Subversion Repositories openrisc_2011-10-31

/*

FUNCTION

        <<wcstod>>, <<wcstof>>---wide char string to double or float

INDEX

        wcstod

INDEX

        _wcstod_r

INDEX

        wcstof

INDEX

        _wcstof_r

ANSI_SYNOPSIS

        #include <stdlib.h>

        double wcstod(const wchar_t *<[str]>, wchar_t **<[tail]>);

        float wcstof(const wchar_t *<[str]>, wchar_t **<[tail]>);

        double _wcstod_r(void *<[reent]>,

                         const wchar_t *<[str]>, wchar_t **<[tail]>);

        float _wcstof_r(void *<[reent]>,

                         const wchar_t *<[str]>, wchar_t **<[tail]>);

TRAD_SYNOPSIS

        #include <stdlib.h>

        double wcstod(<[str]>,<[tail]>)

        wchar_t *<[str]>;

        wchar_t **<[tail]>;

        float wcstof(<[str]>,<[tail]>)

        wchar_t *<[str]>;

        wchar_t **<[tail]>;

        double _wcstod_r(<[reent]>,<[str]>,<[tail]>)

        wchar_t *<[reent]>;

        wchar_t *<[str]>;

        wchar_t **<[tail]>;

        float _wcstof_r(<[reent]>,<[str]>,<[tail]>)

        wchar_t *<[reent]>;

        wchar_t *<[str]>;

        wchar_t **<[tail]>;

DESCRIPTION

        The function <<wcstod>> parses the wide character string <[str]>,

        producing a substring which can be converted to a double

        value.  The substring converted is the longest initial

        subsequence of <[str]>, beginning with the first

        non-whitespace character, that has one of these formats:

        .[+|-]<[digits]>[.[<[digits]>]][(e|E)[+|-]<[digits]>]

        .[+|-].<[digits]>[(e|E)[+|-]<[digits]>]

        .[+|-](i|I)(n|N)(f|F)[(i|I)(n|N)(i|I)(t|T)(y|Y)]

        .[+|-](n|N)(a|A)(n|N)[<(>[<[hexdigits]>]<)>]

        .[+|-]0(x|X)<[hexdigits]>[.[<[hexdigits]>]][(p|P)[+|-]<[digits]>]

        .[+|-]0(x|X).<[hexdigits]>[(p|P)[+|-]<[digits]>]

        The substring contains no characters if <[str]> is empty, consists

        entirely of whitespace, or if the first non-whitespace

        character is something other than <<+>>, <<->>, <<.>>, or a

        digit, and cannot be parsed as infinity or NaN. If the platform

        does not support NaN, then NaN is treated as an empty substring.

        If the substring is empty, no conversion is done, and

        the value of <[str]> is stored in <<*<[tail]>>>.  Otherwise,

        the substring is converted, and a pointer to the final string

        (which will contain at least the terminating null character of

        <[str]>) is stored in <<*<[tail]>>>.  If you want no

        assignment to <<*<[tail]>>>, pass a null pointer as <[tail]>.

        <<wcstof>> is identical to <<wcstod>> except for its return type.

        This implementation returns the nearest machine number to the

        input decimal string.  Ties are broken by using the IEEE

        round-even rule.  However, <<wcstof>> is currently subject to

        double rounding errors.

        The alternate functions <<_wcstod_r>> and <<_wcstof_r>> are

        reentrant versions of <<wcstod>> and <<wcstof>>, respectively.

        The extra argument <[reent]> is a pointer to a reentrancy structure.

RETURNS

        Return the converted substring value, if any.  If

        no conversion could be performed, 0 is returned.  If the

        correct value is out of the range of representable values,

        plus or minus <<HUGE_VAL>> is returned, and <<ERANGE>> is

        stored in errno. If the correct value would cause underflow, 0

        is returned and <<ERANGE>> is stored in errno.

Supporting OS subroutines required: <<close>>, <<fstat>>, <<isatty>>,

<<lseek>>, <<read>>, <<sbrk>>, <<write>>.

*/

/*-

 * Copyright (c) 2002 Tim J. Robbins

 * All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 * 1. Redistributions of source code must retain the above copyright

 *    notice, this list of conditions and the following disclaimer.

 * 2. Redistributions in binary form must reproduce the above copyright

 *    notice, this list of conditions and the following disclaimer in the

 *    documentation and/or other materials provided with the distribution.

 *

 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND

 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE

 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL

 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS

 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)

 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT

 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY

 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF

 * SUCH DAMAGE.

 */

#include <_ansi.h>

#include <errno.h>

#include <stdlib.h>

#include <string.h>

#include <wchar.h>

#include <wctype.h>

#include <locale.h>

#include <math.h>

double

_DEFUN (_wcstod_r, (ptr, nptr, endptr),

        struct _reent *ptr _AND

        _CONST wchar_t *nptr _AND

        wchar_t **endptr)

{

        static const mbstate_t initial;

        mbstate_t mbs;

        double val;

        char *buf, *end;

        const wchar_t *wcp;

        size_t len;

        while (iswspace(*nptr))

                nptr++;

        /*

         * Convert the supplied numeric wide char. string to multibyte.

         *

         * We could attempt to find the end of the numeric portion of the

         * wide char. string to avoid converting unneeded characters but

         * choose not to bother; optimising the uncommon case where

         * the input string contains a lot of text after the number

         * duplicates a lot of strtod()'s functionality and slows down the

         * most common cases.

         */

        wcp = nptr;

        mbs = initial;

        if ((len = _wcsrtombs_r(ptr, NULL, &wcp, 0, &mbs)) == (size_t)-1) {

                if (endptr != NULL)

                        *endptr = (wchar_t *)nptr;

                return (0.0);

        }

        if ((buf = _malloc_r(ptr, len + 1)) == NULL)

                return (0.0);

        mbs = initial;

        _wcsrtombs_r(ptr, buf, &wcp, len + 1, &mbs);

        /* Let strtod() do most of the work for us. */

        val = _strtod_r(ptr, buf, &end);

        /*

         * We only know where the number ended in the _multibyte_

         * representation of the string. If the caller wants to know

         * where it ended, count multibyte characters to find the

         * corresponding position in the wide char string.

         */

        if (endptr != NULL) {

                /* The only valid multibyte char in a float converted by

                   strtod/wcstod is the radix char.  What we do here is,

                   figure out if the radix char was in the valid leading

                   float sequence in the incoming string.  If so, the

                   multibyte float string is strlen(radix char) - 1 bytes

                   longer than the incoming wide char string has characters.

                   To fix endptr, reposition end as if the radix char was

                   just one byte long.  The resulting difference (end - buf)

                   is then equivalent to the number of valid wide characters

                   in the input string. */

                len = strlen (_localeconv_r (ptr)->decimal_point);

                if (len > 1) {

                        char *d = strstr (buf,

                                          _localeconv_r (ptr)->decimal_point);

                        if (d && d < end)

                                end -= len - 1;

                }

                *endptr = (wchar_t *)nptr + (end - buf);

        }

        _free_r(ptr, buf);

        return (val);

}

float

_DEFUN (_wcstof_r, (ptr, nptr, endptr),

        struct _reent *ptr _AND

        _CONST wchar_t *nptr _AND

        wchar_t **endptr)

{

  double retval = _wcstod_r (ptr, nptr, endptr);

  if (isnan (retval))

    return nanf (NULL);

  return (float)retval;

}

#ifndef _REENT_ONLY

double

_DEFUN (wcstod, (nptr, endptr),

        _CONST wchar_t *nptr _AND wchar_t **endptr)

{

  return _wcstod_r (_REENT, nptr, endptr);

}

float

_DEFUN (wcstof, (nptr, endptr),

        _CONST wchar_t *nptr _AND

        wchar_t **endptr)

{

  double retval = _wcstod_r (_REENT, nptr, endptr);

  if (isnan (retval))

    return nanf (NULL);

  return (float)retval;

}

#endif