1 /* -*- Mode: C; indent-tabs-mode: t; c-basic-offset: 2; tab-width: 8 -*- */ 2 3 /* inotify-path.c - GVFS Directory Monitor based on inotify. 4 5 Copyright (C) 2006 John McCutchan 6 7 The Gnome Library is free software; you can redistribute it and/or 8 modify it under the terms of the GNU Library General Public License as 9 published by the Free Software Foundation; either version 2 of the 10 License, or (at your option) any later version. 11 12 The Gnome Library is distributed in the hope that it will be useful, 13 but WITHOUT ANY WARRANTY; without even the implied warranty of 14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 15 Library General Public License for more details. 16 17 You should have received a copy of the GNU Library General Public 18 License along with the Gnome Library; see the file COPYING.LIB. If not, 19 write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, 20 Boston, MA 02111-1307, USA. 21 22 Authors: 23 John McCutchan <john (at) johnmccutchan.com> 24 */ 25 26 #include "config.h" 27 28 /* Don't put conflicting kernel types in the global namespace: */ 29 #define __KERNEL_STRICT_NAMES 30 31 #include <sys/inotify.h> 32 #include <string.h> 33 #include <glib.h> 34 #include "inotify-kernel.h" 35 #include "inotify-path.h" 36 #include "inotify-missing.h" 37 38 #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|IN_CLOSE_WRITE) 39 40 /* Older libcs don't have this */ 41 #ifndef IN_ONLYDIR 42 #define IN_ONLYDIR 0 43 #endif 44 45 typedef struct ip_watched_dir_s { 46 char *path; 47 /* TODO: We need to maintain a tree of watched directories 48 * so that we can deliver move/delete events to sub folders. 49 * Or the application could do it... 50 */ 51 struct ip_watched_dir_s* parent; 52 GList* children; 53 54 /* Inotify state */ 55 gint32 wd; 56 57 /* List of inotify subscriptions */ 58 GList *subs; 59 } ip_watched_dir_t; 60 61 static gboolean ip_debug_enabled = FALSE; 62 #define IP_W if (ip_debug_enabled) g_warning 63 64 /* path -> ip_watched_dir */ 65 static GHashTable * path_dir_hash = NULL; 66 /* inotify_sub * -> ip_watched_dir * 67 * 68 * Each subscription is attached to a watched directory or it is on 69 * the missing list 70 */ 71 static GHashTable * sub_dir_hash = NULL; 72 /* This hash holds GLists of ip_watched_dir_t *'s 73 * We need to hold a list because symbolic links can share 74 * the same wd 75 */ 76 static GHashTable * wd_dir_hash = NULL; 77 78 static ip_watched_dir_t *ip_watched_dir_new (const char *path, 79 int wd); 80 static void ip_watched_dir_free (ip_watched_dir_t *dir); 81 static void ip_event_callback (ik_event_t *event); 82 83 84 static void (*event_callback)(ik_event_t *event, inotify_sub *sub); 85 86 gboolean 87 _ip_startup (void (*cb)(ik_event_t *event, inotify_sub *sub)) 88 { 89 static gboolean initialized = FALSE; 90 static gboolean result = FALSE; 91 92 if (initialized == TRUE) 93 return result; 94 95 event_callback = cb; 96 result = _ik_startup (ip_event_callback); 97 98 if (!result) 99 return FALSE; 100 101 path_dir_hash = g_hash_table_new (g_str_hash, g_str_equal); 102 sub_dir_hash = g_hash_table_new (g_direct_hash, g_direct_equal); 103 wd_dir_hash = g_hash_table_new (g_direct_hash, g_direct_equal); 104 105 initialized = TRUE; 106 return TRUE; 107 } 108 109 static void 110 ip_map_path_dir (const char *path, 111 ip_watched_dir_t *dir) 112 { 113 g_assert (path && dir); 114 g_hash_table_insert (path_dir_hash, dir->path, dir); 115 } 116 117 static void 118 ip_map_sub_dir (inotify_sub *sub, 119 ip_watched_dir_t *dir) 120 { 121 /* Associate subscription and directory */ 122 g_assert (dir && sub); 123 g_hash_table_insert (sub_dir_hash, sub, dir); 124 dir->subs = g_list_prepend (dir->subs, sub); 125 } 126 127 static void 128 ip_map_wd_dir (gint32 wd, 129 ip_watched_dir_t *dir) 130 { 131 GList *dir_list; 132 133 g_assert (wd >= 0 && dir); 134 dir_list = g_hash_table_lookup (wd_dir_hash, GINT_TO_POINTER (wd)); 135 dir_list = g_list_prepend (dir_list, dir); 136 g_hash_table_replace (wd_dir_hash, GINT_TO_POINTER (dir->wd), dir_list); 137 } 138 139 gboolean 140 _ip_start_watching (inotify_sub *sub) 141 { 142 gint32 wd; 143 int err; 144 ip_watched_dir_t *dir; 145 146 g_assert (sub); 147 g_assert (!sub->cancelled); 148 g_assert (sub->dirname); 149 150 IP_W ("Starting to watch %s\n", sub->dirname); 151 dir = g_hash_table_lookup (path_dir_hash, sub->dirname); 152 if (dir) 153 { 154 IP_W ("Already watching\n"); 155 goto out; 156 } 157 158 IP_W ("Trying to add inotify watch "); 159 wd = _ik_watch (sub->dirname, IP_INOTIFY_MASK|IN_ONLYDIR, &err); 160 if (wd < 0) 161 { 162 IP_W ("Failed\n"); 163 return FALSE; 164 } 165 else 166 { 167 /* Create new watched directory and associate it with the 168 * wd hash and path hash 169 */ 170 IP_W ("Success\n"); 171 dir = ip_watched_dir_new (sub->dirname, wd); 172 ip_map_wd_dir (wd, dir); 173 ip_map_path_dir (sub->dirname, dir); 174 } 175 176 out: 177 ip_map_sub_dir (sub, dir); 178 179 return TRUE; 180 } 181 182 static void 183 ip_unmap_path_dir (const char *path, 184 ip_watched_dir_t *dir) 185 { 186 g_assert (path && dir); 187 g_hash_table_remove (path_dir_hash, dir->path); 188 } 189 190 static void 191 ip_unmap_wd_dir (gint32 wd, 192 ip_watched_dir_t *dir) 193 { 194 GList *dir_list = g_hash_table_lookup (wd_dir_hash, GINT_TO_POINTER (wd)); 195 196 if (!dir_list) 197 return; 198 199 g_assert (wd >= 0 && dir); 200 dir_list = g_list_remove (dir_list, dir); 201 if (dir_list == NULL) 202 g_hash_table_remove (wd_dir_hash, GINT_TO_POINTER (dir->wd)); 203 else 204 g_hash_table_replace (wd_dir_hash, GINT_TO_POINTER (dir->wd), dir_list); 205 } 206 207 static void 208 ip_unmap_wd (gint32 wd) 209 { 210 GList *dir_list = g_hash_table_lookup (wd_dir_hash, GINT_TO_POINTER (wd)); 211 if (!dir_list) 212 return; 213 g_assert (wd >= 0); 214 g_hash_table_remove (wd_dir_hash, GINT_TO_POINTER (wd)); 215 g_list_free (dir_list); 216 } 217 218 static void 219 ip_unmap_sub_dir (inotify_sub *sub, 220 ip_watched_dir_t *dir) 221 { 222 g_assert (sub && dir); 223 g_hash_table_remove (sub_dir_hash, sub); 224 dir->subs = g_list_remove (dir->subs, sub); 225 } 226 227 static void 228 ip_unmap_all_subs (ip_watched_dir_t *dir) 229 { 230 GList *l = NULL; 231 232 for (l = dir->subs; l; l = l->next) 233 { 234 inotify_sub *sub = l->data; 235 g_hash_table_remove (sub_dir_hash, sub); 236 } 237 g_list_free (dir->subs); 238 dir->subs = NULL; 239 } 240 241 gboolean 242 _ip_stop_watching (inotify_sub *sub) 243 { 244 ip_watched_dir_t *dir = NULL; 245 246 dir = g_hash_table_lookup (sub_dir_hash, sub); 247 if (!dir) 248 return TRUE; 249 250 ip_unmap_sub_dir (sub, dir); 251 252 /* No one is subscribing to this directory any more */ 253 if (dir->subs == NULL) 254 { 255 _ik_ignore (dir->path, dir->wd); 256 ip_unmap_wd_dir (dir->wd, dir); 257 ip_unmap_path_dir (dir->path, dir); 258 ip_watched_dir_free (dir); 259 } 260 261 return TRUE; 262 } 263 264 265 static ip_watched_dir_t * 266 ip_watched_dir_new (const char *path, 267 gint32 wd) 268 { 269 ip_watched_dir_t *dir = g_new0 (ip_watched_dir_t, 1); 270 271 dir->path = g_strdup (path); 272 dir->wd = wd; 273 274 return dir; 275 } 276 277 static void 278 ip_watched_dir_free (ip_watched_dir_t *dir) 279 { 280 g_assert (dir->subs == NULL); 281 g_free (dir->path); 282 g_free (dir); 283 } 284 285 static void 286 ip_wd_delete (gpointer data, 287 gpointer user_data) 288 { 289 ip_watched_dir_t *dir = data; 290 GList *l = NULL; 291 292 for (l = dir->subs; l; l = l->next) 293 { 294 inotify_sub *sub = l->data; 295 /* Add subscription to missing list */ 296 _im_add (sub); 297 } 298 ip_unmap_all_subs (dir); 299 /* Unassociate the path and the directory */ 300 ip_unmap_path_dir (dir->path, dir); 301 ip_watched_dir_free (dir); 302 } 303 304 static void 305 ip_event_dispatch (GList *dir_list, 306 GList *pair_dir_list, 307 ik_event_t *event) 308 { 309 GList *dirl; 310 311 if (!event) 312 return; 313 314 for (dirl = dir_list; dirl; dirl = dirl->next) 315 { 316 GList *subl; 317 ip_watched_dir_t *dir = dirl->data; 318 319 for (subl = dir->subs; subl; subl = subl->next) 320 { 321 inotify_sub *sub = subl->data; 322 323 /* If the subscription and the event 324 * contain a filename and they don't 325 * match, we don't deliver this event. 326 */ 327 if (sub->filename && 328 event->name && 329 strcmp (sub->filename, event->name)) 330 continue; 331 332 /* If the subscription has a filename 333 * but this event doesn't, we don't 334 * deliever this event. 335 */ 336 if (sub->filename && !event->name) 337 continue; 338 339 /* FIXME: We might need to synthesize 340 * DELETE/UNMOUNT events when 341 * the filename doesn't match 342 */ 343 344 event_callback (event, sub); 345 } 346 } 347 348 if (!event->pair) 349 return; 350 351 for (dirl = pair_dir_list; dirl; dirl = dirl->next) 352 { 353 GList *subl; 354 ip_watched_dir_t *dir = dirl->data; 355 356 for (subl = dir->subs; subl; subl = subl->next) 357 { 358 inotify_sub *sub = subl->data; 359 360 /* If the subscription and the event 361 * contain a filename and they don't 362 * match, we don't deliver this event. 363 */ 364 if (sub->filename && 365 event->pair->name && 366 strcmp (sub->filename, event->pair->name)) 367 continue; 368 369 /* If the subscription has a filename 370 * but this event doesn't, we don't 371 * deliever this event. 372 */ 373 if (sub->filename && !event->pair->name) 374 continue; 375 376 /* FIXME: We might need to synthesize 377 * DELETE/UNMOUNT events when 378 * the filename doesn't match 379 */ 380 381 event_callback (event->pair, sub); 382 } 383 } 384 } 385 386 static void 387 ip_event_callback (ik_event_t *event) 388 { 389 GList* dir_list = NULL; 390 GList* pair_dir_list = NULL; 391 392 dir_list = g_hash_table_lookup (wd_dir_hash, GINT_TO_POINTER (event->wd)); 393 394 /* We can ignore the IGNORED events */ 395 if (event->mask & IN_IGNORED) 396 { 397 _ik_event_free (event); 398 return; 399 } 400 401 if (event->pair) 402 pair_dir_list = g_hash_table_lookup (wd_dir_hash, GINT_TO_POINTER (event->pair->wd)); 403 404 if (event->mask & IP_INOTIFY_MASK) 405 ip_event_dispatch (dir_list, pair_dir_list, event); 406 407 /* We have to manage the missing list 408 * when we get an event that means the 409 * file has been deleted/moved/unmounted. 410 */ 411 if (event->mask & IN_DELETE_SELF || 412 event->mask & IN_MOVE_SELF || 413 event->mask & IN_UNMOUNT) 414 { 415 /* Add all subscriptions to missing list */ 416 g_list_foreach (dir_list, ip_wd_delete, NULL); 417 /* Unmap all directories attached to this wd */ 418 ip_unmap_wd (event->wd); 419 } 420 421 _ik_event_free (event); 422 } 423