stdio-common/printf_size.c

   1 /* Print size value using units for orders of magnitude.
   2    Copyright (C) 1997-2002, 2004, 2006 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4    Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
   5    Based on a proposal by Larry McVoy <lm@sgi.com>.
   6
   7    The GNU C Library is free software; you can redistribute it and/or
   8    modify it under the terms of the GNU Lesser General Public
   9    License as published by the Free Software Foundation; either
  10    version 2.1 of the License, or (at your option) any later version.
  11
  12    The GNU C Library is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15    Lesser General Public License for more details.
  16
  17    You should have received a copy of the GNU Lesser General Public
  18    License along with the GNU C Library; if not, write to the Free
  19    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  20    02111-1307 USA.  */
  21
  22 #include <ctype.h>
  23 #include <ieee754.h>
  24 #include <math.h>
  25 #include <printf.h>
  26 #include <libioP.h>
  27
  28
  29 /* This defines make it possible to use the same code for GNU C library and
  30    the GNU I/O library.  */
  31 #define PUT(f, s, n) _IO_sputn (f, s, n)
  32 #define PAD(f, c, n) (wide ? _IO_wpadn (f, c, n) : INTUSE(_IO_padn) (f, c, n))
  33 /* We use this file GNU C library and GNU I/O library.  So make
  34    names equal.  */
  35 #undef putc
  36 #define putc(c, f) (wide \
  37                     ? (int)_IO_putwc_unlocked (c, f) : _IO_putc_unlocked (c, f))
  38 #define size_t  _IO_size_t
  39 #define FILE    _IO_FILE
  40 \f
  41 /* Macros for doing the actual output.  */
  42
  43 #define outchar(ch)                                                           \
  44   do                                                                          \
  45     {                                                                         \
  46       register const int outc = (ch);                                         \
  47       if (putc (outc, fp) == EOF)                                             \
  48         return -1;                                                            \
  49       ++done;                                                                 \
  50     } while (0)
  51
  52 #define PRINT(ptr, wptr, len)                                                 \
  53   do                                                                          \
  54     {                                                                         \
  55       register size_t outlen = (len);                                         \
  56       if (len > 20)                                                           \
  57         {                                                                     \
  58           if (PUT (fp, wide ? (const char *) wptr : ptr, outlen) != outlen)   \
  59             return -1;                                                        \
  60           ptr += outlen;                                                      \
  61           done += outlen;                                                     \
  62         }                                                                     \
  63       else                                                                    \
  64         {                                                                     \
  65           if (wide)                                                           \
  66             while (outlen-- > 0)                                              \
  67               outchar (*wptr++);                                              \
  68           else                                                                \
  69             while (outlen-- > 0)                                              \
  70               outchar (*ptr++);                                               \
  71         }                                                                     \
  72     } while (0)
  73
  74 #define PADN(ch, len)                                                         \
  75   do                                                                          \
  76     {                                                                         \
  77       if (PAD (fp, ch, len) != len)                                           \
  78         return -1;                                                            \
  79       done += len;                                                            \
  80     }                                                                         \
  81   while (0)
  82 \f
  83 /* Prototype for helper functions.  */
  84 extern int __printf_fp (FILE *fp, const struct printf_info *info,
  85                         const void *const *args);
  86
  87 \f
  88 int
  89 __printf_size (FILE *fp, const struct printf_info *info,
  90                const void *const *args)
  91 {
  92   /* Units for the both formats.  */
  93 #define BINARY_UNITS    " kmgtpezy"
  94 #define DECIMAL_UNITS   " KMGTPEZY"
  95   static const char units[2][sizeof (BINARY_UNITS)] =
  96   {
  97     BINARY_UNITS,       /* For binary format.  */
  98     DECIMAL_UNITS       /* For decimal format.  */
  99   };
 100   const char *tag = units[isupper (info->spec) != 0];
 101   int divisor = isupper (info->spec) ? 1000 : 1024;
 102
 103   /* The floating-point value to output.  */
 104   union
 105     {
 106       union ieee754_double dbl;
 107       union ieee854_long_double ldbl;
 108     }
 109   fpnum;
 110   const void *ptr = &fpnum;
 111
 112   int negative = 0;
 113
 114   /* "NaN" or "Inf" for the special cases.  */
 115   const char *special = NULL;
 116   const wchar_t *wspecial = NULL;
 117
 118   struct printf_info fp_info;
 119   int done = 0;
 120   int wide = info->wide;
 121
 122
 123   /* Fetch the argument value.  */
 124 #ifndef __NO_LONG_DOUBLE_MATH
 125   if (info->is_long_double && sizeof (long double) > sizeof (double))
 126     {
 127       fpnum.ldbl.d = *(const long double *) args[0];
 128
 129       /* Check for special values: not a number or infinity.  */
 130       if (__isnanl (fpnum.ldbl.d))
 131         {
 132           special = "nan";
 133           wspecial = L"nan";
 134           negative = 0;
 135         }
 136       else if (__isinfl (fpnum.ldbl.d))
 137         {
 138           special = "inf";
 139           wspecial = L"inf";
 140
 141           negative = fpnum.ldbl.d < 0;
 142         }
 143       else
 144         while (fpnum.ldbl.d >= divisor && tag[1] != '\0')
 145           {
 146             fpnum.ldbl.d /= divisor;
 147             ++tag;
 148           }
 149     }
 150   else
 151 #endif  /* no long double */
 152     {
 153       fpnum.dbl.d = *(const double *) args[0];
 154
 155       /* Check for special values: not a number or infinity.  */
 156       if (__isnan (fpnum.dbl.d))
 157         {
 158           special = "nan";
 159           wspecial = L"nan";
 160           negative = 0;
 161         }
 162       else if (__isinf (fpnum.dbl.d))
 163         {
 164           special = "inf";
 165           wspecial = L"inf";
 166
 167           negative = fpnum.dbl.d < 0;
 168         }
 169       else
 170         while (fpnum.dbl.d >= divisor && tag[1] != '\0')
 171           {
 172             fpnum.dbl.d /= divisor;
 173             ++tag;
 174           }
 175     }
 176
 177   if (special)
 178     {
 179       int width = info->prec > info->width ? info->prec : info->width;
 180
 181       if (negative || info->showsign || info->space)
 182         --width;
 183       width -= 3;
 184
 185       if (!info->left && width > 0)
 186         PADN (' ', width);
 187
 188       if (negative)
 189         outchar ('-');
 190       else if (info->showsign)
 191         outchar ('+');
 192       else if (info->space)
 193         outchar (' ');
 194
 195       PRINT (special, wspecial, 3);
 196
 197       if (info->left && width > 0)
 198         PADN (' ', width);
 199
 200       return done;
 201     }
 202
 203   /* Prepare to print the number.  We want to use `__printf_fp' so we
 204      have to prepare a `printf_info' structure.  */
 205   fp_info = *info;
 206   fp_info.spec = 'f';
 207   fp_info.prec = info->prec < 0 ? 3 : info->prec;
 208   fp_info.wide = wide;
 209
 210   if (fp_info.left && fp_info.pad == L' ')
 211     {
 212       /* We must do the padding ourself since the unit character must
 213          be placed before the padding spaces.  */
 214       fp_info.width = 0;
 215
 216       done = __printf_fp (fp, &fp_info, &ptr);
 217       if (done > 0)
 218         {
 219           outchar (*tag);
 220           if (info->width > done)
 221             PADN (' ', info->width - done);
 222         }
 223     }
 224   else
 225     {
 226       /* We can let __printf_fp do all the printing and just add our
 227          unit character afterwards.  */
 228       fp_info.width = info->width - 1;
 229
 230       done = __printf_fp (fp, &fp_info, &ptr);
 231       if (done > 0)
 232         outchar (*tag);
 233     }
 234
 235   return done;
 236 }
 237 ldbl_strong_alias (__printf_size, printf_size);
 238 \f
 239 /* This is the function used by `vfprintf' to determine number and
 240    type of the arguments.  */
 241 int
 242 printf_size_info (const struct printf_info *info, size_t n, int *argtypes)
 243 {
 244   /* We need only one double or long double argument.  */
 245   if (n >= 1)
 246     argtypes[0] = PA_DOUBLE | (info->is_long_double ? PA_FLAG_LONG_DOUBLE : 0);
 247
 248   return 1;
 249 }