SSTORE logic

gistfile1.txt

storageTrie.get(key, function(err, found) {
            if (found || (!found && val.toString('hex') === '00')) {
              gasLeft = gasLeft.add(100);
            } else if (!found && val.toString('hex') !== '00') {
              gasLeft = gasLeft.sub(100);
            } else if (found && val.toString('hex') === '00') {
              gasLeft = gasLeft.add(200);
            }

            if (val.toString('hex') === '00') {
              val = '';
            } else {
              val = rlp.encode(val);
            }

            storageTrie.put(key, val, function(){
              //update the stateRoot on the account
              opts.account.stateRoot = storageTrie.root;
              done();
            });
          });