Contract Source Code:
File 1 of 1 : WBTC
pragma solidity 0.4.24;
// File: openzeppelin-solidity/contracts/token/ERC20/ERC20Basic.sol
/**
* @title ERC20Basic
* @dev Simpler version of ERC20 interface
* 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);
}
// File: openzeppelin-solidity/contracts/math/SafeMath.sol
/**
* @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 c) {
// Gas optimization: this is cheaper than asserting 'a' not being zero, but the
// benefit is lost if 'b' is also tested.
// See: https://github.com/OpenZeppelin/openzeppelin-solidity/pull/522
if (_a == 0) {
return 0;
}
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 c) {
c = _a + _b;
assert(c >= _a);
return c;
}
}
// File: openzeppelin-solidity/contracts/token/ERC20/BasicToken.sol
/**
* @title Basic token
* @dev Basic version of StandardToken, with no allowances.
*/
contract BasicToken is ERC20Basic {
using SafeMath for uint256;
mapping(address => uint256) internal balances;
uint256 internal 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(_value <= balances[msg.sender]);
require(_to != address(0));
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) {
return balances[_owner];
}
}
// File: openzeppelin-solidity/contracts/token/ERC20/ERC20.sol
/**
* @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
);
}
// File: openzeppelin-solidity/contracts/token/ERC20/StandardToken.sol
/**
* @title Standard ERC20 token
*
* @dev Implementation of the basic standard token.
* https://github.com/ethereum/EIPs/issues/20
* 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(_value <= balances[_from]);
require(_value <= allowed[_from][msg.sender]);
require(_to != address(0));
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,
uint256 _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,
uint256 _subtractedValue
)
public
returns (bool)
{
uint256 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;
}
}
// File: openzeppelin-solidity/contracts/token/ERC20/DetailedERC20.sol
/**
* @title DetailedERC20 token
* @dev The decimals are only for visualization purposes.
* All the operations are done using the smallest and indivisible token unit,
* just as on Ethereum all the operations are done in wei.
*/
contract DetailedERC20 is ERC20 {
string public name;
string public symbol;
uint8 public decimals;
constructor(string _name, string _symbol, uint8 _decimals) public {
name = _name;
symbol = _symbol;
decimals = _decimals;
}
}
// File: openzeppelin-solidity/contracts/ownership/Ownable.sol
/**
* @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 relinquish control of the contract.
* @notice Renouncing to ownership will leave the contract without an owner.
* It will not be possible to call the functions with the `onlyOwner`
* modifier anymore.
*/
function renounceOwnership() public onlyOwner {
emit OwnershipRenounced(owner);
owner = address(0);
}
/**
* @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 {
_transferOwnership(_newOwner);
}
/**
* @dev Transfers control of the contract to a newOwner.
* @param _newOwner The address to transfer ownership to.
*/
function _transferOwnership(address _newOwner) internal {
require(_newOwner != address(0));
emit OwnershipTransferred(owner, _newOwner);
owner = _newOwner;
}
}
// File: openzeppelin-solidity/contracts/token/ERC20/MintableToken.sol
/**
* @title Mintable token
* @dev Simple ERC20 Token example, with mintable token creation
* 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);
_;
}
modifier hasMintPermission() {
require(msg.sender == owner);
_;
}
/**
* @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
hasMintPermission
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;
}
}
// File: openzeppelin-solidity/contracts/token/ERC20/BurnableToken.sol
/**
* @title Burnable Token
* @dev Token that can be irreversibly burned (destroyed).
*/
contract BurnableToken is BasicToken {
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);
}
}
// File: openzeppelin-solidity/contracts/lifecycle/Pausable.sol
/**
* @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();
}
}
// File: openzeppelin-solidity/contracts/token/ERC20/PausableToken.sol
/**
* @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);
}
}
// File: openzeppelin-solidity/contracts/ownership/Claimable.sol
/**
* @title Claimable
* @dev Extension for the Ownable contract, where the ownership needs to be claimed.
* This allows the new owner to accept the transfer.
*/
contract Claimable is Ownable {
address public pendingOwner;
/**
* @dev Modifier throws if called by any account other than the pendingOwner.
*/
modifier onlyPendingOwner() {
require(msg.sender == pendingOwner);
_;
}
/**
* @dev Allows the current owner to set the pendingOwner address.
* @param newOwner The address to transfer ownership to.
*/
function transferOwnership(address newOwner) public onlyOwner {
pendingOwner = newOwner;
}
/**
* @dev Allows the pendingOwner address to finalize the transfer.
*/
function claimOwnership() public onlyPendingOwner {
emit OwnershipTransferred(owner, pendingOwner);
owner = pendingOwner;
pendingOwner = address(0);
}
}
// File: openzeppelin-solidity/contracts/token/ERC20/SafeERC20.sol
/**
* @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));
}
}
// File: openzeppelin-solidity/contracts/ownership/CanReclaimToken.sol
/**
* @title Contracts that should be able to recover tokens
* @author SylTi
* @dev This allow a contract to recover any ERC20 token received in a contract by transferring the balance to the contract owner.
* This will prevent any accidental loss of tokens.
*/
contract CanReclaimToken is Ownable {
using SafeERC20 for ERC20Basic;
/**
* @dev Reclaim all ERC20Basic compatible tokens
* @param _token ERC20Basic The address of the token contract
*/
function reclaimToken(ERC20Basic _token) external onlyOwner {
uint256 balance = _token.balanceOf(this);
_token.safeTransfer(owner, balance);
}
}
// File: contracts/utils/OwnableContract.sol
// empty block is used as this contract just inherits others.
contract OwnableContract is CanReclaimToken, Claimable { } /* solhint-disable-line no-empty-blocks */
// File: contracts/token/WBTC.sol
contract WBTC is StandardToken, DetailedERC20("Wrapped BTC", "WBTC", 8),
MintableToken, BurnableToken, PausableToken, OwnableContract {
function burn(uint value) public onlyOwner {
super.burn(value);
}
function finishMinting() public onlyOwner returns (bool) {
return false;
}
function renounceOwnership() public onlyOwner {
revert("renouncing ownership is blocked");
}
}