stdio-common/_i18n_number.h

   1 /* Copyright (C) 2000-2020 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Ulrich Drepper <drepper@gnu.org>, 2000.
   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 #include <stdbool.h>
  20 #include <wchar.h>
  21 #include <wctype.h>
  22 #include <scratch_buffer.h>
  23
  24 #include "../locale/outdigits.h"
  25 #include "../locale/outdigitswc.h"
  26
  27 static CHAR_T *
  28 _i18n_number_rewrite (CHAR_T *w, CHAR_T *rear_ptr, CHAR_T *end)
  29 {
  30 #ifdef COMPILE_WPRINTF
  31 # define decimal NULL
  32 # define thousands NULL
  33 #else
  34   char decimal[MB_LEN_MAX + 1];
  35   char thousands[MB_LEN_MAX + 1];
  36 #endif
  37
  38   /* "to_outpunct" is a map from ASCII decimal point and thousands-sep
  39      to their equivalent in locale. This is defined for locales which
  40      use extra decimal point and thousands-sep.  */
  41   wctrans_t map = __wctrans ("to_outpunct");
  42   wint_t wdecimal = __towctrans (L'.', map);
  43   wint_t wthousands = __towctrans (L',', map);
  44
  45 #ifndef COMPILE_WPRINTF
  46   if (__glibc_unlikely (map != NULL))
  47     {
  48       mbstate_t state;
  49       memset (&state, '\0', sizeof (state));
  50
  51       size_t n = __wcrtomb (decimal, wdecimal, &state);
  52       if (n == (size_t) -1)
  53         memcpy (decimal, ".", 2);
  54       else
  55         decimal[n] = '\0';
  56
  57       memset (&state, '\0', sizeof (state));
  58
  59       n = __wcrtomb (thousands, wthousands, &state);
  60       if (n == (size_t) -1)
  61         memcpy (thousands, ",", 2);
  62       else
  63         thousands[n] = '\0';
  64     }
  65 #endif
  66
  67   /* Copy existing string so that nothing gets overwritten.  */
  68   CHAR_T *src;
  69   struct scratch_buffer buffer;
  70   scratch_buffer_init (&buffer);
  71   if (!scratch_buffer_set_array_size (&buffer, rear_ptr - w, sizeof (CHAR_T)))
  72     /* If we cannot allocate the memory don't rewrite the string.
  73        It is better than nothing.  */
  74     return w;
  75   src = buffer.data;
  76
  77   CHAR_T *s = (CHAR_T *) __mempcpy (src, w,
  78                                     (rear_ptr - w) * sizeof (CHAR_T));
  79
  80   w = end;
  81
  82   /* Process all characters in the string.  */
  83   while (--s >= src)
  84     {
  85       if (*s >= '0' && *s <= '9')
  86         {
  87           if (sizeof (CHAR_T) == 1)
  88             w = (CHAR_T *) outdigit_value ((char *) w, *s - '0');
  89           else
  90             *--w = (CHAR_T) outdigitwc_value (*s - '0');
  91         }
  92       else if (__builtin_expect (map == NULL, 1) || (*s != '.' && *s != ','))
  93         *--w = *s;
  94       else
  95         {
  96           if (sizeof (CHAR_T) == 1)
  97             {
  98               const char *outpunct = *s == '.' ? decimal : thousands;
  99               size_t dlen = strlen (outpunct);
 100
 101               w -= dlen;
 102               while (dlen-- > 0)
 103                 w[dlen] = outpunct[dlen];
 104             }
 105           else
 106             *--w = *s == '.' ? (CHAR_T) wdecimal : (CHAR_T) wthousands;
 107         }
 108     }
 109
 110   scratch_buffer_free (&buffer);
 111   return w;
 112 }