Implement Threefish.

1 files changed, 8 insertions, 0 deletions

diff --git a/util.rkt b/util.rkt
index aa9714d..5f25e2e 100644
--- a/util.rkt
+++ b/util.rkt
@@ -20,6 +20,7 @@
 (provide integer->bytes
          integer->bytes/size
          bytes->integer
+         bytes->integer/le
          pad-bytes
          Justification
          Endianness
@@ -58,6 +59,13 @@
     (bitwise-ior (arithmetic-shift n 8)
                  byte)))
 
+(define: (bytes->integer/le [b : Bytes]) : Exact-Nonnegative-Integer
+  (for/fold: ([n : Exact-Nonnegative-Integer 0])
+             ([byte : Byte (in-bytes b)]
+              [i    : Integer (in-naturals)])
+    (bitwise-ior (arithmetic-shift byte (* i 8))
+                 n)))
+
 (define: (pad-bytes [b : Bytes]
                     [s : Exact-Nonnegative-Integer]
                     [fill : Byte]