hexdump.js/hexdump.js

(function (exports) {
'use strict';

exports.hexdump = function hexdump(ab, offset, len, opts) {
  if (!opts) { opts = {}; }
  var ui8 = new Uint8Array(ab.buffer || ab, offset || ab.byteOffset, len || ab.byteLength);
  var bytecount = 0;
  var head = '        0  1  2  3  4  5  6  7  8  9  A  B  C  D  E  F';
  var trail;
  var str = [].slice.call(ui8).map(function (i) {
    var h = i.toString(16);
    if (h.length < 2) {
      h = '0' + h;
    }
    return h;
  }).join('').match(/.{1,2}/g).join(' ').match(/.{1,48}/g).map(function (str) {
    var lead = bytecount.toString(16);
    bytecount += 16;

    while (lead.length < 7) {
      lead = '0' + lead;
    }

    while (str.length < 48) {
      str += ' ';
    }

    if (opts.C) {
      return lead + ' ' + str + ' |' + str.replace(/ /g, '').match(/.{1,2}/g).map(function (ch) {
        var c = String.fromCharCode(parseInt(ch, 16));
        if (!/[ -~]/.test(c)) {
          c = '.';
        }
        return c;
      }).join('') + '|';
    } else {
      return lead + ' ' + str;
    }
  }).join('\n');

  trail = (len || ab.byteLength).toString(16);
  while (trail.length < 7) {
    trail = '0' + trail;
  }
  return head + '\n' + str + '\n' + trail;
};

}('undefined' !== typeof exports && exports || 'undefined' !== typeof window && window || global));