summaryrefslogtreecommitdiff
path: root/src/inotify.c
blob: 72ba6f6869c26aa27ccb3aa396f35f84e4024a89 (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
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
/*
 *
 *  Connection Manager
 *
 *  Copyright (C) 2007-2012  Intel Corporation. All rights reserved.
 *  Copyright (C) 2012-2013  BMW Car IT GmbH. All rights reserved.
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License version 2 as
 *  published by the Free Software Foundation.
 *
 *  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 St, Fifth Floor, Boston, MA  02110-1301  USA
 *
 */

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

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

#include <connman/storage.h>

#include "connman.h"

struct connman_inotify {
	GIOChannel *channel;
	uint watch;
	int wd;

	GSList *list;
};

static GHashTable *inotify_hash;

static gboolean inotify_data(GIOChannel *channel, GIOCondition cond,
							gpointer user_data)
{
	struct connman_inotify *inotify = user_data;
	char buffer[256];
	char *next_event;
	gsize bytes_read;
	GIOStatus status;
	GSList *list;

	if (cond & (G_IO_NVAL | G_IO_ERR | G_IO_HUP)) {
		inotify->watch = 0;
		return FALSE;
	}

	status = g_io_channel_read_chars(channel, buffer,
					sizeof(buffer) -1, &bytes_read, NULL);

	switch (status) {
	case G_IO_STATUS_NORMAL:
		break;
	case G_IO_STATUS_AGAIN:
		return TRUE;
	default:
		connman_error("Reading from inotify channel failed");
		inotify->watch = 0;
		return FALSE;
	}

	next_event = buffer;

	while (bytes_read > 0) {
		struct inotify_event *event;
		gchar *ident;
		gsize len;

		event = (struct inotify_event *) next_event;
		if (event->len)
			ident = next_event + sizeof(struct inotify_event);
		else
			ident = NULL;

		len = sizeof(struct inotify_event) + event->len;

		/* check if inotify_event block fit */
		if (len > bytes_read)
			break;

		next_event += len;
		bytes_read -= len;

		for (list = inotify->list; list; list = list->next) {
			inotify_event_cb callback = list->data;

			(*callback)(event, ident);
		}
	}

	return TRUE;
}

static int create_watch(const char *path, struct connman_inotify *inotify)
{
	int fd;

	DBG("Add directory watch for %s", path);

	fd = inotify_init();
	if (fd < 0)
		return -EIO;

	inotify->wd = inotify_add_watch(fd, path,
					IN_MODIFY | IN_CREATE | IN_DELETE |
					IN_MOVED_TO | IN_MOVED_FROM);
	if (inotify->wd < 0) {
		connman_error("Creation of %s watch failed", path);
		close(fd);
		return -EIO;
	}

	inotify->channel = g_io_channel_unix_new(fd);
	if (!inotify->channel) {
		connman_error("Creation of inotify channel failed");
		inotify_rm_watch(fd, inotify->wd);
		inotify->wd = 0;

		close(fd);
		return -EIO;
	}

	g_io_channel_set_close_on_unref(inotify->channel, TRUE);
	g_io_channel_set_encoding(inotify->channel, NULL, NULL);
	g_io_channel_set_buffered(inotify->channel, FALSE);

	inotify->watch = g_io_add_watch(inotify->channel,
				G_IO_IN | G_IO_HUP | G_IO_NVAL | G_IO_ERR,
				inotify_data, inotify);

	return 0;
}

static void remove_watch(struct connman_inotify *inotify)
{
	int fd;

	if (!inotify->channel)
		return;

	if (inotify->watch > 0)
		g_source_remove(inotify->watch);

	fd = g_io_channel_unix_get_fd(inotify->channel);

	if (inotify->wd >= 0)
		inotify_rm_watch(fd, inotify->wd);

	g_io_channel_unref(inotify->channel);
}

int connman_inotify_register(const char *path, inotify_event_cb callback)
{
	struct connman_inotify *inotify;
	int err;

	if (!callback)
		return -EINVAL;

	inotify = g_hash_table_lookup(inotify_hash, path);
	if (inotify)
		goto update;

	inotify = g_try_new0(struct connman_inotify, 1);
	if (!inotify)
		return -ENOMEM;

	inotify->wd = -1;

	err = create_watch(path, inotify);
	if (err < 0) {
		g_free(inotify);
		return err;
	}

	g_hash_table_replace(inotify_hash, g_strdup(path), inotify);

update:
	inotify->list = g_slist_prepend(inotify->list, callback);

	return 0;
}

static void cleanup_inotify(gpointer user_data)
{
	struct connman_inotify *inotify = user_data;

	g_slist_free(inotify->list);

	remove_watch(inotify);
	g_free(inotify);
}

void connman_inotify_unregister(const char *path, inotify_event_cb callback)
{
	struct connman_inotify *inotify;

	inotify = g_hash_table_lookup(inotify_hash, path);
	if (!inotify)
		return;

	inotify->list = g_slist_remove(inotify->list, callback);
	if (inotify->list)
		return;

	g_hash_table_remove(inotify_hash, path);
}

int __connman_inotify_init(void)
{
	DBG("");

	inotify_hash = g_hash_table_new_full(g_str_hash, g_str_equal,
						g_free, cleanup_inotify);
	return 0;
}

void __connman_inotify_cleanup(void)
{
	DBG("");

	g_hash_table_destroy(inotify_hash);
}