1 files changed, 44 insertions, 0 deletions
diff --git a/rand/rand_os/src/windows.rs b/rand/rand_os/src/windows.rs
new file mode 100644
index 0000000..6b06c7a
--- /dev/null
+++ b/rand/rand_os/src/windows.rs
@@ -0,0 +1,44 @@
+// Copyright 2018 Developers of the Rand project.
+//
+// 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.
+
+//! Implementation for Windows
+
+extern crate winapi;
+
+use rand_core::{Error, ErrorKind};
+use super::OsRngImpl;
+
+use std::io;
+
+use self::winapi::shared::minwindef::ULONG;
+use self::winapi::um::ntsecapi::RtlGenRandom;
+use self::winapi::um::winnt::PVOID;
+
+#[derive(Clone, Debug)]
+pub struct OsRng;
+
+impl OsRngImpl for OsRng {
+    fn new() -> Result<OsRng, Error> { Ok(OsRng) }
+
+    fn fill_chunk(&mut self, dest: &mut [u8]) -> Result<(), Error> {
+        let ret = unsafe {
+            RtlGenRandom(dest.as_mut_ptr() as PVOID, dest.len() as ULONG)
+        };
+        if ret == 0 {
+            return Err(Error::with_cause(
+                ErrorKind::Unavailable,
+                "couldn't generate random bytes",
+                io::Error::last_os_error()));
+        }
+        Ok(())
+    }
+
+    fn max_chunk_size(&self) -> usize { <ULONG>::max_value() as usize }
+
+    fn method_str(&self) -> &'static str { "RtlGenRandom" }
+}