github.com/klaytn/klaytn@v1.12.1/contracts/sc_erc20/ERC20ServiceChain.sol (about)

     1  // Copyright 2019 The klaytn Authors
     2  // This file is part of the klaytn library.
     3  //
     4  // The klaytn library is free software: you can redistribute it and/or modify
     5  // it under the terms of the GNU Lesser General Public License as published by
     6  // the Free Software Foundation, either version 3 of the License, or
     7  // (at your option) any later version.
     8  //
     9  // The klaytn library is distributed in the hope that it will be useful,
    10  // but WITHOUT ANY WARRANTY; without even the implied warranty of
    11  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
    12  // GNU Lesser General Public License for more details.
    13  //
    14  // You should have received a copy of the GNU Lesser General Public License
    15  // along with the klaytn library. If not, see <http://www.gnu.org/licenses/>.
    16  
    17  pragma solidity 0.5.6;
    18  
    19  import "../externals/openzeppelin-solidity/contracts/token/ERC20/ERC20.sol";
    20  import "../externals/openzeppelin-solidity/contracts/utils/Address.sol";
    21  import "../externals/openzeppelin-solidity/contracts/ownership/Ownable.sol";
    22  import "./IERC20BridgeReceiver.sol";
    23  
    24  
    25  /**
    26   * @title ERC20ServiceChain
    27   * @dev ERC20 service chain value transfer logic for 1-step transfer.
    28   */
    29  contract ERC20ServiceChain is ERC20, Ownable {
    30      using Address for address;
    31      address public bridge;
    32  
    33      constructor(address _bridge) internal {
    34          setBridge(_bridge);
    35      }
    36  
    37      function setBridge(address _bridge) public onlyOwner {
    38          if (!_bridge.isContract()) {
    39              revert("bridge is not a contract");
    40          }
    41          bridge = _bridge;
    42      }
    43  
    44      function requestValueTransfer(uint256 _amount, address _to, uint256 _feeLimit, bytes calldata _extraData) external {
    45          require(transfer(bridge, _amount.add(_feeLimit)), "requestValueTransfer: transfer failed");
    46          IERC20BridgeReceiver(bridge).onERC20Received(msg.sender, _to, _amount, _feeLimit, _extraData);
    47      }
    48  }