1  /* Expression parsing and evaluation for plural form selection.
       2     Copyright (C) 2000-2023 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
       6     it under the terms of the GNU Lesser General Public License as published by
       7     the Free Software Foundation; either version 2.1 of the License, or
       8     (at your option) 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
      13     GNU Lesser General Public License for more details.
      14  
      15     You should have received a copy of the GNU Lesser General Public License
      16     along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
      17  
      18  #ifndef _PLURAL_EXP_H
      19  #define _PLURAL_EXP_H
      20  
      21  #ifndef attribute_hidden
      22  # define attribute_hidden
      23  #endif
      24  
      25  #ifdef __cplusplus
      26  extern "C" {
      27  #endif
      28  
      29  
      30  enum expression_operator
      31  {
      32    /* Without arguments:  */
      33    var,				/* The variable "n".  */
      34    num,				/* Decimal number.  */
      35    /* Unary operators:  */
      36    lnot,				/* Logical NOT.  */
      37    /* Binary operators:  */
      38    mult,				/* Multiplication.  */
      39    divide,			/* Division.  */
      40    module,			/* Modulo operation.  */
      41    plus,				/* Addition.  */
      42    minus,			/* Subtraction.  */
      43    less_than,			/* Comparison.  */
      44    greater_than,			/* Comparison.  */
      45    less_or_equal,		/* Comparison.  */
      46    greater_or_equal,		/* Comparison.  */
      47    equal,			/* Comparison for equality.  */
      48    not_equal,			/* Comparison for inequality.  */
      49    land,				/* Logical AND.  */
      50    lor,				/* Logical OR.  */
      51    /* Ternary operators:  */
      52    qmop				/* Question mark operator.  */
      53  };
      54  
      55  /* This is the representation of the expressions to determine the
      56     plural form.  */
      57  struct expression
      58  {
      59    int nargs;			/* Number of arguments.  */
      60    enum expression_operator 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) attribute_hidden;
     105  extern int PLURAL_PARSE (struct parse_args *arg);
     106  extern const struct expression GERMANIC_PLURAL attribute_hidden;
     107  extern void EXTRACT_PLURAL_EXPRESSION (const char *nullentry,
     108  				       const struct expression **pluralp,
     109  				       unsigned long int *npluralsp)
     110       attribute_hidden;
     111  
     112  #if !defined (_LIBC) && !defined (IN_LIBINTL) && !defined (IN_LIBGLOCALE)
     113  extern unsigned long int plural_eval (const struct expression *pexp,
     114  				      unsigned long int n);
     115  #endif
     116  
     117  
     118  #ifdef __cplusplus
     119  }
     120  #endif
     121  
     122  #endif /* _PLURAL_EXP_H */