From 2fcc36bbadcb8238ee292afc58c2cd460d1b69da Mon Sep 17 00:00:00 2001 From: Amir Bandeali Date: Tue, 26 Jun 2018 19:12:43 -0700 Subject: Update file structure --- .../src/2.0.0/tokens/ERC20Token/ERC20Token.sol | 99 ++++++++++++++++++++++ 1 file changed, 99 insertions(+) create mode 100644 packages/contracts/src/2.0.0/tokens/ERC20Token/ERC20Token.sol (limited to 'packages/contracts/src/2.0.0/tokens/ERC20Token/ERC20Token.sol') diff --git a/packages/contracts/src/2.0.0/tokens/ERC20Token/ERC20Token.sol b/packages/contracts/src/2.0.0/tokens/ERC20Token/ERC20Token.sol new file mode 100644 index 000000000..b6961a6ec --- /dev/null +++ b/packages/contracts/src/2.0.0/tokens/ERC20Token/ERC20Token.sol @@ -0,0 +1,99 @@ +/* + + Copyright 2018 ZeroEx Intl. + + Licensed under the Apache License, Version 2.0 (the "License"); + you may not use this file except in compliance with the License. + You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 + + Unless required by applicable law or agreed to in writing, software + distributed under the License is distributed on an "AS IS" BASIS, + WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + See the License for the specific language governing permissions and + limitations under the License. + +*/ + +pragma solidity ^0.4.24; +pragma experimental ABIEncoderV2; + +import "./IERC20Token.sol"; + +contract ERC20Token is IERC20Token { + + string constant INSUFFICIENT_BALANCE = "ERC20_INSUFFICIENT_BALANCE"; + string constant INSUFFICIENT_ALLOWANCE = "ERC20_INSUFFICIENT_ALLOWANCE"; + string constant OVERFLOW = "Transfer would result in an overflow."; + + mapping (address => uint256) balances; + mapping (address => mapping (address => uint256)) allowed; + + uint256 public totalSupply; + + function transfer(address _to, uint256 _value) + public + returns (bool) + { + require( + balances[msg.sender] >= _value, + INSUFFICIENT_BALANCE + ); + require( + balances[_to] + _value >= balances[_to], + OVERFLOW + ); + balances[msg.sender] -= _value; + balances[_to] += _value; + emit Transfer(msg.sender, _to, _value); + return true; + } + + function transferFrom(address _from, address _to, uint256 _value) + public + returns (bool) + { + require( + balances[_from] >= _value, + INSUFFICIENT_BALANCE + ); + require( + allowed[_from][msg.sender] >= _value, + INSUFFICIENT_ALLOWANCE + ); + require( + balances[_to] + _value >= balances[_to], + OVERFLOW + ); + balances[_to] += _value; + balances[_from] -= _value; + allowed[_from][msg.sender] -= _value; + emit Transfer(_from, _to, _value); + return true; + } + + function approve(address _spender, uint256 _value) + public + returns (bool) + { + allowed[msg.sender][_spender] = _value; + emit Approval(msg.sender, _spender, _value); + return true; + } + + function balanceOf(address _owner) + public view + returns (uint256) + { + return balances[_owner]; + } + + function allowance(address _owner, address _spender) + public + view + returns (uint256) + { + return allowed[_owner][_spender]; + } +} -- cgit v1.2.3