stdio-common/_i18n_number.h

   1 /* Copyright (C) 2000-2016 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    <http://www.gnu.org/licenses/>.  */
  18
  19 #include <stdbool.h>
  20 #include <wchar.h>
  21 #include <wctype.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   bool use_alloca = __libc_use_alloca ((rear_ptr - w) * sizeof (CHAR_T));
  69   if (__builtin_expect (use_alloca, true))
  70     src = (CHAR_T *) alloca ((rear_ptr - w) * sizeof (CHAR_T));
  71   else
  72     {
  73       src = (CHAR_T *) malloc ((rear_ptr - w) * sizeof (CHAR_T));
  74       if (src == NULL)
  75         /* If we cannot allocate the memory don't rewrite the string.
  76            It is better than nothing.  */
  77         return w;
  78     }
  79
  80   CHAR_T *s = (CHAR_T *) __mempcpy (src, w,
  81                                     (rear_ptr - w) * sizeof (CHAR_T));
  82
  83   w = end;
  84
  85   /* Process all characters in the string.  */
  86   while (--s >= src)
  87     {
  88       if (*s >= '0' && *s <= '9')
  89         {
  90           if (sizeof (CHAR_T) == 1)
  91             w = (CHAR_T *) outdigit_value ((char *) w, *s - '0');
  92           else
  93             *--w = (CHAR_T) outdigitwc_value (*s - '0');
  94         }
  95       else if (__builtin_expect (map == NULL, 1) || (*s != '.' && *s != ','))
  96         *--w = *s;
  97       else
  98         {
  99           if (sizeof (CHAR_T) == 1)
 100             {
 101               const char *outpunct = *s == '.' ? decimal : thousands;
 102               size_t dlen = strlen (outpunct);
 103
 104               w -= dlen;
 105               while (dlen-- > 0)
 106                 w[dlen] = outpunct[dlen];
 107             }
 108           else
 109             *--w = *s == '.' ? (CHAR_T) wdecimal : (CHAR_T) wthousands;
 110         }
 111     }
 112
 113   if (! use_alloca)
 114     free (src);
 115
 116   return w;
 117 }