/* hash - hashing table processing.
- Copyright (C) 1998, 1999 Free Software Foundation, Inc.
+ Copyright (C) 1998-1999, 2001, 2003, 2009-2014 Free Software Foundation,
+ Inc.
Written by Jim Meyering <meyering@ascend.com>, 1998.
- This program is free software; you can redistribute it and/or modify
+ 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.
+ the Free Software Foundation; either version 3 of the License, 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
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. */
+ along with this program. If not, see <http://www.gnu.org/licenses/>. */
/* 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. */
+ obstacks instead of malloc, and recompile 'hash.c' with same setting. */
-#ifndef PARAMS
-# if PROTOTYPES || __STDC__
-# define PARAMS(Args) Args
+#ifndef HASH_H_
+# define HASH_H_
+
+# include <stdio.h>
+# include <stdbool.h>
+
+/* The __attribute__ feature is available in gcc versions 2.5 and later.
+ The warn_unused_result attribute appeared first in gcc-3.4.0. */
+# if __GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ >= 4)
+# define _GL_ATTRIBUTE_WUR __attribute__ ((__warn_unused_result__))
# else
-# define PARAMS(Args) ()
+# define _GL_ATTRIBUTE_WUR /* empty */
# endif
-#endif
-typedef unsigned (*Hash_hasher) PARAMS ((const void *, unsigned));
-typedef bool (*Hash_comparator) PARAMS ((const void *, const void *));
-typedef void (*Hash_data_freer) PARAMS ((void *));
-typedef bool (*Hash_processor) PARAMS ((void *, void *));
+# ifndef _GL_ATTRIBUTE_DEPRECATED
+/* The __attribute__((__deprecated__)) feature
+ is available in gcc versions 3.1 and newer. */
+# if __GNUC__ < 3 || (__GNUC__ == 3 && __GNUC_MINOR__ < 1)
+# define _GL_ATTRIBUTE_DEPRECATED /* empty */
+# else
+# define _GL_ATTRIBUTE_DEPRECATED __attribute__ ((__deprecated__))
+# endif
+# endif
-struct hash_entry
- {
- void *data;
- struct hash_entry *next;
- };
+typedef size_t (*Hash_hasher) (const void *, size_t);
+typedef bool (*Hash_comparator) (const void *, const void *);
+typedef void (*Hash_data_freer) (void *);
+typedef bool (*Hash_processor) (void *, void *);
struct hash_tuning
{
- /* This structure is mainly used for `hash_initialize', see the block
- documentation of `hash_reset_tuning' for more complete comments. */
-
- float shrink_threshold; /* ratio of used buckets to trigger a shrink */
- float shrink_factor; /* ratio of new smaller size to original size */
- float growth_threshold; /* ratio of used buckets to trigger a growth */
- float growth_factor; /* ratio of new bigger size to original size */
- bool is_n_buckets; /* if CANDIDATE really means table size */
+ /* This structure is mainly used for 'hash_initialize', see the block
+ documentation of 'hash_reset_tuning' for more complete comments. */
+
+ float shrink_threshold; /* ratio of used buckets to trigger a shrink */
+ float shrink_factor; /* ratio of new smaller size to original size */
+ float growth_threshold; /* ratio of used buckets to trigger a growth */
+ float growth_factor; /* ratio of new bigger size to original size */
+ bool is_n_buckets; /* if CANDIDATE really means table size */
};
typedef struct hash_tuning Hash_tuning;
-struct hash_table
- {
- /* 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 n_buckets;
- unsigned n_buckets_used;
- unsigned n_entries;
-
- /* Tuning arguments, kept in a physicaly separate structure. */
- const Hash_tuning *tuning;
-
- /* 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
- };
+struct hash_table;
typedef struct hash_table Hash_table;
/* Information and lookup. */
-unsigned hash_get_n_buckets PARAMS ((const Hash_table *));
-unsigned hash_get_n_buckets_used PARAMS ((const Hash_table *));
-unsigned hash_get_n_entries PARAMS ((const Hash_table *));
-unsigned 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 *));
+size_t hash_get_n_buckets (const Hash_table *) _GL_ATTRIBUTE_PURE;
+size_t hash_get_n_buckets_used (const Hash_table *) _GL_ATTRIBUTE_PURE;
+size_t hash_get_n_entries (const Hash_table *) _GL_ATTRIBUTE_PURE;
+size_t hash_get_max_bucket_length (const Hash_table *) _GL_ATTRIBUTE_PURE;
+bool hash_table_ok (const Hash_table *) _GL_ATTRIBUTE_PURE;
+void hash_print_statistics (const Hash_table *, FILE *);
+void *hash_lookup (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 hash_get_entries PARAMS ((const Hash_table *, void **, unsigned));
-unsigned hash_do_for_each PARAMS ((const Hash_table *, Hash_processor, void *));
+void *hash_get_first (const Hash_table *) _GL_ATTRIBUTE_PURE;
+void *hash_get_next (const Hash_table *, const void *);
+size_t hash_get_entries (const Hash_table *, void **, size_t);
+size_t hash_do_for_each (const Hash_table *, Hash_processor, void *);
/* Allocation and clean-up. */
-unsigned hash_string PARAMS ((const char *, unsigned));
-void hash_reset_tuning PARAMS ((Hash_tuning *));
-Hash_table *hash_initialize PARAMS ((unsigned, const Hash_tuning *,
- Hash_hasher, Hash_comparator,
- Hash_data_freer));
-void hash_clear PARAMS ((Hash_table *));
-void hash_free PARAMS ((Hash_table *));
+size_t hash_string (const char *, size_t) _GL_ATTRIBUTE_PURE;
+void hash_reset_tuning (Hash_tuning *);
+Hash_table *hash_initialize (size_t, const Hash_tuning *,
+ Hash_hasher, Hash_comparator,
+ Hash_data_freer) _GL_ATTRIBUTE_WUR;
+void hash_clear (Hash_table *);
+void hash_free (Hash_table *);
/* Insertion and deletion. */
-bool hash_rehash PARAMS ((Hash_table *, unsigned));
-void *hash_insert PARAMS ((Hash_table *, const void *));
-void *hash_delete PARAMS ((Hash_table *, const void *));
+bool hash_rehash (Hash_table *, size_t) _GL_ATTRIBUTE_WUR;
+void *hash_insert (Hash_table *, const void *) _GL_ATTRIBUTE_WUR;
+
+/* Deprecate this interface. It has been renamed to hash_insert_if_absent. */
+int hash_insert0 (Hash_table *table, /* FIXME: remove in 2013 */
+ const void *entry,
+ const void **matched_ent) _GL_ATTRIBUTE_DEPRECATED;
+int hash_insert_if_absent (Hash_table *table, const void *entry,
+ const void **matched_ent);
+void *hash_delete (Hash_table *, const void *);
+
+#endif
projects / gnulib.git / blobdiff