Contract Source Code:
File 1 of 1 : MaxToken
pragma solidity 0.4.24;
/**
* @title SafeMath
* @dev Math operations with safety checks that throw on error
*/
library SafeMath {
/**
* @dev Multiplies two numbers, throws on overflow.
*/
function mul(uint256 a, uint256 b) internal pure returns (uint256) {
if (a == 0) {
return 0;
}
uint256 c = a * b;
assert(c / a == b);
return c;
}
/**
* @dev Integer division of two numbers, truncating the quotient.
*/
function div(uint256 a, uint256 b) internal pure returns (uint256) {
// assert(b > 0); // Solidity automatically throws when dividing by 0
// uint256 c = a / b;
// assert(a == b * c + a % b); // There is no case in which this doesn't hold
return a / b;
}
/**
* @dev Subtracts two numbers, throws on overflow (i.e. if subtrahend is greater than minuend).
*/
function sub(uint256 a, uint256 b) internal pure returns (uint256) {
assert(b <= a);
return a - b;
}
/**
* @dev Adds two numbers, throws on overflow.
*/
function add(uint256 a, uint256 b) internal pure returns (uint256) {
uint256 c = a + b;
assert(c >= a);
return c;
}
function max64(uint64 a, uint64 b) internal pure returns (uint64) {
return a >= b ? a : b;
}
function min64(uint64 a, uint64 b) internal pure returns (uint64) {
return a < b ? a : b;
}
function max256(uint256 a, uint256 b) internal pure returns (uint256) {
return a >= b ? a : b;
}
function min256(uint256 a, uint256 b) internal pure returns (uint256) {
return a < b ? a : b;
}
}
/**
* @title ERC20Basic
* @dev Simpler version of ERC20 interface
* @dev see https://github.com/ethereum/EIPs/issues/179
*/
contract ERC20Basic {
function totalSupply() public view returns (uint256);
function balanceOf(address who) public view returns (uint256);
function transfer(address to, uint256 value) public returns (bool);
event Transfer(address indexed from, address indexed to, uint256 value);
}
/**
* @title Basic token
* @dev Basic version of StandardToken, with no allowances.
*/
contract BasicToken is ERC20Basic {
using SafeMath for uint256;
mapping(address => uint256) balances;
uint256 totalSupply_;
/**
* @dev total number of tokens in existence
*/
function totalSupply() public view returns (uint256) {
return totalSupply_;
}
/**
* @dev transfer token for a specified address
* @param _to The address to transfer to.
* @param _value The amount to be transferred.
*/
function transfer(address _to, uint256 _value) public returns (bool) {
require(_to != address(0));
require(_value <= balances[msg.sender]);
balances[msg.sender] = balances[msg.sender].sub(_value);
balances[_to] = balances[_to].add(_value);
emit Transfer(msg.sender, _to, _value);
return true;
}
/**
* @dev Gets the balance of the specified address.
* @param _owner The address to query the the balance of.
* @return An uint256 representing the amount owned by the passed address.
*/
function balanceOf(address _owner) public view returns (uint256 balance) {
return balances[_owner];
}
}
/**
* @title ERC20 interface
* @dev see https://github.com/ethereum/EIPs/issues/20
*/
contract ERC20 is ERC20Basic {
function allowance(address owner, address spender) public view returns (uint256);
function transferFrom(address from, address to, uint256 value) public returns (bool);
function approve(address spender, uint256 value) public returns (bool);
event Approval(address indexed owner, address indexed spender, uint256 value);
}
/**
* @title Standard ERC20 token
*
* @dev Implementation of the basic standard token.
* @dev https://github.com/ethereum/EIPs/issues/20
* @dev Based on code by FirstBlood:
* https://github.com/Firstbloodio/token/blob/master/smart_contract/FirstBloodToken.sol
*/
contract StandardToken is ERC20, BasicToken {
mapping (address => mapping (address => uint256)) internal allowed;
/**
* @dev Transfer tokens from one address to another
* @param _from address The address which you want to send tokens from
* @param _to address The address which you want to transfer to
* @param _value uint256 the amount of tokens to be transferred
*/
function transferFrom(address _from, address _to, uint256 _value) public returns (bool) {
require(_to != address(0));
require(_value <= balances[_from]);
require(_value <= allowed[_from][msg.sender]);
balances[_from] = balances[_from].sub(_value);
balances[_to] = balances[_to].add(_value);
allowed[_from][msg.sender] = allowed[_from][msg.sender].sub(_value);
emit Transfer(_from, _to, _value);
return true;
}
/**
* @dev Approve the passed address to spend the specified amount of tokens on behalf of msg.sender.
*
* Beware that changing an allowance with this method brings the risk that someone may use both the old
* and the new allowance by unfortunate transaction ordering. One possible solution to mitigate this
* race condition is to first reduce the spender's allowance to 0 and set the desired value afterwards:
* https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
* @param _spender The address which will spend the funds.
* @param _value The amount of tokens to be spent.
*/
function approve(address _spender, uint256 _value) public returns (bool) {
allowed[msg.sender][_spender] = _value;
emit Approval(msg.sender, _spender, _value);
return true;
}
/**
* @dev Function to check the amount of tokens that an owner allowed to a spender.
* @param _owner address The address which owns the funds.
* @param _spender address The address which will spend the funds.
* @return A uint256 specifying the amount of tokens still available for the spender.
*/
function allowance(address _owner, address _spender) public view returns (uint256) {
return allowed[_owner][_spender];
}
/**
* @dev Increase the amount of tokens that an owner allowed to a spender.
*
* approve should be called when allowed[_spender] == 0. To increment
* allowed value is better to use this function to avoid 2 calls (and wait until
* the first transaction is mined)
* From MonolithDAO Token.sol
* @param _spender The address which will spend the funds.
* @param _addedValue The amount of tokens to increase the allowance by.
*/
function increaseApproval(address _spender, uint _addedValue) public returns (bool) {
allowed[msg.sender][_spender] = allowed[msg.sender][_spender].add(_addedValue);
emit Approval(msg.sender, _spender, allowed[msg.sender][_spender]);
return true;
}
/**
* @dev Decrease the amount of tokens that an owner allowed to a spender.
*
* approve should be called when allowed[_spender] == 0. To decrement
* allowed value is better to use this function to avoid 2 calls (and wait until
* the first transaction is mined)
* From MonolithDAO Token.sol
* @param _spender The address which will spend the funds.
* @param _subtractedValue The amount of tokens to decrease the allowance by.
*/
function decreaseApproval(address _spender, uint _subtractedValue) public returns (bool) {
uint oldValue = allowed[msg.sender][_spender];
if (_subtractedValue > oldValue) {
allowed[msg.sender][_spender] = 0;
} else {
allowed[msg.sender][_spender] = oldValue.sub(_subtractedValue);
}
emit Approval(msg.sender, _spender, allowed[msg.sender][_spender]);
return true;
}
}
/**
* @title Ownable
* @dev The Ownable contract has an owner address, and provides basic authorization control
* functions, this simplifies the implementation of "user permissions".
*/
contract Ownable {
address public owner;
event OwnershipRenounced(address indexed previousOwner);
event OwnershipTransferred(
address indexed previousOwner,
address indexed newOwner
);
/**
* @dev The Ownable constructor sets the original `owner` of the contract to the sender
* account.
*/
constructor() public {
owner = msg.sender;
}
/**
* @dev Throws if called by any account other than the owner.
*/
modifier onlyOwner() {
require(msg.sender == owner);
_;
}
/**
* @dev Allows the current owner to transfer control of the contract to a newOwner.
* @param newOwner The address to transfer ownership to.
*/
function transferOwnership(address newOwner) public onlyOwner {
require(newOwner != address(0));
emit OwnershipTransferred(owner, newOwner);
owner = newOwner;
}
/**
* @dev Allows the current owner to relinquish control of the contract.
*/
function renounceOwnership() public onlyOwner {
emit OwnershipRenounced(owner);
owner = address(0);
}
}
/**
* @title Mintable token
* @dev Simple ERC20 Token example, with mintable token creation
* @dev Issue: * https://github.com/OpenZeppelin/zeppelin-solidity/issues/120
* Based on code by TokenMarketNet: https://github.com/TokenMarketNet/ico/blob/master/contracts/MintableToken.sol
*/
contract MintableToken is StandardToken, Ownable {
event Mint(address indexed to, uint256 amount);
event MintFinished();
bool public mintingFinished = false;
modifier canMint() {
require(!mintingFinished);
_;
}
/**
* @dev Function to mint tokens
* @param _to The address that will receive the minted tokens.
* @param _amount The amount of tokens to mint.
* @return A boolean that indicates if the operation was successful.
*/
function mint(address _to, uint256 _amount) public onlyOwner canMint returns (bool) {
totalSupply_ = totalSupply_.add(_amount);
balances[_to] = balances[_to].add(_amount);
emit Mint(_to, _amount);
emit Transfer(address(0), _to, _amount);
return true;
}
/**
* @dev Function to stop minting new tokens.
* @return True if the operation was successful.
*/
function finishMinting() public onlyOwner canMint returns (bool) {
mintingFinished = true;
emit MintFinished();
return true;
}
}
/**
* @title Capped token
* @dev Mintable token with a token cap.
*/
contract CappedToken is MintableToken {
uint256 public cap;
constructor(uint256 _cap) public {
require(_cap > 0);
cap = _cap;
}
/**
* @dev Function to mint tokens
* @param _to The address that will receive the minted tokens.
* @param _amount The amount of tokens to mint.
* @return A boolean that indicates if the operation was successful.
*/
function mint(address _to, uint256 _amount) public returns (bool) {
require(totalSupply_.add(_amount) <= cap);
return super.mint(_to, _amount);
}
}
/**
* @title Burnable Token
* @dev Token that can be irreversibly burned (destroyed).
*/
contract BurnableToken is StandardToken {
event Burn(address indexed burner, uint256 value);
/**
* @dev Burns a specific amount of tokens.
* @param _value The amount of token to be burned.
*/
function burn(uint256 _value) public {
_burn(msg.sender, _value);
}
function _burn(address _who, uint256 _value) internal {
require(_value <= balances[_who]);
// no need to require value <= totalSupply, since that would imply the
// sender's balance is greater than the totalSupply, which *should* be an assertion failure
balances[_who] = balances[_who].sub(_value);
totalSupply_ = totalSupply_.sub(_value);
emit Burn(_who, _value);
emit Transfer(_who, address(0), _value);
}
}
/**
* @title Pausable
* @dev Base contract which allows children to implement an emergency stop mechanism.
*/
contract Pausable is Ownable {
event Pause();
event Unpause();
bool public paused = false;
/**
* @dev Modifier to make a function callable only when the contract is not paused.
*/
modifier whenNotPaused() {
require(!paused);
_;
}
/**
* @dev Modifier to make a function callable only when the contract is paused.
*/
modifier whenPaused() {
require(paused);
_;
}
/**
* @dev called by the owner to pause, triggers stopped state
*/
function pause() public onlyOwner whenNotPaused {
paused = true;
emit Pause();
}
/**
* @dev called by the owner to unpause, returns to normal state
*/
function unpause() public onlyOwner whenPaused {
paused = false;
emit Unpause();
}
}
/**
* @title Pausable token
* @dev StandardToken modified with pausable transfers.
**/
contract PausableToken is StandardToken, Pausable {
function transfer(address _to, uint256 _value) public whenNotPaused returns (bool) {
return super.transfer(_to, _value);
}
function transferFrom(address _from, address _to, uint256 _value) public whenNotPaused returns (bool) {
return super.transferFrom(_from, _to, _value);
}
function approve(address _spender, uint256 _value) public whenNotPaused returns (bool) {
return super.approve(_spender, _value);
}
function increaseApproval(address _spender, uint _addedValue) public whenNotPaused returns (bool success) {
return super.increaseApproval(_spender, _addedValue);
}
function decreaseApproval(address _spender, uint _subtractedValue) public whenNotPaused returns (bool success) {
return super.decreaseApproval(_spender, _subtractedValue);
}
}
/**
* @title SafeERC20
* @dev Wrappers around ERC20 operations that throw on failure.
* To use this library you can add a `using SafeERC20 for ERC20;` statement to your contract,
* which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
*/
library SafeERC20 {
function safeTransfer(ERC20Basic token, address to, uint256 value) internal {
require(token.transfer(to, value));
}
function safeTransferFrom(
ERC20 token,
address from,
address to,
uint256 value
)
internal
{
require(token.transferFrom(from, to, value));
}
function safeApprove(ERC20 token, address spender, uint256 value) internal {
require(token.approve(spender, value));
}
}
/**
* @title TokenTimelock
* @dev TokenTimelock is a token holder contract that will allow a
* beneficiary to extract the tokens after a given release time
*/
contract TokenTimelock {
using SafeERC20 for ERC20Basic;
// ERC20 basic token contract being held
ERC20Basic public token;
// beneficiary of tokens after they are released
address public beneficiary;
// timestamp when token release is enabled
uint256 public releaseTime;
constructor(ERC20Basic _token, address _beneficiary, uint256 _releaseTime) public {
require(_releaseTime > block.timestamp); // solium-disable-line security/no-block-members
token = _token;
beneficiary = _beneficiary;
releaseTime = _releaseTime;
}
/**
* @notice Transfers tokens held by timelock to beneficiary.
*/
function release() public {
require(block.timestamp >= releaseTime); // solium-disable-line security/no-block-members
uint256 amount = token.balanceOf(this);
require(amount > 0);
token.safeTransfer(beneficiary, amount);
}
}
/**
* @title MaxToken
* @dev MaxToken Token contract
*/
contract MaxToken is PausableToken, CappedToken, BurnableToken {
using SafeMath for uint256;
string public name = "MAX Token";
string public symbol = "MAX";
uint public decimals = 18;
/**
* @dev The constructor sets the totol supply of the token
* account.
*/
constructor() public CappedToken(5e8 * 1e18) {
}
/**
* @dev mint timelocked tokens
*/
function mintTimelocked(address _to, uint256 _amount, uint256 _releaseTime) public
onlyOwner canMint returns (TokenTimelock)
{
TokenTimelock timelock = new TokenTimelock(this, _to, _releaseTime);
mint(timelock, _amount);
return timelock;
}
/**
* @dev Limit burn functions to owner and reduce cap after burning
*/
function _burn(address _who, uint256 _value) internal onlyOwner {
// no need to check _value <= cap since totalSupply <= cap and
// _value <= totalSupply was checked in burn functions
super._burn(_who, _value);
cap = cap.sub(_value);
}
}