cplus-dem.c

gcc库的原代码,对编程有很大帮助.

	Numeric conversion is ASCII dependent (FIXME).

 */

static int
demangle_qualified (work, mangled, result, isfuncname, append)
     struct work_stuff *work;
     const char **mangled;
     string *result;
     int isfuncname;
     int append;
{
  int qualifiers;
  int namelength;
  int success = 1;
  const char *p;
  char num[2];
  string temp;

  string_init (&temp);
  switch ((*mangled)[1])
    {
    case '_':
      /* GNU mangled name with more than 9 classes.  The count is preceded
	 by an underscore (to distinguish it from the <= 9 case) and followed
	 by an underscore.  */
      p = *mangled + 2;
      qualifiers = atoi (p);
      if (!isdigit (*p) || *p == '0')
	success = 0;

      /* Skip the digits.  */
      while (isdigit (*p))
	++p;

      if (*p != '_')
	success = 0;

      *mangled = p + 1;
      break;

    case '1':
    case '2':
    case '3':
    case '4':
    case '5':
    case '6':
    case '7':
    case '8':
    case '9':
      /* The count is in a single digit.  */
      num[0] = (*mangled)[1];
      num[1] = '\0';
      qualifiers = atoi (num);

      /* If there is an underscore after the digit, skip it.  This is
	 said to be for ARM-qualified names, but the ARM makes no
	 mention of such an underscore.  Perhaps cfront uses one.  */
      if ((*mangled)[2] == '_')
	{
	  (*mangled)++;
	}
      (*mangled) += 2;
      break;

    case '0':
    default:
      success = 0;
    }

  if (!success)
    return success;

  /* Pick off the names and collect them in the temp buffer in the order
     in which they are found, separated by '::'. */

  while (qualifiers-- > 0)
    {
      if (*mangled[0] == '_') 
	*mangled = *mangled + 1;
      if (*mangled[0] == 't')
	{
	  success = demangle_template(work, mangled, &temp, 0);
	  if (!success) break;
	}
      else
        {	
	  namelength = consume_count (mangled);
      	  if (strlen (*mangled) < namelength)
	    {
	    /* Simple sanity check failed */
	       success = 0;
	       break;
	    }
      	  string_appendn (&temp, *mangled, namelength);
      	  *mangled += namelength;
	}
      if (qualifiers > 0)
        {
          string_appendn (&temp, "::", 2);
        }
    }

  /* If we are using the result as a function name, we need to append
     the appropriate '::' separated constructor or destructor name.
     We do this here because this is the most convenient place, where
     we already have a pointer to the name and the length of the name. */

  if (isfuncname && (work->constructor & 1 || work->destructor & 1))
    {
      string_appendn (&temp, "::", 2);
      if (work -> destructor & 1)
	{
	  string_append (&temp, "~");
	}
      string_appendn (&temp, (*mangled) - namelength, namelength);
    }

  /* Now either prepend the temp buffer to the result, or append it, 
     depending upon the state of the append flag. */

  if (append)
    {
      string_appends (result, &temp);
    }
  else
    {
      if (!STRING_EMPTY (result))
	{
	  string_appendn (&temp, "::", 2);
	}
      string_prepends (result, &temp);
    }

  string_delete (&temp);
  return (success);
}

/*

LOCAL FUNCTION

	get_count -- convert an ascii count to integer, consuming tokens

SYNOPSIS

	static int
	get_count (const char **type, int *count)

DESCRIPTION

	Return 0 if no conversion is performed, 1 if a string is converted.
*/

static int
get_count (type, count)
     const char **type;
     int *count;
{
  const char *p;
  int n;

  if (!isdigit (**type))
    {
      return (0);
    }
  else
    {
      *count = **type - '0';
      (*type)++;
      if (isdigit (**type))
	{
	  p = *type;
	  n = *count;
	  do 
	    {
	      n *= 10;
	      n += *p - '0';
	      p++;
	    } 
	  while (isdigit (*p));
	  if (*p == '_')
	    {
	      *type = p + 1;
	      *count = n;
	    }
	}
    }
  return (1);
}

/* result will be initialised here; it will be freed on failure */

static int
do_type (work, mangled, result)
     struct work_stuff *work;
     const char **mangled;
     string *result;
{
  int n;
  int done;
  int success;
  string decl;
  const char *remembered_type;
  int constp;
  int volatilep;

  string_init (&decl);
  string_init (result);

  done = 0;
  success = 1;
  while (success && !done)
    {
      int member;
      switch (**mangled)
	{

	/* A pointer type */
	case 'P':
	case 'p':
	  (*mangled)++;
	  string_prepend (&decl, "*");
	  break;

	/* A reference type */
	case 'R':
	  (*mangled)++;
	  string_prepend (&decl, "&");
	  break;

	/* An array */
	case 'A':
	  {
	    const char *p = ++(*mangled);

	    string_prepend (&decl, "(");
	    string_append (&decl, ")[");
	    /* Copy anything up until the next underscore (the size of the
	       array).  */
	    while (**mangled && **mangled != '_')
	      ++(*mangled);
	    if (**mangled == '_')
	      {
		string_appendn (&decl, p, *mangled - p);
		string_append (&decl, "]");             
		*mangled += 1;
	      }
	    else
	      success = 0;
	    break;
	  }

	/* A back reference to a previously seen type */
	case 'T':
	  (*mangled)++;
	  if (!get_count (mangled, &n) || n >= work -> ntypes)
	    {
	      success = 0;
	    }
	  else
	    {
	      remembered_type = work -> typevec[n];
	      mangled = &remembered_type;
	    }
	  break;

	/* A function */
	case 'F':
	  (*mangled)++;
	  if (!STRING_EMPTY (&decl) && decl.b[0] == '*')
	    {
	      string_prepend (&decl, "(");
	      string_append (&decl, ")");
	    }
	  /* After picking off the function args, we expect to either find the
	     function return type (preceded by an '_') or the end of the
	     string. */
	  if (!demangle_args (work, mangled, &decl)
	      || (**mangled != '_' && **mangled != '\0'))
	    {
	      success = 0;
	    }
	  if (success && (**mangled == '_'))
	    {
	      (*mangled)++;
	    }
	  break;

	case 'M':
	case 'O':
	  {
	    constp = 0;
	    volatilep = 0;

	    member = **mangled == 'M';
	    (*mangled)++;
	    if (!isdigit (**mangled))
	      {
		success = 0;
		break;
	      }
	    n = consume_count (mangled);
	    if (strlen (*mangled) < n)
	      {
		success = 0;
		break;
	      }
	    string_append (&decl, ")");
	    string_prepend (&decl, "::");
	    string_prependn (&decl, *mangled, n);
	    string_prepend (&decl, "(");
	    *mangled += n;
	    if (member)
	      {
		if (**mangled == 'C')
		  {
		    (*mangled)++;
		    constp = 1;
		  }
		if (**mangled == 'V')
		  {
		    (*mangled)++;
		    volatilep = 1;
		  }
		if (*(*mangled)++ != 'F')
		  {
		    success = 0;
		    break;
		  }
	      }
	    if ((member && !demangle_args (work, mangled, &decl))
		|| **mangled != '_')
	      {
		success = 0;
		break;
	      }
	    (*mangled)++;
	    if (! PRINT_ANSI_QUALIFIERS)
	      {
		break;
	      }
	    if (constp)
	      {
		APPEND_BLANK (&decl);
		string_append (&decl, "const");
	      }
	    if (volatilep)
	      {
		APPEND_BLANK (&decl);
		string_append (&decl, "volatile");
	      }
	    break;
	  }
        case 'G':
	    (*mangled)++;
	    break;

	case 'C':
	  (*mangled)++;
/*
	  if ((*mangled)[1] == 'P')
	    {
*/
	      if (PRINT_ANSI_QUALIFIERS)
		{
		  if (!STRING_EMPTY (&decl))
		    {
		      string_prepend (&decl, " ");
		    }
		  string_prepend (&decl, "const");
		}
	      break;
/*
	    }
*/

	  /* fall through */
	default:
	  done = 1;
	  break;
	}
    }

  switch (**mangled)
    {
      /* A qualified name, such as "Outer::Inner". */
      case 'Q':
        success = demangle_qualified (work, mangled, result, 0, 1);
	break;

      default:
	success = demangle_fund_type (work, mangled, result);
	break;
    }

  if (success)
    {
      if (!STRING_EMPTY (&decl))
	{
	  string_append (result, " ");
	  string_appends (result, &decl);
	}
    }
  else
    {
      string_delete (result);
    }
  string_delete (&decl);
  return (success);
}

/* Given a pointer to a type string that represents a fundamental type
   argument (int, long, unsigned int, etc) in TYPE, a pointer to the
   string in which the demangled output is being built in RESULT, and
   the WORK structure, decode the types and add them to the result.

   For example:

   	"Ci"	=>	"const int"
	"Sl"	=>	"signed long"
	"CUs"	=>	"const unsigned short"

   */

static int
demangle_fund_type (work, mangled, result)
     struct work_stuff *work;
     const char **mangled;
     string *result;
{
  int done = 0;
  int success = 1;

  /* First pick off any type qualifiers.  There can be more than one. */

  while (!done)
    {
      switch (**mangled)
	{
	  case 'C':
	    (*mangled)++;
	    if (PRINT_ANSI_QUALIFIERS)
	      {
		APPEND_BLANK (result);
		string_append (result, "const");
	      }
	    break;
	  case 'U':
	    (*mangled)++;
	    APPEND_BLANK (result);
	    string_append (result, "unsigned");
	    break;
	  case 'S': /* signed char only */
	    (*mangled)++;
	    APPEND_BLANK (result);
	    string_append (result, "signed");
	    break;
	  case 'V':
	    (*mangled)++;
	    if (PRINT_ANSI_QUALIFIERS)
	      {
		APPEND_BLANK (result);
		string_append (result, "volatile");
	      }
	    break;
	  default:
	    done = 1;
	    break;
	}
    }

  /* Now pick off the fundamental type.  There can be only one. */

  switch (**mangled)
    {
      case '\0':
      case '_':
	break;
      case 'v':
	(*mangled)++;
	APPEND_BLANK (result);
	string_append (result, "void");
	break;
      case 'x':
	(*mangled)++;
	APPEND_BLANK (result);
	string_append (result, "long long");
	break;
      case 'l':
	(*mangled)++;
	APPEND_BLANK (result);
	string_append (result, "long");
	break;
      case 'i':
	(*mangled)++;
	APPEND_BLANK (result);
	string_append (result, "int");
	break;
      case 's':
	(*mangled)++;
	APPEND_BLANK (result);
	string_append (result, "short");
	break;
      case 'b':
	(*mangled)++;
	APPEND_BLANK (result);
	string_append (result, "bool");
	break;
      case 'c':
	(*mangled)++;
	APPEND_BLANK (result);
	string_append (result, "char");
	break;
      case 'w':
	(*mangled)++;
	APPEND_BLANK (result);
	string_append (result, "wchar_t");
	break;
      case 'r':
	(*mangled)++;
	APPEND_BLANK (result);
	string_append (result, "long double");
	break;
      case 'd':
	(*mangled)++;
	APPEND_BLANK (result);
	string_append (result, "double");
	break;
      case 'f':
	(*mangled)++;
	APPEND_BLANK (result);
	string_append (result, "float");
	break;
      case 'G':
	(*mangled)++;
	if (!isdigit (**mangled))
	  {
	    success = 0;
	    break;
	  }
	/* fall through */
      /* An explicit type, such as "6mytype" or "7integer" */
      case '0':
      case '1':
      case '2':
      case '3':
      case '4':
      case '5':
      case '6':
      case '7':
      case '8':
      case '9':
	APPEND_BLANK (result);
	if (!demangle_class_name (work, mangled, result)) {
	  --result->p;
	  success = 0;
	}
	break;
      case 't':
        success = demangle_template(work,mangled, result, 0);
        break;