xref: /freebsd/contrib/ofed/opensm/include/complib/cl_map.h (revision af23369a6deaaeb612ab266eb88b8bb8d560c322)
1 /*
2  * Copyright (c) 2004, 2005 Voltaire, Inc. All rights reserved.
3  * Copyright (c) 2002-2005 Mellanox Technologies LTD. All rights reserved.
4  * Copyright (c) 1996-2003 Intel Corporation. All rights reserved.
5  *
6  * This software is available to you under a choice of one of two
7  * licenses.  You may choose to be licensed under the terms of the GNU
8  * General Public License (GPL) Version 2, available from the file
9  * COPYING in the main directory of this source tree, or the
10  * OpenIB.org BSD license below:
11  *
12  *     Redistribution and use in source and binary forms, with or
13  *     without modification, are permitted provided that the following
14  *     conditions are met:
15  *
16  *      - Redistributions of source code must retain the above
17  *        copyright notice, this list of conditions and the following
18  *        disclaimer.
19  *
20  *      - Redistributions in binary form must reproduce the above
21  *        copyright notice, this list of conditions and the following
22  *        disclaimer in the documentation and/or other materials
23  *        provided with the distribution.
24  *
25  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
26  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
27  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
28  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
29  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
30  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
31  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
32  * SOFTWARE.
33  *
34  */
35 
36 /*
37  * Abstract:
38  *	Declaration of map, a binary tree.
39  */
40 
41 #ifndef _CL_MAP_H_
42 #define _CL_MAP_H_
43 
44 #include <complib/cl_qmap.h>
45 #include <complib/cl_qpool.h>
46 
47 #ifdef __cplusplus
48 #  define BEGIN_C_DECLS extern "C" {
49 #  define END_C_DECLS   }
50 #else				/* !__cplusplus */
51 #  define BEGIN_C_DECLS
52 #  define END_C_DECLS
53 #endif				/* __cplusplus */
54 
55 BEGIN_C_DECLS
56 /****h* Component Library/Map
57 * NAME
58 *	Map
59 *
60 * DESCRIPTION
61 *	Map implements a binary tree that stores user objects.  Each item stored
62 *	in a map has a unique 64-bit key (duplicates are not allowed).  Map
63 *	provides the ability to efficiently search for an item given a key.
64 *
65 *	Map may allocate memory when inserting objects, and can therefore fail
66 *	operations due to insufficient memory.  Use quick map in situations
67 *	where such insertion failures cannot be tolerated.
68 *
69 *	Map is not thread safe, and users must provide serialization when adding
70 *	and removing items from the map.
71 *
72 *	The map functions operates on a cl_map_t structure which should be treated
73 *	as opaque and should be manipulated only through the provided functions.
74 *
75 * SEE ALSO
76 *	Types:
77 *		cl_map_iterator_t
78 *
79 *	Structures:
80 *		cl_map_t, cl_map_item_t, cl_map_obj_t
81 *
82 *	Item Manipulation:
83 *		cl_map_obj, cl_map_key
84 *
85 *	Initialization:
86 *		cl_map_construct, cl_map_init, cl_map_destroy
87 *
88 *	Iteration:
89 *		cl_map_end, cl_map_head, cl_map_tail, cl_map_next, cl_map_prev
90 *
91 *	Manipulation
92 *		cl_map_insert, cl_map_get, cl_map_remove_item, cl_map_remove,
93 *		cl_map_remove_all, cl_map_merge, cl_map_delta, cl_map_get_next
94 *
95 *	Attributes:
96 *		cl_map_count, cl_is_map_empty, cl_is_map_inited
97 *********/
98 /****s* Component Library: Map/cl_map_t
99 * NAME
100 *	cl_map_t
101 *
102 * DESCRIPTION
103 *	Quick map structure.
104 *
105 *	The cl_map_t structure should be treated as opaque and should
106 *	be manipulated only through the provided functions.
107 *
108 * SYNOPSIS
109 */
110 typedef struct _cl_map {
111 	cl_qmap_t qmap;
112 	cl_qpool_t pool;
113 } cl_map_t;
114 /*
115 * FIELDS
116 *	qmap
117 *		Quick map object that maintains the map.
118 *
119 *	pool
120 *		Pool of cl_map_obj_t structures used to store user objects
121 *		in the map.
122 *
123 * SEE ALSO
124 *	Map, cl_map_obj_t
125 *********/
126 
127 /****d* Component Library: Map/cl_map_iterator_t
128 * NAME
129 *	cl_map_iterator_t
130 *
131 * DESCRIPTION
132 *	Iterator type used to walk a map.
133 *
134 * SYNOPSIS
135 */
136 typedef const cl_map_item_t *cl_map_iterator_t;
137 /*
138 * NOTES
139 *	The iterator should be treated as opaque to prevent corrupting the map.
140 *
141 * SEE ALSO
142 *	Map, cl_map_head, cl_map_tail, cl_map_next, cl_map_prev, cl_map_key
143 *********/
144 
145 /****f* Component Library: Map/cl_map_count
146 * NAME
147 *	cl_map_count
148 *
149 * DESCRIPTION
150 *	The cl_map_count function returns the number of items stored
151 *	in a map.
152 *
153 * SYNOPSIS
154 */
155 static inline size_t cl_map_count(IN const cl_map_t * const p_map)
156 {
157 	CL_ASSERT(p_map);
158 	return (cl_qmap_count(&p_map->qmap));
159 }
160 
161 /*
162 * PARAMETERS
163 *	p_map
164 *		[in] Pointer to a map whose item count to return.
165 *
166 * RETURN VALUE
167 *	Returns the number of items stored in the map.
168 *
169 * SEE ALSO
170 *	Map, cl_is_map_empty
171 *********/
172 
173 /****f* Component Library: Map/cl_is_map_empty
174 * NAME
175 *	cl_is_map_empty
176 *
177 * DESCRIPTION
178 *	The cl_is_map_empty function returns whether a map is empty.
179 *
180 * SYNOPSIS
181 */
182 static inline boolean_t cl_is_map_empty(IN const cl_map_t * const p_map)
183 {
184 	CL_ASSERT(p_map);
185 	return (cl_is_qmap_empty(&p_map->qmap));
186 }
187 
188 /*
189 * PARAMETERS
190 *	p_map
191 *		[in] Pointer to a map to test for emptiness.
192 *
193 * RETURN VALUES
194 *	TRUE if the map is empty.
195 *
196 *	FALSE otherwise.
197 *
198 * SEE ALSO
199 *	Map, cl_map_count, cl_map_remove_all
200 *********/
201 
202 /****f* Component Library: Map/cl_map_key
203 * NAME
204 *	cl_map_key
205 *
206 * DESCRIPTION
207 *	The cl_map_key function retrieves the key value of a map item.
208 *
209 * SYNOPSIS
210 */
211 static inline uint64_t cl_map_key(IN const cl_map_iterator_t itor)
212 {
213 	return (cl_qmap_key(itor));
214 }
215 
216 /*
217 * PARAMETERS
218 *	itor
219 *		[in] Iterator for the item whose key to return.
220 *
221 * RETURN VALUE
222 *	Returns the 64-bit key value for the specified iterator.
223 *
224 * NOTES
225 *	The iterator specified by the itor parameter must have been retrived by
226 *	a previous call to cl_map_head, cl_map_tail, cl_map_next, or cl_map_prev.
227 *
228 *	The key value is set in a call to cl_map_insert.
229 *
230 * SEE ALSO
231 *	Map, cl_map_insert, cl_map_head, cl_map_tail, cl_map_next, cl_map_prev
232 *********/
233 
234 /****f* Component Library: Map/cl_map_construct
235 * NAME
236 *	cl_map_construct
237 *
238 * DESCRIPTION
239 *	The cl_map_construct function constructs a map.
240 *
241 * SYNOPSIS
242 */
243 void cl_map_construct(IN cl_map_t * const p_map);
244 /*
245 * PARAMETERS
246 *	p_map
247 *		[in] Pointer to a cl_map_t structure to construct.
248 *
249 * RETURN VALUE
250 *	This function does not return a value.
251 *
252 * NOTES
253 *	Allows calling cl_map_init, cl_map_destroy, and cl_is_map_inited.
254 *
255 *	Calling cl_map_construct is a prerequisite to calling any other
256 *	map function except cl_map_init.
257 *
258 * SEE ALSO
259 *	Map, cl_map_init, cl_map_destroy, cl_is_map_inited
260 *********/
261 
262 /****f* Component Library: Event/cl_is_map_inited
263 * NAME
264 *	cl_is_map_inited
265 *
266 * DESCRIPTION
267 *	The cl_is_map_inited function returns whether a map was
268 *	successfully initialized.
269 *
270 * SYNOPSIS
271 */
272 static inline boolean_t cl_is_map_inited(IN const cl_map_t * const p_map)
273 {
274 	/*
275 	 * The map's pool of map items is the last thing initialized.
276 	 * We can therefore use it to test for initialization.
277 	 */
278 	return (cl_is_qpool_inited(&p_map->pool));
279 }
280 
281 /*
282 * PARAMETERS
283 *	p_map
284 *		[in] Pointer to a cl_map_t structure whose initialization state
285 *		to check.
286 *
287 * RETURN VALUES
288 *	TRUE if the map was initialized successfully.
289 *
290 *	FALSE otherwise.
291 *
292 * NOTES
293 *	Allows checking the state of a map to determine if invoking
294 *	member functions is appropriate.
295 *
296 * SEE ALSO
297 *	Map
298 *********/
299 
300 /****f* Component Library: Map/cl_map_init
301 * NAME
302 *	cl_map_init
303 *
304 * DESCRIPTION
305 *	The cl_map_init function initialized a map for use.
306 *
307 * SYNOPSIS
308 */
309 cl_status_t cl_map_init(IN cl_map_t * const p_map, IN const uint32_t min_items);
310 /*
311 * PARAMETERS
312 *	p_map
313 *		[in] Pointer to a cl_map_t structure to initialize.
314 *
315 *	min_items
316 *		[in] Minimum number of items that can be stored.  All necessary
317 *		allocations to allow storing the minimum number of items is
318 *		performed at initialization time.
319 *
320 * RETURN VALUES
321 *	CL_SUCCESS if the map was initialized successfully.
322 *
323 * NOTES
324 *	Allows calling map manipulation functions.
325 *
326 * SEE ALSO
327 *	Map, cl_map_destroy, cl_map_insert, cl_map_remove
328 *********/
329 
330 /****f* Component Library: Map/cl_map_destroy
331 * NAME
332 *	cl_map_destroy
333 *
334 * DESCRIPTION
335 *	The cl_map_destroy function destroys a map.
336 *
337 * SYNOPSIS
338 */
339 void cl_map_destroy(IN cl_map_t * const p_map);
340 /*
341 * PARAMETERS
342 *	p_map
343 *		[in] Pointer to a map to destroy.
344 *
345 * RETURN VALUE
346 *	This function does not return a value.
347 *
348 * NOTES
349 *	Performs any necessary cleanup of the specified map. Further
350 *	operations should not be attempted on the map. cl_map_destroy does
351 *	not affect any of the objects stored in the map.
352 *	This function should only be called after a call to cl_map_construct.
353 *
354 *	In debug builds, cl_map_destroy asserts that the map is empty.
355 *
356 * SEE ALSO
357 *	Map, cl_map_construct, cl_map_init
358 *********/
359 
360 /****f* Component Library: Map/cl_map_end
361 * NAME
362 *	cl_map_end
363 *
364 * DESCRIPTION
365 *	The cl_map_end function returns the iterator for the end of a map.
366 *
367 * SYNOPSIS
368 */
369 static inline cl_map_iterator_t cl_map_end(IN const cl_map_t * const p_map)
370 {
371 	CL_ASSERT(p_map);
372 	return (cl_qmap_end(&p_map->qmap));
373 }
374 
375 /*
376 * PARAMETERS
377 *	p_map
378 *		[in] Pointer to a cl_map_t structure whose end to return.
379 *
380 * RETURN VALUE
381 *	Iterator for the end of the map.
382 *
383 * NOTES
384 *	cl_map_end is useful for determining the validity of map items returned
385 *	by cl_map_head, cl_map_tail, cl_map_next, cl_map_prev.  If the iterator
386 *	by any of these functions compares to the end, the end of the map was
387 *	encoutered.
388 *	When using cl_map_head or cl_map_tail, this condition indicates that
389 *	the map is empty.
390 *
391 * SEE ALSO
392 *	Map, cl_qmap_head, cl_qmap_tail, cl_qmap_next, cl_qmap_prev
393 *********/
394 
395 /****f* Component Library: Map/cl_map_head
396 * NAME
397 *	cl_map_head
398 *
399 * DESCRIPTION
400 *	The cl_map_head function returns the map item with the lowest key
401 *	value stored in a map.
402 *
403 * SYNOPSIS
404 */
405 static inline cl_map_iterator_t cl_map_head(IN const cl_map_t * const p_map)
406 {
407 	CL_ASSERT(p_map);
408 	return (cl_qmap_head(&p_map->qmap));
409 }
410 
411 /*
412 * PARAMETERS
413 *	p_map
414 *		[in] Pointer to a map whose item with the lowest key is returned.
415 *
416 * RETURN VALUES
417 *	Iterator for the object with the lowest key in the map.
418 *
419 *	Iterator for the map end if the map was empty.
420 *
421 * NOTES
422 *	cl_map_head does not remove the object from the map.
423 *
424 * SEE ALSO
425 *	Map, cl_map_tail, cl_map_next, cl_map_prev, cl_map_end
426 *********/
427 
428 /****f* Component Library: Map/cl_map_tail
429 * NAME
430 *	cl_map_tail
431 *
432 * DESCRIPTION
433 *	The cl_map_tail function returns the map item with the highest key
434 *	value stored in a map.
435 *
436 * SYNOPSIS
437 */
438 static inline cl_map_iterator_t cl_map_tail(IN const cl_map_t * const p_map)
439 {
440 	CL_ASSERT(p_map);
441 	return (cl_qmap_tail(&p_map->qmap));
442 }
443 
444 /*
445 * PARAMETERS
446 *	p_map
447 *		[in] Pointer to a map whose item with the highest key
448 *		is returned.
449 *
450 * RETURN VALUES
451 *	Iterator for the object with the highest key in the map.
452 *
453 *	Iterator for the map end if the map was empty.
454 *
455 * NOTES
456 *	cl_map_end does no remove the object from the map.
457 *
458 * SEE ALSO
459 *	Map, cl_map_head, cl_map_next, cl_map_prev, cl_map_end
460 *********/
461 
462 /****f* Component Library: Map/cl_map_next
463 * NAME
464 *	cl_map_next
465 *
466 * DESCRIPTION
467 *	The cl_map_next function returns the map item with the next higher
468 *	key value than a specified map item.
469 *
470 * SYNOPSIS
471 */
472 static inline cl_map_iterator_t cl_map_next(IN const cl_map_iterator_t itor)
473 {
474 	CL_ASSERT(itor);
475 	return (cl_qmap_next(itor));
476 }
477 
478 /*
479 * PARAMETERS
480 *	itor
481 *		[in] Iterator for an object in a map whose successor to return.
482 *
483 * RETURN VALUES
484 *	Iterator for the object with the next higher key value in a map.
485 *
486 *	Iterator for the map end if the specified object was the last item in
487 *	the map.
488 *
489 * NOTES
490 *	The iterator must have been retrieved by a previous call to cl_map_head,
491 *	cl_map_tail, cl_map_next, or cl_map_prev.
492 *
493 * SEE ALSO
494 *	Map, cl_map_head, cl_map_tail, cl_map_prev, cl_map_end
495 *********/
496 
497 /****f* Component Library: Map/cl_map_prev
498 * NAME
499 *	cl_map_prev
500 *
501 * DESCRIPTION
502 *	The cl_map_prev function returns the map item with the next lower
503 *	key value than a precified map item.
504 *
505 * SYNOPSIS
506 */
507 static inline cl_map_iterator_t cl_map_prev(IN const cl_map_iterator_t itor)
508 {
509 	CL_ASSERT(itor);
510 	return (cl_qmap_prev(itor));
511 }
512 
513 /*
514 * PARAMETERS
515 *	itor
516 *		[in] Iterator for an object in a map whose predecessor to return.
517 *
518 * RETURN VALUES
519 *	Iterator for the object with the next lower key value in a map.
520 *
521 *	Iterator for the map end if the specified object was the first item in
522 *	the map.
523 *
524 * NOTES
525 *	The iterator must have been retrieved by a previous call to cl_map_head,
526 *	cl_map_tail, cl_map_next, or cl_map_prev.
527 *
528 * SEE ALSO
529 *	Map, cl_map_head, cl_map_tail, cl_map_next, cl_map_end
530 *********/
531 
532 /****f* Component Library: Map/cl_map_insert
533 * NAME
534 *	cl_map_insert
535 *
536 * DESCRIPTION
537 *	The cl_map_insert function inserts a map item into a map.
538 *
539 * SYNOPSIS
540 */
541 void *cl_map_insert(IN cl_map_t * const p_map,
542 		    IN const uint64_t key, IN const void *const p_object);
543 /*
544 * PARAMETERS
545 *	p_map
546 *		[in] Pointer to a map into which to add the item.
547 *
548 *	key
549 *		[in] Value to associate with the object.
550 *
551 *	p_object
552 *		[in] Pointer to an object to insert into the map.
553 *
554 * RETURN VALUES
555 *	Pointer to the object in the map with the specified key after the call
556 *	completes.
557 *
558 *	NULL if there was not enough memory to insert the desired item.
559 *
560 * NOTES
561 *	Insertion operations may cause the map to rebalance.
562 *
563 *	If the map already contains an object already with the specified key,
564 *	that object will not be replaced and the pointer to that object is
565 *	returned.
566 *
567 * SEE ALSO
568 *	Map, cl_map_remove, cl_map_item_t
569 *********/
570 
571 /****f* Component Library: Map/cl_map_get
572 * NAME
573 *	cl_map_get
574 *
575 * DESCRIPTION
576 *	The cl_map_get function returns the object associated with a key.
577 *
578 * SYNOPSIS
579 */
580 void *cl_map_get(IN const cl_map_t * const p_map, IN const uint64_t key);
581 /*
582 * PARAMETERS
583 *	p_map
584 *		[in] Pointer to a map from which to retrieve the object with
585 *		the specified key.
586 *
587 *	key
588 *		[in] Key value used to search for the desired object.
589 *
590 * RETURN VALUES
591 *	Pointer to the object with the desired key value.
592 *
593 *	NULL if there was no item with the desired key value stored in
594 *	the map.
595 *
596 * NOTES
597 *	cl_map_get does not remove the item from the map.
598 *
599 * SEE ALSO
600 *	Map, cl_map_remove, cl_map_get_next
601 *********/
602 
603 /****f* Component Library: Map/cl_map_get_next
604 * NAME
605 *	cl_map_get_next
606 *
607 * DESCRIPTION
608 *	The cl_qmap_get_next function returns the first object associated with a
609 *	key > the key specified.
610 *
611 * SYNOPSIS
612 */
613 void *cl_map_get_next(IN const cl_map_t * const p_map, IN const uint64_t key);
614 /*
615 * PARAMETERS
616 *	p_map
617 *		[in] Pointer to a map from which to retrieve the object with
618 *		the specified key.
619 *
620 *	key
621 *		[in] Key value used to search for the desired object.
622 *
623 * RETURN VALUES
624 *	Pointer to the first object with a key > the desired key value.
625 *
626 *	NULL if there was no item with a key > the desired key
627 *	value stored in the map.
628 *
629 * NOTES
630 *	cl_map_get does not remove the item from the map.
631 *
632 * SEE ALSO
633 *	Map, cl_map_remove, cl_map_get
634 *********/
635 
636 /****f* Component Library: Map/cl_map_remove_item
637 * NAME
638 *	cl_map_remove_item
639 *
640 * DESCRIPTION
641 *	The cl_map_remove_item function removes the specified map item
642 *	from a map.
643 *
644 * SYNOPSIS
645 */
646 void
647 cl_map_remove_item(IN cl_map_t * const p_map, IN const cl_map_iterator_t itor);
648 /*
649 * PARAMETERS
650 *	p_map
651 *		[in] Pointer to a map from which to remove the object associated
652 *		with the specified iterator.
653 *
654 *	itor
655 *		[in] Iterator for an object to remove from its map.
656 *
657 * RETURN VALUE
658 *	This function does not return a value.
659 *
660 * NOTES
661 *	Removes the object associated with the specifid iterator from its map.
662 *
663 *	The specified iterator is no longer valid after the call completes.
664 *
665 *	The iterator must have been retrieved by a previous call to cl_map_head,
666 *	cl_map_tail, cl_map_next, or cl_map_prev.
667 *
668 * SEE ALSO
669 *	Map, cl_map_remove, cl_map_remove_all, cl_map_insert, cl_map_head,
670 *	cl_map_tail, cl_map_next, cl_map_prev
671 *********/
672 
673 /****f* Component Library: Map/cl_map_remove
674 * NAME
675 *	cl_map_remove
676 *
677 * DESCRIPTION
678 *	The cl_map_remove function removes the map item with the specified key
679 *	from a map.
680 *
681 * SYNOPSIS
682 */
683 void *cl_map_remove(IN cl_map_t * const p_map, IN const uint64_t key);
684 /*
685 * PARAMETERS
686 *	p_map
687 *		[in] Pointer to a cl_map_t structure from which to remove the
688 *		item with the specified key.
689 *
690 *	key
691 *		[in] Key value used to search for the object to remove.
692 *
693 * RETURN VALUES
694 *	Pointer to the object associated with the specified key if
695 *	it was found and removed.
696 *
697 *	NULL if no object with the specified key exists in the map.
698 *
699 * SEE ALSO
700 *	Map, cl_map_remove_item, cl_map_remove_all, cl_map_insert
701 *********/
702 
703 /****f* Component Library: Map/cl_map_remove_all
704 * NAME
705 *	cl_map_remove_all
706 *
707 * DESCRIPTION
708 *	The cl_map_remove_all function removes all objects from a map,
709 *	leaving it empty.
710 *
711 * SYNOPSIS
712 */
713 void cl_map_remove_all(IN cl_map_t * const p_map);
714 /*
715 * PARAMETERS
716 *	p_map
717 *		[in] Pointer to a map to empty.
718 *
719 * RETURN VALUE
720 *	This function does not return a value.
721 *
722 * SEE ALSO
723 *	Map, cl_map_remove, cl_map_remove_item
724 *********/
725 
726 /****f* Component Library: Map/cl_map_obj
727 * NAME
728 *	cl_map_obj
729 *
730 * DESCRIPTION
731 *	The cl_map_obj function returns the object associated with an iterator.
732 *
733 * SYNOPSIS
734 */
735 static inline void *cl_map_obj(IN const cl_map_iterator_t itor)
736 {
737 	return (cl_qmap_obj(PARENT_STRUCT(itor, cl_map_obj_t, item)));
738 }
739 
740 /*
741 * PARAMETERS
742 *	itor
743 *		[in] Iterator whose object to return.
744 *
745 * RETURN VALUES
746 *	Returns the value of the object pointer associated with the iterator.
747 *
748 *	The iterator must have been retrieved by a previous call to cl_map_head,
749 *	cl_map_tail, cl_map_next, or cl_map_prev.
750 *
751 * SEE ALSO
752 *	Map, cl_map_head, cl_map_tail, cl_map_next, cl_map_prev
753 *********/
754 
755 /****f* Component Library: Map/cl_map_merge
756 * NAME
757 *	cl_map_merge
758 *
759 * DESCRIPTION
760 *	The cl_map_merge function moves all items from one map to another,
761 *	excluding duplicates.
762 *
763 * SYNOPSIS
764 */
765 cl_status_t
766 cl_map_merge(OUT cl_map_t * const p_dest_map,
767 	     IN OUT cl_map_t * const p_src_map);
768 /*
769 * PARAMETERS
770 *	p_dest_map
771 *		[out] Pointer to a cl_map_t structure to which items should be added.
772 *
773 *	p_src_map
774 *		[in/out] Pointer to a cl_map_t structure whose items to add
775 *		to p_dest_map.
776 *
777 * RETURN VALUES
778 *	CL_SUCCESS if the operation succeeded.
779 *
780 *	CL_INSUFFICIENT_MEMORY if there was not enough memory for the operation
781 *	to succeed.
782 *
783 * NOTES
784 *	Items are evaluated based on their keys only.
785 *
786 *	Upon return from cl_map_merge, the map referenced by p_src_map contains
787 *	all duplicate items.
788 *
789 * SEE ALSO
790 *	Map, cl_map_delta
791 *********/
792 
793 /****f* Component Library: Map/cl_map_delta
794 * NAME
795 *	cl_map_delta
796 *
797 * DESCRIPTION
798 *	The cl_map_delta function computes the differences between two maps.
799 *
800 * SYNOPSIS
801 */
802 cl_status_t
803 cl_map_delta(IN OUT cl_map_t * const p_map1,
804 	     IN OUT cl_map_t * const p_map2,
805 	     OUT cl_map_t * const p_new, OUT cl_map_t * const p_old);
806 /*
807 * PARAMETERS
808 *	p_map1
809 *		[in/out] Pointer to the first of two cl_map_t structures whose
810 *		differences to compute.
811 *
812 *	p_map2
813 *		[in/out] Pointer to the second of two cl_map_t structures whose
814 *		differences to compute.
815 *
816 *	p_new
817 *		[out] Pointer to an empty cl_map_t structure that contains the
818 *		items unique to p_map2 upon return from the function.
819 *
820 *	p_old
821 *		[out] Pointer to an empty cl_map_t structure that contains the
822 *		items unique to p_map1 upon return from the function.
823 *
824 * RETURN VALUES
825 *	CL_SUCCESS if the operation succeeded.
826 *
827 *	CL_INSUFFICIENT_MEMORY if there was not enough memory for the operation
828 *	to succeed.
829 *
830 * NOTES
831 *	Items are evaluated based on their keys.  Items that exist in both
832 *	p_map1 and p_map2 remain in their respective maps.  Items that
833 *	exist only p_map1 are moved to p_old.  Likewise, items that exist only
834 *	in p_map2 are moved to p_new.  This function can be useful in evaluating
835 *	changes between two maps.
836 *
837 *	Both maps pointed to by p_new and p_old must be empty on input.
838 *
839 *	Upon failure, all input maps are restored to their original state.
840 *
841 * SEE ALSO
842 *	Map, cl_map_merge
843 *********/
844 
845 END_C_DECLS
846 #endif				/* _CL_MAP_H_ */
847