/* $NetBSD: defer-internal.h,v 1.1.1.1 2013/04/11 16:43:21 christos Exp $ */ /* * Copyright (c) 2009-2012 Niels Provos and Nick Mathewson * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. The name of the author may not be used to endorse or promote products * derived from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ #ifndef _DEFER_INTERNAL_H_ #define _DEFER_INTERNAL_H_ #ifdef __cplusplus extern "C" { #endif #include "event2/event-config.h" #include struct deferred_cb; typedef void (*deferred_cb_fn)(struct deferred_cb *, void *); /** A deferred_cb is a callback that can be scheduled to run as part of * an event_base's event_loop, rather than running immediately. */ struct deferred_cb { /** Links to the adjacent active (pending) deferred_cb objects. */ TAILQ_ENTRY (deferred_cb) cb_next; /** True iff this deferred_cb is pending in an event_base. */ unsigned queued : 1; /** The function to execute when the callback runs. */ deferred_cb_fn cb; /** The function's second argument. */ void *arg; }; /** A deferred_cb_queue is a list of deferred_cb that we can add to and run. */ struct deferred_cb_queue { /** Lock used to protect the queue. */ void *lock; /** How many entries are in the queue? */ int active_count; /** Function called when adding to the queue from another thread. */ void (*notify_fn)(struct deferred_cb_queue *, void *); void *notify_arg; /** Deferred callback management: a list of deferred callbacks to * run active the active events. */ TAILQ_HEAD (deferred_cb_list, deferred_cb) deferred_cb_list; }; /** Initialize an empty, non-pending deferred_cb. @param deferred The deferred_cb structure to initialize. @param cb The function to run when the deferred_cb executes. @param arg The function's second argument. */ void event_deferred_cb_init(struct deferred_cb *, deferred_cb_fn, void *); /** Cancel a deferred_cb if it is currently scheduled in an event_base. */ void event_deferred_cb_cancel(struct deferred_cb_queue *, struct deferred_cb *); /** Activate a deferred_cb if it is not currently scheduled in an event_base. */ void event_deferred_cb_schedule(struct deferred_cb_queue *, struct deferred_cb *); #define LOCK_DEFERRED_QUEUE(q) \ EVLOCK_LOCK((q)->lock, 0) #define UNLOCK_DEFERRED_QUEUE(q) \ EVLOCK_UNLOCK((q)->lock, 0) #ifdef __cplusplus } #endif void event_deferred_cb_queue_init(struct deferred_cb_queue *); struct deferred_cb_queue *event_base_get_deferred_cb_queue(struct event_base *); #endif /* _EVENT_INTERNAL_H_ */