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diff --git a/src/util/container_bloomfilter.c b/src/util/container_bloomfilter.c
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1/*
2 This file is part of GNUnet.
3 Copyright (C) 2001, 2002, 2003, 2004, 2006, 2008, 2011, 2012, 2018 GNUnet e.V.
4
5 GNUnet is free software: you can redistribute it and/or modify it
6 under the terms of the GNU Affero General Public License as published
7 by the Free Software Foundation, either version 3 of the License,
8 or (at your option) any later version.
9
10 GNUnet is distributed in the hope that it will be useful, but
11 WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Affero General Public License for more details.
14
15 You should have received a copy of the GNU Affero General Public License
16 along with this program. If not, see <http://www.gnu.org/licenses/>.
17
18 SPDX-License-Identifier: AGPL3.0-or-later
19 */
20/**
21 * @file util/container_bloomfilter.c
22 * @brief data structure used to reduce disk accesses.
23 *
24 * The idea basically: Create a signature for each element in the
25 * database. Add those signatures to a bit array. When doing a lookup,
26 * check if the bit array matches the signature of the requested
27 * element. If yes, address the disk, otherwise return 'not found'.
28 *
29 * A property of the bloom filter is that sometimes we will have
30 * a match even if the element is not on the disk (then we do
31 * an unnecessary disk access), but what's most important is that
32 * we never get a single "false negative".
33 *
34 * To be able to delete entries from the bloom filter, we maintain
35 * a 4 bit counter in the file on the drive (we still use only one
36 * bit in memory).
37 *
38 * @author Igor Wronsky
39 * @author Christian Grothoff
40 */
41
42#include "platform.h"
43#include "gnunet_util_lib.h"
44
45#define LOG(kind, ...) \
46 GNUNET_log_from (kind, "util-container-bloomfilter", __VA_ARGS__)
47
48#define LOG_STRERROR(kind, syscall) \
49 GNUNET_log_from_strerror (kind, "util-container-bloomfilter", syscall)
50
51#define LOG_STRERROR_FILE(kind, syscall, filename) \
52 GNUNET_log_from_strerror_file (kind, \
53 "util-container-bloomfilter", \
54 syscall, \
55 filename)
56
57struct GNUNET_CONTAINER_BloomFilter
58{
59 /**
60 * The actual bloomfilter bit array
61 */
62 char *bitArray;
63
64 /**
65 * Filename of the filter
66 */
67 char *filename;
68
69 /**
70 * The bit counter file on disk
71 */
72 struct GNUNET_DISK_FileHandle *fh;
73
74 /**
75 * How many bits we set for each stored element
76 */
77 unsigned int addressesPerElement;
78
79 /**
80 * Size of bitArray in bytes
81 */
82 size_t bitArraySize;
83};
84
85
86/**
87 * Get the number of the addresses set per element in the bloom filter.
88 *
89 * @param bf the filter
90 * @return addresses set per element in the bf
91 */
92size_t
93GNUNET_CONTAINER_bloomfilter_get_element_addresses (
94 const struct GNUNET_CONTAINER_BloomFilter *bf)
95{
96 if (bf == NULL)
97 return 0;
98 return bf->addressesPerElement;
99}
100
101
102/**
103 * Get size of the bloom filter.
104 *
105 * @param bf the filter
106 * @return number of bytes used for the data of the bloom filter
107 */
108size_t
109GNUNET_CONTAINER_bloomfilter_get_size (
110 const struct GNUNET_CONTAINER_BloomFilter *bf)
111{
112 if (bf == NULL)
113 return 0;
114 return bf->bitArraySize;
115}
116
117
118/**
119 * Copy an existing memory. Any association with a file
120 * on-disk will be lost in the process.
121 * @param bf the filter to copy
122 * @return copy of the bf
123 */
124struct GNUNET_CONTAINER_BloomFilter *
125GNUNET_CONTAINER_bloomfilter_copy (
126 const struct GNUNET_CONTAINER_BloomFilter *bf)
127{
128 return GNUNET_CONTAINER_bloomfilter_init (bf->bitArray,
129 bf->bitArraySize,
130 bf->addressesPerElement);
131}
132
133
134/**
135 * Sets a bit active in the bitArray. Increment bit-specific
136 * usage counter on disk only if below 4bit max (==15).
137 *
138 * @param bitArray memory area to set the bit in
139 * @param bitIdx which bit to set
140 */
141static void
142setBit (char *bitArray, unsigned int bitIdx)
143{
144 size_t arraySlot;
145 unsigned int targetBit;
146
147 arraySlot = bitIdx / 8;
148 targetBit = (1L << (bitIdx % 8));
149 bitArray[arraySlot] |= targetBit;
150}
151
152
153/**
154 * Clears a bit from bitArray. Bit is cleared from the array
155 * only if the respective usage counter on the disk hits/is zero.
156 *
157 * @param bitArray memory area to set the bit in
158 * @param bitIdx which bit to unset
159 */
160static void
161clearBit (char *bitArray, unsigned int bitIdx)
162{
163 size_t slot;
164 unsigned int targetBit;
165
166 slot = bitIdx / 8;
167 targetBit = (1L << (bitIdx % 8));
168 bitArray[slot] = bitArray[slot] & (~targetBit);
169}
170
171
172/**
173 * Checks if a bit is active in the bitArray
174 *
175 * @param bitArray memory area to set the bit in
176 * @param bitIdx which bit to test
177 * @return GNUNET_YES if the bit is set, GNUNET_NO if not.
178 */
179static int
180testBit (char *bitArray, unsigned int bitIdx)
181{
182 size_t slot;
183 unsigned int targetBit;
184
185 slot = bitIdx / 8;
186 targetBit = (1L << (bitIdx % 8));
187 if (bitArray[slot] & targetBit)
188 return GNUNET_YES;
189 else
190 return GNUNET_NO;
191}
192
193
194/**
195 * Sets a bit active in the bitArray and increments
196 * bit-specific usage counter on disk (but only if
197 * the counter was below 4 bit max (==15)).
198 *
199 * @param bitArray memory area to set the bit in
200 * @param bitIdx which bit to test
201 * @param fh A file to keep the 4 bit address usage counters in
202 */
203static void
204incrementBit (char *bitArray,
205 unsigned int bitIdx,
206 const struct GNUNET_DISK_FileHandle *fh)
207{
208 off_t fileSlot;
209 unsigned char value;
210 unsigned int high;
211 unsigned int low;
212 unsigned int targetLoc;
213
214 setBit (bitArray, bitIdx);
215 if (GNUNET_DISK_handle_invalid (fh))
216 return;
217 /* Update the counter file on disk */
218 fileSlot = bitIdx / 2;
219 targetLoc = bitIdx % 2;
220
221 GNUNET_assert (fileSlot ==
222 GNUNET_DISK_file_seek (fh, fileSlot, GNUNET_DISK_SEEK_SET));
223 if (1 != GNUNET_DISK_file_read (fh, &value, 1))
224 value = 0;
225 low = value & 0xF;
226 high = (value & (~0xF)) >> 4;
227
228 if (targetLoc == 0)
229 {
230 if (low < 0xF)
231 low++;
232 }
233 else
234 {
235 if (high < 0xF)
236 high++;
237 }
238 value = ((high << 4) | low);
239 GNUNET_assert (fileSlot ==
240 GNUNET_DISK_file_seek (fh, fileSlot, GNUNET_DISK_SEEK_SET));
241 GNUNET_assert (1 == GNUNET_DISK_file_write (fh, &value, 1));
242}
243
244
245/**
246 * Clears a bit from bitArray if the respective usage
247 * counter on the disk hits/is zero.
248 *
249 * @param bitArray memory area to set the bit in
250 * @param bitIdx which bit to test
251 * @param fh A file to keep the 4bit address usage counters in
252 */
253static void
254decrementBit (char *bitArray,
255 unsigned int bitIdx,
256 const struct GNUNET_DISK_FileHandle *fh)
257{
258 off_t fileslot;
259 unsigned char value;
260 unsigned int high;
261 unsigned int low;
262 unsigned int targetLoc;
263
264 if (GNUNET_DISK_handle_invalid (fh))
265 return; /* cannot decrement! */
266 /* Each char slot in the counter file holds two 4 bit counters */
267 fileslot = bitIdx / 2;
268 targetLoc = bitIdx % 2;
269 if (GNUNET_SYSERR ==
270 GNUNET_DISK_file_seek (fh, fileslot, GNUNET_DISK_SEEK_SET))
271 {
272 GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR, "seek");
273 return;
274 }
275 if (1 != GNUNET_DISK_file_read (fh, &value, 1))
276 value = 0;
277 low = value & 0xF;
278 high = (value & 0xF0) >> 4;
279
280 /* decrement, but once we have reached the max, never go back! */
281 if (targetLoc == 0)
282 {
283 if ((low > 0) && (low < 0xF))
284 low--;
285 if (low == 0)
286 {
287 clearBit (bitArray, bitIdx);
288 }
289 }
290 else
291 {
292 if ((high > 0) && (high < 0xF))
293 high--;
294 if (high == 0)
295 {
296 clearBit (bitArray, bitIdx);
297 }
298 }
299 value = ((high << 4) | low);
300 if (GNUNET_SYSERR ==
301 GNUNET_DISK_file_seek (fh, fileslot, GNUNET_DISK_SEEK_SET))
302 {
303 GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR, "seek");
304 return;
305 }
306 GNUNET_assert (1 == GNUNET_DISK_file_write (fh, &value, 1));
307}
308
309
310#define BUFFSIZE 65536
311
312/**
313 * Creates a file filled with zeroes
314 *
315 * @param fh the file handle
316 * @param size the size of the file
317 * @return GNUNET_OK if created ok, GNUNET_SYSERR otherwise
318 */
319static int
320make_empty_file (const struct GNUNET_DISK_FileHandle *fh, size_t size)
321{
322 char buffer[BUFFSIZE];
323 size_t bytesleft = size;
324 int res = 0;
325
326 if (GNUNET_DISK_handle_invalid (fh))
327 return GNUNET_SYSERR;
328 memset (buffer, 0, sizeof(buffer));
329 GNUNET_DISK_file_seek (fh, 0, GNUNET_DISK_SEEK_SET);
330 while (bytesleft > 0)
331 {
332 if (bytesleft > sizeof(buffer))
333 {
334 res = GNUNET_DISK_file_write (fh, buffer, sizeof(buffer));
335 if (res >= 0)
336 bytesleft -= res;
337 }
338 else
339 {
340 res = GNUNET_DISK_file_write (fh, buffer, bytesleft);
341 if (res >= 0)
342 bytesleft -= res;
343 }
344 if (GNUNET_SYSERR == res)
345 return GNUNET_SYSERR;
346 }
347 return GNUNET_OK;
348}
349
350
351/* ************** GNUNET_CONTAINER_BloomFilter iterator ********* */
352
353/**
354 * Iterator (callback) method to be called by the
355 * bloomfilter iterator on each bit that is to be
356 * set or tested for the key.
357 *
358 * @param cls closure
359 * @param bf the filter to manipulate
360 * @param bit the current bit
361 * @return GNUNET_YES to continue, GNUNET_NO to stop early
362 */
363typedef int (*BitIterator) (void *cls,
364 const struct GNUNET_CONTAINER_BloomFilter *bf,
365 unsigned int bit);
366
367
368/**
369 * Call an iterator for each bit that the bloomfilter
370 * must test or set for this element.
371 *
372 * @param bf the filter
373 * @param callback the method to call
374 * @param arg extra argument to callback
375 * @param key the key for which we iterate over the BF bits
376 */
377static void
378iterateBits (const struct GNUNET_CONTAINER_BloomFilter *bf,
379 BitIterator callback,
380 void *arg,
381 const struct GNUNET_HashCode *key)
382{
383 struct GNUNET_HashCode tmp[2];
384 int bitCount;
385 unsigned int round;
386 unsigned int slot = 0;
387
388 bitCount = bf->addressesPerElement;
389 tmp[0] = *key;
390 round = 0;
391 GNUNET_assert (bf->bitArraySize > 0);
392 GNUNET_assert (bf->bitArraySize * 8LL > bf->bitArraySize);
393 while (bitCount > 0)
394 {
395 while (slot < (sizeof(struct GNUNET_HashCode) / sizeof(uint32_t)))
396 {
397 if (GNUNET_YES !=
398 callback (arg,
399 bf,
400 ntohl ((((uint32_t *) &tmp[round & 1])[slot]))
401 % ((bf->bitArraySize * 8LL))))
402 return;
403 slot++;
404 bitCount--;
405 if (bitCount == 0)
406 break;
407 }
408 if (bitCount > 0)
409 {
410 GNUNET_CRYPTO_hash (&tmp[round & 1],
411 sizeof(struct GNUNET_HashCode),
412 &tmp[(round + 1) & 1]);
413 round++;
414 slot = 0;
415 }
416 }
417}
418
419
420/**
421 * Callback: increment bit
422 *
423 * @param cls pointer to writeable form of bf
424 * @param bf the filter to manipulate
425 * @param bit the bit to increment
426 * @return GNUNET_YES
427 */
428static int
429incrementBitCallback (void *cls,
430 const struct GNUNET_CONTAINER_BloomFilter *bf,
431 unsigned int bit)
432{
433 struct GNUNET_CONTAINER_BloomFilter *b = cls;
434
435 incrementBit (b->bitArray, bit, bf->fh);
436 return GNUNET_YES;
437}
438
439
440/**
441 * Callback: decrement bit
442 *
443 * @param cls pointer to writeable form of bf
444 * @param bf the filter to manipulate
445 * @param bit the bit to decrement
446 * @return GNUNET_YES
447 */
448static int
449decrementBitCallback (void *cls,
450 const struct GNUNET_CONTAINER_BloomFilter *bf,
451 unsigned int bit)
452{
453 struct GNUNET_CONTAINER_BloomFilter *b = cls;
454
455 decrementBit (b->bitArray, bit, bf->fh);
456 return GNUNET_YES;
457}
458
459
460/**
461 * Callback: test if all bits are set
462 *
463 * @param cls pointer set to GNUNET_NO if bit is not set
464 * @param bf the filter
465 * @param bit the bit to test
466 * @return YES if the bit is set, NO if not
467 */
468static int
469testBitCallback (void *cls,
470 const struct GNUNET_CONTAINER_BloomFilter *bf,
471 unsigned int bit)
472{
473 int *arg = cls;
474
475 if (GNUNET_NO == testBit (bf->bitArray, bit))
476 {
477 *arg = GNUNET_NO;
478 return GNUNET_NO;
479 }
480 return GNUNET_YES;
481}
482
483
484/* *********************** INTERFACE **************** */
485
486/**
487 * Load a bloom-filter from a file.
488 *
489 * @param filename the name of the file (or the prefix)
490 * @param size the size of the bloom-filter (number of
491 * bytes of storage space to use); will be rounded up
492 * to next power of 2
493 * @param k the number of GNUNET_CRYPTO_hash-functions to apply per
494 * element (number of bits set per element in the set)
495 * @return the bloomfilter
496 */
497struct GNUNET_CONTAINER_BloomFilter *
498GNUNET_CONTAINER_bloomfilter_load (const char *filename,
499 size_t size,
500 unsigned int k)
501{
502 struct GNUNET_CONTAINER_BloomFilter *bf;
503 char *rbuff;
504 off_t pos;
505 int i;
506 size_t ui;
507 off_t fsize;
508 int must_read;
509
510 GNUNET_assert (NULL != filename);
511 if ((k == 0) || (size == 0))
512 return NULL;
513 if (size < BUFFSIZE)
514 size = BUFFSIZE;
515 ui = 1;
516 while ((ui < size) && (ui * 2 > ui))
517 ui *= 2;
518 size = ui; /* make sure it's a power of 2 */
519
520 bf = GNUNET_new (struct GNUNET_CONTAINER_BloomFilter);
521 /* Try to open a bloomfilter file */
522 if (GNUNET_YES == GNUNET_DISK_file_test (filename))
523 bf->fh = GNUNET_DISK_file_open (filename,
524 GNUNET_DISK_OPEN_READWRITE,
525 GNUNET_DISK_PERM_USER_READ
526 | GNUNET_DISK_PERM_USER_WRITE);
527 if (NULL != bf->fh)
528 {
529 /* file existed, try to read it! */
530 must_read = GNUNET_YES;
531 if (GNUNET_OK != GNUNET_DISK_file_handle_size (bf->fh, &fsize))
532 {
533 GNUNET_DISK_file_close (bf->fh);
534 GNUNET_free (bf);
535 return NULL;
536 }
537 if (0 == fsize)
538 {
539 /* found existing empty file, just overwrite */
540 if (GNUNET_OK != make_empty_file (bf->fh, size * 4LL))
541 {
542 GNUNET_log_strerror (GNUNET_ERROR_TYPE_WARNING, "write");
543 GNUNET_DISK_file_close (bf->fh);
544 GNUNET_free (bf);
545 return NULL;
546 }
547 }
548 else if (fsize != ((off_t) size) * 4LL)
549 {
550 GNUNET_log (
551 GNUNET_ERROR_TYPE_ERROR,
552 _ (
553 "Size of file on disk is incorrect for this Bloom filter (want %llu, have %llu)\n"),
554 (unsigned long long) (size * 4LL),
555 (unsigned long long) fsize);
556 GNUNET_DISK_file_close (bf->fh);
557 GNUNET_free (bf);
558 return NULL;
559 }
560 }
561 else
562 {
563 /* file did not exist, don't read, just create */
564 must_read = GNUNET_NO;
565 bf->fh = GNUNET_DISK_file_open (filename,
566 GNUNET_DISK_OPEN_CREATE
567 | GNUNET_DISK_OPEN_READWRITE,
568 GNUNET_DISK_PERM_USER_READ
569 | GNUNET_DISK_PERM_USER_WRITE);
570 if (NULL == bf->fh)
571 {
572 GNUNET_free (bf);
573 return NULL;
574 }
575 if (GNUNET_OK != make_empty_file (bf->fh, size * 4LL))
576 {
577 GNUNET_log_strerror (GNUNET_ERROR_TYPE_WARNING, "write");
578 GNUNET_DISK_file_close (bf->fh);
579 GNUNET_free (bf);
580 return NULL;
581 }
582 }
583 bf->filename = GNUNET_strdup (filename);
584 /* Alloc block */
585 bf->bitArray = GNUNET_malloc_large (size);
586 if (NULL == bf->bitArray)
587 {
588 if (NULL != bf->fh)
589 GNUNET_DISK_file_close (bf->fh);
590 GNUNET_free (bf->filename);
591 GNUNET_free (bf);
592 return NULL;
593 }
594 bf->bitArraySize = size;
595 bf->addressesPerElement = k;
596 if (GNUNET_YES != must_read)
597 return bf; /* already done! */
598 /* Read from the file what bits we can */
599 rbuff = GNUNET_malloc (BUFFSIZE);
600 pos = 0;
601 while (pos < ((off_t) size) * 8LL)
602 {
603 int res;
604
605 res = GNUNET_DISK_file_read (bf->fh, rbuff, BUFFSIZE);
606 if (res == -1)
607 {
608 LOG_STRERROR_FILE (GNUNET_ERROR_TYPE_WARNING, "read", bf->filename);
609 GNUNET_free (rbuff);
610 GNUNET_free (bf->filename);
611 GNUNET_DISK_file_close (bf->fh);
612 GNUNET_free (bf);
613 return NULL;
614 }
615 if (res == 0)
616 break; /* is ok! we just did not use that many bits yet */
617 for (i = 0; i < res; i++)
618 {
619 if ((rbuff[i] & 0x0F) != 0)
620 setBit (bf->bitArray, pos + i * 2);
621 if ((rbuff[i] & 0xF0) != 0)
622 setBit (bf->bitArray, pos + i * 2 + 1);
623 }
624 if (res < BUFFSIZE)
625 break;
626 pos += BUFFSIZE * 2; /* 2 bits per byte in the buffer */
627 }
628 GNUNET_free (rbuff);
629 return bf;
630}
631
632
633/**
634 * Create a bloom filter from raw bits.
635 *
636 * @param data the raw bits in memory (maybe NULL,
637 * in which case all bits should be considered
638 * to be zero).
639 * @param size the size of the bloom-filter (number of
640 * bytes of storage space to use); also size of data
641 * -- unless data is NULL
642 * @param k the number of GNUNET_CRYPTO_hash-functions to apply per
643 * element (number of bits set per element in the set)
644 * @return the bloomfilter
645 */
646struct GNUNET_CONTAINER_BloomFilter *
647GNUNET_CONTAINER_bloomfilter_init (const char *data,
648 size_t size,
649 unsigned int k)
650{
651 struct GNUNET_CONTAINER_BloomFilter *bf;
652
653 if ((0 == k) || (0 == size))
654 return NULL;
655 bf = GNUNET_new (struct GNUNET_CONTAINER_BloomFilter);
656 bf->filename = NULL;
657 bf->fh = NULL;
658 bf->bitArray = GNUNET_malloc_large (size);
659 if (NULL == bf->bitArray)
660 {
661 GNUNET_free (bf);
662 return NULL;
663 }
664 bf->bitArraySize = size;
665 bf->addressesPerElement = k;
666 if (NULL != data)
667 GNUNET_memcpy (bf->bitArray, data, size);
668 return bf;
669}
670
671
672/**
673 * Copy the raw data of this bloomfilter into
674 * the given data array.
675 *
676 * @param bf bloomfilter to take the raw data from
677 * @param data where to write the data
678 * @param size the size of the given data array
679 * @return #GNUNET_SYSERR if the data array is not big enough
680 */
681int
682GNUNET_CONTAINER_bloomfilter_get_raw_data (
683 const struct GNUNET_CONTAINER_BloomFilter *bf,
684 char *data,
685 size_t size)
686{
687 if (NULL == bf)
688 return GNUNET_SYSERR;
689 if (bf->bitArraySize != size)
690 return GNUNET_SYSERR;
691 GNUNET_memcpy (data, bf->bitArray, size);
692 return GNUNET_OK;
693}
694
695
696/**
697 * Free the space associated with a filter
698 * in memory, flush to drive if needed (do not
699 * free the space on the drive)
700 *
701 * @param bf the filter
702 */
703void
704GNUNET_CONTAINER_bloomfilter_free (struct GNUNET_CONTAINER_BloomFilter *bf)
705{
706 if (NULL == bf)
707 return;
708 if (bf->fh != NULL)
709 GNUNET_DISK_file_close (bf->fh);
710 GNUNET_free (bf->filename);
711 GNUNET_free (bf->bitArray);
712 GNUNET_free (bf);
713}
714
715
716/**
717 * Reset a bloom filter to empty. Clears the file on disk.
718 *
719 * @param bf the filter
720 */
721void
722GNUNET_CONTAINER_bloomfilter_clear (struct GNUNET_CONTAINER_BloomFilter *bf)
723{
724 if (NULL == bf)
725 return;
726
727 memset (bf->bitArray, 0, bf->bitArraySize);
728 if (bf->filename != NULL)
729 make_empty_file (bf->fh, bf->bitArraySize * 4LL);
730}
731
732
733/**
734 * Test if an element is in the filter.
735 *
736 * @param e the element
737 * @param bf the filter
738 * @return #GNUNET_YES if the element is in the filter, #GNUNET_NO if not
739 */
740int
741GNUNET_CONTAINER_bloomfilter_test (
742 const struct GNUNET_CONTAINER_BloomFilter *bf,
743 const struct GNUNET_HashCode *e)
744{
745 int res;
746
747 if (NULL == bf)
748 return GNUNET_YES;
749 res = GNUNET_YES;
750 iterateBits (bf, &testBitCallback, &res, e);
751 return res;
752}
753
754
755/**
756 * Add an element to the filter
757 *
758 * @param bf the filter
759 * @param e the element
760 */
761void
762GNUNET_CONTAINER_bloomfilter_add (struct GNUNET_CONTAINER_BloomFilter *bf,
763 const struct GNUNET_HashCode *e)
764{
765 if (NULL == bf)
766 return;
767 iterateBits (bf, &incrementBitCallback, bf, e);
768}
769
770
771/**
772 * Or the entries of the given raw data array with the
773 * data of the given bloom filter. Assumes that
774 * the size of the data array and the current filter
775 * match.
776 *
777 * @param bf the filter
778 * @param data the data to or-in
779 * @param size number of bytes in data
780 */
781int
782GNUNET_CONTAINER_bloomfilter_or (struct GNUNET_CONTAINER_BloomFilter *bf,
783 const char *data,
784 size_t size)
785{
786 unsigned int i;
787 unsigned int n;
788 unsigned long long *fc;
789 const unsigned long long *dc;
790
791 if (NULL == bf)
792 return GNUNET_YES;
793 if (bf->bitArraySize != size)
794 return GNUNET_SYSERR;
795 fc = (unsigned long long *) bf->bitArray;
796 dc = (const unsigned long long *) data;
797 n = size / sizeof(unsigned long long);
798
799 for (i = 0; i < n; i++)
800 fc[i] |= dc[i];
801 for (i = n * sizeof(unsigned long long); i < size; i++)
802 bf->bitArray[i] |= data[i];
803 return GNUNET_OK;
804}
805
806
807/**
808 * Or the entries of the given raw data array with the
809 * data of the given bloom filter. Assumes that
810 * the size of the data array and the current filter
811 * match.
812 *
813 * @param bf the filter
814 * @param to_or the bloomfilter to or-in
815 * @return #GNUNET_OK on success
816 */
817int
818GNUNET_CONTAINER_bloomfilter_or2 (
819 struct GNUNET_CONTAINER_BloomFilter *bf,
820 const struct GNUNET_CONTAINER_BloomFilter *to_or)
821{
822 unsigned int i;
823 unsigned int n;
824 unsigned long long *fc;
825 const unsigned long long *dc;
826 size_t size;
827
828 if (NULL == bf)
829 return GNUNET_OK;
830 if (bf->bitArraySize != to_or->bitArraySize)
831 {
832 GNUNET_break (0);
833 return GNUNET_SYSERR;
834 }
835 size = bf->bitArraySize;
836 fc = (unsigned long long *) bf->bitArray;
837 dc = (const unsigned long long *) to_or->bitArray;
838 n = size / sizeof(unsigned long long);
839
840 for (i = 0; i < n; i++)
841 fc[i] |= dc[i];
842 for (i = n * sizeof(unsigned long long); i < size; i++)
843 bf->bitArray[i] |= to_or->bitArray[i];
844 return GNUNET_OK;
845}
846
847
848/**
849 * Remove an element from the filter.
850 *
851 * @param bf the filter
852 * @param e the element to remove
853 */
854void
855GNUNET_CONTAINER_bloomfilter_remove (struct GNUNET_CONTAINER_BloomFilter *bf,
856 const struct GNUNET_HashCode *e)
857{
858 if (NULL == bf)
859 return;
860 if (NULL == bf->filename)
861 return;
862 iterateBits (bf, &decrementBitCallback, bf, e);
863}
864
865
866/**
867 * Resize a bloom filter. Note that this operation
868 * is pretty costly. Essentially, the bloom filter
869 * needs to be completely re-build.
870 *
871 * @param bf the filter
872 * @param iterator an iterator over all elements stored in the BF
873 * @param iterator_cls argument to the iterator function
874 * @param size the new size for the filter
875 * @param k the new number of GNUNET_CRYPTO_hash-function to apply per element
876 */
877void
878GNUNET_CONTAINER_bloomfilter_resize (struct GNUNET_CONTAINER_BloomFilter *bf,
879 GNUNET_CONTAINER_HashCodeIterator iterator,
880 void *iterator_cls,
881 size_t size,
882 unsigned int k)
883{
884 struct GNUNET_HashCode hc;
885 unsigned int i;
886
887 GNUNET_free (bf->bitArray);
888 i = 1;
889 while (i < size)
890 i *= 2;
891 size = i; /* make sure it's a power of 2 */
892 bf->addressesPerElement = k;
893 bf->bitArraySize = size;
894 bf->bitArray = GNUNET_malloc (size);
895 if (NULL != bf->filename)
896 make_empty_file (bf->fh, bf->bitArraySize * 4LL);
897 while (GNUNET_YES == iterator (iterator_cls, &hc))
898 GNUNET_CONTAINER_bloomfilter_add (bf, &hc);
899}
900
901
902/* end of container_bloomfilter.c */