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contracts/lib/ReentrancyGuard.sol

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+/*
+
+    Copyright 2020 DODO ZOO.
+    SPDX-License-Identifier: Apache-2.0
+
+*/
+
+pragma solidity 0.6.9;
+pragma experimental ABIEncoderV2;
+
+import {Types} from "./Types.sol";
+
+/**
+ * @title ReentrancyGuard
+ * @author DODO Breeder
+ *
+ * @notice Protect functions from Reentrancy Attack
+ */
+contract ReentrancyGuard {
+    Types.EnterStatus private _ENTER_STATUS_;
+
+    constructor() internal {
+        _ENTER_STATUS_ = Types.EnterStatus.NOT_ENTERED;
+    }
+
+    modifier preventReentrant() {
+        require(_ENTER_STATUS_ != Types.EnterStatus.ENTERED, "ReentrancyGuard: reentrant call");
+        _ENTER_STATUS_ = Types.EnterStatus.ENTERED;
+        _;
+        _ENTER_STATUS_ = Types.EnterStatus.NOT_ENTERED;
+    }
+}