stdio-common/_i18n_number.h

   1 /* Copyright (C) 2000-2022 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, see
  16    <https://www.gnu.org/licenses/>.  */
  17
  18 #include <stdbool.h>
  19 #include <wchar.h>
  20 #include <wctype.h>
  21 #include <scratch_buffer.h>
  22
  23 #include "../locale/outdigits.h"
  24 #include "../locale/outdigitswc.h"
  25
  26 static CHAR_T *
  27 _i18n_number_rewrite (CHAR_T *w, CHAR_T *rear_ptr, CHAR_T *end)
  28 {
  29 #ifdef COMPILE_WPRINTF
  30 # define decimal NULL
  31 # define thousands NULL
  32 #else
  33   char decimal[MB_LEN_MAX + 1];
  34   char thousands[MB_LEN_MAX + 1];
  35 #endif
  36
  37   /* "to_outpunct" is a map from ASCII decimal point and thousands-sep
  38      to their equivalent in locale. This is defined for locales which
  39      use extra decimal point and thousands-sep.  */
  40   wctrans_t map = __wctrans ("to_outpunct");
  41   wint_t wdecimal = __towctrans (L'.', map);
  42   wint_t wthousands = __towctrans (L',', map);
  43
  44 #ifndef COMPILE_WPRINTF
  45   if (__glibc_unlikely (map != NULL))
  46     {
  47       mbstate_t state;
  48       memset (&state, '\0', sizeof (state));
  49
  50       size_t n = __wcrtomb (decimal, wdecimal, &state);
  51       if (n == (size_t) -1)
  52         memcpy (decimal, ".", 2);
  53       else
  54         decimal[n] = '\0';
  55
  56       memset (&state, '\0', sizeof (state));
  57
  58       n = __wcrtomb (thousands, wthousands, &state);
  59       if (n == (size_t) -1)
  60         memcpy (thousands, ",", 2);
  61       else
  62         thousands[n] = '\0';
  63     }
  64 #endif
  65
  66   /* Copy existing string so that nothing gets overwritten.  */
  67   CHAR_T *src;
  68   struct scratch_buffer buffer;
  69   scratch_buffer_init (&buffer);
  70   if (!scratch_buffer_set_array_size (&buffer, rear_ptr - w, sizeof (CHAR_T)))
  71     /* If we cannot allocate the memory don't rewrite the string.
  72        It is better than nothing.  */
  73     return w;
  74   src = buffer.data;
  75
  76   CHAR_T *s = (CHAR_T *) __mempcpy (src, w,
  77                                     (rear_ptr - w) * sizeof (CHAR_T));
  78
  79   w = end;
  80
  81   /* Process all characters in the string.  */
  82   while (--s >= src)
  83     {
  84       if (*s >= '0' && *s <= '9')
  85         {
  86           if (sizeof (CHAR_T) == 1)
  87             w = (CHAR_T *) outdigit_value ((char *) w, *s - '0');
  88           else
  89             *--w = (CHAR_T) outdigitwc_value (*s - '0');
  90         }
  91       else if (__builtin_expect (map == NULL, 1) || (*s != '.' && *s != ','))
  92         *--w = *s;
  93       else
  94         {
  95           if (sizeof (CHAR_T) == 1)
  96             {
  97               const char *outpunct = *s == '.' ? decimal : thousands;
  98               size_t dlen = strlen (outpunct);
  99
 100               w -= dlen;
 101               while (dlen-- > 0)
 102                 w[dlen] = outpunct[dlen];
 103             }
 104           else
 105             *--w = *s == '.' ? (CHAR_T) wdecimal : (CHAR_T) wthousands;
 106         }
 107     }
 108
 109   scratch_buffer_free (&buffer);
 110   return w;
 111 }