/* Floating point output for `printf'.

   Copyright (C) 1995-2018 Free Software Foundation, Inc.

   This file is part of the GNU C Library.

   Written by Ulrich Drepper <drepper@gnu.ai.mit.edu>, 1995.

   The GNU C Library is free software; you can redistribute it and/or

   modify it under the terms of the GNU Lesser General Public

   License as published by the Free Software Foundation; either

   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library 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

   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public

   License along with the GNU C Library; if not, see

   <http://www.gnu.org/licenses/>.  */

/* The gmp headers need some configuration frobs.  */

#define HAVE_ALLOCA 1

#include <array_length.h>

#include <libioP.h>

#include <alloca.h>

#include <ctype.h>

#include <float.h>

#include <gmp-mparam.h>

#include <gmp.h>

#include <ieee754.h>

#include <stdlib/gmp-impl.h>

#include <stdlib/longlong.h>

#include <stdlib/fpioconst.h>

#include <locale/localeinfo.h>

#include <limits.h>

#include <math.h>

#include <printf.h>

#include <string.h>

#include <unistd.h>

#include <stdlib.h>

#include <wchar.h>

#include <stdbool.h>

#include <rounding-mode.h>

#ifdef COMPILE_WPRINTF

# define CHAR_T        wchar_t

#else

# define CHAR_T        char

#endif

#include "_i18n_number.h"

#ifndef NDEBUG

# define NDEBUG			/* Undefine this for debugging assertions.  */

#endif

#include <assert.h>

#define PUT(f, s, n) _IO_sputn (f, s, n)

#define PAD(f, c, n) (wide ? _IO_wpadn (f, c, n) : _IO_padn (f, c, n))

#undef putc

#define putc(c, f) (wide \

		    ? (int)_IO_putwc_unlocked (c, f) : _IO_putc_unlocked (c, f))

/* Macros for doing the actual output.  */

#define outchar(ch)							      \

  do									      \

    {									      \

      const int outc = (ch);						      \

      if (putc (outc, fp) == EOF)					      \

	{								      \

	  if (buffer_malloced)						      \

	    free (wbuffer);						      \

	  return -1;							      \

	}								      \

      ++done;								      \

    } while (0)

#define PRINT(ptr, wptr, len)						      \

  do									      \

    {									      \

      size_t outlen = (len);						      \

      if (len > 20)							      \

	{								      \

	  if (PUT (fp, wide ? (const char *) wptr : ptr, outlen) != outlen)   \

	    {								      \

	      if (buffer_malloced)					      \

		free (wbuffer);						      \

	      return -1;						      \

	    }								      \

	  ptr += outlen;						      \

	  done += outlen;						      \

	}								      \

      else								      \

	{								      \

	  if (wide)							      \

	    while (outlen-- > 0)					      \

	      outchar (*wptr++);					      \

	  else								      \

	    while (outlen-- > 0)					      \

	      outchar (*ptr++);						      \

	}								      \

    } while (0)

#define PADN(ch, len)							      \

  do									      \

    {									      \

      if (PAD (fp, ch, len) != len)					      \

	{								      \

	  if (buffer_malloced)						      \

	    free (wbuffer);						      \

	  return -1;							      \

	}								      \

      done += len;							      \

    }									      \

  while (0)

/* We use the GNU MP library to handle large numbers.

   An MP variable occupies a varying number of entries in its array.  We keep

   track of this number for efficiency reasons.  Otherwise we would always

   have to process the whole array.  */

#define MPN_VAR(name) mp_limb_t *name; mp_size_t name##size

#define MPN_ASSIGN(dst,src)						      \

  memcpy (dst, src, (dst##size = src##size) * sizeof (mp_limb_t))

#define MPN_GE(u,v) \

  (u##size > v##size || (u##size == v##size && __mpn_cmp (u, v, u##size) >= 0))

extern mp_size_t __mpn_extract_double (mp_ptr res_ptr, mp_size_t size,

				       int *expt, int *is_neg,

				       double value);

extern mp_size_t __mpn_extract_long_double (mp_ptr res_ptr, mp_size_t size,

					    int *expt, int *is_neg,

					    long double value);

static wchar_t *group_number (wchar_t *buf, wchar_t *bufend,

			      unsigned int intdig_no, const char *grouping,

			      wchar_t thousands_sep, int ngroups);

struct hack_digit_param

{

  /* Sign of the exponent.  */

  int expsign;

  /* The type of output format that will be used: 'e'/'E' or 'f'.  */

  int type;

  /* and the exponent.	*/

  int exponent;

  /* The fraction of the floting-point value in question  */

  MPN_VAR(frac);

  /* Scaling factor.  */

  MPN_VAR(scale);

  /* Temporary bignum value.  */

  MPN_VAR(tmp);

};

static wchar_t

hack_digit (struct hack_digit_param *p)

{

  mp_limb_t hi;

  if (p->expsign != 0 && p->type == 'f' && p->exponent-- > 0)

    hi = 0;

  else if (p->scalesize == 0)

    {

      hi = p->frac[p->fracsize - 1];

      p->frac[p->fracsize - 1] = __mpn_mul_1 (p->frac, p->frac,

	p->fracsize - 1, 10);

    }

  else

    {

      if (p->fracsize < p->scalesize)

	hi = 0;

      else

	{

	  hi = mpn_divmod (p->tmp, p->frac, p->fracsize,

	    p->scale, p->scalesize);

	  p->tmp[p->fracsize - p->scalesize] = hi;

	  hi = p->tmp[0];

	  p->fracsize = p->scalesize;

	  while (p->fracsize != 0 && p->frac[p->fracsize - 1] == 0)

	    --p->fracsize;

	  if (p->fracsize == 0)

	    {

	      /* We're not prepared for an mpn variable with zero

		 limbs.  */

	      p->fracsize = 1;

	      return L'0' + hi;

	    }

	}

      mp_limb_t _cy = __mpn_mul_1 (p->frac, p->frac, p->fracsize, 10);

      if (_cy != 0)

	p->frac[p->fracsize++] = _cy;

    }

  return L'0' + hi;

}

int

__printf_fp_l (FILE *fp, locale_t loc,

	       const struct printf_info *info,

	       const void *const *args)

{

  /* The floating-point value to output.  */

  union

    {

      double dbl;

      long double ldbl;

#if __HAVE_DISTINCT_FLOAT128

      _Float128 f128;

#endif

    }

  fpnum;

  /* Locale-dependent representation of decimal point.	*/

  const char *decimal;

  wchar_t decimalwc;

  /* Locale-dependent thousands separator and grouping specification.  */

  const char *thousands_sep = NULL;

  wchar_t thousands_sepwc = 0;

  const char *grouping;

  /* "NaN" or "Inf" for the special cases.  */

  const char *special = NULL;

  const wchar_t *wspecial = NULL;

  /* When _Float128 is enabled in the library and ABI-distinct from long

     double, we need mp_limbs enough for any of them.  */

#if __HAVE_DISTINCT_FLOAT128

# define GREATER_MANT_DIG FLT128_MANT_DIG

#else

# define GREATER_MANT_DIG LDBL_MANT_DIG

#endif

  /* We need just a few limbs for the input before shifting to the right

     position.	*/

  mp_limb_t fp_input[(GREATER_MANT_DIG + BITS_PER_MP_LIMB - 1)

		     / BITS_PER_MP_LIMB];

  /* We need to shift the contents of fp_input by this amount of bits.	*/

  int to_shift = 0;

  struct hack_digit_param p;

  /* Sign of float number.  */

  int is_neg = 0;

  /* Counter for number of written characters.	*/

  int done = 0;

  /* General helper (carry limb).  */

  mp_limb_t cy;

  /* Nonzero if this is output on a wide character stream.  */

  int wide = info->wide;

  /* Buffer in which we produce the output.  */

  wchar_t *wbuffer = NULL;

  /* Flag whether wbuffer is malloc'ed or not.  */

  int buffer_malloced = 0;

  p.expsign = 0;

  /* Figure out the decimal point character.  */

  if (info->extra == 0)

    {

      decimal = _nl_lookup (loc, LC_NUMERIC, DECIMAL_POINT);

      decimalwc = _nl_lookup_word

	(loc, LC_NUMERIC, _NL_NUMERIC_DECIMAL_POINT_WC);

    }

  else

    {

      decimal = _nl_lookup (loc, LC_MONETARY, MON_DECIMAL_POINT);

      if (*decimal == '\0')

	decimal = _nl_lookup (loc, LC_NUMERIC, DECIMAL_POINT);

      decimalwc = _nl_lookup_word (loc, LC_MONETARY,

				    _NL_MONETARY_DECIMAL_POINT_WC);

      if (decimalwc == L'\0')

	decimalwc = _nl_lookup_word (loc, LC_NUMERIC,

				      _NL_NUMERIC_DECIMAL_POINT_WC);

    }

  /* The decimal point character must not be zero.  */

  assert (*decimal != '\0');

  assert (decimalwc != L'\0');

  if (info->group)

    {

      if (info->extra == 0)

	grouping = _nl_lookup (loc, LC_NUMERIC, GROUPING);

      else

	grouping = _nl_lookup (loc, LC_MONETARY, MON_GROUPING);

      if (*grouping <= 0 || *grouping == CHAR_MAX)

	grouping = NULL;

      else

	{

	  /* Figure out the thousands separator character.  */

	  if (wide)

	    {

	      if (info->extra == 0)

		thousands_sepwc = _nl_lookup_word

		  (loc, LC_NUMERIC, _NL_NUMERIC_THOUSANDS_SEP_WC);

	      else

		thousands_sepwc =

		  _nl_lookup_word (loc, LC_MONETARY,

				    _NL_MONETARY_THOUSANDS_SEP_WC);

	    }

	  else

	    {

	      if (info->extra == 0)

		thousands_sep = _nl_lookup (loc, LC_NUMERIC, THOUSANDS_SEP);

	      else

		thousands_sep = _nl_lookup

		  (loc, LC_MONETARY, MON_THOUSANDS_SEP);

	    }

	  if ((wide && thousands_sepwc == L'\0')

	      || (! wide && *thousands_sep == '\0'))

	    grouping = NULL;

	  else if (thousands_sepwc == L'\0')

	    /* If we are printing multibyte characters and there is a

	       multibyte representation for the thousands separator,

	       we must ensure the wide character thousands separator

	       is available, even if it is fake.  */

	    thousands_sepwc = 0xfffffffe;

	}

    }

  else

    grouping = NULL;

#define PRINTF_FP_FETCH(FLOAT, VAR, SUFFIX, MANT_DIG)			\

  {									\

    (VAR) = *(const FLOAT *) args[0];					\

									\

    /* Check for special values: not a number or infinity.  */		\

    if (isnan (VAR))							\

      {									\

	is_neg = signbit (VAR);						\

	if (isupper (info->spec))					\

	  {								\

	    special = "NAN";						\

	    wspecial = L"NAN";						\

	  }								\

	else								\

	  {								\

	    special = "nan";						\

	    wspecial = L"nan";						\

	  }								\

      }									\

    else if (isinf (VAR))						\

      {									\

	is_neg = signbit (VAR);						\

	if (isupper (info->spec))					\

	  {								\

	    special = "INF";						\

	    wspecial = L"INF";						\

	  }								\

	else								\

	  {								\

	    special = "inf";						\

	    wspecial = L"inf";						\

	  }								\

      }									\

    else								\

      {									\

	p.fracsize = __mpn_extract_##SUFFIX				\

		     (fp_input, array_length (fp_input),		\

		      &p.exponent, &is_neg, VAR);			\

	to_shift = 1 + p.fracsize * BITS_PER_MP_LIMB - MANT_DIG;	\

      }									\

  }

  /* Fetch the argument value.	*/

#if __HAVE_DISTINCT_FLOAT128

  if (info->is_binary128)

    PRINTF_FP_FETCH (_Float128, fpnum.f128, float128, FLT128_MANT_DIG)

  else

#endif

#ifndef __NO_LONG_DOUBLE_MATH

  if (info->is_long_double && sizeof (long double) > sizeof (double))

    PRINTF_FP_FETCH (long double, fpnum.ldbl, long_double, LDBL_MANT_DIG)

  else

#endif

    PRINTF_FP_FETCH (double, fpnum.dbl, double, DBL_MANT_DIG)

#undef PRINTF_FP_FETCH

  if (special)

    {

      int width = info->width;

      if (is_neg || info->showsign || info->space)

	--width;

      width -= 3;

      if (!info->left && width > 0)

	PADN (' ', width);

      if (is_neg)

	outchar ('-');

      else if (info->showsign)

	outchar ('+');

      else if (info->space)

	outchar (' ');

      PRINT (special, wspecial, 3);

      if (info->left && width > 0)

	PADN (' ', width);

      return done;

    }

  /* We need three multiprecision variables.  Now that we have the p.exponent

     of the number we can allocate the needed memory.  It would be more

     efficient to use variables of the fixed maximum size but because this

     would be really big it could lead to memory problems.  */

  {

    mp_size_t bignum_size = ((abs (p.exponent) + BITS_PER_MP_LIMB - 1)

			     / BITS_PER_MP_LIMB

			     + (GREATER_MANT_DIG / BITS_PER_MP_LIMB > 2

				? 8 : 4))

			    * sizeof (mp_limb_t);

    p.frac = (mp_limb_t *) alloca (bignum_size);

    p.tmp = (mp_limb_t *) alloca (bignum_size);

    p.scale = (mp_limb_t *) alloca (bignum_size);

  }

  /* We now have to distinguish between numbers with positive and negative

     exponents because the method used for the one is not applicable/efficient

     for the other.  */

  p.scalesize = 0;

  if (p.exponent > 2)

    {

      /* |FP| >= 8.0.  */

      int scaleexpo = 0;

      int explog;

#if __HAVE_DISTINCT_FLOAT128

      if (info->is_binary128)

	explog = FLT128_MAX_10_EXP_LOG;

      else

	explog = LDBL_MAX_10_EXP_LOG;

#else

      explog = LDBL_MAX_10_EXP_LOG;

#endif

      int exp10 = 0;

      const struct mp_power *powers = &_fpioconst_pow10[explog + 1];

      int cnt_h, cnt_l, i;

      if ((p.exponent + to_shift) % BITS_PER_MP_LIMB == 0)

	{

	  MPN_COPY_DECR (p.frac + (p.exponent + to_shift) / BITS_PER_MP_LIMB,

			 fp_input, p.fracsize);

	  p.fracsize += (p.exponent + to_shift) / BITS_PER_MP_LIMB;

	}

      else

	{

	  cy = __mpn_lshift (p.frac +

			     (p.exponent + to_shift) / BITS_PER_MP_LIMB,

			     fp_input, p.fracsize,

			     (p.exponent + to_shift) % BITS_PER_MP_LIMB);

	  p.fracsize += (p.exponent + to_shift) / BITS_PER_MP_LIMB;

	  if (cy)

	    p.frac[p.fracsize++] = cy;

	}

      MPN_ZERO (p.frac, (p.exponent + to_shift) / BITS_PER_MP_LIMB);

      assert (powers > &_fpioconst_pow10[0]);

      do

	{

	  --powers;

	  /* The number of the product of two binary numbers with n and m

	     bits respectively has m+n or m+n-1 bits.	*/

	  if (p.exponent >= scaleexpo + powers->p_expo - 1)

	    {

	      if (p.scalesize == 0)

		{

#if __HAVE_DISTINCT_FLOAT128

		  if ((FLT128_MANT_DIG

			    > _FPIO_CONST_OFFSET * BITS_PER_MP_LIMB)

			   && info->is_binary128)

		    {

#define _FLT128_FPIO_CONST_SHIFT \

  (((FLT128_MANT_DIG + BITS_PER_MP_LIMB - 1) / BITS_PER_MP_LIMB) \

   - _FPIO_CONST_OFFSET)

		      /* 64bit const offset is not enough for

			 IEEE 854 quad long double (_Float128).  */

		      p.tmpsize = powers->arraysize + _FLT128_FPIO_CONST_SHIFT;

		      memcpy (p.tmp + _FLT128_FPIO_CONST_SHIFT,

			      &__tens[powers->arrayoff],

			      p.tmpsize * sizeof (mp_limb_t));

		      MPN_ZERO (p.tmp, _FLT128_FPIO_CONST_SHIFT);

		      /* Adjust p.exponent, as scaleexpo will be this much

			 bigger too.  */

		      p.exponent += _FLT128_FPIO_CONST_SHIFT * BITS_PER_MP_LIMB;

		    }

		  else

#endif /* __HAVE_DISTINCT_FLOAT128 */

#ifndef __NO_LONG_DOUBLE_MATH

		  if (LDBL_MANT_DIG > _FPIO_CONST_OFFSET * BITS_PER_MP_LIMB

		      && info->is_long_double)

		    {

#define _FPIO_CONST_SHIFT \

  (((LDBL_MANT_DIG + BITS_PER_MP_LIMB - 1) / BITS_PER_MP_LIMB) \

   - _FPIO_CONST_OFFSET)

		      /* 64bit const offset is not enough for

			 IEEE quad long double.  */

		      p.tmpsize = powers->arraysize + _FPIO_CONST_SHIFT;

		      memcpy (p.tmp + _FPIO_CONST_SHIFT,

			      &__tens[powers->arrayoff],

			      p.tmpsize * sizeof (mp_limb_t));

		      MPN_ZERO (p.tmp, _FPIO_CONST_SHIFT);

		      /* Adjust p.exponent, as scaleexpo will be this much

			 bigger too.  */

		      p.exponent += _FPIO_CONST_SHIFT * BITS_PER_MP_LIMB;

		    }

		  else

#endif

		    {

		      p.tmpsize = powers->arraysize;

		      memcpy (p.tmp, &__tens[powers->arrayoff],

			      p.tmpsize * sizeof (mp_limb_t));

		    }

		}

	      else

		{

		  cy = __mpn_mul (p.tmp, p.scale, p.scalesize,

				  &__tens[powers->arrayoff

					 + _FPIO_CONST_OFFSET],

				  powers->arraysize - _FPIO_CONST_OFFSET);

		  p.tmpsize = p.scalesize +

		    powers->arraysize - _FPIO_CONST_OFFSET;

		  if (cy == 0)

		    --p.tmpsize;

		}

	      if (MPN_GE (p.frac, p.tmp))

		{

		  int cnt;

		  MPN_ASSIGN (p.scale, p.tmp);

		  count_leading_zeros (cnt, p.scale[p.scalesize - 1]);

		  scaleexpo = (p.scalesize - 2) * BITS_PER_MP_LIMB - cnt - 1;

		  exp10 |= 1 << explog;

		}

	    }

	  --explog;

	}

      while (powers > &_fpioconst_pow10[0]);

      p.exponent = exp10;

      /* Optimize number representations.  We want to represent the numbers

	 with the lowest number of bytes possible without losing any

	 bytes. Also the highest bit in the scaling factor has to be set

	 (this is a requirement of the MPN division routines).  */

      if (p.scalesize > 0)

	{

	  /* Determine minimum number of zero bits at the end of

	     both numbers.  */

	  for (i = 0; p.scale[i] == 0 && p.frac[i] == 0; i++)

	    ;

	  /* Determine number of bits the scaling factor is misplaced.	*/

	  count_leading_zeros (cnt_h, p.scale[p.scalesize - 1]);

	  if (cnt_h == 0)

	    {

	      /* The highest bit of the scaling factor is already set.	So

		 we only have to remove the trailing empty limbs.  */

	      if (i > 0)

		{

		  MPN_COPY_INCR (p.scale, p.scale + i, p.scalesize - i);

		  p.scalesize -= i;

		  MPN_COPY_INCR (p.frac, p.frac + i, p.fracsize - i);

		  p.fracsize -= i;

		}

	    }

	  else

	    {

	      if (p.scale[i] != 0)

		{

		  count_trailing_zeros (cnt_l, p.scale[i]);

		  if (p.frac[i] != 0)

		    {

		      int cnt_l2;

		      count_trailing_zeros (cnt_l2, p.frac[i]);

		      if (cnt_l2 < cnt_l)

			cnt_l = cnt_l2;

		    }

		}

	      else

		count_trailing_zeros (cnt_l, p.frac[i]);

	      /* Now shift the numbers to their optimal position.  */

	      if (i == 0 && BITS_PER_MP_LIMB - cnt_h > cnt_l)

		{

		  /* We cannot save any memory.	 So just roll both numbers

		     so that the scaling factor has its highest bit set.  */

		  (void) __mpn_lshift (p.scale, p.scale, p.scalesize, cnt_h);

		  cy = __mpn_lshift (p.frac, p.frac, p.fracsize, cnt_h);

		  if (cy != 0)

		    p.frac[p.fracsize++] = cy;

		}

	      else if (BITS_PER_MP_LIMB - cnt_h <= cnt_l)

		{

		  /* We can save memory by removing the trailing zero limbs

		     and by packing the non-zero limbs which gain another

		     free one. */

		  (void) __mpn_rshift (p.scale, p.scale + i, p.scalesize - i,

				       BITS_PER_MP_LIMB - cnt_h);

		  p.scalesize -= i + 1;

		  (void) __mpn_rshift (p.frac, p.frac + i, p.fracsize - i,

				       BITS_PER_MP_LIMB - cnt_h);

		  p.fracsize -= p.frac[p.fracsize - i - 1] == 0 ? i + 1 : i;

		}

	      else

		{

		  /* We can only save the memory of the limbs which are zero.

		     The non-zero parts occupy the same number of limbs.  */

		  (void) __mpn_rshift (p.scale, p.scale + (i - 1),

				       p.scalesize - (i - 1),

				       BITS_PER_MP_LIMB - cnt_h);

		  p.scalesize -= i;

		  (void) __mpn_rshift (p.frac, p.frac + (i - 1),

				       p.fracsize - (i - 1),

				       BITS_PER_MP_LIMB - cnt_h);

		  p.fracsize -=

		    p.frac[p.fracsize - (i - 1) - 1] == 0 ? i : i - 1;

		}

	    }

	}

    }

  else if (p.exponent < 0)

    {

      /* |FP| < 1.0.  */

      int exp10 = 0;

      int explog;

#if __HAVE_DISTINCT_FLOAT128

      if (info->is_binary128)

	explog = FLT128_MAX_10_EXP_LOG;

      else

	explog = LDBL_MAX_10_EXP_LOG;

#else

      explog = LDBL_MAX_10_EXP_LOG;

#endif

      const struct mp_power *powers = &_fpioconst_pow10[explog + 1];

      /* Now shift the input value to its right place.	*/

      cy = __mpn_lshift (p.frac, fp_input, p.fracsize, to_shift);

      p.frac[p.fracsize++] = cy;

      assert (cy == 1 || (p.frac[p.fracsize - 2] == 0 && p.frac[0] == 0));

      p.expsign = 1;

      p.exponent = -p.exponent;

      assert (powers != &_fpioconst_pow10[0]);

      do

	{

	  --powers;

	  if (p.exponent >= powers->m_expo)

	    {

	      int i, incr, cnt_h, cnt_l;

	      mp_limb_t topval[2];

	      /* The __mpn_mul function expects the first argument to be

		 bigger than the second.  */

	      if (p.fracsize < powers->arraysize - _FPIO_CONST_OFFSET)

		cy = __mpn_mul (p.tmp, &__tens[powers->arrayoff

					    + _FPIO_CONST_OFFSET],

				powers->arraysize - _FPIO_CONST_OFFSET,

				p.frac, p.fracsize);

	      else

		cy = __mpn_mul (p.tmp, p.frac, p.fracsize,

				&__tens[powers->arrayoff + _FPIO_CONST_OFFSET],

				powers->arraysize - _FPIO_CONST_OFFSET);

	      p.tmpsize = p.fracsize + powers->arraysize - _FPIO_CONST_OFFSET;

	      if (cy == 0)

		--p.tmpsize;

	      count_leading_zeros (cnt_h, p.tmp[p.tmpsize - 1]);

	      incr = (p.tmpsize - p.fracsize) * BITS_PER_MP_LIMB

		     + BITS_PER_MP_LIMB - 1 - cnt_h;

	      assert (incr <= powers->p_expo);

	      /* If we increased the p.exponent by exactly 3 we have to test

		 for overflow.	This is done by comparing with 10 shifted

		 to the right position.	 */

	      if (incr == p.exponent + 3)

		{

		  if (cnt_h <= BITS_PER_MP_LIMB - 4)

		    {

		      topval[0] = 0;

		      topval[1]

			= ((mp_limb_t) 10) << (BITS_PER_MP_LIMB - 4 - cnt_h);

		    }

		  else

		    {

		      topval[0] = ((mp_limb_t) 10) << (BITS_PER_MP_LIMB - 4);

		      topval[1] = 0;

		      (void) __mpn_lshift (topval, topval, 2,

					   BITS_PER_MP_LIMB - cnt_h);

		    }

		}

	      /* We have to be careful when multiplying the last factor.

		 If the result is greater than 1.0 be have to test it

		 against 10.0.  If it is greater or equal to 10.0 the

		 multiplication was not valid.  This is because we cannot

		 determine the number of bits in the result in advance.  */

	      if (incr < p.exponent + 3

		  || (incr == p.exponent + 3 &&

		      (p.tmp[p.tmpsize - 1] < topval[1]

		       || (p.tmp[p.tmpsize - 1] == topval[1]

			   && p.tmp[p.tmpsize - 2] < topval[0]))))

		{

		  /* The factor is right.  Adapt binary and decimal

		     exponents.	 */

		  p.exponent -= incr;

		  exp10 |= 1 << explog;

		  /* If this factor yields a number greater or equal to

		     1.0, we must not shift the non-fractional digits down. */

		  if (p.exponent < 0)

		    cnt_h += -p.exponent;

		  /* Now we optimize the number representation.	 */

		  for (i = 0; p.tmp[i] == 0; ++i);

		  if (cnt_h == BITS_PER_MP_LIMB - 1)

		    {

		      MPN_COPY (p.frac, p.tmp + i, p.tmpsize - i);

		      p.fracsize = p.tmpsize - i;

		    }

		  else

		    {

		      count_trailing_zeros (cnt_l, p.tmp[i]);

		      /* Now shift the numbers to their optimal position.  */

		      if (i == 0 && BITS_PER_MP_LIMB - 1 - cnt_h > cnt_l)

			{

			  /* We cannot save any memory.	 Just roll the

			     number so that the leading digit is in a

			     separate limb.  */

			  cy = __mpn_lshift (p.frac, p.tmp, p.tmpsize,

			    cnt_h + 1);

			  p.fracsize = p.tmpsize + 1;

			  p.frac[p.fracsize - 1] = cy;

			}

		      else if (BITS_PER_MP_LIMB - 1 - cnt_h <= cnt_l)

			{

			  (void) __mpn_rshift (p.frac, p.tmp + i, p.tmpsize - i,

					       BITS_PER_MP_LIMB - 1 - cnt_h);

			  p.fracsize = p.tmpsize - i;

			}

		      else

			{

			  /* We can only save the memory of the limbs which

			     are zero.	The non-zero parts occupy the same

			     number of limbs.  */

			  (void) __mpn_rshift (p.frac, p.tmp + (i - 1),

					       p.tmpsize - (i - 1),

					       BITS_PER_MP_LIMB - 1 - cnt_h);

			  p.fracsize = p.tmpsize - (i - 1);

			}

		    }

		}

	    }

	  --explog;

	}

      while (powers != &_fpioconst_pow10[1] && p.exponent > 0);

      /* All factors but 10^-1 are tested now.	*/

      if (p.exponent > 0)

	{

	  int cnt_l;

	  cy = __mpn_mul_1 (p.tmp, p.frac, p.fracsize, 10);

	  p.tmpsize = p.fracsize;

	  assert (cy == 0 || p.tmp[p.tmpsize - 1] < 20);

	  count_trailing_zeros (cnt_l, p.tmp[0]);

	  if (cnt_l < MIN (4, p.exponent))

	    {

	      cy = __mpn_lshift (p.frac, p.tmp, p.tmpsize,

				 BITS_PER_MP_LIMB - MIN (4, p.exponent));

	      if (cy != 0)

		p.frac[p.tmpsize++] = cy;

	    }

	  else

	    (void) __mpn_rshift (p.frac, p.tmp, p.tmpsize, MIN (4, p.exponent));

	  p.fracsize = p.tmpsize;

	  exp10 |= 1;

	  assert (p.frac[p.fracsize - 1] < 10);

	}

      p.exponent = exp10;

    }

  else

    {

      /* This is a special case.  We don't need a factor because the

	 numbers are in the range of 1.0 <= |fp| < 8.0.  We simply

	 shift it to the right place and divide it by 1.0 to get the

	 leading digit.	 (Of course this division is not really made.)	*/

      assert (0 <= p.exponent && p.exponent < 3 &&

	      p.exponent + to_shift < BITS_PER_MP_LIMB);

      /* Now shift the input value to its right place.	*/

      cy = __mpn_lshift (p.frac, fp_input, p.fracsize, (p.exponent + to_shift));

      p.frac[p.fracsize++] = cy;

      p.exponent = 0;

    }

  {

    int width = info->width;

    wchar_t *wstartp, *wcp;

    size_t chars_needed;

    int expscale;

    int intdig_max, intdig_no = 0;

    int fracdig_min;

    int fracdig_max;

    int dig_max;

    int significant;

    int ngroups = 0;

    char spec = _tolower (info->spec);

    if (spec == 'e')

      {

	p.type = info->spec;

	intdig_max = 1;

	fracdig_min = fracdig_max = info->prec < 0 ? 6 : info->prec;

	chars_needed = 1 + 1 + (size_t) fracdig_max + 1 + 1 + 4;

	/*	       d   .	 ddd	     e	 +-  ddd  */

	dig_max = INT_MAX;		/* Unlimited.  */

	significant = 1;		/* Does not matter here.  */

      }

    else if (spec == 'f')

      {

	p.type = 'f';

	fracdig_min = fracdig_max = info->prec < 0 ? 6 : info->prec;

	dig_max = INT_MAX;		/* Unlimited.  */

	significant = 1;		/* Does not matter here.  */

	if (p.expsign == 0)

	  {

	    intdig_max = p.exponent + 1;

	    /* This can be really big!	*/  /* XXX Maybe malloc if too big? */

	    chars_needed = (size_t) p.exponent + 1 + 1 + (size_t) fracdig_max;

	  }

	else

	  {

	    intdig_max = 1;

	    chars_needed = 1 + 1 + (size_t) fracdig_max;

	  }

      }

    else

      {

	dig_max = info->prec < 0 ? 6 : (info->prec == 0 ? 1 : info->prec);

	if ((p.expsign == 0 && p.exponent >= dig_max)

	    || (p.expsign != 0 && p.exponent > 4))

	  {

	    if ('g' - 'G' == 'e' - 'E')

	      p.type = 'E' + (info->spec - 'G');

	    else

	      p.type = isupper (info->spec) ? 'E' : 'e';

	    fracdig_max = dig_max - 1;

	    intdig_max = 1;

	    chars_needed = 1 + 1 + (size_t) fracdig_max + 1 + 1 + 4;

	  }

	else

	  {

	    p.type = 'f';

	    intdig_max = p.expsign == 0 ? p.exponent + 1 : 0;

	    fracdig_max = dig_max - intdig_max;