queue: implement queue handles for Windows

Author: compnerd

src/queue.c

@@ -4611,6 +4611,10 @@ _dispatch_runloop_queue_class_poke(dispatch_queue_t dq)
 		result = eventfd_write(handle, 1);
 	} while (result == -1 && errno == EINTR);
 	(void)dispatch_assume_zero(result);
+#elif defined(_WIN32)
+	BOOL bSuccess;
+	bSuccess = SetEvent(handle);
+	(void)dispatch_assume(bSuccess);
 #else
 #error "runloop support not implemented on this platform"
 #endif
@@ -6312,7 +6316,12 @@ _dispatch_runloop_queue_handle_init(void *ctxt)
 	}
 	handle = fd;
 #elif defined(_WIN32)
-	handle = INVALID_HANDLE_VALUE;
+	HANDLE hEvent = CreateEventW(NULL, /*bManualReset=*/TRUE,
+		/*bInitialState=*/FALSE, NULL);
+	if (hEvent == NULL) {
+		DISPATCH_INTERNAL_CRASH(GetLastError(), "CreateEventW");
+	}
+	handle = hEvent;
 #else
 #error "runloop support not implemented on this platform"
 #endif