64 lines
2.3 KiB
C
64 lines
2.3 KiB
C
/*-
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* Copyright (c) 2015 Nuxi, https://nuxi.nl/
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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*
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*/
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#include <sys/cdefs.h>
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//__FBSDID("$FreeBSD$");
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#include "search.h"
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#include <stdlib.h>
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#include "hsearch.h"
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int
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hcreate_r(size_t nel, struct hsearch_data *htab)
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{
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struct __hsearch *hsearch;
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/*
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* Allocate a hash table object. Ignore the provided hint and start
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* off with a table of sixteen entries. In most cases this hint is
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* just a wild guess. Resizing the table dynamically if the use
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* increases a threshold does not affect the worst-case running time.
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*/
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hsearch = malloc(sizeof(*hsearch));
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if (hsearch == NULL)
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return 0;
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hsearch->entries = calloc(16, sizeof(ENTRY));
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if (hsearch->entries == NULL) {
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free(hsearch);
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return 0;
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}
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/*
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* Pick a random initialization for the FNV-1a hashing. This makes it
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* hard to come up with a fixed set of keys to force hash collisions.
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*/
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arc4random_buf(&hsearch->offset_basis, sizeof(hsearch->offset_basis));
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hsearch->index_mask = 0xf;
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hsearch->entries_used = 0;
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htab->__hsearch = hsearch;
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return 1;
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}
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