gcc/libquadmath/quadmath_io.c
Tobias Burnus b5d4b580ad re PR fortran/46817 (Missing copyright header in libquadmath/*.[hc])
2011-01-17  Tobias Burnus  <burnus@net-b.de>

        PR fortran/46817
        * quadmath-imp.h: Refer to libquadmath not ot libiberty,
        bump copyright year and use /**/ instead of // comments.
        * quadmath.h: Ditto.
        * quadmath-weak.h: Ditto.
        * quadmath_io.c: Ditto.

From-SVN: r168892
2011-01-17 10:14:41 +01:00

111 lines
2.7 KiB
C

/* GCC Quad-Precision Math Library
Copyright (C) 2010, 2011 Free Software Foundation, Inc.
Written by Francois-Xavier Coudert <fxcoudert@gcc.gnu.org>
This file is part of the libquadmath library.
Libquadmath is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public
License as published by the Free Software Foundation; either
version 2 of the License, or (at your option) any later version.
Libquadmath 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
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with libquadmath; see the file COPYING.LIB. If
not, write to the Free Software Foundation, Inc., 51 Franklin Street - Fifth Floor,
Boston, MA 02110-1301, USA. */
#include "quadmath.h"
#include <stdio.h>
#include <string.h>
#define ABS(x) ((x) >= 0 ? (x) : -(x))
static void
format (char * res, const __float128 x, size_t n)
{
char buffer[1024];
char *p;
memset (buffer, 0, sizeof(buffer));
g_Qfmt (buffer, &x, n + 1, sizeof(buffer) - 3);
p = buffer + (*buffer == '-' ? 1 : 0);
/* The sign is the easiest part. */
res[0] = (signbitq (x) ? '-' : '+');
if (*p == '.')
{
/* We have a number smaller than 1, without exponent. */
int exp = 0;
char *c;
for (c = p+1; *c == '0'; c++)
exp++;
/* We move the string "exp" characters left. */
size_t l = strlen (p+1+exp);
memcpy (res + 2, p + 1 + exp, l);
memset (res + 2 + l, '0', n - l + 1);
sprintf (res + n + 3, "e-%02d", exp + 1);
res[1] = res[2];
res[2] = '.';
return;
}
/* Now, do we already have an exponent. */
char *c;
for (c = p; *c && *c != 'e'; c++)
;
if (*c)
{
int exp = strtol (c + 1, NULL, 10);
size_t l = c - p;
memcpy (res + 1, p, l);
if (l <= n + 1)
memset (res + 1 + l, '0', (int) n - l + 2);
sprintf (res + n + 3, "e%c%02d", exp >= 0 ? '+' : '-', ABS(exp));
return;
}
else
{
/* If we have no exponent, normalize and add the exponent. */
for (c = p; *c && *c != '.'; c++)
;
res[1] = *p;
res[2] = '.';
size_t l = c - p;
memcpy (res + 3, p + 1, l);
size_t l2 = strlen (c + 1);
memcpy (res + 2 + l, c + 1, l2);
memset (res + 2 + l + l2, '0', n - (l + l2) + 1);
sprintf (res + n + 3, "e+%02d", l - 1);
return;
}
}
void
quadmath_flt128tostr (char *s, size_t size, size_t n, __float128 x)
{
char buffer[1024];
memset (buffer, 0, sizeof(buffer));
format (buffer, x, n);
memcpy (s, buffer, size);
}