gnu/dist/grep/intl/plural-exp.h

   1 /*      $NetBSD$        */
   2
   3 /* Expression parsing and evaluation for plural form selection.
   4    Copyright (C) 2000, 2001 Free Software Foundation, Inc.
   5    Written by Ulrich Drepper <drepper@cygnus.com>, 2000.
   6
   7    This program is free software; you can redistribute it and/or modify it
   8    under the terms of the GNU Library General Public License as published
   9    by the Free Software Foundation; either version 2, or (at your option)
  10    any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15    Library General Public License for more details.
  16
  17    You should have received a copy of the GNU Library General Public
  18    License along with this program; if not, write to the Free Software
  19    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
  20    USA.  */
  21
  22 #ifndef _PLURAL_EXP_H
  23 #define _PLURAL_EXP_H
  24
  25 #ifndef PARAMS
  26 # if __STDC__ || defined __GNUC__ || defined __SUNPRO_C || defined __cplusplus || __PROTOTYPES
  27 #  define PARAMS(args) args
  28 # else
  29 #  define PARAMS(args) ()
  30 # endif
  31 #endif
  32
  33 #ifndef internal_function
  34 # define internal_function
  35 #endif
  36
  37
  38 /* This is the representation of the expressions to determine the
  39    plural form.  */
  40 struct expression
  41 {
  42   int nargs;                    /* Number of arguments.  */
  43   enum operator
  44   {
  45     /* Without arguments:  */
  46     var,                        /* The variable "n".  */
  47     num,                        /* Decimal number.  */
  48     /* Unary operators:  */
  49     lnot,                       /* Logical NOT.  */
  50     /* Binary operators:  */
  51     mult,                       /* Multiplication.  */
  52     divide,                     /* Division.  */
  53     module,                     /* Modulo operation.  */
  54     plus,                       /* Addition.  */
  55     minus,                      /* Subtraction.  */
  56     less_than,                  /* Comparison.  */
  57     greater_than,               /* Comparison.  */
  58     less_or_equal,              /* Comparison.  */
  59     greater_or_equal,           /* Comparison.  */
  60     equal,                      /* Comparison for equality.  */
  61     not_equal,                  /* Comparison for inequality.  */
  62     land,                       /* Logical AND.  */
  63     lor,                        /* Logical OR.  */
  64     /* Ternary operators:  */
  65     qmop                        /* Question mark operator.  */
  66   } operation;
  67   union
  68   {
  69     unsigned long int num;      /* Number value for `num'.  */
  70     struct expression *args[3]; /* Up to three arguments.  */
  71   } val;
  72 };
  73
  74 /* This is the data structure to pass information to the parser and get
  75    the result in a thread-safe way.  */
  76 struct parse_args
  77 {
  78   const char *cp;
  79   struct expression *res;
  80 };
  81
  82
  83 /* Names for the libintl functions are a problem.  This source code is used
  84    1. in the GNU C Library library,
  85    2. in the GNU libintl library,
  86    3. in the GNU gettext tools.
  87    The function names in each situation must be different, to allow for
  88    binary incompatible changes in 'struct expression'.  Furthermore,
  89    1. in the GNU C Library library, the names have a __ prefix,
  90    2.+3. in the GNU libintl library and in the GNU gettext tools, the names
  91          must follow ANSI C and not start with __.
  92    So we have to distinguish the three cases.  */
  93 #ifdef _LIBC
  94 # define FREE_EXPRESSION __gettext_free_exp
  95 # define PLURAL_PARSE __gettextparse
  96 # define GERMANIC_PLURAL __gettext_germanic_plural
  97 # define EXTRACT_PLURAL_EXPRESSION __gettext_extract_plural
  98 #elif defined (IN_LIBINTL)
  99 # define FREE_EXPRESSION gettext_free_exp__
 100 # define PLURAL_PARSE gettextparse__
 101 # define GERMANIC_PLURAL gettext_germanic_plural__
 102 # define EXTRACT_PLURAL_EXPRESSION gettext_extract_plural__
 103 #else
 104 # define FREE_EXPRESSION free_plural_expression
 105 # define PLURAL_PARSE parse_plural_expression
 106 # define GERMANIC_PLURAL germanic_plural
 107 # define EXTRACT_PLURAL_EXPRESSION extract_plural_expression
 108 #endif
 109
 110 extern void FREE_EXPRESSION PARAMS ((struct expression *exp))
 111      internal_function;
 112 extern int PLURAL_PARSE PARAMS ((void *arg));
 113 extern struct expression GERMANIC_PLURAL;
 114 extern void EXTRACT_PLURAL_EXPRESSION PARAMS ((const char *nullentry,
 115                                                struct expression **pluralp,
 116                                                unsigned long int *npluralsp))
 117      internal_function;
 118
 119 #if !defined (_LIBC) && !defined (IN_LIBINTL)
 120 extern unsigned long int plural_eval PARAMS ((struct expression *pexp,
 121                                               unsigned long int n));
 122 #endif
 123
 124 #endif /* _PLURAL_EXP_H */