fconv.c

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/* @(#)fconv.c  1.45 10/11/06 Copyright 1985, 1995-2010 J. Schilling */
/*
 *  Convert floating point numbers to strings for format.c
 *  Should rather use the MT-safe routines [efg]convert()
 *
 *  Copyright (c) 1985, 1995-2010 J. Schilling
 */
/*
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * See the file CDDL.Schily.txt in this distribution for details.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file CDDL.Schily.txt from this distribution.
 */

#include <schily/mconfig.h> /* <- may define NO_FLOATINGPOINT */
#ifndef NO_FLOATINGPOINT

#ifndef __DO_LONG_DOUBLE__
#include <schily/stdlib.h>
#include <schily/standard.h>
#include <schily/string.h>
#include <schily/schily.h>
#include <schily/math.h>    /* The default place for isinf()/isnan() */
#include <schily/nlsdefs.h>

#if !defined(HAVE_STDLIB_H) || defined(HAVE_DTOA)
extern  char    *ecvt __PR((double, int, int *, int *));
extern  char    *fcvt __PR((double, int, int *, int *));
#endif

#if defined(HAVE_ISNAN) && defined(HAVE_ISINF)
/*
 * *BSD alike libc
 */
#define FOUND_ISNAN
#define FOUND_ISINF
#define FOUND_ISXX
#endif

#if defined(HAVE_C99_ISNAN) && defined(HAVE_C99_ISINF)
#ifndef FOUND_ISXX
#define FOUND_ISXX
#endif
#define FOUND_C99_ISNAN
#define FOUND_C99_ISINF
#define FOUND_C99_ISXX
#endif

#if defined(HAVE_FP_H) && !defined(FOUND_ISXX)
/*
 * WAS:
 * #if  defined(__osf__) || defined(_IBMR2) || defined(_AIX)
 */
/*
 * Moved before HAVE_IEEEFP_H for True64 due to a hint
 * from Bert De Knuydt <Bert.Deknuydt@esat.kuleuven.ac.be>
 *
 * True64 has both fp.h & ieeefp.h but the functions
 * isnand() & finite() seem to be erreneously not implemented
 * as a macro and the function lives in libm.
 * Let's hope that we will not get problems with the new order.
 */
#include <fp.h>
#if !defined(isnan) && defined(IS_NAN)
#define isnan   IS_NAN
#define FOUND_ISNAN
#endif
#if !defined(isinf) && defined(FINITE)
#define isinf   !FINITE
#define FOUND_ISINF
#endif
#if defined(FOUND_ISNAN) && defined(FOUND_ISINF)
#define FOUND_ISXX
#endif
#endif

#if defined(HAVE_IEEEFP_H) && !defined(FOUND_ISXX) && \
    !defined(FOUND_C99_ISXX)
/*
 * SVR4
 */
#include <ieeefp.h>
#ifdef  HAVE_ISNAND
#ifndef isnan
#define isnan   isnand
#define FOUND_ISNAN
#endif
#endif
#ifdef  HAVE_FINITE
#ifndef isinf
#define isinf   !finite
#define FOUND_ISINF
#endif
#endif
#if defined(FOUND_ISNAN) && defined(FOUND_ISINF)
#define FOUND_ISXX
#endif
#endif

/*
 * WAS:
 * #if  defined(__hpux) || defined(VMS) || defined(_SCO_DS) || defined(__QNX__)
 */
#ifdef  __nneded__
#if defined(__hpux) || defined(__QNX__) || defined(__DJGPP__)
#ifndef FOUND_C99_ISXX
#undef  isnan
#undef  isinf
#endif
#endif
#endif  /* __needed__ */

/*
 * As we no longer check for defined(isnan)/defined(isinf), the next block
 * should also handle the problems with DJGPP, HP-UX, QNX and VMS.
 */
#if !defined(FOUND_ISNAN) && !defined(HAVE_C99_ISNAN)
#undef  isnan
#define isnan(val)  (0)
#define NO_ISNAN
#endif
#if !defined(FOUND_ISINF) && !defined(HAVE_C99_ISINF)
#undef  isinf
#define isinf(val)  (0)
#define NO_ISINF
#endif

#if defined(NO_ISNAN) || defined(NO_ISINF)
#include <schily/float.h>   /* For values.h */
#if (_IEEE - 0) > 0     /* We know that there is IEEE FP */
/*
 * Note that older HP-UX versions have different #defines for MAXINT in
 * values.h and sys/param.h
 */
#include <schily/utypes.h>
#include <schily/btorder.h>

#ifdef  WORDS_BIGENDIAN
#define fpw_high(x) ((UInt32_t *)&x)[0]
#define fpw_low(x)  ((UInt32_t *)&x)[1]
#else
#define fpw_high(x) ((UInt32_t *)&x)[1]
#define fpw_low(x)  ((UInt32_t *)&x)[0]
#endif
#define FP_EXP      0x7FF00000
#define fp_exp(x)   (fpw_high(x) & FP_EXP)
#define fp_exc(x)   (fp_exp(x) == FP_EXP)

#ifdef  NO_ISNAN
#undef  isnan
#define isnan(val)  (fp_exc(val) && \
            (fpw_low(val) != 0 || (fpw_high(val) & 0xFFFFF) != 0))
#endif
#ifdef  NO_ISINF
#undef  isinf
#define isinf(val)  (fp_exc(val) && \
            fpw_low(val) == 0 && (fpw_high(val) & 0xFFFFF) == 0)
#endif
#endif  /* We know that there is IEEE FP */
#endif  /* defined(NO_ISNAN) || defined(NO_ISINF) */


#if !defined(HAVE_ECVT) || !defined(HAVE_FCVT) || !defined(HAVE_GCVT)

#ifdef  NO_USER_XCVT
    /*
     * We cannot define our own ecvt()/fcvt()/gcvt() so we need to use
     * local names instead.
     */
#ifndef HAVE_ECVT
#define ecvt    js_ecvt
#endif
#ifndef HAVE_FCVT
#define fcvt    js_fcvt
#endif
#ifndef HAVE_GCVT
#define gcvt    js_gcvt
#endif
#endif

#include "cvt.c"
#endif

static  char    _js_nan[] = "(NaN)";
static  char    _js_inf[] = "(Infinity)";

static  int _ferr __PR((char *, double));
#endif  /* __DO_LONG_DOUBLE__ */

#ifdef  __DO_LONG_DOUBLE__
#undef  MDOUBLE
#define MDOUBLE long double
#else
#undef  MDOUBLE
#define MDOUBLE double
#endif

#ifdef  abs
#undef  abs
#endif
#define abs(i)  ((i) < 0 ? -(i) : (i))

EXPORT int
ftoes(s, val, fieldwidth, ndigits)
    register    char    *s;
            MDOUBLE val;
    register    int fieldwidth;
    register    int ndigits;
{
    register    char    *b;
    register    char    *rs;
    register    int len;
    register    int rdecpt;
            int     decpt;
            int sign;

#ifndef __DO_LONG_DOUBLE__
    if ((len = _ferr(s, val)) > 0)
        return (len);
#endif
    rs = s;
#ifdef  V7_FLOATSTYLE
    b = ecvt(val, ndigits, &decpt, &sign);
    rdecpt = decpt;
#else
    b = ecvt(val, ndigits+1, &decpt, &sign);
    rdecpt = decpt-1;
#endif
#ifdef  __DO_LONG_DOUBLE__
    len = *b;
    if (len < '0' || len > '9') {       /* Inf/NaN */
        strcpy(s, b);
        return (strlen(b));
    }
#endif
    len = ndigits + 6;          /* Punkt e +/- nnn */
    if (sign)
        len++;
    if (fieldwidth > len)
        while (fieldwidth-- > len)
            *rs++ = ' ';
    if (sign)
        *rs++ = '-';
#ifndef V7_FLOATSTYLE
    if (*b)
        *rs++ = *b++;
#endif
#if defined(HAVE_LOCALECONV) && defined(USE_LOCALE)
    *rs++ = *(localeconv()->decimal_point);
#else
    *rs++ = '.';
#endif
    while (*b && ndigits-- > 0)
        *rs++ = *b++;
    *rs++ = 'e';
    *rs++ = rdecpt >= 0 ? '+' : '-';
    rdecpt = abs(rdecpt);
#ifdef  __DO_LONG_DOUBLE__
    if (rdecpt >= 1000) {           /* Max-Exp is > 4000 */
        *rs++ = rdecpt / 1000 + '0';
        rdecpt %= 1000;
    }
#endif
#ifndef V7_FLOATSTYLE
    if (rdecpt >= 100)
#endif
    {
        *rs++ = rdecpt / 100 + '0';
        rdecpt %= 100;
    }
    *rs++ = rdecpt / 10 + '0';
    *rs++ = rdecpt % 10 + '0';
    *rs = '\0';
    return (rs - s);
}

/*
 * fcvt() from Cygwin32 is buggy.
 */
#if !defined(HAVE_FCVT) && defined(HAVE_ECVT)
#define USE_ECVT
#endif

EXPORT int
ftofs(s, val, fieldwidth, ndigits)
    register    char    *s;
            MDOUBLE val;
    register    int fieldwidth;
    register    int ndigits;
{
    register    char    *b;
    register    char    *rs;
    register    int len;
    register    int rdecpt;
            int     decpt;
            int sign;

#ifndef __DO_LONG_DOUBLE__
    if ((len = _ferr(s, val)) > 0)
        return (len);
#endif
    rs = s;
#ifdef  USE_ECVT
    /*
     * Needed on systems with broken fcvt() implementation
     * (e.g. Cygwin32)
     */
    b = ecvt(val, ndigits, &decpt, &sign);
    /*
     * The next call is needed to force higher precision.
     */
    if (decpt > 0)
        b = ecvt(val, ndigits+decpt, &decpt, &sign);
#else
    b = fcvt(val, ndigits, &decpt, &sign);
#endif
#ifdef  __DO_LONG_DOUBLE__
    len = *b;
    if (len < '0' || len > '9') {       /* Inf/NaN */
        strcpy(s, b);
        return (strlen(b));
    }
#endif
    rdecpt = decpt;
    len = rdecpt + ndigits + 1;
    if (rdecpt < 0)
        len -= rdecpt;
    if (sign)
        len++;
    if (fieldwidth > len)
        while (fieldwidth-- > len)
            *rs++ = ' ';
    if (sign)
        *rs++ = '-';
    if (rdecpt > 0) {
        len = rdecpt;
        while (*b && len-- > 0)
            *rs++ = *b++;
#ifdef  USE_ECVT
        while (len-- > 0)
            *rs++ = '0';
#endif
    }
#ifndef V7_FLOATSTYLE
    else {
        *rs++ = '0';
    }
#endif
#if defined(HAVE_LOCALECONV) && defined(USE_LOCALE)
    *rs++ = *(localeconv()->decimal_point);
#else
    *rs++ = '.';
#endif
    if (rdecpt < 0) {
        len = rdecpt;
        while (len++ < 0 && ndigits-- > 0)
            *rs++ = '0';
    }
    while (*b && ndigits-- > 0)
        *rs++ = *b++;
#ifdef  USE_ECVT
    while (ndigits-- > 0)
        *rs++ = '0';
#endif
    *rs = '\0';
    return (rs - s);
}

#ifndef __DO_LONG_DOUBLE__

#ifdef  HAVE_LONGDOUBLE
#ifdef  HAVE__LDECVT
#define qecvt(ld, n, dp, sp)    _ldecvt(*(long_double *)&ld, n, dp, sp)
#endif
#ifdef  HAVE__LDFCVT
#define qfcvt(ld, n, dp, sp)    _ldfcvt(*(long_double *)&ld, n, dp, sp)
#endif

#if (defined(HAVE_QECVT) || defined(HAVE__LDECVT)) && \
    (defined(HAVE_QFCVT) || defined(HAVE__LDFCVT))
#define __DO_LONG_DOUBLE__
#define ftoes   qftoes
#define ftofs   qftofs
#define ecvt    qecvt
#define fcvt    qfcvt
#include "fconv.c"
#undef  __DO_LONG_DOUBLE__
#endif
#endif  /* HAVE_LONGDOUBLE */

LOCAL int
_ferr(s, val)
    char    *s;
    double  val;
{
    if (isnan(val)) {
        strcpy(s, _js_nan);
        return (sizeof (_js_nan) - 1);
    }

    /*
     * Check first for NaN because finite() will return 1 on Nan too.
     */
    if (isinf(val)) {
        strcpy(s, _js_inf);
        return (sizeof (_js_inf) - 1);
    }
    return (0);
}
#endif  /* __DO_LONG_DOUBLE__ */
#endif  /* NO_FLOATINGPOINT */