pre.js

var Module = {
  'preRun': function() {
    var _shoco_compress = Module['cwrap']('shoco_compress', 'number', ['string', 'number', 'number', 'number']);
    var _shoco_decompress = Module['cwrap']('shoco_decompress', 'number', ['number', 'number', 'number', 'number']);

    var shoco = {
      'compress': function(str_in) {
        var out_heap = Module['_malloc'](str_in.length * 8);
        var out_buffer = new Uint8Array(Module['HEAPU8']['buffer'], out_heap, str_in.length * 8);

        var len = _shoco_compress(str_in, 0, out_buffer.byteOffset, out_buffer.byteLength);
        var result = new Uint8Array(out_buffer.subarray(0, len));

        Module['_free'](out_buffer.byteOffset);
        return result;
      },
      'decompress': function(cmp) {
        var out_heap = Module['_malloc'](cmp.length * 8);
        var out_buffer = new Uint8Array(Module['HEAPU8']['buffer'], out_heap, cmp.length * 8);

        var in_heap = Module['_malloc'](cmp.length);
        var in_buffer = new Uint8Array(Module['HEAPU8']['buffer'], in_heap, cmp.length);
        in_buffer.set(new Uint8Array(cmp.buffer));

        var len = _shoco_decompress(in_buffer.byteOffset, cmp.length, out_buffer.byteOffset, out_buffer.byteLength);
        var result = decodeURIComponent(escape(String.fromCharCode.apply(null, out_buffer.subarray(0, len))));

        Module['_free'](in_buffer.byteOffset);
        Module['_free'](out_buffer.byteOffset);
        return result;
      }
    }

    // node.js
    if (typeof module !== "undefined")
      module.exports = shoco;
    // browser
    else
      window['shoco'] = shoco;
  }
};