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/* $OpenBSD: lsearch.c,v 1.5 2014/07/18 04:16:09 matthew Exp $ */ |
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/* |
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* Copyright (c) 1989, 1993 |
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* The Regents of the University of California. All rights reserved. |
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* |
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* This code is derived from software contributed to Berkeley by |
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* Roger L. Snyder. |
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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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* 3. Neither the name of the University nor the names of its contributors |
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* may be used to endorse or promote products derived from this software |
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* without specific prior written permission. |
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* |
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* THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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/types.h> |
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#include <string.h> |
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#include <search.h> |
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typedef int (*cmp_fn_t)(const void *, const void *); |
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static void *linear_base(const void *, const void *, size_t *, size_t, |
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cmp_fn_t, int); |
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void * |
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lsearch(const void *key, void *base, size_t *nelp, size_t width, |
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cmp_fn_t compar) |
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{ |
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return(linear_base(key, base, nelp, width, compar, 1)); |
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} |
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void * |
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lfind(const void *key, const void *base, size_t *nelp, size_t width, |
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cmp_fn_t compar) |
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{ |
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return(linear_base(key, base, nelp, width, compar, 0)); |
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} |
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static void * |
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linear_base(const void *key, const void *base, size_t *nelp, size_t width, |
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cmp_fn_t compar, int add_flag) |
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{ |
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const char *element, *end; |
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end = (const char *)base + *nelp * width; |
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for (element = base; element < end; element += width) |
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if (!compar(key, element)) /* key found */ |
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return((void *)element); |
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if (!add_flag) /* key not found */ |
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return(NULL); |
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/* |
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* The UNIX System User's Manual, 1986 edition claims that |
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* a NULL pointer is returned by lsearch with errno set |
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* appropriately, if there is not enough room in the table |
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* to add a new item. This can't be done as none of these |
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* routines have any method of determining the size of the |
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* table. This comment isn't in the 1986-87 System V |
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* manual. |
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*/ |
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++*nelp; |
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memcpy((void *)end, key, width); |
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return((void *)end); |
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} |