* Called when the process forked. It mostly does the same as the * knote(), activating all knotes registered to be activated when the * process forked. Additionally, for each knote attached to the * parent, check whether user wants to track the new process. If so * attach a new knote to it, and immediately report an event with the * child's pid. */
| 527 | * child's pid. |
| 528 | */ |
| 529 | void |
| 530 | knote_fork(struct knlist *list, int pid) |
| 531 | { |
| 532 | struct kqueue *kq; |
| 533 | struct knote *kn; |
| 534 | struct kevent kev; |
| 535 | int error; |
| 536 | |
| 537 | MPASS(list != NULL); |
| 538 | KNL_ASSERT_LOCKED(list); |
| 539 | if (SLIST_EMPTY(&list->kl_list)) |
| 540 | return; |
| 541 | |
| 542 | memset(&kev, 0, sizeof(kev)); |
| 543 | SLIST_FOREACH(kn, &list->kl_list, kn_selnext) { |
| 544 | kq = kn->kn_kq; |
| 545 | KQ_LOCK(kq); |
| 546 | if (kn_in_flux(kn) && (kn->kn_status & KN_SCAN) == 0) { |
| 547 | KQ_UNLOCK(kq); |
| 548 | continue; |
| 549 | } |
| 550 | |
| 551 | /* |
| 552 | * The same as knote(), activate the event. |
| 553 | */ |
| 554 | if ((kn->kn_sfflags & NOTE_TRACK) == 0) { |
| 555 | if (kn->kn_fop->f_event(kn, NOTE_FORK)) |
| 556 | KNOTE_ACTIVATE(kn, 1); |
| 557 | KQ_UNLOCK(kq); |
| 558 | continue; |
| 559 | } |
| 560 | |
| 561 | /* |
| 562 | * The NOTE_TRACK case. In addition to the activation |
| 563 | * of the event, we need to register new events to |
| 564 | * track the child. Drop the locks in preparation for |
| 565 | * the call to kqueue_register(). |
| 566 | */ |
| 567 | kn_enter_flux(kn); |
| 568 | KQ_UNLOCK(kq); |
| 569 | list->kl_unlock(list->kl_lockarg); |
| 570 | |
| 571 | /* |
| 572 | * Activate existing knote and register tracking knotes with |
| 573 | * new process. |
| 574 | * |
| 575 | * First register a knote to get just the child notice. This |
| 576 | * must be a separate note from a potential NOTE_EXIT |
| 577 | * notification since both NOTE_CHILD and NOTE_EXIT are defined |
| 578 | * to use the data field (in conflicting ways). |
| 579 | */ |
| 580 | kev.ident = pid; |
| 581 | kev.filter = kn->kn_filter; |
| 582 | kev.flags = kn->kn_flags | EV_ADD | EV_ENABLE | EV_ONESHOT | |
| 583 | EV_FLAG2; |
| 584 | kev.fflags = kn->kn_sfflags; |
| 585 | kev.data = kn->kn_id; /* parent */ |
| 586 | kev.udata = kn->kn_kevent.udata;/* preserve udata */ |
no test coverage detected