1/* mpf_out_str (stream, base, n_digits, op) -- Print N_DIGITS digits from
2   the float OP to STREAM in base BASE.  Return the number of characters
3   written, or 0 if an error occurred.
4
5Copyright 1996, 1997, 2001, 2002, 2005 Free Software Foundation, Inc.
6
7This file is part of the GNU MP Library.
8
9The GNU MP Library is free software; you can redistribute it and/or modify
10it under the terms of the GNU Lesser General Public License as published by
11the Free Software Foundation; either version 3 of the License, or (at your
12option) any later version.
13
14The GNU MP Library is distributed in the hope that it will be useful, but
15WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
16or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
17License for more details.
18
19You should have received a copy of the GNU Lesser General Public License
20along with the GNU MP Library.  If not, see http://www.gnu.org/licenses/.  */
21
22#define _GNU_SOURCE    /* for DECIMAL_POINT in langinfo.h */
23
24#include "config.h"
25
26#include <stdio.h>
27#include <string.h>
28
29#if HAVE_LANGINFO_H
30#include <langinfo.h>  /* for nl_langinfo */
31#endif
32
33#if HAVE_LOCALE_H
34#include <locale.h>    /* for localeconv */
35#endif
36
37#include "gmp.h"
38#include "gmp-impl.h"
39
40
41size_t
42mpf_out_str (FILE *stream, int base, size_t n_digits, mpf_srcptr op)
43{
44  char *str;
45  mp_exp_t exp;
46  size_t written;
47  TMP_DECL;
48
49  TMP_MARK;
50
51  if (base == 0)
52    base = 10;
53  if (n_digits == 0)
54    MPF_SIGNIFICANT_DIGITS (n_digits, base, op->_mp_prec);
55
56  if (stream == 0)
57    stream = stdout;
58
59  /* Consider these changes:
60     * Don't allocate memory here for huge n_digits; pass NULL to mpf_get_str.
61     * Make mpf_get_str allocate extra space when passed NULL, to avoid
62       allocating two huge string buffers.
63     * Implement more/other allocation reductions tricks.  */
64
65  str = (char *) TMP_ALLOC (n_digits + 2); /* extra for minus sign and \0 */
66
67  mpf_get_str (str, &exp, base, n_digits, op);
68  n_digits = strlen (str);
69
70  written = 0;
71
72  /* Write sign */
73  if (str[0] == '-')
74    {
75      str++;
76      fputc ('-', stream);
77      written = 1;
78      n_digits--;
79    }
80
81  {
82    const char  *point = GMP_DECIMAL_POINT;
83    size_t      pointlen = strlen (point);
84    putc ('0', stream);
85    fwrite (point, 1, pointlen, stream);
86    written += pointlen + 1;
87  }
88
89  /* Write mantissa */
90  {
91    size_t fwret;
92    fwret = fwrite (str, 1, n_digits, stream);
93    written += fwret;
94  }
95
96  /* Write exponent */
97  {
98    int fpret;
99    fpret = fprintf (stream, (base <= 10 ? "e%ld" : "@%ld"), exp);
100    written += fpret;
101  }
102
103  TMP_FREE;
104  return ferror (stream) ? 0 : written;
105}
106