eth-interface

commit b895ebbef9bebe2de8833ecc87894b806c312d80
parent c6493162b2484ff95f203bd5fb245baab4cd7110
Author: lash <dev@holbrook.no>
Date:   Sat, 25 Mar 2023 05:46:30 +0000

Add interface check sample contract

Diffstat:
A
solidity/Interface.sol
 | 
36
++++++++++++++++++++++++++++++++++++

1 file changed, 36 insertions(+), 0 deletions(-)
diff --git a/solidity/Interface.sol b/solidity/Interface.sol
@@ -0,0 +1,36 @@
+pragma solidity >= 0.8.0;
+
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+contract InterfaceCheckSample {
+	uint256 interfaces;
+
+	constructor(uint256 _interfaces) {
+		interfaces = _interfaces;	
+	}
+
+	// EIP-165
+	function supportsInterface(bytes4 interfaceID) external view returns (bool) {
+		uint32 interfaceN;
+		uint32 masked;
+
+		interfaceN = uint32(interfaceID);
+
+		// EIP165 interface id
+		if (uint32(interfaceID) ==  0x01ffc9a7) {
+			return true;
+		}
+
+		for (uint256 i = 0; i < 256; i += 32) {
+			masked = uint32((interfaces >> i) & 0xffffffff);
+			if (masked == 0) {
+				return false;
+			}
+			if (interfaceN == masked) {
+				return true;
+			}
+		}
+
+		return false;
+	}
+}