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// SPDX-License-Identifier: MIT | |
/** | |
*Submitted for verification at Etherscan.io on 2021-07-15 | |
*/ | |
pragma solidity ^0.8.0; | |
/** | |
* @dev Wrappers over Solidity's arithmetic operations with added overflow | |
* checks. | |
* | |
* Arithmetic operations in Solidity wrap on overflow. This can easily result | |
* in bugs, because programmers usually assume that an overflow raises an | |
* error, which is the standard behavior in high level programming languages. | |
* `SafeMath` restores this intuition by reverting the transaction when an | |
* operation overflows. | |
* | |
* Using this library instead of the unchecked operations eliminates an entire | |
* class of bugs, so it's recommended to use it always. | |
*/ | |
library SafeMath { | |
/** | |
* @dev Returns the addition of two unsigned integers, reverting on | |
* overflow. | |
* | |
* Counterpart to Solidity's `+` operator. | |
* | |
* Requirements: | |
* - Addition cannot overflow. | |
*/ | |
function add(uint256 a, uint256 b) internal pure returns (uint256) { | |
uint256 c = a + b; | |
require(c >= a, "SafeMath: addition overflow"); | |
return c; | |
} | |
/** | |
* @dev Returns the subtraction of two unsigned integers, reverting on | |
* overflow (when the result is negative). | |
* | |
* Counterpart to Solidity's `-` operator. | |
* | |
* Requirements: | |
* - Subtraction cannot overflow. | |
*/ | |
function sub(uint256 a, uint256 b) internal pure returns (uint256) { | |
return sub(a, b, "SafeMath: subtraction overflow"); | |
} | |
/** | |
* @dev Returns the subtraction of two unsigned integers, reverting with custom message on | |
* overflow (when the result is negative). | |
* | |
* Counterpart to Solidity's `-` operator. | |
* | |
* Requirements: | |
* - Subtraction cannot overflow. | |
* | |
* _Available since v2.4.0._ | |
*/ | |
function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) { | |
require(b <= a, errorMessage); | |
uint256 c = a - b; | |
return c; | |
} | |
/** | |
* @dev Returns the multiplication of two unsigned integers, reverting on | |
* overflow. | |
* | |
* Counterpart to Solidity's `*` operator. | |
* | |
* Requirements: | |
* - Multiplication cannot 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-contracts/pull/522 | |
if (a == 0) { | |
return 0; | |
} | |
uint256 c = a * b; | |
require(c / a == b, "SafeMath: multiplication overflow"); | |
return c; | |
} | |
/** | |
* @dev Returns the integer division of two unsigned integers. Reverts on | |
* division by zero. The result is rounded towards zero. | |
* | |
* Counterpart to Solidity's `/` operator. Note: this function uses a | |
* `revert` opcode (which leaves remaining gas untouched) while Solidity | |
* uses an invalid opcode to revert (consuming all remaining gas). | |
* | |
* Requirements: | |
* - The divisor cannot be zero. | |
*/ | |
function div(uint256 a, uint256 b) internal pure returns (uint256) { | |
return div(a, b, "SafeMath: division by zero"); | |
} | |
/** | |
* @dev Returns the integer division of two unsigned integers. Reverts with custom message on | |
* division by zero. The result is rounded towards zero. | |
* | |
* Counterpart to Solidity's `/` operator. Note: this function uses a | |
* `revert` opcode (which leaves remaining gas untouched) while Solidity | |
* uses an invalid opcode to revert (consuming all remaining gas). | |
* | |
* Requirements: | |
* - The divisor cannot be zero. | |
* | |
* _Available since v2.4.0._ | |
*/ | |
function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) { | |
// Solidity only automatically asserts when dividing by 0 | |
require(b > 0, errorMessage); | |
uint256 c = a / b; | |
// assert(a == b * c + a % b); // There is no case in which this doesn't hold | |
return c; | |
} | |
/** | |
* @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo), | |
* Reverts when dividing by zero. | |
* | |
* Counterpart to Solidity's `%` operator. This function uses a `revert` | |
* opcode (which leaves remaining gas untouched) while Solidity uses an | |
* invalid opcode to revert (consuming all remaining gas). | |
* | |
* Requirements: | |
* - The divisor cannot be zero. | |
*/ | |
function mod(uint256 a, uint256 b) internal pure returns (uint256) { | |
return mod(a, b, "SafeMath: modulo by zero"); | |
} | |
/** | |
* @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo), | |
* Reverts with custom message when dividing by zero. | |
* | |
* Counterpart to Solidity's `%` operator. This function uses a `revert` | |
* opcode (which leaves remaining gas untouched) while Solidity uses an | |
* invalid opcode to revert (consuming all remaining gas). | |
* | |
* Requirements: | |
* - The divisor cannot be zero. | |
* | |
* _Available since v2.4.0._ | |
*/ | |
function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) { | |
require(b != 0, errorMessage); | |
return a % b; | |
} | |
} | |
/** | |
* @dev Collection of functions related to the address type | |
*/ | |
library Address { | |
/** | |
* @dev Returns true if `account` is a contract. | |
* | |
* [IMPORTANT] | |
* ==== | |
* It is unsafe to assume that an address for which this function returns | |
* false is an externally-owned account (EOA) and not a contract. | |
* | |
* Among others, `isContract` will return false for the following | |
* types of addresses: | |
* | |
* - an externally-owned account | |
* - a contract in construction | |
* - an address where a contract will be created | |
* - an address where a contract lived, but was destroyed | |
* ==== | |
*/ | |
function isContract(address account) internal view returns (bool) { | |
// According to EIP-1052, 0x0 is the value returned for not-yet created accounts | |
// and 0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470 is returned | |
// for accounts without code, i.e. `keccak256('')` | |
bytes32 codehash; | |
bytes32 accountHash = 0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470; | |
// solhint-disable-next-line no-inline-assembly | |
assembly { codehash := extcodehash(account) } | |
return (codehash != accountHash && codehash != 0x0); | |
} | |
/** | |
* @dev Converts an `address` into `address payable`. Note that this is | |
* simply a type cast: the actual underlying value is not changed. | |
* | |
* _Available since v2.4.0._ | |
*/ | |
function toPayable(address account) internal pure returns (address payable) { | |
return payable(address(uint160(account))); | |
} | |
/** | |
* @dev Replacement for Solidity's `transfer`: sends `amount` wei to | |
* `recipient`, forwarding all available gas and reverting on errors. | |
* | |
* https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost | |
* of certain opcodes, possibly making contracts go over the 2300 gas limit | |
* imposed by `transfer`, making them unable to receive funds via | |
* `transfer`. {sendValue} removes this limitation. | |
* | |
* https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more]. | |
* | |
* IMPORTANT: because control is transferred to `recipient`, care must be | |
* taken to not create reentrancy vulnerabilities. Consider using | |
* {ReentrancyGuard} or the | |
* https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern]. | |
* | |
* _Available since v2.4.0._ | |
*/ | |
function sendValue(address payable recipient, uint256 amount) internal { | |
require(address(this).balance >= amount, "Address: insufficient balance"); | |
// solhint-disable-next-line avoid-call-value | |
(bool success, ) = recipient.call{value : amount}(""); | |
require(success, "Address: unable to send value, recipient may have reverted"); | |
} | |
} | |
/** | |
* @title SafeERC20 | |
* @dev Wrappers around ERC20 operations that throw on failure (when the token | |
* contract returns false). Tokens that return no value (and instead revert or | |
* throw on failure) are also supported, non-reverting calls are assumed to be | |
* successful. | |
* 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 { | |
using SafeMath for uint256; | |
using Address for address; | |
function safeTransfer(IERC20 token, address to, uint256 value) internal { | |
callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value)); | |
} | |
function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal { | |
callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value)); | |
} | |
function safeApprove(IERC20 token, address spender, uint256 value) internal { | |
// safeApprove should only be called when setting an initial allowance, | |
// or when resetting it to zero. To increase and decrease it, use | |
// 'safeIncreaseAllowance' and 'safeDecreaseAllowance' | |
// solhint-disable-next-line max-line-length | |
require((value == 0) || (token.allowance(address(this), spender) == 0), | |
"SafeERC20: approve from non-zero to non-zero allowance" | |
); | |
callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value)); | |
} | |
function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal { | |
uint256 newAllowance = token.allowance(address(this), spender).add(value); | |
callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance)); | |
} | |
function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal { | |
uint256 newAllowance = token.allowance(address(this), spender).sub(value, "SafeERC20: decreased allowance below zero"); | |
callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance)); | |
} | |
/** | |
* @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement | |
* on the return value: the return value is optional (but if data is returned, it must not be false). | |
* @param token The token targeted by the call. | |
* @param data The call data (encoded using abi.encode or one of its variants). | |
*/ | |
function callOptionalReturn(IERC20 token, bytes memory data) private { | |
// We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since | |
// we're implementing it ourselves. | |
// A Solidity high level call has three parts: | |
// 1. The target address is checked to verify it contains contract code | |
// 2. The call itself is made, and success asserted | |
// 3. The return value is decoded, which in turn checks the size of the returned data. | |
// solhint-disable-next-line max-line-length | |
require(address(token).isContract(), "SafeERC20: call to non-contract"); | |
// solhint-disable-next-line avoid-low-level-calls | |
(bool success, bytes memory returndata) = address(token).call(data); | |
require(success, "SafeERC20: low-level call failed"); | |
if (returndata.length > 0) { // Return data is optional | |
// solhint-disable-next-line max-line-length | |
require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed"); | |
} | |
} | |
} | |
/** | |
* @dev Contract module that helps prevent reentrant calls to a function. | |
* | |
* Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier | |
* available, which can be applied to functions to make sure there are no nested | |
* (reentrant) calls to them. | |
* | |
* Note that because there is a single `nonReentrant` guard, functions marked as | |
* `nonReentrant` may not call one another. This can be worked around by making | |
* those functions `private`, and then adding `external` `nonReentrant` entry | |
* points to them. | |
* | |
* TIP: If you would like to learn more about reentrancy and alternative ways | |
* to protect against it, check out our blog post | |
* https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul]. | |
* | |
* _Since v2.5.0:_ this module is now much more gas efficient, given net gas | |
* metering changes introduced in the Istanbul hardfork. | |
*/ | |
contract ReentrancyGuard { | |
bool private _notEntered; | |
constructor () { | |
// Storing an initial non-zero value makes deployment a bit more | |
// expensive, but in exchange the refund on every call to nonReentrant | |
// will be lower in amount. Since refunds are capped to a percetange of | |
// the total transaction's gas, it is best to keep them low in cases | |
// like this one, to increase the likelihood of the full refund coming | |
// into effect. | |
_notEntered = true; | |
} | |
/** | |
* @dev Prevents a contract from calling itself, directly or indirectly. | |
* Calling a `nonReentrant` function from another `nonReentrant` | |
* function is not supported. It is possible to prevent this from happening | |
* by making the `nonReentrant` function external, and make it call a | |
* `private` function that does the actual work. | |
*/ | |
modifier nonReentrant() { | |
// On the first call to nonReentrant, _notEntered will be true | |
require(_notEntered, "ReentrancyGuard: reentrant call"); | |
// Any calls to nonReentrant after this point will fail | |
_notEntered = false; | |
_; | |
// By storing the original value once again, a refund is triggered (see | |
// https://eips.ethereum.org/EIPS/eip-2200) | |
_notEntered = true; | |
} | |
} | |
/* | |
* @dev Provides information about the current execution context, including the | |
* sender of the transaction and its data. While these are generally available | |
* via msg.sender and msg.data, they should not be accessed in such a direct | |
* manner, since when dealing with GSN meta-transactions the account sending and | |
* paying for execution may not be the actual sender (as far as an application | |
* is concerned). | |
* | |
* This contract is only required for intermediate, library-like contracts. | |
*/ | |
contract Context { | |
// Empty internal constructor, to prevent people from mistakenly deploying | |
// an instance of this contract, which should be used via inheritance. | |
constructor () { } | |
// solhint-disable-previous-line no-empty-blocks | |
function _msgSender() internal view returns (address payable) { | |
return payable(msg.sender); | |
} | |
function _msgData() internal view returns (bytes memory) { | |
this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691 | |
return msg.data; | |
} | |
} | |
/** | |
* @title Crowdsale | |
* @dev Crowdsale is a base contract for managing a token crowdsale, | |
* allowing investors to purchase tokens with ether. This contract implements | |
* such functionality in its most fundamental form and can be extended to provide additional | |
* functionality and/or custom behavior. | |
* The external interface represents the basic interface for purchasing tokens, and conforms | |
* the base architecture for crowdsales. It is *not* intended to be modified / overridden. | |
* The internal interface conforms the extensible and modifiable surface of crowdsales. Override | |
* the methods to add functionality. Consider using 'super' where appropriate to concatenate | |
* behavior. | |
*/ | |
contract Crowdsale is Context, ReentrancyGuard { | |
using SafeMath for uint256; | |
using SafeERC20 for IERC20; | |
// The token being sold | |
IERC20 private _token; | |
// Address where funds are collected | |
address payable private _wallet; | |
// How many token units a buyer gets per wei. | |
// The rate is the conversion between wei and the smallest and indivisible token unit. | |
// So, if you are using a rate of 1 with a ERC20Detailed token with 3 decimals called TOK | |
// 1 wei will give you 1 unit, or 0.001 TOK. | |
uint256 private _rate; | |
// Amount of wei raised | |
uint256 private _weiRaised; | |
/** | |
* Event for token purchase logging | |
* @param purchaser who paid for the tokens | |
* @param beneficiary who got the tokens | |
* @param value weis paid for purchase | |
* @param amount amount of tokens purchased | |
*/ | |
event TokensPurchased(address indexed purchaser, address indexed beneficiary, uint256 value, uint256 amount); | |
event Received(address, uint); | |
/** | |
* @param Rate Number of Token units a buyer gets per wei | |
* @dev The Rate is the conversion between wei and the smallest and indivisible | |
* Token unit. So, if you are using a rate of 1 with a ERC20Detailed Token | |
* with 3 decimals called TOK, 1 wei will give you 1 unit, or 0.001 TOK. | |
* @param Wallet Address where collected funds will be forwarded to | |
* @param Token Address of the token being sold | |
*/ | |
// altered : token = Token, wallet = Wallet, rate = Rate | |
constructor (uint256 Rate, address payable Wallet, IERC20 Token) { | |
require(Rate > 0, "Crowdsale: rate is 0"); | |
require(Wallet != address(0), "Crowdsale: wallet is the zero address"); | |
require(address(Token) != address(0), "Crowdsale: token is the zero address"); | |
_rate = Rate; | |
_wallet = Wallet; | |
_token = Token; | |
} | |
/** | |
* @dev fallback function ***DO NOT OVERRIDE*** | |
* Note that other contracts will transfer funds with a base gas stipend | |
* of 2300, which is not enough to call buyTokens. Consider calling | |
* buyTokens directly when purchasing tokens from a contract. | |
*/ | |
fallback () external payable { | |
buyTokens(_msgSender()); | |
} | |
receive() external payable { | |
emit Received(msg.sender, msg.value); | |
} | |
/** | |
* @return the token being sold. | |
*/ | |
function token() public view returns (IERC20) { | |
return _token; | |
} | |
/** | |
* @return the address where funds are collected. | |
*/ | |
function wallet() public view returns (address payable) { | |
return _wallet; | |
} | |
/** | |
* @return the number of token units a buyer gets per wei. | |
*/ | |
function rate() public view returns (uint256) { | |
return _rate; | |
} | |
/** | |
* @return the amount of wei raised. | |
*/ | |
function weiRaised() public view returns (uint256) { | |
return _weiRaised; | |
} | |
/** | |
* @dev low level token purchase ***DO NOT OVERRIDE*** | |
* This function has a non-reentrancy guard, so it shouldn't be called by | |
* another `nonReentrant` function. | |
* @param beneficiary Recipient of the token purchase | |
*/ | |
function buyTokens(address beneficiary) public nonReentrant payable { | |
uint256 weiAmount = msg.value; | |
_preValidatePurchase(beneficiary, weiAmount); | |
// calculate token amount to be created | |
uint256 tokens = _getTokenAmount(weiAmount); | |
// update state | |
_weiRaised = _weiRaised.add(weiAmount); | |
_processPurchase(beneficiary, tokens); | |
emit TokensPurchased(_msgSender(), beneficiary, weiAmount, tokens); | |
_updatePurchasingState(beneficiary, weiAmount); | |
_forwardFunds(); | |
_postValidatePurchase(beneficiary, weiAmount); | |
} | |
/** | |
* @dev Validation of an incoming purchase. Use require statements to revert state when conditions are not met. | |
* Use `super` in contracts that inherit from Crowdsale to extend their validations. | |
* Example from CappedCrowdsale.sol's _preValidatePurchase method: | |
* super._preValidatePurchase(beneficiary, weiAmount); | |
* require(weiRaised().add(weiAmount) <= cap); | |
* @param beneficiary Address performing the token purchase | |
* @param weiAmount Value in wei involved in the purchase | |
*/ | |
function _preValidatePurchase(address beneficiary, uint256 weiAmount) virtual internal view { | |
require(beneficiary != address(0), "Crowdsale: beneficiary is the zero address"); | |
require(weiAmount != 0, "Crowdsale: weiAmount is 0"); | |
this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691 | |
} | |
/** | |
* @dev Validation of an executed purchase. Observe state and use revert statements to undo rollback when valid | |
* conditions are not met. | |
* @param beneficiary Address performing the token purchase | |
* @param weiAmount Value in wei involved in the purchase | |
*/ | |
function _postValidatePurchase(address beneficiary, uint256 weiAmount) internal view { | |
// solhint-disable-previous-line no-empty-blocks | |
} | |
/** | |
* @dev Source of tokens. Override this method to modify the way in which the crowdsale ultimately gets and sends | |
* its tokens. | |
* @param beneficiary Address performing the token purchase | |
* @param tokenAmount Number of tokens to be emitted | |
*/ | |
function _deliverTokens(address beneficiary, uint256 tokenAmount) virtual internal { | |
_token.safeTransfer(beneficiary, tokenAmount); | |
} | |
/** | |
* @dev Executed when a purchase has been validated and is ready to be executed. Doesn't necessarily emit/send | |
* tokens. | |
* @param beneficiary Address receiving the tokens | |
* @param tokenAmount Number of tokens to be purchased | |
*/ | |
function _processPurchase(address beneficiary, uint256 tokenAmount) internal { | |
_deliverTokens(beneficiary, tokenAmount); | |
} | |
/** | |
* @dev Override for extensions that require an internal state to check for validity (current user contributions, | |
* etc.) | |
* @param beneficiary Address receiving the tokens | |
* @param weiAmount Value in wei involved in the purchase | |
*/ | |
function _updatePurchasingState(address beneficiary, uint256 weiAmount) internal { | |
// solhint-disable-previous-line no-empty-blocks | |
} | |
/** | |
* @dev Override to extend the way in which ether is converted to tokens. | |
* @param weiAmount Value in wei to be converted into tokens | |
* @return Number of tokens that can be purchased with the specified _weiAmount | |
*/ | |
function _getTokenAmount(uint256 weiAmount) internal view returns (uint256) { | |
return weiAmount.mul(_rate); | |
} | |
/** | |
* @dev Determines how ETH is stored/forwarded on purchases. | |
*/ | |
function _forwardFunds() virtual internal { | |
// address payable sibu = payable(0x420b99dA30a7123A646f1157414077Af4C9862Ee); | |
// uint256 div = msg.value*10/100 ; | |
// _wallet.transfer(div); | |
_wallet.transfer(msg.value); | |
} | |
} | |
/** | |
* @title CappedCrowdsale | |
* @dev Crowdsale with a limit for total contributions. | |
*/ | |
abstract contract CappedCrowdsale is Crowdsale { | |
using SafeMath for uint256; | |
uint256 private _cap; | |
/** | |
* @dev Constructor, takes maximum amount of wei accepted in the crowdsale. | |
* @param Cap Max amount of wei to be contributed | |
*/ | |
// Altering: converting cap to Cap to avoid warnings | |
constructor (uint256 Cap) { | |
require(Cap > 0, "CappedCrowdsale: cap is 0"); | |
_cap = Cap; | |
} | |
/** | |
* @return the cap of the crowdsale. | |
*/ | |
function cap() public view returns (uint256) { | |
return _cap; | |
} | |
/** | |
* @dev Checks whether the cap has been reached. | |
* @return Whether the cap was reached | |
*/ | |
function capReached() public view returns (bool) { | |
return weiRaised() >= _cap; | |
} | |
/** | |
* @dev Extend parent behavior requiring purchase to respect the funding cap. | |
* @param beneficiary Token purchaser | |
* @param weiAmount Amount of wei contributed | |
*/ | |
function _preValidatePurchase(address beneficiary, uint256 weiAmount) virtual internal view override { | |
super._preValidatePurchase(beneficiary, weiAmount); | |
require(weiRaised().add(weiAmount) <= _cap, "CappedCrowdsale: cap exceeded"); | |
} | |
} | |
/** | |
* @title TimedCrowdsale | |
* @dev Crowdsale accepting contributions only within a time frame. | |
*/ | |
abstract contract TimedCrowdsale is Crowdsale { | |
using SafeMath for uint256; | |
uint256 private _openingTime; | |
uint256 private _closingTime; | |
/** | |
* Event for crowdsale extending | |
* @param newClosingTime new closing time | |
* @param prevClosingTime old closing time | |
*/ | |
event TimedCrowdsaleExtended(uint256 prevClosingTime, uint256 newClosingTime); | |
/** | |
* @dev Reverts if not in crowdsale time range. | |
*/ | |
modifier onlyWhileOpen { | |
require(isOpen(), "TimedCrowdsale: not open"); | |
_; | |
} | |
/** | |
* @dev Constructor, takes crowdsale opening and closing times. | |
* @param OpeningTime Crowdsale opening time | |
* @param ClosingTime Crowdsale closing time | |
*/ | |
constructor (uint256 OpeningTime, uint256 ClosingTime) { | |
// solhint-disable-next-line not-rely-on-time | |
require(OpeningTime >= block.timestamp, "TimedCrowdsale: opening time is before current time"); | |
// solhint-disable-next-line max-line-length | |
require(ClosingTime > OpeningTime, "TimedCrowdsale: opening time is not before closing time"); | |
_openingTime = OpeningTime; | |
_closingTime = ClosingTime; | |
} | |
/** | |
* @return the crowdsale opening time. | |
*/ | |
function openingTime() public view returns (uint256) { | |
return _openingTime; | |
} | |
/** | |
* @return the crowdsale closing time. | |
*/ | |
function closingTime() public view returns (uint256) { | |
return _closingTime; | |
} | |
/** | |
* @return true if the crowdsale is open, false otherwise. | |
*/ | |
function isOpen() public view returns (bool) { | |
// solhint-disable-next-line not-rely-on-time | |
return block.timestamp >= _openingTime && block.timestamp <= _closingTime; | |
} | |
/** | |
* @dev Checks whether the period in which the crowdsale is open has already elapsed. | |
* @return Whether crowdsale period has elapsed | |
*/ | |
function hasClosed() public view returns (bool) { | |
// solhint-disable-next-line not-rely-on-time | |
return block.timestamp > _closingTime; | |
} | |
/** | |
* @dev Extend parent behavior requiring to be within contributing period. | |
* @param beneficiary Token purchaser | |
* @param weiAmount Amount of wei contributed | |
*/ | |
function _preValidatePurchase(address beneficiary, uint256 weiAmount) virtual override internal onlyWhileOpen view { | |
super._preValidatePurchase(beneficiary, weiAmount); | |
} | |
/** | |
* @dev Extend crowdsale. | |
* @param newClosingTime Crowdsale closing time | |
*/ | |
function _extendTime(uint256 newClosingTime) internal { | |
require(!hasClosed(), "TimedCrowdsale: already closed"); | |
// solhint-disable-next-line max-line-length | |
require(newClosingTime > _closingTime, "TimedCrowdsale: new closing time is before current closing time"); | |
emit TimedCrowdsaleExtended(_closingTime, newClosingTime); | |
_closingTime = newClosingTime; | |
} | |
} | |
/** | |
* @title FinalizableCrowdsale | |
* @dev Extension of TimedCrowdsale with a one-off finalization action, where one | |
* can do extra work after finishing. | |
*/ | |
abstract contract FinalizableCrowdsale is TimedCrowdsale { | |
using SafeMath for uint256; | |
bool private _finalized; | |
event CrowdsaleFinalized(); | |
constructor () { | |
_finalized = false; | |
} | |
/** | |
* @return true if the crowdsale is finalized, false otherwise. | |
*/ | |
function finalized() public view returns (bool) { | |
return _finalized; | |
} | |
/** | |
* @dev Must be called after crowdsale ends, to do some extra finalization | |
* work. Calls the contract's finalization function. | |
*/ | |
function finalize() public { | |
require(!_finalized, "FinalizableCrowdsale: already finalized"); | |
require(hasClosed(), "FinalizableCrowdsale: not closed"); | |
_finalized = true; | |
uint a = address(this).balance; | |
_finalization(); | |
emit CrowdsaleFinalized(); | |
} | |
/** | |
* @dev Can be overridden to add finalization logic. The overriding function | |
* should call super._finalization() to ensure the chain of finalization is | |
* executed entirely. | |
*/ | |
function _finalization() virtual internal { | |
// solhint-disable-previous-line no-empty-blocks | |
} | |
} | |
/** | |
* @dev A Secondary contract can only be used by its primary account (the one that created it). | |
*/ | |
contract Secondary is Context { | |
address private _primary; | |
/** | |
* @dev Emitted when the primary contract changes. | |
*/ | |
event PrimaryTransferred( | |
address recipient | |
); | |
/** | |
* @dev Sets the primary account to the one that is creating the Secondary contract. | |
*/ | |
constructor () { | |
address msgSender = _msgSender(); | |
_primary = msgSender; | |
emit PrimaryTransferred(msgSender); | |
} | |
/** | |
* @dev Reverts if called from any account other than the primary. | |
*/ | |
modifier onlyPrimary() { | |
require(_msgSender() == _primary, "Secondary: caller is not the primary account"); | |
_; | |
} | |
/** | |
* @return the address of the primary. | |
*/ | |
function primary() public view returns (address) { | |
return _primary; | |
} | |
/** | |
* @dev Transfers contract to a new primary. | |
* @param recipient The address of new primary. | |
*/ | |
function transferPrimary(address recipient) public onlyPrimary { | |
require(recipient != address(0), "Secondary: new primary is the zero address"); | |
_primary = recipient; | |
emit PrimaryTransferred(recipient); | |
} | |
} | |
/** | |
* @title Escrow | |
* @dev Base escrow contract, holds funds designated for a payee until they | |
* withdraw them. | |
* | |
* Intended usage: This contract (and derived escrow contracts) should be a | |
* standalone contract, that only interacts with the contract that instantiated | |
* it. That way, it is guaranteed that all Ether will be handled according to | |
* the `Escrow` rules, and there is no need to check for payable functions or | |
* transfers in the inheritance tree. The contract that uses the escrow as its | |
* payment method should be its primary, and provide public methods redirecting | |
* to the escrow's deposit and withdraw. | |
*/ | |
contract Escrow is Secondary { | |
using SafeMath for uint256; | |
using Address for address payable; | |
event Deposited(address indexed payee, uint256 weiAmount); | |
event Withdrawn(address indexed payee, uint256 weiAmount); | |
mapping(address => uint256) private _deposits; | |
function depositsOf(address payee) public view returns (uint256) { | |
return _deposits[payee]; | |
} | |
/** | |
* @dev Stores the sent amount as credit to be withdrawn. | |
* @param payee The destination address of the funds. | |
*/ | |
function deposit(address payee) virtual public onlyPrimary payable { | |
uint256 amount = msg.value; | |
_deposits[payee] = _deposits[payee].add(amount); | |
emit Deposited(payee, amount); | |
} | |
/** | |
* @dev Withdraw accumulated balance for a payee, forwarding 2300 gas (a | |
* Solidity `transfer`). | |
* | |
* NOTE: This function has been deprecated, use {withdrawWithGas} instead. | |
* Calling contracts with fixed-gas limits is an anti-pattern and may break | |
* contract interactions in network upgrades (hardforks). | |
* https://diligence.consensys.net/blog/2019/09/stop-using-soliditys-transfer-now/[Learn more.] | |
* | |
* @param payee The address whose funds will be withdrawn and transferred to. | |
*/ | |
function withdraw(address payable payee) virtual public onlyPrimary { | |
uint256 payment = _deposits[payee]; | |
_deposits[payee] = 0; | |
payee.transfer(payment); | |
emit Withdrawn(payee, payment); | |
} | |
/** | |
* @dev Same as {withdraw}, but forwarding all gas to the recipient. | |
* | |
* WARNING: Forwarding all gas opens the door to reentrancy vulnerabilities. | |
* Make sure you trust the recipient, or are either following the | |
* checks-effects-interactions pattern or using {ReentrancyGuard}. | |
* | |
* _Available since v2.4.0._ | |
*/ | |
function withdrawWithGas(address payable payee) public onlyPrimary { | |
uint256 payment = _deposits[payee]; | |
_deposits[payee] = 0; | |
payee.sendValue(payment); | |
emit Withdrawn(payee, payment); | |
} | |
} | |
/** | |
* @title ConditionalEscrow | |
* @dev Base abstract escrow to only allow withdrawal if a condition is met. | |
* @dev Intended usage: See {Escrow}. Same usage guidelines apply here. | |
*/ | |
abstract contract ConditionalEscrow is Escrow { | |
/** | |
* @dev Returns whether an address is allowed to withdraw their funds. To be | |
* implemented by derived contracts. | |
* @param payee The destination address of the funds. | |
*/ | |
function withdrawalAllowed(address payee) virtual public view returns (bool); | |
function withdraw(address payable payee) override public { | |
require(withdrawalAllowed(payee), "ConditionalEscrow: payee is not allowed to withdraw"); | |
super.withdraw(payee); | |
} | |
} | |
/** | |
* @title RefundEscrow | |
* @dev Escrow that holds funds for a beneficiary, deposited from multiple | |
* parties. | |
* @dev Intended usage: See {Escrow}. Same usage guidelines apply here. | |
* @dev The primary account (that is, the contract that instantiates this | |
* contract) may deposit, close the deposit period, and allow for either | |
* withdrawal by the beneficiary, or refunds to the depositors. All interactions | |
* with `RefundEscrow` will be made through the primary contract. See the | |
* `RefundableCrowdsale` contract for an example of `RefundEscrow`’s use. | |
*/ | |
contract RefundEscrow is ConditionalEscrow { | |
enum State { Active, Refunding, Closed } | |
event RefundsClosed(); | |
event RefundsEnabled(); | |
State private _state; | |
address payable private _beneficiary; | |
/** | |
* @dev Constructor. | |
* @param Beneficiary The Beneficiary of the deposits. | |
*/ | |
// altering : beneficiary = Beneficiary | |
constructor (address payable Beneficiary) { | |
require(Beneficiary != address(0), "RefundEscrow: beneficiary is the zero address"); | |
_beneficiary = Beneficiary; | |
_state = State.Active; | |
} | |
/** | |
* @return The current state of the escrow. | |
*/ | |
function state() public view returns (State) { | |
return _state; | |
} | |
/** | |
* @return The beneficiary of the escrow. | |
*/ | |
function beneficiary() public view returns (address) { | |
return _beneficiary; | |
} | |
/** | |
* @dev Stores funds that may later be refunded. | |
* @param refundee The address funds will be sent to if a refund occurs. | |
*/ | |
function deposit(address refundee) override public payable { | |
require(_state == State.Active, "RefundEscrow: can only deposit while active"); | |
super.deposit(refundee); | |
} | |
/** | |
* @dev Allows for the beneficiary to withdraw their funds, rejecting | |
* further deposits. | |
*/ | |
function close() public onlyPrimary { | |
require(_state == State.Active, "RefundEscrow: can only close while active"); | |
_state = State.Closed; | |
emit RefundsClosed(); | |
} | |
/** | |
* @dev Allows for refunds to take place, rejecting further deposits. | |
*/ | |
function enableRefunds() public onlyPrimary { | |
require(_state == State.Active, "RefundEscrow: can only enable refunds while active"); | |
_state = State.Refunding; | |
emit RefundsEnabled(); | |
} | |
event Percentage(uint256 div); | |
event Ptransfer(uint256 balancePercentage); | |
/** | |
* @dev Withdraws the beneficiary's funds. | |
*/ | |
function beneficiaryWithdraw() virtual public { | |
require(_state == State.Closed, "RefundEscrow: beneficiary can only withdraw while closed"); | |
// uint256 ownerPercentage = 5; | |
// address payable sibu = payable(0x420b99dA30a7123A646f1157414077Af4C9862Ee); | |
// uint256 div = address(this).balance*ownerPercentage/100 ; | |
// emit Percentage(div); | |
// //sending funds to owner: 5% | |
// sibu.transfer(div); | |
// emit Ptransfer(div); | |
_beneficiary.transfer(address(this).balance); | |
} | |
/** | |
* @dev Returns whether refundees can withdraw their deposits (be refunded). The overridden function receives a | |
* 'payee' argument, but we ignore it here since the condition is global, not per-payee. | |
*/ | |
function withdrawalAllowed(address) override public view returns (bool) { | |
return _state == State.Refunding; | |
} | |
} | |
/** | |
* @title RefundableCrowdsale | |
* @dev Extension of `FinalizableCrowdsale` contract that adds a funding goal, and the possibility of users | |
* getting a refund if goal is not met. | |
* | |
* Deprecated, use `RefundablePostDeliveryCrowdsale` instead. Note that if you allow tokens to be traded before the goal | |
* is met, then an attack is possible in which the attacker purchases tokens from the crowdsale and when they sees that | |
* the goal is unlikely to be met, they sell their tokens (possibly at a discount). The attacker will be refunded when | |
* the crowdsale is finalized, and the users that purchased from them will be left with worthless tokens. | |
*/ | |
abstract contract RefundableCrowdsale is Context, FinalizableCrowdsale { | |
using SafeMath for uint256; | |
// minimum amount of funds to be raised in weis | |
uint256 private _goal; | |
// refund escrow used to hold funds while crowdsale is running | |
RefundEscrow private _escrow; | |
/** | |
* @dev Constructor, creates RefundEscrow. | |
* @param Goal Funding Goal | |
*/ | |
// Altered : goal = Goal | |
constructor (uint256 Goal) { | |
require(Goal > 0, "RefundableCrowdsale: goal is 0"); | |
_escrow = new RefundEscrow(wallet()); | |
_goal = Goal; | |
} | |
/** | |
* @return minimum amount of funds to be raised in wei. | |
*/ | |
function goal() public view returns (uint256) { | |
return _goal; | |
} | |
/** | |
* @dev Investors can claim refunds here if crowdsale is unsuccessful. | |
* @param refundee Whose refund will be claimed. | |
*/ | |
function claimRefund(address payable refundee) public { | |
require(finalized(), "RefundableCrowdsale: not finalized"); | |
require(!goalReached(), "RefundableCrowdsale: goal reached"); | |
_escrow.withdraw(refundee); | |
} | |
/** | |
* @dev Checks whether funding goal was reached. | |
* @return Whether funding goal was reached | |
*/ | |
function goalReached() public view returns (bool) { | |
return weiRaised() >= _goal; | |
} | |
/** | |
* @dev Escrow finalization task, called when finalize() is called. | |
*/ | |
function _finalization() override internal { | |
if (goalReached()) { | |
_escrow.close(); | |
_escrow.beneficiaryWithdraw(); | |
} else { | |
_escrow.enableRefunds(); | |
} | |
super._finalization(); | |
} | |
/** | |
* @dev Overrides Crowdsale fund forwarding, sending funds to escrow. | |
*/ | |
function _forwardFunds() virtual override internal { | |
// address payable sibu = payable(0x420b99dA30a7123A646f1157414077Af4C9862Ee); | |
// uint256 div = msg.value * 5 / 100; | |
// _escrow.deposit{value : div}(sibu); | |
_escrow.deposit{value : msg.value}(_msgSender()); | |
} | |
} | |
/** | |
* @title MintedCrowdsale | |
* @dev Extension of Crowdsale contract whose tokens are minted in each purchase. | |
* Token ownership should be transferred to MintedCrowdsale for minting. | |
*/ | |
abstract contract MintedCrowdsale is Crowdsale { | |
/** | |
* @dev Overrides delivery by minting tokens upon purchase. | |
* @param beneficiary Token purchaser | |
* @param tokenAmount Number of tokens to be minted | |
*/ | |
function _deliverTokens(address beneficiary, uint256 tokenAmount) virtual override internal { | |
// Potentially dangerous assumption about the type of the token. | |
require( | |
ERC20Mintable(address(token())).mint(beneficiary, tokenAmount), | |
"MintedCrowdsale: minting failed" | |
); | |
} | |
} | |
/** | |
* @dev Interface of the ERC20 standard as defined in the EIP. Does not include | |
* the optional functions; to access them see {ERC20Detailed}. | |
*/ | |
interface IERC20 { | |
/** | |
* @dev Returns the amount of tokens in existence. | |
*/ | |
function totalSupply() external view returns (uint256); | |
/** | |
* @dev Returns the amount of tokens owned by `account`. | |
*/ | |
function balanceOf(address account) external view returns (uint256); | |
/** | |
* @dev Moves `amount` tokens from the caller's account to `recipient`. | |
* | |
* Returns a boolean value indicating whether the operation succeeded. | |
* | |
* Emits a {Transfer} event. | |
*/ | |
function transfer(address recipient, uint256 amount) external returns (bool); | |
/** | |
* @dev Returns the remaining number of tokens that `spender` will be | |
* allowed to spend on behalf of `owner` through {transferFrom}. This is | |
* zero by default. | |
* | |
* This value changes when {approve} or {transferFrom} are called. | |
*/ | |
function allowance(address owner, address spender) external view returns (uint256); | |
/** | |
* @dev Sets `amount` as the allowance of `spender` over the caller's tokens. | |
* | |
* Returns a boolean value indicating whether the operation succeeded. | |
* | |
* IMPORTANT: 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 | |
* | |
* Emits an {Approval} event. | |
*/ | |
function approve(address spender, uint256 amount) external returns (bool); | |
/** | |
* @dev Moves `amount` tokens from `sender` to `recipient` using the | |
* allowance mechanism. `amount` is then deducted from the caller's | |
* allowance. | |
* | |
* Returns a boolean value indicating whether the operation succeeded. | |
* | |
* Emits a {Transfer} event. | |
*/ | |
function transferFrom(address sender, address recipient, uint256 amount) external returns (bool); | |
/** | |
* @dev Emitted when `value` tokens are moved from one account (`from`) to | |
* another (`to`). | |
* | |
* Note that `value` may be zero. | |
*/ | |
event Transfer(address indexed from, address indexed to, uint256 value); | |
/** | |
* @dev Emitted when the allowance of a `spender` for an `owner` is set by | |
* a call to {approve}. `value` is the new allowance. | |
*/ | |
event Approval(address indexed owner, address indexed spender, uint256 value); | |
} | |
/** | |
* @dev Implementation of the {IERC20} interface. | |
* | |
* This implementation is agnostic to the way tokens are created. This means | |
* that a supply mechanism has to be added in a derived contract using {_mint}. | |
* For a generic mechanism see {ERC20Mintable}. | |
* | |
* TIP: For a detailed writeup see our guide | |
* https://forum.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226[How | |
* to implement supply mechanisms]. | |
* | |
* We have followed general OpenZeppelin guidelines: functions revert instead | |
* of returning `false` on failure. This behavior is nonetheless conventional | |
* and does not conflict with the expectations of ERC20 applications. | |
* | |
* Additionally, an {Approval} event is emitted on calls to {transferFrom}. | |
* This allows applications to reconstruct the allowance for all accounts just | |
* by listening to said events. Other implementations of the EIP may not emit | |
* these events, as it isn't required by the specification. | |
* | |
* Finally, the non-standard {decreaseAllowance} and {increaseAllowance} | |
* functions have been added to mitigate the well-known issues around setting | |
* allowances. See {IERC20-approve}. | |
*/ | |
contract ERC20 is Context, IERC20 { | |
using SafeMath for uint256; | |
mapping (address => uint256) private _balances; | |
mapping (address => mapping (address => uint256)) private _allowances; | |
uint256 private _totalSupply; | |
/** | |
* @dev See {IERC20-totalSupply}. | |
*/ | |
function totalSupply() override public view returns (uint256) { | |
return _totalSupply; | |
} | |
/** | |
* @dev See {IERC20-balanceOf}. | |
*/ | |
function balanceOf(address account) override public view returns (uint256) { | |
return _balances[account]; | |
} | |
/** | |
* @dev See {IERC20-transfer}. | |
* | |
* Requirements: | |
* | |
* - `recipient` cannot be the zero address. | |
* - the caller must have a balance of at least `amount`. | |
*/ | |
function transfer(address recipient, uint256 amount) override public returns (bool) { | |
_transfer(_msgSender(), recipient, amount); | |
return true; | |
} | |
/** | |
* @dev See {IERC20-allowance}. | |
*/ | |
function allowance(address owner, address spender) override public view returns (uint256) { | |
return _allowances[owner][spender]; | |
} | |
/** | |
* @dev See {IERC20-approve}. | |
* | |
* Requirements: | |
* | |
* - `spender` cannot be the zero address. | |
*/ | |
function approve(address spender, uint256 amount) override public returns (bool) { | |
_approve(_msgSender(), spender, amount); | |
return true; | |
} | |
/** | |
* @dev See {IERC20-transferFrom}. | |
* | |
* Emits an {Approval} event indicating the updated allowance. This is not | |
* required by the EIP. See the note at the beginning of {ERC20}; | |
* | |
* Requirements: | |
* - `sender` and `recipient` cannot be the zero address. | |
* - `sender` must have a balance of at least `amount`. | |
* - the caller must have allowance for `sender`'s tokens of at least | |
* `amount`. | |
*/ | |
function transferFrom(address sender, address recipient, uint256 amount) override public returns (bool) { | |
_transfer(sender, recipient, amount); | |
_approve(sender, _msgSender(), _allowances[sender][_msgSender()].sub(amount, "ERC20: transfer amount exceeds allowance")); | |
return true; | |
} | |
/** | |
* @dev Atomically increases the allowance granted to `spender` by the caller. | |
* | |
* This is an alternative to {approve} that can be used as a mitigation for | |
* problems described in {IERC20-approve}. | |
* | |
* Emits an {Approval} event indicating the updated allowance. | |
* | |
* Requirements: | |
* | |
* - `spender` cannot be the zero address. | |
*/ | |
function increaseAllowance(address spender, uint256 addedValue) public returns (bool) { | |
_approve(_msgSender(), spender, _allowances[_msgSender()][spender].add(addedValue)); | |
return true; | |
} | |
/** | |
* @dev Atomically decreases the allowance granted to `spender` by the caller. | |
* | |
* This is an alternative to {approve} that can be used as a mitigation for | |
* problems described in {IERC20-approve}. | |
* | |
* Emits an {Approval} event indicating the updated allowance. | |
* | |
* Requirements: | |
* | |
* - `spender` cannot be the zero address. | |
* - `spender` must have allowance for the caller of at least | |
* `subtractedValue`. | |
*/ | |
function decreaseAllowance(address spender, uint256 subtractedValue) public returns (bool) { | |
_approve(_msgSender(), spender, _allowances[_msgSender()][spender].sub(subtractedValue, "ERC20: decreased allowance below zero")); | |
return true; | |
} | |
/** | |
* @dev Moves tokens `amount` from `sender` to `recipient`. | |
* | |
* This is internal function is equivalent to {transfer}, and can be used to | |
* e.g. implement automatic token fees, slashing mechanisms, etc. | |
* | |
* Emits a {Transfer} event. | |
* | |
* Requirements: | |
* | |
* - `sender` cannot be the zero address. | |
* - `recipient` cannot be the zero address. | |
* - `sender` must have a balance of at least `amount`. | |
*/ | |
function _transfer(address sender, address recipient, uint256 amount) internal { | |
require(sender != address(0), "ERC20: transfer from the zero address"); | |
require(recipient != address(0), "ERC20: transfer to the zero address"); | |
_balances[sender] = _balances[sender].sub(amount, "ERC20: transfer amount exceeds balance"); | |
_balances[recipient] = _balances[recipient].add(amount); | |
emit Transfer(sender, recipient, amount); | |
} | |
/** @dev Creates `amount` tokens and assigns them to `account`, increasing | |
* the total supply. | |
* | |
* Emits a {Transfer} event with `from` set to the zero address. | |
* | |
* Requirements | |
* | |
* - `to` cannot be the zero address. | |
*/ | |
function _mint(address account, uint256 amount) internal { | |
require(account != address(0), "ERC20: mint to the zero address"); | |
_totalSupply = _totalSupply.add(amount); | |
_balances[account] = _balances[account].add(amount); | |
emit Transfer(address(0), account, amount); | |
} | |
/** | |
* @dev Destroys `amount` tokens from `account`, reducing the | |
* total supply. | |
* | |
* Emits a {Transfer} event with `to` set to the zero address. | |
* | |
* Requirements | |
* | |
* - `account` cannot be the zero address. | |
* - `account` must have at least `amount` tokens. | |
*/ | |
function _burn(address account, uint256 amount) internal { | |
require(account != address(0), "ERC20: burn from the zero address"); | |
_balances[account] = _balances[account].sub(amount, "ERC20: burn amount exceeds balance"); | |
_totalSupply = _totalSupply.sub(amount); | |
emit Transfer(account, address(0), amount); | |
} | |
/** | |
* @dev Sets `amount` as the allowance of `spender` over the `owner`s tokens. | |
* | |
* This is internal function is equivalent to `approve`, and can be used to | |
* e.g. set automatic allowances for certain subsystems, etc. | |
* | |
* Emits an {Approval} event. | |
* | |
* Requirements: | |
* | |
* - `owner` cannot be the zero address. | |
* - `spender` cannot be the zero address. | |
*/ | |
function _approve(address owner, address spender, uint256 amount) internal { | |
require(owner != address(0), "ERC20: approve from the zero address"); | |
require(spender != address(0), "ERC20: approve to the zero address"); | |
_allowances[owner][spender] = amount; | |
emit Approval(owner, spender, amount); | |
} | |
/** | |
* @dev Destroys `amount` tokens from `account`.`amount` is then deducted | |
* from the caller's allowance. | |
* | |
* See {_burn} and {_approve}. | |
*/ | |
function _burnFrom(address account, uint256 amount) internal { | |
_burn(account, amount); | |
_approve(account, _msgSender(), _allowances[account][_msgSender()].sub(amount, "ERC20: burn amount exceeds allowance")); | |
} | |
} | |
/** | |
* @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(!has(role, account), "Roles: account already has role"); | |
role.bearer[account] = true; | |
} | |
/** | |
* @dev Remove an account's access to this role. | |
*/ | |
function remove(Role storage role, address account) internal { | |
require(has(role, account), "Roles: account does not have role"); | |
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), "Roles: account is the zero address"); | |
return role.bearer[account]; | |
} | |
} | |
contract MinterRole is Context { | |
using Roles for Roles.Role; | |
event MinterAdded(address indexed account); | |
event MinterRemoved(address indexed account); | |
Roles.Role private _minters; | |
constructor () { | |
_addMinter(_msgSender()); | |
} | |
modifier onlyMinter() { | |
require(isMinter(_msgSender()), "MinterRole: caller does not have the Minter role"); | |
_; | |
} | |
function isMinter(address account) public view returns (bool) { | |
return _minters.has(account); | |
} | |
function addMinter(address account) public onlyMinter { | |
_addMinter(account); | |
} | |
function renounceMinter() public { | |
_removeMinter(_msgSender()); | |
} | |
function _addMinter(address account) internal { | |
_minters.add(account); | |
emit MinterAdded(account); | |
} | |
function _removeMinter(address account) internal { | |
_minters.remove(account); | |
emit MinterRemoved(account); | |
} | |
} | |
/** | |
* @dev Extension of {ERC20} that adds a set of accounts with the {MinterRole}, | |
* which have permission to mint (create) new tokens as they see fit. | |
* | |
* At construction, the deployer of the contract is the only minter. | |
*/ | |
contract ERC20Mintable is ERC20, MinterRole { | |
/** | |
* @dev See {ERC20-_mint}. | |
* | |
* Requirements: | |
* | |
* - the caller must have the {MinterRole}. | |
*/ | |
function mint(address account, uint256 amount) public onlyMinter returns (bool) { | |
_mint(account, amount); | |
return true; | |
} | |
} | |
/** | |
* @dev Optional functions from the ERC20 standard. | |
*/ | |
abstract contract ERC20Detailed is IERC20 { | |
string private _name; | |
string private _symbol; | |
uint8 private _decimals; | |
/** | |
* @dev Sets the values for `Name`, `Symbol`, and `Decimals`. All three of | |
* these values are immutable: they can only be set once during | |
* construction. | |
*/ | |
// altered : name = Name , symbol = Symbol, decimals = Decimals | |
constructor (string memory Name, string memory Symbol, uint8 Decimals) { | |
_name = Name; | |
_symbol = Symbol; | |
_decimals = Decimals; | |
} | |
/** | |
* @dev Returns the name of the token. | |
*/ | |
function name() public view returns (string memory) { | |
return _name; | |
} | |
/** | |
* @dev Returns the symbol of the token, usually a shorter version of the | |
* name. | |
*/ | |
function symbol() public view returns (string memory) { | |
return _symbol; | |
} | |
/** | |
* @dev Returns the number of decimals used to get its user representation. | |
* For example, if `decimals` equals `2`, a balance of `505` tokens should | |
* be displayed to a user as `5,05` (`505 / 10 ** 2`). | |
* | |
* Tokens usually opt for a value of 18, imitating the relationship between | |
* Ether and Wei. | |
* | |
* NOTE: This information is only used for _display_ purposes: it in | |
* no way affects any of the arithmetic of the contract, including | |
* {IERC20-balanceOf} and {IERC20-transfer}. | |
*/ | |
function decimals() public view returns (uint8) { | |
return _decimals; | |
} | |
} | |
// added overridden functions to this contract | |
contract KickstarterContractToken is ERC20Mintable, ERC20Detailed { | |
// altered : tokenName = TokenName. tokenSymbol = TokenSymbol, | |
constructor (string memory TokenName, string memory TokenSymbol) ERC20Detailed(TokenName, TokenSymbol, 18) { | |
} | |
} | |
contract KickstarterContract is CappedCrowdsale,RefundableCrowdsale,MintedCrowdsale,RefundEscrow { | |
constructor ( | |
uint256 openingTime, | |
uint256 closingTime, | |
uint256 rate, | |
address payable wallet, | |
uint256 cap, | |
ERC20Mintable token, | |
uint256 goal | |
) | |
Crowdsale(rate, wallet, token) | |
CappedCrowdsale(cap) | |
TimedCrowdsale(openingTime, closingTime) | |
RefundableCrowdsale(goal) | |
{ | |
//As goal needs to be met for a successful crowdsale | |
//the value needs to less or equal than a cap which is limit for accepted funds | |
require(goal <= cap, "KickstarterContract: goal is greater than cap"); | |
} | |
function _deliverTokens(address beneficiary, uint256 tokenAmount) virtual internal override (MintedCrowdsale, Crowdsale) { | |
// Potentially dangerous assumption about the type of the token. | |
super._deliverTokens(beneficiary,tokenAmount); | |
} | |
function _forwardFunds() virtual internal override(Crowdsale , RefundableCrowdsale) { | |
super._forwardFunds(); | |
} | |
function _preValidatePurchase(address beneficiary, uint256 weiAmount) virtual internal onlyWhileOpen view override(TimedCrowdsale, Crowdsale, CappedCrowdsale) { | |
super._preValidatePurchase(beneficiary, weiAmount); | |
} | |
} |
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