khash.hon commit general improvements (43abf13)
   1/* The MIT License
   2
   3   Copyright (c) 2008, 2009, 2011 by Attractive Chaos <attractor@live.co.uk>
   4
   5   Permission is hereby granted, free of charge, to any person obtaining
   6   a copy of this software and associated documentation files (the
   7   "Software"), to deal in the Software without restriction, including
   8   without limitation the rights to use, copy, modify, merge, publish,
   9   distribute, sublicense, and/or sell copies of the Software, and to
  10   permit persons to whom the Software is furnished to do so, subject to
  11   the following conditions:
  12
  13   The above copyright notice and this permission notice shall be
  14   included in all copies or substantial portions of the Software.
  15
  16   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  17   EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  18   MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  19   NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  20   BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  21   ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  22   CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  23   SOFTWARE.
  24*/
  25
  26#ifndef __AC_KHASH_H
  27#define __AC_KHASH_H
  28
  29#include "cache.h"
  30#include "hashmap.h"
  31
  32#define AC_VERSION_KHASH_H "0.2.8"
  33
  34typedef uint32_t khint32_t;
  35typedef uint64_t khint64_t;
  36
  37typedef khint32_t khint_t;
  38typedef khint_t khiter_t;
  39
  40#define __ac_isempty(flag, i) ((flag[i>>4]>>((i&0xfU)<<1))&2)
  41#define __ac_isdel(flag, i) ((flag[i>>4]>>((i&0xfU)<<1))&1)
  42#define __ac_iseither(flag, i) ((flag[i>>4]>>((i&0xfU)<<1))&3)
  43#define __ac_set_isdel_false(flag, i) (flag[i>>4]&=~(1ul<<((i&0xfU)<<1)))
  44#define __ac_set_isempty_false(flag, i) (flag[i>>4]&=~(2ul<<((i&0xfU)<<1)))
  45#define __ac_set_isboth_false(flag, i) (flag[i>>4]&=~(3ul<<((i&0xfU)<<1)))
  46#define __ac_set_isdel_true(flag, i) (flag[i>>4]|=1ul<<((i&0xfU)<<1))
  47
  48#define __ac_fsize(m) ((m) < 16? 1 : (m)>>4)
  49
  50#define kroundup32(x) (--(x), (x)|=(x)>>1, (x)|=(x)>>2, (x)|=(x)>>4, (x)|=(x)>>8, (x)|=(x)>>16, ++(x))
  51
  52static inline khint_t __ac_X31_hash_string(const char *s)
  53{
  54        khint_t h = (khint_t)*s;
  55        if (h) for (++s ; *s; ++s) h = (h << 5) - h + (khint_t)*s;
  56        return h;
  57}
  58
  59#define kh_str_hash_func(key) __ac_X31_hash_string(key)
  60#define kh_str_hash_equal(a, b) (strcmp(a, b) == 0)
  61
  62static const double __ac_HASH_UPPER = 0.77;
  63
  64#define __KHASH_TYPE(name, khkey_t, khval_t) \
  65        typedef struct { \
  66                khint_t n_buckets, size, n_occupied, upper_bound; \
  67                khint32_t *flags; \
  68                khkey_t *keys; \
  69                khval_t *vals; \
  70        } kh_##name##_t;
  71
  72#define __KHASH_PROTOTYPES(name, khkey_t, khval_t)                              \
  73        kh_##name##_t *kh_init_##name(void);                                            \
  74        void kh_destroy_##name(kh_##name##_t *h);                                       \
  75        void kh_clear_##name(kh_##name##_t *h);                                         \
  76        khint_t kh_get_##name(const kh_##name##_t *h, khkey_t key); \
  77        int kh_resize_##name(kh_##name##_t *h, khint_t new_n_buckets); \
  78        khint_t kh_put_##name(kh_##name##_t *h, khkey_t key, int *ret); \
  79        void kh_del_##name(kh_##name##_t *h, khint_t x);
  80
  81#define __KHASH_IMPL(name, SCOPE, khkey_t, khval_t, kh_is_map, __hash_func, __hash_equal) \
  82        SCOPE kh_##name##_t *kh_init_##name(void) {                                                     \
  83                return (kh_##name##_t*)xcalloc(1, sizeof(kh_##name##_t));               \
  84        }                                                                                                                                       \
  85        SCOPE void kh_release_##name(kh_##name##_t *h)                                          \
  86        {                                                                                                                                       \
  87                free(h->flags);                                                                                                 \
  88                free((void *)h->keys);                                                                                  \
  89                free((void *)h->vals);                                                                                  \
  90        }                                                                                                                                       \
  91        SCOPE void kh_destroy_##name(kh_##name##_t *h)                                          \
  92        {                                                                                                                                       \
  93                if (h) {                                                                                                                \
  94                        kh_release_##name(h);                                                                           \
  95                        free(h);                                                                                                        \
  96                }                                                                                                                               \
  97        }                                                                                                                                       \
  98        SCOPE void kh_clear_##name(kh_##name##_t *h)                                            \
  99        {                                                                                                                                       \
 100                if (h && h->flags) {                                                                                    \
 101                        memset(h->flags, 0xaa, __ac_fsize(h->n_buckets) * sizeof(khint32_t)); \
 102                        h->size = h->n_occupied = 0;                                                            \
 103                }                                                                                                                               \
 104        }                                                                                                                                       \
 105        SCOPE khint_t kh_get_##name(const kh_##name##_t *h, khkey_t key)        \
 106        {                                                                                                                                       \
 107                if (h->n_buckets) {                                                                                             \
 108                        khint_t k, i, last, mask, step = 0; \
 109                        mask = h->n_buckets - 1;                                                                        \
 110                        k = __hash_func(key); i = k & mask;                                                     \
 111                        last = i; \
 112                        while (!__ac_isempty(h->flags, i) && (__ac_isdel(h->flags, i) || !__hash_equal(h->keys[i], key))) { \
 113                                i = (i + (++step)) & mask; \
 114                                if (i == last) return h->n_buckets;                                             \
 115                        }                                                                                                                       \
 116                        return __ac_iseither(h->flags, i)? h->n_buckets : i;            \
 117                } else return 0;                                                                                                \
 118        }                                                                                                                                       \
 119        SCOPE int kh_resize_##name(kh_##name##_t *h, khint_t new_n_buckets) \
 120        { /* This function uses 0.25*n_buckets bytes of working space instead of [sizeof(key_t+val_t)+.25]*n_buckets. */ \
 121                khint32_t *new_flags = NULL;                                                                            \
 122                khint_t j = 1;                                                                                                  \
 123                {                                                                                                                               \
 124                        kroundup32(new_n_buckets);                                                                      \
 125                        if (new_n_buckets < 4) new_n_buckets = 4;                                       \
 126                        if (h->size >= (khint_t)(new_n_buckets * __ac_HASH_UPPER + 0.5)) j = 0; /* requested size is too small */ \
 127                        else { /* hash table size to be changed (shrink or expand); rehash */ \
 128                                ALLOC_ARRAY(new_flags, __ac_fsize(new_n_buckets)); \
 129                                if (!new_flags) return -1;                                                              \
 130                                memset(new_flags, 0xaa, __ac_fsize(new_n_buckets) * sizeof(khint32_t)); \
 131                                if (h->n_buckets < new_n_buckets) {     /* expand */            \
 132                                        REALLOC_ARRAY(h->keys, new_n_buckets); \
 133                                        if (kh_is_map) {                                                                        \
 134                                                REALLOC_ARRAY(h->vals, new_n_buckets); \
 135                                        }                                                                                                       \
 136                                } /* otherwise shrink */                                                                \
 137                        }                                                                                                                       \
 138                }                                                                                                                               \
 139                if (j) { /* rehashing is needed */                                                              \
 140                        for (j = 0; j != h->n_buckets; ++j) {                                           \
 141                                if (__ac_iseither(h->flags, j) == 0) {                                  \
 142                                        khkey_t key = h->keys[j];                                                       \
 143                                        khval_t val;                                                                            \
 144                                        khint_t new_mask;                                                                       \
 145                                        new_mask = new_n_buckets - 1;                                           \
 146                                        if (kh_is_map) val = h->vals[j];                                        \
 147                                        __ac_set_isdel_true(h->flags, j);                                       \
 148                                        while (1) { /* kick-out process; sort of like in Cuckoo hashing */ \
 149                                                khint_t k, i, step = 0; \
 150                                                k = __hash_func(key);                                                   \
 151                                                i = k & new_mask;                                                               \
 152                                                while (!__ac_isempty(new_flags, i)) i = (i + (++step)) & new_mask; \
 153                                                __ac_set_isempty_false(new_flags, i);                   \
 154                                                if (i < h->n_buckets && __ac_iseither(h->flags, i) == 0) { /* kick out the existing element */ \
 155                                                        { khkey_t tmp = h->keys[i]; h->keys[i] = key; key = tmp; } \
 156                                                        if (kh_is_map) { khval_t tmp = h->vals[i]; h->vals[i] = val; val = tmp; } \
 157                                                        __ac_set_isdel_true(h->flags, i); /* mark it as deleted in the old hash table */ \
 158                                                } else { /* write the element and jump out of the loop */ \
 159                                                        h->keys[i] = key;                                                       \
 160                                                        if (kh_is_map) h->vals[i] = val;                        \
 161                                                        break;                                                                          \
 162                                                }                                                                                               \
 163                                        }                                                                                                       \
 164                                }                                                                                                               \
 165                        }                                                                                                                       \
 166                        if (h->n_buckets > new_n_buckets) { /* shrink the hash table */ \
 167                                REALLOC_ARRAY(h->keys, new_n_buckets); \
 168                                if (kh_is_map) REALLOC_ARRAY(h->vals, new_n_buckets); \
 169                        }                                                                                                                       \
 170                        free(h->flags); /* free the working space */                            \
 171                        h->flags = new_flags;                                                                           \
 172                        h->n_buckets = new_n_buckets;                                                           \
 173                        h->n_occupied = h->size;                                                                        \
 174                        h->upper_bound = (khint_t)(h->n_buckets * __ac_HASH_UPPER + 0.5); \
 175                }                                                                                                                               \
 176                return 0;                                                                                                               \
 177        }                                                                                                                                       \
 178        SCOPE khint_t kh_put_##name(kh_##name##_t *h, khkey_t key, int *ret) \
 179        {                                                                                                                                       \
 180                khint_t x;                                                                                                              \
 181                if (h->n_occupied >= h->upper_bound) { /* update the hash table */ \
 182                        if (h->n_buckets > (h->size<<1)) {                                                      \
 183                                if (kh_resize_##name(h, h->n_buckets - 1) < 0) { /* clear "deleted" elements */ \
 184                                        *ret = -1; return h->n_buckets;                                         \
 185                                }                                                                                                               \
 186                        } else if (kh_resize_##name(h, h->n_buckets + 1) < 0) { /* expand the hash table */ \
 187                                *ret = -1; return h->n_buckets;                                                 \
 188                        }                                                                                                                       \
 189                } /* TODO: to implement automatically shrinking; resize() already support shrinking */ \
 190                {                                                                                                                               \
 191                        khint_t k, i, site, last, mask = h->n_buckets - 1, step = 0; \
 192                        x = site = h->n_buckets; k = __hash_func(key); i = k & mask; \
 193                        if (__ac_isempty(h->flags, i)) x = i; /* for speed up */        \
 194                        else {                                                                                                          \
 195                                last = i; \
 196                                while (!__ac_isempty(h->flags, i) && (__ac_isdel(h->flags, i) || !__hash_equal(h->keys[i], key))) { \
 197                                        if (__ac_isdel(h->flags, i)) site = i;                          \
 198                                        i = (i + (++step)) & mask; \
 199                                        if (i == last) { x = site; break; }                                     \
 200                                }                                                                                                               \
 201                                if (x == h->n_buckets) {                                                                \
 202                                        if (__ac_isempty(h->flags, i) && site != h->n_buckets) x = site; \
 203                                        else x = i;                                                                                     \
 204                                }                                                                                                               \
 205                        }                                                                                                                       \
 206                }                                                                                                                               \
 207                if (__ac_isempty(h->flags, x)) { /* not present at all */               \
 208                        h->keys[x] = key;                                                                                       \
 209                        __ac_set_isboth_false(h->flags, x);                                                     \
 210                        ++h->size; ++h->n_occupied;                                                                     \
 211                        *ret = 1;                                                                                                       \
 212                } else if (__ac_isdel(h->flags, x)) { /* deleted */                             \
 213                        h->keys[x] = key;                                                                                       \
 214                        __ac_set_isboth_false(h->flags, x);                                                     \
 215                        ++h->size;                                                                                                      \
 216                        *ret = 2;                                                                                                       \
 217                } else *ret = 0; /* Don't touch h->keys[x] if present and not deleted */ \
 218                return x;                                                                                                               \
 219        }                                                                                                                                       \
 220        SCOPE void kh_del_##name(kh_##name##_t *h, khint_t x)                           \
 221        {                                                                                                                                       \
 222                if (x != h->n_buckets && !__ac_iseither(h->flags, x)) {                 \
 223                        __ac_set_isdel_true(h->flags, x);                                                       \
 224                        --h->size;                                                                                                      \
 225                }                                                                                                                               \
 226        }
 227
 228#define KHASH_DECLARE(name, khkey_t, khval_t)                                                   \
 229        __KHASH_TYPE(name, khkey_t, khval_t)                                                            \
 230        __KHASH_PROTOTYPES(name, khkey_t, khval_t)
 231
 232#define KHASH_INIT2(name, SCOPE, khkey_t, khval_t, kh_is_map, __hash_func, __hash_equal) \
 233        __KHASH_TYPE(name, khkey_t, khval_t)                                                            \
 234        __KHASH_IMPL(name, SCOPE, khkey_t, khval_t, kh_is_map, __hash_func, __hash_equal)
 235
 236#define KHASH_INIT(name, khkey_t, khval_t, kh_is_map, __hash_func, __hash_equal) \
 237        KHASH_INIT2(name, MAYBE_UNUSED static inline, khkey_t, khval_t, kh_is_map, __hash_func, __hash_equal)
 238
 239/* Other convenient macros... */
 240
 241/*! @function
 242  @abstract     Test whether a bucket contains data.
 243  @param  h     Pointer to the hash table [khash_t(name)*]
 244  @param  x     Iterator to the bucket [khint_t]
 245  @return       1 if containing data; 0 otherwise [int]
 246 */
 247#define kh_exist(h, x) (!__ac_iseither((h)->flags, (x)))
 248
 249/*! @function
 250  @abstract     Get key given an iterator
 251  @param  h     Pointer to the hash table [khash_t(name)*]
 252  @param  x     Iterator to the bucket [khint_t]
 253  @return       Key [type of keys]
 254 */
 255#define kh_key(h, x) ((h)->keys[x])
 256
 257/*! @function
 258  @abstract     Get value given an iterator
 259  @param  h     Pointer to the hash table [khash_t(name)*]
 260  @param  x     Iterator to the bucket [khint_t]
 261  @return       Value [type of values]
 262  @discussion   For hash sets, calling this results in segfault.
 263 */
 264#define kh_val(h, x) ((h)->vals[x])
 265
 266/*! @function
 267  @abstract     Alias of kh_val()
 268 */
 269#define kh_value(h, x) ((h)->vals[x])
 270
 271/*! @function
 272  @abstract     Get the start iterator
 273  @param  h     Pointer to the hash table [khash_t(name)*]
 274  @return       The start iterator [khint_t]
 275 */
 276#define kh_begin(h) (khint_t)(0)
 277
 278/*! @function
 279  @abstract     Get the end iterator
 280  @param  h     Pointer to the hash table [khash_t(name)*]
 281  @return       The end iterator [khint_t]
 282 */
 283#define kh_end(h) ((h)->n_buckets)
 284
 285/*! @function
 286  @abstract     Get the number of elements in the hash table
 287  @param  h     Pointer to the hash table [khash_t(name)*]
 288  @return       Number of elements in the hash table [khint_t]
 289 */
 290#define kh_size(h) ((h)->size)
 291
 292/*! @function
 293  @abstract     Get the number of buckets in the hash table
 294  @param  h     Pointer to the hash table [khash_t(name)*]
 295  @return       Number of buckets in the hash table [khint_t]
 296 */
 297#define kh_n_buckets(h) ((h)->n_buckets)
 298
 299/*! @function
 300  @abstract     Iterate over the entries in the hash table
 301  @param  h     Pointer to the hash table [khash_t(name)*]
 302  @param  kvar  Variable to which key will be assigned
 303  @param  vvar  Variable to which value will be assigned
 304  @param  code  Block of code to execute
 305 */
 306#define kh_foreach(h, kvar, vvar, code) { khint_t __i;          \
 307        for (__i = kh_begin(h); __i != kh_end(h); ++__i) {              \
 308                if (!kh_exist(h,__i)) continue;                                         \
 309                (kvar) = kh_key(h,__i);                                                         \
 310                (vvar) = kh_val(h,__i);                                                         \
 311                code;                                                                                           \
 312        } }
 313
 314/*! @function
 315  @abstract     Iterate over the values in the hash table
 316  @param  h     Pointer to the hash table [khash_t(name)*]
 317  @param  vvar  Variable to which value will be assigned
 318  @param  code  Block of code to execute
 319 */
 320#define kh_foreach_value(h, vvar, code) { khint_t __i;          \
 321        for (__i = kh_begin(h); __i != kh_end(h); ++__i) {              \
 322                if (!kh_exist(h,__i)) continue;                                         \
 323                (vvar) = kh_val(h,__i);                                                         \
 324                code;                                                                                           \
 325        } }
 326
 327static inline unsigned int oidhash_by_value(struct object_id oid)
 328{
 329        return oidhash(&oid);
 330}
 331
 332static inline int oideq_by_value(struct object_id a, struct object_id b)
 333{
 334        return oideq(&a, &b);
 335}
 336
 337KHASH_INIT(oid_set, struct object_id, int, 0, oidhash_by_value, oideq_by_value)
 338
 339KHASH_INIT(oid_map, struct object_id, void *, 1, oidhash_by_value, oideq_by_value)
 340
 341KHASH_INIT(oid_pos, struct object_id, int, 1, oidhash_by_value, oideq_by_value)
 342
 343#endif /* __AC_KHASH_H */