NetBSD/external/lgpl3/mpfr/dist/inp_str.c
mrg efee5258bc initial import of MPRF 3.0.1.
The MPFR library is a C library for multiple-precision floating-point
computations with exact rounding (also called correct rounding).  It is
based on the GMP multiple-precision library and should replace the MPF
class in further releases of GMP.

GCC >= 4.2 requires MPFR.
2011-06-20 05:53:01 +00:00

88 lines
2.5 KiB
C

/* mpf_inp_str(dest_float, stream, base) -- Input a number in base
BASE from stdio stream STREAM and store the result in DEST_FLOAT.
Copyright 1999, 2001, 2002, 2004, 2006, 2007, 2008, 2009, 2010, 2011 Free Software Foundation, Inc.
Contributed by the Arenaire and Cacao projects, INRIA.
(Copied from GMP, file mpf/inp_str.c)
This file is part of the GNU MPFR Library.
The GNU 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 3 of the License, or (at your
option) any later version.
The GNU 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 GNU MPFR Library; see the file COPYING.LESSER. If not, see
http://www.gnu.org/licenses/ or write to the Free Software Foundation, Inc.,
51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. */
#include <ctype.h>
#include "mpfr-impl.h"
size_t
mpfr_inp_str (mpfr_ptr rop, FILE *stream, int base, mpfr_rnd_t rnd_mode)
{
unsigned char *str;
size_t alloc_size, str_size;
int c;
int retval;
size_t nread;
if (stream == NULL)
stream = stdin;
alloc_size = 100;
str = (unsigned char *) (*__gmp_allocate_func) (alloc_size);
str_size = 0;
nread = 0;
/* Skip whitespace. */
do
{
c = getc (stream);
nread++;
}
while (isspace (c));
/* number of characters read is nread */
for (;;)
{
if (str_size >= alloc_size)
{
size_t old_alloc_size = alloc_size;
alloc_size = alloc_size * 3 / 2;
str = (unsigned char *)
(*__gmp_reallocate_func) (str, old_alloc_size, alloc_size);
}
if (c == EOF || isspace (c))
break;
str[str_size++] = (unsigned char) c;
c = getc (stream);
}
ungetc (c, stream);
/* number of characters read is nread + str_size - 1 */
/* we can exit the for loop only by the break instruction,
then necessarily str_size >= alloc_size was checked, so
now str_size < alloc_size */
str[str_size] = '\0';
retval = mpfr_set_str (rop, (char *) str, base, rnd_mode);
(*__gmp_free_func) (str, alloc_size);
if (retval == -1)
return 0; /* error */
return str_size + nread - 1;
}