diff --git a/lib/isc/include/isc/ondestroy.h b/lib/isc/include/isc/ondestroy.h new file mode 100644 index 0000000000..1709f5cf48 --- /dev/null +++ b/lib/isc/include/isc/ondestroy.h @@ -0,0 +1,106 @@ +/* + * Copyright (C) 2000 Internet Software Consortium. + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS + * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE + * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL + * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR + * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS + * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS + * SOFTWARE. + */ + +#ifndef ISC_ONDESTROY_H +#define ISC_ONDESTROY_H 1 + +#include + +#include + +ISC_LANG_BEGINDECLS + +/* + * ondestroy handling. + * + * Any class ``X'' of objects that wants to send out notifications + * on its destruction should declare a field of type isc_ondestroy_t + * (call it 'ondest'). + * + * typedef struct { + * ... + * isc_ondestroy_t ondest; + * ... + * } X; + * + * When an object ``A'' of type X is created + * it must initialize the field ondest with a call to + * + * isc_ondestroy_init(&A->ondest). + * + * X should also provide a registration function for third-party + * objects to call to register their interest in being told about + * the destruction of a particular instance of X. + * + * isc_result_t + * X_ondestroy(X *instance, isc_task_t *task, + * isc_event_t **eventp) { + * return(isc_ondestroy_register(&instance->ondest, task,eventp)); + * } + * + * Note: locking of the ondestory structure embedded inside of X, is + * X's responsibility. + * + * When an instance of X is destroyed, a call to isc_ondestroy_notify() + * sends the notifications: + * + * X *instance; + * isc_ondestroy_t ondest = instance->ondest; + * + * ... completely cleanup 'instance' here... + * + * isc_ondestroy_notify(&ondest, instance); + * + * + * see dns/zone.c for an ifdef'd-out example. + */ + +typedef struct { + unsigned int magic; + isc_eventlist_t events; +} isc_ondestroy_t; + +void isc_ondestroy_init(isc_ondestroy_t *ondest); +/* + * Initialize the on ondest structure. *must* be called before first call + * to isc_ondestroy_register(). + */ + +isc_result_t isc_ondestroy_register(isc_ondestroy_t *ondest, + isc_task_t *task, + isc_event_t **eventp); + +/* + * Stores task and *eventp away inside *ondest. Ownership of **event is + * taken from the caller (and *eventp is set to NULL). The task is attached + * to. + */ + + +void isc_ondestroy_notify(isc_ondestroy_t *ondest, void *sender); +/* + * Dispatches the event(s) to the task(s) that were given in + * isc_ondestroy_register call(s) (done via calls to + * isc_task_sendanddetach()). Before dispatch, the sender value of each + * event structure is set to the value of the sender paramater. The + * internal structures of the ondest parameter are cleaned out, so no other + * cleanup is needed. + */ + +ISC_LANG_ENDDECLS + +#endif /* ISC_ONDESTROY_H */ diff --git a/lib/isc/ondestroy.c b/lib/isc/ondestroy.c new file mode 100644 index 0000000000..fd8afae55b --- /dev/null +++ b/lib/isc/ondestroy.c @@ -0,0 +1,83 @@ +/* + * Copyright (C) 2000 Internet Software Consortium. + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS + * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE + * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL + * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR + * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS + * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS + * SOFTWARE. + */ + +#include + +#include +#include +#include +#include + +#define ONDESTROY_MAGIC 0x44655374 /* DeSt */ +#define VALID_ONDESTROY(s) (s != NULL && (s->magic == ONDESTROY_MAGIC)) + +void +isc_ondestroy_init(isc_ondestroy_t *ondest) +{ + ondest->magic = ONDESTROY_MAGIC; + ISC_LIST_INIT(ondest->events); +} + + +isc_result_t +isc_ondestroy_register(isc_ondestroy_t *ondest, + isc_task_t *task, isc_event_t **eventp) +{ + isc_event_t *theevent; + isc_task_t *thetask = NULL; + + REQUIRE(VALID_ONDESTROY(ondest)); + REQUIRE(task != NULL); + REQUIRE(eventp != NULL); + + theevent = *eventp; + + REQUIRE(theevent != NULL); + + isc_task_attach(task, &thetask); + + theevent->sender = thetask; + + ISC_LIST_APPEND(ondest->events, theevent, link); + + return (ISC_R_SUCCESS); +} + + + +void +isc_ondestroy_notify(isc_ondestroy_t *ondest, void *sender) +{ + isc_event_t *eventp; + isc_task_t *task; + + REQUIRE(VALID_ONDESTROY(ondest)); + + eventp = ISC_LIST_HEAD(ondest->events); + while (eventp != NULL) { + ISC_LIST_UNLINK(ondest->events, eventp, link); + + task = eventp->sender; + eventp->sender = sender; + + isc_task_sendanddetach(&task, &eventp); + + eventp = ISC_LIST_HEAD(ondest->events); + } +} + +