Merge 03445c5 into b6ee39d

sushiswap · Jul 28, 2022 · b1bbb2a · b1bbb2a
2 parents b6ee39d + 03445c5
commit b1bbb2a
Showing 1 changed file with 41 additions and 0 deletions.
diff --git a/contracts/utils/Domain.sol b/contracts/utils/Domain.sol
@@ -0,0 +1,41 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+pragma solidity 0.8.10;
+
+abstract contract Domain {
+    /*//////////////////////////////////////////////////////////////
+                        DOMAIN STORAGE/LOGIC
+    //////////////////////////////////////////////////////////////*/
+
+    uint256 internal immutable INITIAL_CHAIN_ID;
+
+    bytes32 internal immutable INITIAL_DOMAIN_SEPARATOR;
+
+    mapping(address => uint256) public nonces;
+
+    function DOMAIN_SEPARATOR() public view virtual returns (bytes32) {
+        return block.chainid == INITIAL_CHAIN_ID ? INITIAL_DOMAIN_SEPARATOR : computeDomainSeparator();
+    }
+
+    function computeDomainSeparator() internal view virtual returns (bytes32) {
+        return
+            keccak256(
+                abi.encode(
+                    keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)"),
+                    keccak256(bytes("Domain")),
+                    keccak256("1"),
+                    block.chainid,
+                    address(this)
+                )
+            );
+    }
+
+    /*//////////////////////////////////////////////////////////////
+                               CONSTRUCTOR
+    //////////////////////////////////////////////////////////////*/
+
+    constructor() {
+        INITIAL_CHAIN_ID = block.chainid;
+        INITIAL_DOMAIN_SEPARATOR = computeDomainSeparator();
+    }
+}