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/* mpfr_out_str -- output a floating-point number to a stream

Copyright 1999, 2001, 2002, 2004 Free Software Foundation, Inc.

This file is part of the MPFR Library.

The MPFR Library is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or (at your
option) any later version.

The MPFR Library is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
License for more details.

You should have received a copy of the GNU Lesser General Public License
along with the MPFR Library; see the file COPYING.LIB.  If not, write to
the Free Software Foundation, Inc., 51 Franklin Place, Fifth Floor, Boston,
MA 02110-1301, USA. */

#include <stdio.h>
#include <string.h>
#include <limits.h>
#include <locale.h>

#include "mpfr-impl.h"

size_t
mpfr_out_str (FILE *stream, int base, size_t n_digits, mpfr_srcptr op,
              mp_rnd_t rnd_mode)
{
  char *s, *s0;
  size_t l;
  mp_exp_t e;

  /* when stream=NULL, output to stdout */
  if (stream == NULL)
    stream = stdout;

  if (MPFR_IS_NAN(op))
    {
      fprintf (stream, "@NaN@");
      return 3;
    }

  if (MPFR_IS_INF(op))
    {
      if (MPFR_SIGN(op) > 0)
        {
          fprintf (stream, "@Inf@");
          return 3;
        }
      else
        {
          fprintf (stream, "-@Inf@");
          return 4;
        }
    }

  if (MPFR_IS_ZERO(op))
    {
      if (MPFR_SIGN(op) > 0)
        {
          fprintf(stream, "0");
          return 1;
        }
      else
        {
          fprintf(stream, "-0");
          return 2;
        }
    }

  s = mpfr_get_str (NULL, &e, base, n_digits, op, rnd_mode);

  s0 = s;
  /* for op=3.1416 we have s = "31416" and e = 1 */

  l = strlen (s) + 1; /* size of allocated block returned by mpfr_get_str
                         - may be incorrect, as only an upper bound? */
  if (*s == '-')
    fputc (*s++, stream);

  /* outputs mantissa */
  fputc (*s++, stream); e--; /* leading digit */
  fputc (MPFR_DECIMAL_POINT, stream);
  fputs (s, stream);         /* rest of mantissa */
  (*__gmp_free_func) (s0, l);

  /* outputs exponent */
  if (e)
    {
      MPFR_ASSERTN(e >= LONG_MIN);
      MPFR_ASSERTN(e <= LONG_MAX);
      l += fprintf (stream, (base <= 10 ? "e%ld" : "@%ld"), (long) e);
    }

  return l;
}