trio.c

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		  if (flags & FLAGS_FIXED_SIZE)
		    return TRIO_ERROR_RETURN(TRIO_EINVAL, index);

		  if (flags & (FLAGS_ALL_SIZES | FLAGS_LONGDOUBLE |
			       FLAGS_WIDECHAR | FLAGS_VARSIZE_PARAMETER))
		    return TRIO_ERROR_RETURN(TRIO_EINVAL, index);

		  if ((format[index] == '6') &&
		      (format[index + 1] == '4'))
		    {
		      varsize = sizeof(trio_int64_t);
		      index += 2;
		    }
		  else if ((format[index] == '3') &&
			   (format[index + 1] == '2'))
		    {
		      varsize = sizeof(trio_int32_t);
		      index += 2;
		    }
		  else if ((format[index] == '1') &&
			   (format[index + 1] == '6'))
		    {
		      varsize = sizeof(trio_int16_t);
		      index += 2;
		    }
		  else if (format[index] == '8')
		    {
		      varsize = sizeof(trio_int8_t);
		      index++;
		    }
		  else
		    return TRIO_ERROR_RETURN(TRIO_EINVAL, index);
		  
		  flags |= FLAGS_FIXED_SIZE;
		  break;
#endif

#if defined(QUALIFIER_WIDECHAR)
		case QUALIFIER_WIDECHAR:
		  flags |= FLAGS_WIDECHAR;
		  break;
#endif

#if defined(QUALIFIER_SIZE_T_UPPER)
		case QUALIFIER_SIZE_T_UPPER:
		  break;
#endif

#if defined(QUALIFIER_QUOTE)
		case QUALIFIER_QUOTE:
		  flags |= FLAGS_QUOTE;
		  break;
#endif

#if defined(QUALIFIER_STICKY)
		case QUALIFIER_STICKY:
		  flags |= FLAGS_STICKY;
		  gotSticky = TRUE;
		  break;
#endif
		  
#if defined(QUALIFIER_VARSIZE)
		case QUALIFIER_VARSIZE:
		  flags |= FLAGS_VARSIZE_PARAMETER;
		  parameterPosition++;
		  if (positional)
		    varsize = parameterPosition;
		  else
		    {
		      varsize = currentParam;
		      currentParam = varsize + 1;
		    }
		  if (currentParam > maxParam)
		    maxParam = currentParam;
		  break;
#endif

#if defined(QUALIFIER_ROUNDING_UPPER)
		case QUALIFIER_ROUNDING_UPPER:
		  flags |= FLAGS_ROUNDING;
		  break;
#endif

		default:
		  /* Bail out completely to make the error more obvious */
                  return TRIO_ERROR_RETURN(TRIO_EINVAL, index);
		}
	    } /* while qualifier */

	  /*
	   * Parameters only need the type and value. The value is
	   * read later.
	   */
	  if (flags & FLAGS_WIDTH_PARAMETER)
	    {
	      usedEntries[width] += 1;
	      parameters[pos].type = FORMAT_PARAMETER;
	      parameters[pos].flags = 0;
	      indices[width] = pos;
	      width = pos++;
	    }
	  if (flags & FLAGS_PRECISION_PARAMETER)
	    {
	      usedEntries[precision] += 1;
	      parameters[pos].type = FORMAT_PARAMETER;
	      parameters[pos].flags = 0;
	      indices[precision] = pos;
	      precision = pos++;
	    }
	  if (flags & FLAGS_BASE_PARAMETER)
	    {
	      usedEntries[base] += 1;
	      parameters[pos].type = FORMAT_PARAMETER;
	      parameters[pos].flags = 0;
	      indices[base] = pos;
	      base = pos++;
	    }
	  if (flags & FLAGS_VARSIZE_PARAMETER)
	    {
	      usedEntries[varsize] += 1;
	      parameters[pos].type = FORMAT_PARAMETER;
	      parameters[pos].flags = 0;
	      indices[varsize] = pos;
	      varsize = pos++;
	    }
	  
	  indices[currentParam] = pos;
	  
	  switch (format[index++])
	    {
#if defined(SPECIFIER_CHAR_UPPER)
	    case SPECIFIER_CHAR_UPPER:
	      flags |= FLAGS_WIDECHAR;
	      /* FALLTHROUGH */
#endif
	    case SPECIFIER_CHAR:
	      if (flags & FLAGS_LONG)
		flags |= FLAGS_WIDECHAR;
	      else if (flags & FLAGS_SHORT)
		flags &= ~FLAGS_WIDECHAR;
	      parameters[pos].type = FORMAT_CHAR;
	      break;

#if defined(SPECIFIER_STRING_UPPER)
	    case SPECIFIER_STRING_UPPER:
	      flags |= FLAGS_WIDECHAR;
	      /* FALLTHROUGH */
#endif
	    case SPECIFIER_STRING:
	      if (flags & FLAGS_LONG)
		flags |= FLAGS_WIDECHAR;
	      else if (flags & FLAGS_SHORT)
		flags &= ~FLAGS_WIDECHAR;
	      parameters[pos].type = FORMAT_STRING;
	      break;

	    case SPECIFIER_GROUP:
	      if (TYPE_SCAN == type)
		{
		  int depth = 1;
		  parameters[pos].type = FORMAT_GROUP;
		  if (format[index] == QUALIFIER_CIRCUMFLEX)
		    index++;
		  if (format[index] == SPECIFIER_UNGROUP)
		    index++;
		  if (format[index] == QUALIFIER_MINUS)
		    index++;
		  /* Skip nested brackets */
		  while (format[index] != NIL)
		    {
		      if (format[index] == SPECIFIER_GROUP)
			{
			  depth++;
			}
		      else if (format[index] == SPECIFIER_UNGROUP)
			{
			  if (--depth <= 0)
			    {
			      index++;
			      break;
			    }
			}
		      index++;
		    }
		}
	      break;
	      
	    case SPECIFIER_INTEGER:
	      parameters[pos].type = FORMAT_INT;
	      break;
	      
	    case SPECIFIER_UNSIGNED:
	      flags |= FLAGS_UNSIGNED;
	      parameters[pos].type = FORMAT_INT;
	      break;

	    case SPECIFIER_DECIMAL:
	      /* Disable base modifier */
	      flags &= ~FLAGS_BASE_PARAMETER;
	      base = BASE_DECIMAL;
	      parameters[pos].type = FORMAT_INT;
	      break;

	    case SPECIFIER_OCTAL:
	      flags |= FLAGS_UNSIGNED;
	      flags &= ~FLAGS_BASE_PARAMETER;
	      base = BASE_OCTAL;
	      parameters[pos].type = FORMAT_INT;
	      break;

#if defined(SPECIFIER_BINARY)
	    case SPECIFIER_BINARY_UPPER:
	      flags |= FLAGS_UPPER;
	      /* FALLTHROUGH */
	    case SPECIFIER_BINARY:
	      flags |= FLAGS_NILPADDING;
	      flags &= ~FLAGS_BASE_PARAMETER;
	      base = BASE_BINARY;
	      parameters[pos].type = FORMAT_INT;
	      break;
#endif

	    case SPECIFIER_HEX_UPPER:
	      flags |= FLAGS_UPPER;
	      /* FALLTHROUGH */
	    case SPECIFIER_HEX:
	      flags |= FLAGS_UNSIGNED;
	      flags &= ~FLAGS_BASE_PARAMETER;
	      base = BASE_HEX;
	      parameters[pos].type = FORMAT_INT;
	      break;

	    case SPECIFIER_FLOAT_E_UPPER:
	      flags |= FLAGS_UPPER;
	      /* FALLTHROUGH */
	    case SPECIFIER_FLOAT_E:
	      flags |= FLAGS_FLOAT_E;
	      parameters[pos].type = FORMAT_DOUBLE;
	      break;

	    case SPECIFIER_FLOAT_G_UPPER:
	      flags |= FLAGS_UPPER;
	      /* FALLTHROUGH */
	    case SPECIFIER_FLOAT_G:
	      flags |= FLAGS_FLOAT_G;
	      parameters[pos].type = FORMAT_DOUBLE;
	      break;

	    case SPECIFIER_FLOAT_F_UPPER:
	      flags |= FLAGS_UPPER;
	      /* FALLTHROUGH */
	    case SPECIFIER_FLOAT_F:
	      parameters[pos].type = FORMAT_DOUBLE;
	      break;

	    case SPECIFIER_POINTER:
	      if (sizeof(trio_pointer_t) == sizeof(trio_ulonglong_t))
		flags |= FLAGS_QUAD;
	      else if (sizeof(trio_pointer_t) == sizeof(long))
		flags |= FLAGS_LONG;
	      parameters[pos].type = FORMAT_POINTER;
	      break;

	    case SPECIFIER_COUNT:
	      parameters[pos].type = FORMAT_COUNT;
	      break;

#if defined(SPECIFIER_HEXFLOAT)
# if defined(SPECIFIER_HEXFLOAT_UPPER)
	    case SPECIFIER_HEXFLOAT_UPPER:
	      flags |= FLAGS_UPPER;
	      /* FALLTHROUGH */
# endif
	    case SPECIFIER_HEXFLOAT:
	      base = BASE_HEX;
	      parameters[pos].type = FORMAT_DOUBLE;
	      break;
#endif

#if defined(FORMAT_ERRNO)
	    case SPECIFIER_ERRNO:
	      parameters[pos].type = FORMAT_ERRNO;
	      break;
#endif

#if defined(SPECIFIER_USER_DEFINED_BEGIN)
	    case SPECIFIER_USER_DEFINED_BEGIN:
	      {
		unsigned int max;
		int without_namespace = TRUE;
		
		parameters[pos].type = FORMAT_USER_DEFINED;
		parameters[pos].user_name[0] = NIL;
		tmpformat = (char *)&format[index];
	      
		while ((ch = format[index]))
		  {
		    index++;
		    if (ch == SPECIFIER_USER_DEFINED_END)
		      {
			if (without_namespace)
			  {
			    /* We must get the handle first */
			    parameters[pos].type = FORMAT_PARAMETER;
			    parameters[pos].indexAfterSpecifier = index;
			    parameters[pos].flags = FLAGS_USER_DEFINED;
			    /* Adjust parameters for insertion of new one */
			    pos++;
			    usedEntries[currentParam] += 1;
			    parameters[pos].type = FORMAT_USER_DEFINED;
			    currentParam++;
			    indices[currentParam] = pos;
			    if (currentParam > maxParam)
			      maxParam = currentParam;
			  }
			/* Copy the user data */
			max = (unsigned int)(&format[index] - tmpformat);
			if (max > MAX_USER_DATA)
			  max = MAX_USER_DATA;
			trio_copy_max(parameters[pos].user_data,
				      max,
				      tmpformat);
			break; /* while */
		      }
		    if (ch == SPECIFIER_USER_DEFINED_SEPARATOR)
		      {
			without_namespace = FALSE;
			/* Copy the namespace for later looking-up */
			max = (int)(&format[index] - tmpformat);
			if (max > MAX_USER_NAME)
			  max = MAX_USER_NAME;
			trio_copy_max(parameters[pos].user_name,
				      max,
				      tmpformat);
			tmpformat = (char *)&format[index];
		      }
		  }
		if (ch != SPECIFIER_USER_DEFINED_END)
		  return TRIO_ERROR_RETURN(TRIO_EINVAL, index);
	      }
	      break;
#endif /* defined(SPECIFIER_USER_DEFINED_BEGIN) */
	      
	    default:
	      /* Bail out completely to make the error more obvious */
              return TRIO_ERROR_RETURN(TRIO_EINVAL, index);
	    }

	  /*  Count the number of times this entry has been used */
	  usedEntries[currentParam] += 1;
	  
	  /* Find last sticky parameters */
	  if (gotSticky && !(flags & FLAGS_STICKY))
	    {
	      for (i = pos - 1; i >= 0; i--)
		{
		  if (parameters[i].type == FORMAT_PARAMETER)
		    continue;
		  if ((parameters[i].flags & FLAGS_STICKY) &&
		      (parameters[i].type == parameters[pos].type))
		    {
		      /* Do not overwrite current qualifiers */
		      flags |= (parameters[i].flags & (unsigned long)~FLAGS_STICKY);
		      if (width == NO_WIDTH)
			width = parameters[i].width;
		      if (precision == NO_PRECISION)
			precision = parameters[i].precision;
		      if (base == NO_BASE)
			base = parameters[i].base;
		      break;
		    }
		}
	    }
	  
	  parameters[pos].indexAfterSpecifier = index;
	  parameters[pos].flags = flags;
	  parameters[pos].width = width;
	  parameters[pos].precision = precision;
	  parameters[pos].base = (base == NO_BASE) ? BASE_DECIMAL : base;
	  parameters[pos].varsize = varsize;
	  pos++;
	  
	  if (! positional)
	    parameterPosition++;
	  
	} /* if identifier */
      
    } /* while format characters left */

  for (num = 0; num <= maxParam; num++)
    {
      if (usedEntries[num] != 1)
	{
	  if (usedEntries[num] == 0) /* gap detected */
	    return TRIO_ERROR_RETURN(TRIO_EGAP, num);
	  else /* double references detected */
	    return TRIO_ERROR_RETURN(TRIO_EDBLREF, num);
	}
      
      i = indices[num];

      /*
       * FORMAT_PARAMETERS are only present if they must be read,
       * so it makes no sense to check the ignore flag (besides,
       * the flags variable is not set for that particular type)
       */
      if ((parameters[i].type != FORMAT_PARAMETER) &&
	  (parameters[i].flags & FLAGS_IGNORE))
	continue; /* for all arguments */

      /*
       * The stack arguments are read according to ANSI C89
       * default argument promotions:
       *
       *  char           = int
       *  short          = int
       *  unsigned char  = unsigned int
       *  unsigned short = unsigned int
       *  float          = double
       *
       * In addition to the ANSI C89 these types are read (the
       * default argument promotions of C99 has not been
       * considered yet)
       *
       *  long long
       *  long double
       *  size_t
       *  ptrdiff_t
       *  intmax_t
       */
      switch (parameters[i].type)
	{
	case FORMAT_GROUP:
	case FORMAT_STRING:
#if TRIO_WIDECHAR
	  if (flags & FLAGS_WIDECHAR)
	    {
	      parameters[i].data.wstring = (argarray == NULL)
		? va_arg(*arglist, trio_wchar_t *)
		: (trio_wchar_t *)(argarray[num]);
	    }
	  else
#endif
	    {
	      parameters[i].data.string = (argarray == NULL)
		? va_arg(*arglist, char *)
		: (char *)(argarray[num]);
	    }
	  break;

#if defined(FORMAT_USER_DEFINED)
	case FORMAT_USER_DEFINED:
#endif
	case FORMAT_POINTER:
	case FORMAT_COUNT:
	case FORMAT_UNKNOWN:
	  parameters[i].data.pointer = (argarray == NULL)
	    ? va_arg(*arglist, trio_pointer_t )
	    : argarray[num];
	  break;

	case FORMAT_CHAR:
	case FORMAT_INT:
	  if (TYPE_SCAN == type)
	    {
              if (argarray == NULL)
                parameters[i].data.pointer = 
                  (trio_pointer_t)va_arg(*arglist, trio_pointer_t);
              else
                {
                  if (parameters[i].type == FORMAT_CHAR)
                    parameters[i].data.pointer =
                      (trio_pointer_t)((char *)argarray[num]);
                  else if (parameters[i].flags & FLAGS_SHORT)
                    parameters[i].data.pointer =
                      (trio_pointer_t)((short *)argarray[num]);
                  else
                    parameters[i].data.pointer =
                      (trio_pointer_t)((int *)argarray[num]);
                }
	    }
	  else
	    {
#if defined(QUALIFIER_VARSIZE) || defined(QUALIFIER_FIXED_SIZE)
	      if (parameters[i].flags
		  & (FLAGS_VARSIZE_PARAMETER | FLAGS_FIXED_SIZE))
		{
		  if (parameters[i].flags & FLAGS_VARSIZE_PARAMETER)
		    {
		      /*
		       * Variable sizes are mapped onto the fixed sizes, in
		       * accordance with integer promotion.
		       *
		       * Please note that this may not be portable, as we
		       * only guess the size, not the layout of the numbers.
		       * For example, if int is little-endian, and long is
		       * big-endian, then this will fail.