29 lines
697 B
C
29 lines
697 B
C
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/*
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* (c) copyright 1987 by the Vrije Universiteit, Amsterdam, The Netherlands.
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* See the copyright notice in the ACK home directory, in the file "Copyright".
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*/
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/* $Header$ */
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#include <stdlib.h>
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void *
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bsearch(register const void *key, register const void *base,
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register size_t nmemb, register size_t size,
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int (*compar)(const void *, const void *))
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{
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register const void *mid_point;
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register int cmp;
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while (nmemb > 0) {
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mid_point = (char *)base + size * (nmemb >> 1);
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if ((cmp = (*compar)(key, mid_point)) == 0)
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return (void *)mid_point;
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if (cmp >= 0) {
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base = (char *)mid_point + size;
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nmemb = (nmemb - 1) >> 1;
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} else
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nmemb >>= 1;
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}
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return (void *)NULL;
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}
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