SafeERC20.sol

// SPDX-License-Identifier: ISC
pragma solidity ^0.8.19;

import {IERC20} from "@openzeppelin/contracts/interfaces/IERC20.sol";
import {SafeERC20 as OZSafeERC20} from "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";

// solhint-disable avoid-low-level-calls
// solhint-disable max-line-length

/// @title SafeERC20 provides helper functions for safe transfers as well as safe metadata access
/// @author Library originally written by @Boring_Crypto github.com/boring_crypto, modified by Drake Evans (Frax Finance) github.com/drakeevans
/// @dev original: https://github.com/boringcrypto/BoringSolidity/blob/fed25c5d43cb7ce20764cd0b838e21a02ea162e9/contracts/libraries/BoringERC20.sol
library SafeERC20 {
    bytes4 private constant SIG_SYMBOL = 0x95d89b41; // symbol()
    bytes4 private constant SIG_NAME = 0x06fdde03; // name()
    bytes4 private constant SIG_DECIMALS = 0x313ce567; // decimals()

    function returnDataToString(bytes memory data) internal pure returns (string memory) {
        if (data.length >= 64) {
            return abi.decode(data, (string));
        } else if (data.length == 32) {
            uint8 i = 0;
            while (i < 32 && data[i] != 0) {
                i++;
            }
            bytes memory bytesArray = new bytes(i);
            for (i = 0; i < 32 && data[i] != 0; i++) {
                bytesArray[i] = data[i];
            }
            return string(bytesArray);
        } else {
            return "???";
        }
    }

    /// @notice Provides a safe ERC20.symbol version which returns '???' as fallback string.
    /// @param token The address of the ERC-20 token contract.
    /// @return (string) Token symbol.
    function safeSymbol(IERC20 token) internal view returns (string memory) {
        (bool success, bytes memory data) = address(token).staticcall(abi.encodeWithSelector(SIG_SYMBOL));
        return success ? returnDataToString(data) : "???";
    }

    /// @notice Provides a safe ERC20.name version which returns '???' as fallback string.
    /// @param token The address of the ERC-20 token contract.
    /// @return (string) Token name.
    function safeName(IERC20 token) internal view returns (string memory) {
        (bool success, bytes memory data) = address(token).staticcall(abi.encodeWithSelector(SIG_NAME));
        return success ? returnDataToString(data) : "???";
    }

    /// @notice Provides a safe ERC20.decimals version which returns '18' as fallback value.
    /// @param token The address of the ERC-20 token contract.
    /// @return (uint8) Token decimals.
    function safeDecimals(IERC20 token) internal view returns (uint8) {
        (bool success, bytes memory data) = address(token).staticcall(abi.encodeWithSelector(SIG_DECIMALS));
        return success && data.length == 32 ? abi.decode(data, (uint8)) : 18;
    }

    function safeTransfer(IERC20 token, address to, uint256 value) internal {
        OZSafeERC20.safeTransfer(token, to, value);
    }

    function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal {
        OZSafeERC20.safeTransferFrom(token, from, to, value);
    }
}