glibc/stdlib/strfmon_l.c

/* Formatting a monetary value according to the given locale.
   Copyright (C) 1996-2018 Free Software Foundation, Inc.
   This file is part of the GNU C Library.
   Contributed by Ulrich Drepper <drepper@cygnus.com>, 1996.

   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/>.  */

#include <ctype.h>
#include <errno.h>
#include <langinfo.h>
#include <locale.h>
#include <monetary.h>
#include "../libio/libioP.h"
#include "../libio/strfile.h"
#include <printf.h>
#include <stdarg.h>
#include <stdio.h>
#include <string.h>
#include "../locale/localeinfo.h"


#define out_char(Ch)							      \
  do {									      \
    if (dest >= s + maxsize - 1)					      \
      {									      \
	__set_errno (E2BIG);						      \
	va_end (ap);							      \
	return -1;							      \
      }									      \
    *dest++ = (Ch);							      \
  } while (0)

#define out_string(String)						      \
  do {									      \
    const char *_s = (String);						      \
    while (*_s)								      \
      out_char (*_s++);							      \
  } while (0)

#define out_nstring(String, N)						      \
  do {									      \
    int _n = (N);							      \
    const char *_s = (String);						      \
    while (_n-- > 0)							      \
      out_char (*_s++);							      \
  } while (0)

#define to_digit(Ch) ((Ch) - '0')


/* We use this code also for the extended locale handling where the
   function gets as an additional argument the locale which has to be
   used.  To access the values we have to redefine the _NL_CURRENT
   macro.  */
#undef _NL_CURRENT
#define _NL_CURRENT(category, item) \
  (current->values[_NL_ITEM_INDEX (item)].string)


/* We have to overcome some problems with this implementation.  On the
   one hand the strfmon() function is specified in XPG4 and of course
   it has to follow this.  But on the other hand POSIX.2 specifies
   some information in the LC_MONETARY category which should be used,
   too.  Some of the information contradicts the information which can
   be specified in format string.  */
ssize_t
__vstrfmon_l (char *s, size_t maxsize, locale_t loc, const char *format,
	      va_list ap)
{
  struct __locale_data *current = loc->__locales[LC_MONETARY];
  _IO_strfile f;
  struct printf_info info;
  char *dest;			/* Pointer so copy the output.  */
  const char *fmt;		/* Pointer that walks through format.  */

  dest = s;
  fmt = format;

  /* Loop through the format-string.  */
  while (*fmt != '\0')
    {
      /* The floating-point value to output.  */
      union
      {
	double dbl;
	long double ldbl;
      }
      fpnum;
      int int_format;
      int print_curr_symbol;
      int left_prec;
      int left_pad;
      int right_prec;
      int group;
      char pad;
      int is_long_double;
      int p_sign_posn;
      int n_sign_posn;
      int sign_posn;
      int other_sign_posn;
      int left;
      int is_negative;
      int sep_by_space;
      int other_sep_by_space;
      int cs_precedes;
      int other_cs_precedes;
      const char *sign_string;
      const char *other_sign_string;
      int done;
      const char *currency_symbol;
      size_t currency_symbol_len;
      long int width;
      char *startp;
      const void *ptr;
      char space_char;

      /* Process all character which do not introduce a format
	 specification.  */
      if (*fmt != '%')
	{
	  out_char (*fmt++);
	  continue;
	}

      /* "%%" means a single '%' character.  */
      if (fmt[1] == '%')
	{
	  out_char (*++fmt);
	  ++fmt;
	  continue;
	}

      /* Defaults for formatting.  */
      int_format = 0;			/* Use international curr. symbol */
      print_curr_symbol = 1;		/* Print the currency symbol.  */
      left_prec = -1;			/* No left precision specified.  */
      right_prec = -1;			/* No right precision specified.  */
      group = 1;			/* Print digits grouped.  */
      pad = ' ';			/* Fill character is <SP>.  */
      is_long_double = 0;		/* Double argument by default.  */
      p_sign_posn = -2;			/* This indicates whether the */
      n_sign_posn = -2;			/* '(' flag is given.  */
      width = -1;			/* No width specified so far.  */
      left = 0;				/* Right justified by default.  */

      /* Parse group characters.  */
      while (1)
	{
	  switch (*++fmt)
	    {
	    case '=':			/* Set fill character.  */
	      pad = *++fmt;
	      if (pad == '\0')
		{
		  /* Premature EOS.  */
		  __set_errno (EINVAL);
		  return -1;
		}
	      continue;
	    case '^':			/* Don't group digits.  */
	      group = 0;
	      continue;
	    case '+':			/* Use +/- for sign of number.  */
	      if (n_sign_posn != -2)
		{
		  __set_errno (EINVAL);
		  return -1;
		}
	      p_sign_posn = *_NL_CURRENT (LC_MONETARY, P_SIGN_POSN);
	      n_sign_posn = *_NL_CURRENT (LC_MONETARY, N_SIGN_POSN);
	      continue;
	    case '(':			/* Use ( ) for negative sign.  */
	      if (n_sign_posn != -2)
		{
		  __set_errno (EINVAL);
		  return -1;
		}
	      p_sign_posn = 0;
	      n_sign_posn = 0;
	      continue;
	    case '!':			/* Don't print the currency symbol.  */
	      print_curr_symbol = 0;
	      continue;
	    case '-':			/* Print left justified.  */
	      left = 1;
	      continue;
	    default:
	      /* Will stop the loop.  */;
	    }
	  break;
	}

      if (isdigit (*fmt))
	{
	  /* Parse field width.  */
	  width = to_digit (*fmt);

	  while (isdigit (*++fmt))
	    {
	      int val = to_digit (*fmt);

	      if (width > LONG_MAX / 10
		  || (width == LONG_MAX && val > LONG_MAX % 10))
		{
		  __set_errno (E2BIG);
		  return -1;
		}

	      width = width * 10 + val;
	    }

	  /* If we don't have enough room for the demanded width we
	     can stop now and return an error.  */
	  if (width >= maxsize - (dest - s))
	    {
	      __set_errno (E2BIG);
	      return -1;
	    }
	}

      /* Recognize left precision.  */
      if (*fmt == '#')
	{
	  if (!isdigit (*++fmt))
	    {
	      __set_errno (EINVAL);
	      return -1;
	    }
	  left_prec = to_digit (*fmt);

	  while (isdigit (*++fmt))
	    {
	      left_prec *= 10;
	      left_prec += to_digit (*fmt);
	    }
	}

      /* Recognize right precision.  */
      if (*fmt == '.')
	{
	  if (!isdigit (*++fmt))
	    {
	      __set_errno (EINVAL);
	      return -1;
	    }
	  right_prec = to_digit (*fmt);

	  while (isdigit (*++fmt))
	    {
	      right_prec *= 10;
	      right_prec += to_digit (*fmt);
	    }
	}

      /* Handle modifier.  This is an extension.  */
      if (*fmt == 'L')
	{
	  ++fmt;
	  if (!__ldbl_is_dbl)
	    is_long_double = 1;
	}

      /* Handle format specifier.  */
      char int_symbol[4];
      switch (*fmt++)
	{
	case 'i': {		/* Use international currency symbol.  */
	  const char *int_curr_symbol;

	  int_curr_symbol = _NL_CURRENT (LC_MONETARY, INT_CURR_SYMBOL);
	  strncpy(int_symbol, int_curr_symbol, 3);
	  int_symbol[3] = '\0';

	  currency_symbol_len = 3;
	  currency_symbol = &int_symbol[0];
	  space_char = int_curr_symbol[3];
	  int_format = 1;
	  break;
	}
	case 'n':		/* Use national currency symbol.  */
	  currency_symbol = _NL_CURRENT (LC_MONETARY, CURRENCY_SYMBOL);
	  currency_symbol_len = strlen (currency_symbol);
	  space_char = ' ';
	  int_format = 0;
	  break;
	default:		/* Any unrecognized format is an error.  */
	  __set_errno (EINVAL);
	  return -1;
	}

      /* If not specified by the format string now find the values for
	 the format specification.  */
      if (p_sign_posn == -2)
	p_sign_posn = *_NL_CURRENT (LC_MONETARY, int_format ? INT_P_SIGN_POSN : P_SIGN_POSN);
      if (n_sign_posn == -2)
	n_sign_posn = *_NL_CURRENT (LC_MONETARY, int_format ? INT_N_SIGN_POSN : N_SIGN_POSN);

      if (right_prec == -1)
	{
	  right_prec = *_NL_CURRENT (LC_MONETARY, int_format ? INT_FRAC_DIGITS : FRAC_DIGITS);

	  if (right_prec == '\377')
	    right_prec = 2;
	}

      /* If we have to print the digits grouped determine how many
	 extra characters this means.  */
      if (group && left_prec != -1)
	left_prec += __guess_grouping (left_prec,
				       _NL_CURRENT (LC_MONETARY, MON_GROUPING));

      /* Now it's time to get the value.  */
      if (is_long_double == 1)
	{
	  fpnum.ldbl = va_arg (ap, long double);
	  is_negative = fpnum.ldbl < 0;
	  if (is_negative)
	    fpnum.ldbl = -fpnum.ldbl;
	}
      else
	{
	  fpnum.dbl = va_arg (ap, double);
	  is_negative = fpnum.dbl < 0;
	  if (is_negative)
	    fpnum.dbl = -fpnum.dbl;
	}

      /* We now know the sign of the value and can determine the format.  */
      if (is_negative)
	{
	  sign_string = _NL_CURRENT (LC_MONETARY, NEGATIVE_SIGN);
	  /* If the locale does not specify a character for the
	     negative sign we use a '-'.  */
	  if (*sign_string == '\0')
	    sign_string = (const char *) "-";
	  cs_precedes = *_NL_CURRENT (LC_MONETARY, int_format ? INT_N_CS_PRECEDES : N_CS_PRECEDES);
	  sep_by_space = *_NL_CURRENT (LC_MONETARY, int_format ? INT_N_SEP_BY_SPACE : N_SEP_BY_SPACE);
	  sign_posn = n_sign_posn;

	  other_sign_string = _NL_CURRENT (LC_MONETARY, POSITIVE_SIGN);
	  other_cs_precedes = *_NL_CURRENT (LC_MONETARY, int_format ? INT_P_CS_PRECEDES : P_CS_PRECEDES);
	  other_sep_by_space = *_NL_CURRENT (LC_MONETARY, int_format ? INT_P_SEP_BY_SPACE : P_SEP_BY_SPACE);
	  other_sign_posn = p_sign_posn;
	}
      else
	{
	  sign_string = _NL_CURRENT (LC_MONETARY, POSITIVE_SIGN);
	  cs_precedes = *_NL_CURRENT (LC_MONETARY, int_format ? INT_P_CS_PRECEDES : P_CS_PRECEDES);
	  sep_by_space = *_NL_CURRENT (LC_MONETARY, int_format ? INT_P_SEP_BY_SPACE : P_SEP_BY_SPACE);
	  sign_posn = p_sign_posn;

	  other_sign_string = _NL_CURRENT (LC_MONETARY, NEGATIVE_SIGN);
	  if (*other_sign_string == '\0')
	    other_sign_string = (const char *) "-";
	  other_cs_precedes = *_NL_CURRENT (LC_MONETARY, int_format ? INT_N_CS_PRECEDES : N_CS_PRECEDES);
	  other_sep_by_space = *_NL_CURRENT (LC_MONETARY, int_format ? INT_N_SEP_BY_SPACE : N_SEP_BY_SPACE);
	  other_sign_posn = n_sign_posn;
	}

      /* Set default values for unspecified information.  */
      if (cs_precedes != 0)
	cs_precedes = 1;
      if (other_cs_precedes != 0)
	other_cs_precedes = 1;
      if (sep_by_space == '\377')
	sep_by_space = 0;
      if (other_sep_by_space == '\377')
	other_sep_by_space = 0;
      if (sign_posn == '\377')
	sign_posn = 1;
      if (other_sign_posn == '\377')
	other_sign_posn = 1;

      /* Check for degenerate cases */
      if (sep_by_space == 2)
	{
	  if (sign_posn == 0 ||
	      (sign_posn == 1 && !cs_precedes) ||
	      (sign_posn == 2 && cs_precedes))
	    /* sign and symbol are not adjacent, so no separator */
	    sep_by_space = 0;
	}
      if (other_sep_by_space == 2)
	{
	  if (other_sign_posn == 0 ||
	      (other_sign_posn == 1 && !other_cs_precedes) ||
	      (other_sign_posn == 2 && other_cs_precedes))
	    /* sign and symbol are not adjacent, so no separator */
	    other_sep_by_space = 0;
	}

      /* Set the left precision and padding needed for alignment */
      if (left_prec == -1)
	{
	  left_prec = 0;
	  left_pad = 0;
	}
      else
	{
	  /* Set left_pad to number of spaces needed to align positive
	     and negative formats */

	  int left_bytes = 0;
	  int other_left_bytes = 0;

	  /* Work out number of bytes for currency string and separator
	     preceding the value */
	  if (cs_precedes)
	    {
	      left_bytes += currency_symbol_len;
	      if (sep_by_space != 0)
		++left_bytes;
	    }

	  if (other_cs_precedes)
	    {
	      other_left_bytes += currency_symbol_len;
	      if (other_sep_by_space != 0)
		++other_left_bytes;
	    }

	  /* Work out number of bytes for the sign (or left parenthesis)
	     preceding the value */
	  if (sign_posn == 0 && is_negative)
	    ++left_bytes;
	  else if (sign_posn == 1)
	    left_bytes += strlen (sign_string);
	  else if (cs_precedes && (sign_posn == 3 || sign_posn == 4))
	    left_bytes += strlen (sign_string);

	  if (other_sign_posn == 0 && !is_negative)
	    ++other_left_bytes;
	  else if (other_sign_posn == 1)
	    other_left_bytes += strlen (other_sign_string);
	  else if (other_cs_precedes &&
		   (other_sign_posn == 3 || other_sign_posn == 4))
	    other_left_bytes += strlen (other_sign_string);

	  /* Compare the number of bytes preceding the value for
	     each format, and set the padding accordingly */
	  if (other_left_bytes > left_bytes)
	    left_pad = other_left_bytes - left_bytes;
	  else
	    left_pad = 0;
	}

      /* Perhaps we'll someday make these things configurable so
	 better start using symbolic names now.  */
#define left_paren '('
#define right_paren ')'

      startp = dest;		/* Remember start so we can compute length.  */

      while (left_pad-- > 0)
	out_char (' ');

      if (sign_posn == 0 && is_negative)
	out_char (left_paren);

      if (cs_precedes)
	{
	  if (sign_posn != 0 && sign_posn != 2 && sign_posn != 4
	      && sign_posn != 5)
	    {
	      out_string (sign_string);
	      if (sep_by_space == 2)
		out_char (' ');
	    }

	  if (print_curr_symbol)
	    out_string (currency_symbol);

	  if (sign_posn == 4)
	    {
	      if (print_curr_symbol && sep_by_space == 2)
		out_char (space_char);
	      out_string (sign_string);
	      if (sep_by_space == 1)
		/* POSIX.2 and SUS are not clear on this case, but C99
		   says a space follows the adjacent-symbol-and-sign */
		out_char (' ');
	    }
	  else
	    if (print_curr_symbol && sep_by_space == 1)
	      out_char (space_char);
	}
      else
	if (sign_posn != 0 && sign_posn != 2 && sign_posn != 3
	    && sign_posn != 4 && sign_posn != 5)
	  out_string (sign_string);

      /* Print the number.  */
#ifdef _IO_MTSAFE_IO
      f._sbf._f._lock = NULL;
#endif
      _IO_init_internal (&f._sbf._f, 0);
      _IO_JUMPS (&f._sbf) = &_IO_str_jumps;
      _IO_str_init_static_internal (&f, dest, (s + maxsize) - dest, dest);
      /* We clear the last available byte so we can find out whether
	 the numeric representation is too long.  */
      s[maxsize - 1] = '\0';

      memset (&info, '\0', sizeof (info));
      info.prec = right_prec;
      info.width = left_prec + (right_prec ? (right_prec + 1) : 0);
      info.spec = 'f';
      info.is_long_double = is_long_double;
      info.group = group;
      info.pad = pad;
      info.extra = 1;		/* This means use values from LC_MONETARY.  */

      ptr = &fpnum;
      done = __printf_fp_l (&f._sbf._f, loc, &info, &ptr);
      if (done < 0)
	return -1;

      if (s[maxsize - 1] != '\0')
	{
	  __set_errno (E2BIG);
	  return -1;
	}

      dest += done;

      if (!cs_precedes)
	{
	  if (sign_posn == 3)
	    {
	      if (sep_by_space == 1)
		out_char (' ');
	      out_string (sign_string);
	    }

	  if (print_curr_symbol)
	    {
	      if ((sign_posn == 3 && sep_by_space == 2)
		  || (sign_posn == 4 && sep_by_space == 1)
		  || (sign_posn == 2 && sep_by_space == 1)
		  || (sign_posn == 1 && sep_by_space == 1)
		  || (sign_posn == 0 && sep_by_space == 1))
		out_char (space_char);
	      out_nstring (currency_symbol, currency_symbol_len);
	    }

	  if (sign_posn == 4)
	    {
	      if (sep_by_space == 2)
		out_char (' ');
	      out_string (sign_string);
	    }
	}

      if (sign_posn == 2)
	{
	  if (sep_by_space == 2)
	    out_char (' ');
	  out_string (sign_string);
	}

      if (sign_posn == 0 && is_negative)
	out_char (right_paren);

      /* Now test whether the output width is filled.  */
      if (dest - startp < width)
	{
	  if (left)
	    /* We simply have to fill using spaces.  */
	    do
	      out_char (' ');
	    while (dest - startp < width);
	  else
	    {
	      long int dist = width - (dest - startp);
	      for (char *cp = dest - 1; cp >= startp; --cp)
		cp[dist] = cp[0];

	      dest += dist;

	      do
		startp[--dist] = ' ';
	      while (dist > 0);
	    }
	}
    }

  /* Terminate the string.  */
  *dest = '\0';

  return dest - s;
}

ssize_t
___strfmon_l (char *s, size_t maxsize, locale_t loc, const char *format, ...)
{
  va_list ap;

  va_start (ap, format);

  ssize_t res = __vstrfmon_l (s, maxsize, loc, format, ap);

  va_end (ap);

  return res;
}
ldbl_strong_alias (___strfmon_l, __strfmon_l)
ldbl_weak_alias (___strfmon_l, strfmon_l)