File: inotify-path.c

package info (click to toggle)
gnome-vfs 1:2.24.4-6.1
  • links: PTS, VCS
  • area: main
  • in suites: sid, stretch
  • size: 17,144 kB
  • ctags: 10,422
  • sloc: ansic: 78,500; sh: 10,341; makefile: 902; perl: 99
file content (378 lines) | stat: -rw-r--r-- 9,316 bytes parent folder | download | duplicates (5)
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
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
/* -*- Mode: C; indent-tabs-mode: t; c-basic-offset: 8; tab-width: 8 -*- */

/* inotify-helper.c - Gnome VFS Monitor based on inotify.

   Copyright (C) 2006 John McCutchan

   The Gnome Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Library General Public License as
   published by the Free Software Foundation; either version 2 of the
   License, or (at your option) any later version.

   The Gnome Library 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
   Library General Public License for more details.

   You should have received a copy of the GNU Library General Public
   License along with the Gnome Library; see the file COPYING.LIB.  If not,
   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
   Boston, MA 02111-1307, USA.

   Authors: 
		 John McCutchan <john@johnmccutchan.com>
*/

#include "config.h"

/* Don't put conflicting kernel types in the global namespace: */
#define __KERNEL_STRICT_NAMES

#include <sys/inotify.h>
#include <string.h>
#include <glib.h>
#include <libgnomevfs/gnome-vfs-module-shared.h>
#include <libgnomevfs/gnome-vfs-utils.h>
#include "inotify-kernel.h"
#include "inotify-path.h"
#include "inotify-missing.h"

#define IP_INOTIFY_MASK (IN_MODIFY|IN_ATTRIB|IN_MOVED_FROM|IN_MOVED_TO|IN_DELETE|IN_CREATE|IN_DELETE_SELF|IN_UNMOUNT|IN_MOVE_SELF)

typedef struct ip_watched_dir_s {
	char *path;
	/* TODO: We need to maintain a tree of watched directories
	 * so that we can deliver move/delete events to sub folders.
	 * Or the application could do it...
	 */
	struct ip_watched_dir_s *parent;
	GList *			 children;

	/* Inotify state */
	gint32 wd;

	/* List of inotify subscriptions */
	GList *subs;
} ip_watched_dir_t;

static gboolean     ip_debug_enabled = FALSE;
#define IP_W if (ip_debug_enabled) g_warning

/* path -> ip_watched_dir */
static GHashTable * path_dir_hash = NULL;
/* ih_sub_t * -> ip_watched_dir *
 *
 * Each subscription is attached to a watched directory or it is on
 * the missing list
 */
static GHashTable * sub_dir_hash = NULL;
/* This hash holds GLists of ip_watched_dir_t *'s
 * We need to hold a list because symbolic links can share
 * the same wd
 */
static GHashTable * wd_dir_hash = NULL;

static ip_watched_dir_t *	ip_watched_dir_new (const char *path, int wd);
static void 			ip_watched_dir_free (ip_watched_dir_t *dir);
static void 			ip_event_callback (ik_event_t *event);

static void (*event_callback)(ik_event_t *event, ih_sub_t *sub);

gboolean ip_startup (void (*cb)(ik_event_t *event, ih_sub_t *sub))
{
	static gboolean initialized = FALSE;
	static gboolean result = FALSE;

	if (initialized == TRUE) {
		return result;
	}

	initialized = TRUE;
	event_callback = cb;
	result = ik_startup (ip_event_callback);

	if (!result) {
		return FALSE;
	}

	path_dir_hash = g_hash_table_new(g_str_hash, g_str_equal);
	sub_dir_hash = g_hash_table_new(g_direct_hash, g_direct_equal);
	wd_dir_hash = g_hash_table_new(g_direct_hash, g_direct_equal);

	return TRUE;
}

static void
ip_map_path_dir (const char *path, ip_watched_dir_t *dir)
{
	g_assert (path && dir);
	g_hash_table_insert(path_dir_hash, dir->path, dir);
}

static void
ip_map_sub_dir (ih_sub_t *sub, ip_watched_dir_t *dir)
{
	/* Associate subscription and directory */
	g_assert (dir && sub);
	g_hash_table_insert (sub_dir_hash, sub, dir);
	dir->subs = g_list_prepend (dir->subs, sub);
}

static void
ip_map_wd_dir (gint32 wd, ip_watched_dir_t *dir)
{
	g_assert (wd >= 0 && dir);
	GList *dir_list = g_hash_table_lookup (wd_dir_hash, GINT_TO_POINTER(wd));
	dir_list = g_list_prepend (dir_list, dir);
	g_hash_table_replace(wd_dir_hash, GINT_TO_POINTER(dir->wd), dir_list);
}

gboolean ip_start_watching (ih_sub_t *sub)
{
	gint32 wd;
	int err;
	ip_watched_dir_t *dir;

	g_assert (sub);
	g_assert (!sub->cancelled);
	g_assert (sub->dirname);

	IP_W("Starting to watch %s\n", sub->dirname);
	dir = g_hash_table_lookup (path_dir_hash, sub->dirname);
	if (dir)
	{
		IP_W("Already watching\n");
		goto out;
	}
	
	IP_W("Trying to add inotify watch ");
	wd = ik_watch (sub->dirname, IP_INOTIFY_MASK|IN_ONLYDIR|sub->extra_flags, &err);
	if (wd < 0) 
	{
		IP_W("Failed\n");
		return FALSE;
	} else {
		/* Create new watched directory and associate it with the 
		 * wd hash and path hash
		 */
		IP_W("Success\n");
		dir = ip_watched_dir_new (sub->dirname, wd);
		ip_map_wd_dir (wd, dir);
		ip_map_path_dir (sub->dirname, dir);
	}

out:
	ip_map_sub_dir (sub, dir);

	return TRUE;
}

static void
ip_unmap_path_dir (const char *path, ip_watched_dir_t *dir)
{
	g_assert (path && dir);
	g_hash_table_remove (path_dir_hash, dir->path);
}

static void
ip_unmap_wd_dir (gint32 wd, ip_watched_dir_t *dir)
{
	GList *dir_list = g_hash_table_lookup (wd_dir_hash, GINT_TO_POINTER(wd));
	if (!dir_list)
		return;
	g_assert (wd >= 0 && dir);
	dir_list = g_list_remove (dir_list, dir);
	if (dir_list == NULL) {
		g_hash_table_remove (wd_dir_hash, GINT_TO_POINTER(dir->wd));
	} else {
		g_hash_table_replace (wd_dir_hash, GINT_TO_POINTER(dir->wd), dir_list);
	}
}

static void
ip_unmap_wd (gint32 wd)
{
	GList *dir_list = g_hash_table_lookup (wd_dir_hash, GINT_TO_POINTER(wd));
	if (!dir_list)
		return;
	g_assert (wd >= 0);
	g_hash_table_remove (wd_dir_hash, GINT_TO_POINTER(wd));
	g_list_free (dir_list);
}

static void
ip_unmap_sub_dir (ih_sub_t *sub, ip_watched_dir_t *dir)
{
	g_assert (sub && dir);
	g_hash_table_remove (sub_dir_hash, sub);
	dir->subs = g_list_remove (dir->subs, sub);
}

static void
ip_unmap_all_subs (ip_watched_dir_t *dir)
{
	GList *l = NULL;

	for (l = dir->subs; l; l = l->next)
	{
		ih_sub_t *sub = l->data;
		g_hash_table_remove (sub_dir_hash, sub);
	}
	g_list_free (dir->subs);
	dir->subs = NULL;
}

gboolean ip_stop_watching  (ih_sub_t *sub)
{
	ip_watched_dir_t *dir = NULL;

	dir = g_hash_table_lookup (sub_dir_hash, sub);
	if (!dir) {
		return TRUE;
	}

	ip_unmap_sub_dir (sub, dir);

	/* No one is subscribing to this directory any more */
	if (dir->subs == NULL) {
		ik_ignore (dir->path, dir->wd);
		ip_unmap_wd_dir (dir->wd, dir);
		ip_unmap_path_dir (dir->path, dir);
		ip_watched_dir_free (dir);
	}

	return TRUE;
}


static ip_watched_dir_t *
ip_watched_dir_new (const char *path, gint32 wd)
{
	ip_watched_dir_t *dir = g_new0(ip_watched_dir_t, 1);

	dir->path = g_strdup(path);
	dir->wd = wd;

	return dir;
}

static void
ip_watched_dir_free (ip_watched_dir_t * dir)
{
	g_assert (dir->subs == NULL);
	g_free(dir->path);
	g_free(dir);
}

static void ip_wd_delete (gpointer data, gpointer user_data)
{
	ip_watched_dir_t *dir = data;
	GList *l = NULL;

	for (l = dir->subs; l; l = l->next)
	{
		ih_sub_t *sub = l->data;

		/* Add subscription to missing list */
		im_add (sub);
	}
	ip_unmap_all_subs (dir);
	/* Unassociate the path and the directory */
	ip_unmap_path_dir (dir->path, dir);
	ip_watched_dir_free (dir);
}

static void ip_event_dispatch (GList *dir_list, GList *pair_dir_list, ik_event_t *event)
{
	GList *dirl;

	if (!event)
		return;

	/* TODO:
	 *
	 * Figure out how we will deliver move events
	 */
	for (dirl = dir_list; dirl; dirl = dirl->next)
	{
		GList *subl;
		ip_watched_dir_t *dir = dirl->data;

		for (subl = dir->subs; subl; subl = subl->next)
		{
			ih_sub_t *sub = subl->data;

			/* If the event and the subscription have a filename
			 * they need to match before the event could be delivered.
			 */
			if (event->name && sub->filename) {
				if (strcmp (event->name, sub->filename))
					continue;
			/* If the event doesn't have a filename, but the subscription does
			 * we shouldn't deliever the event */
			} else if (sub->filename)
				continue;

			event_callback (event, sub);
		}
	}

	if (!event->pair)
		return;

	for (dirl = pair_dir_list; dirl; dirl = dirl->next)
	{
		GList *subl;
		ip_watched_dir_t *dir = dirl->data;

		for (subl = dir->subs; subl; subl = subl->next)
		{
			ih_sub_t *sub = subl->data;

			/* If the event and the subscription have a filename
			 * they need to match before the event could be delivered.
			 */
			if (event->pair->name && sub->filename) {
				if (strcmp (event->pair->name, sub->filename))
					continue;
			/* If the event doesn't have a filename, but the subscription does
			 * we shouldn't deliever the event */
			} else if (sub->filename)
				continue;

			event_callback (event->pair, sub);
		}
	}
}

static void
ip_event_callback (ik_event_t *event)
{
	GList *dir_list = NULL;
	GList *pair_dir_list = NULL;

	dir_list = g_hash_table_lookup (wd_dir_hash, GINT_TO_POINTER(event->wd));

	/* We can ignore IN_IGNORED events */
	if (event->mask & IN_IGNORED) {
		ik_event_free (event);
		return;
	}

	if (event->pair)
		pair_dir_list = g_hash_table_lookup (wd_dir_hash, GINT_TO_POINTER(event->pair->wd));

	if (event->mask & IP_INOTIFY_MASK)
		ip_event_dispatch (dir_list, pair_dir_list, event);

	/* We have to manage the missing list when we get a DELETE/UNMOUNT event. */
	if (event->mask & IN_DELETE_SELF || event->mask & IN_MOVE_SELF || event->mask & IN_UNMOUNT)
	{
		/* Add all subscriptions to missing list */
		g_list_foreach (dir_list, ip_wd_delete, NULL);
		/* Unmap all directories attached to this wd */
		ip_unmap_wd (event->wd);
	}

	ik_event_free (event);
}