1/*********************************************************************** 2* * 3* This software is part of the ast package * 4* Copyright (c) 1985-2011 AT&T Intellectual Property * 5* and is licensed under the * 6* Eclipse Public License, Version 1.0 * 7* by AT&T Intellectual Property * 8* * 9* A copy of the License is available at * 10* http://www.eclipse.org/org/documents/epl-v10.html * 11* (with md5 checksum b35adb5213ca9657e911e9befb180842) * 12* * 13* Information and Software Systems Research * 14* AT&T Research * 15* Florham Park NJ * 16* * 17* Glenn Fowler <gsf@research.att.com> * 18* David Korn <dgk@research.att.com> * 19* Phong Vo <kpv@research.att.com> * 20* * 21***********************************************************************/ 22#pragma prototyped 23/* 24 * Glenn Fowler 25 * AT&T Bell Laboratories 26 * 27 * hash table library 28 */ 29 30#include "hashlib.h" 31 32/* 33 * return a running 32 bit checksum of string s 34 * 35 * c is the return value from a previous 36 * memsum() or strsum() call, 0 on the first call 37 * 38 * the result is the same on all implementations 39 */ 40 41unsigned long 42strsum(const char* as, register unsigned long c) 43{ 44 register const unsigned char* s = (const unsigned char*)as; 45 register int n; 46 47 while (n = *s++) HASHPART(c, n); 48#if LONG_MAX > 2147483647 49 return(c & 0xffffffff); 50#else 51 return(c); 52#endif 53} 54