rexx/lstring/hashvalu.c

   1 /*
   2  * $Header$
   3  * $Log$
   4  * Revision 1.1  2001/04/04 05:43:37  wang
   5  * First commit: compiles on Linux, Amiga, Windows, Windows CE, generic gcc
   6  *
   7  * Revision 1.2  1999/11/26 09:56:55  bnv
   8  * Added: Error message fror CE
   9  *
  10  * Revision 1.1  1998/07/02 17:18:00  bnv
  11  * Initial Version
  12  *
  13  */
  14
  15 #include <lstring.h>
  16
  17 /* --------------- Lhashvalue ------------------ */
  18 word
  19 Lhashvalue( const PLstr str )
  20 {
  21 #ifdef WCE
  22 #       error "Lhashvalue is not used!"
  23 #endif
  24         word    value = 0;
  25         size_t  i,l = 0;
  26
  27         if (LISNULL(*str)) return 0;
  28
  29         switch (LTYPE(*str)) {
  30                 case LINTEGER_TY: l = sizeof(long); break;
  31                 case LREAL_TY:    l = sizeof(double); break;
  32                 case LSTRING_TY:  l = MIN(255,LLEN(*str)); break;
  33         }
  34         for (i=0; i<l; i++) {
  35                 value ^= LSTR(*str)[i];
  36 #ifdef __BORLANDC__
  37                 value = _rotl(value,1);
  38 #else
  39                 value = ((value>>1) | (value<<7)) & 0xFF;
  40 #endif
  41         }
  42         return value;
  43 } /* Lhashvalue */