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// SPDX-License-Identifier: MIT | |
// OpenZeppelin Contracts (last updated v4.9.0) (access/Ownable.sol) | |
pragma solidity ^0.8.0; | |
import "../utils/Context.sol"; | |
/** | |
* @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. | |
*/ | |
abstract 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() { | |
_transferOwnership(_msgSender()); | |
} | |
/** | |
* @dev Throws if called by any account other than the owner. | |
*/ | |
modifier onlyOwner() { | |
_checkOwner(); | |
_; | |
} | |
/** | |
* @dev Returns the address of the current owner. | |
*/ | |
function owner() public view virtual returns (address) { | |
return _owner; | |
} | |
/** | |
* @dev Throws if the sender is not the owner. | |
*/ | |
function _checkOwner() internal view virtual { | |
require(owner() == _msgSender(), "Ownable: caller is not the owner"); | |
} | |
/** | |
* @dev Leaves the contract without owner. It will not be possible to call | |
* `onlyOwner` functions. Can only be called by the current owner. | |
* | |
* NOTE: Renouncing ownership will leave the contract without an owner, | |
* thereby disabling any functionality that is only available to the owner. | |
*/ | |
function renounceOwnership() public virtual onlyOwner { | |
_transferOwnership(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 virtual onlyOwner { | |
require(newOwner != address(0), "Ownable: new owner is the zero address"); | |
_transferOwnership(newOwner); | |
} | |
/** | |
* @dev Transfers ownership of the contract to a new account (`newOwner`). | |
* Internal function without access restriction. | |
*/ | |
function _transferOwnership(address newOwner) internal virtual { | |
address oldOwner = _owner; | |
_owner = newOwner; | |
emit OwnershipTransferred(oldOwner, newOwner); | |
} | |
} |
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// SPDX-License-Identifier: MIT | |
// OpenZeppelin Contracts (last updated v4.9.0) (proxy/utils/Initializable.sol) | |
pragma solidity ^0.8.2; | |
import "../../utils/Address.sol"; | |
/** | |
* @dev This is a base contract to aid in writing upgradeable contracts, or any kind of contract that will be deployed | |
* behind a proxy. Since proxied contracts do not make use of a constructor, it's common to move constructor logic to an | |
* external initializer function, usually called `initialize`. It then becomes necessary to protect this initializer | |
* function so it can only be called once. The {initializer} modifier provided by this contract will have this effect. | |
* | |
* The initialization functions use a version number. Once a version number is used, it is consumed and cannot be | |
* reused. This mechanism prevents re-execution of each "step" but allows the creation of new initialization steps in | |
* case an upgrade adds a module that needs to be initialized. | |
* | |
* For example: | |
* | |
* [.hljs-theme-light.nopadding] | |
* ```solidity | |
* contract MyToken is ERC20Upgradeable { | |
* function initialize() initializer public { | |
* __ERC20_init("MyToken", "MTK"); | |
* } | |
* } | |
* | |
* contract MyTokenV2 is MyToken, ERC20PermitUpgradeable { | |
* function initializeV2() reinitializer(2) public { | |
* __ERC20Permit_init("MyToken"); | |
* } | |
* } | |
* ``` | |
* | |
* TIP: To avoid leaving the proxy in an uninitialized state, the initializer function should be called as early as | |
* possible by providing the encoded function call as the `_data` argument to {ERC1967Proxy-constructor}. | |
* | |
* CAUTION: When used with inheritance, manual care must be taken to not invoke a parent initializer twice, or to ensure | |
* that all initializers are idempotent. This is not verified automatically as constructors are by Solidity. | |
* | |
* [CAUTION] | |
* ==== | |
* Avoid leaving a contract uninitialized. | |
* | |
* An uninitialized contract can be taken over by an attacker. This applies to both a proxy and its implementation | |
* contract, which may impact the proxy. To prevent the implementation contract from being used, you should invoke | |
* the {_disableInitializers} function in the constructor to automatically lock it when it is deployed: | |
* | |
* [.hljs-theme-light.nopadding] | |
* ``` | |
* /// @custom:oz-upgrades-unsafe-allow constructor | |
* constructor() { | |
* _disableInitializers(); | |
* } | |
* ``` | |
* ==== | |
*/ | |
abstract contract Initializable { | |
/** | |
* @dev Indicates that the contract has been initialized. | |
* @custom:oz-retyped-from bool | |
*/ | |
uint8 private _initialized; | |
/** | |
* @dev Indicates that the contract is in the process of being initialized. | |
*/ | |
bool private _initializing; | |
/** | |
* @dev Triggered when the contract has been initialized or reinitialized. | |
*/ | |
event Initialized(uint8 version); | |
/** | |
* @dev A modifier that defines a protected initializer function that can be invoked at most once. In its scope, | |
* `onlyInitializing` functions can be used to initialize parent contracts. | |
* | |
* Similar to `reinitializer(1)`, except that functions marked with `initializer` can be nested in the context of a | |
* constructor. | |
* | |
* Emits an {Initialized} event. | |
*/ | |
modifier initializer() { | |
bool isTopLevelCall = !_initializing; | |
require( | |
(isTopLevelCall && _initialized < 1) || (!Address.isContract(address(this)) && _initialized == 1), | |
"Initializable: contract is already initialized" | |
); | |
_initialized = 1; | |
if (isTopLevelCall) { | |
_initializing = true; | |
} | |
_; | |
if (isTopLevelCall) { | |
_initializing = false; | |
emit Initialized(1); | |
} | |
} | |
/** | |
* @dev A modifier that defines a protected reinitializer function that can be invoked at most once, and only if the | |
* contract hasn't been initialized to a greater version before. In its scope, `onlyInitializing` functions can be | |
* used to initialize parent contracts. | |
* | |
* A reinitializer may be used after the original initialization step. This is essential to configure modules that | |
* are added through upgrades and that require initialization. | |
* | |
* When `version` is 1, this modifier is similar to `initializer`, except that functions marked with `reinitializer` | |
* cannot be nested. If one is invoked in the context of another, execution will revert. | |
* | |
* Note that versions can jump in increments greater than 1; this implies that if multiple reinitializers coexist in | |
* a contract, executing them in the right order is up to the developer or operator. | |
* | |
* WARNING: setting the version to 255 will prevent any future reinitialization. | |
* | |
* Emits an {Initialized} event. | |
*/ | |
modifier reinitializer(uint8 version) { | |
require(!_initializing && _initialized < version, "Initializable: contract is already initialized"); | |
_initialized = version; | |
_initializing = true; | |
_; | |
_initializing = false; | |
emit Initialized(version); | |
} | |
/** | |
* @dev Modifier to protect an initialization function so that it can only be invoked by functions with the | |
* {initializer} and {reinitializer} modifiers, directly or indirectly. | |
*/ | |
modifier onlyInitializing() { | |
require(_initializing, "Initializable: contract is not initializing"); | |
_; | |
} | |
/** | |
* @dev Locks the contract, preventing any future reinitialization. This cannot be part of an initializer call. | |
* Calling this in the constructor of a contract will prevent that contract from being initialized or reinitialized | |
* to any version. It is recommended to use this to lock implementation contracts that are designed to be called | |
* through proxies. | |
* | |
* Emits an {Initialized} event the first time it is successfully executed. | |
*/ | |
function _disableInitializers() internal virtual { | |
require(!_initializing, "Initializable: contract is initializing"); | |
if (_initialized != type(uint8).max) { | |
_initialized = type(uint8).max; | |
emit Initialized(type(uint8).max); | |
} | |
} | |
/** | |
* @dev Returns the highest version that has been initialized. See {reinitializer}. | |
*/ | |
function _getInitializedVersion() internal view returns (uint8) { | |
return _initialized; | |
} | |
/** | |
* @dev Returns `true` if the contract is currently initializing. See {onlyInitializing}. | |
*/ | |
function _isInitializing() internal view returns (bool) { | |
return _initializing; | |
} | |
} |
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// SPDX-License-Identifier: MIT | |
// OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/ERC20.sol) | |
pragma solidity ^0.8.0; | |
import "./IERC20.sol"; | |
import "./extensions/IERC20Metadata.sol"; | |
import "../../utils/Context.sol"; | |
/** | |
* @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 {ERC20PresetMinterPauser}. | |
* | |
* TIP: For a detailed writeup see our guide | |
* https://forum.openzeppelin.com/t/how-to-implement-erc20-supply-mechanisms/226[How | |
* to implement supply mechanisms]. | |
* | |
* The default value of {decimals} is 18. To change this, you should override | |
* this function so it returns a different value. | |
* | |
* We have followed general OpenZeppelin Contracts guidelines: functions revert | |
* instead 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, IERC20Metadata { | |
mapping(address => uint256) private _balances; | |
mapping(address => mapping(address => uint256)) private _allowances; | |
uint256 private _totalSupply; | |
string private _name; | |
string private _symbol; | |
/** | |
* @dev Sets the values for {name} and {symbol}. | |
* | |
* All two of these values are immutable: they can only be set once during | |
* construction. | |
*/ | |
constructor(string memory name_, string memory symbol_) { | |
_name = name_; | |
_symbol = symbol_; | |
} | |
/** | |
* @dev Returns the name of the token. | |
*/ | |
function name() public view virtual override returns (string memory) { | |
return _name; | |
} | |
/** | |
* @dev Returns the symbol of the token, usually a shorter version of the | |
* name. | |
*/ | |
function symbol() public view virtual override 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. This is the default value returned by this function, unless | |
* it's overridden. | |
* | |
* 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 virtual override returns (uint8) { | |
return 18; | |
} | |
/** | |
* @dev See {IERC20-totalSupply}. | |
*/ | |
function totalSupply() public view virtual override returns (uint256) { | |
return _totalSupply; | |
} | |
/** | |
* @dev See {IERC20-balanceOf}. | |
*/ | |
function balanceOf(address account) public view virtual override returns (uint256) { | |
return _balances[account]; | |
} | |
/** | |
* @dev See {IERC20-transfer}. | |
* | |
* Requirements: | |
* | |
* - `to` cannot be the zero address. | |
* - the caller must have a balance of at least `amount`. | |
*/ | |
function transfer(address to, uint256 amount) public virtual override returns (bool) { | |
address owner = _msgSender(); | |
_transfer(owner, to, amount); | |
return true; | |
} | |
/** | |
* @dev See {IERC20-allowance}. | |
*/ | |
function allowance(address owner, address spender) public view virtual override returns (uint256) { | |
return _allowances[owner][spender]; | |
} | |
/** | |
* @dev See {IERC20-approve}. | |
* | |
* NOTE: If `amount` is the maximum `uint256`, the allowance is not updated on | |
* `transferFrom`. This is semantically equivalent to an infinite approval. | |
* | |
* Requirements: | |
* | |
* - `spender` cannot be the zero address. | |
*/ | |
function approve(address spender, uint256 amount) public virtual override returns (bool) { | |
address owner = _msgSender(); | |
_approve(owner, 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}. | |
* | |
* NOTE: Does not update the allowance if the current allowance | |
* is the maximum `uint256`. | |
* | |
* Requirements: | |
* | |
* - `from` and `to` cannot be the zero address. | |
* - `from` must have a balance of at least `amount`. | |
* - the caller must have allowance for ``from``'s tokens of at least | |
* `amount`. | |
*/ | |
function transferFrom(address from, address to, uint256 amount) public virtual override returns (bool) { | |
address spender = _msgSender(); | |
_spendAllowance(from, spender, amount); | |
_transfer(from, to, amount); | |
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 virtual returns (bool) { | |
address owner = _msgSender(); | |
_approve(owner, spender, allowance(owner, spender) + 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 virtual returns (bool) { | |
address owner = _msgSender(); | |
uint256 currentAllowance = allowance(owner, spender); | |
require(currentAllowance >= subtractedValue, "ERC20: decreased allowance below zero"); | |
unchecked { | |
_approve(owner, spender, currentAllowance - subtractedValue); | |
} | |
return true; | |
} | |
/** | |
* @dev Moves `amount` of tokens from `from` to `to`. | |
* | |
* This 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: | |
* | |
* - `from` cannot be the zero address. | |
* - `to` cannot be the zero address. | |
* - `from` must have a balance of at least `amount`. | |
*/ | |
function _transfer(address from, address to, uint256 amount) internal virtual { | |
require(from != address(0), "ERC20: transfer from the zero address"); | |
require(to != address(0), "ERC20: transfer to the zero address"); | |
_beforeTokenTransfer(from, to, amount); | |
uint256 fromBalance = _balances[from]; | |
require(fromBalance >= amount, "ERC20: transfer amount exceeds balance"); | |
unchecked { | |
_balances[from] = fromBalance - amount; | |
// Overflow not possible: the sum of all balances is capped by totalSupply, and the sum is preserved by | |
// decrementing then incrementing. | |
_balances[to] += amount; | |
} | |
emit Transfer(from, to, amount); | |
_afterTokenTransfer(from, to, 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: | |
* | |
* - `account` cannot be the zero address. | |
*/ | |
function _mint(address account, uint256 amount) internal virtual { | |
require(account != address(0), "ERC20: mint to the zero address"); | |
_beforeTokenTransfer(address(0), account, amount); | |
_totalSupply += amount; | |
unchecked { | |
// Overflow not possible: balance + amount is at most totalSupply + amount, which is checked above. | |
_balances[account] += amount; | |
} | |
emit Transfer(address(0), account, amount); | |
_afterTokenTransfer(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 virtual { | |
require(account != address(0), "ERC20: burn from the zero address"); | |
_beforeTokenTransfer(account, address(0), amount); | |
uint256 accountBalance = _balances[account]; | |
require(accountBalance >= amount, "ERC20: burn amount exceeds balance"); | |
unchecked { | |
_balances[account] = accountBalance - amount; | |
// Overflow not possible: amount <= accountBalance <= totalSupply. | |
_totalSupply -= amount; | |
} | |
emit Transfer(account, address(0), amount); | |
_afterTokenTransfer(account, address(0), amount); | |
} | |
/** | |
* @dev Sets `amount` as the allowance of `spender` over the `owner` s tokens. | |
* | |
* This 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 virtual { | |
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 Updates `owner` s allowance for `spender` based on spent `amount`. | |
* | |
* Does not update the allowance amount in case of infinite allowance. | |
* Revert if not enough allowance is available. | |
* | |
* Might emit an {Approval} event. | |
*/ | |
function _spendAllowance(address owner, address spender, uint256 amount) internal virtual { | |
uint256 currentAllowance = allowance(owner, spender); | |
if (currentAllowance != type(uint256).max) { | |
require(currentAllowance >= amount, "ERC20: insufficient allowance"); | |
unchecked { | |
_approve(owner, spender, currentAllowance - amount); | |
} | |
} | |
} | |
/** | |
* @dev Hook that is called before any transfer of tokens. This includes | |
* minting and burning. | |
* | |
* Calling conditions: | |
* | |
* - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens | |
* will be transferred to `to`. | |
* - when `from` is zero, `amount` tokens will be minted for `to`. | |
* - when `to` is zero, `amount` of ``from``'s tokens will be burned. | |
* - `from` and `to` are never both zero. | |
* | |
* To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks]. | |
*/ | |
function _beforeTokenTransfer(address from, address to, uint256 amount) internal virtual {} | |
/** | |
* @dev Hook that is called after any transfer of tokens. This includes | |
* minting and burning. | |
* | |
* Calling conditions: | |
* | |
* - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens | |
* has been transferred to `to`. | |
* - when `from` is zero, `amount` tokens have been minted for `to`. | |
* - when `to` is zero, `amount` of ``from``'s tokens have been burned. | |
* - `from` and `to` are never both zero. | |
* | |
* To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks]. | |
*/ | |
function _afterTokenTransfer(address from, address to, uint256 amount) internal virtual {} | |
} |
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// SPDX-License-Identifier: MIT | |
// OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/IERC20Metadata.sol) | |
pragma solidity ^0.8.0; | |
import "../IERC20.sol"; | |
/** | |
* @dev Interface for the optional metadata functions from the ERC20 standard. | |
* | |
* _Available since v4.1._ | |
*/ | |
interface IERC20Metadata is IERC20 { | |
/** | |
* @dev Returns the name of the token. | |
*/ | |
function name() external view returns (string memory); | |
/** | |
* @dev Returns the symbol of the token. | |
*/ | |
function symbol() external view returns (string memory); | |
/** | |
* @dev Returns the decimals places of the token. | |
*/ | |
function decimals() external view returns (uint8); | |
} |
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// SPDX-License-Identifier: MIT | |
// OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/IERC20.sol) | |
pragma solidity ^0.8.0; | |
/** | |
* @dev Interface of the ERC20 standard as defined in the EIP. | |
*/ | |
interface IERC20 { | |
/** | |
* @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 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 `to`. | |
* | |
* Returns a boolean value indicating whether the operation succeeded. | |
* | |
* Emits a {Transfer} event. | |
*/ | |
function transfer(address to, 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 `from` to `to` 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 from, address to, uint256 amount) external returns (bool); | |
} |
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// SPDX-License-Identifier: MIT | |
// OpenZeppelin Contracts (last updated v4.9.0) (utils/Address.sol) | |
pragma solidity ^0.8.1; | |
/** | |
* @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 | |
* | |
* Furthermore, `isContract` will also return true if the target contract within | |
* the same transaction is already scheduled for destruction by `SELFDESTRUCT`, | |
* which only has an effect at the end of a transaction. | |
* ==== | |
* | |
* [IMPORTANT] | |
* ==== | |
* You shouldn't rely on `isContract` to protect against flash loan attacks! | |
* | |
* Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets | |
* like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract | |
* constructor. | |
* ==== | |
*/ | |
function isContract(address account) internal view returns (bool) { | |
// This method relies on extcodesize/address.code.length, which returns 0 | |
// for contracts in construction, since the code is only stored at the end | |
// of the constructor execution. | |
return account.code.length > 0; | |
} | |
/** | |
* @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://consensys.net/diligence/blog/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/v0.8.0/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"); | |
(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 functionCallWithValue(target, data, 0, "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"); | |
(bool success, bytes memory returndata) = target.call{value: value}(data); | |
return verifyCallResultFromTarget(target, success, returndata, errorMessage); | |
} | |
/** | |
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], | |
* but performing a static call. | |
* | |
* _Available since v3.3._ | |
*/ | |
function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) { | |
return functionStaticCall(target, data, "Address: low-level static call failed"); | |
} | |
/** | |
* @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`], | |
* but performing a static call. | |
* | |
* _Available since v3.3._ | |
*/ | |
function functionStaticCall( | |
address target, | |
bytes memory data, | |
string memory errorMessage | |
) internal view returns (bytes memory) { | |
(bool success, bytes memory returndata) = target.staticcall(data); | |
return verifyCallResultFromTarget(target, success, returndata, errorMessage); | |
} | |
/** | |
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], | |
* but performing a delegate call. | |
* | |
* _Available since v3.4._ | |
*/ | |
function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) { | |
return functionDelegateCall(target, data, "Address: low-level delegate call failed"); | |
} | |
/** | |
* @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`], | |
* but performing a delegate call. | |
* | |
* _Available since v3.4._ | |
*/ | |
function functionDelegateCall( | |
address target, | |
bytes memory data, | |
string memory errorMessage | |
) internal returns (bytes memory) { | |
(bool success, bytes memory returndata) = target.delegatecall(data); | |
return verifyCallResultFromTarget(target, success, returndata, errorMessage); | |
} | |
/** | |
* @dev Tool to verify that a low level call to smart-contract was successful, and revert (either by bubbling | |
* the revert reason or using the provided one) in case of unsuccessful call or if target was not a contract. | |
* | |
* _Available since v4.8._ | |
*/ | |
function verifyCallResultFromTarget( | |
address target, | |
bool success, | |
bytes memory returndata, | |
string memory errorMessage | |
) internal view returns (bytes memory) { | |
if (success) { | |
if (returndata.length == 0) { | |
// only check isContract if the call was successful and the return data is empty | |
// otherwise we already know that it was a contract | |
require(isContract(target), "Address: call to non-contract"); | |
} | |
return returndata; | |
} else { | |
_revert(returndata, errorMessage); | |
} | |
} | |
/** | |
* @dev Tool to verify that a low level call was successful, and revert if it wasn't, either by bubbling the | |
* revert reason or using the provided one. | |
* | |
* _Available since v4.3._ | |
*/ | |
function verifyCallResult( | |
bool success, | |
bytes memory returndata, | |
string memory errorMessage | |
) internal pure returns (bytes memory) { | |
if (success) { | |
return returndata; | |
} else { | |
_revert(returndata, errorMessage); | |
} | |
} | |
function _revert(bytes memory returndata, string memory errorMessage) private pure { | |
// 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 | |
/// @solidity memory-safe-assembly | |
assembly { | |
let returndata_size := mload(returndata) | |
revert(add(32, returndata), returndata_size) | |
} | |
} else { | |
revert(errorMessage); | |
} | |
} | |
} |
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// SPDX-License-Identifier: MIT | |
// OpenZeppelin Contracts v4.4.1 (utils/Context.sol) | |
pragma solidity ^0.8.0; | |
/** | |
* @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 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. | |
*/ | |
abstract contract Context { | |
function _msgSender() internal view virtual returns (address) { | |
return msg.sender; | |
} | |
function _msgData() internal view virtual returns (bytes calldata) { | |
return msg.data; | |
} | |
} |
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// SPDX-License-Identifier: MIT | |
// OpenZeppelin Contracts v4.4.1 (utils/introspection/ERC165.sol) | |
pragma solidity ^0.8.0; | |
import "./IERC165.sol"; | |
/** | |
* @dev Implementation of the {IERC165} interface. | |
* | |
* Contracts that want to implement ERC165 should inherit from this contract and override {supportsInterface} to check | |
* for the additional interface id that will be supported. For example: | |
* | |
* ```solidity | |
* function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) { | |
* return interfaceId == type(MyInterface).interfaceId || super.supportsInterface(interfaceId); | |
* } | |
* ``` | |
* | |
* Alternatively, {ERC165Storage} provides an easier to use but more expensive implementation. | |
*/ | |
abstract contract ERC165 is IERC165 { | |
/** | |
* @dev See {IERC165-supportsInterface}. | |
*/ | |
function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) { | |
return interfaceId == type(IERC165).interfaceId; | |
} | |
} |
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// SPDX-License-Identifier: MIT | |
// OpenZeppelin Contracts v4.4.1 (utils/introspection/IERC165.sol) | |
pragma solidity ^0.8.0; | |
/** | |
* @dev Interface of the ERC165 standard, as defined in the | |
* https://eips.ethereum.org/EIPS/eip-165[EIP]. | |
* | |
* Implementers can declare support of contract interfaces, which can then be | |
* queried by others ({ERC165Checker}). | |
* | |
* For an implementation, see {ERC165}. | |
*/ | |
interface IERC165 { | |
/** | |
* @dev Returns true if this contract implements the interface defined by | |
* `interfaceId`. See the corresponding | |
* https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section] | |
* to learn more about how these ids are created. | |
* | |
* This function call must use less than 30 000 gas. | |
*/ | |
function supportsInterface(bytes4 interfaceId) external view returns (bool); | |
} |
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// SPDX-License-Identifier: MIT | |
// OpenZeppelin Contracts (last updated v5.0.0) (access/Ownable.sol) | |
pragma solidity ^0.8.20; | |
import {Context} from "../utils/Context.sol"; | |
/** | |
* @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. | |
* | |
* The initial owner is set to the address provided by the deployer. 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. | |
*/ | |
abstract contract Ownable is Context { | |
address private _owner; | |
/** | |
* @dev The caller account is not authorized to perform an operation. | |
*/ | |
error OwnableUnauthorizedAccount(address account); | |
/** | |
* @dev The owner is not a valid owner account. (eg. `address(0)`) | |
*/ | |
error OwnableInvalidOwner(address owner); | |
event OwnershipTransferred(address indexed previousOwner, address indexed newOwner); | |
/** | |
* @dev Initializes the contract setting the address provided by the deployer as the initial owner. | |
*/ | |
constructor(address initialOwner) { | |
if (initialOwner == address(0)) { | |
revert OwnableInvalidOwner(address(0)); | |
} | |
_transferOwnership(initialOwner); | |
} | |
/** | |
* @dev Throws if called by any account other than the owner. | |
*/ | |
modifier onlyOwner() { | |
_checkOwner(); | |
_; | |
} | |
/** | |
* @dev Returns the address of the current owner. | |
*/ | |
function owner() public view virtual returns (address) { | |
return _owner; | |
} | |
/** | |
* @dev Throws if the sender is not the owner. | |
*/ | |
function _checkOwner() internal view virtual { | |
if (owner() != _msgSender()) { | |
revert OwnableUnauthorizedAccount(_msgSender()); | |
} | |
} | |
/** | |
* @dev Leaves the contract without owner. It will not be possible to call | |
* `onlyOwner` functions. Can only be called by the current owner. | |
* | |
* NOTE: Renouncing ownership will leave the contract without an owner, | |
* thereby disabling any functionality that is only available to the owner. | |
*/ | |
function renounceOwnership() public virtual onlyOwner { | |
_transferOwnership(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 virtual onlyOwner { | |
if (newOwner == address(0)) { | |
revert OwnableInvalidOwner(address(0)); | |
} | |
_transferOwnership(newOwner); | |
} | |
/** | |
* @dev Transfers ownership of the contract to a new account (`newOwner`). | |
* Internal function without access restriction. | |
*/ | |
function _transferOwnership(address newOwner) internal virtual { | |
address oldOwner = _owner; | |
_owner = newOwner; | |
emit OwnershipTransferred(oldOwner, newOwner); | |
} | |
} |
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// SPDX-License-Identifier: MIT | |
// OpenZeppelin Contracts (last updated v5.0.0) (proxy/utils/Initializable.sol) | |
pragma solidity ^0.8.20; | |
/** | |
* @dev This is a base contract to aid in writing upgradeable contracts, or any kind of contract that will be deployed | |
* behind a proxy. Since proxied contracts do not make use of a constructor, it's common to move constructor logic to an | |
* external initializer function, usually called `initialize`. It then becomes necessary to protect this initializer | |
* function so it can only be called once. The {initializer} modifier provided by this contract will have this effect. | |
* | |
* The initialization functions use a version number. Once a version number is used, it is consumed and cannot be | |
* reused. This mechanism prevents re-execution of each "step" but allows the creation of new initialization steps in | |
* case an upgrade adds a module that needs to be initialized. | |
* | |
* For example: | |
* | |
* [.hljs-theme-light.nopadding] | |
* ```solidity | |
* contract MyToken is ERC20Upgradeable { | |
* function initialize() initializer public { | |
* __ERC20_init("MyToken", "MTK"); | |
* } | |
* } | |
* | |
* contract MyTokenV2 is MyToken, ERC20PermitUpgradeable { | |
* function initializeV2() reinitializer(2) public { | |
* __ERC20Permit_init("MyToken"); | |
* } | |
* } | |
* ``` | |
* | |
* TIP: To avoid leaving the proxy in an uninitialized state, the initializer function should be called as early as | |
* possible by providing the encoded function call as the `_data` argument to {ERC1967Proxy-constructor}. | |
* | |
* CAUTION: When used with inheritance, manual care must be taken to not invoke a parent initializer twice, or to ensure | |
* that all initializers are idempotent. This is not verified automatically as constructors are by Solidity. | |
* | |
* [CAUTION] | |
* ==== | |
* Avoid leaving a contract uninitialized. | |
* | |
* An uninitialized contract can be taken over by an attacker. This applies to both a proxy and its implementation | |
* contract, which may impact the proxy. To prevent the implementation contract from being used, you should invoke | |
* the {_disableInitializers} function in the constructor to automatically lock it when it is deployed: | |
* | |
* [.hljs-theme-light.nopadding] | |
* ``` | |
* /// @custom:oz-upgrades-unsafe-allow constructor | |
* constructor() { | |
* _disableInitializers(); | |
* } | |
* ``` | |
* ==== | |
*/ | |
abstract contract Initializable { | |
/** | |
* @dev Storage of the initializable contract. | |
* | |
* It's implemented on a custom ERC-7201 namespace to reduce the risk of storage collisions | |
* when using with upgradeable contracts. | |
* | |
* @custom:storage-location erc7201:openzeppelin.storage.Initializable | |
*/ | |
struct InitializableStorage { | |
/** | |
* @dev Indicates that the contract has been initialized. | |
*/ | |
uint64 _initialized; | |
/** | |
* @dev Indicates that the contract is in the process of being initialized. | |
*/ | |
bool _initializing; | |
} | |
// keccak256(abi.encode(uint256(keccak256("openzeppelin.storage.Initializable")) - 1)) & ~bytes32(uint256(0xff)) | |
bytes32 private constant INITIALIZABLE_STORAGE = 0xf0c57e16840df040f15088dc2f81fe391c3923bec73e23a9662efc9c229c6a00; | |
/** | |
* @dev The contract is already initialized. | |
*/ | |
error InvalidInitialization(); | |
/** | |
* @dev The contract is not initializing. | |
*/ | |
error NotInitializing(); | |
/** | |
* @dev Triggered when the contract has been initialized or reinitialized. | |
*/ | |
event Initialized(uint64 version); | |
/** | |
* @dev A modifier that defines a protected initializer function that can be invoked at most once. In its scope, | |
* `onlyInitializing` functions can be used to initialize parent contracts. | |
* | |
* Similar to `reinitializer(1)`, except that in the context of a constructor an `initializer` may be invoked any | |
* number of times. This behavior in the constructor can be useful during testing and is not expected to be used in | |
* production. | |
* | |
* Emits an {Initialized} event. | |
*/ | |
modifier initializer() { | |
// solhint-disable-next-line var-name-mixedcase | |
InitializableStorage storage $ = _getInitializableStorage(); | |
// Cache values to avoid duplicated sloads | |
bool isTopLevelCall = !$._initializing; | |
uint64 initialized = $._initialized; | |
// Allowed calls: | |
// - initialSetup: the contract is not in the initializing state and no previous version was | |
// initialized | |
// - construction: the contract is initialized at version 1 (no reininitialization) and the | |
// current contract is just being deployed | |
bool initialSetup = initialized == 0 && isTopLevelCall; | |
bool construction = initialized == 1 && address(this).code.length == 0; | |
if (!initialSetup && !construction) { | |
revert InvalidInitialization(); | |
} | |
$._initialized = 1; | |
if (isTopLevelCall) { | |
$._initializing = true; | |
} | |
_; | |
if (isTopLevelCall) { | |
$._initializing = false; | |
emit Initialized(1); | |
} | |
} | |
/** | |
* @dev A modifier that defines a protected reinitializer function that can be invoked at most once, and only if the | |
* contract hasn't been initialized to a greater version before. In its scope, `onlyInitializing` functions can be | |
* used to initialize parent contracts. | |
* | |
* A reinitializer may be used after the original initialization step. This is essential to configure modules that | |
* are added through upgrades and that require initialization. | |
* | |
* When `version` is 1, this modifier is similar to `initializer`, except that functions marked with `reinitializer` | |
* cannot be nested. If one is invoked in the context of another, execution will revert. | |
* | |
* Note that versions can jump in increments greater than 1; this implies that if multiple reinitializers coexist in | |
* a contract, executing them in the right order is up to the developer or operator. | |
* | |
* WARNING: Setting the version to 2**64 - 1 will prevent any future reinitialization. | |
* | |
* Emits an {Initialized} event. | |
*/ | |
modifier reinitializer(uint64 version) { | |
// solhint-disable-next-line var-name-mixedcase | |
InitializableStorage storage $ = _getInitializableStorage(); | |
if ($._initializing || $._initialized >= version) { | |
revert InvalidInitialization(); | |
} | |
$._initialized = version; | |
$._initializing = true; | |
_; | |
$._initializing = false; | |
emit Initialized(version); | |
} | |
/** | |
* @dev Modifier to protect an initialization function so that it can only be invoked by functions with the | |
* {initializer} and {reinitializer} modifiers, directly or indirectly. | |
*/ | |
modifier onlyInitializing() { | |
_checkInitializing(); | |
_; | |
} | |
/** | |
* @dev Reverts if the contract is not in an initializing state. See {onlyInitializing}. | |
*/ | |
function _checkInitializing() internal view virtual { | |
if (!_isInitializing()) { | |
revert NotInitializing(); | |
} | |
} | |
/** | |
* @dev Locks the contract, preventing any future reinitialization. This cannot be part of an initializer call. | |
* Calling this in the constructor of a contract will prevent that contract from being initialized or reinitialized | |
* to any version. It is recommended to use this to lock implementation contracts that are designed to be called | |
* through proxies. | |
* | |
* Emits an {Initialized} event the first time it is successfully executed. | |
*/ | |
function _disableInitializers() internal virtual { | |
// solhint-disable-next-line var-name-mixedcase | |
InitializableStorage storage $ = _getInitializableStorage(); | |
if ($._initializing) { | |
revert InvalidInitialization(); | |
} | |
if ($._initialized != type(uint64).max) { | |
$._initialized = type(uint64).max; | |
emit Initialized(type(uint64).max); | |
} | |
} | |
/** | |
* @dev Returns the highest version that has been initialized. See {reinitializer}. | |
*/ | |
function _getInitializedVersion() internal view returns (uint64) { | |
return _getInitializableStorage()._initialized; | |
} | |
/** | |
* @dev Returns `true` if the contract is currently initializing. See {onlyInitializing}. | |
*/ | |
function _isInitializing() internal view returns (bool) { | |
return _getInitializableStorage()._initializing; | |
} | |
/** | |
* @dev Returns a pointer to the storage namespace. | |
*/ | |
// solhint-disable-next-line var-name-mixedcase | |
function _getInitializableStorage() private pure returns (InitializableStorage storage $) { | |
assembly { | |
$.slot := INITIALIZABLE_STORAGE | |
} | |
} | |
} |
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// SPDX-License-Identifier: MIT | |
// OpenZeppelin Contracts (last updated v4.7.0) (security/Pausable.sol) | |
pragma solidity ^0.8.0; | |
import "../utils/Context.sol"; | |
/** | |
* @dev Contract module which allows children to implement an emergency stop | |
* mechanism that can be triggered by an authorized account. | |
* | |
* This module is used through inheritance. It will make available the | |
* modifiers `whenNotPaused` and `whenPaused`, which can be applied to | |
* the functions of your contract. Note that they will not be pausable by | |
* simply including this module, only once the modifiers are put in place. | |
*/ | |
abstract contract Pausable is Context { | |
/** | |
* @dev Emitted when the pause is triggered by `account`. | |
*/ | |
event Paused(address account); | |
/** | |
* @dev Emitted when the pause is lifted by `account`. | |
*/ | |
event Unpaused(address account); | |
bool private _paused; | |
/** | |
* @dev Initializes the contract in unpaused state. | |
*/ | |
constructor() { | |
_paused = false; | |
} | |
/** | |
* @dev Modifier to make a function callable only when the contract is not paused. | |
* | |
* Requirements: | |
* | |
* - The contract must not be paused. | |
*/ | |
modifier whenNotPaused() { | |
_requireNotPaused(); | |
_; | |
} | |
/** | |
* @dev Modifier to make a function callable only when the contract is paused. | |
* | |
* Requirements: | |
* | |
* - The contract must be paused. | |
*/ | |
modifier whenPaused() { | |
_requirePaused(); | |
_; | |
} | |
/** | |
* @dev Returns true if the contract is paused, and false otherwise. | |
*/ | |
function paused() public view virtual returns (bool) { | |
return _paused; | |
} | |
/** | |
* @dev Throws if the contract is paused. | |
*/ | |
function _requireNotPaused() internal view virtual { | |
require(!paused(), "Pausable: paused"); | |
} | |
/** | |
* @dev Throws if the contract is not paused. | |
*/ | |
function _requirePaused() internal view virtual { | |
require(paused(), "Pausable: not paused"); | |
} | |
/** | |
* @dev Triggers stopped state. | |
* | |
* Requirements: | |
* | |
* - The contract must not be paused. | |
*/ | |
function _pause() internal virtual whenNotPaused { | |
_paused = true; | |
emit Paused(_msgSender()); | |
} | |
/** | |
* @dev Returns to normal state. | |
* | |
* Requirements: | |
* | |
* - The contract must be paused. | |
*/ | |
function _unpause() internal virtual whenPaused { | |
_paused = false; | |
emit Unpaused(_msgSender()); | |
} | |
} |
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// SPDX-License-Identifier: MIT | |
// OpenZeppelin Contracts (last updated v4.9.0) (security/ReentrancyGuard.sol) | |
pragma solidity ^0.8.0; | |
/** | |
* @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]. | |
*/ | |
abstract contract ReentrancyGuard { | |
// Booleans are more expensive than uint256 or any type that takes up a full | |
// word because each write operation emits an extra SLOAD to first read the | |
// slot's contents, replace the bits taken up by the boolean, and then write | |
// back. This is the compiler's defense against contract upgrades and | |
// pointer aliasing, and it cannot be disabled. | |
// The values being 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 percentage 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. | |
uint256 private constant _NOT_ENTERED = 1; | |
uint256 private constant _ENTERED = 2; | |
uint256 private _status; | |
constructor() { | |
_status = _NOT_ENTERED; | |
} | |
/** | |
* @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 making it call a | |
* `private` function that does the actual work. | |
*/ | |
modifier nonReentrant() { | |
_nonReentrantBefore(); | |
_; | |
_nonReentrantAfter(); | |
} | |
function _nonReentrantBefore() private { | |
// On the first call to nonReentrant, _status will be _NOT_ENTERED | |
require(_status != _ENTERED, "ReentrancyGuard: reentrant call"); | |
// Any calls to nonReentrant after this point will fail | |
_status = _ENTERED; | |
} | |
function _nonReentrantAfter() private { | |
// By storing the original value once again, a refund is triggered (see | |
// https://eips.ethereum.org/EIPS/eip-2200) | |
_status = _NOT_ENTERED; | |
} | |
/** | |
* @dev Returns true if the reentrancy guard is currently set to "entered", which indicates there is a | |
* `nonReentrant` function in the call stack. | |
*/ | |
function _reentrancyGuardEntered() internal view returns (bool) { | |
return _status == _ENTERED; | |
} | |
} |
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// SPDX-License-Identifier: MIT | |
// OpenZeppelin Contracts (last updated v5.0.0) (token/ERC20/ERC20.sol) | |
pragma solidity ^0.8.20; | |
import {IERC20} from "./IERC20.sol"; | |
import {IERC20Metadata} from "./extensions/IERC20Metadata.sol"; | |
import {Context} from "../../utils/Context.sol"; | |
import {IERC20Errors} from "../../interfaces/draft-IERC6093.sol"; | |
/** | |
* @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}. | |
* | |
* TIP: For a detailed writeup see our guide | |
* https://forum.openzeppelin.com/t/how-to-implement-erc20-supply-mechanisms/226[How | |
* to implement supply mechanisms]. | |
* | |
* The default value of {decimals} is 18. To change this, you should override | |
* this function so it returns a different value. | |
* | |
* We have followed general OpenZeppelin Contracts guidelines: functions revert | |
* instead 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. | |
*/ | |
abstract contract ERC20 is Context, IERC20, IERC20Metadata, IERC20Errors { | |
mapping(address account => uint256) private _balances; | |
mapping(address account => mapping(address spender => uint256)) private _allowances; | |
uint256 private _totalSupply; | |
string private _name; | |
string private _symbol; | |
/** | |
* @dev Sets the values for {name} and {symbol}. | |
* | |
* All two of these values are immutable: they can only be set once during | |
* construction. | |
*/ | |
constructor(string memory name_, string memory symbol_) { | |
_name = name_; | |
_symbol = symbol_; | |
} | |
/** | |
* @dev Returns the name of the token. | |
*/ | |
function name() public view virtual returns (string memory) { | |
return _name; | |
} | |
/** | |
* @dev Returns the symbol of the token, usually a shorter version of the | |
* name. | |
*/ | |
function symbol() public view virtual 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. This is the default value returned by this function, unless | |
* it's overridden. | |
* | |
* 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 virtual returns (uint8) { | |
return 18; | |
} | |
/** | |
* @dev See {IERC20-totalSupply}. | |
*/ | |
function totalSupply() public view virtual returns (uint256) { | |
return _totalSupply; | |
} | |
/** | |
* @dev See {IERC20-balanceOf}. | |
*/ | |
function balanceOf(address account) public view virtual returns (uint256) { | |
return _balances[account]; | |
} | |
/** | |
* @dev See {IERC20-transfer}. | |
* | |
* Requirements: | |
* | |
* - `to` cannot be the zero address. | |
* - the caller must have a balance of at least `value`. | |
*/ | |
function transfer(address to, uint256 value) public virtual returns (bool) { | |
address owner = _msgSender(); | |
_transfer(owner, to, value); | |
return true; | |
} | |
/** | |
* @dev See {IERC20-allowance}. | |
*/ | |
function allowance(address owner, address spender) public view virtual returns (uint256) { | |
return _allowances[owner][spender]; | |
} | |
/** | |
* @dev See {IERC20-approve}. | |
* | |
* NOTE: If `value` is the maximum `uint256`, the allowance is not updated on | |
* `transferFrom`. This is semantically equivalent to an infinite approval. | |
* | |
* Requirements: | |
* | |
* - `spender` cannot be the zero address. | |
*/ | |
function approve(address spender, uint256 value) public virtual returns (bool) { | |
address owner = _msgSender(); | |
_approve(owner, spender, value); | |
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}. | |
* | |
* NOTE: Does not update the allowance if the current allowance | |
* is the maximum `uint256`. | |
* | |
* Requirements: | |
* | |
* - `from` and `to` cannot be the zero address. | |
* - `from` must have a balance of at least `value`. | |
* - the caller must have allowance for ``from``'s tokens of at least | |
* `value`. | |
*/ | |
function transferFrom(address from, address to, uint256 value) public virtual returns (bool) { | |
address spender = _msgSender(); | |
_spendAllowance(from, spender, value); | |
_transfer(from, to, value); | |
return true; | |
} | |
/** | |
* @dev Moves a `value` amount of tokens from `from` to `to`. | |
* | |
* This internal function is equivalent to {transfer}, and can be used to | |
* e.g. implement automatic token fees, slashing mechanisms, etc. | |
* | |
* Emits a {Transfer} event. | |
* | |
* NOTE: This function is not virtual, {_update} should be overridden instead. | |
*/ | |
function _transfer(address from, address to, uint256 value) internal { | |
if (from == address(0)) { | |
revert ERC20InvalidSender(address(0)); | |
} | |
if (to == address(0)) { | |
revert ERC20InvalidReceiver(address(0)); | |
} | |
_update(from, to, value); | |
} | |
/** | |
* @dev Transfers a `value` amount of tokens from `from` to `to`, or alternatively mints (or burns) if `from` | |
* (or `to`) is the zero address. All customizations to transfers, mints, and burns should be done by overriding | |
* this function. | |
* | |
* Emits a {Transfer} event. | |
*/ | |
function _update(address from, address to, uint256 value) internal virtual { | |
if (from == address(0)) { | |
// Overflow check required: The rest of the code assumes that totalSupply never overflows | |
_totalSupply += value; | |
} else { | |
uint256 fromBalance = _balances[from]; | |
if (fromBalance < value) { | |
revert ERC20InsufficientBalance(from, fromBalance, value); | |
} | |
unchecked { | |
// Overflow not possible: value <= fromBalance <= totalSupply. | |
_balances[from] = fromBalance - value; | |
} | |
} | |
if (to == address(0)) { | |
unchecked { | |
// Overflow not possible: value <= totalSupply or value <= fromBalance <= totalSupply. | |
_totalSupply -= value; | |
} | |
} else { | |
unchecked { | |
// Overflow not possible: balance + value is at most totalSupply, which we know fits into a uint256. | |
_balances[to] += value; | |
} | |
} | |
emit Transfer(from, to, value); | |
} | |
/** | |
* @dev Creates a `value` amount of tokens and assigns them to `account`, by transferring it from address(0). | |
* Relies on the `_update` mechanism | |
* | |
* Emits a {Transfer} event with `from` set to the zero address. | |
* | |
* NOTE: This function is not virtual, {_update} should be overridden instead. | |
*/ | |
function _mint(address account, uint256 value) internal { | |
if (account == address(0)) { | |
revert ERC20InvalidReceiver(address(0)); | |
} | |
_update(address(0), account, value); | |
} | |
/** | |
* @dev Destroys a `value` amount of tokens from `account`, lowering the total supply. | |
* Relies on the `_update` mechanism. | |
* | |
* Emits a {Transfer} event with `to` set to the zero address. | |
* | |
* NOTE: This function is not virtual, {_update} should be overridden instead | |
*/ | |
function _burn(address account, uint256 value) internal { | |
if (account == address(0)) { | |
revert ERC20InvalidSender(address(0)); | |
} | |
_update(account, address(0), value); | |
} | |
/** | |
* @dev Sets `value` as the allowance of `spender` over the `owner` s tokens. | |
* | |
* This 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. | |
* | |
* Overrides to this logic should be done to the variant with an additional `bool emitEvent` argument. | |
*/ | |
function _approve(address owner, address spender, uint256 value) internal { | |
_approve(owner, spender, value, true); | |
} | |
/** | |
* @dev Variant of {_approve} with an optional flag to enable or disable the {Approval} event. | |
* | |
* By default (when calling {_approve}) the flag is set to true. On the other hand, approval changes made by | |
* `_spendAllowance` during the `transferFrom` operation set the flag to false. This saves gas by not emitting any | |
* `Approval` event during `transferFrom` operations. | |
* | |
* Anyone who wishes to continue emitting `Approval` events on the`transferFrom` operation can force the flag to | |
* true using the following override: | |
* ``` | |
* function _approve(address owner, address spender, uint256 value, bool) internal virtual override { | |
* super._approve(owner, spender, value, true); | |
* } | |
* ``` | |
* | |
* Requirements are the same as {_approve}. | |
*/ | |
function _approve(address owner, address spender, uint256 value, bool emitEvent) internal virtual { | |
if (owner == address(0)) { | |
revert ERC20InvalidApprover(address(0)); | |
} | |
if (spender == address(0)) { | |
revert ERC20InvalidSpender(address(0)); | |
} | |
_allowances[owner][spender] = value; | |
if (emitEvent) { | |
emit Approval(owner, spender, value); | |
} | |
} | |
/** | |
* @dev Updates `owner` s allowance for `spender` based on spent `value`. | |
* | |
* Does not update the allowance value in case of infinite allowance. | |
* Revert if not enough allowance is available. | |
* | |
* Does not emit an {Approval} event. | |
*/ | |
function _spendAllowance(address owner, address spender, uint256 value) internal virtual { | |
uint256 currentAllowance = allowance(owner, spender); | |
if (currentAllowance != type(uint256).max) { | |
if (currentAllowance < value) { | |
revert ERC20InsufficientAllowance(spender, currentAllowance, value); | |
} | |
unchecked { | |
_approve(owner, spender, currentAllowance - value, false); | |
} | |
} | |
} | |
} |
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// SPDX-License-Identifier: MIT | |
// OpenZeppelin Contracts (last updated v5.0.0) (token/ERC20/IERC20.sol) | |
pragma solidity ^0.8.20; | |
/** | |
* @dev Interface of the ERC20 standard as defined in the EIP. | |
*/ | |
interface IERC20 { | |
/** | |
* @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 Returns the value of tokens in existence. | |
*/ | |
function totalSupply() external view returns (uint256); | |
/** | |
* @dev Returns the value of tokens owned by `account`. | |
*/ | |
function balanceOf(address account) external view returns (uint256); | |
/** | |
* @dev Moves a `value` amount of tokens from the caller's account to `to`. | |
* | |
* Returns a boolean value indicating whether the operation succeeded. | |
* | |
* Emits a {Transfer} event. | |
*/ | |
function transfer(address to, uint256 value) 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 a `value` amount of tokens 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 value) external returns (bool); | |
/** | |
* @dev Moves a `value` amount of tokens from `from` to `to` using the | |
* allowance mechanism. `value` is then deducted from the caller's | |
* allowance. | |
* | |
* Returns a boolean value indicating whether the operation succeeded. | |
* | |
* Emits a {Transfer} event. | |
*/ | |
function transferFrom(address from, address to, uint256 value) external returns (bool); | |
} |
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// SPDX-License-Identifier: MIT | |
// OpenZeppelin Contracts (last updated v5.0.0) (token/ERC20/utils/SafeERC20.sol) | |
pragma solidity ^0.8.20; | |
import {IERC20} from "../IERC20.sol"; | |
import {IERC20Permit} from "../extensions/IERC20Permit.sol"; | |
import {Address} from "../../../utils/Address.sol"; | |
/** | |
* @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 IERC20;` statement to your contract, | |
* which allows you to call the safe operations as `token.safeTransfer(...)`, etc. | |
*/ | |
library SafeERC20 { | |
using Address for address; | |
/** | |
* @dev An operation with an ERC20 token failed. | |
*/ | |
error SafeERC20FailedOperation(address token); | |
/** | |
* @dev Indicates a failed `decreaseAllowance` request. | |
*/ | |
error SafeERC20FailedDecreaseAllowance(address spender, uint256 currentAllowance, uint256 requestedDecrease); | |
/** | |
* @dev Transfer `value` amount of `token` from the calling contract to `to`. If `token` returns no value, | |
* non-reverting calls are assumed to be successful. | |
*/ | |
function safeTransfer(IERC20 token, address to, uint256 value) internal { | |
_callOptionalReturn(token, abi.encodeCall(token.transfer, (to, value))); | |
} | |
/** | |
* @dev Transfer `value` amount of `token` from `from` to `to`, spending the approval given by `from` to the | |
* calling contract. If `token` returns no value, non-reverting calls are assumed to be successful. | |
*/ | |
function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal { | |
_callOptionalReturn(token, abi.encodeCall(token.transferFrom, (from, to, value))); | |
} | |
/** | |
* @dev Increase the calling contract's allowance toward `spender` by `value`. If `token` returns no value, | |
* non-reverting calls are assumed to be successful. | |
*/ | |
function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal { | |
uint256 oldAllowance = token.allowance(address(this), spender); | |
forceApprove(token, spender, oldAllowance + value); | |
} | |
/** | |
* @dev Decrease the calling contract's allowance toward `spender` by `requestedDecrease`. If `token` returns no | |
* value, non-reverting calls are assumed to be successful. | |
*/ | |
function safeDecreaseAllowance(IERC20 token, address spender, uint256 requestedDecrease) internal { | |
unchecked { | |
uint256 currentAllowance = token.allowance(address(this), spender); | |
if (currentAllowance < requestedDecrease) { | |
revert SafeERC20FailedDecreaseAllowance(spender, currentAllowance, requestedDecrease); | |
} | |
forceApprove(token, spender, currentAllowance - requestedDecrease); | |
} | |
} | |
/** | |
* @dev Set the calling contract's allowance toward `spender` to `value`. If `token` returns no value, | |
* non-reverting calls are assumed to be successful. Meant to be used with tokens that require the approval | |
* to be set to zero before setting it to a non-zero value, such as USDT. | |
*/ | |
function forceApprove(IERC20 token, address spender, uint256 value) internal { | |
bytes memory approvalCall = abi.encodeCall(token.approve, (spender, value)); | |
if (!_callOptionalReturnBool(token, approvalCall)) { | |
_callOptionalReturn(token, abi.encodeCall(token.approve, (spender, 0))); | |
_callOptionalReturn(token, approvalCall); | |
} | |
} | |
/** | |
* @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. 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); | |
if (returndata.length != 0 && !abi.decode(returndata, (bool))) { | |
revert SafeERC20FailedOperation(address(token)); | |
} | |
} | |
/** | |
* @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). | |
* | |
* This is a variant of {_callOptionalReturn} that silents catches all reverts and returns a bool instead. | |
*/ | |
function _callOptionalReturnBool(IERC20 token, bytes memory data) private returns (bool) { | |
// 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 cannot use {Address-functionCall} here since this should return false | |
// and not revert is the subcall reverts. | |
(bool success, bytes memory returndata) = address(token).call(data); | |
return success && (returndata.length == 0 || abi.decode(returndata, (bool))) && address(token).code.length > 0; | |
} | |
} |
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// SPDX-License-Identifier: MIT | |
// OpenZeppelin Contracts (last updated v5.0.0) (utils/Address.sol) | |
pragma solidity ^0.8.20; | |
/** | |
* @dev Collection of functions related to the address type | |
*/ | |
library Address { | |
/** | |
* @dev The ETH balance of the account is not enough to perform the operation. | |
*/ | |
error AddressInsufficientBalance(address account); | |
/** | |
* @dev There's no code at `target` (it is not a contract). | |
*/ | |
error AddressEmptyCode(address target); | |
/** | |
* @dev A call to an address target failed. The target may have reverted. | |
*/ | |
error FailedInnerCall(); | |
/** | |
* @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://consensys.net/diligence/blog/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/v0.8.20/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern]. | |
*/ | |
function sendValue(address payable recipient, uint256 amount) internal { | |
if (address(this).balance < amount) { | |
revert AddressInsufficientBalance(address(this)); | |
} | |
(bool success, ) = recipient.call{value: amount}(""); | |
if (!success) { | |
revert FailedInnerCall(); | |
} | |
} | |
/** | |
* @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 or custom error, it is bubbled | |
* up by this function (like regular Solidity function calls). However, if | |
* the call reverted with no returned reason, this function reverts with a | |
* {FailedInnerCall} error. | |
* | |
* 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. | |
*/ | |
function functionCall(address target, bytes memory data) internal returns (bytes memory) { | |
return functionCallWithValue(target, data, 0); | |
} | |
/** | |
* @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`. | |
*/ | |
function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) { | |
if (address(this).balance < value) { | |
revert AddressInsufficientBalance(address(this)); | |
} | |
(bool success, bytes memory returndata) = target.call{value: value}(data); | |
return verifyCallResultFromTarget(target, success, returndata); | |
} | |
/** | |
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], | |
* but performing a static call. | |
*/ | |
function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) { | |
(bool success, bytes memory returndata) = target.staticcall(data); | |
return verifyCallResultFromTarget(target, success, returndata); | |
} | |
/** | |
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], | |
* but performing a delegate call. | |
*/ | |
function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) { | |
(bool success, bytes memory returndata) = target.delegatecall(data); | |
return verifyCallResultFromTarget(target, success, returndata); | |
} | |
/** | |
* @dev Tool to verify that a low level call to smart-contract was successful, and reverts if the target | |
* was not a contract or bubbling up the revert reason (falling back to {FailedInnerCall}) in case of an | |
* unsuccessful call. | |
*/ | |
function verifyCallResultFromTarget( | |
address target, | |
bool success, | |
bytes memory returndata | |
) internal view returns (bytes memory) { | |
if (!success) { | |
_revert(returndata); | |
} else { | |
// only check if target is a contract if the call was successful and the return data is empty | |
// otherwise we already know that it was a contract | |
if (returndata.length == 0 && target.code.length == 0) { | |
revert AddressEmptyCode(target); | |
} | |
return returndata; | |
} | |
} | |
/** | |
* @dev Tool to verify that a low level call was successful, and reverts if it wasn't, either by bubbling the | |
* revert reason or with a default {FailedInnerCall} error. | |
*/ | |
function verifyCallResult(bool success, bytes memory returndata) internal pure returns (bytes memory) { | |
if (!success) { | |
_revert(returndata); | |
} else { | |
return returndata; | |
} | |
} | |
/** | |
* @dev Reverts with returndata if present. Otherwise reverts with {FailedInnerCall}. | |
*/ | |
function _revert(bytes memory returndata) private pure { | |
// 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 | |
/// @solidity memory-safe-assembly | |
assembly { | |
let returndata_size := mload(returndata) | |
revert(add(32, returndata), returndata_size) | |
} | |
} else { | |
revert FailedInnerCall(); | |
} | |
} | |
} |
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// SPDX-License-Identifier: MIT | |
// OpenZeppelin Contracts (last updated v5.0.0) (utils/introspection/ERC165.sol) | |
pragma solidity ^0.8.20; | |
import {IERC165} from "./IERC165.sol"; | |
/** | |
* @dev Implementation of the {IERC165} interface. | |
* | |
* Contracts that want to implement ERC165 should inherit from this contract and override {supportsInterface} to check | |
* for the additional interface id that will be supported. For example: | |
* | |
* ```solidity | |
* function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) { | |
* return interfaceId == type(MyInterface).interfaceId || super.supportsInterface(interfaceId); | |
* } | |
* ``` | |
*/ | |
abstract contract ERC165 is IERC165 { | |
/** | |
* @dev See {IERC165-supportsInterface}. | |
*/ | |
function supportsInterface(bytes4 interfaceId) public view virtual returns (bool) { | |
return interfaceId == type(IERC165).interfaceId; | |
} | |
} |
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// SPDX-License-Identifier: MIT | |
// OpenZeppelin Contracts (last updated v5.0.0) (utils/introspection/IERC165.sol) | |
pragma solidity ^0.8.20; | |
/** | |
* @dev Interface of the ERC165 standard, as defined in the | |
* https://eips.ethereum.org/EIPS/eip-165[EIP]. | |
* | |
* Implementers can declare support of contract interfaces, which can then be | |
* queried by others ({ERC165Checker}). | |
* | |
* For an implementation, see {ERC165}. | |
*/ | |
interface IERC165 { | |
/** | |
* @dev Returns true if this contract implements the interface defined by | |
* `interfaceId`. See the corresponding | |
* https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section] | |
* to learn more about how these ids are created. | |
* | |
* This function call must use less than 30 000 gas. | |
*/ | |
function supportsInterface(bytes4 interfaceId) external view returns (bool); | |
} |
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{ | |
"overrides": [ | |
{ | |
"files": "*.sol", | |
"options": { | |
"printWidth": 80, | |
"tabWidth": 4, | |
"useTabs": false, | |
"singleQuote": false, | |
"bracketSpacing": false | |
} | |
}, | |
{ | |
"files": "*.yml", | |
"options": {} | |
}, | |
{ | |
"files": "*.yaml", | |
"options": {} | |
}, | |
{ | |
"files": "*.toml", | |
"options": {} | |
}, | |
{ | |
"files": "*.json", | |
"options": {} | |
}, | |
{ | |
"files": "*.js", | |
"options": {} | |
}, | |
{ | |
"files": "*.ts", | |
"options": {} | |
} | |
] | |
} |
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REMIX DEFAULT WORKSPACE | |
Remix default workspace is present when: | |
i. Remix loads for the very first time | |
ii. A new workspace is created with 'Default' template | |
iii. There are no files existing in the File Explorer | |
This workspace contains 3 directories: | |
1. 'contracts': Holds three contracts with increasing levels of complexity. | |
2. 'scripts': Contains four typescript files to deploy a contract. It is explained below. | |
3. 'tests': Contains one Solidity test file for 'Ballot' contract & one JS test file for 'Storage' contract. | |
SCRIPTS | |
The 'scripts' folder has four typescript files which help to deploy the 'Storage' contract using 'web3.js' and 'ethers.js' libraries. | |
For the deployment of any other contract, just update the contract's name from 'Storage' to the desired contract and provide constructor arguments accordingly | |
in the file `deploy_with_ethers.ts` or `deploy_with_web3.ts` | |
In the 'tests' folder there is a script containing Mocha-Chai unit tests for 'Storage' contract. | |
To run a script, right click on file name in the file explorer and click 'Run'. Remember, Solidity file must already be compiled. | |
Output from script will appear in remix terminal. | |
Please note, require/import is supported in a limited manner for Remix supported modules. | |
For now, modules supported by Remix are ethers, web3, swarmgw, chai, multihashes, remix and hardhat only for hardhat.ethers object/plugin. | |
For unsupported modules, an error like this will be thrown: '<module_name> module require is not supported by Remix IDE' will be shown. |
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