libinetutil.h revision 7c478bd95313f5f23a4c958a745db2134aa03244
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License, Version 1.0 only
* (the "License"). You may not use this file except in compliance
* with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2004 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#ifndef _LIBINETUTIL_H
#define _LIBINETUTIL_H
#pragma ident "%Z%%M% %I% %E% SMI"
/*
* Contains SMI-private API for general internet functionality
*/
#ifdef __cplusplus
extern "C" {
#endif
#include <netinet/inetutil.h>
typedef struct {
int ifsp_modcnt; /* Number of modules to be pushed */
} ifspec_t;
/*
* Timer queues
*
* timer queues are a facility for managing timeouts in unix. in the
* event driven model, unix provides us with poll(2)/select(3C), which
* allow us to coordinate waiting on multiple descriptors with an
* optional timeout. however, often (as is the case with the DHCP
* agent), we want to manage multiple independent timeouts (say, one
* for waiting for an OFFER to come back from a server in response to
* a DISCOVER sent out on one interface, and another for waiting for
* the T1 time on another interface). timer queues allow us to do
* this in the event-driven model.
*
* note that timer queues do not in and of themselves provide the
* event driven model (for instance, there is no handle_events()
* routine). they merely provide the hooks to support multiple
* independent timeouts. this is done for both simplicity and
* applicability (for instance, while one approach would be to use
* this timer queue with poll(2), another one would be to use SIGALRM
* to wake up periodically, and then process all the expired timers.)
*/
typedef struct iu_timer_queue iu_tq_t;
/*
* a iu_timer_id_t refers to a given timer. its value should not be
* interpreted by the interface consumer. it is a signed arithmetic
* type, and no valid iu_timer_id_t has the value `-1'.
*/
typedef int iu_timer_id_t;
/*
* a iu_tq_callback_t is a function that is called back in response to a
* timer expiring. it may then carry out any necessary work,
* including rescheduling itself for callback or scheduling /
* cancelling other timers. the `void *' argument is the same value
* that was passed into iu_schedule_timer(), and if it is dynamically
* allocated, it is the callback's responsibility to know that, and to
* free it.
*/
typedef void iu_tq_callback_t(iu_tq_t *, void *);
iu_tq_t *iu_tq_create(void);
void iu_tq_destroy(iu_tq_t *);
void *);
void *);
int iu_expire_timers(iu_tq_t *);
int iu_earliest_timer(iu_tq_t *);
/*
* Event Handler
*
* an event handler is an object-oriented "wrapper" for select(3C) /
* poll(2), aimed to make the event demultiplexing system calls easier
* to use and provide a generic reusable component. instead of
* applications directly using select(3C) / poll(2), they register
* events that should be received with the event handler, providing a
* callback function to call when the event occurs. they then call
* iu_handle_events() to wait and callback the registered functions
* when events occur. also called a `reactor'.
*/
typedef struct iu_event_handler iu_eh_t;
/*
* an iu_event_id_t refers to a given event. its value should not be
* interpreted by the interface consumer. it is a signed arithmetic
* type, and no valid iu_event_id_t has the value `-1'.
*/
typedef int iu_event_id_t;
/*
* an iu_eh_callback_t is a function that is called back in response to
* an event occurring. it may then carry out any work necessary in
* response to the event. it receives the file descriptor upon which
* the event occurred, a bit array of events that occurred (the same
* array used as the revents by poll(2)), and its context through the
* `void *' that was originally passed into iu_register_event().
*
* NOTE: the same descriptor may not be registered multiple times for
* different callbacks. if this behavior is desired, either use dup(2)
* to get a unique descriptor, or demultiplex in the callback function
* based on the events.
*/
typedef void iu_eh_sighandler_t(iu_eh_t *, int, void *);
iu_eh_t *iu_eh_create(void);
void iu_eh_destroy(iu_eh_t *);
void *);
void iu_stop_handling_events(iu_eh_t *, unsigned int,
iu_eh_shutdown_t *, void *);
void *);
int iu_eh_unregister_signal(iu_eh_t *, int, void **);
#endif /* !defined(_KERNEL) && !defined(_BOOT) */
#ifdef __cplusplus
}
#endif
#endif /* !_LIBINETUTIL_H */