文件 1 的 1:MintableToken.sol
pragma solidity ^0.4.19;
library SafeMath {
function mul(uint256 a, uint256 b) internal returns (uint256) {
uint256 c = a * b;
assert(a == 0 || c / a == b);
return c;
}
function div(uint256 a, uint256 b) internal returns (uint256) {
uint256 c = a / b;
return c;
}
function sub(uint256 a, uint256 b) internal returns (uint256) {
assert(b <= a);
return a - b;
}
function add(uint256 a, uint256 b) internal returns (uint256) {
uint256 c = a + b;
assert(c >= a);
return c;
}
}
contract ERC20Basic {
uint256 public totalSupply;
function balanceOf(address who) constant returns (uint256);
function transfer(address to, uint256 value);
event Transfer(address indexed from, address indexed to, uint256 value);
event Burn(address indexed from, uint256 value);
}
contract ERC20 is ERC20Basic {
function allowance(address owner, address spender) constant returns (uint256);
function transferFrom(address from, address to, uint256 value);
function approve(address spender, uint256 value);
event Approval(address indexed owner, address indexed spender, uint256 value);
}
contract BasicToken is ERC20Basic {
using SafeMath for uint256;
mapping(address => uint256) balances;
function transfer(address _to, uint256 _value) {
require ( balances[msg.sender] >= _value);
require ( balances[_to] + _value >= balances[_to]);
balances[msg.sender] = balances[msg.sender].sub(_value);
balances[_to] = balances[_to].add(_value);
Transfer(msg.sender, _to, _value);
}
function burn(uint256 _value) {
require ( balances[msg.sender] >= _value);
balances[msg.sender] = balances[msg.sender].sub(_value);
totalSupply = totalSupply.sub(_value);
Burn(msg.sender, _value);
}
function balanceOf(address _owner) constant returns (uint256 balance) {
return balances[_owner];
}
}
contract StandardToken is ERC20, BasicToken {
mapping (address => mapping (address => uint256)) allowed;
function transferFrom(address _from, address _to, uint256 _value) {
var _allowance = allowed[_from][msg.sender];
balances[_to] = balances[_to].add(_value);
balances[_from] = balances[_from].sub(_value);
allowed[_from][msg.sender] = _allowance.sub(_value);
Transfer(_from, _to, _value);
}
function approve(address _spender, uint256 _value) {
require ( !((_value !=0) && (allowed[msg.sender][_spender] !=0)));
allowed[msg.sender][_spender] = _value;
Approval(msg.sender, _spender, _value);
}
function allowance(address _owner, address _spender) constant returns (uint256 remaining) {
return allowed[_owner][_spender];
}
}
contract Ownable {
address public owner;
function Ownable() {
owner = msg.sender;
}
modifier onlyOwner() {
require(msg.sender == owner);
_;
}
function transferOwnership(address newOwner) onlyOwner {
if (newOwner != address(0)) {
owner = newOwner;
}
}
}
contract MintableToken is StandardToken, Ownable {
event Mint(address indexed to, uint256 amount);
event MintFinished();
string public name = "Electron World Money";
string public symbol = "EWM";
uint256 public decimals = 18;
bool public mintingFinished = false;
modifier canMint() {
require(!mintingFinished);
_;
}
function MintableToken() {
mint(msg.sender, 1000000000000000000000000000);
finishMinting();
}
function mint(address _to, uint256 _amount) onlyOwner canMint returns (bool) {
totalSupply = totalSupply.add(_amount);
balances[_to] = balances[_to].add(_amount);
Mint(_to, _amount);
Transfer(0, _to, _amount);
return true;
}
function finishMinting() onlyOwner returns (bool) {
mintingFinished = true;
MintFinished();
return true;
}
}
contract SwapToken is MintableToken {
MintableToken BasicToken;
mapping(address => bool) migrated;
function SwapToken (MintableToken _basicToken) {
BasicToken = _basicToken;
totalSupply = 1000000000000000000000000000;
}
function migration (address _owner) internal {
if (!migrated[_owner]) {
balances[_owner] = balances[_owner].add(BasicToken.balanceOf(_owner));
migrated[_owner] = true;
}
}
function transfer(address _to, uint256 _value) {
migration (msg.sender);
require ( balances[msg.sender] >= _value);
require ( balances[_to] + _value >= balances[_to]);
balances[msg.sender] = balances[msg.sender].sub(_value);
balances[_to] = balances[_to].add(_value);
Transfer(msg.sender, _to, _value);
}
function burn(uint256 _value) {
migration (msg.sender);
require ( balances[msg.sender] >= _value);
balances[msg.sender] = balances[msg.sender].sub(_value);
totalSupply = totalSupply.sub(_value);
Burn(msg.sender, _value);
}
function balanceOf(address _owner) constant returns (uint256 balance) {
migration(_owner);
return balances[_owner];
}
function transferFrom(address _from, address _to, uint256 _value) {
var _allowance = allowed[_from][msg.sender];
migration (msg.sender);
balances[_to] = balances[_to].add(_value);
balances[_from] = balances[_from].sub(_value);
allowed[_from][msg.sender] = _allowance.sub(_value);
Transfer(_from, _to, _value);
}
function approve(address _spender, uint256 _value) {
migration (msg.sender);
require ( !((_value != 0) && (allowed[msg.sender][_spender] != 0)));
allowed[msg.sender][_spender] = _value;
Approval(msg.sender, _spender, _value);
}
}
contract Crowdsale is Ownable {
using SafeMath for uint256;
MintableToken public token;
uint256 public deadline;
address public wallet;
uint256 public rate;
uint256 public weiRaised;
uint256 public tokensSold;
event TokenPurchase(address indexed purchaser, address indexed beneficiary, uint256 value, uint256 amount);
function Crowdsale(MintableToken tokenContract, uint256 durationInWeeks, uint256 _rate, address _wallet) {
require(_rate > 0);
require(_wallet != 0x0);
token = tokenContract;
deadline = now + durationInWeeks * 1 weeks;
rate = _rate;
wallet = _wallet;
}
function setNewTokenOwner(address newOwner) onlyOwner {
token.transferOwnership(newOwner);
}
function createTokenContract() internal returns (MintableToken) {
return new MintableToken();
}
function () payable {
buyTokens(msg.sender);
}
function buyTokens(address beneficiary) payable {
require(beneficiary != 0x0);
require(validPurchase());
uint256 weiAmount = msg.value;
uint256 updatedweiRaised = weiRaised.add(weiAmount);
uint256 tokens = weiAmount.mul(rate);
require ( tokens <= token.balanceOf(this) );
weiRaised = updatedweiRaised;
token.transfer(beneficiary, tokens);
tokensSold = tokensSold.add(tokens);
TokenPurchase(msg.sender, beneficiary, weiAmount, tokens);
forwardFunds();
}
function forwardFunds() internal {
wallet.transfer(msg.value);
}
function validPurchase() internal constant returns (bool) {
uint256 current = block.number;
bool withinPeriod = now <= deadline;
bool nonZeroPurchase = msg.value != 0;
return withinPeriod && nonZeroPurchase;
}
function hasEnded() public constant returns (bool) {
return ( now > deadline);
}
function tokenResend() onlyOwner {
token.transfer(owner, token.balanceOf(this));
}
}