1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
|
/* $OpenBSD: signal.c,v 1.12 2008/05/02 06:09:11 brad Exp $ */
/*
* Copyright 2000-2002 Niels Provos <provos@citi.umich.edu>
* All rights reserved.
*
* 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.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <sys/types.h>
#include <sys/tree.h>
#ifdef HAVE_SYS_TIME_H
#include <sys/time.h>
#else
#include <sys/_time.h>
#endif
#include <sys/queue.h>
#include <sys/socket.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>
#ifdef HAVE_FCNTL_H
#include <fcntl.h>
#endif
#include <assert.h>
#include "event.h"
#include "event-internal.h"
#include "evsignal.h"
#include "log.h"
struct event_base *evsignal_base = NULL;
static void evsignal_handler(int sig);
/* Callback for when the signal handler write a byte to our signaling socket */
static void
evsignal_cb(int fd, short what, void *arg)
{
static char signals[100];
struct event *ev = arg;
ssize_t n;
n = read(fd, signals, sizeof(signals));
if (n == -1)
event_err(1, "%s: read", __func__);
event_add(ev, NULL);
}
#ifdef HAVE_SETFD
#define FD_CLOSEONEXEC(x) do { \
if (fcntl(x, F_SETFD, 1) == -1) \
event_warn("fcntl(%d, F_SETFD)", x); \
} while (0)
#else
#define FD_CLOSEONEXEC(x)
#endif
void
evsignal_init(struct event_base *base)
{
/*
* Our signal handler is going to write to one end of the socket
* pair to wake up our event loop. The event loop then scans for
* signals that got delivered.
*/
if (socketpair(AF_UNIX, SOCK_STREAM, 0, base->sig.ev_signal_pair) == -1)
event_err(1, "%s: socketpair", __func__);
FD_CLOSEONEXEC(base->sig.ev_signal_pair[0]);
FD_CLOSEONEXEC(base->sig.ev_signal_pair[1]);
base->sig.evsignal_caught = 0;
memset(&base->sig.evsigcaught, 0, sizeof(sig_atomic_t)*NSIG);
fcntl(base->sig.ev_signal_pair[0], F_SETFL, O_NONBLOCK);
event_set(&base->sig.ev_signal, base->sig.ev_signal_pair[1], EV_READ,
evsignal_cb, &base->sig.ev_signal);
base->sig.ev_signal.ev_base = base;
base->sig.ev_signal.ev_flags |= EVLIST_INTERNAL;
}
int
evsignal_add(struct event *ev)
{
int evsignal;
struct sigaction sa;
struct event_base *base = ev->ev_base;
if (ev->ev_events & (EV_READ|EV_WRITE))
event_errx(1, "%s: EV_SIGNAL incompatible use", __func__);
evsignal = EVENT_SIGNAL(ev);
memset(&sa, 0, sizeof(sa));
sa.sa_handler = evsignal_handler;
sigfillset(&sa.sa_mask);
sa.sa_flags |= SA_RESTART;
/* catch signals if they happen quickly */
evsignal_base = base;
if (sigaction(evsignal, &sa, NULL) == -1)
return (-1);
if (!base->sig.ev_signal_added) {
base->sig.ev_signal_added = 1;
event_add(&base->sig.ev_signal, NULL);
}
return (0);
}
int
evsignal_del(struct event *ev)
{
return (sigaction(EVENT_SIGNAL(ev),(struct sigaction *)SIG_DFL, NULL));
}
static void
evsignal_handler(int sig)
{
int save_errno = errno;
if(evsignal_base == NULL) {
event_warn(
"%s: received signal %s, but have no base configured",
__func__, sig);
return;
}
evsignal_base->sig.evsigcaught[sig]++;
evsignal_base->sig.evsignal_caught = 1;
/* Wake up our notification mechanism */
write(evsignal_base->sig.ev_signal_pair[0], "a", 1);
errno = save_errno;
}
void
evsignal_process(struct event_base *base)
{
struct event *ev;
sig_atomic_t ncalls;
base->sig.evsignal_caught = 0;
TAILQ_FOREACH(ev, &base->sig.signalqueue, ev_signal_next) {
ncalls = base->sig.evsigcaught[EVENT_SIGNAL(ev)];
if (ncalls) {
if (!(ev->ev_events & EV_PERSIST))
event_del(ev);
event_active(ev, EV_SIGNAL, ncalls);
base->sig.evsigcaught[EVENT_SIGNAL(ev)] = 0;
}
}
}
void
evsignal_dealloc(struct event_base *base)
{
if(base->sig.ev_signal_added) {
event_del(&base->sig.ev_signal);
base->sig.ev_signal_added = 0;
}
assert(TAILQ_EMPTY(&base->sig.signalqueue));
close(base->sig.ev_signal_pair[0]);
base->sig.ev_signal_pair[0] = -1;
close(base->sig.ev_signal_pair[1]);
base->sig.ev_signal_pair[1] = -1;
}
|
