Topic: ECASH - page 49. (Read 80432 times)

pragma solidity ^0.4.13;

interface tokenRecipient { function receiveApproval(address _from, uint256 _value, address _token, bytes _extraData) public; }

contract TokenERC20 {
    // 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;

    // This creates an array with all balances
    mapping (address => uint256) public balanceOf;
    mapping (address => mapping (address => uint256)) public allowance;

    // This generates a public event on the blockchain that will notify clients
    event Transfer(address indexed from, address indexed to, uint256 value);

    // 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 TokenERC20(
        uint256 initialSupply,
        string tokenName,
        string tokenSymbol
    ) public {
        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
    }

    /**
     * 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 {
        _transfer(msg.sender, _to, _value);
    }

    /**
     * Transfer tokens from other address
     *
     * Send `_value` tokens to `_to` in 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 in 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 in 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 ccount
     *
     * 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;
    }
}

0x606060405236156100b75763ffffffff7c010000000000000000000000000000000000000000000000000000000060003504166306fdde0381146100bc578063095ea7b31461014757806318160ddd1461017d57806323b872dd146101a2578063313ce567146101de57806342966c681461020757806370a082311461023157806379cc67901461026257806395d89b4114610298578063a9059cbb14610323578063cae9ca5114610347578063dd62ed3e146103c0575b600080fd5b34156100c757600080fd5b6100cf6103f7565b60405160208082528190810183818151815260200191508051906020019080838360005b8381101561010c5780820151818401525b6020016100f3565b50505050905090810190601f1680156101395780820380516001836020036101000a031916815260200191505b509250505060405180910390f35b341561015257600080fd5b610169600160a060020a0360043516602435610495565b604051901515815260200160405180910390f35b341561018857600080fd5b6101906104c6565b60405190815260200160405180910390f35b34156101ad57600080fd5b610169600160a060020a03600435811690602435166044356104cc565b604051901515815260200160405180910390f35b34156101e957600080fd5b6101f1610544565b60405160ff909116815260200160405180910390f35b341561021257600080fd5b61016960043561054d565b604051901515815260200160405180910390f35b341561023c57600080fd5b610190600160a060020a03600435166105d9565b60405190815260200160405180910390f35b341561026d57600080fd5b610169600160a060020a03600435166024356105eb565b604051901515815260200160405180910390f35b34156102a357600080fd5b6100cf6106c8565b60405160208082528190810183818151815260200191508051906020019080838360005b8381101561010c5780820151818401525b6020016100f3565b50505050905090810190601f1680156101395780820380516001836020036101000a031916815260200191505b509250505060405180910390f35b341561032e57600080fd5b610345600160a060020a0360043516602435610766565b005b341561035257600080fd5b61016960048035600160a060020a03169060248035919060649060443590810190830135806020601f8201819004810201604051908101604052818152929190602084018383808284375094965061077695505050505050565b604051901515815260200160405180910390f35b34156103cb57600080fd5b610190600160a060020a03600435811690602435166108aa565b60405190815260200160405180910390f35b60008054600181600116156101000203166002900480601f01602080910402602001604051908101604052809291908181526020018280546001816001161561010002031660029004801561048d5780601f106104625761010080835404028352916020019161048d565b820191906000526020600020905b81548152906001019060200180831161047057829003601f168201915b505050505081565b600160a060020a03338116600090815260056020908152604080832093861683529290522081905560015b92915050565b60035481565b600160a060020a0380841660009081526005602090815260408083203390941683529290529081205482111561050157600080fd5b600160a060020a03808516600090815260056020908152604080832033909416835292905220805483900390556105398484846108c7565b5060015b9392505050565b60025460ff1681565b600160a060020a0333166000908152600460205260408120548290101561057357600080fd5b600160a060020a03331660008181526004602052604090819020805485900390556003805485900390557fcc16f5dbb4873280815c1ee09dbd06736cffcc184412cf7a71a0fdb75d397ca59084905190815260200160405180910390a25060015b919050565b60046020526000908152604090205481565b600160a060020a0382166000908152600460205260408120548290101561061157600080fd5b600160a060020a038084166000908152600560209081526040808320339094168352929052205482111561064457600080fd5b600160a060020a038084166000818152600460209081526040808320805488900390556005825280832033909516835293905282902080548590039055600380548590039055907fcc16f5dbb4873280815c1ee09dbd06736cffcc184412cf7a71a0fdb75d397ca59084905190815260200160405180910390a25060015b92915050565b60018054600181600116156101000203166002900480601f01602080910402602001604051908101604052809291908181526020018280546001816001161561010002031660029004801561048d5780601f106104625761010080835404028352916020019161048d565b820191906000526020600020905b81548152906001019060200180831161047057829003601f168201915b505050505081565b6107713383836108c7565b5b5050565b6000836107838185610495565b156108a15780600160a060020a0316638f4ffcb1338630876040518563ffffffff167c01000000000000000000000000000000000000000000000000000000000281526004018085600160a060020a0316600160a060020a0316815260200184815260200183600160a060020a0316600160a060020a0316815260200180602001828103825283818151815260200191508051906020019080838360005b8381101561083a5780820151818401525b602001610821565b50505050905090810190601f1680156108675780820380516001836020036101000a031916815260200191505b5095505050505050600060405180830381600087803b151561088857600080fd5b6102c65a03f1151561089957600080fd5b505050600191505b5b509392505050565b600560209081526000928352604080842090915290825290205481565b6000600160a060020a03831615156108de57600080fd5b600160a060020a0384166000908152600460205260409020548290101561090457600080fd5b600160a060020a0383166000908152600460205260409020548281011161092a57600080fd5b50600160a060020a0380831660008181526004602052604080822080549488168084528284208054888103909155938590528154870190915591909301927fddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef9085905190815260200160405180910390a3600160a060020a038084166000908152600460205260408082205492871682529020540181146109c757fe5b5b505050505600a165627a7a72305820afcd2e496c90ced90d96012acfd925f4c5505f88cfd11381339ee4b11d5851570029