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*
*                            Open Watcom Project
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*    Portions Copyright (c) 1983-2002 Sybase, Inc. All Rights Reserved.
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* Description:  WHEN YOU FIGURE OUT WHAT THIS FILE DOES, PLEASE
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****************************************************************************/


#include "variety.h"
#undef __INLINE_FUNCTIONS__
#include <stddef.h>
#include <stdlib.h>
#include "extfunc.h"

/*
    The old bsearch could SIGSEGV if the compare is done on elements
    which are not within the given segment.  The error occurs if the search
    key is larger than the 'high' element (or lower than the 'low' member)
    and 'low','mid' and 'high' are all equal (either from the start or
    after several iterations).
*/

typedef int bcomp();
#if defined(_M_IX86)
    #pragma aux (__outside_CLIB) bcomp;
#endif

_WCRTLINK void * bsearch( const void * key,
                const void * base,
                size_t nmemb,
                size_t size,
                int (*cmp)() )
    {
        char *low;
        char *high;
        char *mid;
        int cond;
        bcomp *compar = cmp;

        if( nmemb == 0 ) {
            return( NULL );
        }
        low = (char *) base;
        high = low + (nmemb-1) * size;
// JBS  while( low <= high ) {
        while( low < high ) {
            mid = low + ( (high-low)/size/2 ) * size;
            cond = (*compar)( key, mid );
            if( cond == 0 ) return( mid );
            if( cond < 0 ) {    /* key < mid */
// JBS          high = mid - size;
                high = mid;
            } else {            /* key > mid */
                low = mid + size;
            }
        }
        if (low == high) return( (*compar)(key, low) ? NULL : low );
        return( NULL );
    }