1 /* Copyright (C) 1995, 2000-2003, 2005-2006 Free Software Foundation, Inc. 2 3 The GNU C Library is free software; you can redistribute it and/or 4 modify it under the terms of the GNU Library General Public License as 5 published by the Free Software Foundation; either version 2 of the 6 License, or (at your option) any later version. 7 8 The GNU C Library is distributed in the hope that it will be useful, 9 but WITHOUT ANY WARRANTY; without even the implied warranty of 10 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 11 Library General Public License for more details. 12 13 You should have received a copy of the GNU Library General Public 14 License along with the GNU C Library; see the file COPYING.LIB. If 15 not, write to the Free Software Foundation, Inc., 51 Franklin Street, 16 Fifth Floor, Boston, MA 02110-1301, USA. */ 17 18 #ifndef _HASH_H 19 #define _HASH_H 20 21 #include "obstack.h" 22 23 #ifdef __cplusplus 24 extern "C" { 25 #endif 26 27 struct hash_entry; 28 29 typedef struct hash_table 30 { 31 unsigned long int size; /* Number of allocated entries. */ 32 unsigned long int filled; /* Number of used entries. */ 33 struct hash_entry *first; /* Pointer to head of list of entries. */ 34 struct hash_entry *table; /* Pointer to array of entries. */ 35 struct obstack mem_pool; /* Memory pool holding the keys. */ 36 } 37 hash_table; 38 39 /* Initialize a hash table. INIT_SIZE > 1 is the initial number of available 40 entries. 41 Return 0 upon successful completion, -1 upon memory allocation error. */ 42 extern int hash_init (hash_table *htab, unsigned long int init_size); 43 44 /* Delete a hash table's contents. 45 Return 0 always. */ 46 extern int hash_destroy (hash_table *htab); 47 48 /* Look up the value of a key in the given table. 49 If found, return 0 and set *RESULT to it. Otherwise return -1. */ 50 extern int hash_find_entry (hash_table *htab, 51 const void *key, size_t keylen, 52 void **result); 53 54 /* Try to insert the pair (KEY[0..KEYLEN-1], DATA) in the hash table. 55 Return non-NULL (more precisely, the address of the KEY inside the table's 56 memory pool) if successful, or NULL if there is already an entry with the 57 given key. */ 58 extern const void * hash_insert_entry (hash_table *htab, 59 const void *key, size_t keylen, 60 void *data); 61 62 /* Insert the pair (KEY[0..KEYLEN-1], DATA) in the hash table. 63 Return 0. */ 64 extern int hash_set_value (hash_table *htab, 65 const void *key, size_t keylen, 66 void *data); 67 68 /* Steps *PTR forward to the next used entry in the given hash table. *PTR 69 should be initially set to NULL. Store information about the next entry 70 in *KEY, *KEYLEN, *DATA. 71 Return 0 normally, -1 when the whole hash table has been traversed. */ 72 extern int hash_iterate (hash_table *htab, void **ptr, 73 const void **key, size_t *keylen, 74 void **data); 75 76 /* Steps *PTR forward to the next used entry in the given hash table. *PTR 77 should be initially set to NULL. Store information about the next entry 78 in *KEY, *KEYLEN, *DATAP. *DATAP is set to point to the storage of the 79 value; modifying **DATAP will modify the value of the entry. 80 Return 0 normally, -1 when the whole hash table has been traversed. */ 81 extern int hash_iterate_modify (hash_table *htab, void **ptr, 82 const void **key, size_t *keylen, 83 void ***datap); 84 85 /* Given SEED > 1, return the smallest odd prime number >= SEED. */ 86 extern unsigned long int next_prime (unsigned long int seed); 87 88 #ifdef __cplusplus 89 } 90 #endif 91 92 #endif /* not _HASH_H */ 93