Contract Name:
TrueDeckToken
Contract Source Code:
File 1 of 1 : TrueDeckToken
pragma solidity 0.4.23;
/**
* @title SafeMath
* @dev Math operations with safety checks that throw on error
*/
library SafeMath {
/**
* @dev Multiplies two numbers, reverts on overflow.
*/
function mul(uint256 _a, uint256 _b) internal pure returns (uint256) {
if (_a == 0) {
return 0;
}
uint256 c = _a * _b;
require(c / _a == _b);
return c;
}
/**
* @dev Integer division of two numbers truncating the quotient, reverts on division by zero.
*/
function div(uint256 _a, uint256 _b) internal pure returns (uint256) {
require(_b > 0); // Solidity only automatically asserts 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, reverts on overflow (i.e. if subtrahend is greater than minuend).
*/
function sub(uint256 _a, uint256 _b) internal pure returns (uint256) {
require(_b <= _a);
uint256 c = _a - _b;
return c;
}
/**
* @dev Adds two numbers, throws on overflow.
*/
function add(uint256 _a, uint256 _b) internal pure returns (uint256) {
uint256 c = _a + _b;
require(c >= _a);
return c;
}
}
/**
* @title ERC20 interface
* @dev see https://github.com/ethereum/EIPs/issues/20
*/
contract ERC20 {
function totalSupply() public view returns (uint256);
function balanceOf(address _who) public view returns (uint256);
function allowance(address _owner, address _spender)
public view returns (uint256);
function transfer(address _to, uint256 _value) public returns (bool);
function approve(address _spender, uint256 _value)
public returns (bool);
function transferFrom(address _from, address _to, uint256 _value)
public returns (bool);
event Transfer(
address indexed from,
address indexed to,
uint256 value
);
event Approval(
address indexed owner,
address indexed spender,
uint256 value
);
}
/**
* @title TrueDeck TDP Token
* @dev ERC20 Token for TrueDeck Platform
*/
contract TrueDeckToken is ERC20 {
using SafeMath for uint256;
string public constant name = "TrueDeck";
string public constant symbol = "TDP";
uint8 public constant decimals = 18;
mapping (address => uint256) private balances_;
mapping (address => mapping (address => uint256)) private allowed_;
uint256 private totalSupply_;
/**
* @dev Initial supply of TDP tokens.
* 200M TDP Tokens
*/
uint256 public INITIAL_SUPPLY = 200000000 * 10 ** uint256(decimals);
constructor() public {
balances_[msg.sender] = INITIAL_SUPPLY;
totalSupply_ = INITIAL_SUPPLY;
}
/**
* @dev total number of tokens in existence
*/
function totalSupply() public view returns (uint256) {
return totalSupply_;
}
/**
* @dev Transfer the specified amount of tokens to the specified address.
* This function works the same with the previous one
* but doesn't contain `_data` param.
* Added due to backwards compatibility reasons.
* @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 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;
}
/**
* @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];
}
}