aboutsummaryrefslogtreecommitdiff
path: root/src/InotifySource.cxx
blob: 5552ed5784dd339edc9f90e8b387ce4b34f5eda3 (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
/*
 * Copyright (C) 2003-2013 The Music Player Daemon Project
 * http://www.musicpd.org
 *
 * This program 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.
 *
 * This program 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 this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

#include "config.h"
#include "InotifySource.hxx"
#include "util/fifo_buffer.h"
#include "fd_util.h"
#include "mpd_error.h"

#include <glib.h>

#include <sys/inotify.h>
#include <unistd.h>
#include <errno.h>

#undef G_LOG_DOMAIN
#define G_LOG_DOMAIN "inotify"

/**
 * A GQuark for GError instances.
 */
static inline GQuark
mpd_inotify_quark(void)
{
	return g_quark_from_static_string("inotify");
}

bool
InotifySource::OnSocketReady(gcc_unused unsigned flags)
{
	void *dest;
	size_t length;
	ssize_t nbytes;

	dest = fifo_buffer_write(buffer, &length);
	if (dest == NULL)
		MPD_ERROR("buffer full");

	nbytes = read(Get(), dest, length);
	if (nbytes < 0)
		MPD_ERROR("failed to read from inotify: %s",
			  g_strerror(errno));
	if (nbytes == 0)
		MPD_ERROR("end of file from inotify");

	fifo_buffer_append(buffer, nbytes);

	while (true) {
		const char *name;

		const struct inotify_event *event =
			(const struct inotify_event *)
			fifo_buffer_read(buffer, &length);
		if (event == NULL || length < sizeof(*event) ||
		    length < sizeof(*event) + event->len)
			break;

		if (event->len > 0 && event->name[event->len - 1] == 0)
			name = event->name;
		else
			name = NULL;

		callback(event->wd, event->mask, name, callback_ctx);
		fifo_buffer_consume(buffer, sizeof(*event) + event->len);
	}

	return true;
}

inline
InotifySource::InotifySource(EventLoop &_loop,
			     mpd_inotify_callback_t _callback, void *_ctx,
			     int _fd)
	:SocketMonitor(_fd, _loop),
	 callback(_callback), callback_ctx(_ctx),
	 buffer(fifo_buffer_new(4096))
{
	ScheduleRead();

}

InotifySource *
InotifySource::Create(EventLoop &loop,
		      mpd_inotify_callback_t callback, void *callback_ctx,
		      GError **error_r)
{
	int fd = inotify_init_cloexec();
	if (fd < 0) {
		g_set_error(error_r, mpd_inotify_quark(), errno,
			    "inotify_init() has failed: %s",
			    g_strerror(errno));
		return NULL;
	}

	return new InotifySource(loop, callback, callback_ctx, fd);
}

InotifySource::~InotifySource()
{
	fifo_buffer_free(buffer);
}

int
InotifySource::Add(const char *path_fs, unsigned mask, GError **error_r)
{
	int wd = inotify_add_watch(Get(), path_fs, mask);
	if (wd < 0)
		g_set_error(error_r, mpd_inotify_quark(), errno,
			    "inotify_add_watch() has failed: %s",
			    g_strerror(errno));

	return wd;
}

void
InotifySource::Remove(unsigned wd)
{
	int ret = inotify_rm_watch(Get(), wd);
	if (ret < 0 && errno != EINVAL)
		g_warning("inotify_rm_watch() has failed: %s",
			  g_strerror(errno));

	/* EINVAL may happen here when the file has been deleted; the
	   kernel seems to auto-unregister deleted files */
}