intl/plural-exp.h

   1 /* Expression parsing and evaluation for plural form selection.
   2    Copyright (C) 2000-2003, 2005 Free Software Foundation, Inc.
   3    Written by Ulrich Drepper <drepper@cygnus.com>, 2000.
   4
   5    This program is free software; you can redistribute it and/or modify it
   6    under the terms of the GNU Library General Public License as published
   7    by the Free Software Foundation; either version 2, or (at your option)
   8    any later version.
   9
  10    This program is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Library General Public License for more details.
  14
  15    You should have received a copy of the GNU Library General Public
  16    License along with this program; if not, write to the Free Software
  17    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
  18    USA.  */
  19
  20 #ifndef _PLURAL_EXP_H
  21 #define _PLURAL_EXP_H
  22
  23 #ifndef internal_function
  24 # define internal_function
  25 #endif
  26
  27 #ifndef attribute_hidden
  28 # define attribute_hidden
  29 #endif
  30
  31
  32 /* This is the representation of the expressions to determine the
  33    plural form.  */
  34 struct expression
  35 {
  36   int nargs;                    /* Number of arguments.  */
  37   enum operator
  38   {
  39     /* Without arguments:  */
  40     var,                        /* The variable "n".  */
  41     num,                        /* Decimal number.  */
  42     /* Unary operators:  */
  43     lnot,                       /* Logical NOT.  */
  44     /* Binary operators:  */
  45     mult,                       /* Multiplication.  */
  46     divide,                     /* Division.  */
  47     module,                     /* Modulo operation.  */
  48     plus,                       /* Addition.  */
  49     minus,                      /* Subtraction.  */
  50     less_than,                  /* Comparison.  */
  51     greater_than,               /* Comparison.  */
  52     less_or_equal,              /* Comparison.  */
  53     greater_or_equal,           /* Comparison.  */
  54     equal,                      /* Comparison for equality.  */
  55     not_equal,                  /* Comparison for inequality.  */
  56     land,                       /* Logical AND.  */
  57     lor,                        /* Logical OR.  */
  58     /* Ternary operators:  */
  59     qmop                        /* Question mark operator.  */
  60   } operation;
  61   union
  62   {
  63     unsigned long int num;      /* Number value for `num'.  */
  64     struct expression *args[3]; /* Up to three arguments.  */
  65   } val;
  66 };
  67
  68 /* This is the data structure to pass information to the parser and get
  69    the result in a thread-safe way.  */
  70 struct parse_args
  71 {
  72   const char *cp;
  73   struct expression *res;
  74 };
  75
  76
  77 /* Names for the libintl functions are a problem.  This source code is used
  78    1. in the GNU C Library library,
  79    2. in the GNU libintl library,
  80    3. in the GNU gettext tools.
  81    The function names in each situation must be different, to allow for
  82    binary incompatible changes in 'struct expression'.  Furthermore,
  83    1. in the GNU C Library library, the names have a __ prefix,
  84    2.+3. in the GNU libintl library and in the GNU gettext tools, the names
  85          must follow ANSI C and not start with __.
  86    So we have to distinguish the three cases.  */
  87 #ifdef _LIBC
  88 # define FREE_EXPRESSION __gettext_free_exp
  89 # define PLURAL_PARSE __gettextparse
  90 # define GERMANIC_PLURAL __gettext_germanic_plural
  91 # define EXTRACT_PLURAL_EXPRESSION __gettext_extract_plural
  92 #elif defined (IN_LIBINTL)
  93 # define FREE_EXPRESSION libintl_gettext_free_exp
  94 # define PLURAL_PARSE libintl_gettextparse
  95 # define GERMANIC_PLURAL libintl_gettext_germanic_plural
  96 # define EXTRACT_PLURAL_EXPRESSION libintl_gettext_extract_plural
  97 #else
  98 # define FREE_EXPRESSION free_plural_expression
  99 # define PLURAL_PARSE parse_plural_expression
 100 # define GERMANIC_PLURAL germanic_plural
 101 # define EXTRACT_PLURAL_EXPRESSION extract_plural_expression
 102 #endif
 103
 104 extern void FREE_EXPRESSION (struct expression *exp)
 105      internal_function;
 106 extern int PLURAL_PARSE (void *arg);
 107 extern struct expression GERMANIC_PLURAL attribute_hidden;
 108 extern void EXTRACT_PLURAL_EXPRESSION (const char *nullentry,
 109                                        struct expression **pluralp,
 110                                        unsigned long int *npluralsp)
 111      internal_function;
 112
 113 #if !defined (_LIBC) && !defined (IN_LIBINTL) && !defined (IN_LIBGLOCALE)
 114 extern unsigned long int plural_eval (struct expression *pexp,
 115                                       unsigned long int n);
 116 #endif
 117
 118 #endif /* _PLURAL_EXP_H */