-#ifndef HASH_H
-# define HASH_H 1
-
-# if HAVE_CONFIG_H
-# include <config.h>
-# endif
-
-# include <stdio.h>
-# include <assert.h>
-
-# ifdef STDC_HEADERS
-# include <stdlib.h>
-# endif
-
-# ifndef HAVE_DECL_FREE
-void free ();
+/* hash - hashing table processing.
+ Copyright (C) 1998 Free Software Foundation, Inc.
+ Written by Jim Meyering <meyering@ascend.com>, 1998.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software Foundation,
+ Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
+
+/* A generic hash table package. */
+
+/* Make sure USE_OBSTACK is defined to 1 if you want the allocator to use
+ obstacks instead of malloc, and recompile `hash.c' with same setting. */
+
+#ifndef PARAMS
+# if PROTOTYPES || __STDC__
+# define PARAMS(Args) Args
+# else
+# define PARAMS(Args) ()
# endif
+#endif
-# ifndef HAVE_DECL_MALLOC
-char *malloc ();
-# endif
+typedef unsigned int (*Hash_hasher) PARAMS ((const void *, unsigned int));
+typedef bool (*Hash_comparator) PARAMS ((const void *, const void *));
+typedef void (*Hash_data_freer) PARAMS ((void *));
+typedef bool (*Hash_processor) PARAMS ((void *, void *));
-# ifndef PARAMS
-# if defined PROTOTYPES || (defined __STDC__ && __STDC__)
-# define PARAMS(Args) Args
-# else
-# define PARAMS(Args) ()
-# endif
-# endif
-
-# define USE_OBSTACK
-# ifdef USE_OBSTACK
-# include "obstack.h"
-# endif
-
-# define obstack_chunk_alloc malloc
-# define obstack_chunk_free free
-
-struct hash_ent
+struct hash_entry
{
- void *key;
- struct hash_ent *next;
+ void *data;
+ struct hash_entry *next;
};
-typedef struct hash_ent HASH_ENT;
-
-/* This is particularly useful to cast uses in hash_initialize of the
- system free function. */
-typedef void (*Hash_key_freer_type) PARAMS((void *key));
-struct HT
+struct hash_table
{
- /* User-supplied function for freeing keys. It is specified in
- hash_initialize. If non-null, it is used by hash_free and
- hash_clear. You should specify `free' here only if you want
- these functions to free all of your `key' data. This is typically
- the case when your key is simply an auxilliary struct that you
- have malloc'd to aggregate several values. */
- Hash_key_freer_type hash_key_freer;
-
- /* User-supplied hash function that hashes entry E to an integer
- in the range 0..TABLE_SIZE-1. */
- unsigned int (*hash_hash) PARAMS((const void *e, unsigned int table_size));
-
- /* User-supplied function that determines whether a new entry is
- unique by comparing the new entry to entries that hashed to the
- same bucket index. It should return zero for a pair of entries
- that compare equal, non-zero otherwise. */
-
- int (*hash_key_comparator) PARAMS((const void *, const void *));
-
- HASH_ENT **hash_table;
- unsigned int hash_table_size;
- unsigned int hash_n_slots_used;
- unsigned int hash_max_chain_length;
-
- /* Gets set when an entry is deleted from a chain of length
- hash_max_chain_length. Indicates that hash_max_chain_length
- may no longer be valid. */
- unsigned int hash_dirty_max_chain_length;
-
- /* Sum of lengths of all chains (not counting any dummy
- header entries). */
- unsigned int hash_n_keys;
-
- /* A linked list of freed HASH_ENT structs.
- FIXME: Perhaps this is unnecessary and we should simply free
- and reallocate such structs. */
- HASH_ENT *hash_free_entry_list;
-
- /* FIXME: comment. */
-# ifdef USE_OBSTACK
- struct obstack ht_obstack;
-# endif
+ /* The array of buckets starts at BUCKET and extends to BUCKET_LIMIT-1,
+ for a possibility of N_BUCKETS. Among those, N_BUCKETS_USED buckets
+ are not empty, there are N_ENTRIES active entries in the table. */
+ struct hash_entry *bucket;
+ struct hash_entry *bucket_limit;
+ unsigned int n_buckets;
+ unsigned int n_buckets_used;
+ unsigned int n_entries;
+
+ /* Three functions are given to `hash_initialize', see the documentation
+ block for this function. In a word, HASHER randomizes a user entry
+ into a number up from 0 up to some maximum minus 1; COMPARATOR returns
+ true if two user entries compare equally; and DATA_FREER is the cleanup
+ function for a user entry. */
+ Hash_hasher hasher;
+ Hash_comparator comparator;
+ Hash_data_freer data_freer;
+
+ /* A linked list of freed struct hash_entry structs. */
+ struct hash_entry *free_entry_list;
+
+#if USE_OBSTACK
+ /* Whenever obstacks are used, it is possible to allocate all overflowed
+ entries into a single stack, so they all can be freed in a single
+ operation. It is not clear if the speedup is worth the trouble. */
+ struct obstack entry_stack;
+#endif
};
-typedef struct HT HT;
-
-unsigned int
- hash_get_n_slots_used PARAMS((const HT *ht));
-
-unsigned int
- hash_get_max_chain_length PARAMS((HT *ht));
-
-int
- hash_rehash PARAMS((HT *ht, unsigned int new_table_size));
-
-unsigned int
- hash_get_table_size PARAMS((const HT *ht));
-
-HT *
- hash_initialize PARAMS((unsigned int table_size,
- void (*key_freer) PARAMS((void *key)),
- unsigned int (*hash) PARAMS((const void *,
- unsigned int)),
- int (*equality_tester) PARAMS((const void *,
- const void *))));
-
-unsigned int
- hash_get_n_keys PARAMS((const HT *ht));
-
-int
- hash_query_in_table PARAMS((const HT *ht, const void *e));
-
-void *
- hash_lookup PARAMS((const HT *ht, const void *e));
-
-void *
- hash_insert_if_absent PARAMS((HT *ht,
- const void *e,
- int *failed));
-
-void *
- hash_delete_if_present PARAMS((HT *ht, const void *e));
-
-void
- hash_print_statistics PARAMS((const HT *ht, FILE *stream));
-
-int
- hash_get_statistics PARAMS((const HT *ht, unsigned int *n_slots_used,
- unsigned int *n_keys,
- unsigned int *max_chain_length));
-
-int
- hash_table_ok PARAMS((HT *ht));
-
-void
- hash_do_for_each PARAMS((HT *ht,
- void (*f) PARAMS((void *e, void *aux)),
- void *aux));
-
-int
- hash_do_for_each_2 PARAMS((HT *ht,
- int (*f) PARAMS((void *e, void *aux)),
- void *aux));
-
-int
- hash_do_for_each_in_selected_bucket PARAMS((HT *ht,
- const void *key,
- int (*f) PARAMS((const void *bucket_key,
- void *e,
- void *aux)),
- void *aux));
-
-void
- hash_clear PARAMS((HT *ht));
-
-void
- hash_free PARAMS((HT *ht));
-
-void
- hash_get_key_list PARAMS((const HT *ht,
- unsigned int bufsize,
- void **buf));
-
-void *
- hash_get_first PARAMS((const HT *ht));
-
-void *
- hash_get_next PARAMS((const HT *ht, const void *e));
-
-/* This interface to hash_insert_if_absent is used frequently enough to
- merit a macro here. */
-
-# define HASH_INSERT_NEW_ITEM(Ht, Item, Failp) \
- do \
- { \
- void *_already; \
- _already = hash_insert_if_absent ((Ht), (Item), Failp); \
- assert (_already == NULL); \
- } \
- while (0)
-
-#endif /* HASH_H */
+typedef struct hash_table Hash_table;
+
+/* Information and lookup. */
+unsigned int hash_get_n_buckets PARAMS ((const Hash_table *));
+unsigned int hash_get_n_buckets_used PARAMS ((const Hash_table *));
+unsigned int hash_get_n_entries PARAMS ((const Hash_table *));
+unsigned int hash_get_max_bucket_length PARAMS ((const Hash_table *));
+bool hash_table_ok PARAMS ((const Hash_table *));
+void hash_print_statistics PARAMS ((const Hash_table *, FILE *));
+void *hash_lookup PARAMS ((const Hash_table *, const void *));
+
+/* Walking. */
+void *hash_get_first PARAMS ((const Hash_table *));
+void *hash_get_next PARAMS ((const Hash_table *, const void *));
+unsigned int hash_get_entries PARAMS ((const Hash_table *, void **,
+ unsigned int));
+unsigned int hash_do_for_each PARAMS ((const Hash_table *, Hash_processor,
+ void *));
+
+/* Allocation and clean-up. */
+unsigned int hash_string PARAMS ((const char *, unsigned int));
+Hash_table *hash_initialize PARAMS ((unsigned int, Hash_hasher,
+ Hash_comparator, Hash_data_freer));
+void hash_clear PARAMS ((Hash_table *));
+void hash_free PARAMS ((Hash_table *));
+
+/* Insertion and deletion. */
+bool hash_rehash PARAMS ((Hash_table *, unsigned int));
+void *hash_insert PARAMS ((Hash_table *, const void *, bool *));
+void *hash_delete PARAMS ((Hash_table *, const void *));
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