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glibc  2.9
Defines | Functions
efgcvt_r.c File Reference
#include <errno.h>
#include <float.h>
#include <stdio.h>
#include <string.h>
#include <ctype.h>
#include <math.h>
#include <stdlib.h>
#include <sys/param.h>
#include <math_ldbl_opt.h>
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Go to the source code of this file.

Defines

#define FLOAT_TYPE   double
#define FUNC_PREFIX
#define FLOAT_FMT_FLAG
#define FLOAT_NAME_EXT
#define FLOAT_MIN_10_EXP   DBL_MIN_10_EXP
#define NDIGIT_MAX   (lrint (ceil (M_LN2 / M_LN10 * DBL_MANT_DIG + 1.0)))
#define FLOAT_MIN_10_NORM   exp10 (DBL_MIN_10_EXP)
#define APPEND(a, b)   APPEND2 (a, b)
#define APPEND2(a, b)   a##b
#define __APPEND(a, b)   __APPEND2 (a, b)
#define __APPEND2(a, b)   __##a##b
#define FLOOR   APPEND(floor, FLOAT_NAME_EXT)
#define FABS   APPEND(fabs, FLOAT_NAME_EXT)
#define LOG10   APPEND(log10, FLOAT_NAME_EXT)
#define EXP   APPEND(exp, FLOAT_NAME_EXT)
#define cvt_symbol(symbol)   strong_alias (__APPEND (FUNC_PREFIX, symbol), APPEND (FUNC_PREFIX, symbol))

Functions

int __APPEND (FUNC_PREFIX, fcvt_r)
int __APPEND (FUNC_PREFIX, ecvt_r)
 cvt_symbol (fcvt_r)
 cvt_symbol (ecvt_r)

Define Documentation

#define __APPEND (   a,
  b 
)    __APPEND2 (a, b)

Definition at line 66 of file efgcvt_r.c.

#define __APPEND2 (   a,
  b 
)    __##a##b

Definition at line 67 of file efgcvt_r.c.

#define APPEND (   a,
  b 
)    APPEND2 (a, b)

Definition at line 64 of file efgcvt_r.c.

#define APPEND2 (   a,
  b 
)    a##b

Definition at line 65 of file efgcvt_r.c.

#define cvt_symbol (   symbol)    strong_alias (__APPEND (FUNC_PREFIX, symbol), APPEND (FUNC_PREFIX, symbol))

Definition at line 261 of file efgcvt_r.c.

#define EXP   APPEND(exp, FLOAT_NAME_EXT)

Definition at line 72 of file efgcvt_r.c.

#define FABS   APPEND(fabs, FLOAT_NAME_EXT)

Definition at line 70 of file efgcvt_r.c.

#define FLOAT_FMT_FLAG

Definition at line 34 of file efgcvt_r.c.

Definition at line 36 of file efgcvt_r.c.

#define FLOAT_MIN_10_NORM   exp10 (DBL_MIN_10_EXP)

Definition at line 58 of file efgcvt_r.c.

#define FLOAT_NAME_EXT

Definition at line 35 of file efgcvt_r.c.

#define FLOAT_TYPE   double

Definition at line 32 of file efgcvt_r.c.

#define FLOOR   APPEND(floor, FLOAT_NAME_EXT)

Definition at line 69 of file efgcvt_r.c.

#define FUNC_PREFIX

Definition at line 33 of file efgcvt_r.c.

#define LOG10   APPEND(log10, FLOAT_NAME_EXT)

Definition at line 71 of file efgcvt_r.c.

#define NDIGIT_MAX   (lrint (ceil (M_LN2 / M_LN10 * DBL_MANT_DIG + 1.0)))

Definition at line 47 of file efgcvt_r.c.


Function Documentation

int __APPEND ( FUNC_PREFIX  ,
fcvt_r   
)

Definition at line 76 of file efgcvt_r.c.

{
  ssize_t n;
  ssize_t i;
  int left;

  if (buf == NULL)
    {
      __set_errno (EINVAL);
      return -1;
    }

  left = 0;
  if (isfinite (value))
    {
      *sign = signbit (value) != 0;
      if (*sign)
       value = -value;

      if (ndigit < 0)
       {
         /* Rounding to the left of the decimal point.  */
         while (ndigit < 0)
           {
             FLOAT_TYPE new_value = value * 0.1;

             if (new_value < 1.0)
              {
                ndigit = 0;
                break;
              }

             value = new_value;
             ++left;
             ++ndigit;
           }
       }
    }
  else
    /* Value is Inf or NaN.  */
    *sign = 0;

  n = __snprintf (buf, len, "%.*" FLOAT_FMT_FLAG "f", MIN (ndigit, NDIGIT_MAX),
                value);
  /* Check for a too small buffer.  */
  if (n >= (ssize_t) len)
    return -1;

  i = 0;
  while (i < n && isdigit (buf[i]))
    ++i;
  *decpt = i;

  if (i == 0)
    /* Value is Inf or NaN.  */
    return 0;

  if (i < n)
    {
      do
       ++i;
      while (i < n && !isdigit (buf[i]));

      if (*decpt == 1 && buf[0] == '0' && value != 0.0)
       {
         /* We must not have leading zeroes.  Strip them all out and
            adjust *DECPT if necessary.  */
         --*decpt;
         while (i < n && buf[i] == '0')
           {
             --*decpt;
             ++i;
           }
       }

      memmove (&buf[MAX (*decpt, 0)], &buf[i], n - i);
      buf[n - (i - MAX (*decpt, 0))] = '\0';
    }

  if (left)
    {
      *decpt += left;
      if ((ssize_t) --len > n)
       {
         while (left-- > 0 && n < (ssize_t) len)
           buf[n++] = '0';
         buf[n] = '\0';
       }
    }

  return 0;
}

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int __APPEND ( FUNC_PREFIX  ,
ecvt_r   
)

Definition at line 174 of file efgcvt_r.c.

{
  int exponent = 0;

  if (isfinite (value) && value != 0.0)
    {
      /* Slow code that doesn't require -lm functions.  */
      FLOAT_TYPE d;
      FLOAT_TYPE f = 1.0;
      if (value < 0.0)
       d = -value;
      else
       d = value;
      /* For denormalized numbers the d < 1.0 case below won't work,
        as f can overflow to +Inf.  */
      if (d < FLOAT_MIN_10_NORM)
       {
         value /= FLOAT_MIN_10_NORM;
         if (value < 0.0)
           d = -value;
         else
           d = value;
         exponent += FLOAT_MIN_10_EXP;
       }
      if (d < 1.0)
       {
         do
           {
             f *= 10.0;
             --exponent;
           }
         while (d * f < 1.0);

         value *= f;
       }
      else if (d >= 10.0)
       {
         do
           {
             f *= 10;
             ++exponent;
           }
         while (d >= f * 10.0);

         value /= f;
       }
    }
  else if (value == 0.0)
    /* SUSv2 leaves it unspecified whether *DECPT is 0 or 1 for 0.0.
       This could be changed to -1 if we want to return 0.  */
    exponent = 0;

  if (ndigit <= 0 && len > 0)
    {
      buf[0] = '\0';
      *decpt = 1;
      *sign = isfinite (value) ? signbit (value) != 0 : 0;
    }
  else
    if (__APPEND (FUNC_PREFIX, fcvt_r) (value, MIN (ndigit, NDIGIT_MAX) - 1,
                                   decpt, sign, buf, len))
      return -1;

  *decpt += exponent;
  return 0;
}
cvt_symbol ( fcvt_r  )
cvt_symbol ( ecvt_r  )