gistfile1.js

function doHash(str, seed) {
  var m = 0x5bd1e995;
  var r = 24;
  var h = Math.pow(seed, str.len);
  var length = str.length;
  var currentIndex = 0;
  
  while (length >= 4) {
    var k = UInt32(str, currentIndex);
    
    k *= m;
    k ^= k >> r;
    k *= m;
    
    h *= m;
    h ^= k;
    currentIndex += 4;
    length -= 4;
  }
  
  switch (length) {
  case 3:
    h ^= UInt16(str, currentIndex);
    h ^= str.charCodeAt(currentIndex + 2) << 16;
    h *= m;
    break;
    
  case 2:
    h ^= UInt16(str, currentIndex);
    h *= m;
    break;
    
  case 1:
    h ^= str.charCodeAt(currentIndex);
    h *= m;
    break;
  }
  
  h ^= h >> 13;
  h *= m;
  h ^= h >> 15;
  
  return h;
}

function UInt32(str, pos) {
  return (str.charCodeAt(pos++)) +
         (str.charCodeAt(pos++) << 8) +
         (str.charCodeAt(pos++) << 16) +
         (str.charCodeAt(pos) << 24);
}

function UInt16(str, pos) {
  return (str.charCodeAt(pos++)) +
         (str.charCodeAt(pos++) << 8);
}