write.c

gcc-fortran,linux使用fortran的编译软件。很好用的。

/* Copyright (C) 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
   Contributed by Andy Vaught
   Namelist output contibuted by Paul Thomas

This file is part of the GNU Fortran 95 runtime library (libgfortran).

Libgfortran is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.

In addition to the permissions in the GNU General Public License, the
Free Software Foundation gives you unlimited permission to link the
compiled version of this file into combinations with other programs,
and to distribute those combinations without any restriction coming
from the use of this file.  (The General Public License restrictions
do apply in other respects; for example, they cover modification of
the file, and distribution when not linked into a combine
executable.)

Libgfortran 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 General Public License for more details.

You should have received a copy of the GNU General Public License
along with Libgfortran; see the file COPYING.  If not, write to
the Free Software Foundation, 51 Franklin Street, Fifth Floor,
Boston, MA 02110-1301, USA.  */

#include "config.h"
#include <assert.h>
#include <string.h>
#include <ctype.h>
#include <float.h>
#include <stdio.h>
#include <stdlib.h>
#include "libgfortran.h"
#include "io.h"

#define star_fill(p, n) memset(p, '*', n)


typedef enum
{ SIGN_NONE, SIGN_MINUS, SIGN_PLUS }
sign_t;


void
write_a (st_parameter_dt *dtp, const fnode *f, const char *source, int len)
{
  int wlen;
  char *p;

  wlen = f->u.string.length < 0 ? len : f->u.string.length;

  p = write_block (dtp, wlen);
  if (p == NULL)
    return;

  if (wlen < len)
    memcpy (p, source, wlen);
  else
    {
      memset (p, ' ', wlen - len);
      memcpy (p + wlen - len, source, len);
    }
}

static GFC_INTEGER_LARGEST
extract_int (const void *p, int len)
{
  GFC_INTEGER_LARGEST i = 0;

  if (p == NULL)
    return i;

  switch (len)
    {
    case 1:
      {
	GFC_INTEGER_1 tmp;
	memcpy ((void *) &tmp, p, len);
	i = tmp;
      }
      break;
    case 2:
      {
	GFC_INTEGER_2 tmp;
	memcpy ((void *) &tmp, p, len);
	i = tmp;
      }
      break;
    case 4:
      {
	GFC_INTEGER_4 tmp;
	memcpy ((void *) &tmp, p, len);
	i = tmp;
      }
      break;
    case 8:
      {
	GFC_INTEGER_8 tmp;
	memcpy ((void *) &tmp, p, len);
	i = tmp;
      }
      break;
#ifdef HAVE_GFC_INTEGER_16
    case 16:
      {
	GFC_INTEGER_16 tmp;
	memcpy ((void *) &tmp, p, len);
	i = tmp;
      }
      break;
#endif
    default:
      internal_error (NULL, "bad integer kind");
    }

  return i;
}

static GFC_UINTEGER_LARGEST
extract_uint (const void *p, int len)
{
  GFC_UINTEGER_LARGEST i = 0;

  if (p == NULL)
    return i;

  switch (len)
    {
    case 1:
      {
	GFC_INTEGER_1 tmp;
	memcpy ((void *) &tmp, p, len);
	i = (GFC_UINTEGER_1) tmp;
      }
      break;
    case 2:
      {
	GFC_INTEGER_2 tmp;
	memcpy ((void *) &tmp, p, len);
	i = (GFC_UINTEGER_2) tmp;
      }
      break;
    case 4:
      {
	GFC_INTEGER_4 tmp;
	memcpy ((void *) &tmp, p, len);
	i = (GFC_UINTEGER_4) tmp;
      }
      break;
    case 8:
      {
	GFC_INTEGER_8 tmp;
	memcpy ((void *) &tmp, p, len);
	i = (GFC_UINTEGER_8) tmp;
      }
      break;
#ifdef HAVE_GFC_INTEGER_16
    case 16:
      {
	GFC_INTEGER_16 tmp;
	memcpy ((void *) &tmp, p, len);
	i = (GFC_UINTEGER_16) tmp;
      }
      break;
#endif
    default:
      internal_error (NULL, "bad integer kind");
    }

  return i;
}

static GFC_REAL_LARGEST
extract_real (const void *p, int len)
{
  GFC_REAL_LARGEST i = 0;
  switch (len)
    {
    case 4:
      {
	GFC_REAL_4 tmp;
	memcpy ((void *) &tmp, p, len);
	i = tmp;
      }
      break;
    case 8:
      {
	GFC_REAL_8 tmp;
	memcpy ((void *) &tmp, p, len);
	i = tmp;
      }
      break;
#ifdef HAVE_GFC_REAL_10
    case 10:
      {
	GFC_REAL_10 tmp;
	memcpy ((void *) &tmp, p, len);
	i = tmp;
      }
      break;
#endif
#ifdef HAVE_GFC_REAL_16
    case 16:
      {
	GFC_REAL_16 tmp;
	memcpy ((void *) &tmp, p, len);
	i = tmp;
      }
      break;
#endif
    default:
      internal_error (NULL, "bad real kind");
    }
  return i;
}


/* Given a flag that indicate if a value is negative or not, return a
   sign_t that gives the sign that we need to produce.  */

static sign_t
calculate_sign (st_parameter_dt *dtp, int negative_flag)
{
  sign_t s = SIGN_NONE;

  if (negative_flag)
    s = SIGN_MINUS;
  else
    switch (dtp->u.p.sign_status)
      {
      case SIGN_SP:
	s = SIGN_PLUS;
	break;
      case SIGN_SS:
	s = SIGN_NONE;
	break;
      case SIGN_S:
	s = options.optional_plus ? SIGN_PLUS : SIGN_NONE;
	break;
      }

  return s;
}


/* Returns the value of 10**d.  */

static GFC_REAL_LARGEST
calculate_exp (int d)
{
  int i;
  GFC_REAL_LARGEST r = 1.0;

  for (i = 0; i< (d >= 0 ? d : -d); i++)
    r *= 10;

  r = (d >= 0) ? r : 1.0 / r;

  return r;
}


/* Generate corresponding I/O format for FMT_G output.
   The rules to translate FMT_G to FMT_E or FMT_F from DEC fortran
   LRM (table 11-2, Chapter 11, "I/O Formatting", P11-25) is:

   Data Magnitude                              Equivalent Conversion
   0< m < 0.1-0.5*10**(-d-1)                   Ew.d[Ee]
   m = 0                                       F(w-n).(d-1), n' '
   0.1-0.5*10**(-d-1)<= m < 1-0.5*10**(-d)     F(w-n).d, n' '
   1-0.5*10**(-d)<= m < 10-0.5*10**(-d+1)      F(w-n).(d-1), n' '
   10-0.5*10**(-d+1)<= m < 100-0.5*10**(-d+2)  F(w-n).(d-2), n' '
   ................                           ..........
   10**(d-1)-0.5*10**(-1)<= m <10**d-0.5       F(w-n).0,n(' ')
   m >= 10**d-0.5                              Ew.d[Ee]

   notes: for Gw.d ,  n' ' means 4 blanks
          for Gw.dEe, n' ' means e+2 blanks  */

static fnode *
calculate_G_format (st_parameter_dt *dtp, const fnode *f,
		    GFC_REAL_LARGEST value, int *num_blank)
{
  int e = f->u.real.e;
  int d = f->u.real.d;
  int w = f->u.real.w;
  fnode *newf;
  GFC_REAL_LARGEST m, exp_d;
  int low, high, mid;
  int ubound, lbound;

  newf = get_mem (sizeof (fnode));

  /* Absolute value.  */
  m = (value > 0.0) ? value : -value;

  /* In case of the two data magnitude ranges,
     generate E editing, Ew.d[Ee].  */
  exp_d = calculate_exp (d);
  if ((m > 0.0 && m < 0.1 - 0.05 / exp_d) || (m >= exp_d - 0.5 ) ||
      ((m == 0.0) && !(compile_options.allow_std & GFC_STD_F2003)))
    {
      newf->format = FMT_E;
      newf->u.real.w = w;
      newf->u.real.d = d;
      newf->u.real.e = e;
      *num_blank = 0;
      return newf;
    }

  /* Use binary search to find the data magnitude range.  */
  mid = 0;
  low = 0;
  high = d + 1;
  lbound = 0;
  ubound = d + 1;

  while (low <= high)
    {
      GFC_REAL_LARGEST temp;
      mid = (low + high) / 2;

      /* 0.1 * 10**mid - 0.5 * 10**(mid-d-1)  */
      temp = 0.1 * calculate_exp (mid) - 0.5 * calculate_exp (mid - d - 1);

      if (m < temp)
        {
          ubound = mid;
          if (ubound == lbound + 1)
            break;
          high = mid - 1;
        }
      else if (m > temp)
        {
          lbound = mid;
          if (ubound == lbound + 1)
            {
              mid ++;
              break;
            }
          low = mid + 1;
        }
      else
        break;
    }

  /* Pad with blanks where the exponent would be.  */
  if (e < 0)
    *num_blank = 4;
  else
    *num_blank = e + 2;

  /* Generate the F editing. F(w-n).(-(mid-d-1)), n' '.  */
  newf->format = FMT_F;
  newf->u.real.w = f->u.real.w - *num_blank;

  /* Special case.  */
  if (m == 0.0)
    newf->u.real.d = d - 1;
  else
    newf->u.real.d = - (mid - d - 1);

  /* For F editing, the scale factor is ignored.  */
  dtp->u.p.scale_factor = 0;
  return newf;
}


/* Output a real number according to its format which is FMT_G free.  */

static void
output_float (st_parameter_dt *dtp, const fnode *f, GFC_REAL_LARGEST value)
{
  /* This must be large enough to accurately hold any value.  */
  char buffer[32];
  char *out;
  char *digits;
  int e;
  char expchar;
  format_token ft;
  int w;
  int d;
  int edigits;
  int ndigits;
  /* Number of digits before the decimal point.  */
  int nbefore;
  /* Number of zeros after the decimal point.  */
  int nzero;
  /* Number of digits after the decimal point.  */
  int nafter;
  /* Number of zeros after the decimal point, whatever the precision.  */
  int nzero_real;
  int leadzero;
  int nblanks;
  int i;
  sign_t sign;
  double abslog;

  ft = f->format;
  w = f->u.real.w;
  d = f->u.real.d;

  nzero_real = -1;


  /* We should always know the field width and precision.  */
  if (d < 0)
    internal_error (&dtp->common, "Unspecified precision");

  /* Use sprintf to print the number in the format +D.DDDDe+ddd
     For an N digit exponent, this gives us (32-6)-N digits after the
     decimal point, plus another one before the decimal point.  */
  sign = calculate_sign (dtp, value < 0.0);
  if (value < 0)
    value = -value;

  /* Printf always prints at least two exponent digits.  */
  if (value == 0)
    edigits = 2;
  else
    {
#if defined(HAVE_GFC_REAL_10) || defined(HAVE_GFC_REAL_16)
      abslog = fabs((double) log10l(value));
#else
      abslog = fabs(log10(value));
#endif
      if (abslog < 100)
	edigits = 2;
      else
        edigits = 1 + (int) log10(abslog);
    }

  if (ft == FMT_F || ft == FMT_EN
      || ((ft == FMT_D || ft == FMT_E) && dtp->u.p.scale_factor != 0))
    {
      /* Always convert at full precision to avoid double rounding.  */
      ndigits = 27 - edigits;
    }
  else
    {
      /* We know the number of digits, so can let printf do the rounding
	 for us.  */
      if (ft == FMT_ES)
	ndigits = d + 1;
      else
	ndigits = d;
      if (ndigits > 27 - edigits)
	ndigits = 27 - edigits;
    }

  /* #   The result will always contain a decimal point, even if no
   *     digits follow it
   *
   * -   The converted value is to be left adjusted on the field boundary
   *
   * +   A sign (+ or -) always be placed before a number
   *
   * 31  minimum field width
   *
   * *   (ndigits-1) is used as the precision
   *
   *   e format: [-]d.ddde±dd where there is one digit before the
   *   decimal-point character and the number of digits after it is
   *   equal to the precision. The exponent always contains at least two
   *   digits; if the value is zero, the exponent is 00.
   */
  sprintf (buffer, "%+-#31.*" GFC_REAL_LARGEST_FORMAT "e",
           ndigits - 1, value);

  /* Check the resulting string has punctuation in the correct places.  */
  if (buffer[2] != '.' || buffer[ndigits + 2] != 'e')
      internal_error (&dtp->common, "printf is broken");

  /* Read the exponent back in.  */
  e = atoi (&buffer[ndigits + 3]) + 1;

  /* Make sure zero comes out as 0.0e0.  */
  if (value == 0.0)
    e = 0;

  /* Normalize the fractional component.  */
  buffer[2] = buffer[1];
  digits = &buffer[2];

  /* Figure out where to place the decimal point.  */
  switch (ft)
    {
    case FMT_F:
      nbefore = e + dtp->u.p.scale_factor;
      if (nbefore < 0)
	{
	  nzero = -nbefore;
          nzero_real = nzero;
	  if (nzero > d)
	    nzero = d;
	  nafter = d - nzero;
	  nbefore = 0;
	}
      else
	{
	  nzero = 0;
	  nafter = d;
	}
      expchar = 0;
      break;

    case FMT_E:
    case FMT_D:
      i = dtp->u.p.scale_factor;
      if (value != 0.0)
	e -= i;
      if (i < 0)
	{
	  nbefore = 0;
	  nzero = -i;
	  nafter = d + i;
	}
      else if (i > 0)
	{
	  nbefore = i;
	  nzero = 0;
	  nafter = (d - i) + 1;
	}
      else /* i == 0 */
	{
	  nbefore = 0;
	  nzero = 0;
	  nafter = d;
	}

      if (ft == FMT_E)
	expchar = 'E';
      else
	expchar = 'D';
      break;

    case FMT_EN:
      /* The exponent must be a multiple of three, with 1-3 digits before
	 the decimal point.  */
      if (value != 0.0)
        e--;
      if (e >= 0)
	nbefore = e % 3;
      else
	{
	  nbefore = (-e) % 3;
	  if (nbefore != 0)
	    nbefore = 3 - nbefore;
	}
      e -= nbefore;
      nbefore++;
      nzero = 0;
      nafter = d;
      expchar = 'E';
      break;

    case FMT_ES:
      if (value != 0.0)
        e--;
      nbefore = 1;
      nzero = 0;
      nafter = d;
      expchar = 'E';
      break;

    default:
      /* Should never happen.  */
      internal_error (&dtp->common, "Unexpected format token");
    }

  /* Round the value.  */
  if (nbefore + nafter == 0)
    {
      ndigits = 0;
      if (nzero_real == d && digits[0] >= '5')
        {
          /* We rounded to zero but shouldn't have */
          nzero--;
          nafter = 1;
          digits[0] = '1';
          ndigits = 1;
        }
    }
  else if (nbefore + nafter < ndigits)
    {
      ndigits = nbefore + nafter;
      i = ndigits;
      if (digits[i] >= '5')
	{
	  /* Propagate the carry.  */
	  for (i--; i >= 0; i--)
	    {
	      if (digits[i] != '9')
		{
		  digits[i]++;
		  break;
		}
	      digits[i] = '0';
	    }

	  if (i < 0)
	    {
	      /* The carry overflowed.  Fortunately we have some spare space
		 at the start of the buffer.  We may discard some digits, but
		 this is ok because we already know they are zero.  */
	      digits--;