Contract Source Code:
File 1 of 1 : Erc20
pragma solidity ^0.4.13;
contract IERC20 {
function totalSupply() constant returns (uint _totalSupply);
function balanceOf(address _owner) constant returns (uint balance);
function transfer(address _to, uint _value) returns (bool success);
function transferFrom(address _from, address _to, uint _value) returns (bool success);
function approve(address _spender, uint _value) returns (bool success);
function allowance(address _owner, address _spender) constant returns (uint remaining);
event Transfer(address indexed _from, address indexed _to, uint _value);
event Approval(address indexed _owner, address indexed _spender, uint _value);
}
library SafeMathLib {
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 && c>=b);
return c;
}
}
/**
* @title Ownable
* @notice 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;
/**
* @notice The Ownable constructor sets the original `owner` of the contract to the sender
* account.
*/
function Ownable() {
owner = msg.sender;
}
/**
* @notice Throws if called by any account other than the owner.
*/
modifier onlyOwner() {
require(msg.sender == owner);
_;
}
/**
* @notice 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) onlyOwner {
require(newOwner != address(0));
owner = newOwner;
}
}
/**
* @title Erc20 Token
* @notice The ERC20 Token for Cove Identity.
*/
contract Erc20 is IERC20, Ownable {
using SafeMathLib for uint256;
uint256 public constant totalTokenSupply = 100000000 * 10**18;
string public name = "Dontoshi Token";
string public symbol = "DTD";
uint8 public constant decimals = 18;
mapping (address => uint256) public balances;
//approved[owner][spender]
mapping(address => mapping(address => uint256)) approved;
function Erc20() {
balances[msg.sender] = totalTokenSupply;
}
function totalSupply() constant returns (uint256 _totalSupply) {
return totalTokenSupply;
}
function balanceOf(address _owner) constant returns (uint256 balance) {
return balances[_owner];
}
/* Internal transfer, only can be called by this contract */
function _transfer(address _from, address _to, uint256 _value) internal {
require (_to != 0x0); // Prevent transfer to 0x0 address. Use burn() instead
require (balances[_from] >= _value); // Check if the sender has enough
require (balances[_to] + _value > balances[_to]); // Check for overflows
balances[_from] = balances[_from].minus(_value); // Subtract from the sender
balances[_to] = balances[_to].plus(_value); // Add the same to the recipient
Transfer(_from, _to, _value);
}
/**
* @notice Send `_value` tokens to `_to` from your account
* @param _to The address of the recipient
* @param _value the amount to send
*/
function transfer(address _to, uint256 _value) returns (bool success) {
_transfer(msg.sender, _to, _value);
return true;
}
/**
* @notice Send `_value` tokens to `_to` on behalf of `_from`
* @param _from The address of the sender
* @param _to The address of the recipient
* @param _value the amount to send
*/
function transferFrom(address _from, address _to, uint256 _value) returns (bool success) {
require (_value <= approved[_from][msg.sender]); // Check allowance
approved[_from][msg.sender] = approved[_from][msg.sender].minus(_value);
_transfer(_from, _to, _value);
return true;
}
/**
* @notice Approve `_value` tokens for `_spender`
* @param _spender The address of the sender
* @param _value the amount to send
*/
function approve(address _spender, uint256 _value) returns (bool success) {
if(balances[msg.sender] >= _value) {
approved[msg.sender][_spender] = _value;
Approval(msg.sender, _spender, _value);
return true;
}
return false;
}
/**
* @notice Check `_value` tokens allowed to `_spender` by `_owner`
* @param _owner The address of the Owner
* @param _spender The address of the Spender
*/
function allowance(address _owner, address _spender) constant returns (uint256 remaining) {
return approved[_owner][_spender];
}
event Transfer(address indexed _from, address indexed _to, uint256 _value);
event Approval(address indexed _owner, address indexed _spender, uint256 _value);
}