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uthash.h (62067B)


      1 /*
      2 Copyright (c) 2003-2014, Troy D. Hanson     http://troydhanson.github.com/uthash/
      3 All rights reserved.
      4 
      5 Redistribution and use in source and binary forms, with or without
      6 modification, 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 
     11 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
     12 IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     13 TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
     14 PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
     15 OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
     16 EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
     17 PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
     18 PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
     19 LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
     20 NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
     21 SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     22 */
     23 
     24 #ifndef UTHASH_H
     25 #define UTHASH_H
     26 
     27 #include <string.h>   /* memcmp,strlen */
     28 #include <stddef.h>   /* ptrdiff_t */
     29 #include <stdlib.h>   /* exit() */
     30 
     31 /* These macros use decltype or the earlier __typeof GNU extension.
     32    As decltype is only available in newer compilers (VS2010 or gcc 4.3+
     33    when compiling c++ source) this code uses whatever method is needed
     34    or, for VS2008 where neither is available, uses casting workarounds. */
     35 #if defined(_MSC_VER)   /* MS compiler */
     36 #if _MSC_VER >= 1600 && defined(__cplusplus)  /* VS2010 or newer in C++ mode */
     37 #define DECLTYPE(x) (decltype(x))
     38 #else                   /* VS2008 or older (or VS2010 in C mode) */
     39 #define NO_DECLTYPE
     40 #define DECLTYPE(x)
     41 #endif
     42 #elif defined(__BORLANDC__) || defined(__LCC__) || defined(__WATCOMC__)
     43 #define NO_DECLTYPE
     44 #define DECLTYPE(x)
     45 #else                   /* GNU, Sun and other compilers */
     46 #define DECLTYPE(x) (__typeof(x))
     47 #endif
     48 
     49 #ifdef NO_DECLTYPE
     50 #define DECLTYPE_ASSIGN(dst,src)                                                 \
     51 do {                                                                             \
     52   char **_da_dst = (char**)(&(dst));                                             \
     53   *_da_dst = (char*)(src);                                                       \
     54 } while(0)
     55 #else
     56 #define DECLTYPE_ASSIGN(dst,src)                                                 \
     57 do {                                                                             \
     58   (dst) = DECLTYPE(dst)(src);                                                    \
     59 } while(0)
     60 #endif
     61 
     62 /* a number of the hash function use uint32_t which isn't defined on Pre VS2010 */
     63 #if defined (_WIN32)
     64 #if defined(_MSC_VER) && _MSC_VER >= 1600
     65 #include <stdint.h>
     66 #elif defined(__WATCOMC__)
     67 #include <stdint.h>
     68 #else
     69 typedef unsigned int uint32_t;
     70 typedef unsigned char uint8_t;
     71 #endif
     72 #else
     73 #include <stdint.h>
     74 #endif
     75 
     76 #define UTHASH_VERSION 1.9.9
     77 
     78 #ifndef uthash_fatal
     79 #define uthash_fatal(msg) exit(-1)        /* fatal error (out of memory,etc) */
     80 #endif
     81 #ifndef uthash_malloc
     82 #define uthash_malloc(sz) malloc(sz)      /* malloc fcn                      */
     83 #endif
     84 #ifndef uthash_free
     85 #define uthash_free(ptr,sz) free(ptr)     /* free fcn                        */
     86 #endif
     87 
     88 #ifndef uthash_noexpand_fyi
     89 #define uthash_noexpand_fyi(tbl)          /* can be defined to log noexpand  */
     90 #endif
     91 #ifndef uthash_expand_fyi
     92 #define uthash_expand_fyi(tbl)            /* can be defined to log expands   */
     93 #endif
     94 
     95 /* initial number of buckets */
     96 #define HASH_INITIAL_NUM_BUCKETS 32U     /* initial number of buckets        */
     97 #define HASH_INITIAL_NUM_BUCKETS_LOG2 5U /* lg2 of initial number of buckets */
     98 #define HASH_BKT_CAPACITY_THRESH 10U     /* expand when bucket count reaches */
     99 
    100 /* calculate the element whose hash handle address is hhe */
    101 #define ELMT_FROM_HH(tbl,hhp) ((void*)(((char*)(hhp)) - ((tbl)->hho)))
    102 
    103 #define HASH_FIND(hh,head,keyptr,keylen,out)                                     \
    104 do {                                                                             \
    105   out=NULL;                                                                      \
    106   if (head != NULL) {                                                            \
    107      unsigned _hf_bkt,_hf_hashv;                                                 \
    108      HASH_FCN(keyptr,keylen, (head)->hh.tbl->num_buckets, _hf_hashv, _hf_bkt);   \
    109      if (HASH_BLOOM_TEST((head)->hh.tbl, _hf_hashv) != 0) {                      \
    110        HASH_FIND_IN_BKT((head)->hh.tbl, hh, (head)->hh.tbl->buckets[ _hf_bkt ],  \
    111                         keyptr,keylen,out);                                      \
    112      }                                                                           \
    113   }                                                                              \
    114 } while (0)
    115 
    116 #ifdef HASH_BLOOM
    117 #define HASH_BLOOM_BITLEN (1UL << HASH_BLOOM)
    118 #define HASH_BLOOM_BYTELEN (HASH_BLOOM_BITLEN/8UL) + (((HASH_BLOOM_BITLEN%8UL)!=0UL) ? 1UL : 0UL)
    119 #define HASH_BLOOM_MAKE(tbl)                                                     \
    120 do {                                                                             \
    121   (tbl)->bloom_nbits = HASH_BLOOM;                                               \
    122   (tbl)->bloom_bv = (uint8_t*)uthash_malloc(HASH_BLOOM_BYTELEN);                 \
    123   if (!((tbl)->bloom_bv))  { uthash_fatal( "out of memory"); }                   \
    124   memset((tbl)->bloom_bv, 0, HASH_BLOOM_BYTELEN);                                \
    125   (tbl)->bloom_sig = HASH_BLOOM_SIGNATURE;                                       \
    126 } while (0)
    127 
    128 #define HASH_BLOOM_FREE(tbl)                                                     \
    129 do {                                                                             \
    130   uthash_free((tbl)->bloom_bv, HASH_BLOOM_BYTELEN);                              \
    131 } while (0)
    132 
    133 #define HASH_BLOOM_BITSET(bv,idx) (bv[(idx)/8U] |= (1U << ((idx)%8U)))
    134 #define HASH_BLOOM_BITTEST(bv,idx) (bv[(idx)/8U] & (1U << ((idx)%8U)))
    135 
    136 #define HASH_BLOOM_ADD(tbl,hashv)                                                \
    137   HASH_BLOOM_BITSET((tbl)->bloom_bv, (hashv & (uint32_t)((1ULL << (tbl)->bloom_nbits) - 1U)))
    138 
    139 #define HASH_BLOOM_TEST(tbl,hashv)                                               \
    140   HASH_BLOOM_BITTEST((tbl)->bloom_bv, (hashv & (uint32_t)((1ULL << (tbl)->bloom_nbits) - 1U)))
    141 
    142 #else
    143 #define HASH_BLOOM_MAKE(tbl)
    144 #define HASH_BLOOM_FREE(tbl)
    145 #define HASH_BLOOM_ADD(tbl,hashv)
    146 #define HASH_BLOOM_TEST(tbl,hashv) (1)
    147 #define HASH_BLOOM_BYTELEN 0U
    148 #endif
    149 
    150 #define HASH_MAKE_TABLE(hh,head)                                                 \
    151 do {                                                                             \
    152   (head)->hh.tbl = (UT_hash_table*)uthash_malloc(                                \
    153                   sizeof(UT_hash_table));                                        \
    154   if (!((head)->hh.tbl))  { uthash_fatal( "out of memory"); }                    \
    155   memset((head)->hh.tbl, 0, sizeof(UT_hash_table));                              \
    156   (head)->hh.tbl->tail = &((head)->hh);                                          \
    157   (head)->hh.tbl->num_buckets = HASH_INITIAL_NUM_BUCKETS;                        \
    158   (head)->hh.tbl->log2_num_buckets = HASH_INITIAL_NUM_BUCKETS_LOG2;              \
    159   (head)->hh.tbl->hho = (char*)(&(head)->hh) - (char*)(head);                    \
    160   (head)->hh.tbl->buckets = (UT_hash_bucket*)uthash_malloc(                      \
    161           HASH_INITIAL_NUM_BUCKETS*sizeof(struct UT_hash_bucket));               \
    162   if (! (head)->hh.tbl->buckets) { uthash_fatal( "out of memory"); }             \
    163   memset((head)->hh.tbl->buckets, 0,                                             \
    164           HASH_INITIAL_NUM_BUCKETS*sizeof(struct UT_hash_bucket));               \
    165   HASH_BLOOM_MAKE((head)->hh.tbl);                                               \
    166   (head)->hh.tbl->signature = HASH_SIGNATURE;                                    \
    167 } while(0)
    168 
    169 #define HASH_ADD(hh,head,fieldname,keylen_in,add)                                \
    170         HASH_ADD_KEYPTR(hh,head,&((add)->fieldname),keylen_in,add)
    171 
    172 #define HASH_REPLACE(hh,head,fieldname,keylen_in,add,replaced)                   \
    173 do {                                                                             \
    174   replaced=NULL;                                                                 \
    175   HASH_FIND(hh,head,&((add)->fieldname),keylen_in,replaced);                     \
    176   if (replaced!=NULL) {                                                          \
    177      HASH_DELETE(hh,head,replaced);                                              \
    178   }                                                                              \
    179   HASH_ADD(hh,head,fieldname,keylen_in,add);                                     \
    180 } while(0)
    181 
    182 #define HASH_ADD_KEYPTR(hh,head,keyptr,keylen_in,add)                            \
    183 do {                                                                             \
    184  unsigned _ha_bkt;                                                               \
    185  (add)->hh.next = NULL;                                                          \
    186  (add)->hh.key = (char*)(keyptr);                                                \
    187  (add)->hh.keylen = (unsigned)(keylen_in);                                       \
    188  if (!(head)) {                                                                  \
    189     head = (add);                                                                \
    190     (head)->hh.prev = NULL;                                                      \
    191     HASH_MAKE_TABLE(hh,head);                                                    \
    192  } else {                                                                        \
    193     (head)->hh.tbl->tail->next = (add);                                          \
    194     (add)->hh.prev = ELMT_FROM_HH((head)->hh.tbl, (head)->hh.tbl->tail);         \
    195     (head)->hh.tbl->tail = &((add)->hh);                                         \
    196  }                                                                               \
    197  (head)->hh.tbl->num_items++;                                                    \
    198  (add)->hh.tbl = (head)->hh.tbl;                                                 \
    199  HASH_FCN(keyptr,keylen_in, (head)->hh.tbl->num_buckets,                         \
    200          (add)->hh.hashv, _ha_bkt);                                              \
    201  HASH_ADD_TO_BKT((head)->hh.tbl->buckets[_ha_bkt],&(add)->hh);                   \
    202  HASH_BLOOM_ADD((head)->hh.tbl,(add)->hh.hashv);                                 \
    203  HASH_EMIT_KEY(hh,head,keyptr,keylen_in);                                        \
    204  HASH_FSCK(hh,head);                                                             \
    205 } while(0)
    206 
    207 #define HASH_TO_BKT( hashv, num_bkts, bkt )                                      \
    208 do {                                                                             \
    209   bkt = ((hashv) & ((num_bkts) - 1U));                                           \
    210 } while(0)
    211 
    212 /* delete "delptr" from the hash table.
    213  * "the usual" patch-up process for the app-order doubly-linked-list.
    214  * The use of _hd_hh_del below deserves special explanation.
    215  * These used to be expressed using (delptr) but that led to a bug
    216  * if someone used the same symbol for the head and deletee, like
    217  *  HASH_DELETE(hh,users,users);
    218  * We want that to work, but by changing the head (users) below
    219  * we were forfeiting our ability to further refer to the deletee (users)
    220  * in the patch-up process. Solution: use scratch space to
    221  * copy the deletee pointer, then the latter references are via that
    222  * scratch pointer rather than through the repointed (users) symbol.
    223  */
    224 #define HASH_DELETE(hh,head,delptr)                                              \
    225 do {                                                                             \
    226     struct UT_hash_handle *_hd_hh_del;                                           \
    227     if ( ((delptr)->hh.prev == NULL) && ((delptr)->hh.next == NULL) )  {         \
    228         uthash_free((head)->hh.tbl->buckets,                                     \
    229                     (head)->hh.tbl->num_buckets*sizeof(struct UT_hash_bucket) ); \
    230         HASH_BLOOM_FREE((head)->hh.tbl);                                         \
    231         uthash_free((head)->hh.tbl, sizeof(UT_hash_table));                      \
    232         head = NULL;                                                             \
    233     } else {                                                                     \
    234         unsigned _hd_bkt;                                                        \
    235         _hd_hh_del = &((delptr)->hh);                                            \
    236         if ((delptr) == ELMT_FROM_HH((head)->hh.tbl,(head)->hh.tbl->tail)) {     \
    237             (head)->hh.tbl->tail =                                               \
    238                 (UT_hash_handle*)((ptrdiff_t)((delptr)->hh.prev) +               \
    239                 (head)->hh.tbl->hho);                                            \
    240         }                                                                        \
    241         if ((delptr)->hh.prev != NULL) {                                         \
    242             ((UT_hash_handle*)((ptrdiff_t)((delptr)->hh.prev) +                  \
    243                     (head)->hh.tbl->hho))->next = (delptr)->hh.next;             \
    244         } else {                                                                 \
    245             DECLTYPE_ASSIGN(head,(delptr)->hh.next);                             \
    246         }                                                                        \
    247         if (_hd_hh_del->next != NULL) {                                          \
    248             ((UT_hash_handle*)((ptrdiff_t)_hd_hh_del->next +                     \
    249                     (head)->hh.tbl->hho))->prev =                                \
    250                     _hd_hh_del->prev;                                            \
    251         }                                                                        \
    252         HASH_TO_BKT( _hd_hh_del->hashv, (head)->hh.tbl->num_buckets, _hd_bkt);   \
    253         HASH_DEL_IN_BKT(hh,(head)->hh.tbl->buckets[_hd_bkt], _hd_hh_del);        \
    254         (head)->hh.tbl->num_items--;                                             \
    255     }                                                                            \
    256     HASH_FSCK(hh,head);                                                          \
    257 } while (0)
    258 
    259 
    260 /* convenience forms of HASH_FIND/HASH_ADD/HASH_DEL */
    261 #define HASH_FIND_STR(head,findstr,out)                                          \
    262     HASH_FIND(hh,head,findstr,(unsigned)strlen(findstr),out)
    263 #define HASH_ADD_STR(head,strfield,add)                                          \
    264     HASH_ADD(hh,head,strfield[0],(unsigned int)strlen(add->strfield),add)
    265 #define HASH_REPLACE_STR(head,strfield,add,replaced)                             \
    266     HASH_REPLACE(hh,head,strfield[0],(unsigned)strlen(add->strfield),add,replaced)
    267 #define HASH_FIND_INT(head,findint,out)                                          \
    268     HASH_FIND(hh,head,findint,sizeof(int),out)
    269 #define HASH_ADD_INT(head,intfield,add)                                          \
    270     HASH_ADD(hh,head,intfield,sizeof(int),add)
    271 #define HASH_REPLACE_INT(head,intfield,add,replaced)                             \
    272     HASH_REPLACE(hh,head,intfield,sizeof(int),add,replaced)
    273 #define HASH_FIND_PTR(head,findptr,out)                                          \
    274     HASH_FIND(hh,head,findptr,sizeof(void *),out)
    275 #define HASH_ADD_PTR(head,ptrfield,add)                                          \
    276     HASH_ADD(hh,head,ptrfield,sizeof(void *),add)
    277 #define HASH_REPLACE_PTR(head,ptrfield,add,replaced)                             \
    278     HASH_REPLACE(hh,head,ptrfield,sizeof(void *),add,replaced)
    279 #define HASH_DEL(head,delptr)                                                    \
    280     HASH_DELETE(hh,head,delptr)
    281 
    282 /* HASH_FSCK checks hash integrity on every add/delete when HASH_DEBUG is defined.
    283  * This is for uthash developer only; it compiles away if HASH_DEBUG isn't defined.
    284  */
    285 #ifdef HASH_DEBUG
    286 #define HASH_OOPS(...) do { fprintf(stderr,__VA_ARGS__); exit(-1); } while (0)
    287 #define HASH_FSCK(hh,head)                                                       \
    288 do {                                                                             \
    289     struct UT_hash_handle *_thh;                                                 \
    290     if (head) {                                                                  \
    291         unsigned _bkt_i;                                                         \
    292         unsigned _count;                                                         \
    293         char *_prev;                                                             \
    294         _count = 0;                                                              \
    295         for( _bkt_i = 0; _bkt_i < (head)->hh.tbl->num_buckets; _bkt_i++) {       \
    296             unsigned _bkt_count = 0;                                             \
    297             _thh = (head)->hh.tbl->buckets[_bkt_i].hh_head;                      \
    298             _prev = NULL;                                                        \
    299             while (_thh) {                                                       \
    300                if (_prev != (char*)(_thh->hh_prev)) {                            \
    301                    HASH_OOPS("invalid hh_prev %p, actual %p\n",                  \
    302                     _thh->hh_prev, _prev );                                      \
    303                }                                                                 \
    304                _bkt_count++;                                                     \
    305                _prev = (char*)(_thh);                                            \
    306                _thh = _thh->hh_next;                                             \
    307             }                                                                    \
    308             _count += _bkt_count;                                                \
    309             if ((head)->hh.tbl->buckets[_bkt_i].count !=  _bkt_count) {          \
    310                HASH_OOPS("invalid bucket count %u, actual %u\n",                 \
    311                 (head)->hh.tbl->buckets[_bkt_i].count, _bkt_count);              \
    312             }                                                                    \
    313         }                                                                        \
    314         if (_count != (head)->hh.tbl->num_items) {                               \
    315             HASH_OOPS("invalid hh item count %u, actual %u\n",                   \
    316                 (head)->hh.tbl->num_items, _count );                             \
    317         }                                                                        \
    318         /* traverse hh in app order; check next/prev integrity, count */         \
    319         _count = 0;                                                              \
    320         _prev = NULL;                                                            \
    321         _thh =  &(head)->hh;                                                     \
    322         while (_thh) {                                                           \
    323            _count++;                                                             \
    324            if (_prev !=(char*)(_thh->prev)) {                                    \
    325               HASH_OOPS("invalid prev %p, actual %p\n",                          \
    326                     _thh->prev, _prev );                                         \
    327            }                                                                     \
    328            _prev = (char*)ELMT_FROM_HH((head)->hh.tbl, _thh);                    \
    329            _thh = ( _thh->next ?  (UT_hash_handle*)((char*)(_thh->next) +        \
    330                                   (head)->hh.tbl->hho) : NULL );                 \
    331         }                                                                        \
    332         if (_count != (head)->hh.tbl->num_items) {                               \
    333             HASH_OOPS("invalid app item count %u, actual %u\n",                  \
    334                 (head)->hh.tbl->num_items, _count );                             \
    335         }                                                                        \
    336     }                                                                            \
    337 } while (0)
    338 #else
    339 #define HASH_FSCK(hh,head)
    340 #endif
    341 
    342 /* When compiled with -DHASH_EMIT_KEYS, length-prefixed keys are emitted to
    343  * the descriptor to which this macro is defined for tuning the hash function.
    344  * The app can #include <unistd.h> to get the prototype for write(2). */
    345 #ifdef HASH_EMIT_KEYS
    346 #define HASH_EMIT_KEY(hh,head,keyptr,fieldlen)                                   \
    347 do {                                                                             \
    348     unsigned _klen = fieldlen;                                                   \
    349     write(HASH_EMIT_KEYS, &_klen, sizeof(_klen));                                \
    350     write(HASH_EMIT_KEYS, keyptr, (unsigned long)fieldlen);                      \
    351 } while (0)
    352 #else
    353 #define HASH_EMIT_KEY(hh,head,keyptr,fieldlen)
    354 #endif
    355 
    356 /* default to Jenkin's hash unless overridden e.g. DHASH_FUNCTION=HASH_SAX */
    357 #ifdef HASH_FUNCTION
    358 #define HASH_FCN HASH_FUNCTION
    359 #else
    360 #define HASH_FCN HASH_JEN
    361 #endif
    362 
    363 /* The Bernstein hash function, used in Perl prior to v5.6. Note (x<<5+x)=x*33. */
    364 #define HASH_BER(key,keylen,num_bkts,hashv,bkt)                                  \
    365 do {                                                                             \
    366   unsigned _hb_keylen=(unsigned)keylen;                                          \
    367   const unsigned char *_hb_key=(const unsigned char*)(key);                      \
    368   (hashv) = 0;                                                                   \
    369   while (_hb_keylen-- != 0U) {                                                   \
    370       (hashv) = (((hashv) << 5) + (hashv)) + *_hb_key++;                         \
    371   }                                                                              \
    372   bkt = (hashv) & (num_bkts-1U);                                                 \
    373 } while (0)
    374 
    375 
    376 /* SAX/FNV/OAT/JEN hash functions are macro variants of those listed at
    377  * http://eternallyconfuzzled.com/tuts/algorithms/jsw_tut_hashing.aspx */
    378 #define HASH_SAX(key,keylen,num_bkts,hashv,bkt)                                  \
    379 do {                                                                             \
    380   unsigned _sx_i;                                                                \
    381   const unsigned char *_hs_key=(const unsigned char*)(key);                      \
    382   hashv = 0;                                                                     \
    383   for(_sx_i=0; _sx_i < keylen; _sx_i++) {                                        \
    384       hashv ^= (hashv << 5) + (hashv >> 2) + _hs_key[_sx_i];                     \
    385   }                                                                              \
    386   bkt = hashv & (num_bkts-1U);                                                   \
    387 } while (0)
    388 /* FNV-1a variation */
    389 #define HASH_FNV(key,keylen,num_bkts,hashv,bkt)                                  \
    390 do {                                                                             \
    391   unsigned _fn_i;                                                                \
    392   const unsigned char *_hf_key=(const unsigned char*)(key);                      \
    393   hashv = 2166136261U;                                                           \
    394   for(_fn_i=0; _fn_i < keylen; _fn_i++) {                                        \
    395       hashv = hashv ^ _hf_key[_fn_i];                                            \
    396       hashv = hashv * 16777619U;                                                 \
    397   }                                                                              \
    398   bkt = hashv & (num_bkts-1U);                                                   \
    399 } while(0)
    400 
    401 #define HASH_OAT(key,keylen,num_bkts,hashv,bkt)                                  \
    402 do {                                                                             \
    403   unsigned _ho_i;                                                                \
    404   const unsigned char *_ho_key=(const unsigned char*)(key);                      \
    405   hashv = 0;                                                                     \
    406   for(_ho_i=0; _ho_i < keylen; _ho_i++) {                                        \
    407       hashv += _ho_key[_ho_i];                                                   \
    408       hashv += (hashv << 10);                                                    \
    409       hashv ^= (hashv >> 6);                                                     \
    410   }                                                                              \
    411   hashv += (hashv << 3);                                                         \
    412   hashv ^= (hashv >> 11);                                                        \
    413   hashv += (hashv << 15);                                                        \
    414   bkt = hashv & (num_bkts-1U);                                                   \
    415 } while(0)
    416 
    417 #define HASH_JEN_MIX(a,b,c)                                                      \
    418 do {                                                                             \
    419   a -= b; a -= c; a ^= ( c >> 13 );                                              \
    420   b -= c; b -= a; b ^= ( a << 8 );                                               \
    421   c -= a; c -= b; c ^= ( b >> 13 );                                              \
    422   a -= b; a -= c; a ^= ( c >> 12 );                                              \
    423   b -= c; b -= a; b ^= ( a << 16 );                                              \
    424   c -= a; c -= b; c ^= ( b >> 5 );                                               \
    425   a -= b; a -= c; a ^= ( c >> 3 );                                               \
    426   b -= c; b -= a; b ^= ( a << 10 );                                              \
    427   c -= a; c -= b; c ^= ( b >> 15 );                                              \
    428 } while (0)
    429 
    430 #define HASH_JEN(key,keylen,num_bkts,hashv,bkt)                                  \
    431 do {                                                                             \
    432   unsigned _hj_i,_hj_j,_hj_k;                                                    \
    433   unsigned const char *_hj_key=(unsigned const char*)(key);                      \
    434   hashv = 0xfeedbeefu;                                                           \
    435   _hj_i = _hj_j = 0x9e3779b9u;                                                   \
    436   _hj_k = (unsigned)(keylen);                                                    \
    437   while (_hj_k >= 12U) {                                                         \
    438     _hj_i +=    (_hj_key[0] + ( (unsigned)_hj_key[1] << 8 )                      \
    439         + ( (unsigned)_hj_key[2] << 16 )                                         \
    440         + ( (unsigned)_hj_key[3] << 24 ) );                                      \
    441     _hj_j +=    (_hj_key[4] + ( (unsigned)_hj_key[5] << 8 )                      \
    442         + ( (unsigned)_hj_key[6] << 16 )                                         \
    443         + ( (unsigned)_hj_key[7] << 24 ) );                                      \
    444     hashv += (_hj_key[8] + ( (unsigned)_hj_key[9] << 8 )                         \
    445         + ( (unsigned)_hj_key[10] << 16 )                                        \
    446         + ( (unsigned)_hj_key[11] << 24 ) );                                     \
    447                                                                                  \
    448      HASH_JEN_MIX(_hj_i, _hj_j, hashv);                                          \
    449                                                                                  \
    450      _hj_key += 12;                                                              \
    451      _hj_k -= 12U;                                                               \
    452   }                                                                              \
    453   hashv += (unsigned)(keylen);                                                   \
    454   switch ( _hj_k ) {                                                             \
    455      case 11: hashv += ( (unsigned)_hj_key[10] << 24 ); /* FALLTHROUGH */        \
    456      case 10: hashv += ( (unsigned)_hj_key[9] << 16 );  /* FALLTHROUGH */        \
    457      case 9:  hashv += ( (unsigned)_hj_key[8] << 8 );   /* FALLTHROUGH */        \
    458      case 8:  _hj_j += ( (unsigned)_hj_key[7] << 24 );  /* FALLTHROUGH */        \
    459      case 7:  _hj_j += ( (unsigned)_hj_key[6] << 16 );  /* FALLTHROUGH */        \
    460      case 6:  _hj_j += ( (unsigned)_hj_key[5] << 8 );   /* FALLTHROUGH */        \
    461      case 5:  _hj_j += _hj_key[4];                      /* FALLTHROUGH */        \
    462      case 4:  _hj_i += ( (unsigned)_hj_key[3] << 24 );  /* FALLTHROUGH */        \
    463      case 3:  _hj_i += ( (unsigned)_hj_key[2] << 16 );  /* FALLTHROUGH */        \
    464      case 2:  _hj_i += ( (unsigned)_hj_key[1] << 8 );   /* FALLTHROUGH */        \
    465      case 1:  _hj_i += _hj_key[0];                                               \
    466   }                                                                              \
    467   HASH_JEN_MIX(_hj_i, _hj_j, hashv);                                             \
    468   bkt = hashv & (num_bkts-1U);                                                   \
    469 } while(0)
    470 
    471 /* The Paul Hsieh hash function */
    472 #undef get16bits
    473 #if (defined(__GNUC__) && defined(__i386__)) || defined(__WATCOMC__)             \
    474   || defined(_MSC_VER) || defined (__BORLANDC__) || defined (__TURBOC__)
    475 #define get16bits(d) (*((const uint16_t *) (d)))
    476 #endif
    477 
    478 #if !defined (get16bits)
    479 #define get16bits(d) ((((uint32_t)(((const uint8_t *)(d))[1])) << 8)             \
    480                        +(uint32_t)(((const uint8_t *)(d))[0]) )
    481 #endif
    482 #define HASH_SFH(key,keylen,num_bkts,hashv,bkt)                                  \
    483 do {                                                                             \
    484   unsigned const char *_sfh_key=(unsigned const char*)(key);                     \
    485   uint32_t _sfh_tmp, _sfh_len = (uint32_t)keylen;                                \
    486                                                                                  \
    487   unsigned _sfh_rem = _sfh_len & 3U;                                             \
    488   _sfh_len >>= 2;                                                                \
    489   hashv = 0xcafebabeu;                                                           \
    490                                                                                  \
    491   /* Main loop */                                                                \
    492   for (;_sfh_len > 0U; _sfh_len--) {                                             \
    493     hashv    += get16bits (_sfh_key);                                            \
    494     _sfh_tmp  = ((uint32_t)(get16bits (_sfh_key+2)) << 11) ^ hashv;              \
    495     hashv     = (hashv << 16) ^ _sfh_tmp;                                        \
    496     _sfh_key += 2U*sizeof (uint16_t);                                            \
    497     hashv    += hashv >> 11;                                                     \
    498   }                                                                              \
    499                                                                                  \
    500   /* Handle end cases */                                                         \
    501   switch (_sfh_rem) {                                                            \
    502     case 3: hashv += get16bits (_sfh_key);                                       \
    503             hashv ^= hashv << 16;                                                \
    504             hashv ^= (uint32_t)(_sfh_key[sizeof (uint16_t)]) << 18;              \
    505             hashv += hashv >> 11;                                                \
    506             break;                                                               \
    507     case 2: hashv += get16bits (_sfh_key);                                       \
    508             hashv ^= hashv << 11;                                                \
    509             hashv += hashv >> 17;                                                \
    510             break;                                                               \
    511     case 1: hashv += *_sfh_key;                                                  \
    512             hashv ^= hashv << 10;                                                \
    513             hashv += hashv >> 1;                                                 \
    514   }                                                                              \
    515                                                                                  \
    516     /* Force "avalanching" of final 127 bits */                                  \
    517     hashv ^= hashv << 3;                                                         \
    518     hashv += hashv >> 5;                                                         \
    519     hashv ^= hashv << 4;                                                         \
    520     hashv += hashv >> 17;                                                        \
    521     hashv ^= hashv << 25;                                                        \
    522     hashv += hashv >> 6;                                                         \
    523     bkt = hashv & (num_bkts-1U);                                                 \
    524 } while(0)
    525 
    526 #ifdef HASH_USING_NO_STRICT_ALIASING
    527 /* The MurmurHash exploits some CPU's (x86,x86_64) tolerance for unaligned reads.
    528  * For other types of CPU's (e.g. Sparc) an unaligned read causes a bus error.
    529  * MurmurHash uses the faster approach only on CPU's where we know it's safe.
    530  *
    531  * Note the preprocessor built-in defines can be emitted using:
    532  *
    533  *   gcc -m64 -dM -E - < /dev/null                  (on gcc)
    534  *   cc -## a.c (where a.c is a simple test file)   (Sun Studio)
    535  */
    536 #if (defined(__i386__) || defined(__x86_64__)  || defined(_M_IX86))
    537 #define MUR_GETBLOCK(p,i) p[i]
    538 #else /* non intel */
    539 #define MUR_PLUS0_ALIGNED(p) (((unsigned long)p & 3UL) == 0UL)
    540 #define MUR_PLUS1_ALIGNED(p) (((unsigned long)p & 3UL) == 1UL)
    541 #define MUR_PLUS2_ALIGNED(p) (((unsigned long)p & 3UL) == 2UL)
    542 #define MUR_PLUS3_ALIGNED(p) (((unsigned long)p & 3UL) == 3UL)
    543 #define WP(p) ((uint32_t*)((unsigned long)(p) & ~3UL))
    544 #if (defined(__BIG_ENDIAN__) || defined(SPARC) || defined(__ppc__) || defined(__ppc64__))
    545 #define MUR_THREE_ONE(p) ((((*WP(p))&0x00ffffff) << 8) | (((*(WP(p)+1))&0xff000000) >> 24))
    546 #define MUR_TWO_TWO(p)   ((((*WP(p))&0x0000ffff) <<16) | (((*(WP(p)+1))&0xffff0000) >> 16))
    547 #define MUR_ONE_THREE(p) ((((*WP(p))&0x000000ff) <<24) | (((*(WP(p)+1))&0xffffff00) >>  8))
    548 #else /* assume little endian non-intel */
    549 #define MUR_THREE_ONE(p) ((((*WP(p))&0xffffff00) >> 8) | (((*(WP(p)+1))&0x000000ff) << 24))
    550 #define MUR_TWO_TWO(p)   ((((*WP(p))&0xffff0000) >>16) | (((*(WP(p)+1))&0x0000ffff) << 16))
    551 #define MUR_ONE_THREE(p) ((((*WP(p))&0xff000000) >>24) | (((*(WP(p)+1))&0x00ffffff) <<  8))
    552 #endif
    553 #define MUR_GETBLOCK(p,i) (MUR_PLUS0_ALIGNED(p) ? ((p)[i]) :           \
    554                             (MUR_PLUS1_ALIGNED(p) ? MUR_THREE_ONE(p) : \
    555                              (MUR_PLUS2_ALIGNED(p) ? MUR_TWO_TWO(p) :  \
    556                                                       MUR_ONE_THREE(p))))
    557 #endif
    558 #define MUR_ROTL32(x,r) (((x) << (r)) | ((x) >> (32 - (r))))
    559 #define MUR_FMIX(_h) \
    560 do {                 \
    561   _h ^= _h >> 16;    \
    562   _h *= 0x85ebca6bu; \
    563   _h ^= _h >> 13;    \
    564   _h *= 0xc2b2ae35u; \
    565   _h ^= _h >> 16;    \
    566 } while(0)
    567 
    568 #define HASH_MUR(key,keylen,num_bkts,hashv,bkt)                        \
    569 do {                                                                   \
    570   const uint8_t *_mur_data = (const uint8_t*)(key);                    \
    571   const int _mur_nblocks = (int)(keylen) / 4;                          \
    572   uint32_t _mur_h1 = 0xf88D5353u;                                      \
    573   uint32_t _mur_c1 = 0xcc9e2d51u;                                      \
    574   uint32_t _mur_c2 = 0x1b873593u;                                      \
    575   uint32_t _mur_k1 = 0;                                                \
    576   const uint8_t *_mur_tail;                                            \
    577   const uint32_t *_mur_blocks = (const uint32_t*)(_mur_data+(_mur_nblocks*4)); \
    578   int _mur_i;                                                          \
    579   for(_mur_i = -_mur_nblocks; _mur_i!=0; _mur_i++) {                   \
    580     _mur_k1 = MUR_GETBLOCK(_mur_blocks,_mur_i);                        \
    581     _mur_k1 *= _mur_c1;                                                \
    582     _mur_k1 = MUR_ROTL32(_mur_k1,15);                                  \
    583     _mur_k1 *= _mur_c2;                                                \
    584                                                                        \
    585     _mur_h1 ^= _mur_k1;                                                \
    586     _mur_h1 = MUR_ROTL32(_mur_h1,13);                                  \
    587     _mur_h1 = (_mur_h1*5U) + 0xe6546b64u;                              \
    588   }                                                                    \
    589   _mur_tail = (const uint8_t*)(_mur_data + (_mur_nblocks*4));          \
    590   _mur_k1=0;                                                           \
    591   switch((keylen) & 3U) {                                              \
    592     case 3: _mur_k1 ^= (uint32_t)_mur_tail[2] << 16; /* FALLTHROUGH */ \
    593     case 2: _mur_k1 ^= (uint32_t)_mur_tail[1] << 8;  /* FALLTHROUGH */ \
    594     case 1: _mur_k1 ^= (uint32_t)_mur_tail[0];                         \
    595     _mur_k1 *= _mur_c1;                                                \
    596     _mur_k1 = MUR_ROTL32(_mur_k1,15);                                  \
    597     _mur_k1 *= _mur_c2;                                                \
    598     _mur_h1 ^= _mur_k1;                                                \
    599   }                                                                    \
    600   _mur_h1 ^= (uint32_t)(keylen);                                       \
    601   MUR_FMIX(_mur_h1);                                                   \
    602   hashv = _mur_h1;                                                     \
    603   bkt = hashv & (num_bkts-1U);                                         \
    604 } while(0)
    605 #endif  /* HASH_USING_NO_STRICT_ALIASING */
    606 
    607 /* key comparison function; return 0 if keys equal */
    608 #define HASH_KEYCMP(a,b,len) memcmp(a,b,(unsigned long)(len))
    609 
    610 /* iterate over items in a known bucket to find desired item */
    611 #define HASH_FIND_IN_BKT(tbl,hh,head,keyptr,keylen_in,out)                       \
    612 do {                                                                             \
    613  if (head.hh_head != NULL) { DECLTYPE_ASSIGN(out,ELMT_FROM_HH(tbl,head.hh_head)); } \
    614  else { out=NULL; }                                                              \
    615  while (out != NULL) {                                                           \
    616     if ((out)->hh.keylen == (keylen_in)) {                                       \
    617         if ((HASH_KEYCMP((out)->hh.key,keyptr,keylen_in)) == 0) { break; }         \
    618     }                                                                            \
    619     if ((out)->hh.hh_next != NULL) { DECLTYPE_ASSIGN(out,ELMT_FROM_HH(tbl,(out)->hh.hh_next)); } \
    620     else { out = NULL; }                                                         \
    621  }                                                                               \
    622 } while(0)
    623 
    624 /* add an item to a bucket  */
    625 #define HASH_ADD_TO_BKT(head,addhh)                                              \
    626 do {                                                                             \
    627  head.count++;                                                                   \
    628  (addhh)->hh_next = head.hh_head;                                                \
    629  (addhh)->hh_prev = NULL;                                                        \
    630  if (head.hh_head != NULL) { (head).hh_head->hh_prev = (addhh); }                \
    631  (head).hh_head=addhh;                                                           \
    632  if ((head.count >= ((head.expand_mult+1U) * HASH_BKT_CAPACITY_THRESH))          \
    633      && ((addhh)->tbl->noexpand != 1U)) {                                        \
    634        HASH_EXPAND_BUCKETS((addhh)->tbl);                                        \
    635  }                                                                               \
    636 } while(0)
    637 
    638 /* remove an item from a given bucket */
    639 #define HASH_DEL_IN_BKT(hh,head,hh_del)                                          \
    640     (head).count--;                                                              \
    641     if ((head).hh_head == hh_del) {                                              \
    642       (head).hh_head = hh_del->hh_next;                                          \
    643     }                                                                            \
    644     if (hh_del->hh_prev) {                                                       \
    645         hh_del->hh_prev->hh_next = hh_del->hh_next;                              \
    646     }                                                                            \
    647     if (hh_del->hh_next) {                                                       \
    648         hh_del->hh_next->hh_prev = hh_del->hh_prev;                              \
    649     }
    650 
    651 /* Bucket expansion has the effect of doubling the number of buckets
    652  * and redistributing the items into the new buckets. Ideally the
    653  * items will distribute more or less evenly into the new buckets
    654  * (the extent to which this is true is a measure of the quality of
    655  * the hash function as it applies to the key domain).
    656  *
    657  * With the items distributed into more buckets, the chain length
    658  * (item count) in each bucket is reduced. Thus by expanding buckets
    659  * the hash keeps a bound on the chain length. This bounded chain
    660  * length is the essence of how a hash provides constant time lookup.
    661  *
    662  * The calculation of tbl->ideal_chain_maxlen below deserves some
    663  * explanation. First, keep in mind that we're calculating the ideal
    664  * maximum chain length based on the *new* (doubled) bucket count.
    665  * In fractions this is just n/b (n=number of items,b=new num buckets).
    666  * Since the ideal chain length is an integer, we want to calculate
    667  * ceil(n/b). We don't depend on floating point arithmetic in this
    668  * hash, so to calculate ceil(n/b) with integers we could write
    669  *
    670  *      ceil(n/b) = (n/b) + ((n%b)?1:0)
    671  *
    672  * and in fact a previous version of this hash did just that.
    673  * But now we have improved things a bit by recognizing that b is
    674  * always a power of two. We keep its base 2 log handy (call it lb),
    675  * so now we can write this with a bit shift and logical AND:
    676  *
    677  *      ceil(n/b) = (n>>lb) + ( (n & (b-1)) ? 1:0)
    678  *
    679  */
    680 #define HASH_EXPAND_BUCKETS(tbl)                                                 \
    681 do {                                                                             \
    682     unsigned _he_bkt;                                                            \
    683     unsigned _he_bkt_i;                                                          \
    684     struct UT_hash_handle *_he_thh, *_he_hh_nxt;                                 \
    685     UT_hash_bucket *_he_new_buckets, *_he_newbkt;                                \
    686     _he_new_buckets = (UT_hash_bucket*)uthash_malloc(                            \
    687              2UL * tbl->num_buckets * sizeof(struct UT_hash_bucket));            \
    688     if (!_he_new_buckets) { uthash_fatal( "out of memory"); }                    \
    689     memset(_he_new_buckets, 0,                                                   \
    690             2UL * tbl->num_buckets * sizeof(struct UT_hash_bucket));             \
    691     tbl->ideal_chain_maxlen =                                                    \
    692        (tbl->num_items >> (tbl->log2_num_buckets+1U)) +                          \
    693        (((tbl->num_items & ((tbl->num_buckets*2U)-1U)) != 0U) ? 1U : 0U);        \
    694     tbl->nonideal_items = 0;                                                     \
    695     for(_he_bkt_i = 0; _he_bkt_i < tbl->num_buckets; _he_bkt_i++)                \
    696     {                                                                            \
    697         _he_thh = tbl->buckets[ _he_bkt_i ].hh_head;                             \
    698         while (_he_thh != NULL) {                                                \
    699            _he_hh_nxt = _he_thh->hh_next;                                        \
    700            HASH_TO_BKT( _he_thh->hashv, tbl->num_buckets*2U, _he_bkt);           \
    701            _he_newbkt = &(_he_new_buckets[ _he_bkt ]);                           \
    702            if (++(_he_newbkt->count) > tbl->ideal_chain_maxlen) {                \
    703              tbl->nonideal_items++;                                              \
    704              _he_newbkt->expand_mult = _he_newbkt->count /                       \
    705                                         tbl->ideal_chain_maxlen;                 \
    706            }                                                                     \
    707            _he_thh->hh_prev = NULL;                                              \
    708            _he_thh->hh_next = _he_newbkt->hh_head;                               \
    709            if (_he_newbkt->hh_head != NULL) { _he_newbkt->hh_head->hh_prev =     \
    710                 _he_thh; }                                                       \
    711            _he_newbkt->hh_head = _he_thh;                                        \
    712            _he_thh = _he_hh_nxt;                                                 \
    713         }                                                                        \
    714     }                                                                            \
    715     uthash_free( tbl->buckets, tbl->num_buckets*sizeof(struct UT_hash_bucket) ); \
    716     tbl->num_buckets *= 2U;                                                      \
    717     tbl->log2_num_buckets++;                                                     \
    718     tbl->buckets = _he_new_buckets;                                              \
    719     tbl->ineff_expands = (tbl->nonideal_items > (tbl->num_items >> 1)) ?         \
    720         (tbl->ineff_expands+1U) : 0U;                                            \
    721     if (tbl->ineff_expands > 1U) {                                               \
    722         tbl->noexpand=1;                                                         \
    723         uthash_noexpand_fyi(tbl);                                                \
    724     }                                                                            \
    725     uthash_expand_fyi(tbl);                                                      \
    726 } while(0)
    727 
    728 
    729 /* This is an adaptation of Simon Tatham's O(n log(n)) mergesort */
    730 /* Note that HASH_SORT assumes the hash handle name to be hh.
    731  * HASH_SRT was added to allow the hash handle name to be passed in. */
    732 #define HASH_SORT(head,cmpfcn) HASH_SRT(hh,head,cmpfcn)
    733 #define HASH_SRT(hh,head,cmpfcn)                                                 \
    734 do {                                                                             \
    735   unsigned _hs_i;                                                                \
    736   unsigned _hs_looping,_hs_nmerges,_hs_insize,_hs_psize,_hs_qsize;               \
    737   struct UT_hash_handle *_hs_p, *_hs_q, *_hs_e, *_hs_list, *_hs_tail;            \
    738   if (head != NULL) {                                                            \
    739       _hs_insize = 1;                                                            \
    740       _hs_looping = 1;                                                           \
    741       _hs_list = &((head)->hh);                                                  \
    742       while (_hs_looping != 0U) {                                                \
    743           _hs_p = _hs_list;                                                      \
    744           _hs_list = NULL;                                                       \
    745           _hs_tail = NULL;                                                       \
    746           _hs_nmerges = 0;                                                       \
    747           while (_hs_p != NULL) {                                                \
    748               _hs_nmerges++;                                                     \
    749               _hs_q = _hs_p;                                                     \
    750               _hs_psize = 0;                                                     \
    751               for ( _hs_i = 0; _hs_i  < _hs_insize; _hs_i++ ) {                  \
    752                   _hs_psize++;                                                   \
    753                   _hs_q = (UT_hash_handle*)((_hs_q->next != NULL) ?              \
    754                           ((void*)((char*)(_hs_q->next) +                        \
    755                           (head)->hh.tbl->hho)) : NULL);                         \
    756                   if (! (_hs_q) ) { break; }                                     \
    757               }                                                                  \
    758               _hs_qsize = _hs_insize;                                            \
    759               while ((_hs_psize > 0U) || ((_hs_qsize > 0U) && (_hs_q != NULL))) {\
    760                   if (_hs_psize == 0U) {                                         \
    761                       _hs_e = _hs_q;                                             \
    762                       _hs_q = (UT_hash_handle*)((_hs_q->next != NULL) ?          \
    763                               ((void*)((char*)(_hs_q->next) +                    \
    764                               (head)->hh.tbl->hho)) : NULL);                     \
    765                       _hs_qsize--;                                               \
    766                   } else if ( (_hs_qsize == 0U) || (_hs_q == NULL) ) {           \
    767                       _hs_e = _hs_p;                                             \
    768                       if (_hs_p != NULL){                                        \
    769                         _hs_p = (UT_hash_handle*)((_hs_p->next != NULL) ?        \
    770                                 ((void*)((char*)(_hs_p->next) +                  \
    771                                 (head)->hh.tbl->hho)) : NULL);                   \
    772                        }                                                         \
    773                       _hs_psize--;                                               \
    774                   } else if ((                                                   \
    775                       cmpfcn(DECLTYPE(head)(ELMT_FROM_HH((head)->hh.tbl,_hs_p)), \
    776                              DECLTYPE(head)(ELMT_FROM_HH((head)->hh.tbl,_hs_q))) \
    777                              ) <= 0) {                                           \
    778                       _hs_e = _hs_p;                                             \
    779                       if (_hs_p != NULL){                                        \
    780                         _hs_p = (UT_hash_handle*)((_hs_p->next != NULL) ?        \
    781                                ((void*)((char*)(_hs_p->next) +                   \
    782                                (head)->hh.tbl->hho)) : NULL);                    \
    783                        }                                                         \
    784                       _hs_psize--;                                               \
    785                   } else {                                                       \
    786                       _hs_e = _hs_q;                                             \
    787                       _hs_q = (UT_hash_handle*)((_hs_q->next != NULL) ?          \
    788                               ((void*)((char*)(_hs_q->next) +                    \
    789                               (head)->hh.tbl->hho)) : NULL);                     \
    790                       _hs_qsize--;                                               \
    791                   }                                                              \
    792                   if ( _hs_tail != NULL ) {                                      \
    793                       _hs_tail->next = ((_hs_e != NULL) ?                        \
    794                             ELMT_FROM_HH((head)->hh.tbl,_hs_e) : NULL);          \
    795                   } else {                                                       \
    796                       _hs_list = _hs_e;                                          \
    797                   }                                                              \
    798                   if (_hs_e != NULL) {                                           \
    799                   _hs_e->prev = ((_hs_tail != NULL) ?                            \
    800                      ELMT_FROM_HH((head)->hh.tbl,_hs_tail) : NULL);              \
    801                   }                                                              \
    802                   _hs_tail = _hs_e;                                              \
    803               }                                                                  \
    804               _hs_p = _hs_q;                                                     \
    805           }                                                                      \
    806           if (_hs_tail != NULL){                                                 \
    807             _hs_tail->next = NULL;                                               \
    808           }                                                                      \
    809           if ( _hs_nmerges <= 1U ) {                                             \
    810               _hs_looping=0;                                                     \
    811               (head)->hh.tbl->tail = _hs_tail;                                   \
    812               DECLTYPE_ASSIGN(head,ELMT_FROM_HH((head)->hh.tbl, _hs_list));      \
    813           }                                                                      \
    814           _hs_insize *= 2U;                                                      \
    815       }                                                                          \
    816       HASH_FSCK(hh,head);                                                        \
    817  }                                                                               \
    818 } while (0)
    819 
    820 /* This function selects items from one hash into another hash.
    821  * The end result is that the selected items have dual presence
    822  * in both hashes. There is no copy of the items made; rather
    823  * they are added into the new hash through a secondary hash
    824  * hash handle that must be present in the structure. */
    825 #define HASH_SELECT(hh_dst, dst, hh_src, src, cond)                              \
    826 do {                                                                             \
    827   unsigned _src_bkt, _dst_bkt;                                                   \
    828   void *_last_elt=NULL, *_elt;                                                   \
    829   UT_hash_handle *_src_hh, *_dst_hh, *_last_elt_hh=NULL;                         \
    830   ptrdiff_t _dst_hho = ((char*)(&(dst)->hh_dst) - (char*)(dst));                 \
    831   if (src != NULL) {                                                             \
    832     for(_src_bkt=0; _src_bkt < (src)->hh_src.tbl->num_buckets; _src_bkt++) {     \
    833       for(_src_hh = (src)->hh_src.tbl->buckets[_src_bkt].hh_head;                \
    834           _src_hh != NULL;                                                       \
    835           _src_hh = _src_hh->hh_next) {                                          \
    836           _elt = ELMT_FROM_HH((src)->hh_src.tbl, _src_hh);                       \
    837           if (cond(_elt)) {                                                      \
    838             _dst_hh = (UT_hash_handle*)(((char*)_elt) + _dst_hho);               \
    839             _dst_hh->key = _src_hh->key;                                         \
    840             _dst_hh->keylen = _src_hh->keylen;                                   \
    841             _dst_hh->hashv = _src_hh->hashv;                                     \
    842             _dst_hh->prev = _last_elt;                                           \
    843             _dst_hh->next = NULL;                                                \
    844             if (_last_elt_hh != NULL) { _last_elt_hh->next = _elt; }             \
    845             if (dst == NULL) {                                                   \
    846               DECLTYPE_ASSIGN(dst,_elt);                                         \
    847               HASH_MAKE_TABLE(hh_dst,dst);                                       \
    848             } else {                                                             \
    849               _dst_hh->tbl = (dst)->hh_dst.tbl;                                  \
    850             }                                                                    \
    851             HASH_TO_BKT(_dst_hh->hashv, _dst_hh->tbl->num_buckets, _dst_bkt);    \
    852             HASH_ADD_TO_BKT(_dst_hh->tbl->buckets[_dst_bkt],_dst_hh);            \
    853             (dst)->hh_dst.tbl->num_items++;                                      \
    854             _last_elt = _elt;                                                    \
    855             _last_elt_hh = _dst_hh;                                              \
    856           }                                                                      \
    857       }                                                                          \
    858     }                                                                            \
    859   }                                                                              \
    860   HASH_FSCK(hh_dst,dst);                                                         \
    861 } while (0)
    862 
    863 #define HASH_CLEAR(hh,head)                                                      \
    864 do {                                                                             \
    865   if (head != NULL) {                                                            \
    866     uthash_free((head)->hh.tbl->buckets,                                         \
    867                 (head)->hh.tbl->num_buckets*sizeof(struct UT_hash_bucket));      \
    868     HASH_BLOOM_FREE((head)->hh.tbl);                                             \
    869     uthash_free((head)->hh.tbl, sizeof(UT_hash_table));                          \
    870     (head)=NULL;                                                                 \
    871   }                                                                              \
    872 } while(0)
    873 
    874 #define HASH_OVERHEAD(hh,head)                                                   \
    875  ((head != NULL) ? (                                                             \
    876  (size_t)(((head)->hh.tbl->num_items   * sizeof(UT_hash_handle))   +             \
    877           ((head)->hh.tbl->num_buckets * sizeof(UT_hash_bucket))   +             \
    878            sizeof(UT_hash_table)                                   +             \
    879            (HASH_BLOOM_BYTELEN))) : 0U)
    880 
    881 #ifdef NO_DECLTYPE
    882 #define HASH_ITER(hh,head,el,tmp)                                                \
    883 for(((el)=(head)), ((*(char**)(&(tmp)))=(char*)((head!=NULL)?(head)->hh.next:NULL)); \
    884   (el) != NULL; ((el)=(tmp)), ((*(char**)(&(tmp)))=(char*)((tmp!=NULL)?(tmp)->hh.next:NULL)))
    885 #else
    886 #define HASH_ITER(hh,head,el,tmp)                                                \
    887 for(((el)=(head)), ((tmp)=DECLTYPE(el)((head!=NULL)?(head)->hh.next:NULL));      \
    888   (el) != NULL; ((el)=(tmp)), ((tmp)=DECLTYPE(el)((tmp!=NULL)?(tmp)->hh.next:NULL)))
    889 #endif
    890 
    891 /* obtain a count of items in the hash */
    892 #define HASH_COUNT(head) HASH_CNT(hh,head)
    893 #define HASH_CNT(hh,head) ((head != NULL)?((head)->hh.tbl->num_items):0U)
    894 
    895 typedef struct UT_hash_bucket {
    896    struct UT_hash_handle *hh_head;
    897    unsigned count;
    898 
    899    /* expand_mult is normally set to 0. In this situation, the max chain length
    900     * threshold is enforced at its default value, HASH_BKT_CAPACITY_THRESH. (If
    901     * the bucket's chain exceeds this length, bucket expansion is triggered).
    902     * However, setting expand_mult to a non-zero value delays bucket expansion
    903     * (that would be triggered by additions to this particular bucket)
    904     * until its chain length reaches a *multiple* of HASH_BKT_CAPACITY_THRESH.
    905     * (The multiplier is simply expand_mult+1). The whole idea of this
    906     * multiplier is to reduce bucket expansions, since they are expensive, in
    907     * situations where we know that a particular bucket tends to be overused.
    908     * It is better to let its chain length grow to a longer yet-still-bounded
    909     * value, than to do an O(n) bucket expansion too often.
    910     */
    911    unsigned expand_mult;
    912 
    913 } UT_hash_bucket;
    914 
    915 /* random signature used only to find hash tables in external analysis */
    916 #define HASH_SIGNATURE 0xa0111fe1u
    917 #define HASH_BLOOM_SIGNATURE 0xb12220f2u
    918 
    919 typedef struct UT_hash_table {
    920    UT_hash_bucket *buckets;
    921    unsigned num_buckets, log2_num_buckets;
    922    unsigned num_items;
    923    struct UT_hash_handle *tail; /* tail hh in app order, for fast append    */
    924    ptrdiff_t hho; /* hash handle offset (byte pos of hash handle in element */
    925 
    926    /* in an ideal situation (all buckets used equally), no bucket would have
    927     * more than ceil(#items/#buckets) items. that's the ideal chain length. */
    928    unsigned ideal_chain_maxlen;
    929 
    930    /* nonideal_items is the number of items in the hash whose chain position
    931     * exceeds the ideal chain maxlen. these items pay the penalty for an uneven
    932     * hash distribution; reaching them in a chain traversal takes >ideal steps */
    933    unsigned nonideal_items;
    934 
    935    /* ineffective expands occur when a bucket doubling was performed, but
    936     * afterward, more than half the items in the hash had nonideal chain
    937     * positions. If this happens on two consecutive expansions we inhibit any
    938     * further expansion, as it's not helping; this happens when the hash
    939     * function isn't a good fit for the key domain. When expansion is inhibited
    940     * the hash will still work, albeit no longer in constant time. */
    941    unsigned ineff_expands, noexpand;
    942 
    943    uint32_t signature; /* used only to find hash tables in external analysis */
    944 #ifdef HASH_BLOOM
    945    uint32_t bloom_sig; /* used only to test bloom exists in external analysis */
    946    uint8_t *bloom_bv;
    947    uint8_t bloom_nbits;
    948 #endif
    949 
    950 } UT_hash_table;
    951 
    952 typedef struct UT_hash_handle {
    953    struct UT_hash_table *tbl;
    954    void *prev;                       /* prev element in app order      */
    955    void *next;                       /* next element in app order      */
    956    struct UT_hash_handle *hh_prev;   /* previous hh in bucket order    */
    957    struct UT_hash_handle *hh_next;   /* next hh in bucket order        */
    958    void *key;                        /* ptr to enclosing struct's key  */
    959    unsigned keylen;                  /* enclosing struct's key len     */
    960    unsigned hashv;                   /* result of hash-fcn(key)        */
    961 } UT_hash_handle;
    962 
    963 #endif /* UTHASH_H */