feat: add balancer v2 executor

foundry/lib/balancer-labs/v2-interfaces/contracts/pool-linear/ILinearPool.sol

@@ -0,0 +1,84 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+pragma solidity >=0.7.0 <0.9.0;
+pragma experimental ABIEncoderV2;
+
+import "../solidity-utils/openzeppelin/IERC20.sol";
+import "../vault/IBasePool.sol";
+
+interface ILinearPool is IBasePool {
+    /**
+     * @dev Returns the Pool's main token.
+     */
+    function getMainToken() external view returns (IERC20);
+
+    /**
+     * @dev Returns the Pool's wrapped token.
+     */
+    function getWrappedToken() external view returns (IERC20);
+
+    /**
+     * @dev Returns the index of the Pool's BPT in the Pool tokens array (as returned by IVault.getPoolTokens).
+     */
+    function getBptIndex() external view returns (uint256);
+
+    /**
+     * @dev Returns the index of the Pool's main token in the Pool tokens array (as returned by IVault.getPoolTokens).
+     */
+    function getMainIndex() external view returns (uint256);
+
+    /**
+     * @dev Returns the index of the Pool's wrapped token in the Pool tokens array (as returned by
+     * IVault.getPoolTokens).
+     */
+    function getWrappedIndex() external view returns (uint256);
+
+    /**
+     * @dev Returns the Pool's targets for the main token balance. These values have had the main token's scaling
+     * factor applied to them.
+     */
+    function getTargets() external view returns (uint256 lowerTarget, uint256 upperTarget);
+
+    /**
+     * @notice Set the lower and upper bounds of the zero-fee trading range for the main token balance.
+     * @dev For a new target range to be valid:
+     *      - the current balance must be between the current targets (meaning no fees are currently pending)
+     *      - the current balance must be between the new targets (meaning setting them does not create pending fees)
+     *
+     * The first requirement could be relaxed, as the LPs actually benefit from the pending fees not being paid out,
+     * but being stricter makes analysis easier at little expense.
+     *
+     * This is a permissioned function, reserved for the pool owner. It will revert when called within a Vault context
+     * (i.e. in the middle of a join or an exit).
+     *
+     * Correct behavior depends on the token balances from the Vault, which may be out of sync with the state of
+     * the pool during execution of a Vault hook.
+     *
+     * See https://forum.balancer.fi/t/reentrancy-vulnerability-scope-expanded/4345 for reference.
+     */
+    function setTargets(uint256 newLowerTarget, uint256 newUpperTarget) external;
+
+    /**
+     * @notice Set the swap fee percentage.
+     * @dev This is a permissioned function, reserved for the pool owner. It will revert when called within a Vault
+     * context (i.e. in the middle of a join or an exit).
+     *
+     * Correct behavior depends on the token balances from the Vault, which may be out of sync with the state of
+     * the pool during execution of a Vault hook.
+     *
+     * See https://forum.balancer.fi/t/reentrancy-vulnerability-scope-expanded/4345 for reference.
+     */
+    function setSwapFeePercentage(uint256 swapFeePercentage) external;
+}