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author | Florian Dold <florian.dold@gmail.com> | 2013-05-22 10:29:15 +0000 |
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committer | Florian Dold <florian.dold@gmail.com> | 2013-05-22 10:29:15 +0000 |
commit | 4289fca5aeefd0652ae60bc16f90ed911c7e1c60 (patch) | |
tree | da266c48ada44f11ce88a38833960b0eb08c1c5d /src/consensus/ibf.c | |
parent | 3418f171c455980c99ac6363a74116243bddede6 (diff) | |
download | gnunet-4289fca5aeefd0652ae60bc16f90ed911c7e1c60.tar.gz gnunet-4289fca5aeefd0652ae60bc16f90ed911c7e1c60.zip |
- moved MQ to util
- MQ support for stream
- set api
- starting to use set for consensus
Diffstat (limited to 'src/consensus/ibf.c')
-rw-r--r-- | src/consensus/ibf.c | 357 |
1 files changed, 0 insertions, 357 deletions
diff --git a/src/consensus/ibf.c b/src/consensus/ibf.c deleted file mode 100644 index 739b97339..000000000 --- a/src/consensus/ibf.c +++ /dev/null | |||
@@ -1,357 +0,0 @@ | |||
1 | /* | ||
2 | This file is part of GNUnet | ||
3 | (C) 2012 Christian Grothoff (and other contributing authors) | ||
4 | |||
5 | GNUnet is free software; you can redistribute it and/or modify | ||
6 | it under the terms of the GNU General Public License as published | ||
7 | by the Free Software Foundation; either version 2, or (at your | ||
8 | 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 | General Public License for more details. | ||
14 | |||
15 | You should have received a copy of the GNU General Public License | ||
16 | along with GNUnet; see the file COPYING. If not, write to the | ||
17 | Free Software Foundation, Inc., 59 Temple Place - Suite 330, | ||
18 | Boston, MA 02111-1307, USA. | ||
19 | */ | ||
20 | |||
21 | /** | ||
22 | * @file consensus/ibf.c | ||
23 | * @brief implementation of the invertible bloom filter | ||
24 | * @author Florian Dold | ||
25 | */ | ||
26 | |||
27 | #include "ibf.h" | ||
28 | |||
29 | /** | ||
30 | * Create a key from a hashcode. | ||
31 | * | ||
32 | * @param hash the hashcode | ||
33 | * @return a key | ||
34 | */ | ||
35 | struct IBF_Key | ||
36 | ibf_key_from_hashcode (const struct GNUNET_HashCode *hash) | ||
37 | { | ||
38 | /* FIXME: endianess */ | ||
39 | return *(struct IBF_Key *) hash; | ||
40 | } | ||
41 | |||
42 | /** | ||
43 | * Create a hashcode from a key, by replicating the key | ||
44 | * until the hascode is filled | ||
45 | * | ||
46 | * @param key the key | ||
47 | * @param dst hashcode to store the result in | ||
48 | */ | ||
49 | void | ||
50 | ibf_hashcode_from_key (struct IBF_Key key, struct GNUNET_HashCode *dst) | ||
51 | { | ||
52 | struct IBF_Key *p; | ||
53 | unsigned int i; | ||
54 | const unsigned int keys_per_hashcode = sizeof (struct GNUNET_HashCode) / sizeof (struct IBF_Key); | ||
55 | p = (struct IBF_Key *) dst; | ||
56 | for (i = 0; i < keys_per_hashcode; i++) | ||
57 | *p++ = key; | ||
58 | } | ||
59 | |||
60 | |||
61 | /** | ||
62 | * Create an invertible bloom filter. | ||
63 | * | ||
64 | * @param size number of IBF buckets | ||
65 | * @param hash_num number of buckets one element is hashed in | ||
66 | * @return the newly created invertible bloom filter | ||
67 | */ | ||
68 | struct InvertibleBloomFilter * | ||
69 | ibf_create (uint32_t size, uint8_t hash_num) | ||
70 | { | ||
71 | struct InvertibleBloomFilter *ibf; | ||
72 | |||
73 | /* TODO: use malloc_large */ | ||
74 | |||
75 | ibf = GNUNET_malloc (sizeof (struct InvertibleBloomFilter)); | ||
76 | ibf->count = GNUNET_malloc (size * sizeof (uint8_t)); | ||
77 | ibf->key_sum = GNUNET_malloc (size * sizeof (struct GNUNET_HashCode)); | ||
78 | ibf->key_hash_sum = GNUNET_malloc (size * sizeof (struct GNUNET_HashCode)); | ||
79 | ibf->size = size; | ||
80 | ibf->hash_num = hash_num; | ||
81 | |||
82 | return ibf; | ||
83 | } | ||
84 | |||
85 | /** | ||
86 | * Store unique bucket indices for the specified key in dst. | ||
87 | */ | ||
88 | static inline void | ||
89 | ibf_get_indices (const struct InvertibleBloomFilter *ibf, | ||
90 | struct IBF_Key key, int *dst) | ||
91 | { | ||
92 | struct GNUNET_HashCode bucket_indices; | ||
93 | unsigned int filled; | ||
94 | int i; | ||
95 | GNUNET_CRYPTO_hash (&key, sizeof key, &bucket_indices); | ||
96 | filled = 0; | ||
97 | for (i = 0; filled < ibf->hash_num; i++) | ||
98 | { | ||
99 | unsigned int bucket; | ||
100 | unsigned int j; | ||
101 | if ( (0 != i) && (0 == (i % 16)) ) | ||
102 | GNUNET_CRYPTO_hash (&bucket_indices, sizeof (struct GNUNET_HashCode), &bucket_indices); | ||
103 | bucket = bucket_indices.bits[i % 16] % ibf->size; | ||
104 | for (j = 0; j < filled; j++) | ||
105 | if (dst[j] == bucket) | ||
106 | goto try_next; | ||
107 | dst[filled++] = bucket; | ||
108 | try_next: ; | ||
109 | } | ||
110 | } | ||
111 | |||
112 | |||
113 | static void | ||
114 | ibf_insert_into (struct InvertibleBloomFilter *ibf, | ||
115 | struct IBF_Key key, | ||
116 | const int *buckets, int side) | ||
117 | { | ||
118 | int i; | ||
119 | struct GNUNET_HashCode key_hash_sha; | ||
120 | struct IBF_KeyHash key_hash; | ||
121 | GNUNET_CRYPTO_hash (&key, sizeof key, &key_hash_sha); | ||
122 | key_hash.key_hash_val = key_hash_sha.bits[0]; | ||
123 | for (i = 0; i < ibf->hash_num; i++) | ||
124 | { | ||
125 | const int bucket = buckets[i]; | ||
126 | ibf->count[bucket].count_val += side; | ||
127 | ibf->key_sum[bucket].key_val ^= key.key_val; | ||
128 | ibf->key_hash_sum[bucket].key_hash_val ^= key_hash.key_hash_val; | ||
129 | } | ||
130 | } | ||
131 | |||
132 | |||
133 | /** | ||
134 | * Insert an element into an IBF. | ||
135 | * | ||
136 | * @param ibf the IBF | ||
137 | * @param key the element's hash code | ||
138 | */ | ||
139 | void | ||
140 | ibf_insert (struct InvertibleBloomFilter *ibf, struct IBF_Key key) | ||
141 | { | ||
142 | int buckets[ibf->hash_num]; | ||
143 | GNUNET_assert (ibf->hash_num <= ibf->size); | ||
144 | ibf_get_indices (ibf, key, buckets); | ||
145 | ibf_insert_into (ibf, key, buckets, 1); | ||
146 | } | ||
147 | |||
148 | /** | ||
149 | * Test is the IBF is empty, i.e. all counts, keys and key hashes are zero. | ||
150 | */ | ||
151 | static int | ||
152 | ibf_is_empty (struct InvertibleBloomFilter *ibf) | ||
153 | { | ||
154 | int i; | ||
155 | for (i = 0; i < ibf->size; i++) | ||
156 | { | ||
157 | if (0 != ibf->count[i].count_val) | ||
158 | return GNUNET_NO; | ||
159 | if (0 != ibf->key_hash_sum[i].key_hash_val) | ||
160 | return GNUNET_NO; | ||
161 | if (0 != ibf->key_sum[i].key_val) | ||
162 | return GNUNET_NO; | ||
163 | } | ||
164 | return GNUNET_YES; | ||
165 | } | ||
166 | |||
167 | |||
168 | /** | ||
169 | * Decode and remove an element from the IBF, if possible. | ||
170 | * | ||
171 | * @param ibf the invertible bloom filter to decode | ||
172 | * @param ret_side sign of the cell's count where the decoded element came from. | ||
173 | * A negative sign indicates that the element was recovered | ||
174 | * resides in an IBF that was previously subtracted from. | ||
175 | * @param ret_id receives the hash code of the decoded element, if successful | ||
176 | * @return GNUNET_YES if decoding an element was successful, | ||
177 | * GNUNET_NO if the IBF is empty, | ||
178 | * GNUNET_SYSERR if the decoding has failed | ||
179 | */ | ||
180 | int | ||
181 | ibf_decode (struct InvertibleBloomFilter *ibf, | ||
182 | int *ret_side, struct IBF_Key *ret_id) | ||
183 | { | ||
184 | struct IBF_KeyHash hash; | ||
185 | int i; | ||
186 | struct GNUNET_HashCode key_hash_sha; | ||
187 | int buckets[ibf->hash_num]; | ||
188 | |||
189 | GNUNET_assert (NULL != ibf); | ||
190 | |||
191 | for (i = 0; i < ibf->size; i++) | ||
192 | { | ||
193 | int j; | ||
194 | int hit; | ||
195 | |||
196 | /* we can only decode from pure buckets */ | ||
197 | if ((1 != ibf->count[i].count_val) && (-1 != ibf->count[i].count_val)) | ||
198 | continue; | ||
199 | |||
200 | GNUNET_CRYPTO_hash (&ibf->key_sum[i], sizeof (struct IBF_Key), &key_hash_sha); | ||
201 | hash.key_hash_val = key_hash_sha.bits[0]; | ||
202 | |||
203 | /* test if the hash matches the key */ | ||
204 | if (hash.key_hash_val != ibf->key_hash_sum[i].key_hash_val) | ||
205 | continue; | ||
206 | |||
207 | /* test if key in bucket hits its own location, | ||
208 | * if not, the key hash was subject to collision */ | ||
209 | hit = GNUNET_NO; | ||
210 | ibf_get_indices (ibf, ibf->key_sum[i], buckets); | ||
211 | for (j = 0; j < ibf->hash_num; j++) | ||
212 | if (buckets[j] == i) | ||
213 | hit = GNUNET_YES; | ||
214 | |||
215 | if (GNUNET_NO == hit) | ||
216 | continue; | ||
217 | |||
218 | if (NULL != ret_side) | ||
219 | *ret_side = ibf->count[i].count_val; | ||
220 | if (NULL != ret_id) | ||
221 | *ret_id = ibf->key_sum[i]; | ||
222 | |||
223 | /* insert on the opposite side, effectively removing the element */ | ||
224 | ibf_insert_into (ibf, ibf->key_sum[i], buckets, -ibf->count[i].count_val); | ||
225 | |||
226 | return GNUNET_YES; | ||
227 | } | ||
228 | |||
229 | if (GNUNET_YES == ibf_is_empty (ibf)) | ||
230 | return GNUNET_NO; | ||
231 | return GNUNET_SYSERR; | ||
232 | } | ||
233 | |||
234 | |||
235 | /** | ||
236 | * Write buckets from an ibf to a buffer. | ||
237 | * Exactly (IBF_BUCKET_SIZE*ibf->size) bytes are written to buf. | ||
238 | * | ||
239 | * @param ibf the ibf to write | ||
240 | * @param start with which bucket to start | ||
241 | * @param count how many buckets to write | ||
242 | * @param buf buffer to write the data to | ||
243 | */ | ||
244 | void | ||
245 | ibf_write_slice (const struct InvertibleBloomFilter *ibf, uint32_t start, uint32_t count, void *buf) | ||
246 | { | ||
247 | struct IBF_Key *key_dst; | ||
248 | struct IBF_KeyHash *key_hash_dst; | ||
249 | struct IBF_Count *count_dst; | ||
250 | |||
251 | GNUNET_assert (start + count <= ibf->size); | ||
252 | |||
253 | /* copy keys */ | ||
254 | key_dst = (struct IBF_Key *) buf; | ||
255 | memcpy (key_dst, ibf->key_sum + start, count * sizeof *key_dst); | ||
256 | key_dst += count; | ||
257 | /* copy key hashes */ | ||
258 | key_hash_dst = (struct IBF_KeyHash *) key_dst; | ||
259 | memcpy (key_hash_dst, ibf->key_hash_sum + start, count * sizeof *key_hash_dst); | ||
260 | key_hash_dst += count; | ||
261 | /* copy counts */ | ||
262 | count_dst = (struct IBF_Count *) key_hash_dst; | ||
263 | memcpy (count_dst, ibf->count + start, count * sizeof *count_dst); | ||
264 | count_dst += count; | ||
265 | } | ||
266 | |||
267 | |||
268 | /** | ||
269 | * Read buckets from a buffer into an ibf. | ||
270 | * | ||
271 | * @param buf pointer to the buffer to read from | ||
272 | * @param start which bucket to start at | ||
273 | * @param count how many buckets to read | ||
274 | * @param ibf the ibf to read from | ||
275 | */ | ||
276 | void | ||
277 | ibf_read_slice (const void *buf, uint32_t start, uint32_t count, struct InvertibleBloomFilter *ibf) | ||
278 | { | ||
279 | struct IBF_Key *key_src; | ||
280 | struct IBF_KeyHash *key_hash_src; | ||
281 | struct IBF_Count *count_src; | ||
282 | |||
283 | GNUNET_assert (start + count <= ibf->size); | ||
284 | |||
285 | /* copy keys */ | ||
286 | key_src = (struct IBF_Key *) buf; | ||
287 | memcpy (ibf->key_sum + start, key_src, count * sizeof *key_src); | ||
288 | key_src += count; | ||
289 | /* copy key hashes */ | ||
290 | key_hash_src = (struct IBF_KeyHash *) key_src; | ||
291 | memcpy (ibf->key_hash_sum + start, key_hash_src, count * sizeof *key_hash_src); | ||
292 | key_hash_src += count; | ||
293 | /* copy counts */ | ||
294 | count_src = (struct IBF_Count *) key_hash_src; | ||
295 | memcpy (ibf->count + start, count_src, count * sizeof *count_src); | ||
296 | count_src += count; | ||
297 | } | ||
298 | |||
299 | |||
300 | /** | ||
301 | * Subtract ibf2 from ibf1, storing the result in ibf1. | ||
302 | * The two IBF's must have the same parameters size and hash_num. | ||
303 | * | ||
304 | * @param ibf1 IBF that is subtracted from | ||
305 | * @param ibf2 IBF that will be subtracted from ibf1 | ||
306 | */ | ||
307 | void | ||
308 | ibf_subtract (struct InvertibleBloomFilter *ibf1, const struct InvertibleBloomFilter *ibf2) | ||
309 | { | ||
310 | int i; | ||
311 | |||
312 | GNUNET_assert (ibf1->size == ibf2->size); | ||
313 | GNUNET_assert (ibf1->hash_num == ibf2->hash_num); | ||
314 | |||
315 | for (i = 0; i < ibf1->size; i++) | ||
316 | { | ||
317 | ibf1->count[i].count_val -= ibf2->count[i].count_val; | ||
318 | ibf1->key_hash_sum[i].key_hash_val ^= ibf2->key_hash_sum[i].key_hash_val; | ||
319 | ibf1->key_sum[i].key_val ^= ibf2->key_sum[i].key_val; | ||
320 | } | ||
321 | } | ||
322 | |||
323 | |||
324 | /** | ||
325 | * Create a copy of an IBF, the copy has to be destroyed properly. | ||
326 | * | ||
327 | * @param ibf the IBF to copy | ||
328 | */ | ||
329 | struct InvertibleBloomFilter * | ||
330 | ibf_dup (const struct InvertibleBloomFilter *ibf) | ||
331 | { | ||
332 | struct InvertibleBloomFilter *copy; | ||
333 | copy = GNUNET_malloc (sizeof *copy); | ||
334 | copy->hash_num = ibf->hash_num; | ||
335 | copy->size = ibf->size; | ||
336 | copy->key_hash_sum = GNUNET_memdup (ibf->key_hash_sum, ibf->size * sizeof (struct IBF_KeyHash)); | ||
337 | copy->key_sum = GNUNET_memdup (ibf->key_sum, ibf->size * sizeof (struct IBF_Key)); | ||
338 | copy->count = GNUNET_memdup (ibf->count, ibf->size * sizeof (struct IBF_Count)); | ||
339 | return copy; | ||
340 | } | ||
341 | |||
342 | |||
343 | /** | ||
344 | * Destroy all resources associated with the invertible bloom filter. | ||
345 | * No more ibf_*-functions may be called on ibf after calling destroy. | ||
346 | * | ||
347 | * @param ibf the intertible bloom filter to destroy | ||
348 | */ | ||
349 | void | ||
350 | ibf_destroy (struct InvertibleBloomFilter *ibf) | ||
351 | { | ||
352 | GNUNET_free (ibf->key_sum); | ||
353 | GNUNET_free (ibf->key_hash_sum); | ||
354 | GNUNET_free (ibf->count); | ||
355 | GNUNET_free (ibf); | ||
356 | } | ||
357 | |||