nasm/include/hashtbl.h
H. Peter Anvin 5253f58c36 Add generic perfect string hashes, use for directives
Add a generic facility for generating perfect string hashes, where all
that is needed is an enum and a string table.  The existing mechanism
using a custom Perl script wrapped around a module continues to be
available for any use case where this particular approach isn't
sophisticated enough.

Much of this patch comes from renaming "enum directives" to "enum
directive" as a result of the string hash generator expecting a set of
uniform naming conventions.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2017-04-03 00:27:07 -07:00

86 lines
2.9 KiB
C

/* ----------------------------------------------------------------------- *
*
* Copyright 1996-2017 The NASM Authors - All Rights Reserved
* See the file AUTHORS included with the NASM distribution for
* the specific copyright holders.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following
* conditions are met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials provided
* with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
* CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
* EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* ----------------------------------------------------------------------- */
/*
* hashtbl.h
*
* Efficient dictionary hash table class.
*/
#ifndef NASM_HASHTBL_H
#define NASM_HASHTBL_H
#include <stddef.h>
#include "nasmlib.h"
struct hash_tbl_node {
uint64_t hash;
const char *key;
void *data;
};
struct hash_table {
struct hash_tbl_node *table;
size_t load;
size_t size;
size_t max_load;
};
struct hash_insert {
uint64_t hash;
struct hash_table *head;
struct hash_tbl_node *where;
};
uint64_t crc64(uint64_t crc, const char *string);
uint64_t crc64i(uint64_t crc, const char *string);
#define CRC64_INIT UINT64_C(0xffffffffffffffff)
/* Some reasonable initial sizes... */
#define HASH_SMALL 4
#define HASH_MEDIUM 16
#define HASH_LARGE 256
void hash_init(struct hash_table *head, size_t size);
void **hash_find(struct hash_table *head, const char *string,
struct hash_insert *insert);
void **hash_findi(struct hash_table *head, const char *string,
struct hash_insert *insert);
void **hash_add(struct hash_insert *insert, const char *string, void *data);
void *hash_iterate(const struct hash_table *head,
struct hash_tbl_node **iterator,
const char **key);
void hash_free(struct hash_table *head);
#endif /* NASM_HASHTBL_H */