hash.h

   1 /* hash.h -- decls for hash table
   2 Copyright (C) 1995, 1999, 2002, 2010 Free Software Foundation, Inc.
   3 Written by Greg McGary <gkm@gnu.org> <greg@mcgary.org>
   4
   5 GNU Make is free software; you can redistribute it and/or modify it under the
   6 terms of the GNU General Public License as published by the Free Software
   7 Foundation; either version 3 of the License, or (at your option) any later
   8 version.
   9
  10 GNU Make is distributed in the hope that it will be useful, but WITHOUT ANY
  11 WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
  12 A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
  13
  14 You should have received a copy of the GNU General Public License along with
  15 this program.  If not, see <http://www.gnu.org/licenses/>.  */
  16
  17 #ifndef _hash_h_
  18 #define _hash_h_
  19
  20 #include <stdio.h>
  21 #include <ctype.h>
  22
  23 #if defined __cplusplus || (defined __STDC__ && __STDC__) || defined WINDOWS32
  24 # if !defined __GLIBC__ || !defined __P
  25 #  undef        __P
  26 #  define __P(protos)   protos
  27 # endif
  28 #else /* Not C++ or ANSI C.  */
  29 # undef __P
  30 # define __P(protos)    ()
  31 /* We can get away without defining `const' here only because in this file
  32    it is used only inside the prototype for `fnmatch', which is elided in
  33    non-ANSI C where `const' is problematical.  */
  34 #endif /* C++ or ANSI C.  */
  35
  36 typedef unsigned long (*hash_func_t) __P((void const *key));
  37 typedef int (*hash_cmp_func_t) __P((void const *x, void const *y));
  38 typedef void (*hash_map_func_t) __P((void const *item));
  39 typedef void (*hash_map_arg_func_t) __P((void const *item, void *arg));
  40
  41 struct hash_table
  42 {
  43   void **ht_vec;
  44   unsigned long ht_size;        /* total number of slots (power of 2) */
  45   unsigned long ht_capacity;    /* usable slots, limited by loading-factor */
  46   unsigned long ht_fill;        /* items in table */
  47   unsigned long ht_empty_slots; /* empty slots not including deleted slots */
  48   unsigned long ht_collisions;  /* # of failed calls to comparison function */
  49   unsigned long ht_lookups;     /* # of queries */
  50   unsigned int ht_rehashes;     /* # of times we've expanded table */
  51   hash_func_t ht_hash_1;        /* primary hash function */
  52   hash_func_t ht_hash_2;        /* secondary hash function */
  53   hash_cmp_func_t ht_compare;   /* comparison function */
  54 };
  55
  56 typedef int (*qsort_cmp_t) __P((void const *, void const *));
  57
  58 void hash_init __P((struct hash_table *ht, unsigned long size,
  59                     hash_func_t hash_1, hash_func_t hash_2, hash_cmp_func_t hash_cmp));
  60 void hash_load __P((struct hash_table *ht, void *item_table,
  61                     unsigned long cardinality, unsigned long size));
  62 void **hash_find_slot __P((struct hash_table *ht, void const *key));
  63 void *hash_find_item __P((struct hash_table *ht, void const *key));
  64 void *hash_insert __P((struct hash_table *ht, const void *item));
  65 void *hash_insert_at __P((struct hash_table *ht, const void *item, void const *slot));
  66 void *hash_delete __P((struct hash_table *ht, void const *item));
  67 void *hash_delete_at __P((struct hash_table *ht, void const *slot));
  68 void hash_delete_items __P((struct hash_table *ht));
  69 void hash_free_items __P((struct hash_table *ht));
  70 void hash_free __P((struct hash_table *ht, int free_items));
  71 void hash_map __P((struct hash_table *ht, hash_map_func_t map));
  72 void hash_map_arg __P((struct hash_table *ht, hash_map_arg_func_t map, void *arg));
  73 void hash_print_stats __P((struct hash_table *ht, FILE *out_FILE));
  74 void **hash_dump __P((struct hash_table *ht, void **vector_0, qsort_cmp_t compare));
  75
  76 extern void *hash_deleted_item;
  77 #define HASH_VACANT(item) ((item) == 0 || (void *) (item) == hash_deleted_item)
  78
  79 \f
  80 /* hash and comparison macros for case-sensitive string keys. */
  81
  82 /* Due to the strcache, it's not uncommon for the string pointers to
  83    be identical.  Take advantage of that to short-circuit string compares.  */
  84
  85 #define STRING_HASH_1(KEY, RESULT) do { \
  86   unsigned char const *_key_ = (unsigned char const *) (KEY) - 1; \
  87   while (*++_key_) \
  88     (RESULT) += (*_key_ << (_key_[1] & 0xf)); \
  89 } while (0)
  90 #define return_STRING_HASH_1(KEY) do { \
  91   unsigned long _result_ = 0; \
  92   STRING_HASH_1 ((KEY), _result_); \
  93   return _result_; \
  94 } while (0)
  95
  96 #define STRING_HASH_2(KEY, RESULT) do { \
  97   unsigned char const *_key_ = (unsigned char const *) (KEY) - 1; \
  98   while (*++_key_) \
  99     (RESULT) += (*_key_ << (_key_[1] & 0x7)); \
 100 } while (0)
 101 #define return_STRING_HASH_2(KEY) do { \
 102   unsigned long _result_ = 0; \
 103   STRING_HASH_2 ((KEY), _result_); \
 104   return _result_; \
 105 } while (0)
 106
 107 #define STRING_COMPARE(X, Y, RESULT) do { \
 108     RESULT = (X) == (Y) ? 0 : strcmp ((X), (Y)); \
 109 } while (0)
 110 #define return_STRING_COMPARE(X, Y) do { \
 111   return (X) == (Y) ? 0 : strcmp ((X), (Y)); \
 112 } while (0)
 113
 114
 115 #define STRING_N_HASH_1(KEY, N, RESULT) do { \
 116   unsigned char const *_key_ = (unsigned char const *) (KEY) - 1; \
 117   int _n_ = (N); \
 118   if (_n_) \
 119     while (--_n_ && *++_key_) \
 120       (RESULT) += (*_key_ << (_key_[1] & 0xf)); \
 121   (RESULT) += *++_key_; \
 122 } while (0)
 123 #define return_STRING_N_HASH_1(KEY, N) do { \
 124   unsigned long _result_ = 0; \
 125   STRING_N_HASH_1 ((KEY), (N), _result_); \
 126   return _result_; \
 127 } while (0)
 128
 129 #define STRING_N_HASH_2(KEY, N, RESULT) do { \
 130   unsigned char const *_key_ = (unsigned char const *) (KEY) - 1; \
 131   int _n_ = (N); \
 132   if (_n_) \
 133     while (--_n_ && *++_key_) \
 134       (RESULT) += (*_key_ << (_key_[1] & 0x7)); \
 135   (RESULT) += *++_key_; \
 136 } while (0)
 137 #define return_STRING_N_HASH_2(KEY, N) do { \
 138   unsigned long _result_ = 0; \
 139   STRING_N_HASH_2 ((KEY), (N), _result_); \
 140   return _result_; \
 141 } while (0)
 142
 143 #define STRING_N_COMPARE(X, Y, N, RESULT) do { \
 144   RESULT = (X) == (Y) ? 0 : strncmp ((X), (Y), (N)); \
 145 } while (0)
 146 #define return_STRING_N_COMPARE(X, Y, N) do { \
 147   return (X) == (Y) ? 0 : strncmp ((X), (Y), (N)); \
 148 } while (0)
 149
 150 #ifdef HAVE_CASE_INSENSITIVE_FS
 151
 152 /* hash and comparison macros for case-insensitive string _key_s. */
 153
 154 #define ISTRING_HASH_1(KEY, RESULT) do { \
 155   unsigned char const *_key_ = (unsigned char const *) (KEY) - 1; \
 156   while (*++_key_) \
 157     (RESULT) += ((isupper (*_key_) ? tolower (*_key_) : *_key_) << (_key_[1] & 0xf)); \
 158 } while (0)
 159 #define return_ISTRING_HASH_1(KEY) do { \
 160   unsigned long _result_ = 0; \
 161   ISTRING_HASH_1 ((KEY), _result_); \
 162   return _result_; \
 163 } while (0)
 164
 165 #define ISTRING_HASH_2(KEY, RESULT) do { \
 166   unsigned char const *_key_ = (unsigned char const *) (KEY) - 1; \
 167   while (*++_key_) \
 168     (RESULT) += ((isupper (*_key_) ? tolower (*_key_) : *_key_) << (_key_[1] & 0x7)); \
 169 } while (0)
 170 #define return_ISTRING_HASH_2(KEY) do { \
 171   unsigned long _result_ = 0; \
 172   ISTRING_HASH_2 ((KEY), _result_); \
 173   return _result_; \
 174 } while (0)
 175
 176 #define ISTRING_COMPARE(X, Y, RESULT) do { \
 177   RESULT = (X) == (Y) ? 0 : strcasecmp ((X), (Y)); \
 178 } while (0)
 179 #define return_ISTRING_COMPARE(X, Y) do { \
 180   return (X) == (Y) ? 0 : strcasecmp ((X), (Y)); \
 181 } while (0)
 182
 183 #else
 184
 185 #define ISTRING_HASH_1(KEY, RESULT) STRING_HASH_1 ((KEY), (RESULT))
 186 #define return_ISTRING_HASH_1(KEY) return_STRING_HASH_1 (KEY)
 187
 188 #define ISTRING_HASH_2(KEY, RESULT) STRING_HASH_2 ((KEY), (RESULT))
 189 #define return_ISTRING_HASH_2(KEY) return_STRING_HASH_2 (KEY)
 190
 191 #define ISTRING_COMPARE(X, Y, RESULT) STRING_COMPARE ((X), (Y), (RESULT))
 192 #define return_ISTRING_COMPARE(X, Y) return_STRING_COMPARE ((X), (Y))
 193
 194 #endif
 195
 196 /* hash and comparison macros for integer _key_s. */
 197
 198 #define INTEGER_HASH_1(KEY, RESULT) do { \
 199   (RESULT) += ((unsigned long)(KEY)); \
 200 } while (0)
 201 #define return_INTEGER_HASH_1(KEY) do { \
 202   unsigned long _result_ = 0; \
 203   INTEGER_HASH_1 ((KEY), _result_); \
 204   return _result_; \
 205 } while (0)
 206
 207 #define INTEGER_HASH_2(KEY, RESULT) do { \
 208   (RESULT) += ~((unsigned long)(KEY)); \
 209 } while (0)
 210 #define return_INTEGER_HASH_2(KEY) do { \
 211   unsigned long _result_ = 0; \
 212   INTEGER_HASH_2 ((KEY), _result_); \
 213   return _result_; \
 214 } while (0)
 215
 216 #define INTEGER_COMPARE(X, Y, RESULT) do { \
 217   (RESULT) = X - Y; \
 218 } while (0)
 219 #define return_INTEGER_COMPARE(X, Y) do { \
 220   int _result_; \
 221   INTEGER_COMPARE (X, Y, _result_); \
 222   return _result_; \
 223 } while (0)
 224
 225 /* hash and comparison macros for address keys. */
 226
 227 #define ADDRESS_HASH_1(KEY, RESULT) INTEGER_HASH_1 (((unsigned long)(KEY)) >> 3, (RESULT))
 228 #define ADDRESS_HASH_2(KEY, RESULT) INTEGER_HASH_2 (((unsigned long)(KEY)) >> 3, (RESULT))
 229 #define ADDRESS_COMPARE(X, Y, RESULT) INTEGER_COMPARE ((X), (Y), (RESULT))
 230 #define return_ADDRESS_HASH_1(KEY) return_INTEGER_HASH_1 (((unsigned long)(KEY)) >> 3)
 231 #define return_ADDRESS_HASH_2(KEY) return_INTEGER_HASH_2 (((unsigned long)(KEY)) >> 3)
 232 #define return_ADDRESS_COMPARE(X, Y) return_INTEGER_COMPARE ((X), (Y))
 233
 234 #endif /* not _hash_h_ */