initial commit for GitHub

core/codecBytes.js

@@ -0,0 +1,37 @@
+/** @fileOverview Bit array codec implementations.
+ *
+ * @author Emily Stark
+ * @author Mike Hamburg
+ * @author Dan Boneh
+ */
+
+/** @namespace Arrays of bytes */
+sjcl.codec.bytes = {
+  /** Convert from a bitArray to an array of bytes. */
+  fromBits: function (arr) {
+    var out = [], bl = sjcl.bitArray.bitLength(arr), i, tmp;
+    for (i=0; i<bl/8; i++) {
+      if ((i&3) === 0) {
+        tmp = arr[i/4];
+      }
+      out.push(tmp >>> 24);
+      tmp <<= 8;
+    }
+    return out;
+  },
+  /** Convert from an array of bytes to a bitArray. */
+  toBits: function (bytes) {
+    var out = [], i, tmp=0;
+    for (i=0; i<bytes.length; i++) {
+      tmp = tmp << 8 | bytes[i];
+      if ((i&3) === 3) {
+        out.push(tmp);
+        tmp = 0;
+      }
+    }
+    if (i&3) {
+      out.push(sjcl.bitArray.partial(8*(i&3), tmp));
+    }
+    return out;
+  }
+};