125 lines
4.3 KiB
Solidity
125 lines
4.3 KiB
Solidity
// SPDX-License-Identifier: Apache-2.0
|
|
/*
|
|
|
|
Copyright 2020 ZeroEx Intl.
|
|
|
|
Licensed under the Apache License, Version 2.0 (the "License");
|
|
you may not use this file except in compliance with the License.
|
|
You may obtain a copy of the License at
|
|
|
|
http://www.apache.org/licenses/LICENSE-2.0
|
|
|
|
Unless required by applicable law or agreed to in writing, software
|
|
distributed under the License is distributed on an "AS IS" BASIS,
|
|
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
See the License for the specific language governing permissions and
|
|
limitations under the License.
|
|
|
|
*/
|
|
|
|
pragma solidity ^0.6;
|
|
pragma experimental ABIEncoderV2;
|
|
|
|
import "@0x/contracts-utils/contracts/src/v06/LibBytesV06.sol";
|
|
|
|
|
|
contract TwoHopSampler {
|
|
using LibBytesV06 for bytes;
|
|
|
|
struct HopInfo {
|
|
uint256 sourceIndex;
|
|
bytes returnData;
|
|
}
|
|
|
|
function sampleTwoHopSell(
|
|
bytes[] memory firstHopCalls,
|
|
bytes[] memory secondHopCalls,
|
|
uint256 sellAmount
|
|
)
|
|
public
|
|
returns (
|
|
HopInfo memory firstHop,
|
|
HopInfo memory secondHop,
|
|
uint256 buyAmount
|
|
)
|
|
{
|
|
uint256 intermediateAssetAmount = 0;
|
|
for (uint256 i = 0; i != firstHopCalls.length; ++i) {
|
|
firstHopCalls[i].writeUint256(firstHopCalls[i].length - 32, sellAmount);
|
|
(bool didSucceed, bytes memory returnData) = address(this).call(firstHopCalls[i]);
|
|
if (didSucceed) {
|
|
uint256 amount = returnData.readUint256(returnData.length - 32);
|
|
if (amount > intermediateAssetAmount) {
|
|
intermediateAssetAmount = amount;
|
|
firstHop.sourceIndex = i;
|
|
firstHop.returnData = returnData;
|
|
}
|
|
}
|
|
}
|
|
if (intermediateAssetAmount == 0) {
|
|
return (firstHop, secondHop, buyAmount);
|
|
}
|
|
for (uint256 j = 0; j != secondHopCalls.length; ++j) {
|
|
secondHopCalls[j].writeUint256(secondHopCalls[j].length - 32, intermediateAssetAmount);
|
|
(bool didSucceed, bytes memory returnData) = address(this).call(secondHopCalls[j]);
|
|
if (didSucceed) {
|
|
uint256 amount = returnData.readUint256(returnData.length - 32);
|
|
if (amount > buyAmount) {
|
|
buyAmount = amount;
|
|
secondHop.sourceIndex = j;
|
|
secondHop.returnData = returnData;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
function sampleTwoHopBuy(
|
|
bytes[] memory firstHopCalls,
|
|
bytes[] memory secondHopCalls,
|
|
uint256 buyAmount
|
|
)
|
|
public
|
|
returns (
|
|
HopInfo memory firstHop,
|
|
HopInfo memory secondHop,
|
|
uint256 sellAmount
|
|
)
|
|
{
|
|
sellAmount = uint256(-1);
|
|
uint256 intermediateAssetAmount = uint256(-1);
|
|
for (uint256 j = 0; j != secondHopCalls.length; ++j) {
|
|
secondHopCalls[j].writeUint256(secondHopCalls[j].length - 32, buyAmount);
|
|
(bool didSucceed, bytes memory returnData) = address(this).call(secondHopCalls[j]);
|
|
if (didSucceed) {
|
|
uint256 amount = returnData.readUint256(returnData.length - 32);
|
|
if (
|
|
amount > 0 &&
|
|
amount < intermediateAssetAmount
|
|
) {
|
|
intermediateAssetAmount = amount;
|
|
secondHop.sourceIndex = j;
|
|
secondHop.returnData = returnData;
|
|
}
|
|
}
|
|
}
|
|
if (intermediateAssetAmount == uint256(-1)) {
|
|
return (firstHop, secondHop, sellAmount);
|
|
}
|
|
for (uint256 i = 0; i != firstHopCalls.length; ++i) {
|
|
firstHopCalls[i].writeUint256(firstHopCalls[i].length - 32, intermediateAssetAmount);
|
|
(bool didSucceed, bytes memory returnData) = address(this).call(firstHopCalls[i]);
|
|
if (didSucceed) {
|
|
uint256 amount = returnData.readUint256(returnData.length - 32);
|
|
if (
|
|
amount > 0 &&
|
|
amount < sellAmount
|
|
) {
|
|
sellAmount = amount;
|
|
firstHop.sourceIndex = i;
|
|
firstHop.returnData = returnData;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|