libquadmath/printf/_i18n_number.h

   1 /* Copyright (C) 2000, 2004, 2008 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, write to the Free
  17    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  18    02111-1307 USA.  */
  19
  20 /* Look up the value of the next multibyte character and return its numerical
  21    value if it is one of the digits known in the locale.  If *DECIDED is
  22    -1 this means it is not yet decided which form it is and we have to
  23    search through all available digits.  Otherwise we know which script
  24    the digits are from.  */
  25 static inline char *
  26 outdigit_value (char *s, int n)
  27 {
  28   const char *outdigit;
  29   size_t dlen;
  30
  31   assert (0 <= n && n <= 9);
  32   outdigit = nl_langinfo (_NL_CTYPE_OUTDIGIT0_MB + n);
  33   dlen = strlen (outdigit);
  34
  35   s -= dlen;
  36   while (dlen-- > 0)
  37     s[dlen] = outdigit[dlen];
  38
  39   return s;
  40 }
  41
  42 /* Look up the value of the next multibyte character and return its numerical
  43    value if it is one of the digits known in the locale.  If *DECIDED is
  44    -1 this means it is not yet decided which form it is and we have to
  45    search through all available digits.  Otherwise we know which script
  46    the digits are from.  */
  47 static inline wchar_t
  48 outdigitwc_value (int n)
  49 {
  50   assert (0 <= n && n <= 9);
  51
  52   return nl_langinfo_wc (_NL_CTYPE_OUTDIGIT0_WC + n);
  53 }
  54
  55 static char *
  56 _i18n_number_rewrite (char *w, char *rear_ptr, char *end)
  57 {
  58   char decimal[MB_LEN_MAX + 1];
  59   char thousands[MB_LEN_MAX + 1];
  60
  61   /* "to_outpunct" is a map from ASCII decimal point and thousands-sep
  62      to their equivalent in locale. This is defined for locales which
  63      use extra decimal point and thousands-sep.  */
  64   wctrans_t map = wctrans ("to_outpunct");
  65   wint_t wdecimal = towctrans (L_('.'), map);
  66   wint_t wthousands = towctrans (L_(','), map);
  67
  68   if (__builtin_expect (map != NULL, 0))
  69     {
  70       mbstate_t state;
  71       memset (&state, '\0', sizeof (state));
  72
  73       size_t n = wcrtomb (decimal, wdecimal, &state);
  74       if (n == (size_t) -1)
  75         memcpy (decimal, ".", 2);
  76       else
  77         decimal[n] = '\0';
  78
  79       memset (&state, '\0', sizeof (state));
  80
  81       n = wcrtomb (thousands, wthousands, &state);
  82       if (n == (size_t) -1)
  83         memcpy (thousands, ",", 2);
  84       else
  85         thousands[n] = '\0';
  86     }
  87
  88   /* Copy existing string so that nothing gets overwritten.  */
  89   char *src;
  90   int use_alloca = (rear_ptr - w) < 4096;
  91   if (__builtin_expect (use_alloca, 1))
  92     src = (char *) alloca (rear_ptr - w);
  93   else
  94     {
  95       src = (char *) malloc (rear_ptr - w);
  96       if (src == NULL)
  97         /* If we cannot allocate the memory don't rewrite the string.
  98            It is better than nothing.  */
  99         return w;
 100     }
 101
 102   memcpy (src, w, rear_ptr - w);
 103   char *s = src + (rear_ptr - w);
 104
 105   w = end;
 106
 107   /* Process all characters in the string.  */
 108   while (--s >= src)
 109     {
 110       if (*s >= '0' && *s <= '9')
 111         {
 112           if (sizeof (char) == 1)
 113             w = (char *) outdigit_value ((char *) w, *s - '0');
 114           else
 115             *--w = (char) outdigitwc_value (*s - '0');
 116         }
 117       else if (__builtin_expect (map == NULL, 1) || (*s != '.' && *s != ','))
 118         *--w = *s;
 119       else
 120         {
 121           if (sizeof (char) == 1)
 122             {
 123               const char *outpunct = *s == '.' ? decimal : thousands;
 124               size_t dlen = strlen (outpunct);
 125
 126               w -= dlen;
 127               while (dlen-- > 0)
 128                 w[dlen] = outpunct[dlen];
 129             }
 130           else
 131             *--w = *s == '.' ? (char) wdecimal : (char) wthousands;
 132         }
 133     }
 134
 135   if (! use_alloca)
 136     free (src);
 137
 138   return w;
 139 }