cplus-dem.c

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  if (strncmp (*mangled, ARM_VTABLE_STRING, ARM_VTABLE_STRLEN) == 0)
    {
      /* Found a ARM style virtual table, get past ARM_VTABLE_STRING
         and create the decl.  Note that we consume the entire mangled
	 input string, which means that demangle_signature has no work
	 to do.  */
      scan = *mangled + ARM_VTABLE_STRLEN;
      while (*scan != '\0')        /* first check it can be demangled */
        {
          n = consume_count (&scan);
          if (n==0)
	    {
	      return (0);           /* no good */
	    }
          scan += n;
          if (scan[0] == '_' && scan[1] == '_')
	    {
	      scan += 2;
	    }
        }
      (*mangled) += ARM_VTABLE_STRLEN;
      while (**mangled != '\0')
	{
	  n = consume_count (mangled);
	  string_prependn (declp, *mangled, n);
	  (*mangled) += n;
	  if ((*mangled)[0] == '_' && (*mangled)[1] == '_')
	    {
	      string_prepend (declp, "::");
	      (*mangled) += 2;
	    }
	}
      string_append (declp, " virtual table");
    }
  else
    {
      success = 0;
    }
  return (success);
}

/*

LOCAL FUNCTION

	demangle_qualified -- demangle 'Q' qualified name strings

SYNOPSIS

	static int
	demangle_qualified (struct work_stuff *, const char *mangled,
			    string *result, int isfuncname, int append);

DESCRIPTION

	Demangle a qualified name, such as "Q25Outer5Inner" which is
	the mangled form of "Outer::Inner".  The demangled output is
	prepended or appended to the result string according to the
	state of the append flag.

	If isfuncname is nonzero, then the qualified name we are building
	is going to be used as a member function name, so if it is a
	constructor or destructor function, append an appropriate
	constructor or destructor name.  I.E. for the above example,
	the result for use as a constructor is "Outer::Inner::Inner"
	and the result for use as a destructor is "Outer::Inner::~Inner".

BUGS

	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) && **mangled != 't')
	      {
		success = 0;
		break;
	      }

	    string_append (&decl, ")");
	    string_prepend (&decl, "::");
	    if (isdigit (**mangled)) 
	      {
		n = consume_count (mangled);
		if (strlen (*mangled) < n)
		  {
		    success = 0;
		    break;
		  }
		string_prependn (&decl, *mangled, n);
		*mangled += n;
	      }
	    else
	      {
		string temp;
		string_init (&temp);
		success = demangle_template (work, mangled, &temp, NULL);
		if (success)
		  {
		    string_prependn (&decl, temp.b, temp.p - temp.b);
		    string_clear (&temp);
		  }
		else
		  break;
	      }
	    string_prepend (&decl, "(");
	    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.  */