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