Emeric Vigier | 2f62582 | 2012-08-06 11:09:52 -0400 | [diff] [blame] | 1 | /* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */ |
| 2 | /* expirelist.c List of items that expire |
| 3 | * |
| 4 | * Copyright (C) 2003 Red Hat, Inc. |
| 5 | * |
| 6 | * Licensed under the Academic Free License version 2.1 |
| 7 | * |
| 8 | * This program is free software; you can redistribute it and/or modify |
| 9 | * it under the terms of the GNU General Public License as published by |
| 10 | * the Free Software Foundation; either version 2 of the License, or |
| 11 | * (at your option) any later version. |
| 12 | * |
| 13 | * This program is distributed in the hope that it will be useful, |
| 14 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 15 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 16 | * GNU General Public License for more details. |
| 17 | * |
| 18 | * You should have received a copy of the GNU General Public License |
| 19 | * along with this program; if not, write to the Free Software |
| 20 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| 21 | * |
| 22 | */ |
| 23 | |
| 24 | #include <config.h> |
| 25 | #include "expirelist.h" |
| 26 | #include "test.h" |
| 27 | #include <dbus/dbus-internals.h> |
| 28 | #include <dbus/dbus-mainloop.h> |
| 29 | #include <dbus/dbus-timeout.h> |
| 30 | |
| 31 | struct BusExpireList |
| 32 | { |
| 33 | DBusList *items; /**< List of BusExpireItem */ |
| 34 | DBusTimeout *timeout; |
| 35 | DBusLoop *loop; |
| 36 | BusExpireFunc expire_func; |
| 37 | void *data; |
| 38 | int expire_after; /**< Expire after milliseconds (thousandths) */ |
| 39 | }; |
| 40 | |
| 41 | static dbus_bool_t expire_timeout_handler (void *data); |
| 42 | |
| 43 | static void |
| 44 | call_timeout_callback (DBusTimeout *timeout, |
| 45 | void *data) |
| 46 | { |
| 47 | /* can return FALSE on OOM but we just let it fire again later */ |
| 48 | dbus_timeout_handle (timeout); |
| 49 | } |
| 50 | |
| 51 | BusExpireList* |
| 52 | bus_expire_list_new (DBusLoop *loop, |
| 53 | int expire_after, |
| 54 | BusExpireFunc expire_func, |
| 55 | void *data) |
| 56 | { |
| 57 | BusExpireList *list; |
| 58 | |
| 59 | list = dbus_new0 (BusExpireList, 1); |
| 60 | if (list == NULL) |
| 61 | return NULL; |
| 62 | |
| 63 | list->expire_func = expire_func; |
| 64 | list->data = data; |
| 65 | list->loop = loop; |
| 66 | list->expire_after = expire_after; |
| 67 | |
| 68 | list->timeout = _dbus_timeout_new (100, /* irrelevant */ |
| 69 | expire_timeout_handler, |
| 70 | list, NULL); |
| 71 | if (list->timeout == NULL) |
| 72 | goto failed; |
| 73 | |
| 74 | _dbus_timeout_set_enabled (list->timeout, FALSE); |
| 75 | |
| 76 | if (!_dbus_loop_add_timeout (list->loop, |
| 77 | list->timeout, |
| 78 | call_timeout_callback, NULL, NULL)) |
| 79 | goto failed; |
| 80 | |
| 81 | return list; |
| 82 | |
| 83 | failed: |
| 84 | if (list->timeout) |
| 85 | _dbus_timeout_unref (list->timeout); |
| 86 | |
| 87 | dbus_free (list); |
| 88 | |
| 89 | return NULL; |
| 90 | } |
| 91 | |
| 92 | void |
| 93 | bus_expire_list_free (BusExpireList *list) |
| 94 | { |
| 95 | _dbus_assert (list->items == NULL); |
| 96 | |
| 97 | _dbus_loop_remove_timeout (list->loop, list->timeout, |
| 98 | call_timeout_callback, NULL); |
| 99 | |
| 100 | _dbus_timeout_unref (list->timeout); |
| 101 | |
| 102 | dbus_free (list); |
| 103 | } |
| 104 | |
| 105 | void |
| 106 | bus_expire_timeout_set_interval (DBusTimeout *timeout, |
| 107 | int next_interval) |
| 108 | { |
| 109 | if (next_interval >= 0) |
| 110 | { |
| 111 | _dbus_timeout_set_interval (timeout, |
| 112 | next_interval); |
| 113 | _dbus_timeout_set_enabled (timeout, TRUE); |
| 114 | |
| 115 | _dbus_verbose ("Enabled an expire timeout with interval %d\n", |
| 116 | next_interval); |
| 117 | } |
| 118 | else if (dbus_timeout_get_enabled (timeout)) |
| 119 | { |
| 120 | _dbus_timeout_set_enabled (timeout, FALSE); |
| 121 | |
| 122 | _dbus_verbose ("Disabled an expire timeout\n"); |
| 123 | } |
| 124 | else |
| 125 | _dbus_verbose ("No need to disable this expire timeout\n"); |
| 126 | } |
| 127 | |
| 128 | void |
| 129 | bus_expire_list_recheck_immediately (BusExpireList *list) |
| 130 | { |
| 131 | _dbus_verbose ("setting interval on expire list to 0 for immediate recheck\n"); |
| 132 | |
| 133 | bus_expire_timeout_set_interval (list->timeout, 0); |
| 134 | } |
| 135 | |
| 136 | static int |
| 137 | do_expiration_with_current_time (BusExpireList *list, |
| 138 | long tv_sec, |
| 139 | long tv_usec) |
| 140 | { |
| 141 | DBusList *link; |
| 142 | int next_interval, min_wait_time, items_to_expire; |
| 143 | |
| 144 | next_interval = -1; |
| 145 | min_wait_time = 3600 * 1000; /* this is reset anyway if used */ |
| 146 | items_to_expire = 0; |
| 147 | |
| 148 | link = _dbus_list_get_first_link (&list->items); |
| 149 | while (link != NULL) |
| 150 | { |
| 151 | DBusList *next = _dbus_list_get_next_link (&list->items, link); |
| 152 | double elapsed; |
| 153 | BusExpireItem *item; |
| 154 | |
| 155 | item = link->data; |
| 156 | |
| 157 | elapsed = ELAPSED_MILLISECONDS_SINCE (item->added_tv_sec, |
| 158 | item->added_tv_usec, |
| 159 | tv_sec, tv_usec); |
| 160 | |
| 161 | if (((item->added_tv_sec == 0) && (item->added_tv_usec == 0)) || |
| 162 | ((list->expire_after > 0) && (elapsed >= (double) list->expire_after))) |
| 163 | { |
| 164 | _dbus_verbose ("Expiring an item %p\n", item); |
| 165 | |
| 166 | /* If the expire function fails, we just end up expiring |
| 167 | * this item next time we walk through the list. This would |
| 168 | * be an indeterminate time normally, so we set up the |
| 169 | * next_interval to be "shortly" (just enough to avoid |
| 170 | * a busy loop) |
| 171 | */ |
| 172 | if (!(* list->expire_func) (list, link, list->data)) |
| 173 | { |
| 174 | next_interval = _dbus_get_oom_wait (); |
| 175 | break; |
| 176 | } |
| 177 | } |
| 178 | else if (list->expire_after > 0) |
| 179 | { |
| 180 | double to_wait; |
| 181 | |
| 182 | items_to_expire = 1; |
| 183 | to_wait = (double) list->expire_after - elapsed; |
| 184 | if (min_wait_time > to_wait) |
| 185 | min_wait_time = to_wait; |
| 186 | } |
| 187 | |
| 188 | link = next; |
| 189 | } |
| 190 | |
| 191 | if (next_interval < 0 && items_to_expire) |
| 192 | next_interval = min_wait_time; |
| 193 | |
| 194 | return next_interval; |
| 195 | } |
| 196 | |
| 197 | static void |
| 198 | bus_expirelist_expire (BusExpireList *list) |
| 199 | { |
| 200 | int next_interval; |
| 201 | |
| 202 | next_interval = -1; |
| 203 | |
| 204 | if (list->items != NULL) |
| 205 | { |
| 206 | long tv_sec, tv_usec; |
| 207 | |
| 208 | _dbus_get_current_time (&tv_sec, &tv_usec); |
| 209 | |
| 210 | next_interval = do_expiration_with_current_time (list, tv_sec, tv_usec); |
| 211 | } |
| 212 | |
| 213 | bus_expire_timeout_set_interval (list->timeout, next_interval); |
| 214 | } |
| 215 | |
| 216 | static dbus_bool_t |
| 217 | expire_timeout_handler (void *data) |
| 218 | { |
| 219 | BusExpireList *list = data; |
| 220 | |
| 221 | _dbus_verbose ("Running\n"); |
| 222 | |
| 223 | /* note that this may remove the timeout */ |
| 224 | bus_expirelist_expire (list); |
| 225 | |
| 226 | return TRUE; |
| 227 | } |
| 228 | |
| 229 | void |
| 230 | bus_expire_list_remove_link (BusExpireList *list, |
| 231 | DBusList *link) |
| 232 | { |
| 233 | _dbus_list_remove_link (&list->items, link); |
| 234 | } |
| 235 | |
| 236 | dbus_bool_t |
| 237 | bus_expire_list_remove (BusExpireList *list, |
| 238 | BusExpireItem *item) |
| 239 | { |
| 240 | return _dbus_list_remove (&list->items, item); |
| 241 | } |
| 242 | |
| 243 | void |
| 244 | bus_expire_list_unlink (BusExpireList *list, |
| 245 | DBusList *link) |
| 246 | { |
| 247 | _dbus_list_unlink (&list->items, link); |
| 248 | } |
| 249 | |
| 250 | dbus_bool_t |
| 251 | bus_expire_list_add (BusExpireList *list, |
| 252 | BusExpireItem *item) |
| 253 | { |
| 254 | dbus_bool_t ret; |
| 255 | |
| 256 | ret = _dbus_list_prepend (&list->items, item); |
| 257 | if (ret && !dbus_timeout_get_enabled (list->timeout)) |
| 258 | bus_expire_timeout_set_interval (list->timeout, 0); |
| 259 | |
| 260 | return ret; |
| 261 | } |
| 262 | |
| 263 | void |
| 264 | bus_expire_list_add_link (BusExpireList *list, |
| 265 | DBusList *link) |
| 266 | { |
| 267 | _dbus_assert (link->data != NULL); |
| 268 | |
| 269 | _dbus_list_prepend_link (&list->items, link); |
| 270 | |
| 271 | if (!dbus_timeout_get_enabled (list->timeout)) |
| 272 | bus_expire_timeout_set_interval (list->timeout, 0); |
| 273 | } |
| 274 | |
| 275 | DBusList* |
| 276 | bus_expire_list_get_first_link (BusExpireList *list) |
| 277 | { |
| 278 | return _dbus_list_get_first_link (&list->items); |
| 279 | } |
| 280 | |
| 281 | DBusList* |
| 282 | bus_expire_list_get_next_link (BusExpireList *list, |
| 283 | DBusList *link) |
| 284 | { |
| 285 | return _dbus_list_get_next_link (&list->items, link); |
| 286 | } |
| 287 | |
| 288 | dbus_bool_t |
| 289 | bus_expire_list_contains_item (BusExpireList *list, |
| 290 | BusExpireItem *item) |
| 291 | { |
| 292 | return _dbus_list_find_last (&list->items, item) != NULL; |
| 293 | } |
| 294 | |
| 295 | #ifdef DBUS_BUILD_TESTS |
| 296 | |
| 297 | typedef struct |
| 298 | { |
| 299 | BusExpireItem item; |
| 300 | int expire_count; |
| 301 | } TestExpireItem; |
| 302 | |
| 303 | static dbus_bool_t |
| 304 | test_expire_func (BusExpireList *list, |
| 305 | DBusList *link, |
| 306 | void *data) |
| 307 | { |
| 308 | TestExpireItem *t; |
| 309 | |
| 310 | t = (TestExpireItem*) link->data; |
| 311 | |
| 312 | t->expire_count += 1; |
| 313 | |
| 314 | return TRUE; |
| 315 | } |
| 316 | |
| 317 | static void |
| 318 | time_add_milliseconds (long *tv_sec, |
| 319 | long *tv_usec, |
| 320 | int milliseconds) |
| 321 | { |
| 322 | *tv_sec = *tv_sec + milliseconds / 1000; |
| 323 | *tv_usec = *tv_usec + milliseconds * 1000; |
| 324 | if (*tv_usec >= 1000000) |
| 325 | { |
| 326 | *tv_usec -= 1000000; |
| 327 | *tv_sec += 1; |
| 328 | } |
| 329 | } |
| 330 | |
| 331 | dbus_bool_t |
| 332 | bus_expire_list_test (const DBusString *test_data_dir) |
| 333 | { |
| 334 | DBusLoop *loop; |
| 335 | BusExpireList *list; |
| 336 | long tv_sec, tv_usec; |
| 337 | long tv_sec_not_expired, tv_usec_not_expired; |
| 338 | long tv_sec_expired, tv_usec_expired; |
| 339 | long tv_sec_past, tv_usec_past; |
| 340 | TestExpireItem *item; |
| 341 | int next_interval; |
| 342 | dbus_bool_t result = FALSE; |
| 343 | |
| 344 | |
| 345 | loop = _dbus_loop_new (); |
| 346 | _dbus_assert (loop != NULL); |
| 347 | |
| 348 | #define EXPIRE_AFTER 100 |
| 349 | |
| 350 | list = bus_expire_list_new (loop, EXPIRE_AFTER, |
| 351 | test_expire_func, NULL); |
| 352 | _dbus_assert (list != NULL); |
| 353 | |
| 354 | _dbus_get_current_time (&tv_sec, &tv_usec); |
| 355 | |
| 356 | tv_sec_not_expired = tv_sec; |
| 357 | tv_usec_not_expired = tv_usec; |
| 358 | time_add_milliseconds (&tv_sec_not_expired, |
| 359 | &tv_usec_not_expired, EXPIRE_AFTER - 1); |
| 360 | |
| 361 | tv_sec_expired = tv_sec; |
| 362 | tv_usec_expired = tv_usec; |
| 363 | time_add_milliseconds (&tv_sec_expired, |
| 364 | &tv_usec_expired, EXPIRE_AFTER); |
| 365 | |
| 366 | |
| 367 | tv_sec_past = tv_sec - 1; |
| 368 | tv_usec_past = tv_usec; |
| 369 | |
| 370 | item = dbus_new0 (TestExpireItem, 1); |
| 371 | |
| 372 | if (item == NULL) |
| 373 | goto oom; |
| 374 | |
| 375 | item->item.added_tv_sec = tv_sec; |
| 376 | item->item.added_tv_usec = tv_usec; |
| 377 | if (!bus_expire_list_add (list, &item->item)) |
| 378 | _dbus_assert_not_reached ("out of memory"); |
| 379 | |
| 380 | next_interval = |
| 381 | do_expiration_with_current_time (list, tv_sec_not_expired, |
| 382 | tv_usec_not_expired); |
| 383 | _dbus_assert (item->expire_count == 0); |
| 384 | _dbus_verbose ("next_interval = %d\n", next_interval); |
| 385 | _dbus_assert (next_interval == 1); |
| 386 | |
| 387 | next_interval = |
| 388 | do_expiration_with_current_time (list, tv_sec_expired, |
| 389 | tv_usec_expired); |
| 390 | _dbus_assert (item->expire_count == 1); |
| 391 | _dbus_verbose ("next_interval = %d\n", next_interval); |
| 392 | _dbus_assert (next_interval == -1); |
| 393 | |
| 394 | next_interval = |
| 395 | do_expiration_with_current_time (list, tv_sec_past, |
| 396 | tv_usec_past); |
| 397 | _dbus_assert (item->expire_count == 1); |
| 398 | _dbus_verbose ("next_interval = %d\n", next_interval); |
| 399 | _dbus_assert (next_interval == 1000 + EXPIRE_AFTER); |
| 400 | |
| 401 | bus_expire_list_remove (list, &item->item); |
| 402 | dbus_free (item); |
| 403 | |
| 404 | bus_expire_list_free (list); |
| 405 | _dbus_loop_unref (loop); |
| 406 | |
| 407 | result = TRUE; |
| 408 | |
| 409 | oom: |
| 410 | return result; |
| 411 | } |
| 412 | |
| 413 | #endif /* DBUS_BUILD_TESTS */ |