gdbtypes.h

早期freebsd实现

/* Internal type definitions for GDB.
   Copyright (C) 1992 Free Software Foundation, Inc.
   Contributed by Cygnus Support, using pieces from other GDB modules.

This file is part of GDB.

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.

This program 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 General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */

#if !defined (GDBTYPES_H)
#define GDBTYPES_H 1

/* When gdb creates fundamental types, it uses one of the following
   type identifiers.  The identifiers are used to index a vector of
   pointers to any types that are created. */

#define FT_VOID			0
#define FT_BOOLEAN		1
#define FT_CHAR			2
#define FT_SIGNED_CHAR		3
#define FT_UNSIGNED_CHAR	4
#define FT_SHORT		5
#define FT_SIGNED_SHORT		6
#define FT_UNSIGNED_SHORT	7
#define FT_INTEGER		8
#define FT_SIGNED_INTEGER	9
#define FT_UNSIGNED_INTEGER	10
#define FT_LONG			11
#define FT_SIGNED_LONG		12
#define FT_UNSIGNED_LONG	13
#define FT_LONG_LONG		14
#define FT_SIGNED_LONG_LONG	15
#define FT_UNSIGNED_LONG_LONG	16
#define FT_FLOAT		17
#define FT_DBL_PREC_FLOAT	18
#define FT_EXT_PREC_FLOAT	19
#define FT_COMPLEX		20
#define FT_DBL_PREC_COMPLEX	21
#define FT_EXT_PREC_COMPLEX	22
#define FT_STRING		23
#define FT_FIXED_DECIMAL	24
#define FT_FLOAT_DECIMAL	25

#define FT_NUM_MEMBERS		26

/* Different kinds of data types are distinguished by the `code' field.  */

enum type_code
{
  TYPE_CODE_UNDEF,		/* Not used; catches errors */
  TYPE_CODE_PTR,		/* Pointer type */
  TYPE_CODE_ARRAY,		/* Array type, lower bound zero */
  TYPE_CODE_STRUCT,		/* C struct or Pascal record */
  TYPE_CODE_UNION,		/* C union or Pascal variant part */
  TYPE_CODE_ENUM,		/* Enumeration type */
  TYPE_CODE_FUNC,		/* Function type */
  TYPE_CODE_INT,		/* Integer type */
  TYPE_CODE_FLT,		/* Floating type */
  TYPE_CODE_VOID,		/* Void type (values zero length) */
  TYPE_CODE_SET,		/* Pascal sets */
  TYPE_CODE_RANGE,		/* Range (integers within spec'd bounds) */
  TYPE_CODE_PASCAL_ARRAY,	/* Array with explicit type of index */
  TYPE_CODE_ERROR,              /* Unknown type */

  /* C++ */
  TYPE_CODE_MEMBER,		/* Member type */
  TYPE_CODE_METHOD,		/* Method type */
  TYPE_CODE_REF,		/* C++ Reference types */

  /* Modula-2 */
  TYPE_CODE_CHAR,		/* *real* character type */
  TYPE_CODE_BOOL		/* Builtin Modula-2 BOOLEAN */
};

/* For now allow source to use TYPE_CODE_CLASS for C++ classes, as an
   alias for TYPE_CODE_STRUCT.  Eventually these should probably be
   officially distinct types within gdb. */

#define TYPE_CODE_CLASS TYPE_CODE_STRUCT

/* Some bits for the type's flags word. */

/* Explicitly unsigned integer type */

#define TYPE_FLAG_UNSIGNED	(1 << 0)

/* Explicitly signed integer type */

#define TYPE_FLAG_SIGNED	(1 << 1)

/* This appears in a type's flags word if it is a stub type (eg. if
   someone referenced a type that wasn't defined in a source file
   via (struct sir_not_appearing_in_this_film *)).  */

#define TYPE_FLAG_STUB		(1 << 2)


struct type
{

  /* Code for kind of type */

  enum type_code code;

  /* Name of this type, or NULL if none.
     This is used for printing only, except by poorly designed C++ code.
     Type names specified as input are defined by symbols.  */

  char *name;

  /* Length in bytes of storage for a value of this type */

  unsigned length;

  /* Every type is now associated with a particular objfile, and the
     type is allocated on the type_obstack for that objfile.  One problem
     however, is that there are times when gdb allocates new types while
     it is not in the process of reading symbols from a particular objfile.
     Fortunately, these happen when the type being created is a derived
     type of an existing type, such as in lookup_pointer_type().  So
     we can just allocate the new type using the same objfile as the
     existing type, but to do this we need a backpointer to the objfile
     from the existing type.  Yes this is somewhat ugly, but without
     major overhaul of the internal type system, it can't be avoided
     for now. */

  struct objfile *objfile;

  /* For a pointer type, describes the type of object pointed to.
     For an array type, describes the type of the elements.
     For a function or method type, describes the type of the return value.
     For a range type, describes the type of the full range.
     Unused otherwise.  */

  struct type *target_type;

  /* Type that is a pointer to this type.
     NULL if no such pointer-to type is known yet.
     The debugger may add the address of such a type
     if it has to construct one later.  */ 

  struct type *pointer_type;

  /* C++: also need a reference type.  */

  struct type *reference_type;

  /* Type that is a function returning this type.
     NULL if no such function type is known here.
     The debugger may add the address of such a type
     if it has to construct one later.  */

  struct type *function_type;

  /* Flags about this type.  */

  short flags;

  /* Number of fields described for this type */

  short nfields;

  /* For structure and union types, a description of each field.
     For set and pascal array types, there is one "field",
     whose type is the domain type of the set or array.
     For range types, there are two "fields",
     the minimum and maximum values (both inclusive).
     For enum types, each possible value is described by one "field".
     For C++ classes, there is one field for each base class (if it is
     a derived class) plus one field for each class data member.  Member
     functions are recorded elsewhere.

     Using a pointer to a separate array of fields
     allows all types to have the same size, which is useful
     because we can allocate the space for a type before
     we know what to put in it.  */

  struct field
    {

      /* Position of this field, counting in bits from start of
	 containing structure.  For a function type, this is the
	 position in the argument list of this argument.
	 For a range bound or enum value, this is the value itself.
	 For BITS_BIG_ENDIAN=1 targets, it is the bit offset to the MSB.
	 For BITS_BIG_ENDIAN=0 targets, it is the bit offset to the LSB. */

      int bitpos;

      /* Size of this field, in bits, or zero if not packed.
	 For an unpacked field, the field's type's length
	 says how many bytes the field occupies.  */

      int bitsize;

      /* In a struct or enum type, type of this field.
	 In a function type, type of this argument.
	 In an array type, the domain-type of the array.  */

      struct type *type;

      /* Name of field, value or argument.
	 NULL for range bounds and array domains.  */

      char *name;

    } *fields;

  /* For types with virtual functions, VPTR_BASETYPE is the base class which
     defined the virtual function table pointer.  VPTR_FIELDNO is
     the field number of that pointer in the structure.

     For types that are pointer to member types, VPTR_BASETYPE
     is the type that this pointer is a member of.

     Unused otherwise.  */

  struct type *vptr_basetype;

  int vptr_fieldno;

  /* Slot to point to additional language-specific fields of this type.  */

  union type_specific
    {

      /* ARG_TYPES is for TYPE_CODE_METHOD and TYPE_CODE_FUNC.  */

      struct type **arg_types;

      /* CPLUS_STUFF is for TYPE_CODE_STRUCT.  It is initialized to point to
	 cplus_struct_default, a default static instance of a struct
	 cplus_struct_type. */

      struct cplus_struct_type *cplus_stuff;

    } type_specific;
};

#define	NULL_TYPE ((struct type *) 0)

/* C++ language-specific information for TYPE_CODE_STRUCT and TYPE_CODE_UNION
   nodes.  */

struct cplus_struct_type
{
  /* Number of base classes this type derives from. */

  short n_baseclasses;

  /* Number of methods with unique names.  All overloaded methods with
     the same name count only once. */

  short nfn_fields;

  /* Number of methods described for this type plus all the
     methods that it derives from.  */

  int nfn_fields_total;

  /* For derived classes, the number of base classes is given by n_baseclasses
     and virtual_field_bits is a bit vector containing one bit per base class.
     If the base class is virtual, the corresponding bit will be set.
     I.E, given:

	class A{};
	class B{};
	class C : public B, public virtual A {};

     B is a baseclass of C; A is a virtual baseclass for C.
     This is a C++ 2.0 language feature. */

  B_TYPE *virtual_field_bits;

  /* For classes with private fields, the number of fields is given by
     nfields and private_field_bits is a bit vector containing one bit
     per field.
     If the field is private, the corresponding bit will be set. */

  B_TYPE *private_field_bits;

  /* For classes with protected fields, the number of fields is given by
     nfields and protected_field_bits is a bit vector containing one bit
     per field.
     If the field is private, the corresponding bit will be set. */

  B_TYPE *protected_field_bits;

  /* For classes, structures, and unions, a description of each field,
     which consists of an overloaded name, followed by the types of
     arguments that the method expects, and then the name after it
     has been renamed to make it distinct.

     fn_fieldlists points to an array of nfn_fields of these. */

  struct fn_fieldlist
    {

      /* The overloaded name.  */

      char *name;