Add durandal::crc module

src/durandal/crc.rs

@@ -0,0 +1,18 @@
+fn crc_init() -> [u32; 256]
+{
+   let mut t = [0; 256];
+   for n in 0..256
+   {
+      t[n] = (0..8).fold(n as u32, |a, _|
+         {if a & 1 == 1 {0xedb88320 ^ a >> 1} else {a >> 1}});
+   }
+   t
+}
+
+pub fn crc32(b: &[u8], s: u32) -> u32
+{
+   let t = crc_init();
+   !b.iter().fold(s, |a, &o| {a >> 8 ^ t[(a & 0xff ^ o as u32) as usize]})
+}
+
+// EOF

src/durandal/mod.rs

@@ -2,9 +2,10 @@
 
 #[allow(dead_code)]
 pub mod bin;
-pub mod machead;
-pub mod text;
+pub mod crc;
 pub mod image;
+pub mod machead;
 pub mod pict;
+pub mod text;
 
 // EOF