Implement std::io::Read for RngCore

pitdicker · pitdicker · commit 7959fbf63f6f · 2018-05-08T13:59:51.000+02:00
diff --git a/rand_core/src/lib.rs b/rand_core/src/lib.rs
@@ -439,3 +439,11 @@ impl<R: RngCore + ?Sized> RngCore for Box<R> {
         (**self).try_fill_bytes(dest)
     }
 }
+
+#[cfg(feature="std")]
+impl std::io::Read for RngCore {
+    fn read(&mut self, buf: &mut [u8]) -> Result<usize, std::io::Error> {
+        self.try_fill_bytes(buf)?;
+        Ok(buf.len())
+    }
+}

Original file line number	Diff line number	Diff line change
`@@ -439,3 +439,11 @@ impl<R: RngCore + ?Sized> RngCore for Box<R> {`
`439`	`439`	`(**self).try_fill_bytes(dest)`
`440`	`440`	`}`
`441`	`441`	`}`
	`442`	`+`
	`443`	`+#[cfg(feature="std")]`
	`444`	`+impl std::io::Read for RngCore {`
	`445`	`+ fn read(&mut self, buf: &mut [u8]) -> Result<usize, std::io::Error> {`
	`446`	`+ self.try_fill_bytes(buf)?;`
	`447`	`+ Ok(buf.len())`
	`448`	`+ }`
	`449`	`+}`