Contract Name:
BurnableCrowdsaleToken
Contract Source Code:
File 1 of 1 : BurnableCrowdsaleToken
/**
* This smart contract code is Copyright 2017 TokenMarket Ltd. For more information see https://tokenmarket.net
*
* Licensed under the Apache License, version 2.0: https://github.com/TokenMarketNet/ico/blob/master/LICENSE.txt
*/
/**
* This smart contract code is Copyright 2017 TokenMarket Ltd. For more information see https://tokenmarket.net
*
* Licensed under the Apache License, version 2.0: https://github.com/TokenMarketNet/ico/blob/master/LICENSE.txt
*/
/**
* This smart contract code is Copyright 2017 TokenMarket Ltd. For more information see https://tokenmarket.net
*
* Licensed under the Apache License, version 2.0: https://github.com/TokenMarketNet/ico/blob/master/LICENSE.txt
*/
/**
* @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 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 c;
}
/**
* @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;
}
}
/**
* @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]);
// SafeMath.sub will throw if there is not enough balance.
balances[msg.sender] = balances[msg.sender].sub(_value);
balances[_to] = balances[_to].add(_value);
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);
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;
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);
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);
}
Approval(msg.sender, _spender, allowed[msg.sender][_spender]);
return true;
}
}
/**
* This smart contract code is Copyright 2017 TokenMarket Ltd. For more information see https://tokenmarket.net
*
* Licensed under the Apache License, version 2.0: https://github.com/TokenMarketNet/ico/blob/master/LICENSE.txt
*/
/**
* @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 OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
/**
* @dev The Ownable constructor sets the original `owner` of the contract to the sender
* account.
*/
function Ownable() 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));
OwnershipTransferred(owner, newOwner);
owner = newOwner;
}
}
contract Recoverable is Ownable {
/// @dev Empty constructor (for now)
function Recoverable() {
}
/// @dev This will be invoked by the owner, when owner wants to rescue tokens
/// @param token Token which will we rescue to the owner from the contract
function recoverTokens(ERC20Basic token) onlyOwner public {
token.transfer(owner, tokensToBeReturned(token));
}
/// @dev Interface function, can be overwritten by the superclass
/// @param token Token which balance we will check and return
/// @return The amount of tokens (in smallest denominator) the contract owns
function tokensToBeReturned(ERC20Basic token) public returns (uint) {
return token.balanceOf(this);
}
}
/**
* Standard EIP-20 token with an interface marker.
*
* @notice Interface marker is used by crowdsale contracts to validate that addresses point a good token contract.
*
*/
contract StandardTokenExt is StandardToken, Recoverable {
/* Interface declaration */
function isToken() public constant returns (bool weAre) {
return true;
}
}
contract BurnableToken is StandardTokenExt {
// @notice An address for the transfer event where the burned tokens are transferred in a faux Transfer event
address public constant BURN_ADDRESS = 0;
/** How many tokens we burned */
event Burned(address burner, uint burnedAmount);
/**
* Burn extra tokens from a balance.
*
*/
function burn(uint burnAmount) {
address burner = msg.sender;
balances[burner] = balances[burner].sub(burnAmount);
totalSupply_ = totalSupply_.sub(burnAmount);
Burned(burner, burnAmount);
// Inform the blockchain explores that track the
// balances only by a transfer event that the balance in this
// address has decreased
Transfer(burner, BURN_ADDRESS, burnAmount);
}
}
/**
* This smart contract code is Copyright 2017 TokenMarket Ltd. For more information see https://tokenmarket.net
*
* Licensed under the Apache License, version 2.0: https://github.com/TokenMarketNet/ico/blob/master/LICENSE.txt
*/
/**
* This smart contract code is Copyright 2017 TokenMarket Ltd. For more information see https://tokenmarket.net
*
* Licensed under the Apache License, version 2.0: https://github.com/TokenMarketNet/ico/blob/master/LICENSE.txt
*/
/**
* This smart contract code is Copyright 2017 TokenMarket Ltd. For more information see https://tokenmarket.net
*
* Licensed under the Apache License, version 2.0: https://github.com/TokenMarketNet/ico/blob/master/LICENSE.txt
*/
/**
* Upgrade agent interface inspired by Lunyr.
*
* Upgrade agent transfers tokens to a new contract.
* Upgrade agent itself can be the token contract, or just a middle man contract doing the heavy lifting.
*/
contract UpgradeAgent {
uint public originalSupply;
/** Interface marker */
function isUpgradeAgent() public constant returns (bool) {
return true;
}
function upgradeFrom(address _from, uint256 _value) public;
}
/**
* A token upgrade mechanism where users can opt-in amount of tokens to the next smart contract revision.
*
* First envisioned by Golem and Lunyr projects.
*/
contract UpgradeableToken is StandardTokenExt {
/** Contract / person who can set the upgrade path. This can be the same as team multisig wallet, as what it is with its default value. */
address public upgradeMaster;
/** The next contract where the tokens will be migrated. */
UpgradeAgent public upgradeAgent;
/** How many tokens we have upgraded by now. */
uint256 public totalUpgraded;
/**
* Upgrade states.
*
* - NotAllowed: The child contract has not reached a condition where the upgrade can bgun
* - WaitingForAgent: Token allows upgrade, but we don't have a new agent yet
* - ReadyToUpgrade: The agent is set, but not a single token has been upgraded yet
* - Upgrading: Upgrade agent is set and the balance holders can upgrade their tokens
*
*/
enum UpgradeState {Unknown, NotAllowed, WaitingForAgent, ReadyToUpgrade, Upgrading}
/**
* Somebody has upgraded some of his tokens.
*/
event Upgrade(address indexed _from, address indexed _to, uint256 _value);
/**
* New upgrade agent available.
*/
event UpgradeAgentSet(address agent);
/**
* Do not allow construction without upgrade master set.
*/
function UpgradeableToken(address _upgradeMaster) {
upgradeMaster = _upgradeMaster;
}
/**
* Allow the token holder to upgrade some of their tokens to a new contract.
*/
function upgrade(uint256 value) public {
UpgradeState state = getUpgradeState();
if(!(state == UpgradeState.ReadyToUpgrade || state == UpgradeState.Upgrading)) {
// Called in a bad state
throw;
}
// Validate input value.
if (value == 0) throw;
balances[msg.sender] = balances[msg.sender].sub(value);
// Take tokens out from circulation
totalSupply_ = totalSupply_.sub(value);
totalUpgraded = totalUpgraded.add(value);
// Upgrade agent reissues the tokens
upgradeAgent.upgradeFrom(msg.sender, value);
Upgrade(msg.sender, upgradeAgent, value);
}
/**
* Set an upgrade agent that handles
*/
function setUpgradeAgent(address agent) external {
if(!canUpgrade()) {
// The token is not yet in a state that we could think upgrading
throw;
}
if (agent == 0x0) throw;
// Only a master can designate the next agent
if (msg.sender != upgradeMaster) throw;
// Upgrade has already begun for an agent
if (getUpgradeState() == UpgradeState.Upgrading) throw;
upgradeAgent = UpgradeAgent(agent);
// Bad interface
if(!upgradeAgent.isUpgradeAgent()) throw;
// Make sure that token supplies match in source and target
if (upgradeAgent.originalSupply() != totalSupply_) throw;
UpgradeAgentSet(upgradeAgent);
}
/**
* Get the state of the token upgrade.
*/
function getUpgradeState() public constant returns(UpgradeState) {
if(!canUpgrade()) return UpgradeState.NotAllowed;
else if(address(upgradeAgent) == 0x00) return UpgradeState.WaitingForAgent;
else if(totalUpgraded == 0) return UpgradeState.ReadyToUpgrade;
else return UpgradeState.Upgrading;
}
/**
* Change the upgrade master.
*
* This allows us to set a new owner for the upgrade mechanism.
*/
function setUpgradeMaster(address master) public {
if (master == 0x0) throw;
if (msg.sender != upgradeMaster) throw;
upgradeMaster = master;
}
/**
* Child contract can enable to provide the condition when the upgrade can begun.
*/
function canUpgrade() public constant returns(bool) {
return true;
}
}
/**
* This smart contract code is Copyright 2017 TokenMarket Ltd. For more information see https://tokenmarket.net
*
* Licensed under the Apache License, version 2.0: https://github.com/TokenMarketNet/ico/blob/master/LICENSE.txt
*/
/**
* Define interface for releasing the token transfer after a successful crowdsale.
*/
contract ReleasableToken is StandardTokenExt {
/* The finalizer contract that allows unlift the transfer limits on this token */
address public releaseAgent;
/** A crowdsale contract can release us to the wild if ICO success. If false we are are in transfer lock up period.*/
bool public released = false;
/** Map of agents that are allowed to transfer tokens regardless of the lock down period. These are crowdsale contracts and possible the team multisig itself. */
mapping (address => bool) public transferAgents;
/**
* Limit token transfer until the crowdsale is over.
*
*/
modifier canTransfer(address _sender) {
if(!released) {
if(!transferAgents[_sender]) {
throw;
}
}
_;
}
/**
* Set the contract that can call release and make the token transferable.
*
* Design choice. Allow reset the release agent to fix fat finger mistakes.
*/
function setReleaseAgent(address addr) onlyOwner inReleaseState(false) public {
// We don't do interface check here as we might want to a normal wallet address to act as a release agent
releaseAgent = addr;
}
/**
* Owner can allow a particular address (a crowdsale contract) to transfer tokens despite the lock up period.
*/
function setTransferAgent(address addr, bool state) onlyOwner inReleaseState(false) public {
transferAgents[addr] = state;
}
/**
* One way function to release the tokens to the wild.
*
* Can be called only from the release agent that is the final ICO contract. It is only called if the crowdsale has been success (first milestone reached).
*/
function releaseTokenTransfer() public onlyReleaseAgent {
released = true;
}
/** The function can be called only before or after the tokens have been releasesd */
modifier inReleaseState(bool releaseState) {
if(releaseState != released) {
throw;
}
_;
}
/** The function can be called only by a whitelisted release agent. */
modifier onlyReleaseAgent() {
if(msg.sender != releaseAgent) {
throw;
}
_;
}
function transfer(address _to, uint _value) canTransfer(msg.sender) returns (bool success) {
// Call StandardToken.transfer()
return super.transfer(_to, _value);
}
function transferFrom(address _from, address _to, uint _value) canTransfer(_from) returns (bool success) {
// Call StandardToken.transferForm()
return super.transferFrom(_from, _to, _value);
}
}
/**
* This smart contract code is Copyright 2017 TokenMarket Ltd. For more information see https://tokenmarket.net
*
* Licensed under the Apache License, version 2.0: https://github.com/TokenMarketNet/ico/blob/master/LICENSE.txt
*/
/**
* This smart contract code is Copyright 2017 TokenMarket Ltd. For more information see https://tokenmarket.net
*
* Licensed under the Apache License, version 2.0: https://github.com/TokenMarketNet/ico/blob/master/LICENSE.txt
*/
/**
* Safe unsigned safe math.
*
* https://blog.aragon.one/library-driven-development-in-solidity-2bebcaf88736#.750gwtwli
*
* Originally from https://raw.githubusercontent.com/AragonOne/zeppelin-solidity/master/contracts/SafeMathLib.sol
*
* Maintained here until merged to mainline zeppelin-solidity.
*
*/
library SafeMathLib {
function times(uint a, uint b) returns (uint) {
uint c = a * b;
assert(a == 0 || c / a == b);
return c;
}
function minus(uint a, uint b) returns (uint) {
assert(b <= a);
return a - b;
}
function plus(uint a, uint b) returns (uint) {
uint c = a + b;
assert(c>=a);
return c;
}
}
/**
* A token that can increase its supply by another contract.
*
* This allows uncapped crowdsale by dynamically increasing the supply when money pours in.
* Only mint agents, contracts whitelisted by owner, can mint new tokens.
*
*/
contract MintableToken is StandardTokenExt {
using SafeMathLib for uint;
bool public mintingFinished = false;
/** List of agents that are allowed to create new tokens */
mapping (address => bool) public mintAgents;
event MintingAgentChanged(address addr, bool state);
event Minted(address receiver, uint amount);
/**
* Create new tokens and allocate them to an address..
*
* Only callably by a crowdsale contract (mint agent).
*/
function mint(address receiver, uint amount) onlyMintAgent canMint public {
totalSupply_ = totalSupply_.plus(amount);
balances[receiver] = balances[receiver].plus(amount);
// This will make the mint transaction apper in EtherScan.io
// We can remove this after there is a standardized minting event
Transfer(0, receiver, amount);
}
/**
* Owner can allow a crowdsale contract to mint new tokens.
*/
function setMintAgent(address addr, bool state) onlyOwner canMint public {
mintAgents[addr] = state;
MintingAgentChanged(addr, state);
}
modifier onlyMintAgent() {
// Only crowdsale contracts are allowed to mint new tokens
if(!mintAgents[msg.sender]) {
throw;
}
_;
}
/** Make sure we are not done yet. */
modifier canMint() {
if(mintingFinished) throw;
_;
}
}
/**
* A crowdsaled token.
*
* An ERC-20 token designed specifically for crowdsales with investor protection and further development path.
*
* - The token transfer() is disabled until the crowdsale is over
* - The token contract gives an opt-in upgrade path to a new contract
* - The same token can be part of several crowdsales through approve() mechanism
* - The token can be capped (supply set in the constructor) or uncapped (crowdsale contract can mint new tokens)
*
*/
contract CrowdsaleToken is ReleasableToken, MintableToken, UpgradeableToken {
/** Name and symbol were updated. */
event UpdatedTokenInformation(string newName, string newSymbol);
string public name;
string public symbol;
uint public decimals;
/**
* Construct the token.
*
* This token must be created through a team multisig wallet, so that it is owned by that wallet.
*
* @param _name Token name
* @param _symbol Token symbol - should be all caps
* @param _initialSupply How many tokens we start with
* @param _decimals Number of decimal places
* @param _mintable Are new tokens created over the crowdsale or do we distribute only the initial supply? Note that when the token becomes transferable the minting always ends.
*/
function CrowdsaleToken(string _name, string _symbol, uint _initialSupply, uint _decimals, bool _mintable)
UpgradeableToken(msg.sender) {
// Create any address, can be transferred
// to team multisig via changeOwner(),
// also remember to call setUpgradeMaster()
owner = msg.sender;
name = _name;
symbol = _symbol;
totalSupply_ = _initialSupply;
decimals = _decimals;
// Create initially all balance on the team multisig
balances[owner] = totalSupply_;
if(totalSupply_ > 0) {
Minted(owner, totalSupply_);
}
// No more new supply allowed after the token creation
if(!_mintable) {
mintingFinished = true;
if(totalSupply_ == 0) {
throw; // Cannot create a token without supply and no minting
}
}
}
/**
* When token is released to be transferable, enforce no new tokens can be created.
*/
function releaseTokenTransfer() public onlyReleaseAgent {
mintingFinished = true;
super.releaseTokenTransfer();
}
/**
* Allow upgrade agent functionality kick in only if the crowdsale was success.
*/
function canUpgrade() public constant returns(bool) {
return released && super.canUpgrade();
}
/**
* Owner can update token information here.
*
* It is often useful to conceal the actual token association, until
* the token operations, like central issuance or reissuance have been completed.
*
* This function allows the token owner to rename the token after the operations
* have been completed and then point the audience to use the token contract.
*/
function setTokenInformation(string _name, string _symbol) onlyOwner {
name = _name;
symbol = _symbol;
UpdatedTokenInformation(name, symbol);
}
}
/**
* A crowdsaled token that you can also burn.
*
*/
contract BurnableCrowdsaleToken is BurnableToken, CrowdsaleToken {
function BurnableCrowdsaleToken(string _name, string _symbol, uint _initialSupply, uint _decimals, bool _mintable)
CrowdsaleToken(_name, _symbol, _initialSupply, _decimals, _mintable) {
}
}