aboutsummaryrefslogtreecommitdiffstats
path: root/src/InotifySource.cxx
blob: c6f0ae4db79c71474bd2781d8f2ed220044d72e5 (plain) (blame)
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
/*
 * 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 "util/Error.hxx"
#include "system/fd_util.h"
#include "system/FatalError.hxx"

#include <glib.h>

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

#undef G_LOG_DOMAIN
#define G_LOG_DOMAIN "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)
		FatalError("buffer full");

	nbytes = read(Get(), dest, length);
	if (nbytes < 0)
		FatalSystemError("Failed to read from inotify");
	if (nbytes == 0)
		FatalError("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,
		      Error &error)
{
	int fd = inotify_init_cloexec();
	if (fd < 0) {
		error.SetErrno("inotify_init() has failed");
		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, Error &error)
{
	int wd = inotify_add_watch(Get(), path_fs, mask);
	if (wd < 0)
		error.SetErrno("inotify_add_watch() has failed");

	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 */
}