usr/src/lib/libast/common/include/hashkey.h

   1 /***********************************************************************
   2 *                                                                      *
   3 *               This software is part of the ast package               *
   4 *          Copyright (c) 1985-2010 AT&T Intellectual Property          *
   5 *                      and is licensed under the                       *
   6 *                  Common Public License, Version 1.0                  *
   7 *                    by AT&T Intellectual Property                     *
   8 *                                                                      *
   9 *                A copy of the License is available at                 *
  10 *            http://www.opensource.org/licenses/cpl1.0.txt             *
  11 *         (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9)         *
  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 Research
  26  *
  27  * 1-6 char lower-case keyword -> long hash
  28  * digit args passed as HASHKEYN('2')
  29  */
  30
  31 #ifndef _HASHKEY_H
  32 #define _HASHKEY_H
  33
  34 #define HASHKEYMAX                      6
  35 #define HASHKEYBIT                      5
  36 #define HASHKEYOFF                      ('a'-1)
  37 #define HASHKEYPART(h,c)                (((h)<<HASHKEYBIT)+HASHKEY1(c))
  38
  39 #define HASHKEYN(n)                     ((n)-'0'+'z'+1)
  40
  41 #define HASHKEY1(c1)                    ((c1)-HASHKEYOFF)
  42 #define HASHKEY2(c1,c2)                 HASHKEYPART(HASHKEY1(c1),c2)
  43 #define HASHKEY3(c1,c2,c3)              HASHKEYPART(HASHKEY2(c1,c2),c3)
  44 #define HASHKEY4(c1,c2,c3,c4)           HASHKEYPART(HASHKEY3(c1,c2,c3),c4)
  45 #define HASHKEY5(c1,c2,c3,c4,c5)        HASHKEYPART(HASHKEY4(c1,c2,c3,c4),c5)
  46 #define HASHKEY6(c1,c2,c3,c4,c5,c6)     HASHKEYPART(HASHKEY5(c1,c2,c3,c4,c5),c6)
  47
  48 #define HASHNKEY1(n,c1)                 HASHKEY2((n)+HASHKEYOFF,c1)
  49 #define HASHNKEY2(n,c2,c1)              HASHKEY3((n)+HASHKEYOFF,c2,c1)
  50 #define HASHNKEY3(n,c3,c2,c1)           HASHKEY4((n)+HASHKEYOFF,c3,c2,c1)
  51 #define HASHNKEY4(n,c4,c3,c2,c1)        HASHKEY5((n)+'a',c4,c3,c2,c1)
  52 #define HASHNKEY5(n,c5,c4,c3,c2,c1)     HASHKEY6((n)+'a',c5,c4,c3,c2,c1)
  53
  54 #if _BLD_ast && defined(__EXPORT__)
  55 #define extern          __EXPORT__
  56 #endif
  57
  58 extern long     strkey(const char*);
  59
  60 #undef  extern
  61
  62 #endif