mirror of
https://github.com/libevent/libevent.git
synced 2025-01-09 00:56:20 +08:00
720bd933c8
When using the signal.c signal backend, Libevent currently only allows one event_base to actually receive signals at a time. (This has been the behavior since at least 1.4 and probably much earlier.) Now, we detect and warn if you're likely to be racing about which signal goes to which thread. We also add a lock to control modifications of the evsig_base field, to avoid race conditions like those found by Jason Toffaletti. Also, more comments. Comments are good.
69 lines
2.6 KiB
C
69 lines
2.6 KiB
C
/*
|
|
* Copyright 2000-2007 Niels Provos <provos@citi.umich.edu>
|
|
* Copyright 2007-2010 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 _EVSIGNAL_H_
|
|
#define _EVSIGNAL_H_
|
|
|
|
#ifndef evutil_socket_t
|
|
#include "event2/util.h"
|
|
#endif
|
|
#include <signal.h>
|
|
|
|
typedef void (*ev_sighandler_t)(int);
|
|
|
|
/* Data structure for the default signal-handling implementation in signal.c
|
|
*/
|
|
struct evsig_info {
|
|
/* Event watching ev_signal_pair[1] */
|
|
struct event ev_signal;
|
|
/* Socketpair used to send notifications from the signal handler */
|
|
evutil_socket_t ev_signal_pair[2];
|
|
/* True iff we've added the ev_signal event yet. */
|
|
int ev_signal_added;
|
|
/* Count of the number of signals we're currently watching. */
|
|
int ev_n_signals_added;
|
|
|
|
volatile sig_atomic_t evsig_caught;
|
|
sig_atomic_t evsigcaught[NSIG];
|
|
|
|
/* Array of previous signal handler objects before Libevent started
|
|
* messing with them. Used to restore old signal handlers. */
|
|
#ifdef _EVENT_HAVE_SIGACTION
|
|
struct sigaction **sh_old;
|
|
#else
|
|
ev_sighandler_t **sh_old;
|
|
#endif
|
|
/* Size of sh_old. */
|
|
int sh_old_max;
|
|
};
|
|
int evsig_init(struct event_base *);
|
|
void evsig_process(struct event_base *);
|
|
void evsig_dealloc(struct event_base *);
|
|
|
|
void evsig_set_base(struct event_base *base);
|
|
|
|
#endif /* _EVSIGNAL_H_ */
|