utf8 js functions

utf8.js

var UTF8_MASK = [0x80,0xc0,0xe0,0xf0];


function utf8l(b){
  if (!(b & 0x80)) {
    return 1;
  } else if ((b & 0xE0) === 0xC0){
    return 2;
  } else if ((b & 0xF0) === 0xE0) {
    return 3;
  } else if ((b & 0xF8) === 0xF0) {
    return 4;  
  } else {
    return 0;
  }
}


// length,byte,character so far,number charater
function utf8c(l,b,c,n){
  c |= (b&~UTF8_MASK[l-1])<<(n-1)*6;
  return c;
}