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1/*␊
2Copyright (c) 2003-2012, Troy D. Hanson http://uthash.sourceforge.net␊
3All rights reserved.␊
4␊
5Redistribution and use in source and binary forms, with or without␊
6modification, are permitted provided that the following conditions are met:␊
7␊
8 * Redistributions of source code must retain the above copyright␊
9 notice, this list of conditions and the following disclaimer.␊
10␊
11THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS␊
12IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED␊
13TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A␊
14PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER␊
15OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,␊
16EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,␊
17PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR␊
18PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF␊
19LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING␊
20NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS␊
21SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.␊
22*/␊
23␊
24#ifndef UTHASH_H␊
25#define UTHASH_H ␊
26␊
27#include "libsaio.h"␊
28␊
29/* These macros use decltype or the earlier __typeof GNU extension.␊
30 As decltype is only available in newer compilers (VS2010 or gcc 4.3+␊
31 when compiling c++ source) this code uses whatever method is needed␊
32 or, for VS2008 where neither is available, uses casting workarounds. */␊
33#ifdef _MSC_VER /* MS compiler */␊
34#if _MSC_VER >= 1600 && defined(__cplusplus) /* VS2010 or newer in C++ mode */␊
35#define DECLTYPE(x) (decltype(x))␊
36#else /* VS2008 or older (or VS2010 in C mode) */␊
37#define NO_DECLTYPE␊
38#define DECLTYPE(x)␊
39#endif␊
40#else /* GNU, Sun and other compilers */␊
41#define DECLTYPE(x) (__typeof(x))␊
42#endif␊
43␊
44#ifdef NO_DECLTYPE␊
45#define DECLTYPE_ASSIGN(dst,src) \␊
46do { \␊
47 char **_da_dst = (char**)(&(dst)); \␊
48 *_da_dst = (char*)(src); \␊
49} while(0)␊
50#else ␊
51#define DECLTYPE_ASSIGN(dst,src) \␊
52do { \␊
53 (dst) = DECLTYPE(dst)(src); \␊
54} while(0)␊
55#endif␊
56␊
57#define UTHASH_VERSION 1.9.6␊
58␊
59#ifndef uthash_fatal␊
60#define uthash_fatal(msg) longjmp(uterror,-1) /* fatal error (out of memory,etc) */␊
61#endif␊
62#ifndef uthash_malloc␊
63#define uthash_malloc(sz) malloc(sz) /* malloc fcn */␊
64#endif␊
65#ifndef uthash_free␊
66#define uthash_free(ptr,sz) free(ptr) /* free fcn */␊
67#endif␊
68#ifndef uthash_noexpand_fyi␊
69#define uthash_noexpand_fyi(tbl) /* can be defined to log noexpand */␊
70#endif␊
71#ifndef uthash_expand_fyi␊
72#define uthash_expand_fyi(tbl) /* can be defined to log expands */␊
73#endif␊
74␊
75/* initial number of buckets */␊
76#define HASH_INITIAL_NUM_BUCKETS 32 /* initial number of buckets */␊
77#define HASH_INITIAL_NUM_BUCKETS_LOG2 5 /* lg2 of initial number of buckets */␊
78#define HASH_BKT_CAPACITY_THRESH 10 /* expand when bucket count reaches */␊
79␊
80/* calculate the element whose hash handle address is hhe */␊
81#define ELMT_FROM_HH(tbl,hhp) ((void*)(((char*)(hhp)) - ((tbl)->hho)))␊
82␊
83#define HASH_FIND(hh,head,keyptr,keylen,out) \␊
84do { \␊
85 unsigned _hf_bkt,_hf_hashv; \␊
86 out=NULL; \␊
87 if (head) { \␊
88 HASH_FCN(keyptr,keylen, (head)->hh.tbl->num_buckets, _hf_hashv, _hf_bkt); \␊
89 if (HASH_BLOOM_TEST((head)->hh.tbl, _hf_hashv)) { \␊
90 HASH_FIND_IN_BKT((head)->hh.tbl, hh, (head)->hh.tbl->buckets[ _hf_bkt ], \␊
91 keyptr,keylen,out); \␊
92 } \␊
93 } \␊
94} while (0)␊
95␊
96#ifdef HASH_BLOOM␊
97#define HASH_BLOOM_BITLEN (1ULL << HASH_BLOOM)␊
98#define HASH_BLOOM_BYTELEN (HASH_BLOOM_BITLEN/8) + ((HASH_BLOOM_BITLEN%8) ? 1:0)␊
99#define HASH_BLOOM_MAKE(tbl) \␊
100do { \␊
101 (tbl)->bloom_nbits = HASH_BLOOM; \␊
102 (tbl)->bloom_bv = (uint8_t*)uthash_malloc(HASH_BLOOM_BYTELEN); \␊
103 if (!((tbl)->bloom_bv)) { uthash_fatal( "out of memory"); } \␊
104 memset((tbl)->bloom_bv, 0, HASH_BLOOM_BYTELEN); \␊
105 (tbl)->bloom_sig = HASH_BLOOM_SIGNATURE; \␊
106} while (0)␊
107␊
108#define HASH_BLOOM_FREE(tbl) \␊
109do { \␊
110 uthash_free((tbl)->bloom_bv, HASH_BLOOM_BYTELEN); \␊
111} while (0)␊
112␊
113#define HASH_BLOOM_BITSET(bv,idx) (bv[(idx)/8] |= (1U << ((idx)%8)))␊
114#define HASH_BLOOM_BITTEST(bv,idx) (bv[(idx)/8] & (1U << ((idx)%8)))␊
115␊
116#define HASH_BLOOM_ADD(tbl,hashv) \␊
117 HASH_BLOOM_BITSET((tbl)->bloom_bv, (hashv & (uint32_t)((1ULL << (tbl)->bloom_nbits) - 1)))␊
118␊
119#define HASH_BLOOM_TEST(tbl,hashv) \␊
120 HASH_BLOOM_BITTEST((tbl)->bloom_bv, (hashv & (uint32_t)((1ULL << (tbl)->bloom_nbits) - 1)))␊
121␊
122#else␊
123#define HASH_BLOOM_MAKE(tbl) ␊
124#define HASH_BLOOM_FREE(tbl) ␊
125#define HASH_BLOOM_ADD(tbl,hashv) ␊
126#define HASH_BLOOM_TEST(tbl,hashv) (1)␊
127#endif␊
128␊
129#define HASH_MAKE_TABLE(hh,head) \␊
130do { \␊
131 (head)->hh.tbl = (UT_hash_table*)uthash_malloc( \␊
132 sizeof(UT_hash_table)); \␊
133 if (!((head)->hh.tbl)) { uthash_fatal( "out of memory"); } \␊
134 memset((head)->hh.tbl, 0, sizeof(UT_hash_table)); \␊
135 (head)->hh.tbl->tail = &((head)->hh); \␊
136 (head)->hh.tbl->num_buckets = HASH_INITIAL_NUM_BUCKETS; \␊
137 (head)->hh.tbl->log2_num_buckets = HASH_INITIAL_NUM_BUCKETS_LOG2; \␊
138 (head)->hh.tbl->hho = (char*)(&(head)->hh) - (char*)(head); \␊
139 (head)->hh.tbl->buckets = (UT_hash_bucket*)uthash_malloc( \␊
140 HASH_INITIAL_NUM_BUCKETS*sizeof(struct UT_hash_bucket)); \␊
141 if (! (head)->hh.tbl->buckets) { uthash_fatal( "out of memory"); } \␊
142 memset((head)->hh.tbl->buckets, 0, \␊
143 HASH_INITIAL_NUM_BUCKETS*sizeof(struct UT_hash_bucket)); \␊
144 HASH_BLOOM_MAKE((head)->hh.tbl); \␊
145 (head)->hh.tbl->signature = HASH_SIGNATURE; \␊
146} while(0)␊
147␊
148#define HASH_ADD(hh,head,fieldname,keylen_in,add) \␊
149 HASH_ADD_KEYPTR(hh,head,&((add)->fieldname),keylen_in,add)␊
150 ␊
151#define HASH_ADD_KEYPTR(hh,head,keyptr,keylen_in,add) \␊
152do { \␊
153 unsigned _ha_bkt; \␊
154 (add)->hh.next = NULL; \␊
155 (add)->hh.key = (char*)keyptr; \␊
156 (add)->hh.keylen = (unsigned)keylen_in; \␊
157 if (!(head)) { \␊
158 head = (add); \␊
159 (head)->hh.prev = NULL; \␊
160 HASH_MAKE_TABLE(hh,head); \␊
161 } else { \␊
162 (head)->hh.tbl->tail->next = (add); \␊
163 (add)->hh.prev = ELMT_FROM_HH((head)->hh.tbl, (head)->hh.tbl->tail); \␊
164 (head)->hh.tbl->tail = &((add)->hh); \␊
165 } \␊
166 (head)->hh.tbl->num_items++; \␊
167 (add)->hh.tbl = (head)->hh.tbl; \␊
168 HASH_FCN(keyptr,keylen_in, (head)->hh.tbl->num_buckets, \␊
169 (add)->hh.hashv, _ha_bkt); \␊
170 HASH_ADD_TO_BKT((head)->hh.tbl->buckets[_ha_bkt],&(add)->hh); \␊
171 HASH_BLOOM_ADD((head)->hh.tbl,(add)->hh.hashv); \␊
172 HASH_EMIT_KEY(hh,head,keyptr,keylen_in); \␊
173 HASH_FSCK(hh,head); \␊
174} while(0)␊
175␊
176#define HASH_TO_BKT( hashv, num_bkts, bkt ) \␊
177do { \␊
178 bkt = ((hashv) & ((num_bkts) - 1)); \␊
179} while(0)␊
180␊
181/* delete "delptr" from the hash table.␊
182 * "the usual" patch-up process for the app-order doubly-linked-list.␊
183 * The use of _hd_hh_del below deserves special explanation.␊
184 * These used to be expressed using (delptr) but that led to a bug␊
185 * if someone used the same symbol for the head and deletee, like␊
186 * HASH_DELETE(hh,users,users);␊
187 * We want that to work, but by changing the head (users) below␊
188 * we were forfeiting our ability to further refer to the deletee (users)␊
189 * in the patch-up process. Solution: use scratch space to␊
190 * copy the deletee pointer, then the latter references are via that␊
191 * scratch pointer rather than through the repointed (users) symbol.␊
192 */␊
193#define HASH_DELETE(hh,head,delptr) \␊
194do { \␊
195 unsigned _hd_bkt; \␊
196 struct UT_hash_handle *_hd_hh_del; \␊
197 if ( ((delptr)->hh.prev == NULL) && ((delptr)->hh.next == NULL) ) { \␊
198 uthash_free((head)->hh.tbl->buckets, \␊
199 (head)->hh.tbl->num_buckets*sizeof(struct UT_hash_bucket) ); \␊
200 HASH_BLOOM_FREE((head)->hh.tbl); \␊
201 uthash_free((head)->hh.tbl, sizeof(UT_hash_table)); \␊
202 head = NULL; \␊
203 } else { \␊
204 _hd_hh_del = &((delptr)->hh); \␊
205 if ((delptr) == ELMT_FROM_HH((head)->hh.tbl,(head)->hh.tbl->tail)) { \␊
206 (head)->hh.tbl->tail = \␊
207 (UT_hash_handle*)((char*)((delptr)->hh.prev) + \␊
208 (head)->hh.tbl->hho); \␊
209 } \␊
210 if ((delptr)->hh.prev) { \␊
211 ((UT_hash_handle*)((char*)((delptr)->hh.prev) + \␊
212 (head)->hh.tbl->hho))->next = (delptr)->hh.next; \␊
213 } else { \␊
214 DECLTYPE_ASSIGN(head,(delptr)->hh.next); \␊
215 } \␊
216 if (_hd_hh_del->next) { \␊
217 ((UT_hash_handle*)((char*)_hd_hh_del->next + \␊
218 (head)->hh.tbl->hho))->prev = \␊
219 _hd_hh_del->prev; \␊
220 } \␊
221 HASH_TO_BKT( _hd_hh_del->hashv, (head)->hh.tbl->num_buckets, _hd_bkt); \␊
222 HASH_DEL_IN_BKT(hh,(head)->hh.tbl->buckets[_hd_bkt], _hd_hh_del); \␊
223 (head)->hh.tbl->num_items--; \␊
224 } \␊
225 HASH_FSCK(hh,head); \␊
226} while (0)␊
227␊
228␊
229/* convenience forms of HASH_FIND/HASH_ADD/HASH_DEL */␊
230#define HASH_FIND_STR(head,findstr,out) \␊
231 HASH_FIND(hh,head,findstr,strlen(findstr),out)␊
232#define HASH_ADD_STR(head,strfield,add) \␊
233 HASH_ADD(hh,head,strfield,strlen(add->strfield),add)␊
234#define HASH_FIND_INT(head,findint,out) \␊
235 HASH_FIND(hh,head,findint,sizeof(int),out)␊
236#define HASH_ADD_INT(head,intfield,add) \␊
237 HASH_ADD(hh,head,intfield,sizeof(int),add)␊
238#define HASH_FIND_PTR(head,findptr,out) \␊
239 HASH_FIND(hh,head,findptr,sizeof(void *),out)␊
240#define HASH_ADD_PTR(head,ptrfield,add) \␊
241 HASH_ADD(hh,head,ptrfield,sizeof(void *),add)␊
242#define HASH_DEL(head,delptr) \␊
243 HASH_DELETE(hh,head,delptr)␊
244␊
245/* HASH_FSCK checks hash integrity on every add/delete when HASH_DEBUG is defined.␊
246 * This is for uthash developer only; it compiles away if HASH_DEBUG isn't defined.␊
247 */␊
248#ifdef HASH_DEBUG␊
249#define HASH_OOPS(...) do { printf("%s\n"__VA_ARGS__); longjmp(THIS_BUF_ERROR,-1); } while (0)␊
250#define HASH_FSCK(hh,head) \␊
251do { \␊
252 unsigned _bkt_i; \␊
253 unsigned _count, _bkt_count; \␊
254 char *_prev; \␊
255 struct UT_hash_handle *_thh; \␊
256 if (head) { \␊
257 _count = 0; \␊
258 for( _bkt_i = 0; _bkt_i < (head)->hh.tbl->num_buckets; _bkt_i++) { \␊
259 _bkt_count = 0; \␊
260 _thh = (head)->hh.tbl->buckets[_bkt_i].hh_head; \␊
261 _prev = NULL; \␊
262 while (_thh) { \␊
263 if (_prev != (char*)(_thh->hh_prev)) { \␊
264 HASH_OOPS("invalid hh_prev %p, actual %p\n", \␊
265 _thh->hh_prev, _prev ); \␊
266 } \␊
267 _bkt_count++; \␊
268 _prev = (char*)(_thh); \␊
269 _thh = _thh->hh_next; \␊
270 } \␊
271 _count += _bkt_count; \␊
272 if ((head)->hh.tbl->buckets[_bkt_i].count != _bkt_count) { \␊
273 HASH_OOPS("invalid bucket count %d, actual %d\n", \␊
274 (head)->hh.tbl->buckets[_bkt_i].count, _bkt_count); \␊
275 } \␊
276 } \␊
277 if (_count != (head)->hh.tbl->num_items) { \␊
278 HASH_OOPS("invalid hh item count %d, actual %d\n", \␊
279 (head)->hh.tbl->num_items, _count ); \␊
280 } \␊
281 /* traverse hh in app order; check next/prev integrity, count */ \␊
282 _count = 0; \␊
283 _prev = NULL; \␊
284 _thh = &(head)->hh; \␊
285 while (_thh) { \␊
286 _count++; \␊
287 if (_prev !=(char*)(_thh->prev)) { \␊
288 HASH_OOPS("invalid prev %p, actual %p\n", \␊
289 _thh->prev, _prev ); \␊
290 } \␊
291 _prev = (char*)ELMT_FROM_HH((head)->hh.tbl, _thh); \␊
292 _thh = ( _thh->next ? (UT_hash_handle*)((char*)(_thh->next) + \␊
293 (head)->hh.tbl->hho) : NULL ); \␊
294 } \␊
295 if (_count != (head)->hh.tbl->num_items) { \␊
296 HASH_OOPS("invalid app item count %d, actual %d\n", \␊
297 (head)->hh.tbl->num_items, _count ); \␊
298 } \␊
299 } \␊
300} while (0)␊
301#else␊
302#define HASH_FSCK(hh,head) ␊
303#endif␊
304␊
305/* When compiled with -DHASH_EMIT_KEYS, length-prefixed keys are emitted to ␊
306 * the descriptor to which this macro is defined for tuning the hash function.␊
307 * The app can #include <unistd.h> to get the prototype for write(2). */␊
308#ifdef HASH_EMIT_KEYS␊
309#define HASH_EMIT_KEY(hh,head,keyptr,fieldlen) \␊
310do { \␊
311 unsigned _klen = fieldlen; \␊
312 write(HASH_EMIT_KEYS, &_klen, sizeof(_klen)); \␊
313 write(HASH_EMIT_KEYS, keyptr, fieldlen); \␊
314} while (0)␊
315#else ␊
316#define HASH_EMIT_KEY(hh,head,keyptr,fieldlen) ␊
317#endif␊
318␊
319/* default to Jenkin's hash unless overridden e.g. DHASH_FUNCTION=HASH_SAX */␊
320#ifdef HASH_FUNCTION ␊
321#define HASH_FCN HASH_FUNCTION␊
322#else␊
323#define HASH_FCN HASH_JEN␊
324#endif␊
325␊
326/* The Bernstein hash function, used in Perl prior to v5.6 */␊
327#define HASH_BER(key,keylen,num_bkts,hashv,bkt) \␊
328do { \␊
329 unsigned _hb_keylen=keylen; \␊
330 char *_hb_key=(char*)(key); \␊
331 (hashv) = 0; \␊
332 while (_hb_keylen--) { (hashv) = ((hashv) * 33) + *_hb_key++; } \␊
333 bkt = (hashv) & (num_bkts-1); \␊
334} while (0)␊
335␊
336␊
337/* SAX/FNV/OAT/JEN hash functions are macro variants of those listed at ␊
338 * http://eternallyconfuzzled.com/tuts/algorithms/jsw_tut_hashing.aspx */␊
339#define HASH_SAX(key,keylen,num_bkts,hashv,bkt) \␊
340do { \␊
341 unsigned _sx_i; \␊
342 char *_hs_key=(char*)(key); \␊
343 hashv = 0; \␊
344 for(_sx_i=0; _sx_i < keylen; _sx_i++) \␊
345 hashv ^= (hashv << 5) + (hashv >> 2) + _hs_key[_sx_i]; \␊
346 bkt = hashv & (num_bkts-1); \␊
347} while (0)␊
348␊
349#define HASH_FNV(key,keylen,num_bkts,hashv,bkt) \␊
350do { \␊
351 unsigned _fn_i; \␊
352 char *_hf_key=(char*)(key); \␊
353 hashv = 2166136261UL; \␊
354 for(_fn_i=0; _fn_i < keylen; _fn_i++) \␊
355 hashv = (hashv * 16777619) ^ _hf_key[_fn_i]; \␊
356 bkt = hashv & (num_bkts-1); \␊
357} while(0)␊
358 ␊
359#define HASH_OAT(key,keylen,num_bkts,hashv,bkt) \␊
360do { \␊
361 unsigned _ho_i; \␊
362 char *_ho_key=(char*)(key); \␊
363 hashv = 0; \␊
364 for(_ho_i=0; _ho_i < keylen; _ho_i++) { \␊
365 hashv += _ho_key[_ho_i]; \␊
366 hashv += (hashv << 10); \␊
367 hashv ^= (hashv >> 6); \␊
368 } \␊
369 hashv += (hashv << 3); \␊
370 hashv ^= (hashv >> 11); \␊
371 hashv += (hashv << 15); \␊
372 bkt = hashv & (num_bkts-1); \␊
373} while(0)␊
374␊
375#define HASH_JEN_MIX(a,b,c) \␊
376do { \␊
377 a -= b; a -= c; a ^= ( c >> 13 ); \␊
378 b -= c; b -= a; b ^= ( a << 8 ); \␊
379 c -= a; c -= b; c ^= ( b >> 13 ); \␊
380 a -= b; a -= c; a ^= ( c >> 12 ); \␊
381 b -= c; b -= a; b ^= ( a << 16 ); \␊
382 c -= a; c -= b; c ^= ( b >> 5 ); \␊
383 a -= b; a -= c; a ^= ( c >> 3 ); \␊
384 b -= c; b -= a; b ^= ( a << 10 ); \␊
385 c -= a; c -= b; c ^= ( b >> 15 ); \␊
386} while (0)␊
387␊
388#define HASH_JEN(key,keylen,num_bkts,hashv,bkt) \␊
389do { \␊
390 unsigned _hj_i,_hj_j,_hj_k; \␊
391 char *_hj_key=(char*)(key); \␊
392 hashv = 0xfeedbeef; \␊
393 _hj_i = _hj_j = 0x9e3779b9; \␊
394 _hj_k = (unsigned)keylen; \␊
395 while (_hj_k >= 12) { \␊
396 _hj_i += (_hj_key[0] + ( (unsigned)_hj_key[1] << 8 ) \␊
397 + ( (unsigned)_hj_key[2] << 16 ) \␊
398 + ( (unsigned)_hj_key[3] << 24 ) ); \␊
399 _hj_j += (_hj_key[4] + ( (unsigned)_hj_key[5] << 8 ) \␊
400 + ( (unsigned)_hj_key[6] << 16 ) \␊
401 + ( (unsigned)_hj_key[7] << 24 ) ); \␊
402 hashv += (_hj_key[8] + ( (unsigned)_hj_key[9] << 8 ) \␊
403 + ( (unsigned)_hj_key[10] << 16 ) \␊
404 + ( (unsigned)_hj_key[11] << 24 ) ); \␊
405 \␊
406 HASH_JEN_MIX(_hj_i, _hj_j, hashv); \␊
407 \␊
408 _hj_key += 12; \␊
409 _hj_k -= 12; \␊
410 } \␊
411 hashv += keylen; \␊
412 switch ( _hj_k ) { \␊
413 case 11: hashv += ( (unsigned)_hj_key[10] << 24 ); \␊
414 case 10: hashv += ( (unsigned)_hj_key[9] << 16 ); \␊
415 case 9: hashv += ( (unsigned)_hj_key[8] << 8 ); \␊
416 case 8: _hj_j += ( (unsigned)_hj_key[7] << 24 ); \␊
417 case 7: _hj_j += ( (unsigned)_hj_key[6] << 16 ); \␊
418 case 6: _hj_j += ( (unsigned)_hj_key[5] << 8 ); \␊
419 case 5: _hj_j += _hj_key[4]; \␊
420 case 4: _hj_i += ( (unsigned)_hj_key[3] << 24 ); \␊
421 case 3: _hj_i += ( (unsigned)_hj_key[2] << 16 ); \␊
422 case 2: _hj_i += ( (unsigned)_hj_key[1] << 8 ); \␊
423 case 1: _hj_i += _hj_key[0]; \␊
424 } \␊
425 HASH_JEN_MIX(_hj_i, _hj_j, hashv); \␊
426 bkt = hashv & (num_bkts-1); \␊
427} while(0)␊
428␊
429/* The Paul Hsieh hash function */␊
430#undef get16bits␊
431#if (defined(__GNUC__) && defined(__i386__)) || defined(__WATCOMC__) \␊
432 || defined(_MSC_VER) || defined (__BORLANDC__) || defined (__TURBOC__)␊
433#define get16bits(d) (*((const uint16_t *) (d)))␊
434#endif␊
435␊
436#if !defined (get16bits)␊
437#define get16bits(d) ((((uint32_t)(((const uint8_t *)(d))[1])) << 8) \␊
438 +(uint32_t)(((const uint8_t *)(d))[0]) )␊
439#endif␊
440#define HASH_SFH(key,keylen,num_bkts,hashv,bkt) \␊
441do { \␊
442 char *_sfh_key=(char*)(key); \␊
443 uint32_t _sfh_tmp, _sfh_len = keylen; \␊
444 \␊
445 int _sfh_rem = _sfh_len & 3; \␊
446 _sfh_len >>= 2; \␊
447 hashv = 0xcafebabe; \␊
448 \␊
449 /* Main loop */ \␊
450 for (;_sfh_len > 0; _sfh_len--) { \␊
451 hashv += get16bits (_sfh_key); \␊
452 _sfh_tmp = (get16bits (_sfh_key+2) << 11) ^ hashv; \␊
453 hashv = (hashv << 16) ^ _sfh_tmp; \␊
454 _sfh_key += 2*sizeof (uint16_t); \␊
455 hashv += hashv >> 11; \␊
456 } \␊
457 \␊
458 /* Handle end cases */ \␊
459 switch (_sfh_rem) { \␊
460 case 3: hashv += get16bits (_sfh_key); \␊
461 hashv ^= hashv << 16; \␊
462 hashv ^= _sfh_key[sizeof (uint16_t)] << 18; \␊
463 hashv += hashv >> 11; \␊
464 break; \␊
465 case 2: hashv += get16bits (_sfh_key); \␊
466 hashv ^= hashv << 11; \␊
467 hashv += hashv >> 17; \␊
468 break; \␊
469 case 1: hashv += *_sfh_key; \␊
470 hashv ^= hashv << 10; \␊
471 hashv += hashv >> 1; \␊
472 } \␊
473 \␊
474 /* Force "avalanching" of final 127 bits */ \␊
475 hashv ^= hashv << 3; \␊
476 hashv += hashv >> 5; \␊
477 hashv ^= hashv << 4; \␊
478 hashv += hashv >> 17; \␊
479 hashv ^= hashv << 25; \␊
480 hashv += hashv >> 6; \␊
481 bkt = hashv & (num_bkts-1); \␊
482} while(0)␊
483␊
484#ifdef HASH_USING_NO_STRICT_ALIASING␊
485/* The MurmurHash exploits some CPU's (x86,x86_64) tolerance for unaligned reads.␊
486 * For other types of CPU's (e.g. Sparc) an unaligned read causes a bus error.␊
487 * MurmurHash uses the faster approach only on CPU's where we know it's safe. ␊
488 *␊
489 * Note the preprocessor built-in defines can be emitted using:␊
490 *␊
491 * gcc -m64 -dM -E - < /dev/null (on gcc)␊
492 * cc -## a.c (where a.c is a simple test file) (Sun Studio)␊
493 */␊
494#if (defined(__i386__) || defined(__x86_64__)) ␊
495#define MUR_GETBLOCK(p,i) p[i]␊
496#else /* non intel */␊
497#define MUR_PLUS0_ALIGNED(p) (((unsigned long)p & 0x3) == 0)␊
498#define MUR_PLUS1_ALIGNED(p) (((unsigned long)p & 0x3) == 1)␊
499#define MUR_PLUS2_ALIGNED(p) (((unsigned long)p & 0x3) == 2)␊
500#define MUR_PLUS3_ALIGNED(p) (((unsigned long)p & 0x3) == 3)␊
501#define WP(p) ((uint32_t*)((unsigned long)(p) & ~3UL))␊
502#if (defined(__BIG_ENDIAN__) || defined(SPARC) || defined(__ppc__) || defined(__ppc64__))␊
503#define MUR_THREE_ONE(p) ((((*WP(p))&0x00ffffff) << 8) | (((*(WP(p)+1))&0xff000000) >> 24))␊
504#define MUR_TWO_TWO(p) ((((*WP(p))&0x0000ffff) <<16) | (((*(WP(p)+1))&0xffff0000) >> 16))␊
505#define MUR_ONE_THREE(p) ((((*WP(p))&0x000000ff) <<24) | (((*(WP(p)+1))&0xffffff00) >> 8))␊
506#else /* assume little endian non-intel */␊
507#define MUR_THREE_ONE(p) ((((*WP(p))&0xffffff00) >> 8) | (((*(WP(p)+1))&0x000000ff) << 24))␊
508#define MUR_TWO_TWO(p) ((((*WP(p))&0xffff0000) >>16) | (((*(WP(p)+1))&0x0000ffff) << 16))␊
509#define MUR_ONE_THREE(p) ((((*WP(p))&0xff000000) >>24) | (((*(WP(p)+1))&0x00ffffff) << 8))␊
510#endif␊
511#define MUR_GETBLOCK(p,i) (MUR_PLUS0_ALIGNED(p) ? ((p)[i]) : \␊
512 (MUR_PLUS1_ALIGNED(p) ? MUR_THREE_ONE(p) : \␊
513 (MUR_PLUS2_ALIGNED(p) ? MUR_TWO_TWO(p) : \␊
514 MUR_ONE_THREE(p))))␊
515#endif␊
516#define MUR_ROTL32(x,r) (((x) << (r)) | ((x) >> (32 - (r))))␊
517#define MUR_FMIX(_h) \␊
518do { \␊
519 _h ^= _h >> 16; \␊
520 _h *= 0x85ebca6b; \␊
521 _h ^= _h >> 13; \␊
522 _h *= 0xc2b2ae35l; \␊
523 _h ^= _h >> 16; \␊
524} while(0)␊
525␊
526#define HASH_MUR(key,keylen,num_bkts,hashv,bkt) \␊
527do { \␊
528 const uint8_t *_mur_data = (const uint8_t*)(key); \␊
529 const int _mur_nblocks = (keylen) / 4; \␊
530 uint32_t _mur_h1 = 0xf88D5353; \␊
531 uint32_t _mur_c1 = 0xcc9e2d51; \␊
532 uint32_t _mur_c2 = 0x1b873593; \␊
533 const uint32_t *_mur_blocks = (const uint32_t*)(_mur_data+_mur_nblocks*4); \␊
534 int _mur_i; \␊
535 for(_mur_i = -_mur_nblocks; _mur_i; _mur_i++) { \␊
536 uint32_t _mur_k1 = MUR_GETBLOCK(_mur_blocks,_mur_i); \␊
537 _mur_k1 *= _mur_c1; \␊
538 _mur_k1 = MUR_ROTL32(_mur_k1,15); \␊
539 _mur_k1 *= _mur_c2; \␊
540 \␊
541 _mur_h1 ^= _mur_k1; \␊
542 _mur_h1 = MUR_ROTL32(_mur_h1,13); \␊
543 _mur_h1 = _mur_h1*5+0xe6546b64; \␊
544 } \␊
545 const uint8_t *_mur_tail = (const uint8_t*)(_mur_data + _mur_nblocks*4); \␊
546 uint32_t _mur_k1=0; \␊
547 switch((keylen) & 3) { \␊
548 case 3: _mur_k1 ^= _mur_tail[2] << 16; \␊
549 case 2: _mur_k1 ^= _mur_tail[1] << 8; \␊
550 case 1: _mur_k1 ^= _mur_tail[0]; \␊
551 _mur_k1 *= _mur_c1; \␊
552 _mur_k1 = MUR_ROTL32(_mur_k1,15); \␊
553 _mur_k1 *= _mur_c2; \␊
554 _mur_h1 ^= _mur_k1; \␊
555 } \␊
556 _mur_h1 ^= (keylen); \␊
557 MUR_FMIX(_mur_h1); \␊
558 hashv = _mur_h1; \␊
559 bkt = hashv & (num_bkts-1); \␊
560} while(0)␊
561#endif /* HASH_USING_NO_STRICT_ALIASING */␊
562␊
563/* key comparison function; return 0 if keys equal */␊
564#define HASH_KEYCMP(a,b,len) memcmp(a,b,len) ␊
565␊
566/* iterate over items in a known bucket to find desired item */␊
567#define HASH_FIND_IN_BKT(tbl,hh,head,keyptr,keylen_in,out) \␊
568do { \␊
569 if (head.hh_head) DECLTYPE_ASSIGN(out,ELMT_FROM_HH(tbl,head.hh_head)); \␊
570 else out=NULL; \␊
571 while (out) { \␊
572 if ((out)->hh.keylen == keylen_in) { \␊
573 if ((HASH_KEYCMP((out)->hh.key,keyptr,keylen_in)) == 0) break; \␊
574 } \␊
575 if ((out)->hh.hh_next) DECLTYPE_ASSIGN(out,ELMT_FROM_HH(tbl,(out)->hh.hh_next)); \␊
576 else out = NULL; \␊
577 } \␊
578} while(0)␊
579␊
580/* add an item to a bucket */␊
581#define HASH_ADD_TO_BKT(head,addhh) \␊
582do { \␊
583 head.count++; \␊
584 (addhh)->hh_next = head.hh_head; \␊
585 (addhh)->hh_prev = NULL; \␊
586 if (head.hh_head) { (head).hh_head->hh_prev = (addhh); } \␊
587 (head).hh_head=addhh; \␊
588 if (head.count >= ((head.expand_mult+1) * HASH_BKT_CAPACITY_THRESH) \␊
589 && (addhh)->tbl->noexpand != 1) { \␊
590 HASH_EXPAND_BUCKETS((addhh)->tbl); \␊
591 } \␊
592} while(0)␊
593␊
594/* remove an item from a given bucket */␊
595#define HASH_DEL_IN_BKT(hh,head,hh_del) \␊
596 (head).count--; \␊
597 if ((head).hh_head == hh_del) { \␊
598 (head).hh_head = hh_del->hh_next; \␊
599 } \␊
600 if (hh_del->hh_prev) { \␊
601 hh_del->hh_prev->hh_next = hh_del->hh_next; \␊
602 } \␊
603 if (hh_del->hh_next) { \␊
604 hh_del->hh_next->hh_prev = hh_del->hh_prev; \␊
605 } ␊
606␊
607/* Bucket expansion has the effect of doubling the number of buckets␊
608 * and redistributing the items into the new buckets. Ideally the␊
609 * items will distribute more or less evenly into the new buckets␊
610 * (the extent to which this is true is a measure of the quality of␊
611 * the hash function as it applies to the key domain). ␊
612 * ␊
613 * With the items distributed into more buckets, the chain length␊
614 * (item count) in each bucket is reduced. Thus by expanding buckets␊
615 * the hash keeps a bound on the chain length. This bounded chain ␊
616 * length is the essence of how a hash provides constant time lookup.␊
617 * ␊
618 * The calculation of tbl->ideal_chain_maxlen below deserves some␊
619 * explanation. First, keep in mind that we're calculating the ideal␊
620 * maximum chain length based on the *new* (doubled) bucket count.␊
621 * In fractions this is just n/b (n=number of items,b=new num buckets).␊
622 * Since the ideal chain length is an integer, we want to calculate ␊
623 * ceil(n/b). We don't depend on floating point arithmetic in this␊
624 * hash, so to calculate ceil(n/b) with integers we could write␊
625 * ␊
626 * ceil(n/b) = (n/b) + ((n%b)?1:0)␊
627 * ␊
628 * and in fact a previous version of this hash did just that.␊
629 * But now we have improved things a bit by recognizing that b is␊
630 * always a power of two. We keep its base 2 log handy (call it lb),␊
631 * so now we can write this with a bit shift and logical AND:␊
632 * ␊
633 * ceil(n/b) = (n>>lb) + ( (n & (b-1)) ? 1:0)␊
634 * ␊
635 */␊
636#define HASH_EXPAND_BUCKETS(tbl) \␊
637do { \␊
638 unsigned _he_bkt; \␊
639 unsigned _he_bkt_i; \␊
640 struct UT_hash_handle *_he_thh, *_he_hh_nxt; \␊
641 UT_hash_bucket *_he_new_buckets, *_he_newbkt; \␊
642 unsigned long _he_bkt_size = 2 * tbl->num_buckets \␊
643 * sizeof(struct UT_hash_bucket); \␊
644 if (!(_he_bkt_size > 0)) { uthash_fatal( "unknown error"); } \␊
645 _he_new_buckets = (UT_hash_bucket*)uthash_malloc(_he_bkt_size); \␊
646 if (!_he_new_buckets) { uthash_fatal( "out of memory"); } \␊
647 memset(_he_new_buckets, 0, \␊
648 2 * tbl->num_buckets * sizeof(struct UT_hash_bucket)); \␊
649 tbl->ideal_chain_maxlen = \␊
650 (tbl->num_items >> (tbl->log2_num_buckets+1)) + \␊
651 ((tbl->num_items & ((tbl->num_buckets*2)-1)) ? 1 : 0); \␊
652 tbl->nonideal_items = 0; \␊
653 for(_he_bkt_i = 0; _he_bkt_i < tbl->num_buckets; _he_bkt_i++) \␊
654 { \␊
655 _he_thh = tbl->buckets[ _he_bkt_i ].hh_head; \␊
656 while (_he_thh) { \␊
657 _he_hh_nxt = _he_thh->hh_next; \␊
658 HASH_TO_BKT( _he_thh->hashv, tbl->num_buckets*2, _he_bkt); \␊
659 _he_newbkt = &(_he_new_buckets[ _he_bkt ]); \␊
660 if (_he_newbkt) { \␊
661 if (++(_he_newbkt->count) > tbl->ideal_chain_maxlen) { \␊
662 tbl->nonideal_items++; \␊
663 _he_newbkt->expand_mult = _he_newbkt->count / \␊
664 tbl->ideal_chain_maxlen; \␊
665 } \␊
666 _he_thh->hh_prev = NULL; \␊
667 _he_thh->hh_next = _he_newbkt->hh_head; \␊
668 if (_he_newbkt->hh_head) _he_newbkt->hh_head->hh_prev = \␊
669 _he_thh; \␊
670 _he_newbkt->hh_head = _he_thh; \␊
671 _he_thh = _he_hh_nxt; \␊
672 } \␊
673 else { uthash_fatal( "out of memory"); } \␊
674 } \␊
675 } \␊
676 uthash_free( tbl->buckets, tbl->num_buckets*sizeof(struct UT_hash_bucket) ); \␊
677 tbl->num_buckets *= 2; \␊
678 tbl->log2_num_buckets++; \␊
679 tbl->buckets = _he_new_buckets; \␊
680 tbl->ineff_expands = (tbl->nonideal_items > (tbl->num_items >> 1)) ? \␊
681 (tbl->ineff_expands+1) : 0; \␊
682 if (tbl->ineff_expands > 1) { \␊
683 tbl->noexpand=1; \␊
684 uthash_noexpand_fyi(tbl); \␊
685 } \␊
686 uthash_expand_fyi(tbl); \␊
687} while(0)␊
688␊
689␊
690/* This is an adaptation of Simon Tatham's O(n log(n)) mergesort */␊
691/* Note that HASH_SORT assumes the hash handle name to be hh. ␊
692 * HASH_SRT was added to allow the hash handle name to be passed in. */␊
693#define HASH_SORT(head,cmpfcn) HASH_SRT(hh,head,cmpfcn)␊
694#define HASH_SRT(hh,head,cmpfcn) \␊
695do { \␊
696 unsigned _hs_i; \␊
697 unsigned _hs_looping,_hs_nmerges,_hs_insize,_hs_psize,_hs_qsize; \␊
698 struct UT_hash_handle *_hs_p, *_hs_q, *_hs_e, *_hs_list, *_hs_tail; \␊
699 if (head) { \␊
700 _hs_insize = 1; \␊
701 _hs_looping = 1; \␊
702 _hs_list = &((head)->hh); \␊
703 while (_hs_looping) { \␊
704 _hs_p = _hs_list; \␊
705 _hs_list = NULL; \␊
706 _hs_tail = NULL; \␊
707 _hs_nmerges = 0; \␊
708 while (_hs_p) { \␊
709 _hs_nmerges++; \␊
710 _hs_q = _hs_p; \␊
711 _hs_psize = 0; \␊
712 for ( _hs_i = 0; _hs_i < _hs_insize; _hs_i++ ) { \␊
713 _hs_psize++; \␊
714 _hs_q = (UT_hash_handle*)((_hs_q->next) ? \␊
715 ((void*)((char*)(_hs_q->next) + \␊
716 (head)->hh.tbl->hho)) : NULL); \␊
717 if (! (_hs_q) ) break; \␊
718 } \␊
719 _hs_qsize = _hs_insize; \␊
720 while ((_hs_psize > 0) || ((_hs_qsize > 0) && _hs_q )) { \␊
721 if (_hs_psize == 0) { \␊
722 _hs_e = _hs_q; \␊
723 _hs_q = (UT_hash_handle*)((_hs_q->next) ? \␊
724 ((void*)((char*)(_hs_q->next) + \␊
725 (head)->hh.tbl->hho)) : NULL); \␊
726 _hs_qsize--; \␊
727 } else if ( (_hs_qsize == 0) || !(_hs_q) ) { \␊
728 _hs_e = _hs_p; \␊
729 _hs_p = (UT_hash_handle*)((_hs_p->next) ? \␊
730 ((void*)((char*)(_hs_p->next) + \␊
731 (head)->hh.tbl->hho)) : NULL); \␊
732 _hs_psize--; \␊
733 } else if (( \␊
734 cmpfcn(DECLTYPE(head)(ELMT_FROM_HH((head)->hh.tbl,_hs_p)), \␊
735 DECLTYPE(head)(ELMT_FROM_HH((head)->hh.tbl,_hs_q))) \␊
736 ) <= 0) { \␊
737 _hs_e = _hs_p; \␊
738 _hs_p = (UT_hash_handle*)((_hs_p->next) ? \␊
739 ((void*)((char*)(_hs_p->next) + \␊
740 (head)->hh.tbl->hho)) : NULL); \␊
741 _hs_psize--; \␊
742 } else { \␊
743 _hs_e = _hs_q; \␊
744 _hs_q = (UT_hash_handle*)((_hs_q->next) ? \␊
745 ((void*)((char*)(_hs_q->next) + \␊
746 (head)->hh.tbl->hho)) : NULL); \␊
747 _hs_qsize--; \␊
748 } \␊
749 if ( _hs_tail ) { \␊
750 _hs_tail->next = ((_hs_e) ? \␊
751 ELMT_FROM_HH((head)->hh.tbl,_hs_e) : NULL); \␊
752 } else { \␊
753 _hs_list = _hs_e; \␊
754 } \␊
755 _hs_e->prev = ((_hs_tail) ? \␊
756 ELMT_FROM_HH((head)->hh.tbl,_hs_tail) : NULL); \␊
757 _hs_tail = _hs_e; \␊
758 } \␊
759 _hs_p = _hs_q; \␊
760 } \␊
761 _hs_tail->next = NULL; \␊
762 if ( _hs_nmerges <= 1 ) { \␊
763 _hs_looping=0; \␊
764 (head)->hh.tbl->tail = _hs_tail; \␊
765 DECLTYPE_ASSIGN(head,ELMT_FROM_HH((head)->hh.tbl, _hs_list)); \␊
766 } \␊
767 _hs_insize *= 2; \␊
768 } \␊
769 HASH_FSCK(hh,head); \␊
770 } \␊
771} while (0)␊
772␊
773/* This function selects items from one hash into another hash. ␊
774 * The end result is that the selected items have dual presence ␊
775 * in both hashes. There is no copy of the items made; rather ␊
776 * they are added into the new hash through a secondary hash ␊
777 * hash handle that must be present in the structure. */␊
778#define HASH_SELECT(hh_dst, dst, hh_src, src, cond) \␊
779do { \␊
780 unsigned _src_bkt, _dst_bkt; \␊
781 void *_last_elt=NULL, *_elt; \␊
782 UT_hash_handle *_src_hh, *_dst_hh, *_last_elt_hh=NULL; \␊
783 ptrdiff_t _dst_hho = ((char*)(&(dst)->hh_dst) - (char*)(dst)); \␊
784 if (src) { \␊
785 for(_src_bkt=0; _src_bkt < (src)->hh_src.tbl->num_buckets; _src_bkt++) { \␊
786 for(_src_hh = (src)->hh_src.tbl->buckets[_src_bkt].hh_head; \␊
787 _src_hh; \␊
788 _src_hh = _src_hh->hh_next) { \␊
789 _elt = ELMT_FROM_HH((src)->hh_src.tbl, _src_hh); \␊
790 if (cond(_elt)) { \␊
791 _dst_hh = (UT_hash_handle*)(((char*)_elt) + _dst_hho); \␊
792 _dst_hh->key = _src_hh->key; \␊
793 _dst_hh->keylen = _src_hh->keylen; \␊
794 _dst_hh->hashv = _src_hh->hashv; \␊
795 _dst_hh->prev = _last_elt; \␊
796 _dst_hh->next = NULL; \␊
797 if (_last_elt_hh) { _last_elt_hh->next = _elt; } \␊
798 if (!dst) { \␊
799 DECLTYPE_ASSIGN(dst,_elt); \␊
800 HASH_MAKE_TABLE(hh_dst,dst); \␊
801 } else { \␊
802 _dst_hh->tbl = (dst)->hh_dst.tbl; \␊
803 } \␊
804 HASH_TO_BKT(_dst_hh->hashv, _dst_hh->tbl->num_buckets, _dst_bkt); \␊
805 HASH_ADD_TO_BKT(_dst_hh->tbl->buckets[_dst_bkt],_dst_hh); \␊
806 (dst)->hh_dst.tbl->num_items++; \␊
807 _last_elt = _elt; \␊
808 _last_elt_hh = _dst_hh; \␊
809 } \␊
810 } \␊
811 } \␊
812 } \␊
813 HASH_FSCK(hh_dst,dst); \␊
814} while (0)␊
815␊
816#define HASH_CLEAR(hh,head) \␊
817do { \␊
818 if (head) { \␊
819 uthash_free((head)->hh.tbl->buckets, \␊
820 (head)->hh.tbl->num_buckets*sizeof(struct UT_hash_bucket)); \␊
821 HASH_BLOOM_FREE((head)->hh.tbl); \␊
822 uthash_free((head)->hh.tbl, sizeof(UT_hash_table)); \␊
823 (head)=NULL; \␊
824 } \␊
825} while(0)␊
826␊
827#ifdef NO_DECLTYPE␊
828#define HASH_ITER(hh,head,el,tmp) \␊
829for((el)=(head), (*(char**)(&(tmp)))=(char*)((head)?(head)->hh.next:NULL); \␊
830 el; (el)=(tmp),(*(char**)(&(tmp)))=(char*)((tmp)?(tmp)->hh.next:NULL)) ␊
831#else␊
832#define HASH_ITER(hh,head,el,tmp) \␊
833for((el)=(head),(tmp)=DECLTYPE(el)((head)?(head)->hh.next:NULL); \␊
834 el; (el)=(tmp),(tmp)=DECLTYPE(el)((tmp)?(tmp)->hh.next:NULL))␊
835#endif␊
836␊
837/* obtain a count of items in the hash */␊
838#define HASH_COUNT(head) HASH_CNT(hh,head) ␊
839#define HASH_CNT(hh,head) ((head)?((head)->hh.tbl->num_items):0)␊
840␊
841typedef struct UT_hash_bucket {␊
842 struct UT_hash_handle *hh_head;␊
843 unsigned count;␊
844␊
845 /* expand_mult is normally set to 0. In this situation, the max chain length␊
846 * threshold is enforced at its default value, HASH_BKT_CAPACITY_THRESH. (If␊
847 * the bucket's chain exceeds this length, bucket expansion is triggered). ␊
848 * However, setting expand_mult to a non-zero value delays bucket expansion␊
849 * (that would be triggered by additions to this particular bucket)␊
850 * until its chain length reaches a *multiple* of HASH_BKT_CAPACITY_THRESH.␊
851 * (The multiplier is simply expand_mult+1). The whole idea of this␊
852 * multiplier is to reduce bucket expansions, since they are expensive, in␊
853 * situations where we know that a particular bucket tends to be overused.␊
854 * It is better to let its chain length grow to a longer yet-still-bounded␊
855 * value, than to do an O(n) bucket expansion too often. ␊
856 */␊
857 unsigned expand_mult;␊
858␊
859} UT_hash_bucket;␊
860␊
861/* random signature used only to find hash tables in external analysis */␊
862#define HASH_SIGNATURE 0xa0111fe1␊
863#define HASH_BLOOM_SIGNATURE 0xb12220f2␊
864␊
865typedef struct UT_hash_table {␊
866 UT_hash_bucket *buckets;␊
867 unsigned num_buckets, log2_num_buckets;␊
868 unsigned num_items;␊
869 struct UT_hash_handle *tail; /* tail hh in app order, for fast append */␊
870 ptrdiff_t hho; /* hash handle offset (byte pos of hash handle in element */␊
871␊
872 /* in an ideal situation (all buckets used equally), no bucket would have␊
873 * more than ceil(#items/#buckets) items. that's the ideal chain length. */␊
874 unsigned ideal_chain_maxlen;␊
875␊
876 /* nonideal_items is the number of items in the hash whose chain position␊
877 * exceeds the ideal chain maxlen. these items pay the penalty for an uneven␊
878 * hash distribution; reaching them in a chain traversal takes >ideal steps */␊
879 unsigned nonideal_items;␊
880␊
881 /* ineffective expands occur when a bucket doubling was performed, but ␊
882 * afterward, more than half the items in the hash had nonideal chain␊
883 * positions. If this happens on two consecutive expansions we inhibit any␊
884 * further expansion, as it's not helping; this happens when the hash␊
885 * function isn't a good fit for the key domain. When expansion is inhibited␊
886 * the hash will still work, albeit no longer in constant time. */␊
887 unsigned ineff_expands, noexpand;␊
888␊
889 uint32_t signature; /* used only to find hash tables in external analysis */␊
890#ifdef HASH_BLOOM␊
891 uint32_t bloom_sig; /* used only to test bloom exists in external analysis */␊
892 uint8_t *bloom_bv;␊
893 char bloom_nbits;␊
894#endif␊
895␊
896} UT_hash_table;␊
897␊
898typedef struct UT_hash_handle {␊
899 struct UT_hash_table *tbl;␊
900 void *prev; /* prev element in app order */␊
901 void *next; /* next element in app order */␊
902 struct UT_hash_handle *hh_prev; /* previous hh in bucket order */␊
903 struct UT_hash_handle *hh_next; /* next hh in bucket order */␊
904 void *key; /* ptr to enclosing struct's key */␊
905 unsigned keylen; /* enclosing struct's key len */␊
906 unsigned hashv; /* result of hash-fcn(key) */␊
907} UT_hash_handle;␊
908␊
909#endif /* UTHASH_H */␊
910

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