pragmasolidity ^0.5.0;import'./ERC20.sol';
import'./ERC20Detailed.sol';
import'./ERC20Pausable.sol';
contractDQCisERC20, ERC20Detailed, ERC20Pausable{
constructor(stringmemory name, stringmemory symbol, uint8 decimals,uint256 _totalSupply) ERC20Pausable() ERC20Detailed(name, symbol, decimals) ERC20() public{
require(_totalSupply >0);
_mint(msg.sender, _totalSupply *10**uint256(decimals));
}
/**
* @dev Burns a specific amount of tokens.
* @param value The amount of token to be burned.
*/functionburn(uint256 value) publicwhenNotPaused{
require(!isLock(msg.sender));
_burn(msg.sender, value);
}
/**
* @dev Freeze a specific amount of tokens.
* @param value The amount of token to be Freeze.
*/functionfreeze(uint256 value) publicwhenNotPaused{
require(!isLock(msg.sender));
_freeze(value);
}
/**
* @dev unFreeze a specific amount of tokens.
* @param value The amount of token to be unFreeze.
*/functionunfreeze(uint256 value) publicwhenNotPaused{
require(!isLock(msg.sender));
_unfreeze(value);
}
}
Contract Source Code
File 2 of 10: ERC20.sol
pragmasolidity ^0.5.0;import'./ERC20Interface.sol';
import'./SafeMath.sol';
/**
* @title Standard ERC20 token
* @dev Implementation of the basic standard token.
*/contractERC20isIERC20{
usingSafeMathforuint256;
mapping (address=>uint256) private _balances;
mapping (address=>mapping (address=>uint256)) private _allowed;
mapping (address=>uint256) private _freezeOf;
uint256private _totalSupply;
/**
* @dev Total number of tokens in existence.
*/functiontotalSupply() publicviewreturns (uint256) {
return _totalSupply;
}
/**
* @dev Gets the balance of the specified address.
* @param tokenOwner The address to query the balance of.
* @return A uint256 representing the amount owned by the passed address.
*/functionbalanceOf(address tokenOwner) publicviewreturns (uint256 balance) {
return _balances[tokenOwner];
}
/**
* @dev Gets the balance of the specified freeze address.
* @param tokenOwner The address to query the balance of.
* @return A uint256 representing the amount owned by the freeze address.
*/functionfreezeOf(address tokenOwner) publicviewreturns (uint256) {
return _freezeOf[tokenOwner];
}
/**
* @dev Function to check the amount of tokens that an owner allowed to a spender.
* @param tokenOwner 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.
*/functionallowance(address tokenOwner, address spender) publicviewreturns (uint256) {
return _allowed[tokenOwner][spender];
}
/**
* @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.
*/functionapprove(address spender, uint256 value) publicreturns (bool success) {
_approve(msg.sender, spender, value);
returntrue;
}
/**
* @dev Approve an address to spend another addresses' tokens.
* @param tokenOwner The address that owns the tokens.
* @param spender The address that will spend the tokens.
* @param value The number of tokens that can be spent.
*/function_approve(address tokenOwner, address spender, uint256 value) internal{
require(tokenOwner !=address(0), "ERC20: approve from the zero address");
require(spender !=address(0), "ERC20: approve to the zero address");
_allowed[tokenOwner][spender] = value;
emit Approval(tokenOwner, spender, value);
}
/**
* @dev Transfer token to a specified address.
* @param to The address to transfer to.
* @param value The amount to be transferred.
*/functiontransfer(address to, uint256 value) publicreturns (bool) {
_transfer(msg.sender, to, value);
returntrue;
}
/**
* @dev Transfer tokens from one address to another.
* Note that while this function emits an Approval event, this is not required as per the specification,
* and other compliant implementations may not emit the event.
* @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
*/functiontransferFrom(addressfrom, address to, uint256 value) publicreturns (bool success) {
_transfer(from, to, value);
_approve(from, msg.sender, _allowed[from][msg.sender].sub(value));
returntrue;
}
/**
* @dev Transfer token for a specified addresses.
* @param from The address to transfer from.
* @param to The address to transfer to.
* @param value The amount to be transferred.
*/function_transfer(addressfrom, address to, uint256 value) internal{
require(from!=address(0), "ERC20: transfer from the zero address");
require(to !=address(0), "ERC20: transfer to the zero address");
_balances[from] = _balances[from].sub(value);
_balances[to] = _balances[to].add(value);
emit Transfer(from, to, value);
}
/**
* @dev Increase the amount of tokens that an owner allowed to a spender.
* approve should be called when _allowed[msg.sender][spender] == 0.
* To increment allowed value is better to use this function to avoid 2 calls (and wait until the first transaction is mined)
* Emits an Approval event.
* @param spender The address which will spend the funds.
* @param addedValue The amount of tokens to increase the allowance by.
*/functionincreaseAllowance(address spender, uint256 addedValue) publicreturns (bool success) {
_approve(msg.sender, spender, _allowed[msg.sender][spender].add(addedValue));
returntrue;
}
/**
* @dev Decrease the amount of tokens that an owner allowed to a spender.
* approve should be called when _allowed[msg.sender][spender] == 0.
* To decrement allowed value is better to use this function to avoid 2 calls (and wait until the first transaction is mined)
* Emits an Approval event.
* @param spender The address which will spend the funds.
* @param subtractedValue The amount of tokens to decrease the allowance by.
*/functiondecreaseAllowance(address spender, uint256 subtractedValue) publicreturns (bool success) {
_approve(msg.sender, spender, _allowed[msg.sender][spender].sub(subtractedValue));
returntrue;
}
/**
* @dev Internal function that mints an amount of the token and assigns it to an account.
* This encapsulates the modification of balances such that the
* Emits a Transfer event.
* @param account The account that will receive the created tokens.
* @param value The amount that will be created.
*/function_mint(address account, uint256 value) internal{
require(account !=address(0), "ERC20: mint to the zero address");
_totalSupply = _totalSupply.add(value);
_balances[account] = _balances[account].add(value);
emit Transfer(address(0), account, value);
}
/**
* @dev Internal function that burns an amount of the token of a given account.
* @param account The account whose tokens will be burnt.
* @param value The amount that will be burnt.
*/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);
}
function_freeze(uint256 value) internal{
require(_balances[msg.sender] >= value,"ERC20: balance is not enough");
require(value >0,"ERC20: value must be greater than 0");
_balances[msg.sender] = _balances[msg.sender].sub(value);
_freezeOf[msg.sender] = _freezeOf[msg.sender].add(value);
emit Freeze(msg.sender, value);
}
function_unfreeze(uint256 value) internal{
require(_freezeOf[msg.sender] >= value,"ERC20: balance is not enough");
require(value >0,"ERC20: value must be greater than 0");
_freezeOf[msg.sender] = _freezeOf[msg.sender].sub(value);
_balances[msg.sender] = _balances[msg.sender].add(value);
emit Unfreeze(msg.sender, value);
}
}
Contract Source Code
File 3 of 10: ERC20Detailed.sol
pragmasolidity ^0.5.0;import'./ERC20Interface.sol';
/**
* @title ERC20Detailed 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.
*/contractERC20DetailedisIERC20{
stringprivate _name;
stringprivate _symbol;
uint8private _decimals;
constructor (stringmemory name, stringmemory symbol, uint8 decimals) public{
_name = name;
_symbol = symbol;
_decimals = decimals;
}
/**
* @return the name of the token.
*/functionname() publicviewreturns (stringmemory) {
return _name;
}
/**
* @return the symbol of the token.
*/functionsymbol() publicviewreturns (stringmemory) {
return _symbol;
}
/**
* @return the number of decimals of the token.
*/functiondecimals() publicviewreturns (uint8) {
return _decimals;
}
}
pragmasolidity ^0.5.0;import'./PauserRole.sol';
/**
* @title Lockable
* @dev Base contract which allows children to implement an emergency stop mechanism.
*/contractLockableisPauserRole{
mapping (address=>bool) private lockers;
eventLockAccount(address account, bool islock);
/**
* @dev Check if the account is locked.
* @param account specific account address.
*/functionisLock(address account) publicviewreturns (bool) {
return lockers[account];
}
/**
* @dev Lock or thaw account address
* @param account specific account address.
* @param islock true lock, false thaw.
*/functionlock(address account, bool islock) publiconlyPauser{
lockers[account] = islock;
emit LockAccount(account, islock);
}
}
Contract Source Code
File 7 of 10: Pausable.sol
pragmasolidity ^0.5.0;import'./PauserRole.sol';
/**
* @title Pausable
* @dev Base contract which allows children to implement an emergency stop mechanism.
*/contractPausableisPauserRole{
eventPaused(address account);
eventUnpaused(address account);
boolprivate _paused;
constructor () internal{
_paused =false;
}
/**
* @return True if the contract is paused, false otherwise.
*/functionpaused() publicviewreturns (bool) {
return _paused;
}
/**
* @dev Modifier to make a function callable only when the contract is not paused.
*/modifierwhenNotPaused() {
require(!_paused);
_;
}
/**
* @dev Modifier to make a function callable only when the contract is paused.
*/modifierwhenPaused() {
require(_paused);
_;
}
/**
* @dev Called by a pauser to pause, triggers stopped state.
*/functionpause() publiconlyPauserwhenNotPaused{
_paused =true;
emit Paused(msg.sender);
}
/**
* @dev Called by a pauser to unpause, returns to normal state.
*/functionunpause() publiconlyPauserwhenPaused{
_paused =false;
emit Unpaused(msg.sender);
}
}
pragmasolidity ^0.5.0;/**
* @title Roles
* @dev Library for managing addresses assigned to a Role.
*/libraryRoles{
structRole {
mapping (address=>bool) bearer;
}
/**
* @dev Give an account access to this role.
*/functionadd(Role storage role, address account) internal{
require(!has(role, account));
role.bearer[account] =true;
}
/**
* @dev Remove an account's access to this role.
*/functionremove(Role storage role, address account) internal{
require(has(role, account));
role.bearer[account] =false;
}
/**
* @dev Check if an account has this role.
* @return bool
*/functionhas(Role storage role, address account) internalviewreturns (bool) {
require(account !=address(0));
return role.bearer[account];
}
}
Contract Source Code
File 10 of 10: SafeMath.sol
pragmasolidity ^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.
*/librarySafeMath{
/**
* @dev Returns the addition of two unsigned integers, reverting on
* overflow.
*
* Counterpart to Solidity's `+` operator.
*
* Requirements:
* - Addition cannot overflow.
*/functionadd(uint256 a, uint256 b) internalpurereturns (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.
*/functionsub(uint256 a, uint256 b) internalpurereturns (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.
*/functionmul(uint256 a, uint256 b) internalpurereturns (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/522if (a ==0) {
return0;
}
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.
*/functiondiv(uint256 a, uint256 b) internalpurereturns (uint256) {
// Solidity only automatically asserts when dividing by 0require(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 holdreturn 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.
*/functionmod(uint256 a, uint256 b) internalpurereturns (uint256) {
require(b !=0, "SafeMath: modulo by zero");
return a % b;
}
}