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