ashash.c

来自「开放源码的编译器open watcom 1.6.0版的源代码」· C语言 代码 · 共 52 行

/****************************************************************************
*
*                            Open Watcom Project
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*    Portions Copyright (c) 1983-2002 Sybase, Inc. All Rights Reserved.
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*  ========================================================================
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*    This file contains Original Code and/or Modifications of Original
*    Code as defined in and that are subject to the Sybase Open Watcom
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* Description:  WHEN YOU FIGURE OUT WHAT THIS FILE DOES, PLEASE
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****************************************************************************/


#include "as.h"

extern uint_32 AsHashVal( const char *string, uint_32 size ) {
//************************************************************
// Standard hashPJW from the Dragon Book

    const char          *p;
    unsigned long       g, h;

    h = 0;
    for( p = string; *p; p++ ) {
        h = ( h << 4 ) + *p;
        if( g = h & 0xf0000000 ) {
            h = h ^ ( g >> 24 );
            h = h ^ g;
        }
    }
    return( h % size );
}