Contract Source Code:
File 1 of 1 : PlayToken
pragma solidity ^0.4.15;
/* TODO: change this to an interface definition as soon as truffle accepts it. See https://github.com/trufflesuite/truffle/issues/560 */
contract ITransferable {
function transfer(address _to, uint256 _value) public returns (bool success);
}
/**
@title PLAY Token
ERC20 Token with additional mint functionality.
A "controller" (initialized to the contract creator) has exclusive permission to mint.
The controller address can be changed until locked.
Implementation based on https://github.com/ConsenSys/Tokens
*/
contract PlayToken {
uint256 public totalSupply = 0;
string public name = "PLAY";
uint8 public decimals = 18;
string public symbol = "PLY";
string public version = '1';
address public controller;
bool public controllerLocked = false;
mapping (address => uint256) balances;
mapping (address => mapping (address => uint256)) allowed;
event Transfer(address indexed _from, address indexed _to, uint256 _value);
event Approval(address indexed _owner, address indexed _spender, uint256 _value);
modifier onlyController() {
require(msg.sender == controller);
_;
}
/** @dev constructor */
function PlayToken(address _controller) {
controller = _controller;
}
/** Sets a new controller address if the current controller isn't locked */
function setController(address _newController) onlyController {
require(! controllerLocked);
controller = _newController;
}
/** Locks the current controller address forever */
function lockController() onlyController {
controllerLocked = true;
}
/**
Creates new tokens for the given receiver.
Can be called only by the contract creator.
*/
function mint(address _receiver, uint256 _value) onlyController {
balances[_receiver] += _value;
totalSupply += _value;
// (probably) recommended by the standard, see https://github.com/ethereum/EIPs/pull/610/files#diff-c846f31381e26d8beeeae24afcdf4e3eR99
Transfer(0, _receiver, _value);
}
function transfer(address _to, uint256 _value) returns (bool success) {
/* Additional Restriction: don't accept token payments to the contract itself and to address 0 in order to avoid most
token losses by mistake - as is discussed in https://github.com/ethereum/EIPs/issues/223 */
require((_to != 0) && (_to != address(this)));
require(balances[msg.sender] >= _value);
balances[msg.sender] -= _value;
balances[_to] += _value;
Transfer(msg.sender, _to, _value);
return true;
}
function transferFrom(address _from, address _to, uint256 _value) returns (bool success) {
require(balances[_from] >= _value && allowed[_from][msg.sender] >= _value);
balances[_to] += _value;
balances[_from] -= _value;
allowed[_from][msg.sender] -= _value;
Transfer(_from, _to, _value);
return true;
}
function balanceOf(address _owner) constant returns (uint256 balance) {
return balances[_owner];
}
function approve(address _spender, uint256 _value) returns (bool success) {
allowed[msg.sender][_spender] = _value;
Approval(msg.sender, _spender, _value);
return true;
}
function allowance(address _owner, address _spender) constant returns (uint256 remaining) {
return allowed[_owner][_spender];
}
/* Approves and then calls the receiving contract */
function approveAndCall(address _spender, uint256 _value, bytes _extraData) returns (bool success) {
allowed[msg.sender][_spender] = _value;
Approval(msg.sender, _spender, _value);
/* call the receiveApproval function on the contract you want to be notified. This crafts the function signature manually so one doesn't have to include a contract in here just for this.
receiveApproval(address _from, uint256 _value, address _tokenContract, bytes _extraData)
it is assumed that when does this that the call *should* succeed, otherwise one would use vanilla approve instead. */
require(_spender.call(bytes4(bytes32(sha3("receiveApproval(address,uint256,address,bytes)"))), msg.sender, _value, this, _extraData));
return true;
}
/**
Withdraws tokens held by the contract to a given account.
Motivation: see https://github.com/ethereum/EIPs/issues/223#issuecomment-317987571
*/
function withdrawTokens(ITransferable _token, address _to, uint256 _amount) onlyController {
_token.transfer(_to, _amount);
}
}