glibc/intl/plural-exp.c

157 lines
4.0 KiB
C

/* Expression parsing for plural form selection.
Copyright (C) 2000-2013 Free Software Foundation, Inc.
Written by Ulrich Drepper <drepper@cygnus.com>, 2000.
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, see
<http://www.gnu.org/licenses/>. */
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include <ctype.h>
#include <stdlib.h>
#include <string.h>
#include "plural-exp.h"
#if (defined __GNUC__ && !defined __APPLE_CC__) \
|| (defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L)
/* These structs are the constant expression for the germanic plural
form determination. It represents the expression "n != 1". */
static const struct expression plvar =
{
.nargs = 0,
.operation = var,
};
static const struct expression plone =
{
.nargs = 0,
.operation = num,
.val =
{
.num = 1
}
};
const struct expression GERMANIC_PLURAL =
{
.nargs = 2,
.operation = not_equal,
.val =
{
.args =
{
[0] = (struct expression *) &plvar,
[1] = (struct expression *) &plone
}
}
};
# define INIT_GERMANIC_PLURAL()
#else
/* For compilers without support for ISO C 99 struct/union initializers:
Initialization at run-time. */
static struct expression plvar;
static struct expression plone;
struct expression GERMANIC_PLURAL;
static void
init_germanic_plural ()
{
if (plone.val.num == 0)
{
plvar.nargs = 0;
plvar.operation = var;
plone.nargs = 0;
plone.operation = num;
plone.val.num = 1;
GERMANIC_PLURAL.nargs = 2;
GERMANIC_PLURAL.operation = not_equal;
GERMANIC_PLURAL.val.args[0] = &plvar;
GERMANIC_PLURAL.val.args[1] = &plone;
}
}
# define INIT_GERMANIC_PLURAL() init_germanic_plural ()
#endif
void
internal_function
EXTRACT_PLURAL_EXPRESSION (nullentry, pluralp, npluralsp)
const char *nullentry;
const struct expression **pluralp;
unsigned long int *npluralsp;
{
if (nullentry != NULL)
{
const char *plural;
const char *nplurals;
plural = strstr (nullentry, "plural=");
nplurals = strstr (nullentry, "nplurals=");
if (plural == NULL || nplurals == NULL)
goto no_plural;
else
{
char *endp;
unsigned long int n;
struct parse_args args;
/* First get the number. */
nplurals += 9;
while (*nplurals != '\0' && isspace ((unsigned char) *nplurals))
++nplurals;
if (!(*nplurals >= '0' && *nplurals <= '9'))
goto no_plural;
#if defined HAVE_STRTOUL || defined _LIBC
n = strtoul (nplurals, &endp, 10);
#else
for (endp = nplurals, n = 0; *endp >= '0' && *endp <= '9'; endp++)
n = n * 10 + (*endp - '0');
#endif
if (nplurals == endp)
goto no_plural;
*npluralsp = n;
/* Due to the restrictions bison imposes onto the interface of the
scanner function we have to put the input string and the result
passed up from the parser into the same structure which address
is passed down to the parser. */
plural += 7;
args.cp = plural;
if (PLURAL_PARSE (&args) != 0)
goto no_plural;
*pluralp = args.res;
}
}
else
{
/* By default we are using the Germanic form: singular form only
for `one', the plural form otherwise. Yes, this is also what
English is using since English is a Germanic language. */
no_plural:
INIT_GERMANIC_PLURAL ();
*pluralp = &GERMANIC_PLURAL;
*npluralsp = 2;
}
}