// SPDX-License-Identifier: AGPL-3.0-only pragma solidity >=0.8.0; import {ERC20} from "../tokens/ERC20.sol"; import {SafeTransferLib} from "../utils/SafeTransferLib.sol"; import {FixedPointMathLib} from "../utils/FixedPointMathLib.sol"; /// @notice Minimal ERC4626 tokenized Vault implementation. /// @author Solmate (https://github.com/Rari-Capital/solmate/blob/main/src/mixins/ERC4626.sol) abstract contract ERC4626 is ERC20 { using SafeTransferLib for ERC20; using FixedPointMathLib for uint256; /*////////////////////////////////////////////////////////////// EVENTS //////////////////////////////////////////////////////////////*/ event Deposit( address indexed caller, address indexed owner, uint256 assets, uint256 shares ); event Withdraw( address indexed caller, address indexed receiver, address indexed owner, uint256 assets, uint256 shares ); /*////////////////////////////////////////////////////////////// IMMUTABLES //////////////////////////////////////////////////////////////*/ ERC20 public immutable asset; constructor( ERC20 _asset, string memory _name, string memory _symbol ) ERC20(_name, _symbol, _asset.decimals()) { asset = _asset; } /*////////////////////////////////////////////////////////////// DEPOSIT/WITHDRAWAL LOGIC //////////////////////////////////////////////////////////////*/ function deposit(uint256 assets, address receiver) public virtual returns (uint256 shares) { // Check for rounding error since we round down in previewDeposit. require((shares = previewDeposit(assets)) != 0, "ZERO_SHARES"); // Need to transfer before minting or ERC777s could reenter. asset.safeTransferFrom(msg.sender, address(this), assets); _mint(receiver, shares); emit Deposit(msg.sender, receiver, assets, shares); afterDeposit(assets, shares); } function mint(uint256 shares, address receiver) public virtual returns (uint256 assets) { assets = previewMint(shares); // No need to check for rounding error, previewMint rounds up. // Need to transfer before minting or ERC777s could reenter. asset.safeTransferFrom(msg.sender, address(this), assets); _mint(receiver, shares); emit Deposit(msg.sender, receiver, assets, shares); afterDeposit(assets, shares); } function withdraw( uint256 assets, address receiver, address owner ) public virtual returns (uint256 shares) { shares = previewWithdraw(assets); // No need to check for rounding error, previewWithdraw rounds up. if (msg.sender != owner) { uint256 allowed = allowance[owner][msg.sender]; // Saves gas for limited approvals. if (allowed != type(uint256).max) allowance[owner][msg.sender] = allowed - shares; } beforeWithdraw(assets, shares); _burn(owner, shares); emit Withdraw(msg.sender, receiver, owner, assets, shares); asset.safeTransfer(receiver, assets); } function redeem( uint256 shares, address receiver, address owner ) public virtual returns (uint256 assets) { if (msg.sender != owner) { uint256 allowed = allowance[owner][msg.sender]; // Saves gas for limited approvals. if (allowed != type(uint256).max) allowance[owner][msg.sender] = allowed - shares; } // Check for rounding error since we round down in previewRedeem. require((assets = previewRedeem(shares)) != 0, "ZERO_ASSETS"); beforeWithdraw(assets, shares); _burn(owner, shares); emit Withdraw(msg.sender, receiver, owner, assets, shares); asset.safeTransfer(receiver, assets); } /*////////////////////////////////////////////////////////////// ACCOUNTING LOGIC //////////////////////////////////////////////////////////////*/ function totalAssets() public view virtual returns (uint256); function convertToShares(uint256 assets) public view virtual returns (uint256) { uint256 supply = totalSupply; // Saves an extra SLOAD if totalSupply is non-zero. return supply == 0 ? assets : assets.mulDivDown(supply, totalAssets()); } function convertToAssets(uint256 shares) public view virtual returns (uint256) { uint256 supply = totalSupply; // Saves an extra SLOAD if totalSupply is non-zero. return supply == 0 ? shares : shares.mulDivDown(totalAssets(), supply); } function previewDeposit(uint256 assets) public view virtual returns (uint256) { return convertToShares(assets); } function previewMint(uint256 shares) public view virtual returns (uint256) { uint256 supply = totalSupply; // Saves an extra SLOAD if totalSupply is non-zero. return supply == 0 ? shares : shares.mulDivUp(totalAssets(), supply); } function previewWithdraw(uint256 assets) public view virtual returns (uint256) { uint256 supply = totalSupply; // Saves an extra SLOAD if totalSupply is non-zero. return supply == 0 ? assets : assets.mulDivUp(supply, totalAssets()); } function previewRedeem(uint256 shares) public view virtual returns (uint256) { return convertToAssets(shares); } /*////////////////////////////////////////////////////////////// DEPOSIT/WITHDRAWAL LIMIT LOGIC //////////////////////////////////////////////////////////////*/ function maxDeposit(address) public view virtual returns (uint256) { return type(uint256).max; } function maxMint(address) public view virtual returns (uint256) { return type(uint256).max; } function maxWithdraw(address owner) public view virtual returns (uint256) { return convertToAssets(balanceOf[owner]); } function maxRedeem(address owner) public view virtual returns (uint256) { return balanceOf[owner]; } /*////////////////////////////////////////////////////////////// INTERNAL HOOKS LOGIC //////////////////////////////////////////////////////////////*/ function beforeWithdraw(uint256 assets, uint256 shares) internal virtual {} function afterDeposit(uint256 assets, uint256 shares) internal virtual {} }
0.7.1