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-rw-r--r--missing/strtod.c271
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diff --git a/missing/strtod.c b/missing/strtod.c
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index ce1c0f6d44..0000000000
--- a/missing/strtod.c
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@@ -1,271 +0,0 @@
-/*
- * strtod.c --
- *
- * Source code for the "strtod" library procedure.
- *
- * Copyright (c) 1988-1993 The Regents of the University of California.
- * Copyright (c) 1994 Sun Microsystems, Inc.
- *
- * Permission to use, copy, modify, and distribute this
- * software and its documentation for any purpose and without
- * fee is hereby granted, provided that the above copyright
- * notice appear in all copies. The University of California
- * makes no representations about the suitability of this
- * software for any purpose. It is provided "as is" without
- * express or implied warranty.
- *
- * RCS: @(#) $Id$
- */
-
-#include "ruby/config.h"
-#ifdef HAVE_STDLIB_H
-# include <stdlib.h>
-#endif
-#include <ctype.h>
-#include <errno.h>
-extern int errno;
-
-#ifndef __STDC__
-# ifdef __GNUC__
-# define const __const__
-# else
-# define const
-# endif
-#endif
-
-#ifndef TRUE
-#define TRUE 1
-#define FALSE 0
-#endif
-#ifndef NULL
-#define NULL 0
-#endif
-
-static int maxExponent = 511; /* Largest possible base 10 exponent. Any
- * exponent larger than this will already
- * produce underflow or overflow, so there's
- * no need to worry about additional digits.
- */
-static double powersOf10[] = { /* Table giving binary powers of 10. Entry */
- 10., /* is 10^2^i. Used to convert decimal */
- 100., /* exponents into floating-point numbers. */
- 1.0e4,
- 1.0e8,
- 1.0e16,
- 1.0e32,
- 1.0e64,
- 1.0e128,
- 1.0e256
-};
-
-/*
- *----------------------------------------------------------------------
- *
- * strtod --
- *
- * This procedure converts a floating-point number from an ASCII
- * decimal representation to internal double-precision format.
- *
- * Results:
- * The return value is the double-precision floating-point
- * representation of the characters in string. If endPtr isn't
- * NULL, then *endPtr is filled in with the address of the
- * next character after the last one that was part of the
- * floating-point number.
- *
- * Side effects:
- * None.
- *
- *----------------------------------------------------------------------
- */
-
-double
-strtod(string, endPtr)
- const char *string; /* A decimal ASCII floating-point number,
- * optionally preceded by white space.
- * Must have form "-I.FE-X", where I is the
- * integer part of the mantissa, F is the
- * fractional part of the mantissa, and X
- * is the exponent. Either of the signs
- * may be "+", "-", or omitted. Either I
- * or F may be omitted, or both. The decimal
- * point isn't necessary unless F is present.
- * The "E" may actually be an "e". E and X
- * may both be omitted (but not just one).
- */
- char **endPtr; /* If non-NULL, store terminating character's
- * address here. */
-{
- int sign, expSign = FALSE;
- double fraction, dblExp, *d;
- register const char *p;
- register int c;
- int exp = 0; /* Exponent read from "EX" field. */
- int fracExp = 0; /* Exponent that derives from the fractional
- * part. Under normal circumstatnces, it is
- * the negative of the number of digits in F.
- * However, if I is very long, the last digits
- * of I get dropped (otherwise a long I with a
- * large negative exponent could cause an
- * unnecessary overflow on I alone). In this
- * case, fracExp is incremented one for each
- * dropped digit. */
- int mantSize; /* Number of digits in mantissa. */
- int decPt; /* Number of mantissa digits BEFORE decimal
- * point. */
- const char *pExp; /* Temporarily holds location of exponent
- * in string. */
-
- /*
- * Strip off leading blanks and check for a sign.
- */
-
- p = string;
- while (isspace(*p)) {
- p += 1;
- }
- if (*p == '-') {
- sign = TRUE;
- p += 1;
- } else {
- if (*p == '+') {
- p += 1;
- }
- sign = FALSE;
- }
-
- /*
- * Count the number of digits in the mantissa (including the decimal
- * point), and also locate the decimal point.
- */
-
- decPt = -1;
- for (mantSize = 0; ; mantSize += 1)
- {
- c = *p;
- if (!isdigit(c)) {
- if ((c != '.') || (decPt >= 0)) {
- break;
- }
- decPt = mantSize;
- }
- p += 1;
- }
-
- /*
- * Now suck up the digits in the mantissa. Use two integers to
- * collect 9 digits each (this is faster than using floating-point).
- * If the mantissa has more than 18 digits, ignore the extras, since
- * they can't affect the value anyway.
- */
-
- pExp = p;
- p -= mantSize;
- if (decPt < 0) {
- decPt = mantSize;
- } else {
- mantSize -= 1; /* One of the digits was the point. */
- }
- if (mantSize > 18) {
- fracExp = decPt - 18;
- mantSize = 18;
- } else {
- fracExp = decPt - mantSize;
- }
- if (mantSize == 0) {
- fraction = 0.0;
- p = string;
- goto done;
- } else {
- int frac1, frac2;
- frac1 = 0;
- for ( ; mantSize > 9; mantSize -= 1)
- {
- c = *p;
- p += 1;
- if (c == '.') {
- c = *p;
- p += 1;
- }
- frac1 = 10*frac1 + (c - '0');
- }
- frac2 = 0;
- for (; mantSize > 0; mantSize -= 1)
- {
- c = *p;
- p += 1;
- if (c == '.') {
- c = *p;
- p += 1;
- }
- frac2 = 10*frac2 + (c - '0');
- }
- fraction = (1.0e9 * frac1) + frac2;
- }
-
- /*
- * Skim off the exponent.
- */
-
- p = pExp;
- if ((*p == 'E') || (*p == 'e')) {
- p += 1;
- if (*p == '-') {
- expSign = TRUE;
- p += 1;
- } else {
- if (*p == '+') {
- p += 1;
- }
- expSign = FALSE;
- }
- while (isdigit(*p)) {
- exp = exp * 10 + (*p - '0');
- p += 1;
- }
- }
- if (expSign) {
- exp = fracExp - exp;
- } else {
- exp = fracExp + exp;
- }
-
- /*
- * Generate a floating-point number that represents the exponent.
- * Do this by processing the exponent one bit at a time to combine
- * many powers of 2 of 10. Then combine the exponent with the
- * fraction.
- */
-
- if (exp < 0) {
- expSign = TRUE;
- exp = -exp;
- } else {
- expSign = FALSE;
- }
- if (exp > maxExponent) {
- exp = maxExponent;
- errno = ERANGE;
- }
- dblExp = 1.0;
- for (d = powersOf10; exp != 0; exp >>= 1, d += 1) {
- if (exp & 01) {
- dblExp *= *d;
- }
- }
- if (expSign) {
- fraction /= dblExp;
- } else {
- fraction *= dblExp;
- }
-
-done:
- if (endPtr != NULL) {
- *endPtr = (char *) p;
- }
-
- if (sign) {
- return -fraction;
- }
- return fraction;
-}
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