pragma solidity 0.6.12;
// SPDX-License-Identifier: MIT
/**
* @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.
*/
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.
*/
function div(
uint256 a,
uint256 b,
string memory errorMessage
) internal pure returns (uint256) {
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.
*/
function mod(
uint256 a,
uint256 b,
string memory errorMessage
) internal pure returns (uint256) {
require(b != 0, errorMessage);
return a % b;
}
function min(uint256 x, uint256 y) internal pure returns (uint256 z) {
z = x < y ? x : y;
}
// babylonian method (https://en.wikipedia.org/wiki/Methods_of_computing_square_roots#Babylonian_method)
function sqrt(uint256 y) internal pure returns (uint256 z) {
if (y > 3) {
z = y;
uint256 x = y / 2 + 1;
while (x < z) {
z = x;
x = (y / x + x) / 2;
}
} else if (y != 0) {
z = 1;
}
}
}
interface IBEP20 {
/**
* @dev Returns the amount of tokens in existence.
*/
function totalSupply() external view returns (uint256);
/**
* @dev Returns the token decimals.
*/
function decimals() external view returns (uint8);
/**
* @dev Returns the token symbol.
*/
function symbol() external view returns (string memory);
/**
* @dev Returns the token name.
*/
function name() external view returns (string memory);
/**
* @dev Returns the bep token owner.
*/
function getOwner() external view returns (address);
/**
* @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 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 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].
*/
function sendValue(address payable recipient, uint256 amount) internal {
require(address(this).balance >= amount, 'Address: insufficient balance');
// solhint-disable-next-line avoid-low-level-calls, avoid-call-value
(bool success, ) = recipient.call{value: amount}('');
require(success, 'Address: unable to send value, recipient may have reverted');
}
/**
* @dev Performs a Solidity function call using a low level `call`. A
* plain`call` is an unsafe replacement for a function call: use this
* function instead.
*
* If `target` reverts with a revert reason, it is bubbled up by this
* function (like regular Solidity function calls).
*
* Returns the raw returned data. To convert to the expected return value,
* use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
*
* Requirements:
*
* - `target` must be a contract.
* - calling `target` with `data` must not revert.
*
* _Available since v3.1._
*/
function functionCall(address target, bytes memory data) internal returns (bytes memory) {
return functionCall(target, data, 'Address: low-level call failed');
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
* `errorMessage` as a fallback revert reason when `target` reverts.
*
* _Available since v3.1._
*/
function functionCall(
address target,
bytes memory data,
string memory errorMessage
) internal returns (bytes memory) {
return _functionCallWithValue(target, data, 0, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but also transferring `value` wei to `target`.
*
* Requirements:
*
* - the calling contract must have an ETH balance of at least `value`.
* - the called Solidity function must be `payable`.
*
* _Available since v3.1._
*/
function functionCallWithValue(
address target,
bytes memory data,
uint256 value
) internal returns (bytes memory) {
return functionCallWithValue(target, data, value, 'Address: low-level call with value failed');
}
/**
* @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
* with `errorMessage` as a fallback revert reason when `target` reverts.
*
* _Available since v3.1._
*/
function functionCallWithValue(
address target,
bytes memory data,
uint256 value,
string memory errorMessage
) internal returns (bytes memory) {
require(address(this).balance >= value, 'Address: insufficient balance for call');
return _functionCallWithValue(target, data, value, errorMessage);
}
function _functionCallWithValue(
address target,
bytes memory data,
uint256 weiValue,
string memory errorMessage
) private returns (bytes memory) {
require(isContract(target), 'Address: call to non-contract');
// solhint-disable-next-line avoid-low-level-calls
(bool success, bytes memory returndata) = target.call{value: weiValue}(data);
if (success) {
return returndata;
} else {
// Look for revert reason and bubble it up if present
if (returndata.length > 0) {
// The easiest way to bubble the revert reason is using memory via assembly
// solhint-disable-next-line no-inline-assembly
assembly {
let returndata_size := mload(returndata)
revert(add(32, returndata), returndata_size)
}
} else {
revert(errorMessage);
}
}
}
}
/**
* @title SafeBEP20
* @dev Wrappers around BEP20 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 SafeBEP20 for IBEP20;` statement to your contract,
* which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
*/
library SafeBEP20 {
using SafeMath for uint256;
using Address for address;
function safeTransfer(
IBEP20 token,
address to,
uint256 value
) internal {
_callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
}
function safeTransferFrom(
IBEP20 token,
address from,
address to,
uint256 value
) internal {
_callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
}
/**
* @dev Deprecated. This function has issues similar to the ones found in
* {IBEP20-approve}, and its usage is discouraged.
*
* Whenever possible, use {safeIncreaseAllowance} and
* {safeDecreaseAllowance} instead.
*/
function safeApprove(
IBEP20 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),
'SafeBEP20: approve from non-zero to non-zero allowance'
);
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
}
function safeIncreaseAllowance(
IBEP20 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(
IBEP20 token,
address spender,
uint256 value
) internal {
uint256 newAllowance = token.allowance(address(this), spender).sub(
value,
'SafeBEP20: 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(IBEP20 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. We use {Address.functionCall} to perform this call, which verifies that
// the target address contains contract code and also asserts for success in the low-level call.
bytes memory returndata = address(token).functionCall(data, 'SafeBEP20: low-level call failed');
if (returndata.length > 0) {
// Return data is optional
// solhint-disable-next-line max-line-length
require(abi.decode(returndata, (bool)), 'SafeBEP20: BEP20 operation did not succeed');
}
}
}
/*
* @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() internal {}
function _msgSender() internal view returns (address payable) {
return 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;
}
}
/**
* @dev Contract module which provides a basic access control mechanism, where
* there is an account (an owner) that can be granted exclusive access to
* specific functions.
*
* By default, the owner account will be the one that deploys the contract. This
* can later be changed with {transferOwnership}.
*
* This module is used through inheritance. It will make available the modifier
* `onlyOwner`, which can be applied to your functions to restrict their use to
* the owner.
*/
contract Ownable is Context {
address private _owner;
event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
/**
* @dev Initializes the contract setting the deployer as the initial owner.
*/
constructor() internal {
address msgSender = _msgSender();
_owner = msgSender;
emit OwnershipTransferred(address(0), msgSender);
}
/**
* @dev Returns the address of the current owner.
*/
function owner() public view returns (address) {
return _owner;
}
/**
* @dev Throws if called by any account other than the owner.
*/
modifier onlyOwner() {
require(_owner == _msgSender(), 'Ownable: caller is not the owner');
_;
}
/**
* @dev Leaves the contract without owner. It will not be possible to call
* `onlyOwner` functions anymore. Can only be called by the current owner.
*
* NOTE: Renouncing ownership will leave the contract without an owner,
* thereby removing any functionality that is only available to the owner.
*/
function renounceOwnership() public onlyOwner {
emit OwnershipTransferred(_owner, address(0));
_owner = address(0);
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`).
* Can only be called by the current owner.
*/
function transferOwnership(address newOwner) public onlyOwner {
_transferOwnership(newOwner);
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`).
*/
function _transferOwnership(address newOwner) internal {
require(newOwner != address(0), 'Ownable: new owner is the zero address');
emit OwnershipTransferred(_owner, newOwner);
_owner = newOwner;
}
}
/**
* @dev Implementation of the {IBEP20} 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 {BEP20PresetMinterPauser}.
*
* TIP: For a detailed writeup see our guide
* https://forum.zeppelin.solutions/t/how-to-implement-BEP20-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 BEP20 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 {IBEP20-approve}.
*/
contract BEP20 is Context, IBEP20, Ownable {
using SafeMath for uint256;
using Address for address;
mapping(address => uint256) private _balances;
mapping(address => mapping(address => uint256)) private _allowances;
uint256 private _totalSupply;
string private _name;
string private _symbol;
uint8 private _decimals;
/**
* @dev Sets the values for {name} and {symbol}, initializes {decimals} with
* a default value of 18.
*
* To select a different value for {decimals}, use {_setupDecimals}.
*
* All three of these values are immutable: they can only be set once during
* construction.
*/
constructor(string memory name, string memory symbol) public {
_name = name;
_symbol = symbol;
_decimals = 18;
}
/**
* @dev Returns the bep token owner.
*/
function getOwner() external override view returns (address) {
return owner();
}
/**
* @dev Returns the token name.
*/
function name() public override view returns (string memory) {
return _name;
}
/**
* @dev Returns the token decimals.
*/
function decimals() public override view returns (uint8) {
return _decimals;
}
/**
* @dev Returns the token symbol.
*/
function symbol() public override view returns (string memory) {
return _symbol;
}
/**
* @dev See {BEP20-totalSupply}.
*/
function totalSupply() public override view returns (uint256) {
return _totalSupply;
}
/**
* @dev See {BEP20-balanceOf}.
*/
function balanceOf(address account) public override view returns (uint256) {
return _balances[account];
}
/**
* @dev See {BEP20-transfer}.
*
* Requirements:
*
* - `recipient` cannot be the zero address.
* - the caller must have a balance of at least `amount`.
*/
function transfer(address recipient, uint256 amount) public override returns (bool) {
_transfer(_msgSender(), recipient, amount);
return true;
}
/**
* @dev See {BEP20-allowance}.
*/
function allowance(address owner, address spender) public override view returns (uint256) {
return _allowances[owner][spender];
}
/**
* @dev See {BEP20-approve}.
*
* Requirements:
*
* - `spender` cannot be the zero address.
*/
function approve(address spender, uint256 amount) public override returns (bool) {
_approve(_msgSender(), spender, amount);
return true;
}
/**
* @dev See {BEP20-transferFrom}.
*
* Emits an {Approval} event indicating the updated allowance. This is not
* required by the EIP. See the note at the beginning of {BEP20};
*
* 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
) public override returns (bool) {
_transfer(sender, recipient, amount);
_approve(
sender,
_msgSender(),
_allowances[sender][_msgSender()].sub(amount, 'BEP20: 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 {BEP20-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 {BEP20-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, 'BEP20: decreased allowance below zero')
);
return true;
}
/**
* @dev Creates `amount` tokens and assigns them to `msg.sender`, increasing
* the total supply.
*
* Requirements
*
* - `msg.sender` must be the token owner
*/
function mint(uint256 amount) public onlyOwner returns (bool) {
_mint(_msgSender(), amount);
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), 'BEP20: transfer from the zero address');
require(recipient != address(0), 'BEP20: transfer to the zero address');
_balances[sender] = _balances[sender].sub(amount, 'BEP20: 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), 'BEP20: 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), 'BEP20: burn from the zero address');
_balances[account] = _balances[account].sub(amount, 'BEP20: 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), 'BEP20: approve from the zero address');
require(spender != address(0), 'BEP20: 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, 'BEP20: burn amount exceeds allowance')
);
}
}
// CakeToken with Governance.
contract CakeToken is BEP20('PancakeSwap Token', 'Cake') {
/// @notice Creates `_amount` token to `_to`. Must only be called by the owner (MasterChef).
function mint(address _to, uint256 _amount) public onlyOwner {
_mint(_to, _amount);
_moveDelegates(address(0), _delegates[_to], _amount);
}
// Copied and modified from YAM code:
// https://github.com/yam-finance/yam-protocol/blob/master/contracts/token/YAMGovernanceStorage.sol
// https://github.com/yam-finance/yam-protocol/blob/master/contracts/token/YAMGovernance.sol
// Which is copied and modified from COMPOUND:
// https://github.com/compound-finance/compound-protocol/blob/master/contracts/Governance/Comp.sol
/// @notice A record of each accounts delegate
mapping (address => address) internal _delegates;
/// @notice A checkpoint for marking number of votes from a given block
struct Checkpoint {
uint32 fromBlock;
uint256 votes;
}
/// @notice A record of votes checkpoints for each account, by index
mapping (address => mapping (uint32 => Checkpoint)) public checkpoints;
/// @notice The number of checkpoints for each account
mapping (address => uint32) public numCheckpoints;
/// @notice The EIP-712 typehash for the contract's domain
bytes32 public constant DOMAIN_TYPEHASH = keccak256("EIP712Domain(string name,uint256 chainId,address verifyingContract)");
/// @notice The EIP-712 typehash for the delegation struct used by the contract
bytes32 public constant DELEGATION_TYPEHASH = keccak256("Delegation(address delegatee,uint256 nonce,uint256 expiry)");
/// @notice A record of states for signing / validating signatures
mapping (address => uint) public nonces;
/// @notice An event thats emitted when an account changes its delegate
event DelegateChanged(address indexed delegator, address indexed fromDelegate, address indexed toDelegate);
/// @notice An event thats emitted when a delegate account's vote balance changes
event DelegateVotesChanged(address indexed delegate, uint previousBalance, uint newBalance);
/**
* @notice Delegate votes from `msg.sender` to `delegatee`
* @param delegator The address to get delegatee for
*/
function delegates(address delegator)
external
view
returns (address)
{
return _delegates[delegator];
}
/**
* @notice Delegate votes from `msg.sender` to `delegatee`
* @param delegatee The address to delegate votes to
*/
function delegate(address delegatee) external {
return _delegate(msg.sender, delegatee);
}
/**
* @notice Delegates votes from signatory to `delegatee`
* @param delegatee The address to delegate votes to
* @param nonce The contract state required to match the signature
* @param expiry The time at which to expire the signature
* @param v The recovery byte of the signature
* @param r Half of the ECDSA signature pair
* @param s Half of the ECDSA signature pair
*/
function delegateBySig(
address delegatee,
uint nonce,
uint expiry,
uint8 v,
bytes32 r,
bytes32 s
)
external
{
bytes32 domainSeparator = keccak256(
abi.encode(
DOMAIN_TYPEHASH,
keccak256(bytes(name())),
getChainId(),
address(this)
)
);
bytes32 structHash = keccak256(
abi.encode(
DELEGATION_TYPEHASH,
delegatee,
nonce,
expiry
)
);
bytes32 digest = keccak256(
abi.encodePacked(
"\x19\x01",
domainSeparator,
structHash
)
);
address signatory = ecrecover(digest, v, r, s);
require(signatory != address(0), "CAKE::delegateBySig: invalid signature");
require(nonce == nonces[signatory]++, "CAKE::delegateBySig: invalid nonce");
require(now <= expiry, "CAKE::delegateBySig: signature expired");
return _delegate(signatory, delegatee);
}
/**
* @notice Gets the current votes balance for `account`
* @param account The address to get votes balance
* @return The number of current votes for `account`
*/
function getCurrentVotes(address account)
external
view
returns (uint256)
{
uint32 nCheckpoints = numCheckpoints[account];
return nCheckpoints > 0 ? checkpoints[account][nCheckpoints - 1].votes : 0;
}
/**
* @notice Determine the prior number of votes for an account as of a block number
* @dev Block number must be a finalized block or else this function will revert to prevent misinformation.
* @param account The address of the account to check
* @param blockNumber The block number to get the vote balance at
* @return The number of votes the account had as of the given block
*/
function getPriorVotes(address account, uint blockNumber)
external
view
returns (uint256)
{
require(blockNumber < block.number, "CAKE::getPriorVotes: not yet determined");
uint32 nCheckpoints = numCheckpoints[account];
if (nCheckpoints == 0) {
return 0;
}
// First check most recent balance
if (checkpoints[account][nCheckpoints - 1].fromBlock <= blockNumber) {
return checkpoints[account][nCheckpoints - 1].votes;
}
// Next check implicit zero balance
if (checkpoints[account][0].fromBlock > blockNumber) {
return 0;
}
uint32 lower = 0;
uint32 upper = nCheckpoints - 1;
while (upper > lower) {
uint32 center = upper - (upper - lower) / 2; // ceil, avoiding overflow
Checkpoint memory cp = checkpoints[account][center];
if (cp.fromBlock == blockNumber) {
return cp.votes;
} else if (cp.fromBlock < blockNumber) {
lower = center;
} else {
upper = center - 1;
}
}
return checkpoints[account][lower].votes;
}
function _delegate(address delegator, address delegatee)
internal
{
address currentDelegate = _delegates[delegator];
uint256 delegatorBalance = balanceOf(delegator); // balance of underlying CAKEs (not scaled);
_delegates[delegator] = delegatee;
emit DelegateChanged(delegator, currentDelegate, delegatee);
_moveDelegates(currentDelegate, delegatee, delegatorBalance);
}
function _moveDelegates(address srcRep, address dstRep, uint256 amount) internal {
if (srcRep != dstRep && amount > 0) {
if (srcRep != address(0)) {
// decrease old representative
uint32 srcRepNum = numCheckpoints[srcRep];
uint256 srcRepOld = srcRepNum > 0 ? checkpoints[srcRep][srcRepNum - 1].votes : 0;
uint256 srcRepNew = srcRepOld.sub(amount);
_writeCheckpoint(srcRep, srcRepNum, srcRepOld, srcRepNew);
}
if (dstRep != address(0)) {
// increase new representative
uint32 dstRepNum = numCheckpoints[dstRep];
uint256 dstRepOld = dstRepNum > 0 ? checkpoints[dstRep][dstRepNum - 1].votes : 0;
uint256 dstRepNew = dstRepOld.add(amount);
_writeCheckpoint(dstRep, dstRepNum, dstRepOld, dstRepNew);
}
}
}
function _writeCheckpoint(
address delegatee,
uint32 nCheckpoints,
uint256 oldVotes,
uint256 newVotes
)
internal
{
uint32 blockNumber = safe32(block.number, "CAKE::_writeCheckpoint: block number exceeds 32 bits");
if (nCheckpoints > 0 && checkpoints[delegatee][nCheckpoints - 1].fromBlock == blockNumber) {
checkpoints[delegatee][nCheckpoints - 1].votes = newVotes;
} else {
checkpoints[delegatee][nCheckpoints] = Checkpoint(blockNumber, newVotes);
numCheckpoints[delegatee] = nCheckpoints + 1;
}
emit DelegateVotesChanged(delegatee, oldVotes, newVotes);
}
function safe32(uint n, string memory errorMessage) internal pure returns (uint32) {
require(n < 2**32, errorMessage);
return uint32(n);
}
function getChainId() internal pure returns (uint) {
uint256 chainId;
assembly { chainId := chainid() }
return chainId;
}
}
// SyrupBar with Governance.
contract SyrupBar is BEP20('SyrupBar Token', 'SYRUP') {
/// @notice Creates `_amount` token to `_to`. Must only be called by the owner (MasterChef).
function mint(address _to, uint256 _amount) public onlyOwner {
_mint(_to, _amount);
_moveDelegates(address(0), _delegates[_to], _amount);
}
function burn(address _from ,uint256 _amount) public onlyOwner {
_burn(_from, _amount);
_moveDelegates(_delegates[_from], address(0), _amount);
}
// The CAKE TOKEN!
CakeToken public cake;
constructor(
CakeToken _cake
) public {
cake = _cake;
}
// Safe cake transfer function, just in case if rounding error causes pool to not have enough CAKEs.
function safeCakeTransfer(address _to, uint256 _amount) public onlyOwner {
uint256 cakeBal = cake.balanceOf(address(this));
if (_amount > cakeBal) {
cake.transfer(_to, cakeBal);
} else {
cake.transfer(_to, _amount);
}
}
// Copied and modified from YAM code:
// https://github.com/yam-finance/yam-protocol/blob/master/contracts/token/YAMGovernanceStorage.sol
// https://github.com/yam-finance/yam-protocol/blob/master/contracts/token/YAMGovernance.sol
// Which is copied and modified from COMPOUND:
// https://github.com/compound-finance/compound-protocol/blob/master/contracts/Governance/Comp.sol
/// @notice A record of each accounts delegate
mapping (address => address) internal _delegates;
/// @notice A checkpoint for marking number of votes from a given block
struct Checkpoint {
uint32 fromBlock;
uint256 votes;
}
/// @notice A record of votes checkpoints for each account, by index
mapping (address => mapping (uint32 => Checkpoint)) public checkpoints;
/// @notice The number of checkpoints for each account
mapping (address => uint32) public numCheckpoints;
/// @notice The EIP-712 typehash for the contract's domain
bytes32 public constant DOMAIN_TYPEHASH = keccak256("EIP712Domain(string name,uint256 chainId,address verifyingContract)");
/// @notice The EIP-712 typehash for the delegation struct used by the contract
bytes32 public constant DELEGATION_TYPEHASH = keccak256("Delegation(address delegatee,uint256 nonce,uint256 expiry)");
/// @notice A record of states for signing / validating signatures
mapping (address => uint) public nonces;
/// @notice An event thats emitted when an account changes its delegate
event DelegateChanged(address indexed delegator, address indexed fromDelegate, address indexed toDelegate);
/// @notice An event thats emitted when a delegate account's vote balance changes
event DelegateVotesChanged(address indexed delegate, uint previousBalance, uint newBalance);
/**
* @notice Delegate votes from `msg.sender` to `delegatee`
* @param delegator The address to get delegatee for
*/
function delegates(address delegator)
external
view
returns (address)
{
return _delegates[delegator];
}
/**
* @notice Delegate votes from `msg.sender` to `delegatee`
* @param delegatee The address to delegate votes to
*/
function delegate(address delegatee) external {
return _delegate(msg.sender, delegatee);
}
/**
* @notice Delegates votes from signatory to `delegatee`
* @param delegatee The address to delegate votes to
* @param nonce The contract state required to match the signature
* @param expiry The time at which to expire the signature
* @param v The recovery byte of the signature
* @param r Half of the ECDSA signature pair
* @param s Half of the ECDSA signature pair
*/
function delegateBySig(
address delegatee,
uint nonce,
uint expiry,
uint8 v,
bytes32 r,
bytes32 s
)
external
{
bytes32 domainSeparator = keccak256(
abi.encode(
DOMAIN_TYPEHASH,
keccak256(bytes(name())),
getChainId(),
address(this)
)
);
bytes32 structHash = keccak256(
abi.encode(
DELEGATION_TYPEHASH,
delegatee,
nonce,
expiry
)
);
bytes32 digest = keccak256(
abi.encodePacked(
"\x19\x01",
domainSeparator,
structHash
)
);
address signatory = ecrecover(digest, v, r, s);
require(signatory != address(0), "CAKE::delegateBySig: invalid signature");
require(nonce == nonces[signatory]++, "CAKE::delegateBySig: invalid nonce");
require(now <= expiry, "CAKE::delegateBySig: signature expired");
return _delegate(signatory, delegatee);
}
/**
* @notice Gets the current votes balance for `account`
* @param account The address to get votes balance
* @return The number of current votes for `account`
*/
function getCurrentVotes(address account)
external
view
returns (uint256)
{
uint32 nCheckpoints = numCheckpoints[account];
return nCheckpoints > 0 ? checkpoints[account][nCheckpoints - 1].votes : 0;
}
/**
* @notice Determine the prior number of votes for an account as of a block number
* @dev Block number must be a finalized block or else this function will revert to prevent misinformation.
* @param account The address of the account to check
* @param blockNumber The block number to get the vote balance at
* @return The number of votes the account had as of the given block
*/
function getPriorVotes(address account, uint blockNumber)
external
view
returns (uint256)
{
require(blockNumber < block.number, "CAKE::getPriorVotes: not yet determined");
uint32 nCheckpoints = numCheckpoints[account];
if (nCheckpoints == 0) {
return 0;
}
// First check most recent balance
if (checkpoints[account][nCheckpoints - 1].fromBlock <= blockNumber) {
return checkpoints[account][nCheckpoints - 1].votes;
}
// Next check implicit zero balance
if (checkpoints[account][0].fromBlock > blockNumber) {
return 0;
}
uint32 lower = 0;
uint32 upper = nCheckpoints - 1;
while (upper > lower) {
uint32 center = upper - (upper - lower) / 2; // ceil, avoiding overflow
Checkpoint memory cp = checkpoints[account][center];
if (cp.fromBlock == blockNumber) {
return cp.votes;
} else if (cp.fromBlock < blockNumber) {
lower = center;
} else {
upper = center - 1;
}
}
return checkpoints[account][lower].votes;
}
function _delegate(address delegator, address delegatee)
internal
{
address currentDelegate = _delegates[delegator];
uint256 delegatorBalance = balanceOf(delegator); // balance of underlying CAKEs (not scaled);
_delegates[delegator] = delegatee;
emit DelegateChanged(delegator, currentDelegate, delegatee);
_moveDelegates(currentDelegate, delegatee, delegatorBalance);
}
function _moveDelegates(address srcRep, address dstRep, uint256 amount) internal {
if (srcRep != dstRep && amount > 0) {
if (srcRep != address(0)) {
// decrease old representative
uint32 srcRepNum = numCheckpoints[srcRep];
uint256 srcRepOld = srcRepNum > 0 ? checkpoints[srcRep][srcRepNum - 1].votes : 0;
uint256 srcRepNew = srcRepOld.sub(amount);
_writeCheckpoint(srcRep, srcRepNum, srcRepOld, srcRepNew);
}
if (dstRep != address(0)) {
// increase new representative
uint32 dstRepNum = numCheckpoints[dstRep];
uint256 dstRepOld = dstRepNum > 0 ? checkpoints[dstRep][dstRepNum - 1].votes : 0;
uint256 dstRepNew = dstRepOld.add(amount);
_writeCheckpoint(dstRep, dstRepNum, dstRepOld, dstRepNew);
}
}
}
function _writeCheckpoint(
address delegatee,
uint32 nCheckpoints,
uint256 oldVotes,
uint256 newVotes
)
internal
{
uint32 blockNumber = safe32(block.number, "CAKE::_writeCheckpoint: block number exceeds 32 bits");
if (nCheckpoints > 0 && checkpoints[delegatee][nCheckpoints - 1].fromBlock == blockNumber) {
checkpoints[delegatee][nCheckpoints - 1].votes = newVotes;
} else {
checkpoints[delegatee][nCheckpoints] = Checkpoint(blockNumber, newVotes);
numCheckpoints[delegatee] = nCheckpoints + 1;
}
emit DelegateVotesChanged(delegatee, oldVotes, newVotes);
}
function safe32(uint n, string memory errorMessage) internal pure returns (uint32) {
require(n < 2**32, errorMessage);
return uint32(n);
}
function getChainId() internal pure returns (uint) {
uint256 chainId;
assembly { chainId := chainid() }
return chainId;
}
}
// MasterChef is the master of Cake. He can make Cake and he is a fair guy.
//
// Note that it's ownable and the owner wields tremendous power. The ownership
// will be transferred to a governance smart contract once CAKE is sufficiently
// distributed and the community can show to govern itself.
//
// Have fun reading it. Hopefully it's bug-free. God bless.
contract MasterChef is Ownable {
using SafeMath for uint256;
using SafeBEP20 for IBEP20;
// Info of each user.
struct UserInfo {
uint256 amount; // How many LP tokens the user has provided.
uint256 rewardDebt; // Reward debt. See explanation below.
//
// We do some fancy math here. Basically, any point in time, the amount of CAKEs
// entitled to a user but is pending to be distributed is:
//
// pending reward = (user.amount * pool.accCakePerShare) - user.rewardDebt
//
// Whenever a user deposits or withdraws LP tokens to a pool. Here's what happens:
// 1. The pool's `accCakePerShare` (and `lastRewardBlock`) gets updated.
// 2. User receives the pending reward sent to his/her address.
// 3. User's `amount` gets updated.
// 4. User's `rewardDebt` gets updated.
}
// Info of each pool.
struct PoolInfo {
IBEP20 lpToken; // Address of LP token contract.
uint256 allocPoint; // How many allocation points assigned to this pool. CAKEs to distribute per block.
uint256 lastRewardBlock; // Last block number that CAKEs distribution occurs.
uint256 accCakePerShare; // Accumulated CAKEs per share, times 1e12. See below.
}
// The CAKE TOKEN!
CakeToken public cake;
// The SYRUP TOKEN!
SyrupBar public syrup;
// Dev address.
address public devaddr;
// CAKE tokens created per block.
uint256 public cakePerBlock;
// Bonus muliplier for early cake makers.
uint256 public BONUS_MULTIPLIER = 1;
// Info of each pool.
PoolInfo[] public poolInfo;
// Info of each user that stakes LP tokens.
mapping (uint256 => mapping (address => UserInfo)) public userInfo;
// Total allocation points. Must be the sum of all allocation points in all pools.
uint256 public totalAllocPoint = 0;
// The block number when CAKE mining starts.
uint256 public startBlock;
event Deposit(address indexed user, uint256 indexed pid, uint256 amount);
event Withdraw(address indexed user, uint256 indexed pid, uint256 amount);
event EmergencyWithdraw(address indexed user, uint256 indexed pid, uint256 amount);
constructor(
CakeToken _cake,
SyrupBar _syrup,
address _devaddr,
uint256 _cakePerBlock,
uint256 _startBlock
) public {
cake = _cake;
syrup = _syrup;
devaddr = _devaddr;
cakePerBlock = _cakePerBlock;
startBlock = _startBlock;
// staking pool
poolInfo.push(PoolInfo({
lpToken: _cake,
allocPoint: 1000,
lastRewardBlock: startBlock,
accCakePerShare: 0
}));
totalAllocPoint = 1000;
}
function updateMultiplier(uint256 multiplierNumber) public onlyOwner {
BONUS_MULTIPLIER = multiplierNumber;
}
function poolLength() external view returns (uint256) {
return poolInfo.length;
}
// Add a new lp to the pool. Can only be called by the owner.
// XXX DO NOT add the same LP token more than once. Rewards will be messed up if you do.
function add(uint256 _allocPoint, IBEP20 _lpToken, bool _withUpdate) public onlyOwner {
if (_withUpdate) {
massUpdatePools();
}
uint256 lastRewardBlock = block.number > startBlock ? block.number : startBlock;
totalAllocPoint = totalAllocPoint.add(_allocPoint);
poolInfo.push(PoolInfo({
lpToken: _lpToken,
allocPoint: _allocPoint,
lastRewardBlock: lastRewardBlock,
accCakePerShare: 0
}));
updateStakingPool();
}
// Update the given pool's CAKE allocation point. Can only be called by the owner.
function set(uint256 _pid, uint256 _allocPoint, bool _withUpdate) public onlyOwner {
if (_withUpdate) {
massUpdatePools();
}
uint256 prevAllocPoint = poolInfo[_pid].allocPoint;
poolInfo[_pid].allocPoint = _allocPoint;
if (prevAllocPoint != _allocPoint) {
totalAllocPoint = totalAllocPoint.sub(prevAllocPoint).add(_allocPoint);
updateStakingPool();
}
}
function updateStakingPool() internal {
uint256 length = poolInfo.length;
uint256 points = 0;
for (uint256 pid = 1; pid < length; ++pid) {
points = points.add(poolInfo[pid].allocPoint);
}
if (points != 0) {
points = points.div(3);
totalAllocPoint = totalAllocPoint.sub(poolInfo[0].allocPoint).add(points);
poolInfo[0].allocPoint = points;
}
}
// Return reward multiplier over the given _from to _to block.
function getMultiplier(uint256 _from, uint256 _to) public view returns (uint256) {
return _to.sub(_from).mul(BONUS_MULTIPLIER);
}
// View function to see pending CAKEs on frontend.
function pendingCake(uint256 _pid, address _user) external view returns (uint256) {
PoolInfo storage pool = poolInfo[_pid];
UserInfo storage user = userInfo[_pid][_user];
uint256 accCakePerShare = pool.accCakePerShare;
uint256 lpSupply = pool.lpToken.balanceOf(address(this));
if (block.number > pool.lastRewardBlock && lpSupply != 0) {
uint256 multiplier = getMultiplier(pool.lastRewardBlock, block.number);
uint256 cakeReward = multiplier.mul(cakePerBlock).mul(pool.allocPoint).div(totalAllocPoint);
accCakePerShare = accCakePerShare.add(cakeReward.mul(1e12).div(lpSupply));
}
return user.amount.mul(accCakePerShare).div(1e12).sub(user.rewardDebt);
}
// Update reward variables for all pools. Be careful of gas spending!
function massUpdatePools() public {
uint256 length = poolInfo.length;
for (uint256 pid = 0; pid < length; ++pid) {
updatePool(pid);
}
}
// Update reward variables of the given pool to be up-to-date.
function updatePool(uint256 _pid) public {
PoolInfo storage pool = poolInfo[_pid];
if (block.number <= pool.lastRewardBlock) {
return;
}
uint256 lpSupply = pool.lpToken.balanceOf(address(this));
if (lpSupply == 0) {
pool.lastRewardBlock = block.number;
return;
}
uint256 multiplier = getMultiplier(pool.lastRewardBlock, block.number);
uint256 cakeReward = multiplier.mul(cakePerBlock).mul(pool.allocPoint).div(totalAllocPoint);
cake.mint(devaddr, cakeReward.div(10));
cake.mint(address(syrup), cakeReward);
pool.accCakePerShare = pool.accCakePerShare.add(cakeReward.mul(1e12).div(lpSupply));
pool.lastRewardBlock = block.number;
}
// Deposit LP tokens to MasterChef for CAKE allocation.
function deposit(uint256 _pid, uint256 _amount) public {
require (_pid != 0, 'deposit CAKE by staking');
PoolInfo storage pool = poolInfo[_pid];
UserInfo storage user = userInfo[_pid][msg.sender];
updatePool(_pid);
if (user.amount > 0) {
uint256 pending = user.amount.mul(pool.accCakePerShare).div(1e12).sub(user.rewardDebt);
if(pending > 0) {
safeCakeTransfer(msg.sender, pending);
}
}
if (_amount > 0) {
pool.lpToken.safeTransferFrom(address(msg.sender), address(this), _amount);
user.amount = user.amount.add(_amount);
}
user.rewardDebt = user.amount.mul(pool.accCakePerShare).div(1e12);
emit Deposit(msg.sender, _pid, _amount);
}
// Withdraw LP tokens from MasterChef.
function withdraw(uint256 _pid, uint256 _amount) public {
require (_pid != 0, 'withdraw CAKE by unstaking');
PoolInfo storage pool = poolInfo[_pid];
UserInfo storage user = userInfo[_pid][msg.sender];
require(user.amount >= _amount, "withdraw: not good");
updatePool(_pid);
uint256 pending = user.amount.mul(pool.accCakePerShare).div(1e12).sub(user.rewardDebt);
if(pending > 0) {
safeCakeTransfer(msg.sender, pending);
}
if(_amount > 0) {
user.amount = user.amount.sub(_amount);
pool.lpToken.safeTransfer(address(msg.sender), _amount);
}
user.rewardDebt = user.amount.mul(pool.accCakePerShare).div(1e12);
emit Withdraw(msg.sender, _pid, _amount);
}
// Stake CAKE tokens to MasterChef
function enterStaking(uint256 _amount) public {
PoolInfo storage pool = poolInfo[0];
UserInfo storage user = userInfo[0][msg.sender];
updatePool(0);
if (user.amount > 0) {
uint256 pending = user.amount.mul(pool.accCakePerShare).div(1e12).sub(user.rewardDebt);
if(pending > 0) {
safeCakeTransfer(msg.sender, pending);
}
}
if(_amount > 0) {
pool.lpToken.safeTransferFrom(address(msg.sender), address(this), _amount);
user.amount = user.amount.add(_amount);
}
user.rewardDebt = user.amount.mul(pool.accCakePerShare).div(1e12);
syrup.mint(msg.sender, _amount);
emit Deposit(msg.sender, 0, _amount);
}
// Withdraw CAKE tokens from STAKING.
function leaveStaking(uint256 _amount) public {
PoolInfo storage pool = poolInfo[0];
UserInfo storage user = userInfo[0][msg.sender];
require(user.amount >= _amount, "withdraw: not good");
updatePool(0);
uint256 pending = user.amount.mul(pool.accCakePerShare).div(1e12).sub(user.rewardDebt);
if(pending > 0) {
safeCakeTransfer(msg.sender, pending);
}
if(_amount > 0) {
user.amount = user.amount.sub(_amount);
pool.lpToken.safeTransfer(address(msg.sender), _amount);
}
user.rewardDebt = user.amount.mul(pool.accCakePerShare).div(1e12);
syrup.burn(msg.sender, _amount);
emit Withdraw(msg.sender, 0, _amount);
}
// Withdraw without caring about rewards. EMERGENCY ONLY.
function emergencyWithdraw(uint256 _pid) public {
PoolInfo storage pool = poolInfo[_pid];
UserInfo storage user = userInfo[_pid][msg.sender];
pool.lpToken.safeTransfer(address(msg.sender), user.amount);
emit EmergencyWithdraw(msg.sender, _pid, user.amount);
user.amount = 0;
user.rewardDebt = 0;
}
// Safe cake transfer function, just in case if rounding error causes pool to not have enough CAKEs.
function safeCakeTransfer(address _to, uint256 _amount) internal {
syrup.safeCakeTransfer(_to, _amount);
}
// Update dev address by the previous dev.
function dev(address _devaddr) public {
require(msg.sender == devaddr, "dev: wut?");
devaddr = _devaddr;
}
}
