Fixes krakjoe#733: accept recognizes socket blocking state

src/socket.c

@@ -300,15 +300,21 @@ void pthreads_socket_accept(zval *object, zend_class_entry *ce, zval *return_val
 			ZSTR_VAL(ce->name));
 		return;
 	}
+	php_socket_t acceptedFd = accept(threaded->store.sock->fd, (struct sockaddr*) &sa, &sa_len);
 
+	if(acceptedFd < 0) {
+		if(threaded->store.sock->blocking) {
+			zend_throw_exception_ex(spl_ce_RuntimeException, 0,
+			    "socket found in invalid state");
+		}
+		ZVAL_NULL(return_value);
+		return;
+	}
 	object_init_ex(return_value, ce);
 
 	accepted = PTHREADS_FETCH_FROM(Z_OBJ_P(return_value));
-	accepted->store.sock->fd = 
-		accept(threaded->store.sock->fd, (struct sockaddr*) &sa, &sa_len);
-
-	PTHREADS_SOCKET_CHECK(accepted->store.sock);
-
+	accepted->store.sock->fd = acceptedFd;
+	accepted->store.sock->blocking = 1;
 	accepted->store.sock->domain = ((struct sockaddr*) &sa)->sa_family;
 }