std: add windows.closesocket

Author: daurnimator

lib/std/os/windows.zig

@@ -684,6 +684,16 @@ pub fn WSASocketW(
     return rc;
 }
 
+pub fn closesocket(s: ws2_32.SOCKET) !void {
+    switch(ws2_32.closesocket(s)) {
+        0 => {},
+        ws2_32.SOCKET_ERROR => switch (ws2_32.WSAGetLastError()) {
+            else => |err| return unexpectedWSAError(err),
+        },
+        else => unreachable,
+    }
+}
+
 pub fn WSAIoctl(
     s: ws2_32.SOCKET,
     dwIoControlCode: DWORD,

lib/std/os/windows/ws2_32.zig

@@ -244,6 +244,7 @@ pub extern "ws2_32" stdcallcc fn WSASocketW(
     g: GROUP,
     dwFlags: DWORD,
 ) SOCKET;
+pub extern "ws2_32" stdcallcc fn closesocket(s: SOCKET) c_int;
 pub extern "ws2_32" stdcallcc fn WSAIoctl(
     s: SOCKET,
     dwIoControlCode: DWORD,