Initial commit!

src/unsigned/codec.rs

@@ -0,0 +1,70 @@
+pub trait Decoder {
+    fn from_bytes(x: &[u8]) -> Self;
+}
+
+pub trait Encoder {
+    fn to_bytes(&self) -> Vec<u8>;
+}
+
+pub(crate) fn raw_decoder(input: &[u8], output: &mut [u64])
+{
+    let mut item = 0;
+    let mut shift = 0;
+    let mut idx = 0;
+
+    for v in input.iter().rev() {
+        item |= (*v as u64) << shift;
+        shift += 8;
+        if shift == 64 {
+            shift = 0;
+            output[idx] = item;
+            idx += 1;
+            item = 0;
+        }
+    }
+    if item != 0 {
+        output[idx] = item;
+    }
+}
+
+macro_rules! generate_decoder {
+    ($name: ident) => {
+        impl Decoder for $name {
+            fn from_bytes(x: &[u8]) -> $name {
+                let mut res = $name::zero();
+                raw_decoder(x, &mut res.value);
+                res
+            }
+        }
+    }
+}
+
+macro_rules! generate_encoder {
+    ($name: ident) => {
+        impl Encoder for $name {
+            fn to_bytes(&self) -> Vec<u8> {
+                let mut res = Vec::with_capacity(self.value.len() * 8);
+                for v in self.value.iter().rev() {
+                    let val = *v;
+                    res.push( (val >> 56) as u8);
+                    res.push( (val >> 48) as u8);
+                    res.push( (val >> 40) as u8);
+                    res.push( (val >> 32) as u8);
+                    res.push( (val >> 24) as u8);
+                    res.push( (val >> 16) as u8);
+                    res.push( (val >>  8) as u8);
+                    res.push( (val >>  0) as u8);
+                }
+                res
+            }
+        }
+    }
+}
+
+macro_rules! generate_codec
+{
+    ($name: ident) => {
+        generate_decoder!($name);
+        generate_encoder!($name);
+    }
+}