stdio-common/grouping_iterator.h

   1 /* Iterator for grouping a number while scanning it forward.
   2    Copyright (C) 2022-2023 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library 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    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <https://www.gnu.org/licenses/>.  */
  18
  19 #ifndef GROUPING_ITERATOR_H
  20 #define GROUPING_ITERATOR_H
  21
  22 #include <locale.h>
  23 #include <stdbool.h>
  24
  25 struct grouping_iterator
  26 {
  27   /* Number of characters in the current group.  If this reaches zero,
  28      a thousands separator needs to be emittted.  */
  29   unsigned int remaining_in_current_group;
  30
  31   /* Number of characters remaining in the number.  This is used to
  32      detect the start of the non-repeating groups.  */
  33   unsigned int remaining;
  34
  35   /* Points to the current grouping descriptor.  */
  36   const char *groupings;
  37
  38   /* Total number of characters in the non-repeating groups.  */
  39   unsigned int non_repeating_groups;
  40
  41   /* Number of separators that will be inserted if the whole number is
  42      processed.  (Does not change during iteration.)  */
  43   unsigned int separators;
  44 };
  45
  46 struct __locale_data;
  47
  48 /* Initializes *IT with the data from LOCDATA (which must be for
  49    LC_MONETARY or LC_NUMERIC).  DIGITS is the length of the number.
  50    Returns true if grouping is active, false if not.  */
  51 bool __grouping_iterator_init (struct grouping_iterator *it,
  52                                int category, locale_t loc,
  53                                unsigned int digits) attribute_hidden;
  54
  55 /* Initializes *IT with no grouping information for a string of length
  56    DIGITS, and return false to indicate no grouping.  */
  57 bool __grouping_iterator_init_none (struct grouping_iterator *it,
  58                                     unsigned int digits)
  59   attribute_hidden;
  60
  61 /* Advances to the next character and returns true if a thousands
  62    separator should be inserted before emitting it.  */
  63 bool __grouping_iterator_next (struct grouping_iterator *it);
  64
  65 #endif /* GROUPING_ITERATOR_H */