14887Schin /*********************************************************************** 24887Schin * * 34887Schin * This software is part of the ast package * 4*12068SRoger.Faulkner@Oracle.COM * Copyright (c) 1985-2010 AT&T Intellectual Property * 54887Schin * and is licensed under the * 64887Schin * Common Public License, Version 1.0 * 78462SApril.Chin@Sun.COM * by AT&T Intellectual Property * 84887Schin * * 94887Schin * A copy of the License is available at * 104887Schin * http://www.opensource.org/licenses/cpl1.0.txt * 114887Schin * (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9) * 124887Schin * * 134887Schin * Information and Software Systems Research * 144887Schin * AT&T Research * 154887Schin * Florham Park NJ * 164887Schin * * 174887Schin * Glenn Fowler <gsf@research.att.com> * 184887Schin * David Korn <dgk@research.att.com> * 194887Schin * Phong Vo <kpv@research.att.com> * 204887Schin * * 214887Schin ***********************************************************************/ 224887Schin #pragma prototyped 234887Schin /* 244887Schin * Glenn Fowler 254887Schin * AT&T Bell Laboratories 264887Schin * 274887Schin * hash table library 284887Schin */ 294887Schin 304887Schin #include "hashlib.h" 314887Schin 324887Schin /* 334887Schin * return a running 32 bit checksum of buffer b of length n 344887Schin * 354887Schin * c is the return value from a previous 364887Schin * memsum() or strsum() call, 0 on the first call 374887Schin * 384887Schin * the result is the same on all implementations 394887Schin */ 404887Schin 414887Schin unsigned long memsum(const void * ap,int n,register unsigned long c)424887Schinmemsum(const void* ap, int n, register unsigned long c) 434887Schin { 444887Schin register const unsigned char* p = (const unsigned char*)ap; 454887Schin register const unsigned char* e = p + n; 464887Schin 474887Schin while (p < e) HASHPART(c, *p++); 484887Schin #if LONG_MAX > 2147483647 494887Schin return(c & 0xffffffff); 504887Schin #else 514887Schin return(c); 524887Schin #endif 534887Schin } 54