lib/intl/plural-exp.c

   1 /* plural-exp.c - Expression parsing for plural form selection. */
   2
   3 /* Copyright (C) 2000, 2001, 2005-2009 Free Software Foundation, Inc.
   4    Written by Ulrich Drepper <drepper@cygnus.com>, 2000.
   5
   6    This file is part of GNU Bash.
   7
   8    Bash is free software: you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation, either version 3 of the License, or
  11    (at your option) any later version.
  12
  13    Bash is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with Bash.  If not, see <http://www.gnu.org/licenses/>.
  20 */
  21
  22 #ifdef HAVE_CONFIG_H
  23 # include <config.h>
  24 #endif
  25
  26 #include <ctype.h>
  27 #include <stdlib.h>
  28 #include <string.h>
  29
  30 #include "plural-exp.h"
  31
  32 #if (defined __GNUC__ && !defined __APPLE_CC__) \
  33     || (defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L)
  34
  35 /* These structs are the constant expression for the germanic plural
  36    form determination.  It represents the expression  "n != 1".  */
  37 static const struct expression plvar =
  38 {
  39   .nargs = 0,
  40   .operation = var,
  41 };
  42 static const struct expression plone =
  43 {
  44   .nargs = 0,
  45   .operation = num,
  46   .val =
  47   {
  48     .num = 1
  49   }
  50 };
  51 struct expression GERMANIC_PLURAL =
  52 {
  53   .nargs = 2,
  54   .operation = not_equal,
  55   .val =
  56   {
  57     .args =
  58     {
  59       [0] = (struct expression *) &plvar,
  60       [1] = (struct expression *) &plone
  61     }
  62   }
  63 };
  64
  65 # define INIT_GERMANIC_PLURAL()
  66
  67 #else
  68
  69 /* For compilers without support for ISO C 99 struct/union initializers:
  70    Initialization at run-time.  */
  71
  72 static struct expression plvar;
  73 static struct expression plone;
  74 struct expression GERMANIC_PLURAL;
  75
  76 static void
  77 init_germanic_plural ()
  78 {
  79   if (plone.val.num == 0)
  80     {
  81       plvar.nargs = 0;
  82       plvar.operation = var;
  83
  84       plone.nargs = 0;
  85       plone.operation = num;
  86       plone.val.num = 1;
  87
  88       GERMANIC_PLURAL.nargs = 2;
  89       GERMANIC_PLURAL.operation = not_equal;
  90       GERMANIC_PLURAL.val.args[0] = &plvar;
  91       GERMANIC_PLURAL.val.args[1] = &plone;
  92     }
  93 }
  94
  95 # define INIT_GERMANIC_PLURAL() init_germanic_plural ()
  96
  97 #endif
  98
  99 void
 100 internal_function
 101 EXTRACT_PLURAL_EXPRESSION (nullentry, pluralp, npluralsp)
 102      const char *nullentry;
 103      struct expression **pluralp;
 104      unsigned long int *npluralsp;
 105 {
 106   if (nullentry != NULL)
 107     {
 108       const char *plural;
 109       const char *nplurals;
 110
 111       plural = strstr (nullentry, "plural=");
 112       nplurals = strstr (nullentry, "nplurals=");
 113       if (plural == NULL || nplurals == NULL)
 114         goto no_plural;
 115       else
 116         {
 117           char *endp;
 118           unsigned long int n;
 119           struct parse_args args;
 120
 121           /* First get the number.  */
 122           nplurals += 9;
 123           while (*nplurals != '\0' && isspace ((unsigned char) *nplurals))
 124             ++nplurals;
 125           if (!(*nplurals >= '0' && *nplurals <= '9'))
 126             goto no_plural;
 127 #if defined HAVE_STRTOUL || defined _LIBC
 128           n = strtoul (nplurals, &endp, 10);
 129 #else
 130           for (endp = nplurals, n = 0; *endp >= '0' && *endp <= '9'; endp++)
 131             n = n * 10 + (*endp - '0');
 132 #endif
 133           if (nplurals == endp)
 134             goto no_plural;
 135           *npluralsp = n;
 136
 137           /* Due to the restrictions bison imposes onto the interface of the
 138              scanner function we have to put the input string and the result
 139              passed up from the parser into the same structure which address
 140              is passed down to the parser.  */
 141           plural += 7;
 142           args.cp = plural;
 143           if (PLURAL_PARSE (&args) != 0)
 144             goto no_plural;
 145           *pluralp = args.res;
 146         }
 147     }
 148   else
 149     {
 150       /* By default we are using the Germanic form: singular form only
 151          for `one', the plural form otherwise.  Yes, this is also what
 152          English is using since English is a Germanic language.  */
 153     no_plural:
 154       INIT_GERMANIC_PLURAL ();
 155       *pluralp = &GERMANIC_PLURAL;
 156       *npluralsp = 2;
 157     }
 158 }