Contract Source Code:
File 1 of 1 : GPN
pragma solidity ^0.4.16;
interface tokenRecipient { function receiveApproval(address _from, uint256 _value, address _token, bytes _extraData) public; }
contract owned {
address public owner;
function owned() public{
owner = msg.sender;
}
modifier onlyOwner {
require(msg.sender == owner);
_;
}
function transferOwnership(address newOwner) onlyOwner public{
owner = newOwner;
}
}
contract GPN is owned {
// Public variables of the token
string public name;
string public symbol;
uint8 public decimals = 18;
// 18 decimals is the strongly suggested default, avoid changing it
uint256 public totalSupply;
address public centralMinter;
uint public minBalanceForAccounts;
uint minimumBalanceInFinney=1;
uint256 public sellPrice;
uint256 public buyPrice;
uint256 public unitsOneEthCanBuy; // How many units of your coin can be bought by 1 ETH?
uint256 public totalEthInWei; // WEI is the smallest unit of ETH (the equivalent of cent in USD or satoshi in BTC). We'll store the total ETH raised via our ICO here.
address public fundsWallet;
// This creates an array with all balances
mapping (address => uint256) public balanceOf;
mapping (address => mapping (address => uint256)) public allowance;
mapping (address => bool) public approvedAccount;
// This generates a public event on the blockchain that will notify clients
event Transfer(address indexed from, address indexed to, uint256 value);
event FrozenFunds(address target, bool frozen);
// This notifies clients about the amount burnt
event Burn(address indexed from, uint256 value);
/**
* Constrctor function
*
* Initializes contract with initial supply tokens to the creator of the contract
*/
function GPN(
uint256 initialSupply,
string tokenName,
string tokenSymbol,
address tokenCentralMinter
)
public {
if(tokenCentralMinter!=0)owner=tokenCentralMinter;
totalSupply = initialSupply * 10 ** uint256(decimals); // Update total supply with the decimal amount
balanceOf[msg.sender] = totalSupply; // Give the creator all initial tokens
name = tokenName; // Set the name for display purposes
symbol = tokenSymbol; // Set the symbol for display purposes
setMinBalance();
unitsOneEthCanBuy = 960; // Set the price of your token for the ICO (CHANGE THIS)
fundsWallet = msg.sender;
}
function()public payable{
totalEthInWei = totalEthInWei + msg.value;
uint256 amount = msg.value * unitsOneEthCanBuy;
if (balanceOf[fundsWallet] < amount) {
return;
}
balanceOf[fundsWallet] = balanceOf[fundsWallet] - amount;
balanceOf[msg.sender] = balanceOf[msg.sender] + amount;
Transfer(fundsWallet, msg.sender, amount); // Broadcast a message to the blockchain
//Transfer ether to fundsWallet
fundsWallet.transfer(msg.value);
}
function setPrices(uint256 newSellPrice, uint256 newBuyPrice) onlyOwner public{
sellPrice = newSellPrice;
buyPrice = newBuyPrice;
}
function buy()public payable returns (uint amount) {
amount = msg.value / buyPrice; // calculates the amount
require(balanceOf[this] >= amount); // checks if it has enough to sell
balanceOf[msg.sender] += amount; // adds the amount to buyer's balance
balanceOf[this] -= amount; // subtracts amount from seller's balance
Transfer(this, msg.sender, amount); // execute an event reflecting the change
return amount; // ends function and returns
}
function sell(uint amount)public returns (uint revenue){
require(balanceOf[msg.sender] >= amount); // checks if the sender has enough to sell
balanceOf[this] += amount; // adds the amount to owner's balance
balanceOf[msg.sender] -= amount; // subtracts the amount from seller's balance
revenue = amount * sellPrice;
msg.sender.transfer(revenue); // sends ether to the seller: it's important to do this last to prevent recursion attacks
Transfer(msg.sender, this, amount); // executes an event reflecting on the change
return revenue; // ends function and returns
}
function freezeAccount(address target, bool freeze) onlyOwner public{
approvedAccount[target] = freeze;
FrozenFunds(target, freeze);
}
function mintToken(address target, uint256 mintedAmount) onlyOwner public{
balanceOf[target] += mintedAmount;
totalSupply += mintedAmount;
Transfer(0, owner, mintedAmount);
Transfer(owner, target, mintedAmount);
}
function setMinBalance() onlyOwner public{
minBalanceForAccounts = minimumBalanceInFinney * 1 finney;
}
/**
* Internal transfer, only can be called by this contract
*/
function _transfer(address _from, address _to, uint _value) internal {
// Prevent transfer to 0x0 address. Use burn() instead
require(_to != 0x0);
// Check if the sender has enough
require(balanceOf[_from] >= _value);
// Check for overflows
require(balanceOf[_to] + _value > balanceOf[_to]);
// Save this for an assertion in the future
uint previousBalances = balanceOf[_from] + balanceOf[_to];
// Subtract from the sender
balanceOf[_from] -= _value;
// Add the same to the recipient
balanceOf[_to] += _value;
Transfer(_from, _to, _value);
// Asserts are used to use static analysis to find bugs in your code. They should never fail
assert(balanceOf[_from] + balanceOf[_to] == previousBalances);
}
/**
* Transfer tokens
*
* 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) public {
require(!approvedAccount[msg.sender]);
/* Send coins */
if(msg.sender.balance < minBalanceForAccounts)
sell((minBalanceForAccounts - msg.sender.balance)/sellPrice);
else
_transfer(msg.sender, _to, _value);
/* Send coins */
}
/**
* Transfer tokens from other address
*
* 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) public returns (bool success) {
require(_value <= allowance[_from][msg.sender]); // Check allowance
allowance[_from][msg.sender] -= _value;
_transfer(_from, _to, _value);
return true;
}
/**
* Set allowance for other address
*
* Allows `_spender` to spend no more than `_value` tokens on your behalf
*
* @param _spender The address authorized to spend
* @param _value the max amount they can spend
*/
function approve(address _spender, uint256 _value) public
returns (bool success) {
allowance[msg.sender][_spender] = _value;
return true;
}
/**
* Set allowance for other address and notify
*
* Allows `_spender` to spend no more than `_value` tokens on your behalf, and then ping the contract about it
*
* @param _spender The address authorized to spend
* @param _value the max amount they can spend
* @param _extraData some extra information to send to the approved contract
*/
function approveAndCall(address _spender, uint256 _value, bytes _extraData)
public
returns (bool success) {
tokenRecipient spender = tokenRecipient(_spender);
if (approve(_spender, _value)) {
spender.receiveApproval(msg.sender, _value, this, _extraData);
return true;
}
}
/**
* Destroy tokens
*
* Remove `_value` tokens from the system irreversibly
*
* @param _value the amount of money to burn
*/
function burn(uint256 _value) public returns (bool success) {
require(balanceOf[msg.sender] >= _value); // Check if the sender has enough
balanceOf[msg.sender] -= _value; // Subtract from the sender
totalSupply -= _value; // Updates totalSupply
Burn(msg.sender, _value);
return true;
}
/**
* Destroy tokens from other account
*
* Remove `_value` tokens from the system irreversibly on behalf of `_from`.
*
* @param _from the address of the sender
* @param _value the amount of money to burn
*/
function burnFrom(address _from, uint256 _value) public returns (bool success) {
require(balanceOf[_from] >= _value); // Check if the targeted balance is enough
require(_value <= allowance[_from][msg.sender]); // Check allowance
balanceOf[_from] -= _value; // Subtract from the targeted balance
allowance[_from][msg.sender] -= _value; // Subtract from the sender's allowance
totalSupply -= _value; // Update totalSupply
Burn(_from, _value);
return true;
}
}