navit/intl/eval-plural.h

/* Plural expression evaluation.
   Copyright (C) 2000-2003 Free Software Foundation, Inc.

   This program is free software; you can redistribute it and/or modify it
   under the terms of the GNU Library General Public License as published
   by the Free Software Foundation; either version 2, or (at your option)
   any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Library General Public License for more details.

   You should have received a copy of the GNU Library General Public
   License along with this program; if not, write to the Free Software
   Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
   USA.  */

#ifndef STATIC
#define STATIC static
#endif

/* Evaluate the plural expression and return an index value.  */
STATIC
unsigned long int
internal_function
plural_eval (struct expression *pexp, unsigned long int n)
{
  switch (pexp->nargs)
    {
    case 0:
      switch (pexp->operation)
        {
        case var:
          return n;
        case num:
          return pexp->val.num;
        default:
          break;
        }
      /* NOTREACHED */
      break;
    case 1:
      {
        /* pexp->operation must be lnot.  */
        unsigned long int arg = plural_eval (pexp->val.args[0], n);
        return ! arg;
      }
    case 2:
      {
        unsigned long int leftarg = plural_eval (pexp->val.args[0], n);
        if (pexp->operation == lor)
          return leftarg || plural_eval (pexp->val.args[1], n);
        else if (pexp->operation == land)
          return leftarg && plural_eval (pexp->val.args[1], n);
        else
          {
            unsigned long int rightarg = plural_eval (pexp->val.args[1], n);

            switch (pexp->operation)
              {
              case mult:
                return leftarg * rightarg;
              case divide:
#if !INTDIV0_RAISES_SIGFPE
                if (rightarg == 0)
                  raise (SIGFPE);
#endif
                return leftarg / rightarg;
              case module:
#if !INTDIV0_RAISES_SIGFPE
                if (rightarg == 0)
                  raise (SIGFPE);
#endif
                return leftarg % rightarg;
              case plus:
                return leftarg + rightarg;
              case minus:
                return leftarg - rightarg;
              case less_than:
                return leftarg < rightarg;
              case greater_than:
                return leftarg > rightarg;
              case less_or_equal:
                return leftarg <= rightarg;
              case greater_or_equal:
                return leftarg >= rightarg;
              case equal:
                return leftarg == rightarg;
              case not_equal:
                return leftarg != rightarg;
              default:
                break;
              }
          }
        /* NOTREACHED */
        break;
      }
    case 3:
      {
        /* pexp->operation must be qmop.  */
        unsigned long int boolarg = plural_eval (pexp->val.args[0], n);
        return plural_eval (pexp->val.args[boolarg ? 1 : 2], n);
      }
    }
  /* NOTREACHED */
  return 0;
}
1	zoff99	2	/* Plural expression evaluation.
2			Copyright (C) 2000-2003 Free Software Foundation, Inc.
3
4			This program is free software; you can redistribute it and/or modify it
5			under the terms of the GNU Library General Public License as published
6			by the Free Software Foundation; either version 2, or (at your option)
7			any later version.
8
9			This program is distributed in the hope that it will be useful,
10			but WITHOUT ANY WARRANTY; without even the implied warranty of
11			MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12			Library General Public License for more details.
13
14			You should have received a copy of the GNU Library General Public
15			License along with this program; if not, write to the Free Software
16			Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
17			USA. */
18
19			#ifndef STATIC
20			#define STATIC static
21			#endif
22
23			/* Evaluate the plural expression and return an index value. */
24			STATIC
25			unsigned long int
26			internal_function
27			plural_eval (struct expression *pexp, unsigned long int n)
28			{
29			switch (pexp->nargs)
30			{
31			case 0:
32			switch (pexp->operation)
33			{
34			case var:
35			return n;
36			case num:
37			return pexp->val.num;
38			default:
39			break;
40			}
41			/* NOTREACHED */
42			break;
43			case 1:
44			{
45			/* pexp->operation must be lnot. */
46			unsigned long int arg = plural_eval (pexp->val.args[0], n);
47			return ! arg;
48			}
49			case 2:
50			{
51			unsigned long int leftarg = plural_eval (pexp->val.args[0], n);
52			if (pexp->operation == lor)
53			return leftarg \|\| plural_eval (pexp->val.args[1], n);
54			else if (pexp->operation == land)
55			return leftarg && plural_eval (pexp->val.args[1], n);
56			else
57			{
58			unsigned long int rightarg = plural_eval (pexp->val.args[1], n);
59
60			switch (pexp->operation)
61			{
62			case mult:
63			return leftarg * rightarg;
64			case divide:
65			#if !INTDIV0_RAISES_SIGFPE
66			if (rightarg == 0)
67			raise (SIGFPE);
68			#endif
69			return leftarg / rightarg;
70			case module:
71			#if !INTDIV0_RAISES_SIGFPE
72			if (rightarg == 0)
73			raise (SIGFPE);
74			#endif
75			return leftarg % rightarg;
76			case plus:
77			return leftarg + rightarg;
78			case minus:
79			return leftarg - rightarg;
80			case less_than:
81			return leftarg < rightarg;
82			case greater_than:
83			return leftarg > rightarg;
84			case less_or_equal:
85			return leftarg <= rightarg;
86			case greater_or_equal:
87			return leftarg >= rightarg;
88			case equal:
89			return leftarg == rightarg;
90			case not_equal:
91			return leftarg != rightarg;
92			default:
93			break;
94			}
95			}
96			/* NOTREACHED */
97			break;
98			}
99			case 3:
100			{
101			/* pexp->operation must be qmop. */
102			unsigned long int boolarg = plural_eval (pexp->val.args[0], n);
103			return plural_eval (pexp->val.args[boolarg ? 1 : 2], n);
104			}
105			}
106			/* NOTREACHED */
107			return 0;
108			}