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/* hashlib.h -- the data structures used in hashing in Bash. */
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/* Copyright (C) 1993-2009 Free Software Foundation, Inc.
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This file is part of GNU Bash, the Bourne Again SHell.
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Bash is free software: you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation, either version 3 of the License, or
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(at your option) any later version.
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Bash is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with Bash. If not, see <http://www.gnu.org/licenses/>.
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#if !defined (_HASHLIB_H_)
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typedef struct bucket_contents {
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struct bucket_contents *next; /* Link to next hashed key in this bucket. */
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char *key; /* What we look up. */
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PTR_T data; /* What we really want. */
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unsigned int khash; /* What key hashes to */
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int times_found; /* Number of times this item has been found. */
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typedef struct hash_table {
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BUCKET_CONTENTS **bucket_array; /* Where the data is kept. */
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int nbuckets; /* How many buckets does this table have. */
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int nentries; /* How many entries does this table have. */
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typedef int hash_wfunc __P((BUCKET_CONTENTS *));
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/* Operations on tables as a whole */
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extern HASH_TABLE *hash_create __P((int));
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extern HASH_TABLE *hash_copy __P((HASH_TABLE *, sh_string_func_t *));
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extern void hash_flush __P((HASH_TABLE *, sh_free_func_t *));
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extern void hash_dispose __P((HASH_TABLE *));
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extern void hash_walk __P((HASH_TABLE *, hash_wfunc *));
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/* Operations to extract information from or pieces of tables */
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extern int hash_bucket __P((const char *, HASH_TABLE *));
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extern int hash_size __P((HASH_TABLE *));
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/* Operations on hash table entries */
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extern BUCKET_CONTENTS *hash_search __P((const char *, HASH_TABLE *, int));
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extern BUCKET_CONTENTS *hash_insert __P((char *, HASH_TABLE *, int));
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extern BUCKET_CONTENTS *hash_remove __P((const char *, HASH_TABLE *, int));
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extern unsigned int hash_string __P((const char *));
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/* Redefine the function as a macro for speed. */
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#define hash_items(bucket, table) \
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((table && (bucket < table->nbuckets)) ? \
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table->bucket_array[bucket] : \
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(BUCKET_CONTENTS *)NULL)
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/* Default number of buckets in the hash table. */
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#define DEFAULT_HASH_BUCKETS 128 /* must be power of two */
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#define HASH_ENTRIES(ht) ((ht) ? (ht)->nentries : 0)
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/* flags for hash_search and hash_insert */
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#define HASH_NOSRCH 0x01
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#define HASH_CREATE 0x02
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# if defined (__STDC__)
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# define NULL ((void *) 0)
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# endif /* !__STDC__ */
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#endif /* _HASHLIB_H */