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/* error-checking interface to strtod-like functions
Copyright (C) 1996, 1999, 2000, 2003, 2004 Free Software Foundation, Inc.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
This program 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 General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software Foundation,
Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
/* Written by Jim Meyering. */
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include "xstrtod.h"
#include <errno.h>
#include <limits.h>
#include <stdio.h>
/* Tell the compiler that non-default rounding modes are used. */
#if 199901 <= __STDC_VERSION__
#pragma STDC FENV_ACCESS ON
#endif
/* An interface to strtod that encapsulates all the error checking
one should usually perform. Like strtod, but upon successful
conversion put the result in *RESULT and return true. Return
false and don't modify *RESULT upon any failure. CONVERT
specifies the conversion function, e.g., strtod itself. */
bool
xstrtod (char const *str, char const **ptr, double *result,
double (*convert) (char const *, char **))
{
double val;
char *terminator;
bool ok = true;
errno = 0;
val = convert (str, &terminator);
/* Having a non-zero terminator is an error only when PTR is NULL. */
if (terminator == str || (ptr == NULL && *terminator != '\0'))
ok = false;
else
{
/* Allow underflow (in which case strtod returns zero),
but flag overflow as an error. */
if (val != 0.0 && errno == ERANGE)
ok = false;
}
if (ptr != NULL)
*ptr = terminator;
*result = val;
return ok;
}
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