glibc/stdio-common/vfprintf-process-arg.c

/* Argument-processing fragment for vfprintf.
   Copyright (C) 1991-2023 Free Software Foundation, Inc.
   This file is part of the GNU C Library.

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

/* This file is included twice from vfprintf-internal.c, for standard
   and GNU-style positional (%N$) arguments.  Before that,
   process_arg_int etc. macros have to be defined to extract one
   argument of the appropriate type, in addition to the file-specific
   macros in vfprintf-internal.c.  */

{
  /* Start real work.  We know about all flags and modifiers and
     now process the wanted format specifier.  */
LABEL (form_percent):
  /* Write a literal "%".  */
  Xprintf_buffer_putc (buf, L_('%'));
  break;

LABEL (form_integer):
  /* Signed decimal integer.  */
  base = 10;

  if (is_longlong)
    {
      long long int signed_number = process_arg_long_long_int ();
      is_negative = signed_number < 0;
      number.longlong = is_negative ? (- signed_number) : signed_number;

      goto LABEL (longlong_number);
    }
  else
    {
      long int signed_number;
      if (is_long_num)
        signed_number = process_arg_long_int ();
      else if (is_char)
        signed_number = (signed char) process_arg_unsigned_int ();
      else if (!is_short)
        signed_number = process_arg_int ();
      else
        signed_number = (short int) process_arg_unsigned_int ();

      is_negative = signed_number < 0;
      number.word = is_negative ? (- signed_number) : signed_number;

      goto LABEL (number);
    }
  /* NOTREACHED */

LABEL (form_unsigned):
  /* Unsigned decimal integer.  */
  base = 10;
  goto LABEL (unsigned_number);
  /* NOTREACHED */

LABEL (form_octal):
  /* Unsigned octal integer.  */
  base = 8;
  goto LABEL (unsigned_number);
  /* NOTREACHED */

LABEL (form_hexa):
  /* Unsigned hexadecimal integer.  */
  base = 16;
  goto LABEL (unsigned_number);
  /* NOTREACHED */

LABEL (form_binary):
  /* Unsigned binary integer.  */
  base = 2;
  goto LABEL (unsigned_number);
  /* NOTREACHED */

LABEL (unsigned_number):      /* Unsigned number of base BASE.  */

  /* ISO specifies the `+' and ` ' flags only for signed
     conversions.  */
  is_negative = 0;
  showsign = 0;
  space = 0;

  if (is_longlong)
    {
      number.longlong = process_arg_unsigned_long_long_int ();

      LABEL (longlong_number):
      if (prec < 0)
        /* Supply a default precision if none was given.  */
        prec = 1;
      else
        /* We have to take care for the '0' flag.  If a precision
           is given it must be ignored.  */
        pad = L_(' ');

      /* If the precision is 0 and the number is 0 nothing has to
         be written for the number, except for the 'o' format in
         alternate form.  */
      if (prec == 0 && number.longlong == 0)
        {
          string = workend;
          if (base == 8 && alt)
            *--string = L_('0');
        }
      else
        /* Put the number in WORK.  */
        string = _itoa (number.longlong, workend, base, spec == L_('X'));
      /* Simplify further test for num != 0.  */
      number.word = number.longlong != 0;
    }
  else
    {
      if (is_long_num)
        number.word = process_arg_unsigned_long_int ();
      else if (is_char)
        number.word = (unsigned char) process_arg_unsigned_int ();
      else if (!is_short)
        number.word = process_arg_unsigned_int ();
      else
        number.word = (unsigned short int) process_arg_unsigned_int ();

      LABEL (number):
      if (prec < 0)
        /* Supply a default precision if none was given.  */
        prec = 1;
      else
        /* We have to take care for the '0' flag.  If a precision
           is given it must be ignored.  */
        pad = L_(' ');

      /* If the precision is 0 and the number is 0 nothing has to
         be written for the number, except for the 'o' format in
         alternate form.  */
      if (prec == 0 && number.word == 0)
        {
          string = workend;
          if (base == 8 && alt)
            *--string = L_('0');
        }
      else
        /* Put the number in WORK.  */
        string = _itoa_word (number.word, workend, base,
                             spec == L_('X'));
    }

  /* Grouping is also used for outdigits translation.  */
  struct grouping_iterator iter;
  bool number_slow_path = group || (use_outdigits && base == 10);
  if (group)
    __grouping_iterator_init (&iter, LC_NUMERIC, _NL_CURRENT_LOCALE,
                              workend - string);
  else if (use_outdigits && base == 10)
    __grouping_iterator_init_none (&iter, workend - string);

  int number_length;
#ifndef COMPILE_WPRINTF
  if (use_outdigits && base == 10)
    number_length = __translated_number_width (_NL_CURRENT_LOCALE,
                                               string, workend);
  else
    number_length = workend - string;
  if (group)
    number_length += iter.separators * strlen (thousands_sep);
#else
  number_length = workend - string;
  /* All wide separators have length 1.  */
  if (group && thousands_sep != L'\0')
    number_length += iter.separators;
#endif

  /* The marker comes right before the number, but is not subject
     to grouping.  */
  bool octal_marker = (prec <= number_length && number.word != 0
                       && alt && base == 8);

  prec = MAX (0, prec - (workend - string));

  if (!left)
    {
      width -= number_length + prec;

      if (number.word != 0 && alt && (base == 16 || base == 2))
        /* Account for 0X, 0x, 0B or 0b hex or binary marker.  */
        width -= 2;

      if (octal_marker)
        --width;

      if (is_negative || showsign || space)
        --width;

      if (pad == L_(' '))
        {
          Xprintf_buffer_pad (buf, L_(' '), width);
          width = 0;
        }

      if (is_negative)
        Xprintf_buffer_putc (buf, L_('-'));
      else if (showsign)
        Xprintf_buffer_putc (buf, L_('+'));
      else if (space)
        Xprintf_buffer_putc (buf, L_(' '));

      if (number.word != 0 && alt && (base == 16 || base == 2))
        {
          Xprintf_buffer_putc (buf, L_('0'));
          Xprintf_buffer_putc (buf, spec);
        }

      width += prec;
      Xprintf_buffer_pad (buf, L_('0'), width);

      if (octal_marker)
        Xprintf_buffer_putc (buf, L_('0'));

      if (number_slow_path)
        group_number (buf, &iter, string, workend, thousands_sep,
                      use_outdigits && base == 10);
      else
        Xprintf_buffer_write (buf, string, workend - string);

      break;
    }
  else
    {
      if (is_negative)
        {
          Xprintf_buffer_putc (buf, L_('-'));
          --width;
        }
      else if (showsign)
        {
          Xprintf_buffer_putc (buf, L_('+'));
          --width;
        }
      else if (space)
        {
          Xprintf_buffer_putc (buf, L_(' '));
          --width;
        }

      if (number.word != 0 && alt && (base == 16 || base == 2))
        {
          Xprintf_buffer_putc (buf, L_('0'));
          Xprintf_buffer_putc (buf, spec);
          width -= 2;
        }

      if (octal_marker)
	--width;

      width -= workend - string + prec;

      Xprintf_buffer_pad (buf, L_('0'), prec);

      if (octal_marker)
        Xprintf_buffer_putc (buf, L_('0'));

      if (number_slow_path)
        group_number (buf, &iter, string, workend, thousands_sep,
                      use_outdigits && base == 10);
      else
        Xprintf_buffer_write (buf, string, workend - string);

      Xprintf_buffer_pad (buf, L_(' '), width);
      break;
    }

LABEL (form_pointer):
  /* Generic pointer.  */
  {
    const void *ptr = process_arg_pointer ();
    if (ptr != NULL)
      {
        /* If the pointer is not NULL, write it as a %#x spec.  */
        base = 16;
        number.word = (unsigned long int) ptr;
        is_negative = 0;
        alt = 1;
        group = 0;
        spec = L_('x');
        goto LABEL (number);
      }
    else
      {
        /* Write "(nil)" for a nil pointer.  */
        string = (CHAR_T *) L_("(nil)");
        /* Make sure the full string "(nil)" is printed.  */
        if (prec < 5)
          prec = 5;
        /* This is a wide string iff compiling wprintf.  */
        is_long = sizeof (CHAR_T) > 1;
        goto LABEL (print_string);
      }
  }
  /* NOTREACHED */

LABEL (form_number):
  if ((mode_flags & PRINTF_FORTIFY) != 0)
    {
      if (! readonly_format)
        {
          extern int __readonly_area (const void *, size_t)
            attribute_hidden;
          readonly_format
            = __readonly_area (format, ((STR_LEN (format) + 1)
                                        * sizeof (CHAR_T)));
        }
      if (readonly_format < 0)
        __libc_fatal ("*** %n in writable segment detected ***\n");
    }
  /* Answer the count of characters written.  */
  void *ptrptr = process_arg_pointer ();
  unsigned int written = Xprintf_buffer_done (buf);
  if (is_longlong)
    *(long long int *) ptrptr = written;
  else if (is_long_num)
    *(long int *) ptrptr = written;
  else if (is_char)
    *(char *) ptrptr = written;
  else if (!is_short)
    *(int *) ptrptr = written;
  else
    *(short int *) ptrptr = written;
  break;

LABEL (form_strerror):
  /* Print description of error ERRNO.  */
  if (alt)
    string = (CHAR_T *) __get_errname (save_errno);
  else
    string = (CHAR_T *) __strerror_r (save_errno, (char *) work_buffer,
                                      WORK_BUFFER_SIZE * sizeof (CHAR_T));
  if (string == NULL)
    {
      /* Print as a decimal number. */
      base = 10;
      is_negative = save_errno < 0;
      number.word = save_errno;
      if (is_negative)
        number.word = -number.word;
      goto LABEL (number);
    }
  else
    {
      is_long = 0;  /* This is no wide-char string.  */
      goto LABEL (print_string);
    }

LABEL (form_character):
  /* Character.  */
  if (is_long)
    goto LABEL (form_wcharacter);
  --width;  /* Account for the character itself.  */
  if (!left)
    Xprintf_buffer_pad (buf, L_(' '), width);
#ifdef COMPILE_WPRINTF
  __wprintf_buffer_putc (buf, __btowc ((unsigned char) /* Promoted. */
                                       process_arg_int ()));
#else
  __printf_buffer_putc (buf, (unsigned char) /* Promoted.  */
                        process_arg_int ());
#endif
  if (left)
    Xprintf_buffer_pad (buf, L_(' '), width);
  break;

LABEL (form_string):
  {
    size_t len;

    /* The string argument could in fact be `char *' or `wchar_t *'.
       But this should not make a difference here.  */
#ifdef COMPILE_WPRINTF
    string = (CHAR_T *) process_arg_wstring ();
#else
    string = (CHAR_T *) process_arg_string ();
#endif
    /* Entry point for printing other strings.  */
    LABEL (print_string):

    if (string == NULL)
      {
        /* Write "(null)" if there's space.  */
        if (prec == -1 || prec >= (int) array_length (null) - 1)
          {
            string = (CHAR_T *) null;
            len = array_length (null) - 1;
          }
        else
          {
            string = (CHAR_T *) L"";
            len = 0;
          }
      }
    else if (!is_long && spec != L_('S'))
      {
#ifdef COMPILE_WPRINTF
        outstring_converted_wide_string (buf, (const char *) string,
                                         prec, width, left);
        /* The padding has already been written.  */
        break;
#else
        if (prec != -1)
          /* Search for the end of the string, but don't search past
             the length (in bytes) specified by the precision.  */
          len = __strnlen (string, prec);
        else
          len = strlen (string);
#endif
      }
    else
      {
#ifdef COMPILE_WPRINTF
        if (prec != -1)
          /* Search for the end of the string, but don't search past
             the length specified by the precision.  */
          len = __wcsnlen (string, prec);
        else
          len = __wcslen (string);
#else
        outstring_converted_wide_string (buf, (const wchar_t *) string,
                                         prec, width, left);
        /* The padding has already been written.  */
        break;
#endif
      }

    if ((width -= len) < 0)
      {
        Xprintf_buffer_write (buf, string, len);
        break;
      }

    if (!left)
      Xprintf_buffer_pad (buf, L_(' '), width);
    Xprintf_buffer_write (buf, string, len);
    if (left)
      Xprintf_buffer_pad (buf, L_(' '), width);
  }
  break;

#ifdef COMPILE_WPRINTF
LABEL (form_wcharacter):
  {
    /* Wide character.  */
    --width;
    if (!left)
      Xprintf_buffer_pad (buf, L_(' '), width);
    Xprintf_buffer_putc (buf, process_arg_wchar_t ());
    if (left)
      Xprintf_buffer_pad (buf, L_(' '), width);
  }
  break;

#else /* !COMPILE_WPRINTF */
LABEL (form_wcharacter):
  {
    /* Wide character.  */
    char wcbuf[MB_LEN_MAX];
    mbstate_t mbstate;
    size_t len;

    memset (&mbstate, '\0', sizeof (mbstate_t));
    len = __wcrtomb (wcbuf, process_arg_wchar_t (), &mbstate);
    if (len == (size_t) -1)
      {
        /* Something went wrong during the conversion.  Bail out.  */
        __printf_buffer_mark_failed (buf);
        goto all_done;
      }
    width -= len;
    if (!left)
      Xprintf_buffer_pad (buf, L_(' '), width);
    Xprintf_buffer_write (buf, wcbuf, len);
    if (left)
      Xprintf_buffer_pad (buf, L_(' '), width);
  }
  break;
#endif /* !COMPILE_WPRINTF */
}