git a/src/rt/rust_rng.cpp b/src/rt/rust_rng.cpp
deleted file mode 100644
index 89754f94b70..00000000000
--- a/src/rt/rust_rng.cpp
+++ /dev/null
@@ -1,83 +0,0 @@
-// Copyright 2012 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.
-
-#include "rust_globals.h"
-#include "rust_rng.h"
-#include "rust_util.h"
-
-
-#ifdef __WIN32__
-void
-win32_require(LPCTSTR fn, BOOL ok) {
-    if (!ok) {
-        LPTSTR buf;
-        DWORD err = GetLastError();
-        FormatMessage(FORMAT_MESSAGE_ALLOCATE_BUFFER |
-                      FORMAT_MESSAGE_FROM_SYSTEM |
-                      FORMAT_MESSAGE_IGNORE_INSERTS,
-                      NULL, err,
-                      MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
-                      (LPTSTR) &buf, 0, NULL );
-        fprintf(stderr, "%s failed with error %ld: %s", fn, err, buf);
-        LocalFree((HLOCAL)buf);
-        abort();
-    }
-}
-#endif
-
-void
-rng_gen_seed(uint8_t* dest, size_t size) {
-#ifdef __WIN32__
-    HCRYPTPROV hProv;
-    win32_require
-        (_T("CryptAcquireContext"),
-         CryptAcquireContext(&hProv, NULL, NULL, PROV_RSA_FULL,
-                             CRYPT_VERIFYCONTEXT|CRYPT_SILENT));
-    win32_require
-        (_T("CryptGenRandom"), CryptGenRandom(hProv, size, (BYTE*) dest));
-    win32_require
-        (_T("CryptReleaseContext"), CryptReleaseContext(hProv, 0));
-#else
-    int fd = open("/dev/urandom", O_RDONLY);
-    if (fd == -1) {
-        fprintf(stderr, "error opening /dev/urandom: %s", strerror(errno));
-        abort();
-    }
-    size_t amount = 0;
-    do {
-        ssize_t ret = read(fd, dest+amount, size-amount);
-        if (ret < 0) {
-            fprintf(stderr, "error reading /dev/urandom: %s", strerror(errno));
-            abort();
-        }
-        else if (ret == 0) {
-            fprintf(stderr, "somehow hit eof reading from /dev/urandom");
-            abort();
-        }
-        amount += (size_t)ret;
-    } while (amount < size);
-    int ret = close(fd);
-    if (ret != 0) {
-        fprintf(stderr, "error closing /dev/urandom: %s", strerror(errno));
-        // FIXME #3697: Why does this fail sometimes?
-        // abort();
-    }
-#endif
-}
-
-//
-// Local Variables:
-// mode: C++
-// fill-column: 78;
-// indent-tabs-mode: nil
-// c-basic-offset: 4
-// buffer-file-coding-system: utf-8-unix
-// End:
-//
diff --git a/src/rt/rust_rng.h b/src/rt/rust_rng.h
deleted file mode 100644
index 08335a6f73f..00000000000
--- a/src/rt/rust_rng.h
+++ /dev/null
@@ -1,26 +0,0 @@
-// Copyright 2012 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.
-
-#ifndef RUST_RNG_H
-#define RUST_RNG_H
-
-void rng_gen_seed(uint8_t* dest, size_t size);
-
-//
-// Local Variables:
-// mode: C++
-// fill-column: 78;
-// indent-tabs-mode: nil
-// c-basic-offset: 4
-// buffer-file-coding-system: utf-8-unix
-// End:
-//
-
-#endif
diff --git a/src/rt/rustrt.def.in b/src/rt/rustrt.def.in
index d0491a9c059..30f60c662e9 100644
--- a/src/rt/rustrt.def.in
+++ b/src/rt/rustrt.def.in
@@ -9,7 +9,6 @@ rust_localtime
 rust_timegm
 rust_mktime
 precise_time_ns
-rand_gen_seed
 rust_path_is_dir
 rust_path_exists
 rust_get_stdin
@@ -23,6 +22,9 @@ rust_log_console_off
 rust_should_log_console
 rust_unset_sigprocmask
 rust_env_pairs
+rust_win32_rand_acquire
+rust_win32_rand_gen
+rust_win32_rand_release
 upcall_rust_personality
 upcall_call_shim_on_c_stack
 upcall_call_shim_on_rust_stack
-- 
cgit 1.4.1-3-g733a5


From 5bb5f7678530c32caa11a1bc31e27187ff74bc19 Mon Sep 17 00:00:00 2001
From: Huon Wilson <dbau.pp+github@gmail.com>
Date: Tue, 8 Oct 2013 23:19:20 +1100
Subject: Convert rt::sched::new_sched_rng to use open/read/close rather than
 f*.

---
 src/libstd/rt/sched.rs | 26 ++++++++++----------------
 1 file changed, 10 insertions(+), 16 deletions(-)

(limited to 'src/libstd/rt')

diff --git a/src/libstd/rt/sched.rs b/src/libstd/rt/sched.rs
index 618921f8e08..e5cbadda23d 100644
--- a/src/libstd/rt/sched.rs
+++ b/src/libstd/rt/sched.rs
@@ -859,42 +859,36 @@ fn new_sched_rng() -> XorShiftRng {
     use libc;
     use sys;
     use c_str::ToCStr;
-    use ptr::RawPtr;
     use vec::MutableVector;
     use iter::Iterator;
     use rand::SeedableRng;
 
     // XXX: this could use io::native::file, when it works.
-    let file = do "/dev/urandom".with_c_str |name| {
-        do "r".with_c_str |mode| {
-            unsafe { libc::fopen(name, mode) }
-        }
+    let fd = do "/dev/urandom".with_c_str |name| {
+        unsafe { libc::open(name, libc::O_RDONLY, 0) }
     };
-    if file.is_null() {
+    if fd == -1 {
         rtabort!("could not open /dev/urandom for reading.")
     }
 
     let mut seeds = [0u32, .. 4];
+    let size = sys::size_of_val(&seeds);
     loop {
-        let nbytes = do seeds.as_mut_buf |buf, len| {
+        let nbytes = do seeds.as_mut_buf |buf, _| {
             unsafe {
-                libc::fread(buf as *mut libc::c_void,
-                            sys::size_of::<u32>() as libc::size_t,
-                            len as libc::size_t,
-                            file)
+                libc::read(fd,
+                           buf as *mut libc::c_void,
+                           size as libc::size_t)
             }
         };
-        rtassert!(nbytes == seeds.len() as libc::size_t);
+        rtassert!(nbytes as uint == size);
 
         if !seeds.iter().all(|x| *x == 0) {
             break;
         }
     }
 
-    // XXX: do we need to guarantee that this is closed with a finally
-    // block (is that even possible without a scheduler?), or do we
-    // know that the only way that we can fail here is `abort`ing?
-    unsafe {libc::fclose(file);}
+    unsafe {libc::close(fd);}
 
     SeedableRng::from_seed(seeds)
 }
-- 
cgit 1.4.1-3-g733a5


From e678435cab9cc8ddd668d4cb58ab82194c220382 Mon Sep 17 00:00:00 2001
From: Huon Wilson <dbau.pp+github@gmail.com>
Date: Wed, 9 Oct 2013 17:39:37 +1100
Subject: std::rand: Minor clean-up of comments & add a missing default method.

---
 src/libstd/rand/mod.rs | 7 +++++--
 src/libstd/rt/sched.rs | 1 -
 2 files changed, 5 insertions(+), 3 deletions(-)

(limited to 'src/libstd/rt')

diff --git a/src/libstd/rand/mod.rs b/src/libstd/rand/mod.rs
index aa4b496338d..9b757092266 100644
--- a/src/libstd/rand/mod.rs
+++ b/src/libstd/rand/mod.rs
@@ -648,8 +648,6 @@ impl SeedableRng<[u32, .. 4]> for XorShiftRng {
 impl XorShiftRng {
     /// Create an xor shift random number generator with a random seed.
     pub fn new() -> XorShiftRng {
-        // generate seeds the same way as seed(), except we have a
-        // specific size, so we can just use a fixed buffer.
         let mut s = [0u8, ..16];
         loop {
             let mut r = OSRng::new();
@@ -714,6 +712,11 @@ impl<R: Rng> Rng for @mut R {
     fn next_u64(&mut self) -> u64 {
         (**self).next_u64()
     }
+
+    #[inline]
+    fn fill_bytes(&mut self, bytes: &mut [u8]) {
+        (**self).fill_bytes(bytes);
+    }
 }
 
 /// Generate a random value using the task-local random number
diff --git a/src/libstd/rt/sched.rs b/src/libstd/rt/sched.rs
index e5cbadda23d..ee43ced44ab 100644
--- a/src/libstd/rt/sched.rs
+++ b/src/libstd/rt/sched.rs
@@ -863,7 +863,6 @@ fn new_sched_rng() -> XorShiftRng {
     use iter::Iterator;
     use rand::SeedableRng;
 
-    // XXX: this could use io::native::file, when it works.
     let fd = do "/dev/urandom".with_c_str |name| {
         unsafe { libc::open(name, libc::O_RDONLY, 0) }
     };
-- 
cgit 1.4.1-3-g733a5