Add link handshake

Vectorized · Feb 10, 2024 · 14a5885 · 14a5885
1 parent b7a8d13
commit 14a5885
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Showing 3 changed files with 28 additions and 7 deletions.
diff --git a/.gas-snapshot b/.gas-snapshot
@@ -1,9 +1,9 @@
-DN404Test:testBurnOnTransfer(uint32,address,address) (runs: 256, μ: 256757, ~: 258856)
-DN404Test:testInitialize(uint32,address) (runs: 256, μ: 95878, ~: 108419)
-DN404Test:testMintOnTransfer(uint32,address,address) (runs: 256, μ: 212464, ~: 214252)
-DN404Test:testNameAndSymbol(string,string) (runs: 256, μ: 205842, ~: 206183)
-DN404Test:testRegisterAndResolveAlias(address,address) (runs: 256, μ: 120443, ~: 120599)
-DN404Test:testTokenURI(string,uint256) (runs: 256, μ: 161329, ~: 145950)
-DN404Test:test__codesize() (gas: 17782)
+DN404Test:testBurnOnTransfer(uint32,address,address) (runs: 256, μ: 257424, ~: 259368)
+DN404Test:testInitialize(uint32,address) (runs: 256, μ: 95560, ~: 108931)
+DN404Test:testMintOnTransfer(uint32,address,address) (runs: 256, μ: 213053, ~: 214764)
+DN404Test:testNameAndSymbol(string,string) (runs: 256, μ: 206354, ~: 206695)
+DN404Test:testRegisterAndResolveAlias(address,address) (runs: 256, μ: 120599, ~: 120599)
+DN404Test:testTokenURI(string,uint256) (runs: 256, μ: 161878, ~: 146462)
+DN404Test:test__codesize() (gas: 17853)
 SoladyTest:test__codesize() (gas: 1075)
 TestPlus:test__codesize() (gas: 398)
diff --git a/src/DN404.sol b/src/DN404.sol
@@ -396,6 +396,10 @@ abstract contract DN404 {
 
             _return(uint160(_approveNFT(spender, id, msgSender)));
         }
+        // `implementsDN404()`.
+        if (fnSelector == 0xb7a94eb8) {
+            _return(1);
+        }
         _;
     }
 

diff --git a/src/DN404NonFungibleShadow.sol b/src/DN404NonFungibleShadow.sol
@@ -42,6 +42,8 @@ contract DN404NonFungibleShadow {
 
     error TokenDoesNotExist();
 
+    error CannotLink();
+
     error AlreadyLinked();
 
     error NotLinked();
@@ -321,6 +323,20 @@ contract DN404NonFungibleShadow {
             }
             if ($.sisterERC20 != address(0)) revert AlreadyLinked();
             $.sisterERC20 = msg.sender;
+            /// @solidity memory-safe-assembly
+            assembly {
+                // `implementsDN404()`.
+                mstore(0x00, 0xb7a94eb8)
+                if iszero(
+                    and(
+                        and(eq(mload(0x00), 1), gt(returndatasize(), 0x1f)),
+                        staticcall(gas(), caller(), 0x1c, 0x04, 0x00, 0x20)
+                    )
+                ) {
+                    mstore(0x00, 0x8f36fa09) // `CannotLink()`.
+                    revert(0x1c, 0x04)
+                }
+            }
             _return(1);
         }
 
@@ -343,6 +359,7 @@ contract DN404NonFungibleShadow {
     receive() external payable virtual {}
 
     function _getDN404NFTStorage() internal pure returns (DN404NFTStorage storage $) {
+        /// @solidity memory-safe-assembly
         assembly {
             // keccak256(abi.encode(uint256(keccak256("dn404.nft")) - 1)) & ~bytes32(uint256(0xff))
             $.slot := 0xe8cb618a1de8ad2a6a7b358523c369cb09f40cc15da64205134c7e55c6a86700