Contract Source Code:
/*
OwnerController
https://github.com/gysr-io/core
SPDX-License-Identifier: MIT
*/
pragma solidity 0.8.4;
/**
* @title Owner controller
*
* @notice this base contract implements an owner-controller access model.
*
* @dev the contract is an adapted version of the OpenZeppelin Ownable contract.
* It allows the owner to designate an additional account as the controller to
* perform restricted operations.
*
* Other changes include supporting role verification with a require method
* in addition to the modifier option, and removing some unneeded functionality.
*
* Original contract here:
* https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/access/Ownable.sol
*/
contract OwnerController {
address private _owner;
address private _controller;
event OwnershipTransferred(
address indexed previousOwner,
address indexed newOwner
);
event ControlTransferred(
address indexed previousController,
address indexed newController
);
constructor() {
_owner = msg.sender;
_controller = msg.sender;
emit OwnershipTransferred(address(0), _owner);
emit ControlTransferred(address(0), _owner);
}
/**
* @dev Returns the address of the current owner.
*/
function owner() public view returns (address) {
return _owner;
}
/**
* @dev Returns the address of the current controller.
*/
function controller() public view returns (address) {
return _controller;
}
/**
* @dev Modifier that throws if called by any account other than the owner.
*/
modifier onlyOwner() {
require(_owner == msg.sender, "oc1");
_;
}
/**
* @dev Modifier that throws if called by any account other than the controller.
*/
modifier onlyController() {
require(_controller == msg.sender, "oc2");
_;
}
/**
* @dev Throws if called by any account other than the owner.
*/
function requireOwner() internal view {
require(_owner == msg.sender, "oc1");
}
/**
* @dev Throws if called by any account other than the controller.
*/
function requireController() internal view {
require(_controller == msg.sender, "oc2");
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`). This can
* include renouncing ownership by transferring to the zero address.
* Can only be called by the current owner.
*/
function transferOwnership(address newOwner) public virtual {
requireOwner();
require(newOwner != address(0), "oc3");
emit OwnershipTransferred(_owner, newOwner);
_owner = newOwner;
}
/**
* @dev Transfers control of the contract to a new account (`newController`).
* Can only be called by the owner.
*/
function transferControl(address newController) public virtual {
requireOwner();
require(newController != address(0), "oc4");
emit ControlTransferred(_controller, newController);
_controller = newController;
}
}
/*
Pool
https://github.com/gysr-io/core
SPDX-License-Identifier: MIT
*/
pragma solidity 0.8.4;
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
import "@openzeppelin/contracts/security/ReentrancyGuard.sol";
import "./interfaces/IPool.sol";
import "./interfaces/IPoolFactory.sol";
import "./interfaces/IStakingModule.sol";
import "./interfaces/IRewardModule.sol";
import "./interfaces/IEvents.sol";
import "./OwnerController.sol";
/**
* @title Pool
*
* @notice this implements the GYSR core Pool contract. It supports generalized
* incentive mechanisms through a modular architecture, where
* staking and reward logic is contained in child contracts.
*/
contract Pool is IPool, IEvents, ReentrancyGuard, OwnerController {
using SafeERC20 for IERC20;
// constants
uint256 public constant DECIMALS = 18;
// modules
IStakingModule private immutable _staking;
IRewardModule private immutable _reward;
// gysr fields
IERC20 private immutable _gysr;
IPoolFactory private immutable _factory;
uint256 private _gysrVested;
/**
* @param staking_ the staking module address
* @param reward_ the reward module address
* @param gysr_ address for GYSR token
* @param factory_ address for parent factory
*/
constructor(
address staking_,
address reward_,
address gysr_,
address factory_
) {
_staking = IStakingModule(staking_);
_reward = IRewardModule(reward_);
_gysr = IERC20(gysr_);
_factory = IPoolFactory(factory_);
}
// -- IPool --------------------------------------------------------------
/**
* @inheritdoc IPool
*/
function stakingTokens() external view override returns (address[] memory) {
return _staking.tokens();
}
/**
* @inheritdoc IPool
*/
function rewardTokens() external view override returns (address[] memory) {
return _reward.tokens();
}
/**
* @inheritdoc IPool
*/
function stakingBalances(address user)
external
view
override
returns (uint256[] memory)
{
return _staking.balances(user);
}
/**
* @inheritdoc IPool
*/
function stakingTotals() external view override returns (uint256[] memory) {
return _staking.totals();
}
/**
* @inheritdoc IPool
*/
function rewardBalances()
external
view
override
returns (uint256[] memory)
{
return _reward.balances();
}
/**
* @inheritdoc IPool
*/
function usage() external view override returns (uint256) {
return _reward.usage();
}
/**
* @inheritdoc IPool
*/
function stakingModule() external view override returns (address) {
return address(_staking);
}
/**
* @inheritdoc IPool
*/
function rewardModule() external view override returns (address) {
return address(_reward);
}
/**
* @inheritdoc IPool
*/
function stake(
uint256 amount,
bytes calldata stakingdata,
bytes calldata rewarddata
) external override nonReentrant {
(address account, uint256 shares) =
_staking.stake(msg.sender, amount, stakingdata);
(uint256 spent, uint256 vested) =
_reward.stake(account, msg.sender, shares, rewarddata);
_processGysr(spent, vested);
}
/**
* @inheritdoc IPool
*/
function unstake(
uint256 amount,
bytes calldata stakingdata,
bytes calldata rewarddata
) external override nonReentrant {
(address account, uint256 shares) =
_staking.unstake(msg.sender, amount, stakingdata);
(uint256 spent, uint256 vested) =
_reward.unstake(account, msg.sender, shares, rewarddata);
_processGysr(spent, vested);
}
/**
* @inheritdoc IPool
*/
function claim(
uint256 amount,
bytes calldata stakingdata,
bytes calldata rewarddata
) external override nonReentrant {
(address account, uint256 shares) =
_staking.claim(msg.sender, amount, stakingdata);
(uint256 spent, uint256 vested) =
_reward.claim(account, msg.sender, shares, rewarddata);
_processGysr(spent, vested);
}
/**
* @inheritdoc IPool
*/
function update() external override nonReentrant {
_staking.update(msg.sender);
_reward.update(msg.sender);
}
/**
* @inheritdoc IPool
*/
function clean() external override nonReentrant {
requireController();
_staking.clean();
_reward.clean();
}
/**
* @inheritdoc IPool
*/
function gysrBalance() external view override returns (uint256) {
return _gysrVested;
}
/**
* @inheritdoc IPool
*/
function withdraw(uint256 amount) external override {
requireController();
require(amount > 0, "p1");
require(amount <= _gysrVested, "p2");
// do transfer
_gysr.safeTransfer(msg.sender, amount);
_gysrVested = _gysrVested - amount;
emit GysrWithdrawn(amount);
}
/**
* @notice transfer control of the Pool and modules to another account
* @param newController address of new controller
*/
function transferControl(address newController) public override {
super.transferControl(newController);
_staking.transferControl(newController);
_reward.transferControl(newController);
}
// -- Pool internal -----------------------------------------------------
/**
* @dev private method to process GYSR spending and vesting
* @param spent number of tokens to unstake
* @param vested data passed to staking module
*/
function _processGysr(uint256 spent, uint256 vested) private {
// spending
if (spent > 0) {
_gysr.safeTransferFrom(msg.sender, address(this), spent);
}
// vesting
if (vested > 0) {
uint256 fee = (vested * _factory.fee()) / 10**DECIMALS;
if (fee > 0) {
_gysr.safeTransfer(_factory.treasury(), fee);
}
_gysrVested = _gysrVested + vested - fee;
}
}
}
/*
IEvents
https://github.com/gysr-io/core
SPDX-License-Identifier: MIT
*/
pragma solidity 0.8.4;
/**
* @title GYSR event system
*
* @notice common interface to define GYSR event system
*/
interface IEvents {
// staking
event Staked(
address indexed user,
address indexed token,
uint256 amount,
uint256 shares
);
event Unstaked(
address indexed user,
address indexed token,
uint256 amount,
uint256 shares
);
event Claimed(
address indexed user,
address indexed token,
uint256 amount,
uint256 shares
);
// rewards
event RewardsDistributed(
address indexed user,
address indexed token,
uint256 amount,
uint256 shares
);
event RewardsFunded(
address indexed token,
uint256 amount,
uint256 shares,
uint256 timestamp
);
event RewardsUnlocked(address indexed token, uint256 shares);
event RewardsExpired(
address indexed token,
uint256 amount,
uint256 shares,
uint256 timestamp
);
// gysr
event GysrSpent(address indexed user, uint256 amount);
event GysrVested(address indexed user, uint256 amount);
event GysrWithdrawn(uint256 amount);
}
/*
IPool
https://github.com/gysr-io/core
SPDX-License-Identifier: MIT
*/
pragma solidity 0.8.4;
/**
* @title Pool interface
*
* @notice this defines the core Pool contract interface
*/
interface IPool {
/**
* @return staking tokens for Pool
*/
function stakingTokens() external view returns (address[] memory);
/**
* @return reward tokens for Pool
*/
function rewardTokens() external view returns (address[] memory);
/**
* @return staking balances for user
*/
function stakingBalances(address user)
external
view
returns (uint256[] memory);
/**
* @return total staking balances for Pool
*/
function stakingTotals() external view returns (uint256[] memory);
/**
* @return reward balances for Pool
*/
function rewardBalances() external view returns (uint256[] memory);
/**
* @return GYSR usage ratio for Pool
*/
function usage() external view returns (uint256);
/**
* @return address of staking module
*/
function stakingModule() external view returns (address);
/**
* @return address of reward module
*/
function rewardModule() external view returns (address);
/**
* @notice stake asset and begin earning rewards
* @param amount number of tokens to unstake
* @param stakingdata data passed to staking module
* @param rewarddata data passed to reward module
*/
function stake(
uint256 amount,
bytes calldata stakingdata,
bytes calldata rewarddata
) external;
/**
* @notice unstake asset and claim rewards
* @param amount number of tokens to unstake
* @param stakingdata data passed to staking module
* @param rewarddata data passed to reward module
*/
function unstake(
uint256 amount,
bytes calldata stakingdata,
bytes calldata rewarddata
) external;
/**
* @notice claim rewards without unstaking
* @param amount number of tokens to claim against
* @param stakingdata data passed to staking module
* @param rewarddata data passed to reward module
*/
function claim(
uint256 amount,
bytes calldata stakingdata,
bytes calldata rewarddata
) external;
/**
* @notice method called ad hoc to update user accounting
*/
function update() external;
/**
* @notice method called ad hoc to clean up and perform additional accounting
*/
function clean() external;
/**
* @return gysr balance available for withdrawal
*/
function gysrBalance() external view returns (uint256);
/**
* @notice withdraw GYSR tokens applied during unstaking
* @param amount number of GYSR to withdraw
*/
function withdraw(uint256 amount) external;
}
/*
IPoolFactory
https://github.com/gysr-io/core
SPDX-License-Identifier: MIT
*/
pragma solidity 0.8.4;
/**
* @title Pool factory interface
*
* @notice this defines the Pool factory interface, primarily intended for
* the Pool contract to interact with
*/
interface IPoolFactory {
/**
* @return GYSR treasury address
*/
function treasury() external view returns (address);
/**
* @return GYSR spending fee
*/
function fee() external view returns (uint256);
}
/*
IRewardModule
https://github.com/gysr-io/core
SPDX-License-Identifier: MIT
*/
pragma solidity 0.8.4;
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "./IEvents.sol";
import "../OwnerController.sol";
/**
* @title Reward module interface
*
* @notice this contract defines the common interface that any reward module
* must implement to be compatible with the modular Pool architecture.
*/
abstract contract IRewardModule is OwnerController, IEvents {
// constants
uint256 public constant DECIMALS = 18;
/**
* @return array of reward tokens
*/
function tokens() external view virtual returns (address[] memory);
/**
* @return array of reward token balances
*/
function balances() external view virtual returns (uint256[] memory);
/**
* @return GYSR usage ratio for reward module
*/
function usage() external view virtual returns (uint256);
/**
* @return address of module factory
*/
function factory() external view virtual returns (address);
/**
* @notice perform any necessary accounting for new stake
* @param account address of staking account
* @param user address of user
* @param shares number of new shares minted
* @param data addtional data
* @return amount of gysr spent
* @return amount of gysr vested
*/
function stake(
address account,
address user,
uint256 shares,
bytes calldata data
) external virtual returns (uint256, uint256);
/**
* @notice reward user and perform any necessary accounting for unstake
* @param account address of staking account
* @param user address of user
* @param shares number of shares burned
* @param data additional data
* @return amount of gysr spent
* @return amount of gysr vested
*/
function unstake(
address account,
address user,
uint256 shares,
bytes calldata data
) external virtual returns (uint256, uint256);
/**
* @notice reward user and perform and necessary accounting for existing stake
* @param account address of staking account
* @param user address of user
* @param shares number of shares being claimed against
* @param data addtional data
* @return amount of gysr spent
* @return amount of gysr vested
*/
function claim(
address account,
address user,
uint256 shares,
bytes calldata data
) external virtual returns (uint256, uint256);
/**
* @notice method called by anyone to update accounting
* @param user address of user for update
* @dev will only be called ad hoc and should not contain essential logic
*/
function update(address user) external virtual;
/**
* @notice method called by owner to clean up and perform additional accounting
* @dev will only be called ad hoc and should not contain any essential logic
*/
function clean() external virtual;
}
/*
IStakingModule
https://github.com/gysr-io/core
SPDX-License-Identifier: MIT
*/
pragma solidity 0.8.4;
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "./IEvents.sol";
import "../OwnerController.sol";
/**
* @title Staking module interface
*
* @notice this contract defines the common interface that any staking module
* must implement to be compatible with the modular Pool architecture.
*/
abstract contract IStakingModule is OwnerController, IEvents {
// constants
uint256 public constant DECIMALS = 18;
/**
* @return array of staking tokens
*/
function tokens() external view virtual returns (address[] memory);
/**
* @notice get balance of user
* @param user address of user
* @return balances of each staking token
*/
function balances(address user)
external
view
virtual
returns (uint256[] memory);
/**
* @return address of module factory
*/
function factory() external view virtual returns (address);
/**
* @notice get total staked amount
* @return totals for each staking token
*/
function totals() external view virtual returns (uint256[] memory);
/**
* @notice stake an amount of tokens for user
* @param user address of user
* @param amount number of tokens to stake
* @param data additional data
* @return address of staking account
* @return number of shares minted for stake
*/
function stake(
address user,
uint256 amount,
bytes calldata data
) external virtual returns (address, uint256);
/**
* @notice unstake an amount of tokens for user
* @param user address of user
* @param amount number of tokens to unstake
* @param data additional data
* @return address of staking account
* @return number of shares burned for unstake
*/
function unstake(
address user,
uint256 amount,
bytes calldata data
) external virtual returns (address, uint256);
/**
* @notice quote the share value for an amount of tokens without unstaking
* @param user address of user
* @param amount number of tokens to claim with
* @param data additional data
* @return address of staking account
* @return number of shares that the claim amount is worth
*/
function claim(
address user,
uint256 amount,
bytes calldata data
) external virtual returns (address, uint256);
/**
* @notice method called by anyone to update accounting
* @param user address of user for update
* @dev will only be called ad hoc and should not contain essential logic
*/
function update(address user) external virtual;
/**
* @notice method called by owner to clean up and perform additional accounting
* @dev will only be called ad hoc and should not contain any essential logic
*/
function clean() external virtual;
}
// SPDX-License-Identifier: MIT
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 make it call a
* `private` function that does the actual work.
*/
modifier nonReentrant() {
// On the first call to nonReentrant, _notEntered will be true
require(_status != _ENTERED, "ReentrancyGuard: reentrant call");
// Any calls to nonReentrant after this point will fail
_status = _ENTERED;
_;
// By storing the original value once again, a refund is triggered (see
// https://eips.ethereum.org/EIPS/eip-2200)
_status = _NOT_ENTERED;
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
/**
* @dev Interface of the ERC20 standard as defined in the EIP.
*/
interface IERC20 {
/**
* @dev Returns the amount of tokens in existence.
*/
function totalSupply() external view returns (uint256);
/**
* @dev Returns the amount of tokens owned by `account`.
*/
function balanceOf(address account) external view returns (uint256);
/**
* @dev Moves `amount` tokens from the caller's account to `recipient`.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/
function transfer(address recipient, uint256 amount) external returns (bool);
/**
* @dev Returns the remaining number of tokens that `spender` will be
* allowed to spend on behalf of `owner` through {transferFrom}. This is
* zero by default.
*
* This value changes when {approve} or {transferFrom} are called.
*/
function allowance(address owner, address spender) external view returns (uint256);
/**
* @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* IMPORTANT: Beware that changing an allowance with this method brings the risk
* that someone may use both the old and the new allowance by unfortunate
* transaction ordering. One possible solution to mitigate this race
* condition is to first reduce the spender's allowance to 0 and set the
* desired value afterwards:
* https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
*
* Emits an {Approval} event.
*/
function approve(address spender, uint256 amount) external returns (bool);
/**
* @dev Moves `amount` tokens from `sender` to `recipient` using the
* allowance mechanism. `amount` is then deducted from the caller's
* allowance.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/
function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);
/**
* @dev Emitted when `value` tokens are moved from one account (`from`) to
* another (`to`).
*
* Note that `value` may be zero.
*/
event Transfer(address indexed from, address indexed to, uint256 value);
/**
* @dev Emitted when the allowance of a `spender` for an `owner` is set by
* a call to {approve}. `value` is the new allowance.
*/
event Approval(address indexed owner, address indexed spender, uint256 value);
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import "../IERC20.sol";
import "../../../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;
function safeTransfer(IERC20 token, address to, uint256 value) internal {
_callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
}
function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal {
_callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
}
/**
* @dev Deprecated. This function has issues similar to the ones found in
* {IERC20-approve}, and its usage is discouraged.
*
* Whenever possible, use {safeIncreaseAllowance} and
* {safeDecreaseAllowance} instead.
*/
function safeApprove(IERC20 token, address spender, uint256 value) internal {
// safeApprove should only be called when setting an initial allowance,
// or when resetting it to zero. To increase and decrease it, use
// 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
// solhint-disable-next-line max-line-length
require((value == 0) || (token.allowance(address(this), spender) == 0),
"SafeERC20: approve from non-zero to non-zero allowance"
);
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
}
function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
uint256 newAllowance = token.allowance(address(this), spender) + value;
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
}
function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal {
unchecked {
uint256 oldAllowance = token.allowance(address(this), spender);
require(oldAllowance >= value, "SafeERC20: decreased allowance below zero");
uint256 newAllowance = oldAllowance - value;
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
}
}
/**
* @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
* on the return value: the return value is optional (but if data is returned, it must not be false).
* @param token The token targeted by the call.
* @param data The call data (encoded using abi.encode or one of its variants).
*/
function _callOptionalReturn(IERC20 token, bytes memory data) private {
// We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
// we're implementing it ourselves. 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, "SafeERC20: low-level call failed");
if (returndata.length > 0) { // Return data is optional
// solhint-disable-next-line max-line-length
require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
}
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
/**
* @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) {
// This method relies on extcodesize, which returns 0 for contracts in
// construction, since the code is only stored at the end of the
// constructor execution.
uint256 size;
// solhint-disable-next-line no-inline-assembly
assembly { size := extcodesize(account) }
return size > 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://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");
require(isContract(target), "Address: call to non-contract");
// solhint-disable-next-line avoid-low-level-calls
(bool success, bytes memory returndata) = target.call{ value: value }(data);
return _verifyCallResult(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) {
require(isContract(target), "Address: static call to non-contract");
// solhint-disable-next-line avoid-low-level-calls
(bool success, bytes memory returndata) = target.staticcall(data);
return _verifyCallResult(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) {
require(isContract(target), "Address: delegate call to non-contract");
// solhint-disable-next-line avoid-low-level-calls
(bool success, bytes memory returndata) = target.delegatecall(data);
return _verifyCallResult(success, returndata, errorMessage);
}
function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private pure returns(bytes memory) {
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);
}
}
}
}