Move ethcore files back into root.

util/src/sha3.rs

@@ -0,0 +1,59 @@
+//! Wrapper around tiny-keccak crate.
+
+use std::mem::uninitialized;
+use bytes::{BytesConvertable, Populatable};
+use hash::{H256, FixedHash};
+
+pub const SHA3_EMPTY: H256 = H256( [0xc5, 0xd2, 0x46, 0x01, 0x86, 0xf7, 0x23, 0x3c, 0x92, 0x7e, 0x7d, 0xb2, 0xdc, 0xc7, 0x03, 0xc0, 0xe5, 0x00, 0xb6, 0x53, 0xca, 0x82, 0x27, 0x3b, 0x7b, 0xfa, 0xd8, 0x04, 0x5d, 0x85, 0xa4, 0x70] );
+
+extern {
+	fn sha3_256(out: *mut u8, outlen: usize, input: *const u8, inputlen: usize) -> i32;
+}
+
+/// Types implementing this trait are sha3able.
+///
+/// ```
+/// extern crate ethcore_util as util;
+/// use std::str::FromStr;
+/// use util::sha3::*;
+/// use util::hash::*;
+///
+/// fn main() {
+/// 	assert_eq!([0u8; 0].sha3(), H256::from_str("c5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470").unwrap());
+/// }
+/// ```
+pub trait Hashable {
+	/// Calculate SHA3 of this object.
+	fn sha3(&self) -> H256;
+
+	/// Calculate SHA3 of this object and place result into dest.
+	fn sha3_into(&self, dest: &mut [u8]) {
+		self.sha3().copy_to(dest);
+	}
+}
+
+impl<T> Hashable for T where T: BytesConvertable {
+	fn sha3(&self) -> H256 {
+		unsafe {
+			let mut ret: H256 = uninitialized();
+			self.sha3_into(ret.as_slice_mut());
+			ret
+		}
+	}
+	fn sha3_into(&self, dest: &mut [u8]) {
+		unsafe {
+			let input: &[u8] = self.bytes();
+			sha3_256(dest.as_mut_ptr(), dest.len(), input.as_ptr(), input.len());
+		}
+	}
+}
+
+#[test]
+fn sha3_empty() {
+	assert_eq!([0u8; 0].sha3(), SHA3_EMPTY);
+}
+#[test]
+fn sha3_as() {
+	assert_eq!([0x41u8; 32].sha3(), From::from("59cad5948673622c1d64e2322488bf01619f7ff45789741b15a9f782ce9290a8"));
+}
+