trio.c

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#if TRIO_EXTENSION
/*************************************************************************
 * TrioFindNamespace
 *
 * Find registered user-defined specifier.
 * The prev argument is used for optimization only.
 */
TRIO_PRIVATE trio_userdef_t *
TrioFindNamespace
TRIO_ARGS2((name, prev),
	   TRIO_CONST char *name,
	   trio_userdef_t **prev)
{
  trio_userdef_t *def;
  
  if (internalEnterCriticalRegion)
    (void)internalEnterCriticalRegion(NULL);
  
  for (def = internalUserDef; def; def = def->next)
    {
      /* Case-sensitive string comparison */
      if (trio_equal_case(def->name, name))
	break;
      
      if (prev)
	*prev = def;
    }
  
  if (internalLeaveCriticalRegion)
    (void)internalLeaveCriticalRegion(NULL);
  
  return def;
}
#endif

/*************************************************************************
 * TrioPower
 *
 * Description:
 *  Calculate pow(base, exponent), where number and exponent are integers.
 */
TRIO_PRIVATE trio_long_double_t
TrioPower
TRIO_ARGS2((number, exponent),
	   int number,
	   int exponent)
{
  trio_long_double_t result;

  if (number == 10)
    {
      switch (exponent)
	{
	  /* Speed up calculation of common cases */
	case 0:
	  result = (trio_long_double_t)number * TRIO_SUFFIX_LONG(1E-1);
	  break;
	case 1:
	  result = (trio_long_double_t)number * TRIO_SUFFIX_LONG(1E+0);
	  break;
	case 2:
	  result = (trio_long_double_t)number * TRIO_SUFFIX_LONG(1E+1);
	  break;
	case 3:
	  result = (trio_long_double_t)number * TRIO_SUFFIX_LONG(1E+2);
	  break;
	case 4:
	  result = (trio_long_double_t)number * TRIO_SUFFIX_LONG(1E+3);
	  break;
	case 5:
	  result = (trio_long_double_t)number * TRIO_SUFFIX_LONG(1E+4);
	  break;
	case 6:
	  result = (trio_long_double_t)number * TRIO_SUFFIX_LONG(1E+5);
	  break;
	case 7:
	  result = (trio_long_double_t)number * TRIO_SUFFIX_LONG(1E+6);
	  break;
	case 8:
	  result = (trio_long_double_t)number * TRIO_SUFFIX_LONG(1E+7);
	  break;
	case 9:
	  result = (trio_long_double_t)number * TRIO_SUFFIX_LONG(1E+8);
	  break;
	default:
	  result = powl((trio_long_double_t)number,
			(trio_long_double_t)exponent);
	  break;
	}
    }
  else
    {
      return powl((trio_long_double_t)number, (trio_long_double_t)exponent);
    }
  return result;
}

/*************************************************************************
 * TrioLogarithm
 */
TRIO_PRIVATE double
TrioLogarithm
TRIO_ARGS2((number, base),
	   double number,
	   int base)
{
  double result;

  if (number <= 0.0)
    {
      /* xlC crashes on log(0) */
      result = (number == 0.0) ? trio_ninf() : trio_nan();
    }
  else
    {
      if (base == 10)
	{
	  result = log10(number);
	}
      else
	{
	  result = log10(number) / log10((double)base);
	}
    }
  return result;
}

/*************************************************************************
 * TrioLogarithmBase
 */
TRIO_PRIVATE double
TrioLogarithmBase
TRIO_ARGS1((base),
	   int base)
{
  switch (base)
    {
    case BASE_BINARY : return 1.0;
    case BASE_OCTAL  : return 3.0;
    case BASE_DECIMAL: return 3.321928094887362345;
    case BASE_HEX    : return 4.0;
    default          : return TrioLogarithm((double)base, 2);
    }
}

/*************************************************************************
 * TrioParse
 *
 * Description:
 *  Parse the format string
 */
TRIO_PRIVATE int
TrioParse
TRIO_ARGS5((type, format, parameters, arglist, argarray),
	   int type,
	   TRIO_CONST char *format,
	   trio_parameter_t *parameters,
	   va_list *arglist,
	   trio_pointer_t *argarray)
{
  /* Count the number of times a parameter is referenced */
  unsigned short usedEntries[MAX_PARAMETERS];
  /* Parameter counters */
  int parameterPosition;
  int currentParam;
  int maxParam = -1;
  /* Utility variables */
  trio_flags_t flags;
  int width;
  int precision;
  int varsize;
  int base;
  int index;  /* Index into formatting string */
  int dots;  /* Count number of dots in modifier part */
  BOOLEAN_T positional;  /* Does the specifier have a positional? */
  BOOLEAN_T gotSticky = FALSE;  /* Are there any sticky modifiers at all? */
  /*
   * indices specifies the order in which the parameters must be
   * read from the va_args (this is necessary to handle positionals)
   */
  int indices[MAX_PARAMETERS];
  int pos = 0;
  /* Various variables */
  char ch;
#if defined(TRIO_COMPILER_SUPPORTS_MULTIBYTE)
  int charlen;
#endif
  int save_errno;
  int i = -1;
  int num;
  char *tmpformat;

  /* One and only one of arglist and argarray must be used */
  assert((arglist != NULL) ^ (argarray != NULL));
  
  /*
   * The 'parameters' array is not initialized, but we need to
   * know which entries we have used.
   */
  memset(usedEntries, 0, sizeof(usedEntries));

  save_errno = errno;
  index = 0;
  parameterPosition = 0;
#if defined(TRIO_COMPILER_SUPPORTS_MULTIBYTE)
  (void)mblen(NULL, 0);
#endif
  
  while (format[index])
    {
#if defined(TRIO_COMPILER_SUPPORTS_MULTIBYTE)
      if (! isascii(format[index]))
	{
	  /*
	   * Multibyte characters cannot be legal specifiers or
	   * modifiers, so we skip over them.
	   */
	  charlen = mblen(&format[index], MB_LEN_MAX);
	  index += (charlen > 0) ? charlen : 1;
	  continue; /* while */
	}
#endif /* TRIO_COMPILER_SUPPORTS_MULTIBYTE */
      if (CHAR_IDENTIFIER == format[index++])
	{
	  if (CHAR_IDENTIFIER == format[index])
	    {
	      index++;
	      continue; /* while */
	    }

	  flags = FLAGS_NEW;
	  dots = 0;
	  currentParam = TrioGetPosition(format, &index);
	  positional = (NO_POSITION != currentParam);
	  if (!positional)
	    {
	      /* We have no positional, get the next counter */
	      currentParam = parameterPosition;
	    }
          if(currentParam >= MAX_PARAMETERS)
	    {
	      /* Bail out completely to make the error more obvious */
	      return TRIO_ERROR_RETURN(TRIO_ETOOMANY, index);
	    }

	  if (currentParam > maxParam)
	    maxParam = currentParam;

	  /* Default values */
	  width = NO_WIDTH;
	  precision = NO_PRECISION;
	  base = NO_BASE;
	  varsize = NO_SIZE;

	  while (TrioIsQualifier(format[index]))
	    {
	      ch = format[index++];

	      switch (ch)
		{
		case QUALIFIER_SPACE:
		  flags |= FLAGS_SPACE;
		  break;

		case QUALIFIER_PLUS:
		  flags |= FLAGS_SHOWSIGN;
		  break;

		case QUALIFIER_MINUS:
		  flags |= FLAGS_LEFTADJUST;
		  flags &= ~FLAGS_NILPADDING;
		  break;

		case QUALIFIER_ALTERNATIVE:
		  flags |= FLAGS_ALTERNATIVE;
		  break;

		case QUALIFIER_DOT:
		  if (dots == 0) /* Precision */
		    {
		      dots++;

		      /* Skip if no precision */
		      if (QUALIFIER_DOT == format[index])
			break;
		      
		      /* After the first dot we have the precision */
		      flags |= FLAGS_PRECISION;
		      if ((QUALIFIER_STAR == format[index])
#if defined(QUALIFIER_PARAM)
			  || (QUALIFIER_PARAM == format[index])
#endif
			  )
			{
			  index++;
			  flags |= FLAGS_PRECISION_PARAMETER;

			  precision = TrioGetPosition(format, &index);
			  if (precision == NO_POSITION)
			    {
			      parameterPosition++;
			      if (positional)
				precision = parameterPosition;
			      else
				{
				  precision = currentParam;
				  currentParam = precision + 1;
				}
			    }
			  else
			    {
			      if (! positional)
				currentParam = precision + 1;
			      if (width > maxParam)
				maxParam = precision;
			    }
			  if (currentParam > maxParam)
			    maxParam = currentParam;
			}
		      else
			{
			  precision = trio_to_long(&format[index],
						   &tmpformat,
						   BASE_DECIMAL);
			  index = (int)(tmpformat - format);
			}
		    }
		  else if (dots == 1) /* Base */
		    {
		      dots++;
		      
		      /* After the second dot we have the base */
		      flags |= FLAGS_BASE;
		      if ((QUALIFIER_STAR == format[index])
#if defined(QUALIFIER_PARAM)
			  || (QUALIFIER_PARAM == format[index])
#endif
			  )
			{
			  index++;
			  flags |= FLAGS_BASE_PARAMETER;
			  base = TrioGetPosition(format, &index);
			  if (base == NO_POSITION)
			    {
			      parameterPosition++;
			      if (positional)
				base = parameterPosition;
			      else
				{
				  base = currentParam;
				  currentParam = base + 1;
				}
			    }
			  else
			    {
			      if (! positional)
				currentParam = base + 1;
			      if (base > maxParam)
				maxParam = base;
			    }
			  if (currentParam > maxParam)
			    maxParam = currentParam;
			}
		      else
			{
			  base = trio_to_long(&format[index],
					      &tmpformat,
					      BASE_DECIMAL);
			  if (base > MAX_BASE)
			    return TRIO_ERROR_RETURN(TRIO_EINVAL, index);
			  index = (int)(tmpformat - format);
			}
		    }
		  else
		    {
		      return TRIO_ERROR_RETURN(TRIO_EINVAL, index);
		    }
		  break; /* QUALIFIER_DOT */

#if defined(QUALIFIER_PARAM)
		case QUALIFIER_PARAM:
		  type = TYPE_PRINT;
		  /* FALLTHROUGH */
#endif
		case QUALIFIER_STAR:
		  /* This has different meanings for print and scan */
		  if (TYPE_PRINT == type)
		    {
		      /* Read with from parameter */
		      flags |= (FLAGS_WIDTH | FLAGS_WIDTH_PARAMETER);
		      width = TrioGetPosition(format, &index);
		      if (width == NO_POSITION)
			{
			  parameterPosition++;
			  if (positional)
			    width = parameterPosition;
			  else
			    {
			      width = currentParam;
			      currentParam = width + 1;
			    }
			}
		      else
			{
			  if (! positional)
			    currentParam = width + 1;
			  if (width > maxParam)
			    maxParam = width;
			}
		      if (currentParam > maxParam)
			maxParam = currentParam;
		    }
		  else
		    {
		      /* Scan, but do not store result */
		      flags |= FLAGS_IGNORE;
		    }

		  break; /* QUALIFIER_STAR */

		case '0':
		  if (! (flags & FLAGS_LEFTADJUST))
		    flags |= FLAGS_NILPADDING;
		  /* FALLTHROUGH */
		case '1': case '2': case '3': case '4':
		case '5': case '6': case '7': case '8': case '9':
		  flags |= FLAGS_WIDTH;
		  /* &format[index - 1] is used to "rewind" the read
		   * character from format
		   */
		  width = trio_to_long(&format[index - 1],
				       &tmpformat,
				       BASE_DECIMAL);
		  index = (int)(tmpformat - format);
		  break;

		case QUALIFIER_SHORT:
		  if (flags & FLAGS_SHORTSHORT)
		    return TRIO_ERROR_RETURN(TRIO_EINVAL, index);
		  else if (flags & FLAGS_SHORT)
		    flags |= FLAGS_SHORTSHORT;
		  else
		    flags |= FLAGS_SHORT;
		  break;

		case QUALIFIER_LONG:
		  if (flags & FLAGS_QUAD)
		    return TRIO_ERROR_RETURN(TRIO_EINVAL, index);
		  else if (flags & FLAGS_LONG)
		    flags |= FLAGS_QUAD;
		  else
		    flags |= FLAGS_LONG;
		  break;

		case QUALIFIER_LONG_UPPER:
		  flags |= FLAGS_LONGDOUBLE;
		  break;

#if defined(QUALIFIER_SIZE_T)
		case QUALIFIER_SIZE_T:
		  flags |= FLAGS_SIZE_T;
		  /* Modify flags for later truncation of number */
		  if (sizeof(size_t) == sizeof(trio_ulonglong_t))
		    flags |= FLAGS_QUAD;
		  else if (sizeof(size_t) == sizeof(long))
		    flags |= FLAGS_LONG;
		  break;
#endif

#if defined(QUALIFIER_PTRDIFF_T)
		case QUALIFIER_PTRDIFF_T:
		  flags |= FLAGS_PTRDIFF_T;
		  if (sizeof(ptrdiff_t) == sizeof(trio_ulonglong_t))
		    flags |= FLAGS_QUAD;
		  else if (sizeof(ptrdiff_t) == sizeof(long))
		    flags |= FLAGS_LONG;
		  break;
#endif

#if defined(QUALIFIER_INTMAX_T)
		case QUALIFIER_INTMAX_T:
		  flags |= FLAGS_INTMAX_T;
		  if (sizeof(trio_intmax_t) == sizeof(trio_ulonglong_t))
		    flags |= FLAGS_QUAD;
		  else if (sizeof(trio_intmax_t) == sizeof(long))
		    flags |= FLAGS_LONG;
		  break;
#endif

#if defined(QUALIFIER_QUAD)
		case QUALIFIER_QUAD:
		  flags |= FLAGS_QUAD;
		  break;
#endif

#if defined(QUALIFIER_FIXED_SIZE)
		case QUALIFIER_FIXED_SIZE: