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6543 Fix memory leak in uu_avl_pool_destroy
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--- old/usr/src/lib/libuutil/common/uu_avl.c
+++ new/usr/src/lib/libuutil/common/uu_avl.c
1 1 /*
2 2 * CDDL HEADER START
3 3 *
4 4 * The contents of this file are subject to the terms of the
5 5 * Common Development and Distribution License (the "License").
6 6 * You may not use this file except in compliance with the License.
7 7 *
8 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 9 * or http://www.opensolaris.org/os/licensing.
10 10 * See the License for the specific language governing permissions
11 11 * and limitations under the License.
12 12 *
13 13 * When distributing Covered Code, include this CDDL HEADER in each
14 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 15 * If applicable, add the following below this CDDL HEADER, with the
16 16 * fields enclosed by brackets "[]" replaced with your own identifying
17 17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 18 *
19 19 * CDDL HEADER END
20 20 */
21 21 /*
22 22 * Copyright 2008 Sun Microsystems, Inc. All rights reserved.
23 23 * Use is subject to license terms.
24 24 */
25 25
26 26 #pragma ident "%Z%%M% %I% %E% SMI"
27 27
28 28 #include "libuutil_common.h"
29 29
30 30 #include <stdlib.h>
31 31 #include <string.h>
32 32 #include <unistd.h>
33 33 #include <sys/avl.h>
34 34
35 35 static uu_avl_pool_t uu_null_apool = { &uu_null_apool, &uu_null_apool };
36 36 static pthread_mutex_t uu_apool_list_lock = PTHREAD_MUTEX_INITIALIZER;
37 37
38 38 /*
39 39 * The index mark change on every insert and delete, to catch stale
40 40 * references.
41 41 *
42 42 * We leave the low bit alone, since the avl code uses it.
43 43 */
44 44 #define INDEX_MAX (sizeof (uintptr_t) - 2)
45 45 #define INDEX_NEXT(m) (((m) == INDEX_MAX)? 2 : ((m) + 2) & INDEX_MAX)
46 46
47 47 #define INDEX_DECODE(i) ((i) & ~INDEX_MAX)
48 48 #define INDEX_ENCODE(p, n) (((n) & ~INDEX_MAX) | (p)->ua_index)
49 49 #define INDEX_VALID(p, i) (((i) & INDEX_MAX) == (p)->ua_index)
50 50 #define INDEX_CHECK(i) (((i) & INDEX_MAX) != 0)
51 51
52 52 /*
53 53 * When an element is inactive (not in a tree), we keep a marked pointer to
54 54 * its containing pool in its first word, and a NULL pointer in its second.
55 55 *
56 56 * On insert, we use these to verify that it comes from the correct pool.
57 57 */
58 58 #define NODE_ARRAY(p, n) ((uintptr_t *)((uintptr_t)(n) + \
59 59 (pp)->uap_nodeoffset))
60 60
61 61 #define POOL_TO_MARKER(pp) (((uintptr_t)(pp) | 1))
62 62
63 63 #define DEAD_MARKER 0xc4
64 64
65 65 uu_avl_pool_t *
66 66 uu_avl_pool_create(const char *name, size_t objsize, size_t nodeoffset,
67 67 uu_compare_fn_t *compare_func, uint32_t flags)
68 68 {
69 69 uu_avl_pool_t *pp, *next, *prev;
70 70
71 71 if (name == NULL ||
72 72 uu_check_name(name, UU_NAME_DOMAIN) == -1 ||
73 73 nodeoffset + sizeof (uu_avl_node_t) > objsize ||
74 74 compare_func == NULL) {
75 75 uu_set_error(UU_ERROR_INVALID_ARGUMENT);
76 76 return (NULL);
77 77 }
78 78
79 79 if (flags & ~UU_AVL_POOL_DEBUG) {
80 80 uu_set_error(UU_ERROR_UNKNOWN_FLAG);
81 81 return (NULL);
82 82 }
83 83
84 84 pp = uu_zalloc(sizeof (uu_avl_pool_t));
85 85 if (pp == NULL) {
86 86 uu_set_error(UU_ERROR_NO_MEMORY);
87 87 return (NULL);
88 88 }
89 89
90 90 (void) strlcpy(pp->uap_name, name, sizeof (pp->uap_name));
91 91 pp->uap_nodeoffset = nodeoffset;
92 92 pp->uap_objsize = objsize;
93 93 pp->uap_cmp = compare_func;
94 94 if (flags & UU_AVL_POOL_DEBUG)
95 95 pp->uap_debug = 1;
96 96 pp->uap_last_index = 0;
97 97
98 98 (void) pthread_mutex_init(&pp->uap_lock, NULL);
99 99
100 100 pp->uap_null_avl.ua_next_enc = UU_PTR_ENCODE(&pp->uap_null_avl);
101 101 pp->uap_null_avl.ua_prev_enc = UU_PTR_ENCODE(&pp->uap_null_avl);
102 102
103 103 (void) pthread_mutex_lock(&uu_apool_list_lock);
104 104 pp->uap_next = next = &uu_null_apool;
105 105 pp->uap_prev = prev = next->uap_prev;
106 106 next->uap_prev = pp;
107 107 prev->uap_next = pp;
108 108 (void) pthread_mutex_unlock(&uu_apool_list_lock);
109 109
110 110 return (pp);
111 111 }
112 112
113 113 void
114 114 uu_avl_pool_destroy(uu_avl_pool_t *pp)
115 115 {
116 116 if (pp->uap_debug) {
117 117 if (pp->uap_null_avl.ua_next_enc !=
118 118 UU_PTR_ENCODE(&pp->uap_null_avl) ||
119 119 pp->uap_null_avl.ua_prev_enc !=
120 120 UU_PTR_ENCODE(&pp->uap_null_avl)) {
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121 121 uu_panic("uu_avl_pool_destroy: Pool \"%.*s\" (%p) has "
122 122 "outstanding avls, or is corrupt.\n",
123 123 (int)sizeof (pp->uap_name), pp->uap_name,
124 124 (void *)pp);
125 125 }
126 126 }
127 127 (void) pthread_mutex_lock(&uu_apool_list_lock);
128 128 pp->uap_next->uap_prev = pp->uap_prev;
129 129 pp->uap_prev->uap_next = pp->uap_next;
130 130 (void) pthread_mutex_unlock(&uu_apool_list_lock);
131 + (void) pthread_mutex_destroy(&pp->uap_lock);
131 132 pp->uap_prev = NULL;
132 133 pp->uap_next = NULL;
133 134 uu_free(pp);
134 135 }
135 136
136 137 void
137 138 uu_avl_node_init(void *base, uu_avl_node_t *np, uu_avl_pool_t *pp)
138 139 {
139 140 uintptr_t *na = (uintptr_t *)np;
140 141
141 142 if (pp->uap_debug) {
142 143 uintptr_t offset = (uintptr_t)np - (uintptr_t)base;
143 144 if (offset + sizeof (*np) > pp->uap_objsize) {
144 145 uu_panic("uu_avl_node_init(%p, %p, %p (\"%s\")): "
145 146 "offset %ld doesn't fit in object (size %ld)\n",
146 147 base, (void *)np, (void *)pp, pp->uap_name,
147 148 (long)offset, (long)pp->uap_objsize);
148 149 }
149 150 if (offset != pp->uap_nodeoffset) {
150 151 uu_panic("uu_avl_node_init(%p, %p, %p (\"%s\")): "
151 152 "offset %ld doesn't match pool's offset (%ld)\n",
152 153 base, (void *)np, (void *)pp, pp->uap_name,
153 154 (long)offset, (long)pp->uap_objsize);
154 155 }
155 156 }
156 157
157 158 na[0] = POOL_TO_MARKER(pp);
158 159 na[1] = 0;
159 160 }
160 161
161 162 void
162 163 uu_avl_node_fini(void *base, uu_avl_node_t *np, uu_avl_pool_t *pp)
163 164 {
164 165 uintptr_t *na = (uintptr_t *)np;
165 166
166 167 if (pp->uap_debug) {
167 168 if (na[0] == DEAD_MARKER && na[1] == DEAD_MARKER) {
168 169 uu_panic("uu_avl_node_fini(%p, %p, %p (\"%s\")): "
169 170 "node already finied\n",
170 171 base, (void *)np, (void *)pp, pp->uap_name);
171 172 }
172 173 if (na[0] != POOL_TO_MARKER(pp) || na[1] != 0) {
173 174 uu_panic("uu_avl_node_fini(%p, %p, %p (\"%s\")): "
174 175 "node corrupt, in tree, or in different pool\n",
175 176 base, (void *)np, (void *)pp, pp->uap_name);
176 177 }
177 178 }
178 179
179 180 na[0] = DEAD_MARKER;
180 181 na[1] = DEAD_MARKER;
181 182 na[2] = DEAD_MARKER;
182 183 }
183 184
184 185 struct uu_avl_node_compare_info {
185 186 uu_compare_fn_t *ac_compare;
186 187 void *ac_private;
187 188 void *ac_right;
188 189 void *ac_found;
189 190 };
190 191
191 192 static int
192 193 uu_avl_node_compare(const void *l, const void *r)
193 194 {
194 195 struct uu_avl_node_compare_info *info =
195 196 (struct uu_avl_node_compare_info *)l;
196 197
197 198 int res = info->ac_compare(r, info->ac_right, info->ac_private);
198 199
199 200 if (res == 0) {
200 201 if (info->ac_found == NULL)
201 202 info->ac_found = (void *)r;
202 203 return (-1);
203 204 }
204 205 if (res < 0)
205 206 return (1);
206 207 return (-1);
207 208 }
208 209
209 210 uu_avl_t *
210 211 uu_avl_create(uu_avl_pool_t *pp, void *parent, uint32_t flags)
211 212 {
212 213 uu_avl_t *ap, *next, *prev;
213 214
214 215 if (flags & ~UU_AVL_DEBUG) {
215 216 uu_set_error(UU_ERROR_UNKNOWN_FLAG);
216 217 return (NULL);
217 218 }
218 219
219 220 ap = uu_zalloc(sizeof (*ap));
220 221 if (ap == NULL) {
221 222 uu_set_error(UU_ERROR_NO_MEMORY);
222 223 return (NULL);
223 224 }
224 225
225 226 ap->ua_pool = pp;
226 227 ap->ua_parent_enc = UU_PTR_ENCODE(parent);
227 228 ap->ua_debug = pp->uap_debug || (flags & UU_AVL_DEBUG);
228 229 ap->ua_index = (pp->uap_last_index = INDEX_NEXT(pp->uap_last_index));
229 230
230 231 avl_create(&ap->ua_tree, &uu_avl_node_compare, pp->uap_objsize,
231 232 pp->uap_nodeoffset);
232 233
233 234 ap->ua_null_walk.uaw_next = &ap->ua_null_walk;
234 235 ap->ua_null_walk.uaw_prev = &ap->ua_null_walk;
235 236
236 237 (void) pthread_mutex_lock(&pp->uap_lock);
237 238 next = &pp->uap_null_avl;
238 239 prev = UU_PTR_DECODE(next->ua_prev_enc);
239 240 ap->ua_next_enc = UU_PTR_ENCODE(next);
240 241 ap->ua_prev_enc = UU_PTR_ENCODE(prev);
241 242 next->ua_prev_enc = UU_PTR_ENCODE(ap);
242 243 prev->ua_next_enc = UU_PTR_ENCODE(ap);
243 244 (void) pthread_mutex_unlock(&pp->uap_lock);
244 245
245 246 return (ap);
246 247 }
247 248
248 249 void
249 250 uu_avl_destroy(uu_avl_t *ap)
250 251 {
251 252 uu_avl_pool_t *pp = ap->ua_pool;
252 253
253 254 if (ap->ua_debug) {
254 255 if (avl_numnodes(&ap->ua_tree) != 0) {
255 256 uu_panic("uu_avl_destroy(%p): tree not empty\n",
256 257 (void *)ap);
257 258 }
258 259 if (ap->ua_null_walk.uaw_next != &ap->ua_null_walk ||
259 260 ap->ua_null_walk.uaw_prev != &ap->ua_null_walk) {
260 261 uu_panic("uu_avl_destroy(%p): outstanding walkers\n",
261 262 (void *)ap);
262 263 }
263 264 }
264 265 (void) pthread_mutex_lock(&pp->uap_lock);
265 266 UU_AVL_PTR(ap->ua_next_enc)->ua_prev_enc = ap->ua_prev_enc;
266 267 UU_AVL_PTR(ap->ua_prev_enc)->ua_next_enc = ap->ua_next_enc;
267 268 (void) pthread_mutex_unlock(&pp->uap_lock);
268 269 ap->ua_prev_enc = UU_PTR_ENCODE(NULL);
269 270 ap->ua_next_enc = UU_PTR_ENCODE(NULL);
270 271
271 272 ap->ua_pool = NULL;
272 273 avl_destroy(&ap->ua_tree);
273 274
274 275 uu_free(ap);
275 276 }
276 277
277 278 size_t
278 279 uu_avl_numnodes(uu_avl_t *ap)
279 280 {
280 281 return (avl_numnodes(&ap->ua_tree));
281 282 }
282 283
283 284 void *
284 285 uu_avl_first(uu_avl_t *ap)
285 286 {
286 287 return (avl_first(&ap->ua_tree));
287 288 }
288 289
289 290 void *
290 291 uu_avl_last(uu_avl_t *ap)
291 292 {
292 293 return (avl_last(&ap->ua_tree));
293 294 }
294 295
295 296 void *
296 297 uu_avl_next(uu_avl_t *ap, void *node)
297 298 {
298 299 return (AVL_NEXT(&ap->ua_tree, node));
299 300 }
300 301
301 302 void *
302 303 uu_avl_prev(uu_avl_t *ap, void *node)
303 304 {
304 305 return (AVL_PREV(&ap->ua_tree, node));
305 306 }
306 307
307 308 static void
308 309 _avl_walk_init(uu_avl_walk_t *wp, uu_avl_t *ap, uint32_t flags)
309 310 {
310 311 uu_avl_walk_t *next, *prev;
311 312
312 313 int robust = (flags & UU_WALK_ROBUST);
313 314 int direction = (flags & UU_WALK_REVERSE)? -1 : 1;
314 315
315 316 (void) memset(wp, 0, sizeof (*wp));
316 317 wp->uaw_avl = ap;
317 318 wp->uaw_robust = robust;
318 319 wp->uaw_dir = direction;
319 320
320 321 if (direction > 0)
321 322 wp->uaw_next_result = avl_first(&ap->ua_tree);
322 323 else
323 324 wp->uaw_next_result = avl_last(&ap->ua_tree);
324 325
325 326 if (ap->ua_debug || robust) {
326 327 wp->uaw_next = next = &ap->ua_null_walk;
327 328 wp->uaw_prev = prev = next->uaw_prev;
328 329 next->uaw_prev = wp;
329 330 prev->uaw_next = wp;
330 331 }
331 332 }
332 333
333 334 static void *
334 335 _avl_walk_advance(uu_avl_walk_t *wp, uu_avl_t *ap)
335 336 {
336 337 void *np = wp->uaw_next_result;
337 338
338 339 avl_tree_t *t = &ap->ua_tree;
339 340
340 341 if (np == NULL)
341 342 return (NULL);
342 343
343 344 wp->uaw_next_result = (wp->uaw_dir > 0)? AVL_NEXT(t, np) :
344 345 AVL_PREV(t, np);
345 346
346 347 return (np);
347 348 }
348 349
349 350 static void
350 351 _avl_walk_fini(uu_avl_walk_t *wp)
351 352 {
352 353 if (wp->uaw_next != NULL) {
353 354 wp->uaw_next->uaw_prev = wp->uaw_prev;
354 355 wp->uaw_prev->uaw_next = wp->uaw_next;
355 356 wp->uaw_next = NULL;
356 357 wp->uaw_prev = NULL;
357 358 }
358 359 wp->uaw_avl = NULL;
359 360 wp->uaw_next_result = NULL;
360 361 }
361 362
362 363 uu_avl_walk_t *
363 364 uu_avl_walk_start(uu_avl_t *ap, uint32_t flags)
364 365 {
365 366 uu_avl_walk_t *wp;
366 367
367 368 if (flags & ~(UU_WALK_ROBUST | UU_WALK_REVERSE)) {
368 369 uu_set_error(UU_ERROR_UNKNOWN_FLAG);
369 370 return (NULL);
370 371 }
371 372
372 373 wp = uu_zalloc(sizeof (*wp));
373 374 if (wp == NULL) {
374 375 uu_set_error(UU_ERROR_NO_MEMORY);
375 376 return (NULL);
376 377 }
377 378
378 379 _avl_walk_init(wp, ap, flags);
379 380 return (wp);
380 381 }
381 382
382 383 void *
383 384 uu_avl_walk_next(uu_avl_walk_t *wp)
384 385 {
385 386 return (_avl_walk_advance(wp, wp->uaw_avl));
386 387 }
387 388
388 389 void
389 390 uu_avl_walk_end(uu_avl_walk_t *wp)
390 391 {
391 392 _avl_walk_fini(wp);
392 393 uu_free(wp);
393 394 }
394 395
395 396 int
396 397 uu_avl_walk(uu_avl_t *ap, uu_walk_fn_t *func, void *private, uint32_t flags)
397 398 {
398 399 void *e;
399 400 uu_avl_walk_t my_walk;
400 401
401 402 int status = UU_WALK_NEXT;
402 403
403 404 if (flags & ~(UU_WALK_ROBUST | UU_WALK_REVERSE)) {
404 405 uu_set_error(UU_ERROR_UNKNOWN_FLAG);
405 406 return (-1);
406 407 }
407 408
408 409 _avl_walk_init(&my_walk, ap, flags);
409 410 while (status == UU_WALK_NEXT &&
410 411 (e = _avl_walk_advance(&my_walk, ap)) != NULL)
411 412 status = (*func)(e, private);
412 413 _avl_walk_fini(&my_walk);
413 414
414 415 if (status >= 0)
415 416 return (0);
416 417 uu_set_error(UU_ERROR_CALLBACK_FAILED);
417 418 return (-1);
418 419 }
419 420
420 421 void
421 422 uu_avl_remove(uu_avl_t *ap, void *elem)
422 423 {
423 424 uu_avl_walk_t *wp;
424 425 uu_avl_pool_t *pp = ap->ua_pool;
425 426 uintptr_t *na = NODE_ARRAY(pp, elem);
426 427
427 428 if (ap->ua_debug) {
428 429 /*
429 430 * invalidate outstanding uu_avl_index_ts.
430 431 */
431 432 ap->ua_index = INDEX_NEXT(ap->ua_index);
432 433 }
433 434
434 435 /*
435 436 * Robust walkers most be advanced, if we are removing the node
436 437 * they are currently using. In debug mode, non-robust walkers
437 438 * are also on the walker list.
438 439 */
439 440 for (wp = ap->ua_null_walk.uaw_next; wp != &ap->ua_null_walk;
440 441 wp = wp->uaw_next) {
441 442 if (wp->uaw_robust) {
442 443 if (elem == wp->uaw_next_result)
443 444 (void) _avl_walk_advance(wp, ap);
444 445 } else if (wp->uaw_next_result != NULL) {
445 446 uu_panic("uu_avl_remove(%p, %p): active non-robust "
446 447 "walker\n", (void *)ap, elem);
447 448 }
448 449 }
449 450
450 451 avl_remove(&ap->ua_tree, elem);
451 452
452 453 na[0] = POOL_TO_MARKER(pp);
453 454 na[1] = 0;
454 455 }
455 456
456 457 void *
457 458 uu_avl_teardown(uu_avl_t *ap, void **cookie)
458 459 {
459 460 void *elem = avl_destroy_nodes(&ap->ua_tree, cookie);
460 461
461 462 if (elem != NULL) {
462 463 uu_avl_pool_t *pp = ap->ua_pool;
463 464 uintptr_t *na = NODE_ARRAY(pp, elem);
464 465
465 466 na[0] = POOL_TO_MARKER(pp);
466 467 na[1] = 0;
467 468 }
468 469 return (elem);
469 470 }
470 471
471 472 void *
472 473 uu_avl_find(uu_avl_t *ap, void *elem, void *private, uu_avl_index_t *out)
473 474 {
474 475 struct uu_avl_node_compare_info info;
475 476 void *result;
476 477
477 478 info.ac_compare = ap->ua_pool->uap_cmp;
478 479 info.ac_private = private;
479 480 info.ac_right = elem;
480 481 info.ac_found = NULL;
481 482
482 483 result = avl_find(&ap->ua_tree, &info, out);
483 484 if (out != NULL)
484 485 *out = INDEX_ENCODE(ap, *out);
485 486
486 487 if (ap->ua_debug && result != NULL)
487 488 uu_panic("uu_avl_find: internal error: avl_find succeeded\n");
488 489
489 490 return (info.ac_found);
490 491 }
491 492
492 493 void
493 494 uu_avl_insert(uu_avl_t *ap, void *elem, uu_avl_index_t idx)
494 495 {
495 496 if (ap->ua_debug) {
496 497 uu_avl_pool_t *pp = ap->ua_pool;
497 498 uintptr_t *na = NODE_ARRAY(pp, elem);
498 499
499 500 if (na[1] != 0)
500 501 uu_panic("uu_avl_insert(%p, %p, %p): node already "
501 502 "in tree, or corrupt\n",
502 503 (void *)ap, elem, (void *)idx);
503 504 if (na[0] == 0)
504 505 uu_panic("uu_avl_insert(%p, %p, %p): node not "
505 506 "initialized\n",
506 507 (void *)ap, elem, (void *)idx);
507 508 if (na[0] != POOL_TO_MARKER(pp))
508 509 uu_panic("uu_avl_insert(%p, %p, %p): node from "
509 510 "other pool, or corrupt\n",
510 511 (void *)ap, elem, (void *)idx);
511 512
512 513 if (!INDEX_VALID(ap, idx))
513 514 uu_panic("uu_avl_insert(%p, %p, %p): %s\n",
514 515 (void *)ap, elem, (void *)idx,
515 516 INDEX_CHECK(idx)? "outdated index" :
516 517 "invalid index");
517 518
518 519 /*
519 520 * invalidate outstanding uu_avl_index_ts.
520 521 */
521 522 ap->ua_index = INDEX_NEXT(ap->ua_index);
522 523 }
523 524 avl_insert(&ap->ua_tree, elem, INDEX_DECODE(idx));
524 525 }
525 526
526 527 void *
527 528 uu_avl_nearest_next(uu_avl_t *ap, uu_avl_index_t idx)
528 529 {
529 530 if (ap->ua_debug && !INDEX_VALID(ap, idx))
530 531 uu_panic("uu_avl_nearest_next(%p, %p): %s\n",
531 532 (void *)ap, (void *)idx, INDEX_CHECK(idx)?
532 533 "outdated index" : "invalid index");
533 534 return (avl_nearest(&ap->ua_tree, INDEX_DECODE(idx), AVL_AFTER));
534 535 }
535 536
536 537 void *
537 538 uu_avl_nearest_prev(uu_avl_t *ap, uu_avl_index_t idx)
538 539 {
539 540 if (ap->ua_debug && !INDEX_VALID(ap, idx))
540 541 uu_panic("uu_avl_nearest_prev(%p, %p): %s\n",
541 542 (void *)ap, (void *)idx, INDEX_CHECK(idx)?
542 543 "outdated index" : "invalid index");
543 544 return (avl_nearest(&ap->ua_tree, INDEX_DECODE(idx), AVL_BEFORE));
544 545 }
545 546
546 547 /*
547 548 * called from uu_lockup() and uu_release(), as part of our fork1()-safety.
548 549 */
549 550 void
550 551 uu_avl_lockup(void)
551 552 {
552 553 uu_avl_pool_t *pp;
553 554
554 555 (void) pthread_mutex_lock(&uu_apool_list_lock);
555 556 for (pp = uu_null_apool.uap_next; pp != &uu_null_apool;
556 557 pp = pp->uap_next)
557 558 (void) pthread_mutex_lock(&pp->uap_lock);
558 559 }
559 560
560 561 void
561 562 uu_avl_release(void)
562 563 {
563 564 uu_avl_pool_t *pp;
564 565
565 566 for (pp = uu_null_apool.uap_next; pp != &uu_null_apool;
566 567 pp = pp->uap_next)
567 568 (void) pthread_mutex_unlock(&pp->uap_lock);
568 569 (void) pthread_mutex_unlock(&uu_apool_list_lock);
569 570 }
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