Merge pull request #39 from gavofyork/gav

Add U512 type and a few conversions.

src/crypto.rs

@@ -1,4 +1,6 @@
 use hash::*;
+use bytes::*;
+use uint::*;
 use secp256k1::{key, Secp256k1};
 use rand::os::OsRng;
 
@@ -19,6 +21,11 @@ impl Signature {
 		ret[64] = v;
 		ret
 	}
+
+	/// Convert transaction to R, S and V components.
+	pub fn to_rsv(&self) -> (U256, U256, u8) {
+		(U256::from(&self.as_slice()[0..32]), U256::from(&self.as_slice()[32..64]), self[64])
+	}
 }
 
 #[derive(Debug)]

src/uint.rs

@@ -462,9 +462,73 @@ macro_rules! construct_uint {
 	);
 }
 
+construct_uint!(U512, 8);
 construct_uint!(U256, 4);
 construct_uint!(U128, 2);
 
+impl From<U256> for U512 {
+	fn from(value: U256) -> U512 {
+		let U256(ref arr) = value;
+		let mut ret = [0; 8];
+		ret[0] = arr[0];
+		ret[1] = arr[1];
+		ret[2] = arr[2];
+		ret[3] = arr[3];
+		U512(ret)
+	}
+}
+
+impl From<U512> for U256 {
+	fn from(value: U512) -> U256 {
+		let U512(ref arr) = value;
+		if arr[4] | arr[5] | arr[6] | arr[7] != 0 {
+			panic!("Overflow");
+		}
+		let mut ret = [0; 4];
+		ret[0] = arr[0];
+		ret[1] = arr[1];
+		ret[2] = arr[2];
+		ret[3] = arr[3];
+		U256(ret)
+	}
+}
+
+impl From<U256> for U128 {
+	fn from(value: U256) -> U128 {
+		let U256(ref arr) = value;
+		if arr[2] | arr[3] != 0 {
+			panic!("Overflow");
+		}
+		let mut ret = [0; 2];
+		ret[0] = arr[0];
+		ret[1] = arr[1];
+		U128(ret)
+	}
+}
+
+impl From<U512> for U128 {
+	fn from(value: U512) -> U128 {
+		let U512(ref arr) = value;
+		if arr[2] | arr[3] | arr[4] | arr[5] | arr[6] | arr[7] != 0 {
+			panic!("Overflow");
+		}
+		let mut ret = [0; 2];
+		ret[0] = arr[0];
+		ret[1] = arr[1];
+		U128(ret)
+	}
+}
+
+impl From<U128> for U512 {
+	fn from(value: U128) -> U512 {
+		let U128(ref arr) = value;
+		let mut ret = [0; 8];
+		ret[0] = arr[0];
+		ret[1] = arr[1];
+		U512(ret)
+	}
+}
+
 impl From<U128> for U256 {
 	fn from(value: U128) -> U256 {
 		let U128(ref arr) = value;