summaryrefslogtreecommitdiffstats
path: root/polyp/mainloop-signal.c
blob: d7ee5010e05ff6302981f82cb2f30c56cb188b85 (plain)
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
/* $Id$ */

/***
  This file is part of polypaudio.
 
  polypaudio is free software; you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published
  by the Free Software Foundation; either version 2 of the License,
  or (at your option) any later version.
 
  polypaudio is distributed in the hope that it will be useful, but
  WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  General Public License for more details.
 
  You should have received a copy of the GNU General Public License
  along with polypaudio; if not, write to the Free Software
  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  USA.
***/

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <stdio.h>
#include <assert.h>
#include <signal.h>
#include <errno.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include "mainloop-signal.h"
#include "util.h"
#include "xmalloc.h"
#include "log.h"

struct pa_signal_event {
    int sig;
    struct sigaction saved_sigaction;
    void (*callback) (struct pa_mainloop_api*a, struct pa_signal_event *e, int signal, void *userdata);
    void *userdata;
    void (*destroy_callback) (struct pa_mainloop_api*a, struct pa_signal_event*e, void *userdata);
    struct pa_signal_event *previous, *next;
};

static struct pa_mainloop_api *api = NULL;
static int signal_pipe[2] = { -1, -1 };
static struct pa_io_event* io_event = NULL;
static struct pa_signal_event *signals = NULL;

static void signal_handler(int sig) {
    write(signal_pipe[1], &sig, sizeof(sig));
}

static void callback(struct pa_mainloop_api*a, struct pa_io_event*e, int fd, enum pa_io_event_flags f, void *userdata) {
    ssize_t r;
    int sig;
    struct pa_signal_event*s;
    assert(a && e && f == PA_IO_EVENT_INPUT && e == io_event && fd == signal_pipe[0]);

        
    if ((r = read(signal_pipe[0], &sig, sizeof(sig))) < 0) {
        if (errno == EAGAIN)
            return;

        pa_log(__FILE__": read(): %s\n", strerror(errno));
        return;
    }
    
    if (r != sizeof(sig)) {
        pa_log(__FILE__": short read()\n");
        return;
    }
    
    for (s = signals; s; s = s->next) 
        if (s->sig == sig) {
            assert(s->callback);
            s->callback(a, s, sig, s->userdata);
            break;
        }
}

int pa_signal_init(struct pa_mainloop_api *a) {
    assert(!api && a && signal_pipe[0] == -1 && signal_pipe[1] == -1 && !io_event);
    
    if (pipe(signal_pipe) < 0) {
        pa_log(__FILE__": pipe() failed: %s\n", strerror(errno));
        return -1;
    }

    pa_make_nonblock_fd(signal_pipe[0]);
    pa_make_nonblock_fd(signal_pipe[1]);
    pa_fd_set_cloexec(signal_pipe[0], 1);
    pa_fd_set_cloexec(signal_pipe[1], 1);

    api = a;
    io_event = api->io_new(api, signal_pipe[0], PA_IO_EVENT_INPUT, callback, NULL);
    assert(io_event);
    return 0;
}

void pa_signal_done(void) {
    assert(api && signal_pipe[0] >= 0 && signal_pipe[1] >= 0 && io_event);

    while (signals)
        pa_signal_free(signals);


        api->io_free(io_event);
    io_event = NULL;

    close(signal_pipe[0]);
    close(signal_pipe[1]);
    signal_pipe[0] = signal_pipe[1] = -1;

    api = NULL;
}

struct pa_signal_event* pa_signal_new(int sig, void (*callback) (struct pa_mainloop_api *api, struct pa_signal_event*e, int sig, void *userdata), void *userdata) {
    struct pa_signal_event *e = NULL;
    struct sigaction sa;
    assert(sig > 0 && callback);
    
    for (e = signals; e; e = e->next)
        if (e->sig == sig)
            goto fail;
    
    e = pa_xmalloc(sizeof(struct pa_signal_event));
    e->sig = sig;
    e->callback = callback;
    e->userdata = userdata;
    e->destroy_callback = NULL;

    memset(&sa, 0, sizeof(sa));
    sa.sa_handler = signal_handler;
    sigemptyset(&sa.sa_mask);
    sa.sa_flags = SA_RESTART;
    
    if (sigaction(sig, &sa, &e->saved_sigaction) < 0)
        goto fail;

    e->previous = NULL;
    e->next = signals;
    signals = e;

    return e;
fail:
    if (e)
        pa_xfree(e);
    return NULL;
}

void pa_signal_free(struct pa_signal_event *e) {
    assert(e);

    if (e->next)
        e->next->previous = e->previous;
    if (e->previous)
        e->previous->next = e->next;
    else
        signals = e->next;

    sigaction(e->sig, &e->saved_sigaction, NULL);

    if (e->destroy_callback)
        e->destroy_callback(api, e, e->userdata);
    
    pa_xfree(e);
}

void pa_signal_set_destroy(struct pa_signal_event *e, void (*callback) (struct pa_mainloop_api *api, struct pa_signal_event*e, void *userdata)) {
    assert(e);
    e->destroy_callback = callback;
}