PancakeInterfaceMulticallV2

// SPDX-License-Identifier: MIT
pragma solidity =0.7.6;
pragma abicoder v2;

/// @notice A fork of MultiCall with gas limit
contract PancakeInterfaceMulticallV2 {
    struct Call {
        address target;
        uint256 gasLimit;
        bytes callData;
    }

    struct Result {
        bool success;
        uint256 gasUsed;
        bytes returnData;
    }

    function multicall(Call[] memory calls) public returns (uint256 blockNumber, Result[] memory returnData) {
        blockNumber = block.number;
        returnData = new Result[](calls.length);

        for (uint256 i = 0; i < calls.length; i++) {
            (address target, uint256 gasLimit, bytes memory callData) =
                (calls[i].target, calls[i].gasLimit, calls[i].callData);

            uint256 gasLeftBefore = gasleft();
            (bool success, bytes memory ret) = target.call{gas: gasLimit}(callData);
            uint256 gasUsed = gasLeftBefore - gasleft();
            returnData[i] = Result(success, gasUsed, ret);
        }
    }

    function multicallWithGasLimitation(Call[] memory calls, uint256 gasBuffer)
        public
        returns (uint256 blockNumber, Result[] memory returnData, uint256 lastSuccessIndex)
    {
        blockNumber = block.number;
        returnData = new Result[](calls.length);

        for (uint256 i = 0; i < calls.length; i++) {
            (address target, uint256 gasLimit, bytes memory callData) =
                (calls[i].target, calls[i].gasLimit, calls[i].callData);

            uint256 gasLeftBefore = gasleft();
            (bool success, bytes memory ret) = target.call{gas: gasLimit}(callData);
            uint256 gasUsed = gasLeftBefore - gasleft();
            returnData[i] = Result(success, gasUsed, ret);

            if (gasleft() < gasBuffer) {
                return (blockNumber, returnData, i);
            }
        }

        return (blockNumber, returnData, calls.length - 1);
    }

    function gaslimit() external view returns (uint256) {
        return block.gaslimit;
    }

    function gasLeft() external view returns (uint256) {
        return gasleft();
    }
}