glibc/intl/plural-eval.c

102 lines
2.7 KiB
C

/* Plural expression evaluation.
Copyright (C) 2000, 2001 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
static unsigned long int plural_eval (struct expression *pexp,
unsigned long int n)
internal_function;
static unsigned long int
internal_function
plural_eval (pexp, n)
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:
return leftarg / rightarg;
case module:
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;
}