Contract Name:
LeveragedToken
Contract Source Code:
File 1 of 1 : LeveragedToken
// File: openzeppelin-solidity/contracts/math/SafeMath.sol
pragma solidity ^0.5.0;
/**
* @dev Wrappers over Solidity's arithmetic operations with added overflow
* checks.
*
* Arithmetic operations in Solidity wrap on overflow. This can easily result
* in bugs, because programmers usually assume that an overflow raises an
* error, which is the standard behavior in high level programming languages.
* `SafeMath` restores this intuition by reverting the transaction when an
* operation overflows.
*
* Using this library instead of the unchecked operations eliminates an entire
* class of bugs, so it's recommended to use it always.
*/
library SafeMath {
/**
* @dev Returns the addition of two unsigned integers, reverting on
* overflow.
*
* Counterpart to Solidity's `+` operator.
*
* Requirements:
* - Addition cannot overflow.
*/
function add(uint256 a, uint256 b) internal pure returns (uint256) {
uint256 c = a + b;
require(c >= a, "SafeMath: addition overflow");
return c;
}
/**
* @dev Returns the subtraction of two unsigned integers, reverting on
* overflow (when the result is negative).
*
* Counterpart to Solidity's `-` operator.
*
* Requirements:
* - Subtraction cannot overflow.
*/
function sub(uint256 a, uint256 b) internal pure returns (uint256) {
require(b <= a, "SafeMath: subtraction overflow");
uint256 c = a - b;
return c;
}
/**
* @dev Returns the multiplication of two unsigned integers, reverting on
* overflow.
*
* Counterpart to Solidity's `*` operator.
*
* Requirements:
* - Multiplication cannot overflow.
*/
function mul(uint256 a, uint256 b) internal pure returns (uint256) {
// Gas optimization: this is cheaper than requiring '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;
}
uint256 c = a * b;
require(c / a == b, "SafeMath: multiplication overflow");
return c;
}
/**
* @dev Returns the integer division of two unsigned integers. Reverts on
* division by zero. The result is rounded towards zero.
*
* Counterpart to Solidity's `/` operator. Note: this function uses a
* `revert` opcode (which leaves remaining gas untouched) while Solidity
* uses an invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
* - The divisor cannot be zero.
*/
function div(uint256 a, uint256 b) internal pure returns (uint256) {
// Solidity only automatically asserts when dividing by 0
require(b > 0, "SafeMath: division by zero");
uint256 c = a / b;
// assert(a == b * c + a % b); // There is no case in which this doesn't hold
return c;
}
/**
* @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
* Reverts when dividing by zero.
*
* Counterpart to Solidity's `%` operator. This function uses a `revert`
* opcode (which leaves remaining gas untouched) while Solidity uses an
* invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
* - The divisor cannot be zero.
*/
function mod(uint256 a, uint256 b) internal pure returns (uint256) {
require(b != 0, "SafeMath: modulo by zero");
return a % b;
}
}
// File: openzeppelin-solidity/contracts/token/ERC20/IERC20.sol
pragma solidity ^0.5.0;
/**
* @dev Interface of the ERC20 standard as defined in the EIP. Does not include
* the optional functions; to access them see `ERC20Detailed`.
*/
interface IERC20 {
/**
* @dev Returns the amount of tokens in existence.
*/
function totalSupply() external view returns (uint256);
/**
* @dev Returns the amount of tokens owned by `account`.
*/
function balanceOf(address account) external view returns (uint256);
/**
* @dev Moves `amount` tokens from the caller's account to `recipient`.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a `Transfer` event.
*/
function transfer(address recipient, uint256 amount) external returns (bool);
/**
* @dev Returns the remaining number of tokens that `spender` will be
* allowed to spend on behalf of `owner` through `transferFrom`. This is
* zero by default.
*
* This value changes when `approve` or `transferFrom` are called.
*/
function allowance(address owner, address spender) external view returns (uint256);
/**
* @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* > 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
*
* Emits an `Approval` event.
*/
function approve(address spender, uint256 amount) external returns (bool);
/**
* @dev Moves `amount` tokens from `sender` to `recipient` using the
* allowance mechanism. `amount` is then deducted from the caller's
* allowance.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a `Transfer` event.
*/
function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);
/**
* @dev Emitted when `value` tokens are moved from one account (`from`) to
* another (`to`).
*
* Note that `value` may be zero.
*/
event Transfer(address indexed from, address indexed to, uint256 value);
/**
* @dev Emitted when the allowance of a `spender` for an `owner` is set by
* a call to `approve`. `value` is the new allowance.
*/
event Approval(address indexed owner, address indexed spender, uint256 value);
}
// File: openzeppelin-solidity/contracts/token/ERC20/ERC20Detailed.sol
pragma solidity ^0.5.0;
/**
* @dev Optional functions from the ERC20 standard.
*/
contract ERC20Detailed is IERC20 {
string private _name;
string private _symbol;
uint8 private _decimals;
/**
* @dev Sets the values for `name`, `symbol`, and `decimals`. All three of
* these values are immutable: they can only be set once during
* construction.
*/
constructor (string memory name, string memory symbol, uint8 decimals) public {
_name = name;
_symbol = symbol;
_decimals = decimals;
}
/**
* @dev Returns the name of the token.
*/
function name() public view returns (string memory) {
return _name;
}
/**
* @dev Returns the symbol of the token, usually a shorter version of the
* name.
*/
function symbol() public view returns (string memory) {
return _symbol;
}
/**
* @dev Returns the number of decimals used to get its user representation.
* For example, if `decimals` equals `2`, a balance of `505` tokens should
* be displayed to a user as `5,05` (`505 / 10 ** 2`).
*
* Tokens usually opt for a value of 18, imitating the relationship between
* Ether and Wei.
*
* > Note that this information is only used for _display_ purposes: it in
* no way affects any of the arithmetic of the contract, including
* `IERC20.balanceOf` and `IERC20.transfer`.
*/
function decimals() public view returns (uint8) {
return _decimals;
}
}
// File: openzeppelin-solidity/contracts/token/ERC20/ERC20.sol
pragma solidity ^0.5.0;
/**
* @dev Implementation of the `IERC20` interface.
*
* This implementation is agnostic to the way tokens are created. This means
* that a supply mechanism has to be added in a derived contract using `_mint`.
* For a generic mechanism see `ERC20Mintable`.
*
* *For a detailed writeup see our guide [How to implement supply
* mechanisms](https://forum.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226).*
*
* We have followed general OpenZeppelin guidelines: functions revert instead
* of returning `false` on failure. This behavior is nonetheless conventional
* and does not conflict with the expectations of ERC20 applications.
*
* Additionally, an `Approval` event is emitted on calls to `transferFrom`.
* This allows applications to reconstruct the allowance for all accounts just
* by listening to said events. Other implementations of the EIP may not emit
* these events, as it isn't required by the specification.
*
* Finally, the non-standard `decreaseAllowance` and `increaseAllowance`
* functions have been added to mitigate the well-known issues around setting
* allowances. See `IERC20.approve`.
*/
contract ERC20 is IERC20 {
using SafeMath for uint256;
mapping (address => uint256) private _balances;
mapping (address => mapping (address => uint256)) private _allowances;
uint256 private _totalSupply;
/**
* @dev See `IERC20.totalSupply`.
*/
function totalSupply() public view returns (uint256) {
return _totalSupply;
}
/**
* @dev See `IERC20.balanceOf`.
*/
function balanceOf(address account) public view returns (uint256) {
return _balances[account];
}
/**
* @dev See `IERC20.transfer`.
*
* Requirements:
*
* - `recipient` cannot be the zero address.
* - the caller must have a balance of at least `amount`.
*/
function transfer(address recipient, uint256 amount) public returns (bool) {
_transfer(msg.sender, recipient, amount);
return true;
}
/**
* @dev See `IERC20.allowance`.
*/
function allowance(address owner, address spender) public view returns (uint256) {
return _allowances[owner][spender];
}
/**
* @dev See `IERC20.approve`.
*
* Requirements:
*
* - `spender` cannot be the zero address.
*/
function approve(address spender, uint256 value) public returns (bool) {
_approve(msg.sender, spender, value);
return true;
}
/**
* @dev See `IERC20.transferFrom`.
*
* Emits an `Approval` event indicating the updated allowance. This is not
* required by the EIP. See the note at the beginning of `ERC20`;
*
* Requirements:
* - `sender` and `recipient` cannot be the zero address.
* - `sender` must have a balance of at least `value`.
* - the caller must have allowance for `sender`'s tokens of at least
* `amount`.
*/
function transferFrom(address sender, address recipient, uint256 amount) public returns (bool) {
_transfer(sender, recipient, amount);
_approve(sender, msg.sender, _allowances[sender][msg.sender].sub(amount));
return true;
}
/**
* @dev Atomically increases the allowance granted to `spender` by the caller.
*
* This is an alternative to `approve` that can be used as a mitigation for
* problems described in `IERC20.approve`.
*
* Emits an `Approval` event indicating the updated allowance.
*
* Requirements:
*
* - `spender` cannot be the zero address.
*/
function increaseAllowance(address spender, uint256 addedValue) public returns (bool) {
_approve(msg.sender, spender, _allowances[msg.sender][spender].add(addedValue));
return true;
}
/**
* @dev Atomically decreases the allowance granted to `spender` by the caller.
*
* This is an alternative to `approve` that can be used as a mitigation for
* problems described in `IERC20.approve`.
*
* Emits an `Approval` event indicating the updated allowance.
*
* Requirements:
*
* - `spender` cannot be the zero address.
* - `spender` must have allowance for the caller of at least
* `subtractedValue`.
*/
function decreaseAllowance(address spender, uint256 subtractedValue) public returns (bool) {
_approve(msg.sender, spender, _allowances[msg.sender][spender].sub(subtractedValue));
return true;
}
/**
* @dev Moves tokens `amount` from `sender` to `recipient`.
*
* This is internal function is equivalent to `transfer`, and can be used to
* e.g. implement automatic token fees, slashing mechanisms, etc.
*
* Emits a `Transfer` event.
*
* Requirements:
*
* - `sender` cannot be the zero address.
* - `recipient` cannot be the zero address.
* - `sender` must have a balance of at least `amount`.
*/
function _transfer(address sender, address recipient, uint256 amount) internal {
require(sender != address(0), "ERC20: transfer from the zero address");
require(recipient != address(0), "ERC20: transfer to the zero address");
_balances[sender] = _balances[sender].sub(amount);
_balances[recipient] = _balances[recipient].add(amount);
emit Transfer(sender, recipient, amount);
}
/** @dev Creates `amount` tokens and assigns them to `account`, increasing
* the total supply.
*
* Emits a `Transfer` event with `from` set to the zero address.
*
* Requirements
*
* - `to` cannot be the zero address.
*/
function _mint(address account, uint256 amount) internal {
require(account != address(0), "ERC20: mint to the zero address");
_totalSupply = _totalSupply.add(amount);
_balances[account] = _balances[account].add(amount);
emit Transfer(address(0), account, amount);
}
/**
* @dev Destoys `amount` tokens from `account`, reducing the
* total supply.
*
* Emits a `Transfer` event with `to` set to the zero address.
*
* Requirements
*
* - `account` cannot be the zero address.
* - `account` must have at least `amount` tokens.
*/
function _burn(address account, uint256 value) internal {
require(account != address(0), "ERC20: burn from the zero address");
_totalSupply = _totalSupply.sub(value);
_balances[account] = _balances[account].sub(value);
emit Transfer(account, address(0), value);
}
/**
* @dev Sets `amount` as the allowance of `spender` over the `owner`s tokens.
*
* This is internal function is equivalent to `approve`, and can be used to
* e.g. set automatic allowances for certain subsystems, etc.
*
* Emits an `Approval` event.
*
* Requirements:
*
* - `owner` cannot be the zero address.
* - `spender` cannot be the zero address.
*/
function _approve(address owner, address spender, uint256 value) internal {
require(owner != address(0), "ERC20: approve from the zero address");
require(spender != address(0), "ERC20: approve to the zero address");
_allowances[owner][spender] = value;
emit Approval(owner, spender, value);
}
/**
* @dev Destoys `amount` tokens from `account`.`amount` is then deducted
* from the caller's allowance.
*
* See `_burn` and `_approve`.
*/
function _burnFrom(address account, uint256 amount) internal {
_burn(account, amount);
_approve(account, msg.sender, _allowances[account][msg.sender].sub(amount));
}
}
// File: openzeppelin-solidity/contracts/access/Roles.sol
pragma solidity ^0.5.0;
/**
* @title Roles
* @dev Library for managing addresses assigned to a Role.
*/
library Roles {
struct Role {
mapping (address => bool) bearer;
}
/**
* @dev Give an account access to this role.
*/
function add(Role storage role, address account) internal {
require(!has(role, account), "Roles: account already has role");
role.bearer[account] = true;
}
/**
* @dev Remove an account's access to this role.
*/
function remove(Role storage role, address account) internal {
require(has(role, account), "Roles: account does not have role");
role.bearer[account] = false;
}
/**
* @dev Check if an account has this role.
* @return bool
*/
function has(Role storage role, address account) internal view returns (bool) {
require(account != address(0), "Roles: account is the zero address");
return role.bearer[account];
}
}
// File: openzeppelin-solidity/contracts/access/roles/PauserRole.sol
pragma solidity ^0.5.0;
contract PauserRole {
using Roles for Roles.Role;
event PauserAdded(address indexed account);
event PauserRemoved(address indexed account);
Roles.Role private _pausers;
constructor () internal {
_addPauser(msg.sender);
}
modifier onlyPauser() {
require(isPauser(msg.sender), "PauserRole: caller does not have the Pauser role");
_;
}
function isPauser(address account) public view returns (bool) {
return _pausers.has(account);
}
function addPauser(address account) public onlyPauser {
_addPauser(account);
}
function renouncePauser() public {
_removePauser(msg.sender);
}
function _addPauser(address account) internal {
_pausers.add(account);
emit PauserAdded(account);
}
function _removePauser(address account) internal {
_pausers.remove(account);
emit PauserRemoved(account);
}
}
// File: openzeppelin-solidity/contracts/lifecycle/Pausable.sol
pragma solidity ^0.5.0;
/**
* @dev Contract module which allows children to implement an emergency stop
* mechanism that can be triggered by an authorized account.
*
* This module is used through inheritance. It will make available the
* modifiers `whenNotPaused` and `whenPaused`, which can be applied to
* the functions of your contract. Note that they will not be pausable by
* simply including this module, only once the modifiers are put in place.
*/
contract Pausable is PauserRole {
/**
* @dev Emitted when the pause is triggered by a pauser (`account`).
*/
event Paused(address account);
/**
* @dev Emitted when the pause is lifted by a pauser (`account`).
*/
event Unpaused(address account);
bool private _paused;
/**
* @dev Initializes the contract in unpaused state. Assigns the Pauser role
* to the deployer.
*/
constructor () internal {
_paused = false;
}
/**
* @dev Returns true if the contract is paused, and false otherwise.
*/
function paused() public view returns (bool) {
return _paused;
}
/**
* @dev Modifier to make a function callable only when the contract is not paused.
*/
modifier whenNotPaused() {
require(!_paused, "Pausable: paused");
_;
}
/**
* @dev Modifier to make a function callable only when the contract is paused.
*/
modifier whenPaused() {
require(_paused, "Pausable: not paused");
_;
}
/**
* @dev Called by a pauser to pause, triggers stopped state.
*/
function pause() public onlyPauser whenNotPaused {
_paused = true;
emit Paused(msg.sender);
}
/**
* @dev Called by a pauser to unpause, returns to normal state.
*/
function unpause() public onlyPauser whenPaused {
_paused = false;
emit Unpaused(msg.sender);
}
}
// File: openzeppelin-solidity/contracts/token/ERC20/ERC20Pausable.sol
pragma solidity ^0.5.0;
/**
* @title Pausable token
* @dev ERC20 modified with pausable transfers.
*/
contract ERC20Pausable is ERC20, 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 increaseAllowance(address spender, uint addedValue) public whenNotPaused returns (bool) {
return super.increaseAllowance(spender, addedValue);
}
function decreaseAllowance(address spender, uint subtractedValue) public whenNotPaused returns (bool) {
return super.decreaseAllowance(spender, subtractedValue);
}
}
// File: openzeppelin-solidity/contracts/access/roles/MinterRole.sol
pragma solidity ^0.5.0;
contract MinterRole {
using Roles for Roles.Role;
event MinterAdded(address indexed account);
event MinterRemoved(address indexed account);
Roles.Role private _minters;
constructor () internal {
_addMinter(msg.sender);
}
modifier onlyMinter() {
require(isMinter(msg.sender), "MinterRole: caller does not have the Minter role");
_;
}
function isMinter(address account) public view returns (bool) {
return _minters.has(account);
}
function addMinter(address account) public onlyMinter {
_addMinter(account);
}
function renounceMinter() public {
_removeMinter(msg.sender);
}
function _addMinter(address account) internal {
_minters.add(account);
emit MinterAdded(account);
}
function _removeMinter(address account) internal {
_minters.remove(account);
emit MinterRemoved(account);
}
}
// File: openzeppelin-solidity/contracts/token/ERC20/ERC20Mintable.sol
pragma solidity ^0.5.0;
/**
* @dev Extension of `ERC20` that adds a set of accounts with the `MinterRole`,
* which have permission to mint (create) new tokens as they see fit.
*
* At construction, the deployer of the contract is the only minter.
*/
contract ERC20Mintable is ERC20, MinterRole {
/**
* @dev See `ERC20._mint`.
*
* Requirements:
*
* - the caller must have the `MinterRole`.
*/
function mint(address account, uint256 amount) public onlyMinter returns (bool) {
_mint(account, amount);
return true;
}
}
// File: openzeppelin-solidity/contracts/ownership/Ownable.sol
pragma solidity ^0.5.0;
/**
* @dev Contract module which provides a basic access control mechanism, where
* there is an account (an owner) that can be granted exclusive access to
* specific functions.
*
* This module is used through inheritance. It will make available the modifier
* `onlyOwner`, which can be aplied to your functions to restrict their use to
* the owner.
*/
contract Ownable {
address private _owner;
event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
/**
* @dev Initializes the contract setting the deployer as the initial owner.
*/
constructor () internal {
_owner = msg.sender;
emit OwnershipTransferred(address(0), _owner);
}
/**
* @dev Returns the address of the current owner.
*/
function owner() public view returns (address) {
return _owner;
}
/**
* @dev Throws if called by any account other than the owner.
*/
modifier onlyOwner() {
require(isOwner(), "Ownable: caller is not the owner");
_;
}
/**
* @dev Returns true if the caller is the current owner.
*/
function isOwner() public view returns (bool) {
return msg.sender == _owner;
}
/**
* @dev Leaves the contract without owner. It will not be possible to call
* `onlyOwner` functions anymore. Can only be called by the current owner.
*
* > Note: Renouncing ownership will leave the contract without an owner,
* thereby removing any functionality that is only available to the owner.
*/
function renounceOwnership() public onlyOwner {
emit OwnershipTransferred(_owner, address(0));
_owner = address(0);
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`).
* Can only be called by the current owner.
*/
function transferOwnership(address newOwner) public onlyOwner {
_transferOwnership(newOwner);
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`).
*/
function _transferOwnership(address newOwner) internal {
require(newOwner != address(0), "Ownable: new owner is the zero address");
emit OwnershipTransferred(_owner, newOwner);
_owner = newOwner;
}
}
// File: contracts/whitelist/IWhitelist.sol
pragma solidity ^0.5.0;
// Interface to be implemented by the Whitelist contract.
contract IWhitelist {
function isWhitelisted(address account) public view returns (bool);
}
// File: contracts/token/BurnerRole.sol
pragma solidity ^0.5.0;
contract BurnerRole {
using Roles for Roles.Role;
event BurnerAdded(address indexed account);
event BurnerRemoved(address indexed account);
Roles.Role private _burners;
constructor () internal {
_addBurner(msg.sender);
}
modifier onlyBurner() {
require(isBurner(msg.sender));
_;
}
function isBurner(address account) public view returns (bool) {
return _burners.has(account);
}
function addBurner(address account) public onlyBurner {
_addBurner(account);
}
function renounceBurner() public {
_removeBurner(msg.sender);
}
function _addBurner(address account) internal {
_burners.add(account);
emit BurnerAdded(account);
}
function _removeBurner(address account) internal {
_burners.remove(account);
emit BurnerRemoved(account);
}
}
// File: contracts/token/ERC20Burnable.sol
pragma solidity ^0.5.0;
// Only allow accounts with the burner role to burn tokens.
contract ERC20Burnable is ERC20, BurnerRole {
function burn(uint256 value) public onlyBurner() {
_burn(msg.sender, value);
}
function burnFrom(address from, uint256 value) public onlyBurner() {
_burnFrom(from, value);
}
}
// File: contracts/token/ERC20Whitelistable.sol
pragma solidity ^0.5.0;
// Disallow transfers of the token to or from blacklisted accounts.
contract ERC20Whitelistable is ERC20Mintable, ERC20Burnable, Ownable {
event WhitelistChanged(IWhitelist indexed account);
IWhitelist public whitelist;
function setWhitelist(IWhitelist _whitelist) public onlyOwner {
whitelist = _whitelist;
emit WhitelistChanged(_whitelist);
}
modifier onlyWhitelisted(address account) {
require(isWhitelisted(account));
_;
}
modifier notWhitelisted(address account) {
require(!isWhitelisted(account));
_;
}
// Returns true if the account is allowed to send and receive tokens.
function isWhitelisted(address account) public view returns (bool) {
return whitelist.isWhitelisted(account);
}
function transfer(address to, uint256 value)
public
onlyWhitelisted(msg.sender)
onlyWhitelisted(to)
returns (bool)
{
return super.transfer(to, value);
}
function transferFrom(address from, address to, uint256 value)
public
onlyWhitelisted(from)
onlyWhitelisted(to)
returns (bool)
{
return super.transferFrom(from, to, value);
}
function mint(address to, uint256 value) public onlyWhitelisted(to) returns (bool) {
return super.mint(to, value);
}
// Destroy the tokens held by a blacklisted account.
function burnBlacklisted(address from, uint256 value)
public
onlyBurner()
notWhitelisted(from)
{
_burn(from, value);
}
}
// File: contracts/utils/CanReclaimEther.sol
pragma solidity ^0.5.0;
// Ether should not be sent to this contract. If any ether is accidentally sent to this
// contract, allow the contract owner to recover it.
// Copied from https://github.com/OpenZeppelin/openzeppelin-solidity/blob/2441fd7d17bffa1944f6f539b2cddd6d19997a31/contracts/ownership/HasNoEther.sol
contract CanReclaimEther is Ownable {
function reclaimEther() external onlyOwner {
msg.sender.transfer(address(this).balance);
}
}
// File: openzeppelin-solidity/contracts/utils/Address.sol
pragma solidity ^0.5.0;
/**
* @dev Collection of functions related to the address type,
*/
library Address {
/**
* @dev Returns true if `account` is a contract.
*
* This test is non-exhaustive, and there may be false-negatives: during the
* execution of a contract's constructor, its address will be reported as
* not containing a contract.
*
* > It is unsafe to assume that an address for which this function returns
* false is an externally-owned account (EOA) and not a contract.
*/
function isContract(address account) internal view returns (bool) {
// This method relies in extcodesize, which returns 0 for contracts in
// construction, since the code is only stored at the end of the
// constructor execution.
uint256 size;
// solhint-disable-next-line no-inline-assembly
assembly { size := extcodesize(account) }
return size > 0;
}
}
// File: openzeppelin-solidity/contracts/token/ERC20/SafeERC20.sol
pragma solidity ^0.5.0;
/**
* @title SafeERC20
* @dev Wrappers around ERC20 operations that throw on failure (when the token
* contract returns false). Tokens that return no value (and instead revert or
* throw on failure) are also supported, non-reverting calls are assumed to be
* successful.
* 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 {
using SafeMath for uint256;
using Address for address;
function safeTransfer(IERC20 token, address to, uint256 value) internal {
callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
}
function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal {
callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
}
function safeApprove(IERC20 token, address spender, uint256 value) internal {
// safeApprove should only be called when setting an initial allowance,
// or when resetting it to zero. To increase and decrease it, use
// 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
// solhint-disable-next-line max-line-length
require((value == 0) || (token.allowance(address(this), spender) == 0),
"SafeERC20: approve from non-zero to non-zero allowance"
);
callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
}
function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
uint256 newAllowance = token.allowance(address(this), spender).add(value);
callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
}
function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal {
uint256 newAllowance = token.allowance(address(this), spender).sub(value);
callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
}
/**
* @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
* on the return value: the return value is optional (but if data is returned, it must not be false).
* @param token The token targeted by the call.
* @param data The call data (encoded using abi.encode or one of its variants).
*/
function callOptionalReturn(IERC20 token, bytes memory data) private {
// We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
// we're implementing it ourselves.
// A Solidity high level call has three parts:
// 1. The target address is checked to verify it contains contract code
// 2. The call itself is made, and success asserted
// 3. The return value is decoded, which in turn checks the size of the returned data.
// solhint-disable-next-line max-line-length
require(address(token).isContract(), "SafeERC20: call to non-contract");
// solhint-disable-next-line avoid-low-level-calls
(bool success, bytes memory returndata) = address(token).call(data);
require(success, "SafeERC20: low-level call failed");
if (returndata.length > 0) { // Return data is optional
// solhint-disable-next-line max-line-length
require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
}
}
}
// File: contracts/utils/CanReclaimToken.sol
pragma solidity ^0.5.0;
// Tokens should not be sent to this contract. If any tokens are accidentally sent to
// this contract, allow the contract owner to recover them.
// Copied from https://github.com/OpenZeppelin/openzeppelin-solidity/blob/6c4c8989b399510a66d8b98ad75a0979482436d2/contracts/ownership/CanReclaimToken.sol
contract CanReclaimToken is Ownable {
using SafeERC20 for IERC20;
function reclaimToken(IERC20 token) external onlyOwner {
uint256 balance = token.balanceOf(address(this));
token.safeTransfer(owner(), balance);
}
}
// File: contracts/token/LeveragedToken.sol
pragma solidity ^0.5.0;
contract LeveragedToken is
ERC20Detailed,
ERC20Pausable,
ERC20Mintable,
ERC20Burnable,
ERC20Whitelistable,
CanReclaimEther,
CanReclaimToken
{
string public underlying;
int8 public leverage;
constructor(string memory name, string memory symbol, string memory _underlying, int8 _leverage)
ERC20Detailed(name, symbol, 18)
public
{
underlying = _underlying;
leverage = _leverage;
}
}