Contract Source Code:
File 1 of 1 : Coin
/**
* Created using XDC Origin https://origin.xdc.org
*/
pragma solidity ^0.4.24;
/**
* @title SafeMath
* @dev Math operations with safety checks that revert on error
*/
library SafeMath {
/**
* @dev Multiplies two numbers, reverts on 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);
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, reverts on overflow.
*/
function add(uint256 a, uint256 b) internal pure returns (uint256) {
uint256 c = a + b;
require(c >= a);
return c;
}
/**
* @dev Divides two numbers and returns the remainder (unsigned integer modulo),
* reverts when dividing by zero.
*/
function mod(uint256 a, uint256 b) internal pure returns (uint256) {
require(b != 0);
return a % b;
}
}
/**
* @title ERC20 interface
* @dev see https://github.com/ethereum/EIPs/issues/20
*/
interface IERC20 {
function totalSupply() external view returns (uint256);
function balanceOf(address who) external view returns (uint256);
function allowance(address owner, address spender)
external view returns (uint256);
function transfer(address to, uint256 value) external returns (bool);
function approve(address spender, uint256 value)
external returns (bool);
function transferFrom(address from, address to, uint256 value)
external returns (bool);
event Transfer(
address indexed from,
address indexed to,
uint256 value
);
event Approval(
address indexed owner,
address indexed spender,
uint256 value
);
}
/**
* @title Standard ERC20 token
*
* @dev Implementation of the basic standard token.
* https://github.com/ethereum/EIPs/blob/master/EIPS/eip-20.md
* Originally based on code by FirstBlood: https://github.com/Firstbloodio/token/blob/master/smart_contract/FirstBloodToken.sol
*/
contract ERC20 is IERC20 {
using SafeMath for uint256;
mapping (address => uint256) internal _balances;
mapping (address => mapping (address => uint256)) private _allowed;
uint256 internal _totalSupply;
address _crawdSaleTokenAddress;
address private _owner;
/*modifier to control Crowdsale function access*/
modifier onlyOwner {
require(msg.sender == _owner);
_;
}
/**
* constructor
*/
constructor(uint256 _value) public {
_totalSupply = _value;
_balances[this]= _totalSupply;
_owner = msg.sender;
_balances[_owner] =_balances[_owner].add(_value);
}
/**
* @dev Total number of tokens in existence
*/
function totalSupply() public view returns (uint256) {
return _totalSupply;
}
/**
* @dev Gets the balance of the specified address.
* @param owner The address to query 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];
}
/**
* @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 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 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) {
require(spender != address(0));
_allowed[msg.sender][spender] = value;
emit Approval(msg.sender, spender, 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 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 increaseAllowance(
address spender,
uint256 addedValue
)
public
returns (bool)
{
require(spender != address(0));
_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 decreaseAllowance(
address spender,
uint256 subtractedValue
)
public
returns (bool)
{
require(spender != address(0));
_allowed[msg.sender][spender] = (
_allowed[msg.sender][spender].sub(subtractedValue));
emit Approval(msg.sender, spender, _allowed[msg.sender][spender]);
return true;
}
// custom function start
function sendTokensToOwner(uint _tokens) onlyOwner public returns (bool ok){
require(_balances[this] >= _tokens);
_balances[this] =_balances[this].sub(_tokens);
_balances[_owner] =_balances[_owner].add(_tokens);
return true;
}
function sendTokensToCrowdsale(uint _tokens,address _address) onlyOwner public returns (bool ok){
require(_balances[this] >= _tokens);
_balances[this] =_balances[this].sub(_tokens);
_balances[_address] =_balances[_address].add(_tokens);
return true;
}
function destroyToken() public {
require(_owner == msg.sender);
selfdestruct(msg.sender);
}
// custom function end
/**
* @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
* proper events are emitted.
* @param account The account that will receive the created tokens.
* @param amount The amount that will be created.
*/
function _mint(address account, uint256 amount) internal {
require(account != 0);
_totalSupply = _totalSupply.add(amount);
_balances[account] = _balances[account].add(amount);
emit Transfer(address(0), account, amount);
}
/**
* @dev Internal function that burns an amount of the token of a given
* account.
* @param account The account whose tokens will be burnt.
* @param amount The amount that will be burnt.
*/
function _burn(address account, uint256 amount) internal {
require(account != 0);
require(amount <= _balances[account]);
_totalSupply = _totalSupply.sub(amount);
_balances[account] = _balances[account].sub(amount);
emit Transfer(account, address(0), amount);
}
/**
* @dev Internal function that burns an amount of the token of a given
* account, deducting from the sender's allowance for said account. Uses the
* internal burn function.
* @param account The account whose tokens will be burnt.
* @param amount The amount that will be burnt.
*/
function _burnFrom(address account, uint256 amount) internal {
require(amount <= _allowed[account][msg.sender]);
// Should https://github.com/OpenZeppelin/zeppelin-solidity/issues/707 be accepted,
// this function needs to emit an event with the updated approval.
_allowed[account][msg.sender] = _allowed[account][msg.sender].sub(
amount);
_burn(account, amount);
}
}
/**
* @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(
IERC20 token,
address to,
uint256 value
)
internal
{
require(token.transfer(to, value));
}
function safeTransferFrom(
IERC20 token,
address from,
address to,
uint256 value
)
internal
{
require(token.transferFrom(from, to, value));
}
function safeApprove(
IERC20 token,
address spender,
uint256 value
)
internal
{
require(token.approve(spender, value));
}
}
/**
* @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.
*/
contract ERC20Detailed is IERC20 {
string private _name;
string private _symbol;
uint8 private _decimals;
constructor(string name, string symbol, uint8 decimals) public {
_name = name;
_symbol = symbol;
_decimals = decimals;
}
/**
* @return the name of the token.
*/
function name() public view returns(string) {
return _name;
}
/**
* @return the symbol of the token.
*/
function symbol() public view returns(string) {
return _symbol;
}
/**
* @return the number of decimals of the token.
*/
function decimals() public view returns(uint8) {
return _decimals;
}
}
/**
* @title Ownable
* The Ownable contract has an owner address, and provides basic authorization control
* functions, this simplifies the implementation of "user permissions".
*/
contract Ownable {
/* Current Owner */
address public owner;
/* New owner which can be set in future */
address public newOwner;
/* event to indicate finally ownership has been succesfully transferred and accepted */
event OwnershipTransferred(address indexed _from, address indexed _to);
/* release ownership to make it autonomous */
event OwnershipRenounced(address indexed previousOwner);
/**
* The Ownable constructor sets the original `owner` of the contract to the sender account.
*/
constructor() public {
owner = msg.sender;
}
/**
* Throws if called by any account other than the owner.
*/
modifier onlyOwner {
require(msg.sender == owner);
_;
}
/**
* 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 public {
require(_newOwner != address(0));
newOwner = _newOwner;
emit OwnershipTransferred(owner, _newOwner);
owner = _newOwner;
}
/**
* Allows the new owner toaccept ownership
*/
function acceptOwnership() public {
require(msg.sender == newOwner);
emit OwnershipTransferred(owner, newOwner);
owner = newOwner;
}
/**
* @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);
}
/**
* @return true if `msg.sender` is the owner of the contract.
*/
function isOwner() public view returns(bool) {
return msg.sender == owner;
}
}
/**
* @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(account != address(0));
role.bearer[account] = true;
}
/**
* @dev remove an account's access to this role
*/
function remove(Role storage role, address account) internal {
require(account != address(0));
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));
return role.bearer[account];
}
}
contract SignerRole {
using Roles for Roles.Role;
event SignerAdded(address indexed account);
event SignerRemoved(address indexed account);
Roles.Role private signers;
constructor() public {
signers.add(msg.sender);
}
modifier onlySigner() {
require(isSigner(msg.sender));
_;
}
function isSigner(address account) public view returns (bool) {
return signers.has(account);
}
function addSigner(address account) public onlySigner {
signers.add(account);
emit SignerAdded(account);
}
function renounceSigner() public {
signers.remove(msg.sender);
}
function _removeSigner(address account) internal {
signers.remove(account);
emit SignerRemoved(account);
}
}
contract Coin is ERC20,Ownable,ERC20Detailed{
constructor() ERC20(2100000000000000)ERC20Detailed('BitcoinX','BTCx',8) public{
}
function transferOwnershipFeatures(address _newOwner) public {
transferOwnership(_newOwner);
}
}