diff options
Diffstat (limited to 'lib/strtod.c')
| -rw-r--r-- | lib/strtod.c | 189 |
1 files changed, 0 insertions, 189 deletions
diff --git a/lib/strtod.c b/lib/strtod.c deleted file mode 100644 index 7b48754e..00000000 --- a/lib/strtod.c +++ /dev/null @@ -1,189 +0,0 @@ -/* Copyright (C) 1991, 1992, 1997, 1999, 2003 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. */ - -#ifdef HAVE_CONFIG_H -# include <config.h> -#endif - -#include <errno.h> -#ifndef errno -extern int errno; -#endif - -#include <ctype.h> - -#if defined (STDC_HEADERS) || (!defined (isascii) && !defined (HAVE_ISASCII)) -# define IN_CTYPE_DOMAIN(c) 1 -#else -# define IN_CTYPE_DOMAIN(c) isascii(c) -#endif - -#define ISSPACE(c) (IN_CTYPE_DOMAIN (c) && isspace (c)) -#define ISDIGIT(c) (IN_CTYPE_DOMAIN (c) && isdigit (c)) -#define TOLOWER(c) (IN_CTYPE_DOMAIN (c) ? tolower(c) : (c)) - -#include <math.h> - -#include <float.h> -#include <stdlib.h> -#include <string.h> - -/* Convert NPTR to a double. If ENDPTR is not NULL, a pointer to the - character after the last one used in the number is put in *ENDPTR. */ -double -strtod (const char *nptr, char **endptr) -{ - register const char *s; - short int sign; - - /* The number so far. */ - double num; - - int got_dot; /* Found a decimal point. */ - int got_digit; /* Seen any digits. */ - - /* The exponent of the number. */ - long int exponent; - - if (nptr == NULL) - { - errno = EINVAL; - goto noconv; - } - - s = nptr; - - /* Eat whitespace. */ - while (ISSPACE (*s)) - ++s; - - /* Get the sign. */ - sign = *s == '-' ? -1 : 1; - if (*s == '-' || *s == '+') - ++s; - - num = 0.0; - got_dot = 0; - got_digit = 0; - exponent = 0; - for (;; ++s) - { - if (ISDIGIT (*s)) - { - got_digit = 1; - - /* Make sure that multiplication by 10 will not overflow. */ - if (num > DBL_MAX * 0.1) - /* The value of the digit doesn't matter, since we have already - gotten as many digits as can be represented in a `double'. - This doesn't necessarily mean the result will overflow. - The exponent may reduce it to within range. - - We just need to record that there was another - digit so that we can multiply by 10 later. */ - ++exponent; - else - num = (num * 10.0) + (*s - '0'); - - /* Keep track of the number of digits after the decimal point. - If we just divided by 10 here, we would lose precision. */ - if (got_dot) - --exponent; - } - else if (!got_dot && *s == '.') - /* Record that we have found the decimal point. */ - got_dot = 1; - else - /* Any other character terminates the number. */ - break; - } - - if (!got_digit) - goto noconv; - - if (TOLOWER (*s) == 'e') - { - /* Get the exponent specified after the `e' or `E'. */ - int save = errno; - char *end; - long int exp; - - errno = 0; - ++s; - exp = strtol (s, &end, 10); - if (errno == ERANGE) - { - /* The exponent overflowed a `long int'. It is probably a safe - assumption that an exponent that cannot be represented by - a `long int' exceeds the limits of a `double'. */ - if (endptr != NULL) - *endptr = end; - if (exp < 0) - goto underflow; - else - goto overflow; - } - else if (end == s) - /* There was no exponent. Reset END to point to - the 'e' or 'E', so *ENDPTR will be set there. */ - end = (char *) s - 1; - errno = save; - s = end; - exponent += exp; - } - - if (endptr != NULL) - *endptr = (char *) s; - - if (num == 0.0) - return 0.0; - - /* Multiply NUM by 10 to the EXPONENT power, - checking for overflow and underflow. */ - - if (exponent < 0) - { - if (num < DBL_MIN * pow (10.0, (double) -exponent)) - goto underflow; - } - else if (exponent > 0) - { - if (num > DBL_MAX * pow (10.0, (double) -exponent)) - goto overflow; - } - - num *= pow (10.0, (double) exponent); - - return num * sign; - -overflow: - /* Return an overflow error. */ - errno = ERANGE; - return HUGE_VAL * sign; - -underflow: - /* Return an underflow error. */ - if (endptr != NULL) - *endptr = (char *) nptr; - errno = ERANGE; - return 0.0; - -noconv: - /* There was no number. */ - if (endptr != NULL) - *endptr = (char *) nptr; - return 0.0; -} |